Background The intensive use of herbicides in agriculture raises concerns about their residual impacts on non-target crops such as cotton(Gossypium hirsutum L.),which is often rotated with cereals,sugar beet,and canol...Background The intensive use of herbicides in agriculture raises concerns about their residual impacts on non-target crops such as cotton(Gossypium hirsutum L.),which is often rotated with cereals,sugar beet,and canola.Butisanstar(BUT)and clopyralid(CLO)are widely used for broadleaf weed control in these rotations.However,how residual herbicide activity influences cotton growth and development is not well understood.This study evaluated these residual effects by measuring multiple growth parameters in a greenhouse.Cotton was grown for 40 days in soil incubated for 90 days with herbicide treatments arranged in a factorial design(type:BUT,CLO,and their combination;dose:0,1/2,1,2,and 5×recommended field dose[RFD]).Results Herbicide residues reduced cotton growth in a dose-dependent manner,with greater inhibition at higher doses.The combined BUT+CLO treatment produced the strongest negative effects,followed by CLO and then BUT alone.Compared with controls,seedling emergence declined by 12%–83%,root length by 12%–87%,plant height by 10%–84%,and chlorophyll index by 12%–80%across treatments from 1/2×RFD BUT to 5×RFD BUT+CLO.Root and shoot biomass also decreased significantly.Under the 5×RFD combined treatment,shoot N,P,and K concentrations dropped by 48%,78%,and 70%,respectively,relative to the control.Conclusions Even low levels of residual BUT and CLO impair cotton growth.To mitigate these effects,it should avoid planting cotton on recently treated soils,leave sufficient intervals between herbicide application and cotton planting,and apply soil amendments to boost microbial degradation.These measures are essential for sustaining soil health and cotton productivity.展开更多
The use of genetically modified organisms （GMOs） as food products becomes more and more widespread. The European Union has implemented a set of very strict procedures for the approval to grow, import and/or utilize ...The use of genetically modified organisms （GMOs） as food products becomes more and more widespread. The European Union has implemented a set of very strict procedures for the approval to grow, import and/or utilize GMOs as food or food ingredients. Thus, analytical methods for detection of GMOs are necessary in order to verify compliance with labelling requirements. There are few effective screening methods for processed GM （genetically modified） products. Three anti-herbicide genes （CP4- EPSPS, BAR and PAT） are common exogenous genes used in commercialized transgenic soybean, maize and rice, In the present study, a new SYBR Green qPCR screening method was developed to simultaneously detect the three exogenous anti-herbicide genes and one endogenous gene in a run. We tested seven samples of representative processed products （soya lecithin, soya protein powder, chocolate beverage, infant rice cereal, maize protein powder, maize starch, and maize jam） using the developed method, and amplicons of endogenous gene and transgenic fragments were obtained from all the processed products, and the sensitivity was 0.1%. These results indicated that SYBR Green qPCR screening method was appropriate for qualitative detection of transgenic soybean, maize and rice in processed products.展开更多
The resistance and cross-resistance of Scirpus juncoides Roxb.to ALS-inhibiting herbicides were tested to provide theoretical basis for effectively control Scirpus juncoides Roxb.and rational use of herbicides.To iden...The resistance and cross-resistance of Scirpus juncoides Roxb.to ALS-inhibiting herbicides were tested to provide theoretical basis for effectively control Scirpus juncoides Roxb.and rational use of herbicides.To identify the resistance and crossresistance of 19 populations from nine areas in Heilongjiang Province to four ALS-inhibiting herbicides by agar method and the whole-plant assay.The results are as the followings,the two bioassay methods had good correlation,the resistance indexes in the same area were different by two means,but resistant level was the same,similarity up to 89.5%.The resistant rates to pyrazosulfuronethyl,bensulfuron-methyl,penoxsulam and pyribenzoxim were 26.3%,36.8%,36.1%and 21.1%,respectively.Shangzhi populations evolved the highest level of resistance to pyrazosulfuron-methyl with a resistance index of 15.56.Shangzhi,Tonghe,Fangzheng and Jixi populations showed cross-resistance to four ALS-inhibiting herbicides,accounting for 26.3%.The resistance of Scirpus juncoides Roxb.to four ALS-inhibiting herbicides in Heilongjiang paddy field was low to moderate,five populations showed cross-resistance to four ALS-inhibiting herbicides.展开更多
