| Zinc(Zn)deficiency in human body and plant is a very serious problem.With the progress of science and technology,traditional food crops cannot satisfy the need of Zn from foods.Scientists begin to explore the zinc-rich high quality of nutritional foods.Rice is a staple crop that feeds more than half of the population all over the world.Thus,increasing the concentration of zinc in rice crops is crucial to improve the human healthCurrently,zinc sulfate is the most common fertilizer practically used in crop production.The purpose of this experiment is to explore the best use of zinc sulfate fertilizer and to improve the content of zinc in rice in a safe way.In this study,we performed both pot and field experiments to test the desirable concentration of zinc-rich foliar tissues and found out the best spraying period and concentration as well.By the systematic study,we determined the effect of the zinc-rich fertilizer on rice growth,physiological and grain quality.We also assessed a set of ZIP family metal transporters.Detail results are described as follows:(1)Spraying foliar zinc fertilizer significantly promoted the rice growth at the grain filling stage.The best spraying concentration of zinc was 0.1%.With the supplemental supply of zinc,the flag leaf chlorophyll content increased by 15%,the soluble protein increased by 24%,and the vitamin Content increased by 28%.(2)Spraying 0.1%foliar zinc fertilizer slightly increased the gel consistency and total starch content of rice grain,and reduced gelatinization temperature.(3)At the foliage,spraying zinc fertilizer(0.1%)effectively enhanced the zinc content of rice plants by 7%,as compared to the control.(4)The transcriptional levels of OsZIP2,OsZIP6,OsZIP8 and OsZIP10 were significantly decreased after 0.1-02%zinc spraying treatment and 0.2%treatment compared to the control group.The expression level of OsZIP4 with 0.1%zinc spraying was significantly higher than that of the control group.Compared with the control group,the expression level of OsZIP5 and OsZIP9 with 0.2%was significantly higher.The expression levels of OsZIP3,OsZIP4 and OsZIP5 were significantly up-regulated in rice with 0.1%Zn treatment,but the expression level of OsZIP3,OsZIP4 and OsZIP5 was significantly reduced.While the expression level of OsZIP2 was down-regulated by 0.1%zinc fertilizer,the expression level of OsZIP2 was up-regulated after 0.2%Zn treatment.The expression of OsZIP6,OsZIP7 and OsZIP9 was not significantly changed in 0.1%Zn treatment compared to the control group,but was significantly up-regulated by 0.2%Zn treatment. |
