GENETIC IMPROVEMENT OF WHEAT YIELD POTENTIAL AND ADAPTATION IN CHINA - Soybean and Wheat Crops: Growth, Fertilization, and Yield - page 186

I: Northern Winter Wheat Zone; II: Yellow and Huai River Valleys Facultative Wheat Zone; III:
Middle and Low Yangtze Valleys Autumn-Sown Spring Wheat Zone; IV: Southern Autumn-Sown
Spring Wheat Zone; V: Southwestern Autumn-Sown Spring Wheat Zone; VI: Northeastern Spring
Wheat Zone; VII: Northern Spring Wheat Zone; VIII: Northwestern Spring Wheat Zone; IX:
Qinghai-Tibetan Plateau Spring-Winter Wheat Zone; X: Xingjiang Winter-Spring Wheat Zone
Figure 1. Wheat zones of China (Jin, 1986; He et al., 2001).
G ENETIC I MPROVEMENT OF G RAIN Y IELD AND Y IELD C OMPONENTS
Autumn-sown region in China, including Zones I, II, III and V, is the most important
region, sharing more than 90% of wheat production. During the 2001-2002 and 2002-2003
crop seasons, six yield potential trials were conducted in Zone I located in Beijing, Zone II
located in Shijiazhuang of Hebei province, Jinan of Shandong province and Zhengzhou of
Henan province, Zone III located in Nanjing of Jiangsu province, Zone V located in Chengdu
of Sichuan province, respectively (Zhou et al., 2007a and b). Each trial consisted of the
leading cultivars from the 1949 to 2000 in each province. Only cultivars sharing more than
20% of wheat area in the respective province were included in the trials. The mean values of
grain yield and annual genetic grain were different in diverse wheat regions/provinces (Table
1). It showed that mean of grain yield ranged from 4.56 t/ha to 7.02 t/ha, average annual
genetic gain in grain yield ranged from 13.96 kg/ha/year to 72.11 kg/ha/year or from 0.31% to