This study examined the adoption of herbicides by arable farmers in Edo State. It assessed the proportion of arable farmers using herbicides, level of use and factors affecting adoption of herbicides. Simple random sa...This study examined the adoption of herbicides by arable farmers in Edo State. It assessed the proportion of arable farmers using herbicides, level of use and factors affecting adoption of herbicides. Simple random sampling was used to compose a sample size of 556 respondents. Various descriptive and inferential statistics were employed in data analyses. The results showed that onehalf of the respondents used herbicides(27.9% regularly using herbicides), and most of the adopters used non-selective herbicide. Avalanche of factors, including education attainment, farm size and farming experience also affected the adoption of herbicides.展开更多
The history, present status and future prospects of adjuvants application in herbicides were briefly reviewed. Adjuvants can be separated into two groups, activator adjuvants and utility adjuvants. The former directly...The history, present status and future prospects of adjuvants application in herbicides were briefly reviewed. Adjuvants can be separated into two groups, activator adjuvants and utility adjuvants. The former directly enhances the efficacy of a herbicide through increasement of herbicide absorption, spreading, cuticular penetration, rainfastness and retention enhancement, and photodegradation of the herbicide can also be decreased. And the latter is utilized for improving application characteristics, behaviors and physical properties of herbicides and reducing or minimizing unwanted side effects on application.展开更多
The paper researched effect of adjuvants on activity and persistence of soil-applied herbicide Anwei.There were five adjuvants (fertility, Q7, oil, anionic and nonionic surfactants) in the experiment. We explored the ...The paper researched effect of adjuvants on activity and persistence of soil-applied herbicide Anwei.There were five adjuvants (fertility, Q7, oil, anionic and nonionic surfactants) in the experiment. We explored the influence of adjuvants on activity and persistence of Anwei by field trial. The results indicated that Q7, oil, anionic surfactant can increased activity of Anwei, and can lengthened its persistence for about five days.展开更多
In order to investigate the physiological injury of barley caused by the low temperature after herbicides, tillering barley seedlings planted in plastic cups were pretreated in illumination incubator at 15℃ and 12 h-...In order to investigate the physiological injury of barley caused by the low temperature after herbicides, tillering barley seedlings planted in plastic cups were pretreated in illumination incubator at 15℃ and 12 h-light per day for 7 days, and then subjected to herbicide treatment, prometryn （with the concentrations of 0, 0.15%, 0.30%, and 0.45%） or isoproturon （with the concentrations of 0, 0.30%, 0.60%, and 0.90%）, and the SOD activity, the CAT activity, the POD activity, the MDA content, proline content, soluble protein content, electrical conductivity, and the rate of O2 were determined and analyzed. The results showed that the low-temperature was the most important, and the treatment-time of low-temperature was another significant influencing factor on the physiological and biochemical indices of barley seedlings. However, all of the physiological and biochemical indices determined were not affected by the kinds of herbicides and herbicide concentrations, and the SOD was stable and should play the more prominent role on extracting of free radicals according to the stepwise regression and correlation. The herbicide concentrations should be increased in the future research for truly reflecting the effects of the herbicide concentration on the physiological and biochemical indices of barley seedlings.展开更多
