台灣水田雜草雲林莞草(Bolboschoenus planiculmis)之生長及繁殖特性

Emergence, Growth, and Reproduction of Bolboschoenus planiculmis in Two Seasons

蔣永正(Y. J. Chiang) ； 方浩宇(H. Y. Fan) ； 蔣慕琰(M. Y. Chiang)

《中華民國雜草學會會刊》 30卷2期 (2009/12) Pp. 119-128

https://doi.org/10.6274/WSSROC-2009-030(2)-119

摘要

本研究主要探討水田難防治雜草－雲林莞草(Bolboschoenus planiculmis)於水稻一、二期作氣候下之生長與繁殖特性，作為擬訂防除策略之參考及依據。選擇圓球形直徑約1.5 cm之健康種球，種植於裝有一般田土之栽植盆內，定期調查萌發株數、株高與葉數及地下部新產生之球莖數等性狀。雲林莞草於2008年7月高溫下，種球種植後2日即開始萌芽，5日後萌芽數達50%，18日後全數皆萌發。2009年2月低溫下種植之種球，於4日後開始萌芽，8日後萌芽數達50%，全數萌發所需之時間為40日。低溫下種植之種球萌芽期超過一個月。單一種球種植後2-8週內，新植株數成直線增加，高溫下增加至16.2株，約為低溫環境下（8.7株）的2倍。8-16週期間，低溫下植株數仍緩緩增至12.7株，高溫下的植株數則維持在16株左右。顯示雲林莞草在高溫下的萌發速率較低溫下顯著快速。植株株高在種植後一個月內成迅速增加，高、低溫下均達到43 cm左右。四週後，高溫下的植株株高即不再增加，低溫下則持續增至第九週達61 cm之最高株高。植株葉數在種植後五週內增加達8葉左右，之後低溫下仍持續增至第13週達11葉之最高葉數，但高溫下葉數即不再增加，高、低溫下最終平均葉數相差約3葉。雲林莞草植株生物量變化，以單球總萌發株數之鮮重比較，低溫下以種植後4-8週的增加速率最高，其次為8-12週。高溫下僅種植後4-8週的鮮重明顯增加，8-16週後生物量開始降低。新種球發生於種後4-8週期間，但到16週仍持續產生新種球，其中以8-12週期間的種球增加率為最高，且高溫下產生之數目為低溫的1.8-2.1倍。本研究中雲林莞草植株株高、葉數及種球萌發的新植株數，均於種植後四週內顯著增加，之後低溫處理之植株雖會持續增加，但增加速率已大幅降低，地下部新種球的產生發生於種後四週，但直到四個月後種球數仍陸續增加，形成龐大的植株密度。因此田區內雲林莞草在發生初期的有效防治，為遏阻其快速繁殖及蔓延的適當時機。

關鍵字

雲林莞草 ； 球莖 ； 溫度 ； 萌芽 ； 生長 ； 繁殖

並列摘要

Bolboschoenus planiculmis is considered to be a noxious weed causing serious damage in crop field. The ability to reproduce by forming underground rhizome bearing spherical and elongated tubers provides this species with a unique competitive advantage over many crops. Growth and reproductive potential of B. planiculmis were examined outdoors using potted plants grown from single tuber in the first season (February to May, 2009) and the second season (July to October, 2008) rice crops. Tuber sprouted earlier and more uniformly in the second season test than in the first one. Time required for approximately 100% emergence of tested tubers was 40 and 18 days after planting for the first and the second season trial, respectively. A single tuber of B. planiculmis produced 8.7 and 16.2 shoots within 8 weeks after planting in 2009 and 2008, respectively. Higher and faster sprouting rate was observed when tubers were planted in the second season. Data on number of leaf, plant height and plant fresh weight demonstrated that vegetative growth of this weed in the first season test were consistently slower than those with the second season test. It took 8 weeks in the first season trial to produce biomass comparable to that of 4 weeks in the second season one. The growing period of B. planiculmis underwent until 12 and 4 weeks after tuber planting for the first and the second season trial, respectively. And it appeared with a faster growth rate during 8 weeks after tuber planting for two seasons. Seasonal variation in growth vigor was proposed associated primarily with the temperature condition at the early stage of seasons. The underground tuber started to appear at 4 weeks after planting in two seasons. Large amount of tubers were produced by B. planiculmis suggested their tremendous potential of multiplication in a single generation. In conclusion, with such extensive growth and reproductive potential, management strategies for B. planiculmis should focus on prevention, early detection and containment to reduce its competitiveness and spread.

並列關鍵字

Bolboschoenus planiculmis ； tuber ； temperature ； emergence ； growth ； reproduction