HomeInternational Rice Research Notesvol. 22 no. 2 (1997)

Correlation and Heritability Grain and Leaf Characters in Indica Rice in High Yield Conducive Environments of Yunnan, China

Zeng Yawen | Chen Yong | Liao Xinhua

Discipline: Agriculture



China has bred 15 cultivars, including Guichao 2 and Yue 517, whose yields have exceeded 15 t ha-1 with single cropping of middle rice in the Jingshajiang region (e.g., Yuanmou, Yongsheng), because of favorable climatic conditions: annual mean air temperature, 17.9-21.9°C; >10°C cumulative temperature, 5954.1-7986.0°C; >18°C accumulated temperature, 4126-6050°C; annual sunshine, 2179.4-2736.0 h; annual rainfall, 449.6-801.2 mm; annual evaporation of 2636-3820 mm is 3.4-6.0 times rainfall; and relative humidity, 54-64%. During the rice cropping season, about 5 mo from April to August, the >10°C cumulative temperature is 3822.4-4100.0°C. For example, single cropping of middle rice at Taoyuan township in Yunnan Province requires a cumulative temperature of 1050°C from sowing to transplanting, 2150°C from transplanting to full heading, 880°C from full heading to maturation, and rainfall from 411.5 to 424.4 mm. Yield components (l5-17 t ha-1) were 4,710,000±103.5 panicles ha-1, 133±28.6 grains panicle-1, and 27.6±2.3 g 1000-grain weight-1. Fertilizer is applied heavily at early stages, lightly at middle stages, and supplementary at late stages (207.0 kg N ha-1, 65.3 kg P ha-1, 124.5 kg K ha-1) combined with increased foliar spray.