RICE SCIENCE ›› 2012, Vol. 19 ›› Issue (4): 309-314.

• Research Paper • Previous Articles     Next Articles

Thermal Resistance of Common Rice Maintainer and Restorer Lines to High Temperature during Flowering and Early Grain Filling Stages

  1. National Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, China
  • Online:2012-12-28 Published:2012-10-15
  • Contact: TAO Long-xing
  • Supported by:

    the National Natural Science Foundation of China (Grant No. 30871473 and 31101116), the Project from the China National Rice Research Institute (Grant No. 2009RG003-5), the Projects from local government of Zhejiang Province, China (Grant Nos. 2008C22073, 2009C32048 and SN200806), and the Zhejiang Provincial Natural Science Foundation, China (Y3100060 and Y3100090)

Abstract: Fifteen common rice maintainer lines and 26 high-yielding restorer lines were used to evaluate their thermal resistance and fertility during flowering and early grain filling stages. The rice plants were subjected to high temperature stress (39–43 oC) for 1–15 d from main stem flowering. Based on the heat stress index, they were divided into thermal resistant lines, semi-thermal resistant lines, semi-thermal sensitive lines and thermal sensitive lines. Therefore, the maintainer lines K22B, Bobai B and V20B belonged to thermal resistant lines, whereas II-32B, Zhongzhe B and Zhong 9B belonged to thermal sensitive lines. For rice restorer lines, Minghui 63 had the highest thermal resistance, followed by R207, P32, P929, and the lowest thermal resistant lines P62-2-2, R8006 and P51. The correlation analysis indicated that the heat stress index was significantly correlated with seed-setting rate and abortive grain rate under heat stress, but not under natural conditions. This indicated that heat stress occurred during flowering and early grain filling stages mainly decreased the seed- setting rate and significantly increased the abortive grain rate in both rice maintainer and restorer lines.

Key words: rice , maintainer line , restorer line , heat stress , fertility , thermal resistance