Background Herbicide tolerance in crops enables them to survive when lethal doses of herbicides are applied to surrounding weeds.Herbicide-tolerant crops can be developed through transgenic approaches or traditional m...Background Herbicide tolerance in crops enables them to survive when lethal doses of herbicides are applied to surrounding weeds.Herbicide-tolerant crops can be developed through transgenic approaches or traditional mutagenesis approaches.At present,no transgenic herbicide tolerant cotton have been commercialized in China due to the genetically-modified organism(GMO)regulation law.We aim to develop a non-transgenic herbicide-tolerant cotton through ethyl methanesulfonate(EMS)mutagenesis,offering an alternative choice for weed management.Results Seeds of an elite cotton cultivar Lumianyan 37(Lu37)were treated with EMS,and a mutant Lu37-1 showed strong tolerance to imidazolinone(IMI)herbicides was identified.A novel nonsynonymous substitution mutation Ser642Asn at acetolactate synthase(ALS)(Gh_D10G1253)in Lu37-1 mutant line was found to be the potential cause to the IMI herbicides tolerance in cotton.The Ser642Asn mutation in ALS did not present among the genomes of natural Gossypium species.Cleaved amplified polymorphic sequence(CAPS)markers were developed to identify the ALS mutant allele.The Arabidopsis overexpressing the mutanted ALS also showed high tolerance to IMI herbicides.Conclusion The nonsynonymous substitution mutation Ser642Asn of the ALS gene Gh_D10G1253 is a novel identi-fied mutation in cotton.This substitution mutation has also been identified in the orthologous ALS genes in other crops.This mutant ALS allele can be used to develop IMI herbicide-tolerant crops via a non-transgenic or transgenic approach.展开更多
Trifloxysulfuron(Envoke)is an acetolactate synthase-inhibitor herbicide and can be used to control many broadleaf weeds and nutsedges in cotton production.However,there is a lack of information on genotypic variation ...Trifloxysulfuron(Envoke)is an acetolactate synthase-inhibitor herbicide and can be used to control many broadleaf weeds and nutsedges in cotton production.However,there is a lack of information on genotypic variation in response to the herbicide.In this field study,60 Pima(Gossypium barbadense L.)lines,122 Upland(G.hirsutum L.)lines,and 9 Upland×Pima segregating populations were divided into five tests(18A,18B,18G,18RB,and 18HQ)to evaluate tri-floxysulfuron tolerance at the 7-true leaf stage(42 days after planting)under the same field conditions in 2018.Across the five tests,Pima cotton genotypes tested in this study did not show any visual crop injury based on percentage of plants with chlorosis at 6 days after treatment(DAT),indicating consistent and high levels of trifloxysulfuron toler-ance.However,the response to trifloxysulfuron within Upland cotton is highly variable.While Upland cotton is overall more sensitive to trifloxysulfuron with crop injury up to 80%than Pima cotton,19 lines had injury below 5%including one line with no visual injury,and 19 lines had injury between 5%and 10%.In test 18HQ with 15 transgenic Upland cultivars and 17 non-transgenic Upland lines,the analysis of variance detected a significant genotypic difference.The broad-sense heritability estimates for trifloxysulfuron tolerance based on crop injury at 6 DAT was 0.555,suggesting that trifloxysulfuron tolerance in Upland cotton is moderately heritable.This study represents the first report that Pima cotton and many Upland cotton lines are highly tolerant to trifloxysulfuron with no or little crop injury.展开更多
The agricultural production on the irrigated grounds can not carry on without mineral fertilizers,pesticides and herbicides.Especially it is shown in Uzbekistan, in cultivation of cotton.There is an increase in minera...The agricultural production on the irrigated grounds can not carry on without mineral fertilizers,pesticides and herbicides.Especially it is shown in Uzbekistan, in cultivation of cotton.There is an increase in mineralization,rigidity,quantity of heavy metals,phenols and other pollutions in the cotton fields.Thus there is an exhaustion of stocks of fresh underground waters.In the year 2003 we were offered to create展开更多
Plastid localized acetyl-CoA carboxylase(ACCase;EC 6.4.1.2)is a target for aryloxyphenoxypropionates(APPs)and cyclohexanediones(CHDs),two groups of selective herbicides used in controlling grassy weeds.Wheat and barle...Plastid localized acetyl-CoA carboxylase(ACCase;EC 6.4.1.2)is a target for aryloxyphenoxypropionates(APPs)and cyclohexanediones(CHDs),two groups of selective herbicides used in controlling grassy weeds.Wheat and barley are important cereal crops in the grass(Poaceae or Gramineae)family,and thus sensitive for those herbicides.Characterization of this form of ACCase(or ACC1)in wheat and barley is essential if these agents are used in the sustainable agriculture.In this study,it was confirmed that a single ACC1 gene presented on the second chromosome per homologous group in common wheat,wild emmer wheat,goat grass and barley.Using CRISPR/Cas9,the barley ACC1 gene was edited,specifically in the carboxyl transferase(CT)domain that was critical for herbicide responses in grass species.Two new alleles were generated,one with a 3-bp deletion leading to