Conservation tillage may improve yield of cotton in addition to improvement in soil quality if practiced for longer period. However, the practice may not be productive in short-term particularly when severe weeds are ...Conservation tillage may improve yield of cotton in addition to improvement in soil quality if practiced for longer period. However, the practice may not be productive in short-term particularly when severe weeds are infesting the crops such as Cynodon dactylon, Conyza canadensis, Tribulus terrestris, and Cyperus rotundus, etc. Recent studies indicate that conventional tillage （CT） is more productive than zero tillage （ZT）/reduced tillage （RT）. Performance of cotton under three tillage systems, viz., ZT, RT and CT; and five herbicides, i.e., haloxyfop-R-methyl 10.8 EC （108 g a.i. ha^-1）, lactofen 24 EC （168 g a.i. ha^-1）, haloxyfop 10.8 EC ＋ lactofen 24 EC, hand weeding, and weedy check were evaluated during 2010-2011 at Gomal University, D.I.Khan, Pakistan, to explore the best management option for effective weed control, enhanced yield and quality of cotton grown after wheat. The results revealed that hand weeding and Haloxyfop as post emergence alone or in combination with Lactofen reduced weed density to the minimum irrespective of the tillage systems. Excessive rainfall and cooler temperature limited cotton growth and yield in 2010. The adverse weather conditions had more adverse effect on boll weight under ZT and RT than CT. Haloxyfop ＋ lactofen produced higher seed cotton yield in RT than ZT, however, it could not exceed CT. Broad-spectrum herbicides x CT produced the highest number of bolls/plant, boll weight and seed cotton yield. Fiber quality and net returns were also the highest in broad-spectrum herbicides x CT. In conclusion, broad-spectrum herbicides under CT were more productive in wheat based cropping system on silty clay soil of D.I.Khan.展开更多
EPSPS is a key gene in the shikimic acid synthesis pathway that has been widely used in breeding crops with herbicide resistance.However,its role in regulating cell elongation is poorly understood.Through the overexpr...EPSPS is a key gene in the shikimic acid synthesis pathway that has been widely used in breeding crops with herbicide resistance.However,its role in regulating cell elongation is poorly understood.Through the overexpression of EPSPS genes,we generated lines resistant to glyphosate that exhibit an unexpected dwarf phenotype.A representative line,DHR1,exhibits a stable dwarf phenotype throughout its entire growth period.Except for plant height,the other agronomic traits of DHR1 are similar to its transgenic explants ZM24.Paraffin section observations showed that DHR1 internodes are shortened due to reduced elongation and division of the internode cells.Exogenous hormones confirmed that DHR1 is not a classical brassinolide(BR)-or gibberellin(GA)-related dwarfing mutant.Hybridization analysis and fine mapping confirmed that the EPSPS gene is the causal gene for dwarfism,and the phenotype can be inherited in different genotypes.Transcriptome and metabolome analyses showed that genes associated with the phenylpropanoid synthesis pathway are enriched in DHR1 compared with ZM24.Flavonoid metabolites are enriched in DHR1,whereas lignin metabolites are reduced.The enhancement of flavonoids likely results in differential expression of auxin signal pathway genes and alters the auxin response,subsequently affecting cell elongation.This study provides a new strategy for generating dwarfs and will accelerate advancements in light simplification in the cultivation and mechanized harvesting of cotton.展开更多
分子特征和遗传稳定性是我国转基因植物安全评价流程所需考察的重要数据。利用基因组测序技术对抗除草剂棉花GV-2的T-DNA插入位点、拷贝数及侧翼序列进行解析,并采用实时荧光定量PCR(quantitative real time polymerase chain reaction,...分子特征和遗传稳定性是我国转基因植物安全评价流程所需考察的重要数据。利用基因组测序技术对抗除草剂棉花GV-2的T-DNA插入位点、拷贝数及侧翼序列进行解析,并采用实时荧光定量PCR(quantitative real time polymerase chain reaction,qRT-PCR)、Southern杂交、胶体金试纸及ELISA(enzyme linked immunosorbent assay)方法对连续3代(T3~T5)GV-2转化体中目的基因的表达的稳定性进行验证。结果表明,转化体GV-2中T-DNA以单拷贝形式插入到陆地棉A06染色体2 092 124~2 092 194 bp之间,造成棉花基因组中70 bp DNA的缺失。转化体特异性PCR及Sanger测序结果进一步验证了插入位点的正确性。此外,目的基因及其表达蛋白在不同世代转化体中均可稳定遗传,为转基因棉花GV-2转化体的安全评价提供了有效的支撑。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
