Biology, distribution and management of the globally invasive weed Solanum elaeagnifolium Cav (silverleaf nightshade): A global review of current and future management challenges
- Roberts, Jason, Florentine, Singarayer
- Authors: Roberts, Jason , Florentine, Singarayer
- Date: 2022
- Type: Text , Journal article , Review
- Relation: Weed Research Vol. 62, no. 6 (2022), p. 393-403
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- Description: Solanum elaeagnifolium Cav (silverleaf nightshade) is a deep-rooted, multi-stemmed, perennial, herbaceous woody plant that has been observed to threaten agricultural and native biodiversity worldwide. It is widely agreed that without efficient integrated management, S. elaeagnifolium will continue to cause significant economic and environmental damage across multiple scales. It is estimated that the annual economic impact of S. elaeagnifolium in Australia exceeds AUD $62 million, with this figure likely to be much higher in other countries invaded by this plant. It can also tolerate a high level of abiotic stress and survive in a range of temperatures (below freezing point to 34°C) and areas with an average yearly rainfall between 250 and 600 mm. Its extensive deep taproot system is capable of regenerating asexually and with its many seed dispersal mechanisms; it can quickly spread and establish itself within a region. This makes containment and management of the species especially challenging. Previous management has largely been focused on biological control, competition, essential oils, grazing pressure, herbicide application and manual removal. Despite the large range of available management techniques, there has been little success in the long-term control of S. elaeagnifolium, and only a handful of methods such as essential oils and herbicide application have shown reasonable success for controlling this weed. Therefore, this review aims to synthesise the identified and potentially useful approaches to control S. elaeagnifolium that have been recorded in the literature which deal with its biology, distribution and management. It also explores previous and current management techniques to ascertain the research gaps and knowledge required to assist in the effective and economically sustainable management of this invasive weed. © 2022 The Authors. Weed Research published by John Wiley & Sons Ltd on behalf of European Weed Research Society.
- Authors: Roberts, Jason , Florentine, Singarayer
- Date: 2022
- Type: Text , Journal article , Review
- Relation: Weed Research Vol. 62, no. 6 (2022), p. 393-403
- Full Text:
- Reviewed:
- Description: Solanum elaeagnifolium Cav (silverleaf nightshade) is a deep-rooted, multi-stemmed, perennial, herbaceous woody plant that has been observed to threaten agricultural and native biodiversity worldwide. It is widely agreed that without efficient integrated management, S. elaeagnifolium will continue to cause significant economic and environmental damage across multiple scales. It is estimated that the annual economic impact of S. elaeagnifolium in Australia exceeds AUD $62 million, with this figure likely to be much higher in other countries invaded by this plant. It can also tolerate a high level of abiotic stress and survive in a range of temperatures (below freezing point to 34°C) and areas with an average yearly rainfall between 250 and 600 mm. Its extensive deep taproot system is capable of regenerating asexually and with its many seed dispersal mechanisms; it can quickly spread and establish itself within a region. This makes containment and management of the species especially challenging. Previous management has largely been focused on biological control, competition, essential oils, grazing pressure, herbicide application and manual removal. Despite the large range of available management techniques, there has been little success in the long-term control of S. elaeagnifolium, and only a handful of methods such as essential oils and herbicide application have shown reasonable success for controlling this weed. Therefore, this review aims to synthesise the identified and potentially useful approaches to control S. elaeagnifolium that have been recorded in the literature which deal with its biology, distribution and management. It also explores previous and current management techniques to ascertain the research gaps and knowledge required to assist in the effective and economically sustainable management of this invasive weed. © 2022 The Authors. Weed Research published by John Wiley & Sons Ltd on behalf of European Weed Research Society.
Challenges inherent in controlling prickly pear species; a global review of the properties of Opuntia stricta, Opuntia ficus-indica and Opuntia monacantha
- Humphries, Talia, Campbell, Shane, Florentine, Singarayer
- Authors: Humphries, Talia , Campbell, Shane , Florentine, Singarayer
- Date: 2022
- Type: Text , Journal article , Review
- Relation: Plants Vol. 11, no. 23 (2022), p.
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- Description: Opuntia species (prickly pear) were deliberately introduced to many countries around the world for fruit, cochineal dye production, living fencing or as ornamentals. They are now some of the world’s most significant weeds, particularly in regions with warm and or dry climates, as they pose threats to economic and environmental assets. In addition, they can cause considerable health issues for humans and animals. Opuntia spp. have prolific reproduction abilities, being able to reproduce both vegetatively and by seed. They have generalist pollination and dispersal requirements, which promotes their establishment and spread. Opuntia stricta, O. monacantha and O. ficus-indica are the most globally widespread of the Opuntia spp. In many countries, biological control agents, particularly the cactus moth (Cactoblastis cactorum) and various cochineal insects from the Dactylopius genus, have successfully reduced land-scape scale populations. On a smaller scale, controlling these weeds by either injecting or spraying the cladodes with herbicides can provide effective control. Care must be taken during herbicide treatments as any untreated areas will regenerate. While biological control is the most cost and time effective control method for landscape-scale infestations, further research into the combined efficacy of herbicides, fire, grubbing and pre-burial techniques would be beneficial for land managers to control small-scale and establishing populations. It would also be useful to have greater knowledge of the potential seedbank longevity and seed ecology of these species so that integrated management strategies can be developed to not only deal with initial populations but also the subsequent seedling regrowth. © 2022 by the authors.
- Authors: Humphries, Talia , Campbell, Shane , Florentine, Singarayer
- Date: 2022
- Type: Text , Journal article , Review
- Relation: Plants Vol. 11, no. 23 (2022), p.
- Full Text:
- Reviewed:
- Description: Opuntia species (prickly pear) were deliberately introduced to many countries around the world for fruit, cochineal dye production, living fencing or as ornamentals. They are now some of the world’s most significant weeds, particularly in regions with warm and or dry climates, as they pose threats to economic and environmental assets. In addition, they can cause considerable health issues for humans and animals. Opuntia spp. have prolific reproduction abilities, being able to reproduce both vegetatively and by seed. They have generalist pollination and dispersal requirements, which promotes their establishment and spread. Opuntia stricta, O. monacantha and O. ficus-indica are the most globally widespread of the Opuntia spp. In many countries, biological control agents, particularly the cactus moth (Cactoblastis cactorum) and various cochineal insects from the Dactylopius genus, have successfully reduced land-scape scale populations. On a smaller scale, controlling these weeds by either injecting or spraying the cladodes with herbicides can provide effective control. Care must be taken during herbicide treatments as any untreated areas will regenerate. While biological control is the most cost and time effective control method for landscape-scale infestations, further research into the combined efficacy of herbicides, fire, grubbing and pre-burial techniques would be beneficial for land managers to control small-scale and establishing populations. It would also be useful to have greater knowledge of the potential seedbank longevity and seed ecology of these species so that integrated management strategies can be developed to not only deal with initial populations but also the subsequent seedling regrowth. © 2022 by the authors.
