【摘要】 以粒重差异显著的2个籼稻品种和2个粳稻品种为材料,研究颖果发育过程中含水量、呼吸速率、脱氢酶活性、过氧化氢酶(CAT)和超氧化物歧化酶(SOD)活性与灌浆的关系。结果表明:1受精后的发育前期颖果含水量高,鲜、干重增加快,随着发育进程的增加和贮存物质的增多,含水量逐渐降低,鲜、干重的增加趋势逐渐减缓,日增重逐渐减少。2籼稻前期灌浆快于粳稻,停止灌浆的时间也早于粳稻;大粒灌浆速度始终快于小粒,停止灌浆的时间迟于小粒。3颖果含水量、呼吸速率随颖果发育进程的增加而下降,当含水量降低到200mg·g-1、呼吸速率降低到0.05μmol·(mg·h)-1(以单位时间单位鲜重所消耗的O2量计)左右,灌浆基本停止;呼吸速率与ATP含量呈正相关,且两者都与含水量呈正相关。4籽粒灌浆与颖果生理活性密切相关,颖果维持呼吸活性、脱氢酶活性、CAT和SOD活性的时间越长,籽粒接受灌浆物质的时间越长。5粳稻粒重与灌浆时间密切相关,粒重大的灌浆时间较长。更多还原

【Abstract】 <Abstrcat> Two varieties of Indica and two varieties of Japonica with significantly different grain weight were used in this experiment to study the relation between grain filling dynamic and its physiological activity. The result indicated that: ① At the primary stage, caryopsis water content was high, and decreased gradually during the rice grain filling. Fresh weight and dry weight of caryopsis increased quickly at the primary stage and then the increase trend was slowed down gradually. ② The grain filling rate in Indica was quicker than that in Japonica at the primary stage, but filling stopped earlier in Japonica. The grain filling rate with big grain weight was quicker than that with small grain weight during all the filling stage in rice and filling stopped later. ③ Caryopsis water content and respiratory rate decreased after anthesis, and filling stopped when water content decreased to 200 mg·g^-1 and respiratory rate decreased to (005 μmol·（mg·h）^-1), there was a positive relation between respiratory rate and ATP content, they both were positively related with water content. ④ There was a close relation between grain filling dynamic and its physiological activity. The longer the caryopsis kept respiratory rate, dehydrogenase activity, CAT activity and SOD activity, the longer the caryopsis kept filling. ⑤ The filling time of rice with big grain weight was longer than that of rice with big grain weight in Japonica.更多还原