ACC1:p.Ile1878del and one with a 26-bp deletion causing ACC1:p.Ser2099_Lys2311del.Both were recovered as heterozygotes in the T0 generation.All the seven T0 plants harboring the 3-bp deletion grew normally,but the only T0 plant with 26-bp deletion died at the extension stage(Zadoks 32),probably because there was inadequate ACC1 activity when the plant was big.In the T1 generation,the 3-bp deletion(or Ile1878del)did not impact the edited plants in tiller numbers,tiller height,spike length and spikelet numbers,when compared to the wild-type allele in the non-edited segregants.This study demonstrated that CRISPR/Cas9 was practical to generate single amino acid deletions in the ACC1 protein and the Ile1878 deletion did not compromise plant growth.Unfortunately,the ACC1:p.Ile1878del protein did not confer resistance to the currently tested APP herbicides,including clethodim,haloxyfop,quizalofop-Pethyl and sethoxydim.展开更多
Background Weed infestation in cotton has been reported to offer severe competition and cause yield reduction to a large extent.Weeding via cultural practices is time consuming,tedious,and expensive due to long durati...Background Weed infestation in cotton has been reported to offer severe competition and cause yield reduction to a large extent.Weeding via cultural practices is time consuming,tedious,and expensive due to long duration of cotton crop and regular monsoon rains during cotton production in India.Chemical weed control has been successfully utilized in cotton in the recent past.However,continuous use of similar herbicides leads to resistance in weeds against herbicides.And when sprayed to the field,herbicides not only suppress weeds but leave undesirable residues in the soil that are hazardous to the environment.Therefore,a study was performed at cotton research area at Chaudhary Charan Singh Haryana Agricultural University,Hisar,Haryana during two consecutive kharif seasons(2020 and 2021)to determine the most suitable and sustainable weed management strategy through the integration of chemical and cultural methods.Results Mulching with rice straw of 7.5 t ha^(-1)resulted in significantly higher cotton seed yield(3189 and 3084 kg ha^(-1))and better weed control in comparison to no mulch treatments(2990 and 2904 kg ha^(-1))in 2020 and 2021,respectively.Among various weed management levels,the significantly lowest cotton seed yield was recorded in untreated control(1841 and 1757 kg·ha^(-1)during 2020 and 2021,respectively)in comparison to other treatments while all other treatments were statistically at par with each other during both years of crop experimentation.Conclusion Mulching with rice straw of 7.5 t·ha^(-1)along with a pre-emergence application of pendimethalin(active ingredient)at 1.5 kg·ha^(-1)fb(followed by)one hoeings at 45 days after sowing(DAS)and fb glyphosate 2 kg·ha^(-1)(Shielded spray)at 90 DAS is a viable option for effective control of grassy and broadleaved weeds in Bt cotton in north-west India.展开更多
文摘Background The intensive use of herbicides in agriculture raises concerns about their residual impacts on non-target crops such as cotton(Gossypium hirsutum L.),which is often rotated with cereals,sugar beet,and canola.Butisanstar(BUT)and clopyralid(CLO)are widely used for broadleaf weed control in these rotations.However,how residual herbicide activity influences cotton growth and development is not well understood.This study evaluated these residual effects by measuring multiple growth parameters in a greenhouse.Cotton was grown for 40 days in soil incubated for 90 days with herbicide treatments arranged in a factorial design(type:BUT,CLO,and their combination;dose:0,1/2,1,2,and 5×recommended field dose[RFD]).Results Herbicide residues reduced cotton growth in a dose-dependent manner,with greater inhibition at higher doses.The combined BUT+CLO treatment produced the strongest negative effects,followed by CLO and then BUT alone.Compared with controls,seedling emergence declined by 12%–83%,root length by 12%–87%,plant height by 10%–84%,and chlorophyll index by 12%–80%across treatments from 1/2×RFD BUT to 5×RFD BUT+CLO.Root and shoot biomass also decreased significantly.Under the 5×RFD combined treatment,shoot N,P,and K concentrations dropped by 48%,78%,and 70%,respectively,relative to the control.Conclusions Even low levels of residual BUT and CLO impair cotton growth.To mitigate these effects,it should avoid planting cotton on recently treated soils,leave sufficient intervals between herbicide application and cotton planting,and apply soil amendments to boost microbial degradation.These measures are essential for sustaining soil health and cotton productivity.
