Performance of New Released Winter Wheat Cultivars in Yield: A Case Study in the North China Plain

Abstract

Genetic gains play important roles in crop yield improvement. This study used the observation data from two cultivar test sites under limited irrigation and without irrigation for 11 seasons from 2002 to 2013 in the North China Plain (NCP) to examine the yield and yield characters of newly released winter wheat (Triticum aestivum L.) cultivars as compared with the control (CK). Large seasonal yield variation of – 40 to 37% was observed due to the fluctuations in the weather condition. The average yield of newly released cultivars (NRs) was similar to that of the same control cultivar at the two sites during the 11 seasons, indicating that NRs had characters that responded to seasonal weather variation similarly and they might not be better in offsetting the negative climatic effects on grain production as compared with the CK. However, there were always cultivars that out‐performed the control in yield around 10% for the 11 seasons, indicating the possible genetic gains in using new cultivars. The number of seeds per area played a critical role in determining the final yield of winter wheat, which was significantly affected by the weather conditions during the seedling and vegetative growing stages. Selecting cultivars with high vitality at seedling stage was important in this region. Under rain‐fed conditions, the significant positive correlation (P < 0.01) of percentage of the roots in deep soil with the final yield indicated the selection and breeding for root traits could result in a yield benefit. Two sites of cultivar test was used to analyse the possible genetic gains. Average yield of new released cultivars was the same with the control cultivar. Cultivars performed better usually had a higher seed numbers per area. Cultivars performed better under rain‐fed condition had a prolific root system. Weather factors of temperature and sunshine hours being significantly related to yield.