- 作者： 林安秋; 陳建山
- 作者服務機構： 國立臺灣大學農藝系
- 中文摘要：
本省第二期稻作之產量比第一期作減少百分之二十五左右。其低產原因乃歸於穗數與結實百
分率之低減。本研究專就影響穗數之分蘗問題，特加試驗探討。臺南五號（?型稻）與臺中在來
一號（秈型稻）二品種供試，田間部分按一般慣行之栽培管理方法，在同一塊田地以相同肥料用
量下，分別種植一、二期水稻，同時在人工控制氣候室進行試驗，供為比較與印證。結果摘要如
下：
1.第一期稻作的初現分蘗期在移植後三十日左右，最高分蘗期在五十至六十日之間，而第
二期稻作之初現分蘗期較早，則在移植後十日左右，最高分蘗期在三十至四十日之間。臺南五號
與臺中在來一號之結果一致。二期稻作之結果與人工氣候室之高溫(30℃～25℃)，一期作則與
低溫(25℃～20℃)處理所得結果一致。
2.臺南五號兩期作之開始分蘗節位，單、三木植均位於主稈第五節位，期作間無顯著差異
。臺中在來一號第一期作之單、三本植之初現分蘗節位以第六節位居多，第五節位次之，然第二
期作則以第五節位居多。單、三本植之結果相同。
3.臺南五號第二期作之有效分蘗百分比，單、三本植均較第一期作為高。臺中在來一號略
異；單本植之第二期作較第一期作為高，但三本植之結果則與之相反。亦即是第二期稻作之有效
分蘗百分比並不比第一期作為低。
4.單本植之結果，一期稻作之分蘗次位可達到第四次分蘗，而第二期作則較一期作低一次
位，即到第三次分蘗為止。有效分蘗次位，前者可達三次分蘗，後者以二次分蘗為限，第三次分
蘗占極少數。
三本植之分蘗次位及有效分蘗次位，均較單本植同期作之結果低降一節位，二供試品種之結果相
同。
5.主稈最高分葉節位，單本植之結果，一期作可達到第十二節位，但二期作則低降一節位
，到十一節位為止。三本植又較單本植同期作之結果低降一至二節位。有效分蘗節位，均較最高
分蘗節位低降一節位，二品種之結果有相同傾向。又人工控制氣候室之結果，頗為相似。
6.主稈各節位之分蘗總數，第二期稻作均較第一期作為少。分蘗集中於中間節位（T ～
T )，但二期稻作較一期作低一節位，三本植又較單本植低下一節位。
7.人工氣候控制室之試驗結果，分蘗數以晝溫25℃，夜溫20℃最多，高溫（30℃～25℃)
條件下反而低減。二供試品種之結果，極為一致。
8.綜合試驗結果得知，氣溫過高乃是第二期稻作分蘗之最主要限制因素。
e - 英文摘要： The purpose of this study was to elucidatethe causes of low yielding in the second cropof rice according to the characteristics oftillering. Two variety of rice was cultured ata place in different crop season with the sameamount of chemical fertilizer and culturalpractices. Results in both the paddy field andphytotron were summarized as follows: 1. The first tiller emerged at 27-30 daysafter transplanting in the 1st crop, while the2nd crop took only 10 days. The formation ofmaximum number of tillers took about 50 to60 days in the 1st crop, but in the 2nd crop, itwas 10 days earlier than that of the 1st crop.It was corresponded to the results of phytotron. 2. The position of the first emerging tillerwas from the 5th node in Tainan No. 5, never-theless number of seeding per hill or cropseason. But the tiller of Taichung Native No. 1emerged more from node No. 6, and node No.5 respectively. Both of the two crop seasonshas the same results. 3. The percentage of the effective numberof tillers was higher in the 2nd crop than the1st crop in Tainan No. 5. In the case of Tai-chung Native No. 1，the result was same asTainan No. 5 in one seedling per hill trans-planted. But three seedlings per hill had thecontradictory results. 4. Most of the effective tillers emergedfrom the primary, secondary and tertiary tilleringin the 1st crop of one seedling per hill trans-planted. But in the case of 2nd crop, the tillerswere limited to the primary and secondarytillering. The results of three seedling per hillwas lower than that of one seedling. 5. The last tiller of the main culm was onthe position of 12th node in the 1st crop ofone seedling per hill, but in 2nd crop, it was anode lower than that, and it was even lower inthe results of three seedlings per hill than oneseedling. Two varieties had the same trend. 6. The total tillers on each node of themain culm was lower in the 2nd crop than thatof the 1st crop. Two varieties had the sameresult. 7. Under the controlled temperature condi-tion of phytotron, there was a greater amountof tillers at the lower day-night temperature(25℃-20℃), but decreased at higher tempera-ture (30℃-25℃). 8. We concluded that the temperature isthe limiting factor for tillering in the 2nd cropof rice.
- 中文關鍵字： --
- 英文關鍵字： --