基金Supported by the Funds of the Scientific Research Foundation of Northeast Agricultural University(2010RCB53)
文摘The use of genetically modified organisms （GMOs） as food products becomes more and more widespread. The European Union has implemented a set of very strict procedures for the approval to grow, import and/or utilize GMOs as food or food ingredients. Thus, analytical methods for detection of GMOs are necessary in order to verify compliance with labelling requirements. There are few effective screening methods for processed GM （genetically modified） products. Three anti-herbicide genes （CP4- EPSPS, BAR and PAT） are common exogenous genes used in commercialized transgenic soybean, maize and rice, In the present study, a new SYBR Green qPCR screening method was developed to simultaneously detect the three exogenous anti-herbicide genes and one endogenous gene in a run. We tested seven samples of representative processed products （soya lecithin, soya protein powder, chocolate beverage, infant rice cereal, maize protein powder, maize starch, and maize jam） using the developed method, and amplicons of endogenous gene and transgenic fragments were obtained from all the processed products, and the sensitivity was 0.1%. These results indicated that SYBR Green qPCR screening method was appropriate for qualitative detection of transgenic soybean, maize and rice in processed products.
基金Supported by the National Key Research and Development Program of China(2017YFD0200307)
文摘The resistance and cross-resistance of Scirpus juncoides Roxb.to ALS-inhibiting herbicides were tested to provide theoretical basis for effectively control Scirpus juncoides Roxb.and rational use of herbicides.To identify the resistance and crossresistance of 19 populations from nine areas in Heilongjiang Province to four ALS-inhibiting herbicides by agar method and the whole-plant assay.The results are as the followings,the two bioassay methods had good correlation,the resistance indexes in the same area were different by two means,but resistant level was the same,similarity up to 89.5%.The resistant rates to pyrazosulfuronethyl,bensulfuron-methyl,penoxsulam and pyribenzoxim were 26.3%,36.8%,36.1%and 21.1%,respectively.Shangzhi populations evolved the highest level of resistance to pyrazosulfuron-methyl with a resistance index of 15.56.Shangzhi,Tonghe,Fangzheng and Jixi populations showed cross-resistance to four ALS-inhibiting herbicides,accounting for 26.3%.The resistance of Scirpus juncoides Roxb.to four ALS-inhibiting herbicides in Heilongjiang paddy field was low to moderate,five populations showed cross-resistance to four ALS-inhibiting herbicides.
文摘This study examined the adoption of herbicides by arable farmers in Edo State. It assessed the proportion of arable farmers using herbicides, level of use and factors affecting adoption of herbicides. Simple random sampling was used to compose a sample size of 556 respondents. Various descriptive and inferential statistics were employed in data analyses. The results showed that onehalf of the respondents used herbicides(27.9% regularly using herbicides), and most of the adopters used non-selective herbicide. Avalanche of factors, including education attainment, farm size and farming experience also affected the adoption of herbicides.
文摘The history, present status and future prospects of adjuvants application in herbicides were briefly reviewed. Adjuvants can be separated into two groups, activator adjuvants and utility adjuvants. The former directly enhances the efficacy of a herbicide through increasement of herbicide absorption, spreading, cuticular penetration, rainfastness and retention enhancement, and photodegradation of the herbicide can also be decreased. And the latter is utilized for improving application characteristics, behaviors and physical properties of herbicides and reducing or minimizing unwanted side effects on application.
文摘The paper researched effect of adjuvants on activity and persistence of soil-applied herbicide Anwei.There were five adjuvants (fertility, Q7, oil, anionic and nonionic surfactants) in the experiment. We explored the influence of adjuvants on activity and persistence of Anwei by field trial. The results indicated that Q7, oil, anionic surfactant can increased activity of Anwei, and can lengthened its persistence for about five days.
