Effect Of Trace Element On Growth And Development And Mineral Nutrients Absorption Of High-yielding Summer Maize (Zea Mays L.)

Under the conditions of a large amount of N,P and K fertilizers applied in maize production,the effect of trace elements on growth and yield has been paid more and more attention.In this paper,two major hybrid culticar of maize,Xianyu 335 and MC812,were used as materials to observe the effect of trace element Zn,Mn,B on growth,photosynthetic characteristics,grain filling characteristics,floret development and dry matter accumulation of summer maize plants.Such observation could provide theoretical basis and technical support for the application of micronutrients in high-yield summer corn production.The Results showed that:1.Trace elements zinc,manganese and boron had important effects on the growth and development of summer maize plants.The trace elments enlarged the stem diameter and shorten the length of the internode at the base of plant,which shortened plant height,ear height and the center of gravity to some extent.Zinc,manganese and boron promoted the root development of the plant and root numbers significantly increased.Root bleeding fluid increment by zinc,manganese and boron was 5.99%~50.43%,6.56%~29.67% and5.11%~45.27% respectively.2.Trace elements improved the photosynthetic characteristics of summer maize plants.The leaf area index and the chlorophyll content of ear-leavf were effectively enhanced.The senescence rate of leaves after silking was slowed down and the senescence time was also delayed.The leaf senescence rates decreased by zinc,manganese and boron were14.11%~65.74%,21.18%~48.84% and 9.95%~49.41%,respectively.3.Trace elements significantly increased the accumulation of biomass in maize plant and altered the partitioning of assimilation products among different organs.More photosynthetic products was partitioned into leaves and stems before silking and the more was are translocated to the ear and grains after silking.4.Trace elements significantly increased the grain filling rate and the increased rate by zinc,manganese and boron was15.46%~26.14%,10.23%~18.92% and 6.27%~12.62%respectively.The grain dehydration rate during the late time of maturity was also increased by 22.28%~34.10%,10.48%~23.33% and 4.50%~13.42% with the treatment of zinc,manganese and boron respectively,which was beneficial to reduce the water content of grain during harvest.5.Trace elements significant affected mineral nutrient absorption in different organs of summer maize plant.Accumulation of both macronutrients(nitrogen,phosphorus andpotassium)and micrionutrients(zinc,manganese and boron)in maize plant and grain were significantly increased.The accumulation amount of N increased by 31.91%~45.54%,22.09%~32.75% and 14.95%~20.05% with treantment of zinc,manganese and boron respectively,P 48.90%~63.75%,28.19%~43.62% and 5.61%~12.80% respectively,and K95.73%~141.43%,78.29%~85.43% and 52.49%~60.11% respectively.6.Trace elements had significant effects on yield components and grain yiled.Number of silking flowers increased with the number of unfertilized flowers and abortive kernles decreased.Grain number per ear,grain weight and grain yield were increased significantly.The yield increments of zinc,manganese and boron was 7.55%~12.25%,6.22%~7.62%and 2.43%~4.32% respectively.7.In summary,zinc had most significant effect on maize plant growth and yield among these three micronutrients,and the second one was manganese.The application of the three micronutrients in the production of high-yield summer maize had a wide prospects.