At the beginning of silking, maize production began to form, but leaves started senescence and photosynthetic capacity decreased at this time, all of those severely restricted the formation of the production. In order...At the beginning of silking, maize production began to form, but leaves started senescence and photosynthetic capacity decreased at this time, all of those severely restricted the formation of the production. In order to study the effects of exogenous substances on the process of leaf senescence, 40 mg. L-1 DCPTA and 20 mg. L-1 CCC were mixed in the research. When the maize grew to the six expanded leaves stage, 10 mL compound mixtures （TR） were sprayed on both sides of leaves for per plant, and the control was treated with water （CK）. Three plants were selected randomly for determination of physiological index at 10, 20, 30, 40 and 50 days after silking. The results showed that TR could increase the chlorophyll content significantly, FvFm, Fv/F0 and Y（Ⅱ） values of TR were higher than those of CK while F0 values were opposite. Compared with CK, TR increased SOD and POD activities and soluble protein content, and reduced MDA content. Correlation analysis showed that chlorophyll content had negative correlation with F0, and MDA content had negative correlation with other indexes. Compared with CK, TR reduced the negative correlation effect between chlorophyll content and MDA, increased the positive correlation effect between chlorophyll content and Fv/Fm, SOD, PODI and soluble protein. The study provided theoretical and experimental evidence for the application of the compound mixtures of DCPTA and CCC to the production.展开更多
Background:The photosynthetic parameters of cotton plants may be modified by the timing of film removal during their growing period.This study was undertaken during 2015-2017 in Xinjiang,China,to determine to what ext...Background:The photosynthetic parameters of cotton plants may be modified by the timing of film removal during their growing period.This study was undertaken during 2015-2017 in Xinjiang,China,to determine to what extent the film mulching removal time,1 and 10 days before the first irrigation and 1 day before the second irrigation after seedling emergence,influenced cotton's photosynthetic characteristics.The control group(CK)was film-mulched throughout the growth stages.Results:The results suggested the following:(1)Removing mulching-film within 50 days since seedling emergence had adverse effects on soil temperature and moisture.(2)Film-removal before the first or second irrigation after emergence improved the net photosynthetic rate in cotton's later flowering stage and its transpiration rate in mid and later flowed ng stages while enhancing the actual electron transport rate(ETR)and maximum electron transfer rate(ETRmax)between cotton photosystems I and II.(3)Film-removal treatment also increased cotton plants'toleranee to high irradiation after emergence,the trend was more pronounced in the early flowering stage in wetter years.(4)Leaf area index(LAI)of cotton was reduced in the film-removal treatment for which the least accumulation of dry matter occurred in a drought year(i.e.,2015).(5)Film removal caused a yield decrease in the dry year(2015),and the earlier the film was removed,the more seriously the yield decreased.Removing mulching film before the second irrigation could increase the yield of XLZ42 in the rainy year(2016)and the normal rainfall year(2017).Early film removal can in crease the yield of XLZ45 in the rainy year(2016).Conclusions:Collectively,our stud/s experimental results indicate that applying mulch film removal at an appropriate,targeted time after seedling emerge nee had no adverse effects on soil moisture and temperature,and improved the photosy nthetic performance of cotton,thus in creased cotton yield and fiber quality,but no significant difference was reached.展开更多
基金Supported by the National Natural Science Foundation of Youth Science Foundation(31201164)Northeast Agricultural University Doctor Started Foundation(2012RCB01)+1 种基金China Postdoctoral Foundation(2012M511434)Project of National Non-profi t Institute Fund(BSRF201405)
文摘At the beginning of silking, maize production began to form, but leaves started senescence and photosynthetic capacity decreased at this time, all of those severely restricted the formation of the production. In order to study the effects of exogenous substances on the process of leaf senescence, 40 mg. L-1 DCPTA and 20 mg. L-1 CCC were mixed in the research. When the maize grew to the six expanded leaves stage, 10 mL compound mixtures （TR） were sprayed on both sides of leaves for per plant, and the control was treated with water （CK）. Three plants were selected randomly for determination of physiological index at 10, 20, 30, 40 and 50 days after silking. The results showed that TR could increase the chlorophyll content significantly, FvFm, Fv/F0 and Y（Ⅱ） values of TR were higher than those of CK while F0 values were opposite. Compared with CK, TR increased SOD and POD activities and soluble protein content, and reduced MDA content. Correlation analysis showed that chlorophyll content had negative correlation with F0, and MDA content had negative correlation with other indexes. Compared with CK, TR reduced the negative correlation effect between chlorophyll content and MDA, increased the positive correlation effect between chlorophyll content and Fv/Fm, SOD, PODI and soluble protein. The study provided theoretical and experimental evidence for the application of the compound mixtures of DCPTA and CCC to the production.
基金the special fund for scientific research into non-profit industries(agriculture,grant no.201503120).
文摘Background:The photosynthetic parameters of cotton plants may be modified by the timing of film removal during their growing period.This study was undertaken during 2015-2017 in Xinjiang,China,to determine to what extent the film mulching removal time,1 and 10 days before the first irrigation and 1 day before the second irrigation after seedling emergence,influenced cotton's photosynthetic characteristics.The control group(CK)was film-mulched throughout the growth stages.Results:The results suggested the following:(1)Removing mulching-film within 50 days since seedling emergence had adverse effects on soil temperature and moisture.(2)Film-removal before the first or second irrigation after emergence improved the net photosynthetic rate in cotton's later flowering stage and its transpiration rate in mid and later flowed ng stages while enhancing the actual electron transport rate(ETR)and maximum electron transfer rate(ETRmax)between cotton photosystems I and II.(3)Film-removal treatment also increased cotton plants'toleranee to high irradiation after emergence,the trend was more pronounced in the early flowering stage in wetter years.(4)Leaf area index(LAI)of cotton was reduced in the film-removal treatment for which the least accumulation of dry matter occurred in a drought year(i.e.,2015).(5)Film removal caused a yield decrease in the dry year(2015),and the earlier the film was removed,the more seriously the yield decreased.Removing mulching film before the second irrigation could increase the yield of XLZ42 in the rainy year(2016)and the normal rainfall year(2017).Early film removal can in crease the yield of XLZ45 in the rainy year(2016).Conclusions:Collectively,our stud/s experimental results indicate that applying mulch film removal at an appropriate,targeted time after seedling emerge nee had no adverse effects on soil moisture and temperature,and improved the photosy nthetic performance of cotton,thus in creased cotton yield and fiber quality,but no significant difference was reached.