基金Supported by the National Natural Science Foundation of China (31000712)
文摘In order to investigate the physiological injury of barley caused by the low temperature after herbicides, tillering barley seedlings planted in plastic cups were pretreated in illumination incubator at 15℃ and 12 h-light per day for 7 days, and then subjected to herbicide treatment, prometryn （with the concentrations of 0, 0.15%, 0.30%, and 0.45%） or isoproturon （with the concentrations of 0, 0.30%, 0.60%, and 0.90%）, and the SOD activity, the CAT activity, the POD activity, the MDA content, proline content, soluble protein content, electrical conductivity, and the rate of O2 were determined and analyzed. The results showed that the low-temperature was the most important, and the treatment-time of low-temperature was another significant influencing factor on the physiological and biochemical indices of barley seedlings. However, all of the physiological and biochemical indices determined were not affected by the kinds of herbicides and herbicide concentrations, and the SOD was stable and should play the more prominent role on extracting of free radicals according to the stepwise regression and correlation. The herbicide concentrations should be increased in the future research for truly reflecting the effects of the herbicide concentration on the physiological and biochemical indices of barley seedlings.
基金This research was funded by the National Key Research and Development Program of China,grant number 2016YFD0101418the National Natural Science Foundation of China,grant number 32172047.
文摘Background Herbicide tolerance in crops enables them to survive when lethal doses of herbicides are applied to surrounding weeds.Herbicide-tolerant crops can be developed through transgenic approaches or traditional mutagenesis approaches.At present,no transgenic herbicide tolerant cotton have been commercialized in China due to the genetically-modified organism(GMO)regulation law.We aim to develop a non-transgenic herbicide-tolerant cotton through ethyl methanesulfonate(EMS)mutagenesis,offering an alternative choice for weed management.Results Seeds of an elite cotton cultivar Lumianyan 37(Lu37)were treated with EMS,and a mutant Lu37-1 showed strong tolerance to imidazolinone(IMI)herbicides was identified.A novel nonsynonymous substitution mutation Ser642Asn at acetolactate synthase(ALS)(Gh_D10G1253)in Lu37-1 mutant line was found to be the potential cause to the IMI herbicides tolerance in cotton.The Ser642Asn mutation in ALS did not present among the genomes of natural Gossypium species.Cleaved amplified polymorphic sequence(CAPS)markers were developed to identify the ALS mutant allele.The Arabidopsis overexpressing the mutanted ALS also showed high tolerance to IMI herbicides.Conclusion The nonsynonymous substitution mutation Ser642Asn of the ALS gene Gh_D10G1253 is a novel identi-fied mutation in cotton.This substitution mutation has also been identified in the orthologous ALS genes in other crops.This mutant ALS allele can be used to develop IMI herbicide-tolerant crops via a non-transgenic or transgenic approach.
基金supported in part by Cotton Incorporated and New Mexico Agricultural Experiment Station.
文摘Trifloxysulfuron(Envoke)is an acetolactate synthase-inhibitor herbicide and can be used to control many broadleaf weeds and nutsedges in cotton production.However,there is a lack of information on genotypic variation in response to the herbicide.In this field study,60 Pima(Gossypium barbadense L.)lines,122 Upland(G.hirsutum L.)lines,and 9 Upland×Pima segregating populations were divided into five tests(18A,18B,18G,18RB,and 18HQ)to evaluate tri-floxysulfuron tolerance at the 7-true leaf stage(42 days after planting)under the same field conditions in 2018.Across the five tests,Pima cotton genotypes tested in this study did not show any visual crop injury based on percentage of plants with chlorosis at 6 days after treatment(DAT),indicating consistent and high levels of trifloxysulfuron toler-ance.However,the response to trifloxysulfuron within Upland cotton is highly variable.While Upland cotton is overall more sensitive to trifloxysulfuron with crop injury up to 80%than Pima cotton,19 lines had injury below 5%including one line with no visual injury,and 19 lines had injury between 5%and 10%.In test 18HQ with 15 transgenic Upland cultivars and 17 non-transgenic Upland lines,the analysis of variance detected a significant genotypic difference.The broad-sense heritability estimates for trifloxysulfuron tolerance based on crop injury at 6 DAT was 0.555,suggesting that trifloxysulfuron tolerance in Upland cotton is moderately heritable.This study represents the first report that Pima cotton and many Upland cotton lines are highly tolerant to trifloxysulfuron with no or little crop injury.
