Abstract The growth of a stage-structured population of H. armigera was simulated for four variable conditions. Age-stage specific growth rate, and fecundity obtained from an age-stage, two-sex life table analysis were used to project the population growth for 60 days, starting with an average pair of young adults representing the population. Because the survival rate and fecundity used for the population projection were collected from the whole population, initializing the simulation with a pair of average individuals is appropriate. The projection results obtained by using the total number of eggs and the number of eggs that hatched were compared. The population projection obtained by using the total number of eggs provided an erroneous projection of the population growth. The population growth increased the shorter the life cycle, in the following order: artificial diet at 29°C > artificial diet at 25°C > hybrid sweet corn > asparagus. The number of cumulative insect-days and weighted insect-days were also calculated. This study demonstrated the advantages of a computer simulation based on the age-stage, two-sex life table in revealing stage-structured population growth. This knowledge is critical for the timing of integrated pest management.
摘要 本試驗在四種不同的條件下模擬玉米穗蟲Helicoverpa armigera (Hübner) 含齡期結構的族群增長。利用年齡齡期兩性生命表實驗所蒐集的生長及繁殖數據，以初羽化之單對雌雄為起始族群，模擬60天的族群增長。由於存活率及繁殖率的資料是由整體族群所得，利用單對初羽化雌雄作為起始，可模擬族群增長。本文比較以總卵數及實際孵化卵數模擬之結果。以總卵數進行族群模擬而忽略孵化率的差異會造成錯誤模擬結果。生活史越短在族群增長的速度上會越快，四種不同條件的族群增長速度依序為：在29°C下人工飼料 > 25°C下人工飼料 > 雜交甜玉米 > 蘆筍。我們也計算累積的昆蟲日 (insect-day) 及加權的昆蟲日。本文證實使用年齡齡期兩性生命表在族群模擬上的優點。這些知識對預測綜合害蟲防治時機非常重要。
| Key words: life table, insect-days, weighted stage size, simulation | | 關鍵詞: 生命表、每天的昆蟲量、加權昆蟲量、模擬。 |
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