珍汕97/明恢63重组自交系群体根系性状对产量的影响

Effects of Root Characteristics of the Population of Recombinant Inbred Lines Derived from Zhenshan 97/Minghui 63 on Grain Yield

在群体水培条件下 ,以珍汕 97 明恢 63重组自交系群体的 2 0 4个株系 (F1 2 ,F1 3)为供试材料 ,研究重组自交系群体抽穗期根系有关性状与产量的关系 ,以期为水稻根系改良和根系数量性状基因定位提供依据。结果表明 ,影响产量的主要根系性状为单株根系活性、颖花根活量、每株根干重、最长不定根长、众数根长、每条不定根长及每条不定根粗 ,其中以单株根系活性对产量的影响最大 ;增加单株根系活性、每株根干重、最长不定根长和每条不定根粗能显著提高产量 ,增加颖花根活量、每条不定根长和众数根长将使产量显著下降。增加高产类型水稻抽穗期的每株根干重、每条不定根重、单位长度根重及单株根系活性能显著提高产量。每株根干重与高产水稻关系密切 ,而每株不定根数则与低产水稻关系密切。颖花根活量的增加对高产水稻株系的产量有提高作用 ,对中低产水稻则有负面影响。

To illustrate the root characteristics of high-yielding rice and provide further experimental base for the genetic improvement of rice root traits, the population of 204 recombinant inbred lines (RILs, F_(12), F_(13)) derived from Zhenshan 97/Minghui 63, an elite Indica hybrid rice combination in China, was solution-cultured and the relationship between yield formation and root morphological and physiological traits was systematically analyzed. The results showed as follows: (1) The major root characters which significantly affected grain yield in RIL population were: root activity per plant, root activity per spikelet, root dry weight per plant, length of the longest adventitious root, length of mode roots, length and thickness per adventitious root, among which root activity per plant had the most significant effect on grain yield. Raising root activity per plant, root dry weight per plant, length of the longest adventitious root and thickness per adventitious root resulted in significant increase of grain yield in RILs, while increase in root activity per spikelet, length per adventitious root and length of mode roots could lead to obvious decrease of grain yield in this population.(2) Grain yield of high-yielding lines in RIL population could be enhanced by raising root dry weight per plant, dry weight per adventitious root, root dry weight per unit length and root activity per plant. Raising root activity per spikelet could significantly increase grain yield of high-yielding lines but decrease grain yield of low-yielding lines in RIL population. Root dry weight per plant had a positive correlation with grain yield in high-yielding lines, while the number of adventitious roots per plant had the same important effect on grain yield in low-yielding lines.