文摘The agricultural production on the irrigated grounds can not carry on without mineral fertilizers,pesticides and herbicides.Especially it is shown in Uzbekistan, in cultivation of cotton.There is an increase in mineralization,rigidity,quantity of heavy metals,phenols and other pollutions in the cotton fields.Thus there is an exhaustion of stocks of fresh underground waters.In the year 2003 we were offered to create
基金Supported by China Research and Development Initiative on Genetically Modified Plants(2016ZX08009003-001-006)Hatch Project IDA01587 from the USDA National Institute of Food and Agriculture。
文摘Plastid localized acetyl-CoA carboxylase(ACCase;EC 6.4.1.2)is a target for aryloxyphenoxypropionates(APPs)and cyclohexanediones(CHDs),two groups of selective herbicides used in controlling grassy weeds.Wheat and barley are important cereal crops in the grass(Poaceae or Gramineae)family,and thus sensitive for those herbicides.Characterization of this form of ACCase(or ACC1)in wheat and barley is essential if these agents are used in the sustainable agriculture.In this study,it was confirmed that a single ACC1 gene presented on the second chromosome per homologous group in common wheat,wild emmer wheat,goat grass and barley.Using CRISPR/Cas9,the barley ACC1 gene was edited,specifically in the carboxyl transferase(CT)domain that was critical for herbicide responses in grass species.Two new alleles were generated,one with a 3-bp deletion leading to ACC1:p.Ile1878del and one with a 26-bp deletion causing ACC1:p.Ser2099_Lys2311del.Both were recovered as heterozygotes in the T0 generation.All the seven T0 plants harboring the 3-bp deletion grew normally,but the only T0 plant with 26-bp deletion died at the extension stage(Zadoks 32),probably because there was inadequate ACC1 activity when the plant was big.In the T1 generation,the 3-bp deletion(or Ile1878del)did not impact the edited plants in tiller numbers,tiller height,spike length and spikelet numbers,when compared to the wild-type allele in the non-edited segregants.This study demonstrated that CRISPR/Cas9 was practical to generate single amino acid deletions in the ACC1 protein and the Ile1878 deletion did not compromise plant growth.Unfortunately,the ACC1:p.Ile1878del protein did not confer resistance to the currently tested APP herbicides,including clethodim,haloxyfop,quizalofop-Pethyl and sethoxydim.
文摘Background Weed infestation in cotton has been reported to offer severe competition and cause yield reduction to a large extent.Weeding via cultural practices is time consuming,tedious,and expensive due to long duration of cotton crop and regular monsoon rains during cotton production in India.Chemical weed control has been successfully utilized in cotton in the recent past.However,continuous use of similar herbicides leads to resistance in weeds against herbicides.And when sprayed to the field,herbicides not only suppress weeds but leave undesirable residues in the soil that are hazardous to the environment.Therefore,a study was performed at cotton research area at Chaudhary Charan Singh Haryana Agricultural University,Hisar,Haryana during two consecutive kharif seasons(2020 and 2021)to determine the most suitable and sustainable weed management strategy through the integration of chemical and cultural methods.Results Mulching with rice straw of 7.5 t ha^(-1)resulted in significantly higher cotton seed yield(3189 and 3084 kg ha^(-1))and better weed control in comparison to no mulch treatments(2990 and 2904 kg ha^(-1))in 2020 and 2021,respectively.Among various weed management levels,the significantly lowest cotton seed yield was recorded in untreated control(1841 and 1757 kg·ha^(-1)during 2020 and 2021,respectively)in comparison to other treatments while all other treatments were statistically at par with each other during both years of crop experimentation.Conclusion Mulching with rice straw of 7.5 t·ha^(-1)along with a pre-emergence application of pendimethalin(active ingredient)at 1.5 kg·ha^(-1)fb(followed by)one hoeings at 45 days after sowing(DAS)and fb glyphosate 2 kg·ha^(-1)(Shielded spray)at 90 DAS is a viable option for effective control of grassy and broadleaved weeds in Bt cotton in north-west India.
