- 期刊
- OpenAccess
寄主大小對四紋豆象（Callosobruchus maculatus）幼蟲競爭及產卵偏好之影響
Effects of Bean Size on Larval Competition and Oviposition Preference of Callosobruchus maculatus
摘要
四紋豆象雌蟲產卵在豆上，一般趨近於均勻分布，此種行為可以減少幼蟲的競爭，而使子代適存值增大。在本研究中首先探討4C6-4品系四紋豆象幼蟲在大、小紅豆中存活情形，以瞭解幼蟲資源競爭的程度。結果顯示，隨豆中幼蟲密度的增加，幼蟲的存活率即降低，尤其在小紅豆中，其幼蟲存活率下降最為劇烈，幼蟲所受競爭壓力最大。以不同比例大、小紅豆供給雌蟲進行產卵選擇，結果顯示，雌蟲產卵皆偏好大紅豆，但偏好程度隨大紅豆的比例下降而降低，且隨產卵日數的增加，對大紅豆的偏好性也逐漸降低。以產卵選擇模式預測之產卵分布變動情形與實驗觀測值相比較，推測雌蟲產卵法則為相對法則而非絕對法則。
並列摘要
Deposition of the bean weevil Callosobruchus maculatus (Fab.) on beans was found to be always in a nearly uniform distribution which reduced larval competition and increased larval fitness. To understand the competition between larvae, the survivorship of the 4C6-4 strain of bean weevil was investigated under different treatments, such as different bean sizes and number of larvae per bean. The results showed that the greater the number of larvae in a bean, the lower the survivorship of the larvae. This was especially true in smaller beans where resources are limited, and therefore the survival curve of larvae in smaller beans decline distinctly. Provided with various ratios of large and small beans, the female preferred to lay her eggs on larger ones. This preference decreased with decreasing ratios of large beans. Comparison between predicted and observed values of mean crowding showed that the oviposition behavior of the female was influenced by the relative encounter rate and the quality of beans; therefore, the female seemed to lay her eggs by a relative rule.