Effect of Rhizome Fragment Length and Burial Depth on the emergence of a tropical invasive Weed Cyperus aromaticus (Navua Sedge)
- Chadha, Aakansha, Florentine, Singarayer, Dhileepan, Kunjithapatham, Turville, Christopher
- Authors: Chadha, Aakansha , Florentine, Singarayer , Dhileepan, Kunjithapatham , Turville, Christopher
- Date: 2022
- Type: Text , Journal article
- Relation: Plants Vol. 11, no. 23 (2022), p.
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- Description: Cyperus aromaticus (Navua sedge) is a problematic perennial weed in pastures and crops including sugarcane, banana, rice, and fruits and vegetables in tropical climates. It reproduces both via rhizomes and seeds. As a regenerative and storage organ, these rhizomes play an important part in the invasion, establishment, and persistence of this weed. To eliminate their regenerative ability, it is important to understand the regrowth potential with respect to rhizome fragment size and burial depth. This study evaluated the emergence of C. aromaticus from rhizomes in a controlled condition. Three different sizes of rhizome fragments were buried at seven depths of up to 20 cm in two soil types. The experimental measurements included (i) the time for tillers to emerge, (ii) the cumulative emergence of tillers, recorded weekly, and (iii) the number of underground emerging tillers. The cumulative shoot emergence and the number of underground tillers produced were found to be positively correlated with the initial length of the rhizome fragments and negatively correlated with the burial depth. The time for the emergence of the tillers was negatively correlated with the burial depth, and soil type had no significant effect on any of the parameters recorded. There was no emergence recorded from rhizomes buried at 15 cm depth and deeper, irrespective of their size. Our results indicate that the combination of the fragmentation of rhizomes into small pieces and a deep burial, below 15 cm, is an important aspect to control the regeneration of C. aromaticus from rhizomes, if tillage is carried out, and can therefore form a part of an integrated weed management strategy for this troublesome weed. © 2022 by the authors.
- Authors: Chadha, Aakansha , Florentine, Singarayer , Dhileepan, Kunjithapatham , Turville, Christopher
- Date: 2022
- Type: Text , Journal article
- Relation: Plants Vol. 11, no. 23 (2022), p.
- Full Text:
- Reviewed:
- Description: Cyperus aromaticus (Navua sedge) is a problematic perennial weed in pastures and crops including sugarcane, banana, rice, and fruits and vegetables in tropical climates. It reproduces both via rhizomes and seeds. As a regenerative and storage organ, these rhizomes play an important part in the invasion, establishment, and persistence of this weed. To eliminate their regenerative ability, it is important to understand the regrowth potential with respect to rhizome fragment size and burial depth. This study evaluated the emergence of C. aromaticus from rhizomes in a controlled condition. Three different sizes of rhizome fragments were buried at seven depths of up to 20 cm in two soil types. The experimental measurements included (i) the time for tillers to emerge, (ii) the cumulative emergence of tillers, recorded weekly, and (iii) the number of underground emerging tillers. The cumulative shoot emergence and the number of underground tillers produced were found to be positively correlated with the initial length of the rhizome fragments and negatively correlated with the burial depth. The time for the emergence of the tillers was negatively correlated with the burial depth, and soil type had no significant effect on any of the parameters recorded. There was no emergence recorded from rhizomes buried at 15 cm depth and deeper, irrespective of their size. Our results indicate that the combination of the fragmentation of rhizomes into small pieces and a deep burial, below 15 cm, is an important aspect to control the regeneration of C. aromaticus from rhizomes, if tillage is carried out, and can therefore form a part of an integrated weed management strategy for this troublesome weed. © 2022 by the authors.
Effects on photosynthetic response and biomass productivity of acacia longifolia ssp. longifolia under elevated CO2 and water-limited regimes
- Javaid, Muhammad, Wang, Xiukang, Florentine, Singarayer, Ashraf, Muhammad, Mahmood, Athar, Li, Feng-Min, Fiaz, Sajid
- Authors: Javaid, Muhammad , Wang, Xiukang , Florentine, Singarayer , Ashraf, Muhammad , Mahmood, Athar , Li, Feng-Min , Fiaz, Sajid
- Date: 2022
- Type: Text , Journal article
- Relation: Frontiers in Plant Science Vol. 13, no. (2022), p.
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- Description: It is known that the impact of elevated CO2 (eCO2) will cause differential photosynthetic responses in plants, resulting in varying magnitudes of growth and productivity of competing species. Because of the aggressive invasive nature of Acacia longifolia ssp. longifolia, this study is designed to investigate the effect of eCO2 on gas exchange parameters, water use efficiency, photosystem II (PSII) activities, and growth of this species. Plants of A. longifolia ssp. longifolia were grown at 400 ppm (ambient) and 700 ppm (elevated) CO2 under 100 and 60% field capacity. Leaf gas exchange parameters, water use efficiency, intrinsic water use efficiency, instantaneous carboxylation efficiency, and PSII activity were measured for 10 days at 2-day intervals. eCO2 mitigated the adverse effects of drought conditions on the aforementioned parameters compared to that grown under ambient CO2 (aCO2) conditions. A. longifolia, grown under drought conditions and re-watered at day 8, indicated a partial recovery in most of the parameters measured, suggesting that the recovery of this species under eCO2 will be higher than that with aCO2 concentration. This gave an increase in water use efficiency, which is one of the reasons for the observed enhanced growth of A. longifolia under drought stress. Thus, eCO2 will allow to adopt this species in the new environment, even under severe climatic conditions, and foreshadow its likelihood of invasion into new areas. Copyright © 2022 Javaid, Wang, Florentine, Ashraf, Mahmood, Li and Fiaz.
- Authors: Javaid, Muhammad , Wang, Xiukang , Florentine, Singarayer , Ashraf, Muhammad , Mahmood, Athar , Li, Feng-Min , Fiaz, Sajid
- Date: 2022
- Type: Text , Journal article
- Relation: Frontiers in Plant Science Vol. 13, no. (2022), p.
