神澤葉蟎為害桑葉對家蠶繭產量影響之評估

Abstract

本試驗於 1986 年 8 月至 11 月進行，當蠶種出庫前，在桑園中接種神澤葉蟎，造成 A、B、C、D 等4種不同之密度。自第 3 齡蠶起，飼以此桑葉。此時各處理第 6-10 葉片上每葉片之平均葉蟎密度分別為 8.8、29.2、88.8、103.9 隻，對照區為 2.2 隻。飼育家蠶之上繭數及食桑量在各處理間差異不顯著。C 及 D 區之熟蠶重及繭重(含蛹) 均顯著減少，而繭淨重及繭層率僅 D 處理顯著降低。亦即僅 D 區蠶隻之吐絲能力受到顯著影響。 During the fall of 1986, Tetranychus kanzawai was inoculated to mulberry right before the raising of silkworm to induce four different spider mite densities. Silk worms were fed with these mulberry leaves since the third instar. The mite densities, adults plus nymphs per leaf, were 8.8, 29.2, 88.8, and 103.9 for A, B, C, and D treatments respectively, and 2.2 for check at the begining of the third stadium of silkworm.