- 作者： 楊居成
- 作者服務機構： 國立中興大學植物學系
- 中文摘要：
本試驗以臺南五條（?型稻）及臺中秈三號（秈型稻）為材料，於三個年度期
間，利用二氧化碳氣體交換法，探討臺中地區第一、二期作稻?落，各生長期日間
光合率、夜間呼吸率及光合成系之變化。試驗結果摘要如下：(1)一期作稻保持每天
13小時行光合作用；而二期作稻自最大分?期12.5小時漸減至成熟後期9.5小時。
一期作稻具有充足之強日照環境，而二期作稻自成熟期後，日照急速下降。(2)抽穗
期前兩種之光合率，二期作均大於一期作，但自抽穗期後，一期作則皆大於二期作
且二者之差異逐漸增大。(3)兩稻種二期作之呼吸率均大於一期作，且二期作保持較
穩定之呼吸率。(4)兩稻種一期作各生長期呼吸率對光合率之比值為0.4左右，且無
明顯之變化；但二期作臺南五號自孕穗期0.43增至最後1.8，臺中秈三號自0.46升
至2.6。(5)一期作稻葉片較二期作者為厚，葉綠素含量也較高，故一期作葉部吸光
率較高，而利於光合作用進行。結果葉部具有較多同化物，且輸送至穀粒之量亦較
大，因而提高穀粒充實率及穀收量，C - 英文摘要： The diurnal exchange rate,Photosynthetic system, and yield maincomponents of the first and secondcrop of Tainan No. 5 and TaichungNative No. 3 rice cultivars were deter-mind for three-year period. The resultsindicated:(1) The diurnal photosyntheticperiod of the first crop maintained at13 hrs after the maximum tilleringstage, while the period of the secondcrop became shorter from 12.5 to 9.5hrs. The solar light intensity for thefirst crop maintained high, while thesecond crop obtained the lower oneafter the early maturing stade. (2) Thephotosynthetic capacity of the first cropbefore the heading stage was lowerthan that of the second crop. On thecontrory, the first crop was higherthan the second one after the headingstage. The different value became thelargest one at the late maturing stage.(3) The respiration rate of the first cropwas lower than that of the second cropafter the maximum tillering stage. Thevalue maintained steadily through allfive different growth stage. (4) Theratio of the respiration rate to thephotosynthetic rate of the first cropmaintained at 0.4; however, the valueof the ratio increased from 0.43 to 2.6after the booting stage. (5) The lightabsorption efficiency of the first cropleaf for performing photosynthesis washigher than those of the second crop.This was due to the former maintainedthe thicker leaf and higher content ofchlorophyll. The above-mentioned re-sults show that the first crop of riceproduce mote assimilatory substancesand translate more nutrient from leafto the growing grain than those ofthe second crop. These lead to thehigher grain yield of the first crop thanthat of the second one about 26%.
- 中文關鍵字： --
- 英文關鍵字： --