- Full Text:
- Reviewed:
- Description: It is known that the impact of elevated CO2 (eCO2) will cause differential photosynthetic responses in plants, resulting in varying magnitudes of growth and productivity of competing species. Because of the aggressive invasive nature of Acacia longifolia ssp. longifolia, this study is designed to investigate the effect of eCO2 on gas exchange parameters, water use efficiency, photosystem II (PSII) activities, and growth of this species. Plants of A. longifolia ssp. longifolia were grown at 400 ppm (ambient) and 700 ppm (elevated) CO2 under 100 and 60% field capacity. Leaf gas exchange parameters, water use efficiency, intrinsic water use efficiency, instantaneous carboxylation efficiency, and PSII activity were measured for 10 days at 2-day intervals. eCO2 mitigated the adverse effects of drought conditions on the aforementioned parameters compared to that grown under ambient CO2 (aCO2) conditions. A. longifolia, grown under drought conditions and re-watered at day 8, indicated a partial recovery in most of the parameters measured, suggesting that the recovery of this species under eCO2 will be higher than that with aCO2 concentration. This gave an increase in water use efficiency, which is one of the reasons for the observed enhanced growth of A. longifolia under drought stress. Thus, eCO2 will allow to adopt this species in the new environment, even under severe climatic conditions, and foreshadow its likelihood of invasion into new areas. Copyright © 2022 Javaid, Wang, Florentine, Ashraf, Mahmood, Li and Fiaz.
Evaluation of Florpyrauxifen-Benzyl for the control of Cyperus aromaticus (Navua sedge)
- Chadha, Aakansha, Florentine, Singarayer, Dhileepan, Kunjithapatham, Turville, Chris, Dowling, Kim
- Authors: Chadha, Aakansha , Florentine, Singarayer , Dhileepan, Kunjithapatham , Turville, Chris , Dowling, Kim
- Date: 2022
- Type: Text , Journal article
- Relation: Advances in Weed Science Vol. 40, no. (2022), p.
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- Description: Background: Cyperus aromaticus (Navua sedge) is a creeping perennial sedge common to tropical environments, currently threatening many agroecosystems and ecosystems in Pacific Island countries and northern Queensland in Australia. Objective: A glasshouse study was conducted to evaluate the efficacy of florpyrauxifen-benzyl on C. aromaticus plants with and without established rhizomes. Methods: The plants with established rhizomes were treated at three application times being mowed, pre-flowering and flowering growth stages and plants without established rhizomes were treated at seedling, pre-flowering and flowering growth stages. At each application time, plants were treated with four rates of florpyrauxifen-benzyl: 0, 15, 30 and 60 g a.i. ha-1 and control. Results: There was no mortality in the plants with established rhizomes. Reduction in the number of tillers was observed at four weeks after treatment (WAT) in plants treated with 30 and 60 g a.i. ha-1 of herbicide, however, there was new growth from the rhizomes and the number of tillers increased at 8 WAT. Conversely, florpyrauxifen-benzyl provided above 95% control in plants without established rhizomes. Conclusions: These results indicate florpyrauxifen-benzyl can help manage a new C. aromaticus infestation prior to the establishment of rhizomes. However, it has little to no impact on C. aromaticus plants with established rhizomes, and other management options should be employed to control them. © 2022, Sociedade Brasileira da Ciencia das Plantas Daninha. All rights reserved.
- Authors: Chadha, Aakansha , Florentine, Singarayer , Dhileepan, Kunjithapatham , Turville, Chris , Dowling, Kim
- Date: 2022
- Type: Text , Journal article
- Relation: Advances in Weed Science Vol. 40, no. (2022), p.
- Full Text:
- Reviewed:
- Description: Background: Cyperus aromaticus (Navua sedge) is a creeping perennial sedge common to tropical environments, currently threatening many agroecosystems and ecosystems in Pacific Island countries and northern Queensland in Australia. Objective: A glasshouse study was conducted to evaluate the efficacy of florpyrauxifen-benzyl on C. aromaticus plants with and without established rhizomes. Methods: The plants with established rhizomes were treated at three application times being mowed, pre-flowering and flowering growth stages and plants without established rhizomes were treated at seedling, pre-flowering and flowering growth stages. At each application time, plants were treated with four rates of florpyrauxifen-benzyl: 0, 15, 30 and 60 g a.i. ha-1 and control. Results: There was no mortality in the plants with established rhizomes. Reduction in the number of tillers was observed at four weeks after treatment (WAT) in plants treated with 30 and 60 g a.i. ha-1 of herbicide, however, there was new growth from the rhizomes and the number of tillers increased at 8 WAT. Conversely, florpyrauxifen-benzyl provided above 95% control in plants without established rhizomes. Conclusions: These results indicate florpyrauxifen-benzyl can help manage a new C. aromaticus infestation prior to the establishment of rhizomes. However, it has little to no impact on C. aromaticus plants with established rhizomes, and other management options should be employed to control them. © 2022, Sociedade Brasileira da Ciencia das Plantas Daninha. All rights reserved.
Interactive effect of elevated CO2 and drought on physiological traits of Datura stramonium
- Javaid, Muhammad, Florentine, Singarayer, Mahmood, Athar, Wasaya, Allah, Javed, Talha, Sattar, Abdul, Sarwar, Naeem, Kalaji, Hazem, Ahmad, Hafiz, Worbel, Jacek, Ahmed, Mohammed, Telesiński, Arkadiusz, Mojski, Jacek
- Authors: Javaid, Muhammad , Florentine, Singarayer , Mahmood, Athar , Wasaya, Allah , Javed, Talha , Sattar, Abdul , Sarwar, Naeem , Kalaji, Hazem , Ahmad, Hafiz , Worbel, Jacek , Ahmed, Mohammed , Telesiński, Arkadiusz , Mojski, Jacek
- Date: 2022
- Type: Text , Journal article
- Relation: Frontiers in Plant Science Vol. 13, no. (2022), p.
