Ear development characteristics of different Summer Maize Varieties under high temperature stress

• 1、College of Agronomy, Hebei Agricultural University
• 2、College of Plant Protection, Hebei Agricultural University

Abstract：The experiment was conducted in Xinji experimental station of Hebei Agricultural University in 2018. Using heat-resistant variety Nongda 372 and heat-sensitive variety Xianyu 335 as test materials, two treatments of high temperature and field control were set up. The difference of response of two types of maize varieties to high temperature stress was studied from the agronomic traits of tassel, pollen vigor and the development of female ear grain. The histomorphological characteristics of summer maize resisting high temperature stress were revealed, which could provide reference for high temperature-resistant and directional breeding of summer maize. The main results showed that high temperature stress shortened the growth process of maize, shortened the length of main panicle, increased the number of branches of tassel, decreased the size of tassel, volume of tassel and dry weight of tassel, increased the interval between male and female, hindered the pollination of tassel, decreased the amount of pollination, accelerated the rate of pollination, decreased the viability of pollen, changed the microstructures of pollen, affected the development of maize grain, and resulted in the decrease of yield per plant.

Keywords： High temperature stress Panicle Development Yield Summer corn