In pot experiments of inter-subspecific rice hybrid Shanyou 413, higher level of IAA in rice plants, through IAA solution injected to the boot of the rice plant at booting stage, had little effect on the average weigh...In pot experiments of inter-subspecific rice hybrid Shanyou 413, higher level of IAA in rice plants, through IAA solution injected to the boot of the rice plant at booting stage, had little effect on the average weight and seed-setting of the superior grains located on the distal part of the panicle, nevertheless, significantly inhibited the filling of the inferior grains positioning on the secondary branches, which resulted in a longer "quiescent spell" before the beginning of the inferior grain filling and slower rate of the ovary expansion of the inferior grains. Consequently, the average weight and seed-setting of the inferior grains in treated plants was reduced to a large extent. Moreover, application of IAA to plants before heading promoted the abortion of the inferior florets. After heading, 3 top primary branches were clipped off and 20 μL lanoline, containing different quantities of IAA 0, 10 , 20, 30 and 40 ng/μL, were smeared onto the apex of the panicle axis. The results showed that clipping and only lanoline smeared decreased unfilled and partially-filled grain (UPG) percentage of the inferior grains on the secondary branches of the 3 base primary branches from 47. 7 % of check to 8. 2%. However, when the clipping and IAA applied, the UPG percentage was nearly restored to the level of check except the highest IAA quantity used, which indicated that as the influence on the filling of the inferior grains was concerned, IAA was able to substitute for the superior grains. It is deduced that the superior grains inhibit the filling of the inferior grains by the "apex dominance". When the inhibition occurs, the inferior grain filling can not be improved though the assimilate supply is quite rich. In field yield test of 1993-1994, uniconazole was proved to increase yield of intersubspecific rice hybrid Xieyou 413 and Shanyou 413 in advantage of above 10% to check, by ameliroating the filling of the inferior grains and resulted higher seed-setting. The possibility for fulfillment of the highest yieldingpot展开更多
利用“网袋法”（the mesh beg method）研究亚种间杂交稻 PE037×02428（PE）和品种间杂交稻汕优63（S63）在不同播期下的根系形态发育和生理活性。结果表明:在根系干物质累积、根系生理活性和穗粒性状上PE较S63具有杂种优势,但这...利用“网袋法”（the mesh beg method）研究亚种间杂交稻 PE037×02428（PE）和品种间杂交稻汕优63（S63）在不同播期下的根系形态发育和生理活性。结果表明:在根系干物质累积、根系生理活性和穗粒性状上PE较S63具有杂种优势,但这些优势最终未能转化成产量优势,主要是因为PE籽粒充实度不高所致。播期对根系形态发育和生理活性的影响不同:5/1O和5/4（月/日）播期有利于根系形态发育但根系生理活性较低,且后期衰退严重,其结实率和产量最低;而6/10和6/11播期有利于根系生理活性的提高,结实率和产量最高。相关分析表明,生育后期PE根系氧化力和SOD活性下降百分率与20cm土层内的平均温度存在显著正相关（r=0.933～0.972）,而与产量成显著或极显著负相关（r=-0.955～-0.999）。PE根系干物质累积优势对产量是一个负向优势。展开更多
文摘In pot experiments of inter-subspecific rice hybrid Shanyou 413, higher level of IAA in rice plants, through IAA solution injected to the boot of the rice plant at booting stage, had little effect on the average weight and seed-setting of the superior grains located on the distal part of the panicle, nevertheless, significantly inhibited the filling of the inferior grains positioning on the secondary branches, which resulted in a longer "quiescent spell" before the beginning of the inferior grain filling and slower rate of the ovary expansion of the inferior grains. Consequently, the average weight and seed-setting of the inferior grains in treated plants was reduced to a large extent. Moreover, application of IAA to plants before heading promoted the abortion of the inferior florets. After heading, 3 top primary branches were clipped off and 20 μL lanoline, containing different quantities of IAA 0, 10 , 20, 30 and 40 ng/μL, were smeared onto the apex of the panicle axis. The results showed that clipping and only lanoline smeared decreased unfilled and partially-filled grain (UPG) percentage of the inferior grains on the secondary branches of the 3 base primary branches from 47. 7 % of check to 8. 2%. However, when the clipping and IAA applied, the UPG percentage was nearly restored to the level of check except the highest IAA quantity used, which indicated that as the influence on the filling of the inferior grains was concerned, IAA was able to substitute for the superior grains. It is deduced that the superior grains inhibit the filling of the inferior grains by the "apex dominance". When the inhibition occurs, the inferior grain filling can not be improved though the assimilate supply is quite rich. In field yield test of 1993-1994, uniconazole was proved to increase yield of intersubspecific rice hybrid Xieyou 413 and Shanyou 413 in advantage of above 10% to check, by ameliroating the filling of the inferior grains and resulted higher seed-setting. The possibility for fulfillment of the highest yieldingpot
文摘利用“网袋法”（the mesh beg method）研究亚种间杂交稻 PE037×02428（PE）和品种间杂交稻汕优63（S63）在不同播期下的根系形态发育和生理活性。结果表明:在根系干物质累积、根系生理活性和穗粒性状上PE较S63具有杂种优势,但这些优势最终未能转化成产量优势,主要是因为PE籽粒充实度不高所致。播期对根系形态发育和生理活性的影响不同:5/1O和5/4（月/日）播期有利于根系形态发育但根系生理活性较低,且后期衰退严重,其结实率和产量最低;而6/10和6/11播期有利于根系生理活性的提高,结实率和产量最高。相关分析表明,生育后期PE根系氧化力和SOD活性下降百分率与20cm土层内的平均温度存在显著正相关（r=0.933～0.972）,而与产量成显著或极显著负相关（r=-0.955～-0.999）。PE根系干物质累积优势对产量是一个负向优势。