- Full Text:
- Reviewed:
- Description: Rising atmospheric CO2 concentrations are known to influence the response of many plants under drought. This paper aimed to measure the leaf gas exchange, water use efficiency, carboxylation efficiency, and photosystem II (PS II) activity of Datura stramonium under progressive drought conditions, along with ambient conditions of 400 ppm (aCO2) and elevated conditions of 700 ppm (eCO2). Plants of D. stramonium were grown at 400 ppm and 700 ppm under 100 and 60% field capacity in a laboratory growth chamber. For 10 days at two-day intervals, photosynthesis rate, stomatal conductance, transpiration rate, intercellular CO2 concentration, water use efficiency, intrinsic water use efficiency, instantaneous carboxylation efficiency, PSII activity, electron transport rate, and photochemical quenching were measured. While drought stress had generally negative effects on the aforementioned physiological traits of D. stramonium, it was found that eCO2 concentration mitigated the adverse effects of drought and most of the physiological parameters were sustained with increasing drought duration when compared to that with aCO2. D. stramonium, which was grown under drought conditions, was re-watered on day 8 and indicated a partial recovery in all the parameters except maximum fluorescence, with this recovery being higher with eCO2 compared to aCO2. These results suggest that elevated CO2 mitigates the adverse growth effects of drought, thereby enhancing the adaptive mechanism of this weed by improving its water use efficiency. It is concluded that this weed has the potential to take advantage of climate change by increasing its competitiveness with other plants in drought-prone areas, suggesting that it could expand into new localities. Copyright © 2022 Javaid, Florentine, Mahmood, Wasaya, Javed, Sattar, Sarwar, Kalaji, Ahmad, Worbel, Ahmed, Telesiński and Mojski.
- Authors: Javaid, Muhammad , Florentine, Singarayer , Mahmood, Athar , Wasaya, Allah , Javed, Talha , Sattar, Abdul , Sarwar, Naeem , Kalaji, Hazem , Ahmad, Hafiz , Worbel, Jacek , Ahmed, Mohammed , Telesiński, Arkadiusz , Mojski, Jacek
- Date: 2022
- Type: Text , Journal article
- Relation: Frontiers in Plant Science Vol. 13, no. (2022), p.
- Full Text:
- Reviewed:
- Description: Rising atmospheric CO2 concentrations are known to influence the response of many plants under drought. This paper aimed to measure the leaf gas exchange, water use efficiency, carboxylation efficiency, and photosystem II (PS II) activity of Datura stramonium under progressive drought conditions, along with ambient conditions of 400 ppm (aCO2) and elevated conditions of 700 ppm (eCO2). Plants of D. stramonium were grown at 400 ppm and 700 ppm under 100 and 60% field capacity in a laboratory growth chamber. For 10 days at two-day intervals, photosynthesis rate, stomatal conductance, transpiration rate, intercellular CO2 concentration, water use efficiency, intrinsic water use efficiency, instantaneous carboxylation efficiency, PSII activity, electron transport rate, and photochemical quenching were measured. While drought stress had generally negative effects on the aforementioned physiological traits of D. stramonium, it was found that eCO2 concentration mitigated the adverse effects of drought and most of the physiological parameters were sustained with increasing drought duration when compared to that with aCO2. D. stramonium, which was grown under drought conditions, was re-watered on day 8 and indicated a partial recovery in all the parameters except maximum fluorescence, with this recovery being higher with eCO2 compared to aCO2. These results suggest that elevated CO2 mitigates the adverse growth effects of drought, thereby enhancing the adaptive mechanism of this weed by improving its water use efficiency. It is concluded that this weed has the potential to take advantage of climate change by increasing its competitiveness with other plants in drought-prone areas, suggesting that it could expand into new localities. Copyright © 2022 Javaid, Florentine, Mahmood, Wasaya, Javed, Sattar, Sarwar, Kalaji, Ahmad, Worbel, Ahmed, Telesiński and Mojski.
Photosynthetic activity and water use efficiency of Salvia verbenaca L. under elevated CO2 and water‐deficit conditions
- Javaid, Muhammad Mansoor, Florentine, Singarayer, Ashraf, Muhammad, Mahmood, Athar, Sattar, Abdul, Wasaya, Allah, Li, Feng‐Min
- Authors: Javaid, Muhammad Mansoor , Florentine, Singarayer , Ashraf, Muhammad , Mahmood, Athar , Sattar, Abdul , Wasaya, Allah , Li, Feng‐Min
- Date: 2022
- Type: Text , Journal article
- Relation: Journal of agronomy and crop science Vol. 208, no. 4 (2022), p. 536-551
- Full Text:
- Reviewed:
- Description: Investigating the combined effects of elevated CO2 concentration and water‐deficit on weed plants is crucial to gaining a thorough understanding of plant performance and modifying agricultural processes under changing climate conditions. This study examined the effect of elevated CO2 concentration and water‐deficit conditions on leaf gas exchange, water use efficiency, carboxylation efficiency and the photosystem II (PSII) activity of two Salvia verbenaca L., varieties. These varieties were grown under two CO2 concentrations (ambient conditions of 400 ppm and elevated conditions of 700 ppm) and two water regimes (well‐watered [100% field capacity] and water‐deficit conditions [60% field capacity]) in laboratory growth chambers. For 12 days, at 2‐day intervals, (i) leaf gas exchange parameters (photosynthesis rate, stomatal conductance, transpiration rate (E) and intercellular CO2 concentration (Ci)), (ii) water use efficiency (WUE), (iii) intrinsic water use efficiency (IWUE), (iv) instantaneous carboxylation efficiency and (v) PSII activity (fluorescence, quantum yield of PSII, photochemical efficiency of PSII, photochemical quenching and photosynthetic electron transport) were measured. Water‐deficit conditions had negative effects on studied parameters of both varieties, whereas elevated CO2 concentration had positive effects on the gas exchange, water use efficiency and PSII activity of both. Salvia verbenaca varieties grown under water‐deficit conditions from Day 0 to Day 5 showed a partial recovery in most of the parameters when the resumption of the well‐watered regime was reinstituted on Day 6. Salvia verbenaca varieties grown under water‐deficit conditions were re‐watered on day 6 and indicated a partial recovery in all the parameters. A comparison of the two varieties showed that var. vernalis recorded higher values of gas exchange, quantum yield of PSII and photochemical efficiency of PSII than var. verbenaca, but the water use efficiency of var. verbenaca was higher than that of var. vernalis. These differences serve to illustrate the complexity of such studies and suggest that a detailed understanding of the nature of weed infestations is essential if optimum management control is to be practiced. Elevated CO2 concentration mitigated the adverse effects of water‐deficit conditions and thereby enhanced the adaptive mechanism of this weed by improving its water use efficiency. It is thus likely that S. verbenaca has the potential to take advantage of climate change by increasing its relative competitiveness with other plants in drought‐prone areas, suggesting that it could significantly expand its invasive range under such conditions.
