Adaptability of Varieties to Double-cropping in Early Spring and Late Summer

Abstract

Double-cropping is a new maize planting model in recent years.To explored the adaptability of varieties to the season and screen varieties suitable for double-cropping,we conducted trials in Laizhou,Shandong province,Jiaozuo and Xinxiang,Henan province in 2008-2010.The results showed that the accumulated temperature in early spring and late summer in different areas and years had the different impacts on each growth processes of species.The most varieties grown in early spring had higher yield than those in late summer,and most of the varieties seeded in the two seasons had the medium level of output(5 737-8 639 kg ha-1).In variety selection,growing period was an important index,but grain number per spike was not.Yinong 103 had high and stable yields in the early spring,and Zhengdan 958 could ensure stable production at the second growing season in the late summer.Meanwhile,the adaptability of one variety to the environment in early spring and late summer also can reflect the comprehensive performance of the variety in agronomy.