文摘Conservation tillage may improve yield of cotton in addition to improvement in soil quality if practiced for longer period. However, the practice may not be productive in short-term particularly when severe weeds are infesting the crops such as Cynodon dactylon, Conyza canadensis, Tribulus terrestris, and Cyperus rotundus, etc. Recent studies indicate that conventional tillage （CT） is more productive than zero tillage （ZT）/reduced tillage （RT）. Performance of cotton under three tillage systems, viz., ZT, RT and CT; and five herbicides, i.e., haloxyfop-R-methyl 10.8 EC （108 g a.i. ha^-1）, lactofen 24 EC （168 g a.i. ha^-1）, haloxyfop 10.8 EC ＋ lactofen 24 EC, hand weeding, and weedy check were evaluated during 2010-2011 at Gomal University, D.I.Khan, Pakistan, to explore the best management option for effective weed control, enhanced yield and quality of cotton grown after wheat. The results revealed that hand weeding and Haloxyfop as post emergence alone or in combination with Lactofen reduced weed density to the minimum irrespective of the tillage systems. Excessive rainfall and cooler temperature limited cotton growth and yield in 2010. The adverse weather conditions had more adverse effect on boll weight under ZT and RT than CT. Haloxyfop ＋ lactofen produced higher seed cotton yield in RT than ZT, however, it could not exceed CT. Broad-spectrum herbicides x CT produced the highest number of bolls/plant, boll weight and seed cotton yield. Fiber quality and net returns were also the highest in broad-spectrum herbicides x CT. In conclusion, broad-spectrum herbicides under CT were more productive in wheat based cropping system on silty clay soil of D.I.Khan.
基金supported by funding from the Natural Science Foundation of Henan Province,China(232300421010)the Key Research and Development Project of Henan Province,China(231111110400)+4 种基金the Hainan Provincial Joint Project of Sanya Yazhou Bay Science and Technology City,China(320LH045)the Hainan Yazhou Bay Seed Laboratory,China(B21HJ0215)the Fundamental Research Funds of State Key Laboratory of Cotton Biology,China(2021CBE03)the Central Public-interest Scientific Institution Basal Research Fund,China(Y2023XK16)the Innovation Program of the Chinese Academy of Agricultural Sciences(CAAS-ASTIPIVFCAAS to F.G.L)。
文摘EPSPS is a key gene in the shikimic acid synthesis pathway that has been widely used in breeding crops with herbicide resistance.However,its role in regulating cell elongation is poorly understood.Through the overexpression of EPSPS genes,we generated lines resistant to glyphosate that exhibit an unexpected dwarf phenotype.A representative line,DHR1,exhibits a stable dwarf phenotype throughout its entire growth period.Except for plant height,the other agronomic traits of DHR1 are similar to its transgenic explants ZM24.Paraffin section observations showed that DHR1 internodes are shortened due to reduced elongation and division of the internode cells.Exogenous hormones confirmed that DHR1 is not a classical brassinolide(BR)-or gibberellin(GA)-related dwarfing mutant.Hybridization analysis and fine mapping confirmed that the EPSPS gene is the causal gene for dwarfism,and the phenotype can be inherited in different genotypes.Transcriptome and metabolome analyses showed that genes associated with the phenylpropanoid synthesis pathway are enriched in DHR1 compared with ZM24.Flavonoid metabolites are enriched in DHR1,whereas lignin metabolites are reduced.The enhancement of flavonoids likely results in differential expression of auxin signal pathway genes and alters the auxin response,subsequently affecting cell elongation.This study provides a new strategy for generating dwarfs and will accelerate advancements in light simplification in the cultivation and mechanized harvesting of cotton.
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.