- Authors: Javaid, Muhammad Mansoor , Florentine, Singarayer , Ashraf, Muhammad , Mahmood, Athar , Sattar, Abdul , Wasaya, Allah , Li, Feng‐Min
- Date: 2022
- Type: Text , Journal article
- Relation: Journal of agronomy and crop science Vol. 208, no. 4 (2022), p. 536-551
- Full Text:
- Reviewed:
- Description: Investigating the combined effects of elevated CO2 concentration and water‐deficit on weed plants is crucial to gaining a thorough understanding of plant performance and modifying agricultural processes under changing climate conditions. This study examined the effect of elevated CO2 concentration and water‐deficit conditions on leaf gas exchange, water use efficiency, carboxylation efficiency and the photosystem II (PSII) activity of two Salvia verbenaca L., varieties. These varieties were grown under two CO2 concentrations (ambient conditions of 400 ppm and elevated conditions of 700 ppm) and two water regimes (well‐watered [100% field capacity] and water‐deficit conditions [60% field capacity]) in laboratory growth chambers. For 12 days, at 2‐day intervals, (i) leaf gas exchange parameters (photosynthesis rate, stomatal conductance, transpiration rate (E) and intercellular CO2 concentration (Ci)), (ii) water use efficiency (WUE), (iii) intrinsic water use efficiency (IWUE), (iv) instantaneous carboxylation efficiency and (v) PSII activity (fluorescence, quantum yield of PSII, photochemical efficiency of PSII, photochemical quenching and photosynthetic electron transport) were measured. Water‐deficit conditions had negative effects on studied parameters of both varieties, whereas elevated CO2 concentration had positive effects on the gas exchange, water use efficiency and PSII activity of both. Salvia verbenaca varieties grown under water‐deficit conditions from Day 0 to Day 5 showed a partial recovery in most of the parameters when the resumption of the well‐watered regime was reinstituted on Day 6. Salvia verbenaca varieties grown under water‐deficit conditions were re‐watered on day 6 and indicated a partial recovery in all the parameters. A comparison of the two varieties showed that var. vernalis recorded higher values of gas exchange, quantum yield of PSII and photochemical efficiency of PSII than var. verbenaca, but the water use efficiency of var. verbenaca was higher than that of var. vernalis. These differences serve to illustrate the complexity of such studies and suggest that a detailed understanding of the nature of weed infestations is essential if optimum management control is to be practiced. Elevated CO2 concentration mitigated the adverse effects of water‐deficit conditions and thereby enhanced the adaptive mechanism of this weed by improving its water use efficiency. It is thus likely that S. verbenaca has the potential to take advantage of climate change by increasing its relative competitiveness with other plants in drought‐prone areas, suggesting that it could significantly expand its invasive range under such conditions.
Soil seed bank dynamics of pastures invaded by navua sedge (cyperus aromaticus) in tropical north Queensland
- Chadha, Aakansha, Osunkoya, Olusegun, Shi, Boyang, Florentine, Singarayer, Dhileepan, Kunjithapatham
- Authors: Chadha, Aakansha , Osunkoya, Olusegun , Shi, Boyang , Florentine, Singarayer , Dhileepan, Kunjithapatham
- Date: 2022
- Type: Journal article
- Relation: Frontiers in agronomy Vol. 4, no. (2022), p.
- Full Text:
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- Description: Navua sedge (Cyperus aromaticus) is threatening crops, pasture species and natural ecosystems in Pacific Island countries and northern Queensland, Australia. To aid future management efforts of this exotic invasive weed, research was conducted to understand the soil seed bank dynamics of pastures invaded by Navua sedge. Six grazing properties were chosen across two landscapes, coastal and inland/upland, with areas that had Navua sedge infestations in Queensland, Australia. At each site, soil was collected from two soil depths, 0-5 and 5-10 cm, and from plots with high and low infestation levels of Navua sedge. It was observed that the soil seed bank dynamics varied significantly between these study sites. Navua sedge was the dominant species in the soil seed bank at all the sites contributing between 62% to 95% of the total seed bank, while pasture seeds occupied only 3% to 24%. Broadleaf seeds were even lower in abundance, showing between 2% to 13% of the total seed count. The abundance of Navua sedge seed present in the soil was significantly correlated with the aboveground biomass of Navua sedge (r=0.53, p=0.006), but no correlation was found with the infestation age of Navua sedge. Based on this work, it is clear that the seed bank of Navua sedge is very large and concentrated within the top 0-5 cm of the soil, with, 83% of total Navua sedge seeds being in this layer. It was also noted that, although, high infestation plots had significantly higher number of seeds than low infestation plots, more than 18,000 Navua sedge seeds/m 2 were still found in the 0-5 cm soil layer of plots regarded as low infestation. We suggest that insights achieved from our soil seed bank study may be used to devise management strategies to minimise the impact of Navua sedge weed in critical grazing and agricultural areas.
- Authors: Chadha, Aakansha , Osunkoya, Olusegun , Shi, Boyang , Florentine, Singarayer , Dhileepan, Kunjithapatham
- Date: 2022
- Type: Journal article
- Relation: Frontiers in agronomy Vol. 4, no. (2022), p.
- Full Text:
- Reviewed:
- Description: Navua sedge (Cyperus aromaticus) is threatening crops, pasture species and natural ecosystems in Pacific Island countries and northern Queensland, Australia. To aid future management efforts of this exotic invasive weed, research was conducted to understand the soil seed bank dynamics of pastures invaded by Navua sedge. Six grazing properties were chosen across two landscapes, coastal and inland/upland, with areas that had Navua sedge infestations in Queensland, Australia. At each site, soil was collected from two soil depths, 0-5 and 5-10 cm, and from plots with high and low infestation levels of Navua sedge. It was observed that the soil seed bank dynamics varied significantly between these study sites. Navua sedge was the dominant species in the soil seed bank at all the sites contributing between 62% to 95% of the total seed bank, while pasture seeds occupied only 3% to 24%. Broadleaf seeds were even lower in abundance, showing between 2% to 13% of the total seed count. The abundance of Navua sedge seed present in the soil was significantly correlated with the aboveground biomass of Navua sedge (r=0.53, p=0.006), but no correlation was found with the infestation age of Navua sedge. Based on this work, it is clear that the seed bank of Navua sedge is very large and concentrated within the top 0-5 cm of the soil, with, 83% of total Navua sedge seeds being in this layer. It was also noted that, although, high infestation plots had significantly higher number of seeds than low infestation plots, more than 18,000 Navua sedge seeds/m 2 were still found in the 0-5 cm soil layer of plots regarded as low infestation. We suggest that insights achieved from our soil seed bank study may be used to devise management strategies to minimise the impact of Navua sedge weed in critical grazing and agricultural areas.
The Angiosperm Stem Hemiparasitic Genus Cassytha (Lauraceae) and its host interactions : a review
- Zhang, Hongxiang, Florentine, Singarayer, Tennakoon, Kushan
- Authors: Zhang, Hongxiang , Florentine, Singarayer , Tennakoon, Kushan
- Date: 2022
- Type: Text , Journal article , Review
- Relation: Frontiers in Plant Science Vol. 13, no. (2022), p.
