| Soybean is one of the main food crops in China.However,because of the high cost,low yield and poor quality,the market competitiveness of domestic soybean is weak.A large number of imported soybeans are needed to meet domestic demand every year.Therefore,improving soybean yield and quality will be the only way to revitalize soybean industry.As an exogenous regulator,rare earth elements hve been widely used in grain,vegetable,forestry and animal husbandry,and have brought considerable economic benefits.At the same time,the biological effects of applying the suitable concentration of rare earth solutions to improve the quality,increase the yield and enhance the resistance of the crops were also clarified.But in recent years,few studies have been made about the mechanism of improving crop quality by rare earthelements,which make the development of rare earth agricultural technology slowly.In this pot experiment,soybean Dongnong42?high-protein?,Dongnong47?high-fat?and Dongnong52?intermediate?of different genotypes in northeast China were used as experimental materials.Spraying different concentrations of LaCl3 solution(100,150,200 mg·L-1),CeCl3 solution(30,60,90 mg·L-1)and LaCl3+CeCl3 solution(40,60,70 mg·L-1)in seedling stage and flowering stage to study the effect of rare earth with different varieties and concentrations on the on physiological indexes of soybean leaves and the yield and quality of soybean after maturity.In addition,in order to reveal the molecular mechanism of controlling the quality of soybean seeds by rare earth,a TMT-based proteomic approach was used to investigate the proteomes of Dongnong42 soybean seeds under 30mg·L-1 CeCl3 and 100 mg·L-1 LaCl3 treatments.The results showed that:?1?The content of soluble sugar in soybean leaves as well as the activity of nitrate reductase and glutamine synthetase in soybean leaves can be significantly increased by spraying the suitable concentration of rare earth solution on the leaf surface.For Dongnong42,the content of soluble sugar in leaves was highest under the treatment of 70 mg·L-1 LaCl3+CeCl3,and increased by 14.75%?P>0.05?compared with CK.The activity of nitrate reductase and glutamine synthetase in leaves were highest under the treatment of 30 mg·L-1 CeCl3,which was significantly higher than that of CK by 26.10%and23.54%,respectively.For Dongnong47,the content of soluble sugar in leaves was highest under the treatment of 90 mg·L-1 CeCl3,and significantly increased by 38.77%compared with CK.The activity of nitrate reductase and glutamine synthetase in leaves were highest under the treatment of 30 mg·L-1CeCl3,which was significantly higher than that of CK by 36.57%and 29.03%,respectively.For Dongnong52,the content of soluble sugar in leaves was highest under the treatment of 60 mg·L-1 CeCl3,and significantly increased by 39.04%compared with CK.The activity of nitrate reductase in leaves was highest under the treatment of 90 mg·L-1 CeCl3,and significantly increased by 23.33%compared with CK.The activity of glutamine synthetase in leaves was highest under the treatment of 100 mg·L-1LaCl3,and significantly increased by 28.97%compared with CK.?2?The content of protein in soybean seed was increased by spraying the suitable concentration of rare earth solution on the leaf surface,but the content of fat was also reduced.The protein content of Dongnong42 and Dongnong47 were the highest under the treatment of 30 mg·L-1 CeCl3,which were significantly higher than that of CK by 5.61%and 5.03%,respectively.The protein content of Dongnong52 was the highest under the treatment of 60 mg·L-1 LaCl3+CeCl3,and significantly increased by 5.19%compared with CK.There was no significant increase in fat content after spraying rare earth solution.On the contrary,the fat content of Dongnong42 under the treatments of 30 mg·L-1 CeCl3 and 60mg·L-1 CeCl3 and Dongnong47 under the treatment of 70 mg·L-1 LaCl3+CeCl3 lower than that in the CK by 5.10%,4.17%,2.93%,respectively.After rare earth treatment,the total contents of protein and fat in the seeds of three different soybean varieties were higher than those of CK.?3?The results showed that suitable concentrations of LaCl3,CeCl3 or LaCl3+CeCl3 solutions could decrease the content of 7S protein,and could increase the content of 11S protein.The 7S protein content of Dongnong42 was the lowest under the treatment of 60 mg·L-1 CeCl3,which was significantly decreased by 6.46%compared with CK,and the 11s protein content and 11S/7S were the highest in all treatments,which were significantly higher than CK by 3.40%,10.26%,respectively.There was no significant effect on the content of 7S protein in Dongnong47 and Dongnong52 by spraying rare earth solution.The 11S protein content and 11S/7S of Dongnong47 were the highest under the treatment of 30 mg·L-1 CeCl3,which were significantly higher than that of CK by 5.61%and 5.03%,respectively.The 11S protein content and 11S/7S of Dongnong52 were the highest under the treatment of 30 mg·L-1 CeCl3,which were significantly higher than that of CK by 3.58%and 7.69%,respectively.?4?The suitable concentration of rare earth solution significantly increased the yield of soybean at mature stage,but it reduced the yield of soybean under the treatment of high concentration of rare earth solution.The yeild of Dongnong42 was the highest under the 70 mg·L-1 LaCl3+CeCl3 treatment,which was significantly increased by 23.73%than that of CK.The yeild of Dongnong47 was the highest under the 60 mg·L-1 LaCl3+CeCl3 treatment,which was significantly increased by 10.60%than that of CK.The yeild of Dongnong52 was the highest under the 60 mg·L-1 CeCl3 treatment,which was significantly increased by 10.60%than that of CK.Under 90 mg·L-1 CeCl3 treatment,the yield of Dongnong52decreased significantly,which was 31.62%lower than that of CK.?5?To be identified as being significantly differentially expressed,a protein should be quantified with at least three peptides in each experimental replicate,a p-value smaller than 0.05 and fold change greater than 1.2 or less than 0.8.Based on these criteria,97 DEPs were identified in soybean seeds,of which 63 displayed increases,and 34 displayed decreases in abundance under the treatment of 30mg·L-1 CeCl3.And 108 DEPs were identified in soybean seeds,of which 57 showed an increase,and 51showed a decrease in abundance after 100 mg·L-1 LaCl3 treatment.The differential proteins were annotated by Gene Ontology,which were the most abundant in the three categories of cell proliferation,catalytic activity and metabolic process.KEGG pathway analysis showed that differential proteins were mainly involved in protein processing in endoplasmic reticulum,ribosome,glycometabolism and starch synthesis.All these identified DEPs in seeds can be divided into the following categories:protein synthesis,protein modification,stress response,glucose metabolism,cell structure,cell maturation and aging,and other proteins.This indicated that spraying rare earth solution promoted the synthesis of protein at the maturity of soybean,glucose metabolism and sucrose transport were accelerated,which was beneficial to the accumulation of storage protein and starch and the formation of yield. |
PDF Full Text Request