水稻行株距對褐飛蝨與其捕食性蜘蛛發生之影響

Effect of Rice Plant Spacing on the Population Density of Brown Planthopper and Two Predacious Spiders

邱瑞珍(Shui-Chen Chiu) ； 陳炳輝(Bing-Huei Chen)

《中華農業研究》 30卷3期 (1981/09) Pp. 270-276

https://doi.org/10.29951/JARC.198109.0007

摘要

本試驗自民國67年第二期作開始，連續4期作在本所試驗田進行水稻不同行株距對褐飛蝨與其天敵，兩種補食性蜘蛛之發生密度以及水稻產量等之影響。水稻之行株距分別爲20×15、25×25、30×30及35×35 cm。
試驗結果顯示第一期作因褐飛蝨發生數量少，各處理間均無顯著差異；67年與68年之第二期作均顯示褐飛蝨在20×15cm處理區之平均每分蘗上族羣數較30×30或35×35cm兩處理區爲多。再就水稻不同生育期褐飛蝨之族羣觀之，在水稻分蘗期以前，寬植（30×30與35×35cm）與密植(20×15cm)區之飛蝨發生量均無顯著差異。但進入孕穗期後，密植區之褐飛蝨族羣迅速上升。
又觀各處珍區內褐飛蝨之天敵，捕食性蜘蛛如六點狠蛛Lycosa pseudoannulata (B. et S.)與裂頭小盤蛛Oedothorax insecticeps(B. et S.)之發生數，無論在第一或第二期作，自孕穗期後，寬值區稻叢上之蜘蛛數均比密植區爲多，而且兩處理區之蜘蛛數差異顯著。

並列摘要

The effect of rice plant spacing on the occurrence of brown planthopper (BPH) Nilaparvata lugens and two predacious spiders, Lycosa pseucloannulata (B. et S. ) and Oedothorax insecticeps (B. et S. ), were studied at the paddy field in the Taiwan Agricultural Research Institute, Wufeng, Taichung. The experiment was begun from the second crop of 1978 to the first crop of 1980, and Tainung 67 rice was planted at 4 different spacings, viz. 20 × 15, 25 ×25, 30 × 30 and 35×35cm. No significant difference was found from the first crop of 1979 because of the low occurrence of BPH. And all the results were based on the records obtained from the second crops of 1978 and 1979.
Before rice tillering stage, the population densities of BPH in the 4 different spacing plots were similar to each other. However, during the booting stage, the density of BPH in the closest spacing plots (2015cm) increased much faster than those in the other spacing plots. Evidently, the difference of rice plant spacings influenced the population growth of BPH only after the plant size itself reached a certain density threshold. The final results indicated that the plots of 20×15cm had more BPH per tiller than the plots of 30×30 and 35×5cm.
After the beginning of rice booting stage, the population densities of both Lycosa and Oedothorax spiders were significantly higher in the widest spacing plot (35×35cm) than those in the closest spacing plot (20×l5cm). Which indicated that the close spacing environment is not suitable for the predacious spiders.
We conclude that the rice yield of the close spacing plot (20×15cm) is the highest if the density of BPH is low, and the yield of the currently used spacing (25×25cm) is the highest when the density of BPH is high.