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- Description: Cassytha, also known as laurel dodder or love vine, is a stem hemiparasite of the Lauraceae family. It has long been used for medicinal purposes in many countries and has increasingly influenced agricultural and natural ecosystems by its effects on a wide range of host species. Previous studies have focused on the taxonomy and evolutionary position of different Cassytha, with the pan-tropical species Cassytha filiformis being the most widely studied. However, Cassytha–host interactions have never been reviewed, which is an essential issue related to the understanding of mechanisms underlying plant hemiparasitic and the assessment of benefits and damage caused by aerial parasitic plants. This review explores the parasitic habits, worldwide distribution, and host range of Cassytha, and examines its impacts on the biology of host plants and the overall influence of environmental changes on Cassytha–host associations. We also comment on areas of future research directions that require to better understanding Cassytha–host interactions. It appeared that some traits, such as flowering phenology, facilitated Cassytha’s widespread distribution and successful parasitism and that Cassytha preferred woody species rather than herbaceous species as a host, and preferred species from certain families as hosts, such as Fabaceae and Myrtaceae. Cassytha often decreased biomass and impacted the physiology of host species and global environmental changes seemed to intensify the negative impacts of Cassytha on their hosts. Cassytha was not only a noxious weed, but can also function as a biocontrol agent to mitigate alien plant invasion. Copyright © 2022 Zhang, Florentine and Tennakoon.
- Authors: Zhang, Hongxiang , Florentine, Singarayer , Tennakoon, Kushan
- Date: 2022
- Type: Text , Journal article , Review
- Relation: Frontiers in Plant Science Vol. 13, no. (2022), p.
- Full Text:
- Reviewed:
- Description: Cassytha, also known as laurel dodder or love vine, is a stem hemiparasite of the Lauraceae family. It has long been used for medicinal purposes in many countries and has increasingly influenced agricultural and natural ecosystems by its effects on a wide range of host species. Previous studies have focused on the taxonomy and evolutionary position of different Cassytha, with the pan-tropical species Cassytha filiformis being the most widely studied. However, Cassytha–host interactions have never been reviewed, which is an essential issue related to the understanding of mechanisms underlying plant hemiparasitic and the assessment of benefits and damage caused by aerial parasitic plants. This review explores the parasitic habits, worldwide distribution, and host range of Cassytha, and examines its impacts on the biology of host plants and the overall influence of environmental changes on Cassytha–host associations. We also comment on areas of future research directions that require to better understanding Cassytha–host interactions. It appeared that some traits, such as flowering phenology, facilitated Cassytha’s widespread distribution and successful parasitism and that Cassytha preferred woody species rather than herbaceous species as a host, and preferred species from certain families as hosts, such as Fabaceae and Myrtaceae. Cassytha often decreased biomass and impacted the physiology of host species and global environmental changes seemed to intensify the negative impacts of Cassytha on their hosts. Cassytha was not only a noxious weed, but can also function as a biocontrol agent to mitigate alien plant invasion. Copyright © 2022 Zhang, Florentine and Tennakoon.
Effect of selected environmental factors on the seed germination of the invasive species Polygala myrtifolia (Polygalaceae) in Australia
- Roberts, Natalie, Moloney, Katrina, Monie, Kristin, Florentine, Singarayer
- Authors: Roberts, Natalie , Moloney, Katrina , Monie, Kristin , Florentine, Singarayer
- Date: 2023
- Type: Text , Journal article
- Relation: Australian Journal of Botany Vol. 71, no. 6 (2023), p. 286-295
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- Description: Context. Polygala myrtifolia L. has become a significant environmental weed in Australia, where it has invaded coastal ecosystems in temperate regions and there is a high risk of extensive further spread. Knowledge of seed-germination behaviour is essential to understand the potential future impact of this species. Aims. We investigated the effects of selected environmental factors and dormancy on P. myrtifolia seed germination and emergence to improve management strategies. Methods. Seeds were exposed to light, temperature, pH, salinity, osmotic potential and burial depth treatments to assess germination responses, dormancy and viability. Key results. Non-dormant seeds readily germinated to high percentages (93.0–95.0%) under specific day–night temperatures of 25°C–15°C regardless of light conditions and across all soil pH (75.0–100.0%). Salinities were tolerated up to 100 mM NaCl (70.0% germination) before sharply declining. Germination reduced from 98.3% to 40.0% at osmotic potentials of
- Authors: Roberts, Natalie , Moloney, Katrina , Monie, Kristin , Florentine, Singarayer
- Date: 2023
- Type: Text , Journal article
- Relation: Australian Journal of Botany Vol. 71, no. 6 (2023), p. 286-295
- Full Text:
- Reviewed:
- Description: Context. Polygala myrtifolia L. has become a significant environmental weed in Australia, where it has invaded coastal ecosystems in temperate regions and there is a high risk of extensive further spread. Knowledge of seed-germination behaviour is essential to understand the potential future impact of this species. Aims. We investigated the effects of selected environmental factors and dormancy on P. myrtifolia seed germination and emergence to improve management strategies. Methods. Seeds were exposed to light, temperature, pH, salinity, osmotic potential and burial depth treatments to assess germination responses, dormancy and viability. Key results. Non-dormant seeds readily germinated to high percentages (93.0–95.0%) under specific day–night temperatures of 25°C–15°C regardless of light conditions and across all soil pH (75.0–100.0%). Salinities were tolerated up to 100 mM NaCl (70.0% germination) before sharply declining. Germination reduced from 98.3% to 40.0% at osmotic potentials of
Exploring efficient techniques to decrease phosphorus levels in previously farmed land to promote the revival of indigenous grassland
- Shakir, Shakir, Florentine, Singarayer, Schultz, Nicholas
- Authors: Shakir, Shakir , Florentine, Singarayer , Schultz, Nicholas
- Date: 2023
- Type: Text , Journal article
- Relation: Passer Journal of Basic and Applied Sciences Vol. 5, no. 2 (2023), p. 371-376
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- Description: Restoration of native grasslands is challenging due to high soil phosphorus levels. Cultivation of plants with high phosphorus (P) absorption is an optimal solution to remove and decrease P from the soil. It has been demonstrated that native grassland taxa (species) of the genus Ptilotus have significant P-uptake. In a glasshouse study, Ptilotus macrocephalus and Ptilotus polystachyus were tested for their ability to reduce the amount of soil phosphorus that was readily available. Lupinus albus, a third species with a reputation for high phosphorus uptake, served as a comparison species, and a further treatment included Phoslock®, a soil additive that could bind soil phosphorus into insoluble forms. The findings revealed that phosphorus in the soil was absorbed at a high level via Ptilotus macrocephalus and Ptilotus polystachyus showed a maximum reduction of P (-2.58 and -2.55 ppm). It is argued that several years of planting and harvesting these plants will offer a workable method for lowering soil phosphorus levels. However, this only happened at high concentrations of 1500 g/m2 and when soil phosphorus concentrations were very high. Despite, the Phoslock®'s effectiveness in lowering soil-accessible phosphorus. At concentrations often observed in former agriculture paddocks, it proved less effective. The study's findings have improved our existing comprehension of reclaiming abandoned grassland. © 2023 Authors. All rights reserved.
