二期作水稻光合成物質的生產、分配及與產量間的關係

The Relationship between Photosynthetic Production during Grain-filling and Grain Yield of the Second Crop Rice

楊藹華(A. H. Yang) ； 梁文實(W. S. Liang) ； 魏夢麗(M. L. Wei) ； 劉大江(D. J. Liu)

《中華農業研究》 32卷3期 (1983/09) Pp. 209-218

https://doi.org/10.29951/JARC.198309.0002

摘要

於70年二期作在羅東、臺中與屏東共栽培4個水稻品種，自抽穗期至成熟期間，每十天取樣一次，分析植株不同器官內乾物質、全氮及非構造性碳水化合物(TNC)含量變化。以瞭解二期作水稻穀粒充實期間光合成物質的生產能力及分配，對其增產之可能性加以評估，並於不同地區間進行比較。
水稻穀粒充實期間，葉片內的氮濃度明顯下降，莖稈的降低幅度較小，穗部則無顯著變化。葉片TNC濃度的變異頗不規則，莖稈部位極顯著的下降，表示有多量碳水化合物向穗部轉移。三個地區的稉稻全株乾物質生產量均在6-8g之間，臺中秈10號則高達12g，但與產量的關係並非完全一致，可能與乾物質的分配劾率有關。非構造性碳水化合物的淨生產則與產量有密切之關係，臺中地區的兩個秈稻品種，每株可增加14-18g的TNC，產量爲29-33g，其他兩個稉稻品種則分別爲6-11g之TNC與16-20g的穀產量。
羅東地區臺南5號產量最低的原因爲一穗穎花數太少，臺中地區秈稻高產則歸因於穗數或一穗穎花數較多。收穫指數介於0.52-0.67之間，且產量越高，收穫指數亦高；氮收穫指數(har vest N index)也有相同的表現，即產量高時，穗部含氮量佔全株含氮量的比值增高，但二老間之因果關係則未能明瞭。非構造性碳水化合物收穫指數(harvest TNC index)高達0.91-0.97，以羅東臺南5號最低，表示部分葉片所生產的TNC儲存於莖稈，未能充份轉運至穗部；而較高產水稻品種殘留營養器官內之TNC僅爲3-4%，可能無法充份供應穗部需要，亦即光合成能力成爲產量限制因子。
就乾物質之生產、分佈及TNC的累積量與趨向而言，如何提高穀粒充實期間的光合成能力以因應穗部發育的需求，可能對提高二期作水稻產量極爲重要，分配勁率亦值得注意，將繼續進行研究。

並列摘要

Experiments were held in the 2nd crop, 1981 at three locations (Lotung, Taichung and Pintung) to investigate the potential of dry matter and total nonstructural carbohy drate (TNC) production and their relationship with grain yield in rice.
Nitrogen concentration in the leaf blades was low at heading and decreased continu Qusly during grain-filling whereas changes in TNC concentration if the leaf blades were erratic during the same period. Culm TNC was over 20% at heading but decreased to 3-4% at maturity, indicating marked retranslocation to the developing panicles. Net dry matter accumulation was about 6-8 g per hill with the only exception of Taichung sen No. 5 grown in Taichung area (12 g). However, no definite relationship was found between grain yield and the amount of dry weight increase during grain filling. In contrary. TNC production was correlated with grain yield and could be used as an index o the efficiency of dry matter distribution.
Low yield of Tainan No. 5 at Lotung area was due to fewer number f spikelets pep panicle. The attribution of high grain yield of indica rice at Taichung was more panicle number or spikelet number per panicle. Harvest index (HI) ranged between 0.52 to 0.67 and was positively correlated with yield. Similar result was found on harvest nitrogen index (HNI). However, high HNI was considered as the result of high grain yield rather than the cause of it. Harvest TNC index (HTNCI) was as high as 0.91-0.97. Lowest value of HTNCI was observed on Tainan No. S rice at Lotung area, suggesting inefficient translocation of available carbohydrates from vegetative organs to panicles. In general, less than 4% of TNC remained in culms at maturity which indicated that photosynthate production during grain-filling might not be able to meet the demand of panicles.