头季稻齐穗期剑叶光合产物分配与再生稻产量的相关性

CORRELATION BETWEEN THE DISTRIBUTION OF PHOTOSYNTHATES OF FLAG LEAF AT FULL HEADING STAGE OF MAIN CROP AND YIELD OF POLINGENESIS RICE

以两系、三系杂交组合及其父本为材料,用14C同位素示踪法研究了头季稻齐穗期剑叶光合产物的分配及其与再生稻产量的相关性,结果表明：（1）头季稻齐穗期剑叶光合产物80%~90%分配到穗部,10%~20%残留于叶、茎,且主要残留在剑叶中,仅5%左右残留在茎鞘中,茎鞘各节间残留量一般表现为倒1〉倒2〉倒3〉倒4的趋势,倒2以下节间贮藏的光合产物占茎秆总量的1/3~2/3,品种（组合）间差异较大;（2）稻桩贮藏光合产物的52%~70%转运至再生稻体内,且分配至穗部的最多;（3）头季稻成熟期残留在茎鞘中,特别是倒2以下节间中的光合产物越多越有利于再生稻产量的提高;（4）本试验条件下,再生稻产量构成因素中,影响产量的首要因素是穗粒数。可见,选用穗粒数多、成熟期残留在茎鞘,特别是倒2以下节间中的光合产物较多的品种进行再生培植,有利于获得再生稻高产。

Two line and three line hybrid rice combinations and their male parents were used as materials to study correlation between the distribution of photosynthates of flag leaf at full heading stage of main crop and the yield of paling enesis rice by 14C trace echnique. The results showed that： （1） 80% - 90% of photosynthates of flag leaf at full heading stage was distributed to panicle in main crop and 10%- 20% of remnant was in leaves and stems, and the most was in flag leaves. Only about 5 % was in stems and sheathes, and the amount in different internodes of stems showed a trend of the 18st 〉 the 2nd 〉 the 3rd 〉 the 4th from the top. The ratio of remnant photosynthates in internodes below the 2nd to the total in stems was 1/3 2/3, and significant difference existed among varieties （combinations）. （2） 52 % - 70 % of remnant photosynthates in rice stubble was transported to palingenesis plants, and the part transported to panicles was most. （3） The more photosynthates distributed in stems and sheathes at maturity of main crop, especially in internodes below the 2nd from the top, the higher yield of palingenesis rice would get. （4） In this study, among four yield components, the grain number per panicle was the chief factor to affect yield of palingenesis rice. These results showed that choosing those varieties or combinations with bigger grain number per panicle and more remnant of photosynthates in stems and sheathes, especially in internodes below the 2nd at maturity of main crop would be benefit to gain higher yield of palingenesis rice under conditions in this study.