- Authors: Shakir, Shakir , Florentine, Singarayer , Schultz, Nicholas
- Date: 2023
- Type: Text , Journal article
- Relation: Passer Journal of Basic and Applied Sciences Vol. 5, no. 2 (2023), p. 371-376
- Full Text:
- Reviewed:
- Description: Restoration of native grasslands is challenging due to high soil phosphorus levels. Cultivation of plants with high phosphorus (P) absorption is an optimal solution to remove and decrease P from the soil. It has been demonstrated that native grassland taxa (species) of the genus Ptilotus have significant P-uptake. In a glasshouse study, Ptilotus macrocephalus and Ptilotus polystachyus were tested for their ability to reduce the amount of soil phosphorus that was readily available. Lupinus albus, a third species with a reputation for high phosphorus uptake, served as a comparison species, and a further treatment included Phoslock®, a soil additive that could bind soil phosphorus into insoluble forms. The findings revealed that phosphorus in the soil was absorbed at a high level via Ptilotus macrocephalus and Ptilotus polystachyus showed a maximum reduction of P (-2.58 and -2.55 ppm). It is argued that several years of planting and harvesting these plants will offer a workable method for lowering soil phosphorus levels. However, this only happened at high concentrations of 1500 g/m2 and when soil phosphorus concentrations were very high. Despite, the Phoslock®'s effectiveness in lowering soil-accessible phosphorus. At concentrations often observed in former agriculture paddocks, it proved less effective. The study's findings have improved our existing comprehension of reclaiming abandoned grassland. © 2023 Authors. All rights reserved.
Potential contributions of the soil seed bank and seed rain for accelerating the restoration of riparian catchments in Australia
- Florentine, Singarayer, Milberg, Per, Westbrooke, Martin
- Authors: Florentine, Singarayer , Milberg, Per , Westbrooke, Martin
- Date: 2023
- Type: Text , Journal article
- Relation: Global Ecology and Conservation Vol. 47, no. (2023), p.
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- Description: The quality and quantity of soil seed bank composition can play a key role in secondary succession restoration efforts such as those involved in this study, which concerned the restoration of damaged native sites in riparian environments in Victoria, Australia. The objective of this study of the restoration work was to determine the role played by naturally existing soil seed bank in the success of natural restoration in these restored and unmanaged riparian areas. In this regard, we sampled the soil seed bank, seed rain, seedlings in the field and vegetation cover from three sub catchments defined by restoration attempts which had been conducted (i) < 3 years, (ii) 4–8 years, and (iii) > 9 years previous to sampling. In addition, (iv) in order to provide comparative data, adjacent sites (iv) chosen for future restoration and (v) with remnant vegetation, were also sampled. From samples, a total of 8858 seedlings were recorded from the seed bank and the vegetation survey showed 170 species, with exotic species being more numerous than native. The seed rain (a total of 1422 seeds) was dominated by exotic species at all sites. When comparing the vegetation distribution and the seed rain composition, it was clear that whilst the seed bank was more promising as a comparative recruitment source of native species, there were still too many sites dominated by exotic species to rely on this as a long-term restoration strategy. However, this study indicated that there were significant variations in restoration potential among the sites, suggesting that some careful prior site selection for investment of restoration efforts is an important issue. As a consequence, we have recommended that a detailed understanding of the soil seed bank and seed rain species composition prior to the restoration is essential, since a positive seed bank composition with a significant relative density of native species seeds, will provide an indication of native species’ resilience and their potential for recovery. We therefore believe that the findings of this study will provide valuable information to natural resource management agencies regarding the strategy for prioritisation of restoration sites, which will be more beneficial than randomly selecting sites for habitat restoration. In addition, with successful sector restoration, it is expected that the increasing usefulness of the seed bank will allow further restoration of adjacent areas with time. © 2023 The Authors
- Authors: Florentine, Singarayer , Milberg, Per , Westbrooke, Martin
- Date: 2023
- Type: Text , Journal article
- Relation: Global Ecology and Conservation Vol. 47, no. (2023), p.
