寄主植物对草地螟幼虫的营养利用和中肠酯酶活性的影响

Effects of Host Plants on Nutritional Utilization and the Carboxylesterase Activities in the Larvae of Loxostege sticticalis L.

分别用藜(Chenopodium album L.)、大豆(Glycine max L.)、苜蓿(Medicago sativa L.)、甜菜(Beta vulgaris L.)和向日葵(Helianthus annuus L.)饲养草地螟,测定不同食料植物对草地螟幼虫的营养利用及中肠酯酶活性的影响。结果表明:取食灰菜的3龄幼虫,其相对生长率(0.91)、近似消化率(63.89%)显著高于取食大豆、苜蓿、甜菜和向日葵的;取食灰菜、大豆的食物利用率(分别平均为24.65%、24.96%)、食物转化率(分别平均为38.70%、41.41%)之间差异不显著;取食苜蓿的食物利用率(10.63%)和食物转化率(25.89%)显著低于取食其余4种植物的。取食大豆的5龄幼虫其体内血淋巴中的蛋白质含量显著高于取食其余4种植物的;取食向日葵的5龄幼虫其中肠的蛋白质含量显著高于取食其余4种植物的;取食灰菜和大豆的中肠酯酶比活力显著高于取食其余3种植物的。这些研究结果显示,灰菜是草地螟的最适宜寄主,其次分别为大豆、甜菜、向日葵、苜蓿。

In order to illustrate the effects of different plant hosts on nutritional utilization and activity of the carboxylesterase of the larvae of Loxostege sticticalis L.,L.sticticalis L.was fed respectively with Chenopodium album L.,Glycine max L.,Medicago sativa L.,Beta vulgaris L.,Helianthus annuus L..The results showed that there were significant differences in the nutrient status and activity of the carboxylesterase of the insect fed with 5 different plants.The relative growth rate（RGR =0.91） and the approximate digestibility（AD =63.89%） of 3 th instar larvae fed with the lambsquarter were significantly higher than those with the soybean,alfalfa,sugarbeet and sunflower.The efficiency of conversion of ingested food（ECI =24.65%,24.96%） and the efficiency of conversion of digested food（ECD =38.70%,41.41%） had no significant differences in larvae fed with the lambsquarter and soybean.The efficiency of conversion of ingested food（ECI =10.63%） and the efficiency of conversion of digested food（ECD =25.89%） of the larvae fed with alfalfa were significantly lower than those fed with the other 4 plants.Preliminary physiological reaction of testing 5 th instar larvae showed that the contents of protein in haemolymph of the larvae fed with the soybean were significantly higher than those fed with the other four plants and the contents of protein in mid-gut of the larvae fed with the sunflower were the highest.The esterase in mid-gut of the larvae fed with the lambsquarter and soybean were significantly higher than those fed with the other 3 plants.The results suggested that lambsquarter was considered the most appropriate host,followed by soybean,sugarbeet,sunflower and alfalfa.