Leaves are the main photosynthesis organ that directly determines crop yield and biomass.Dissecting the regulatory mechanism of leaf development is crucial for food security and ecosystem turn-over.Here,we identified ...Leaves are the main photosynthesis organ that directly determines crop yield and biomass.Dissecting the regulatory mechanism of leaf development is crucial for food security and ecosystem turn-over.Here,we identified the novel function of R2R3-MYB transcription factors CsRAXs in regulating cucumber leaf size and fruiting ability.Csrax5 single mutant exhibited enlarged leaf size and stem diameter,and Csrax1/2/5 triple mutant displayed further enlargement phenotype.Overexpression of CsRAX1 or CsRAX5 gave rise to smaller leaf and thinner stem.The fruiting ability of Csrax1/2/5 plants was significantly enhanced,while that of CsRAX5 overexpression lines was greatly weakened.Similarly,cell number and free auxin level were elevated in mutant plants while decreased in overexpression lines.Biochemical data indicated that CsRAX1/5 directly promoted the expression of auxin glucosyltransferase gene CsUGT74E2.Therefore,our data suggested that CsRAXs function as repressors for leaf size development by promoting auxin glycosylation to decrease free auxin level and cell division in cucumber.Our findings provide new gene targets for cucumber breeding with increased leaf size and crop yield.展开更多
Lodging is a major yield-limiting factor of quinoa production.In 2018 and 2019,the orthogonal field experiments were conducted to investigate the responses of quinoa lodging risk and yield to irrigation threshold(soil...Lodging is a major yield-limiting factor of quinoa production.In 2018 and 2019,the orthogonal field experiments were conducted to investigate the responses of quinoa lodging risk and yield to irrigation threshold(soil matric potential of−15,−25 and−55 kPa),nitrogen rate(80,160 and 240 kg·ha^(−1))and planting density(20,30 and 40 plants m^(−2)).Results showed that high irrigation thresholds and nitrogen rates significantly(P<0.05)increased plant height and fresh weight per plant,and high planting densities reduced stem diameter and strength,all of those led to significantly(P<0.05)high lodging risks.The−15 and−55 kPa treatments gave the lowest actual yield(P<0.05)in 2018 and 2019,respectively.Higher lodging rate with a nitrogen rate of 240 kg·ha^(−1) resulted in a lower actual yield than 80 and 160 kg·ha^(−1) in both years.Planting density of 30 plants m^(−2) gave a significantly(P<0.05)greater estimated yield than 20 plants m^(−2) and had a lower lodging rate than 40 plants m^(−2),resulting in the maximum actual yield among planting densities.In conclusion,a moderate irrigation threshold of−25 kPa,a nitrogen rate of 80−160 kg·ha^(−1) and an intermediate planting density of 30 plants m−2 were determined to be best for quinoa cultivation in North-western China.In addition,the lower-stem lodging index(quarter plant height)could evaluate lodging risk more accurately than middle-stem(half plant height)or upper-stem(three quarters plant height)lodging indexes.展开更多
基金supported by grants from the National Natural Science Foundation of China[32025033,31930097 and 32372699]Pinduoduo-China Agricultural University Research Fund[PC2023B01002].
文摘Leaves are the main photosynthesis organ that directly determines crop yield and biomass.Dissecting the regulatory mechanism of leaf development is crucial for food security and ecosystem turn-over.Here,we identified the novel function of R2R3-MYB transcription factors CsRAXs in regulating cucumber leaf size and fruiting ability.Csrax5 single mutant exhibited enlarged leaf size and stem diameter,and Csrax1/2/5 triple mutant displayed further enlargement phenotype.Overexpression of CsRAX1 or CsRAX5 gave rise to smaller leaf and thinner stem.The fruiting ability of Csrax1/2/5 plants was significantly enhanced,while that of CsRAX5 overexpression lines was greatly weakened.Similarly,cell number and free auxin level were elevated in mutant plants while decreased in overexpression lines.Biochemical data indicated that CsRAX1/5 directly promoted the expression of auxin glucosyltransferase gene CsUGT74E2.Therefore,our data suggested that CsRAXs function as repressors for leaf size development by promoting auxin glycosylation to decrease free auxin level and cell division in cucumber.Our findings provide new gene targets for cucumber breeding with increased leaf size and crop yield.
基金supported by the Ministry of Water Resources(201501017)the Foundation for Innovative Research Groups of the National Natural Science Foundation(51621061)the Major Program of the National Natural Science Foundation(51439006)of China.
文摘Lodging is a major yield-limiting factor of quinoa production.In 2018 and 2019,the orthogonal field experiments were conducted to investigate the responses of quinoa lodging risk and yield to irrigation threshold(soil matric potential of−15,−25 and−55 kPa),nitrogen rate(80,160 and 240 kg·ha^(−1))and planting density(20,30 and 40 plants m^(−2)).Results showed that high irrigation thresholds and nitrogen rates significantly(P<0.05)increased plant height and fresh weight per plant,and high planting densities reduced stem diameter and strength,all of those led to significantly(P<0.05)high lodging risks.The−15 and−55 kPa treatments gave the lowest actual yield(P<0.05)in 2018 and 2019,respectively.Higher lodging rate with a nitrogen rate of 240 kg·ha^(−1) resulted in a lower actual yield than 80 and 160 kg·ha^(−1) in both years.Planting density of 30 plants m^(−2) gave a significantly(P<0.05)greater estimated yield than 20 plants m^(−2) and had a lower lodging rate than 40 plants m^(−2),resulting in the maximum actual yield among planting densities.In conclusion,a moderate irrigation threshold of−25 kPa,a nitrogen rate of 80−160 kg·ha^(−1) and an intermediate planting density of 30 plants m−2 were determined to be best for quinoa cultivation in North-western China.In addition,the lower-stem lodging index(quarter plant height)could evaluate lodging risk more accurately than middle-stem(half plant height)or upper-stem(three quarters plant height)lodging indexes.