- Full Text:
- Reviewed:
- Description: The quality and quantity of soil seed bank composition can play a key role in secondary succession restoration efforts such as those involved in this study, which concerned the restoration of damaged native sites in riparian environments in Victoria, Australia. The objective of this study of the restoration work was to determine the role played by naturally existing soil seed bank in the success of natural restoration in these restored and unmanaged riparian areas. In this regard, we sampled the soil seed bank, seed rain, seedlings in the field and vegetation cover from three sub catchments defined by restoration attempts which had been conducted (i) < 3 years, (ii) 4–8 years, and (iii) > 9 years previous to sampling. In addition, (iv) in order to provide comparative data, adjacent sites (iv) chosen for future restoration and (v) with remnant vegetation, were also sampled. From samples, a total of 8858 seedlings were recorded from the seed bank and the vegetation survey showed 170 species, with exotic species being more numerous than native. The seed rain (a total of 1422 seeds) was dominated by exotic species at all sites. When comparing the vegetation distribution and the seed rain composition, it was clear that whilst the seed bank was more promising as a comparative recruitment source of native species, there were still too many sites dominated by exotic species to rely on this as a long-term restoration strategy. However, this study indicated that there were significant variations in restoration potential among the sites, suggesting that some careful prior site selection for investment of restoration efforts is an important issue. As a consequence, we have recommended that a detailed understanding of the soil seed bank and seed rain species composition prior to the restoration is essential, since a positive seed bank composition with a significant relative density of native species seeds, will provide an indication of native species’ resilience and their potential for recovery. We therefore believe that the findings of this study will provide valuable information to natural resource management agencies regarding the strategy for prioritisation of restoration sites, which will be more beneficial than randomly selecting sites for habitat restoration. In addition, with successful sector restoration, it is expected that the increasing usefulness of the seed bank will allow further restoration of adjacent areas with time. © 2023 The Authors
The response of Nassella trichotoma (serrated tussock) seeds and seedlings to different levels of fire intensity
- Humphries, Talia, Florentine, Singarayer
- Authors: Humphries, Talia , Florentine, Singarayer
- Date: 2023
- Type: Text , Journal article
- Relation: Australian Journal of Botany Vol. 71, no. 4 (2023), p. 188-198
- Full Text:
- Reviewed:
- Description: Context Fire is an important disturbance regime in grassland communities, since it is responsible for stimulating the regeneration of many species and for maintaining levels of biodiversity. When invasive plants, such as Nassella trichotoma, establish and become widespread in a grassland community, these important fire events can be altered in intensity and frequency, which means that they are able to facilitate the establishment of the exotic species. Therefore, before fire can be recommended as a suitable control technique for invasive species, or alternatively to be integrated into grassland restoration programs, understanding the response of the seeds of exotic species to high temperatures, such as those experienced during a fire, should be well understood. Aims Our aim was to identify their response to a gradient of temperatures associated with different levels of fire intensity. We examined how increased duration of exposure affects their response, and whether seed age or seed moisture content affect the germination response of this species. Methods To gain a fuller understanding of the fire response of N. trichotoma’s seedbank, seeds were collected in 2016, 2017, 2018 and 2019 and then stored until the commencement of the experiments in 2020. Selected seeds were first subjected to an increasing temperature gradient (80°C, 100°C, 120°C, 140°C, and a control), and an increasing duration of exposure (of 1, 3, 6, and 9 min). In the second experiment, one population was selected to test these same temperatures and duration of exposure after the seeds were hydrated to 15%, 50%, or 95%. Last, seedlings were grown for 3 months under glasshouse conditions and then exposed to increasing temperatures (20°C, 60°C, 80°C, 100°C, and 120°C), and an increasing duration of exposure (3, 6, and 9 min). The seedlings were assessed 2 weeks after the heat exposure for signs of damage. Key results It was found that increased temperatures and duration of exposure had a subtle negative effect on germination parameters, including reduced total germination and increased time to 50% germination. The 140°C treatment was seen to be a significant threshold because it killed all the seeds at any duration of exposure. A significant difference among the ages of each seed lot was observed to be a factor on the tested germination metrics, with the oldest tested population (2016) demonstrating the highest germination percentage, uniformity, and rate. Seed germination percentage was significantly reduced for seeds hydrated to 95% compared with the control treatment, whereas no significant difference was observed for the seeds hydrated to 15% and 50%. For the heat treatment of the seedlings, damage to the leaves was observed in the 80°C, 100°C, and 120°C treatments, with some plants in the 120°C treatment experiencing extensive damage prior to resprouting. No seedlings were killed at the tested temperatures. Conclusions Results of this study indicated that fire may be a useful tool for reducing seedbank density by killing a high proportion of the seeds on the soil surface, or located within the top 1 cm of the soil profile, but not for seeds buried more deeply. Efficacy of fire on surface and shallow-buried seeds is improved with high seed moisture content however, these seeds buried below this depth are still protected by the soil from the lethal effects of temperature. Implications Fire implemented before seed set could be used to effectively kill a large proportion of N. trichotoma seeds. However, for more comprehensive control, it is recommended that chemical treatment is integrated with the fire treatment to improve the overall control efficiency.
- Authors: Humphries, Talia , Florentine, Singarayer
- Date: 2023
- Type: Text , Journal article
- Relation: Australian Journal of Botany Vol. 71, no. 4 (2023), p. 188-198
- Full Text:
- Reviewed:
- Description: Context Fire is an important disturbance regime in grassland communities, since it is responsible for stimulating the regeneration of many species and for maintaining levels of biodiversity. When invasive plants, such as Nassella trichotoma, establish and become widespread in a grassland community, these important fire events can be altered in intensity and frequency, which means that they are able to facilitate the establishment of the exotic species. Therefore, before fire can be recommended as a suitable control technique for invasive species, or alternatively to be integrated into grassland restoration programs, understanding the response of the seeds of exotic species to high temperatures, such as those experienced during a fire, should be well understood. Aims Our aim was to identify their response to a gradient of temperatures associated with different levels of fire intensity. We examined how increased duration of exposure affects their response, and whether seed age or seed moisture content affect the germination response of this species. Methods To gain a fuller understanding of the fire response of N. trichotoma’s seedbank, seeds were collected in 2016, 2017, 2018 and 2019 and then stored until the commencement of the experiments in 2020. Selected seeds were first subjected to an increasing temperature gradient (80°C, 100°C, 120°C, 140°C, and a control), and an increasing duration of exposure (of 1, 3, 6, and 9 min). In the second experiment, one population was selected to test these same temperatures and duration of exposure after the seeds were hydrated to 15%, 50%, or 95%. Last, seedlings were grown for 3 months under glasshouse conditions and then exposed to increasing temperatures (20°C, 60°C, 80°C, 100°C, and 120°C), and an increasing duration of exposure (3, 6, and 9 min). The seedlings were assessed 2 weeks after the heat exposure for signs of damage. Key results It was found that increased temperatures and duration of exposure had a subtle negative effect on germination parameters, including reduced total germination and increased time to 50% germination. The 140°C treatment was seen to be a significant threshold because it killed all the seeds at any duration of exposure. A significant difference among the ages of each seed lot was observed to be a factor on the tested germination metrics, with the oldest tested population (2016) demonstrating the highest germination percentage, uniformity, and rate. Seed germination percentage was significantly reduced for seeds hydrated to 95% compared with the control treatment, whereas no significant difference was observed for the seeds hydrated to 15% and 50%. For the heat treatment of the seedlings, damage to the leaves was observed in the 80°C, 100°C, and 120°C treatments, with some plants in the 120°C treatment experiencing extensive damage prior to resprouting. No seedlings were killed at the tested temperatures. Conclusions Results of this study indicated that fire may be a useful tool for reducing seedbank density by killing a high proportion of the seeds on the soil surface, or located within the top 1 cm of the soil profile, but not for seeds buried more deeply. Efficacy of fire on surface and shallow-buried seeds is improved with high seed moisture content however, these seeds buried below this depth are still protected by the soil from the lethal effects of temperature. Implications Fire implemented before seed set could be used to effectively kill a large proportion of N. trichotoma seeds. However, for more comprehensive control, it is recommended that chemical treatment is integrated with the fire treatment to improve the overall control efficiency.