稻水象甲成虫活动行为的日节律

Diurnal rhythm of adult behavior of the rice water weevil,Lissorhoptrus oryzophilus ( Coleoptera: Curculionidae)

为了摸清稻水象甲LissorhoptrusoryzophilusKuschel成虫在稻田中的Et活动行为节律，采用室外单头隔离饲养的方法，将成虫行为分为移动、取食、离水静息、触水静息和其他5个行为类型，每30min观察记录1次，从2012年4月30日至5月4日连续观察5d，共获得7200个行为数据。结果显示：稻水象甲越冬成虫行为的日时间分配以离水静息行为最多（47．83％），移动行为最少（5．64％），各行为的时间分配存在极显著差异（P〈0．001）。离水静息行为最高峰值在23：30（72．67％），最低值在7：30（14．67％）；触水静息行为最大峰值在7：30（75．33％），19：00还有一个小高峰（37．33％）；取食行为在15：00达到最高峰（26．67％），在21：00达到第2个高峰值（18．00％）；移动行为在22：00—9：00较少（0～4．00％），从9：30开始持续增加，在17：00达到最高峰（20．00％）；其他行为在1．33～18．67％之间波动。离水静息、移动、取食和其他行为白天和黑夜存在极显著差异（P〈0．001），但触水静息行为白天和黑夜无显著不同（P=0．834）；上午、中午、下午和晚上4个时间段之间各行为也有显著差异（P〈0．001）。在空间上，离水静息行为在叶片上最高，移动行为以水中最高，取食行为仅发生在叶片上，离水静息、移动和取食在水稻不同部位存在极显著差异（P〈0．001）。水中发生触水静息、移动和其他共3种行为，以触水静息行为的日波动最大，3种行为在各时刻之间有极显著差异（触水静息和移动：P〈0．001；其他：P=0．002）；叶片上发生离水静息、移动和取食3种行为，以离水静息和取食行为的日波动较大且在各时刻间具有极显著的差异（P〈0．001）；茎秆和瓶壁或封口纱布处主要发生离水静息和移动行为，所占比例均不高，但在瓶壁或封口纱布处的移动行为各时刻之间有极显著差异（P=0．008）。水中和叶片上是行为发生的主要空间，在水中行为的最高峰值（81．33％）与叶片的最低值（12．00％）出现时间相间，为7：30，一天中各时刻水巾和叶片上的行为呈交错性变化。结果提示，稻水象甲成虫活动行为受到时空变化的影响，且时间变化对其行为的影响较空间变化更为明显。

Diurnal rhythm of adult behavior of the rice water weevil, Lissorhoptrus oryzophilus Kuschel, was watched and recorded at 30 min interval by single rearing separately in field from April 30th to May 4th, 2012. All behaviors were divided into five types, i. e., moving （MG）, foraging （FG）, resting without contacting water （ ROCW）, resting with contacting water （RWCW） and others （ OT）, and 7 200 behavioral data were collected and analyzed. The results showed that the major behaviors were ROCW, accounting for 47.83% , while MG was minimum, accounting for 5.64%. Diurnal time among various behaviors were significantly different （P 〈 0. 001 ）. The peak of ROCW was recorded at 23：30 （72.67%）, the lowest was recorded at 7 ： 30 （ 14. 67% ）. Both RWCW and FG had two peaks, occurring at 7：30 （75.33%） and 19：00 （37.33%）, and 15：00 （26.67%） and 21：00 （ 18.00% ）, respectively. The peak of MG occurred at 17 ：00 （ 20.00% ）. The proportion of OT fluctuated from 1.33% to 18.67%. The results of the Mann-Whitney U test indicated that there were significant differences in ROCW, MG, FG and OT between day and night （ P 〈 O. 001 ）, but RWCW had no difference between day and night （ P = 0.834）. The further analysis also showed that five behaviors hadsignificant differences in forenoon, noon, afternoon and night during a day （P 〈0.001 ）. ROCW and FG mainly occurred on the rice leaf, while MG mainly occulted in the water. However, the results of the Kruskal-Wallis H test confirmed that ROCW, MG and FG had marked spatial variation in different parts （P 〈0.001）. RWCW, MG and OT were hund in the water, but the fluctuation of RWCW was the biggest. The three behaviors had significant differences among different time periods within a day （RWCW and MG： P〈0.001; OT： P=0.002）. ROCW, MG and FGwere found on the leaf, ROCW and FG were strongly regulated by time and their frequencies had significant differences among different time periods within a day （P 〈0. 001 ）. ROCW and MG were found in the stem and bottle wall or sealing gauze, however, the proportions of behaviors kept at a lower level. The behaviors of the rice water weevil were mainly hund in the water and on rice leaf, the peak of behaviors in the water （81.33%） and the lowest frequency of behaviors on the leaf （12.00%） occurred at the same time （7：30） , both showing rotation variation. These results suggest that both temporal and spatial variation could significantly influence the behaviors of the rice water weevil, and the effect of temporal variation is more significant than spatial variation.