RICE SCIENCE ›› 2008, Vol. 15 ›› Issue (2): 110-118 .

• Research Paper • Previous Articles     Next Articles

Analysis on Dry Matter Production Characteristics of Super Hybrid Rice

WU Wen-ge 1, 2; ZHANG Hong-cheng 2; QIAN Ying-fei 2; CHENG Ye 2;WU Gui-cheng 2;
ZHAI Chao-qun 2; DAI Qi-gen2
  

  1. 1 Rice Cultivation Technology Innovation Center in the Middle and Lower Reaches of the Yangtze River, Ministry of Agriculture/ Rice Research Institute, Anhui Academy of Agricultural Sciences, Hefei 230031, China; 2 Agricultural College, Yangzhou University, Yangzhou 225009, China
  • Received:2007-11-07 Online:2008-06-28 Published:2008-06-28
  • Contact: ZHANG Hong-cheng
  • Supported by:
    the State Science and Technology Program of Grain Harvests in China (Grant Nos. 2006BAD02A06 and 2006BAD02A04).

Abstract: Six middle-season indica hybrid rice combinations, including five super hybrid rice combinations with the high yield about 10.5 t/ha and a check hybrid rice combination Shanyou 63 with a yield potential about 9.5 t/ha, were used as materials to study the dry matter production characteristics. The super hybrid rice showed a high ability in dry matter production and accumulation and its yield enhanced with the increase of dry matter accumulation. The advantage period of dry matter production in the super hybrid rice was mainly at the middle and late growth stages compared with the check. The grain yield had no significant correlation with the dry matter accumulation before the elongation stage while had a significantly positive correlation with the dry matter accumulation from the elongation to maturity stages in super hybrid rice. There were more dry matter in vegetative organs at the heading stage in the super hybrid rice but its contribution to yield (apparent conversion percentage) was averagely 4.3 percent points lower than that in the check. For crop growth rate (CGR), the comparative advantage of super hybrid rice was at the middle and late stages, especially after flowering. Moreover, as the rising of leaf area index (LAI) and leaf area duration (LAD), CGR enhanced. The total LAD and the mean of LAD per day of super hybrid rice was about 14.79% and 10.31% higher than those of the check, respectively. The results indicate that the high yield of super hybrid rice mostly comes from the products of photosynthesis after heading, which is shown by the increased CGR at middle and later stages. It is suggested that LAD character might be used to better explain the advantage in the dry matter production of super hybrid rice than LAI.

Key words: super hybrid rice, dry matter production, crop growth rate, leaf area duration, leaf area index, net assimilation rate