用萝卜苗作桃蚜植物寄主繁殖烟蚜茧蜂

Studies on the Use Radish Seedling to Propagate Peach Aphid for Mass Rearing Aphidius gifuensis

研究了用萝卜苗作桃蚜寄主植物繁殖烟蚜茧蜂的技术。结果表明 ,在温度 2 0～ 2 5℃、湿度 75 %的条件下 ,桃蚜的繁殖速度最快 ,1 0 d内即可获得大量的桃蚜。用不同虫龄的蚜虫接蜂 ,蚜龄越低寄生率越高 ;在不同温度中 ,2 5℃下寄生率最高。桃蚜的密度能影响烟蚜茧蜂的寄生率 ,密度在 1 0 0～ 2 0 0头时接蜂 1对 (雌∶雄 ) ,寄生率最高 ,可达 80 %。经连续 1 0代分别在不同蚜龄时繁蜂 ,虽然寄生率均随代数的增加而降低 ,但对低蚜龄时开始寄生的蚜茧蜂生长发育影响不大 ,其寄生率仍较其它蚜龄为高。在繁蜂室内用萝卜苗饲养桃蚜繁殖烟蚜茧蜂取得满意的结果。该技术设备简单 ,短期内可以获得较大量的烟蚜茧蜂 。

Method of using radish seedling as plant host to propagate peach aphid for mass rearing Aphidius gifuensis was studied in the laboratory. Results showed that the most favorable condition for the propagation of peach aphid was 20-25℃ and RH 70%. A. gifuensis prefered to oviposit on peach aphid of younger instars and the parasitization rate was also higher. 25℃ was the most favorable temperature for parasitizing. The host: parasite ratio could influence the parasitization rate. Best result was obtained when 100-200 aphids∶1 pair of parasite was used and 80% of the aphid could be parasitized. Continual rearing of A. gifuensis on peach aphid for 10 generations would decrease the parasitization rate of the aphid, but no distinct ill effect on the younger instar aphid was noted. Satisfactory results were obtained in a rearing room using radish seedling as plant host to propagate peach aphid for mass rearing A. gifuensis. Considerable amount of Aphidius wasp was obtained in a short period and used for the control of peach aphid.