مرکز منطقه ای اطلاع رساني علوم و فناوري - مقايسه عملكرد آميخته هاي كرم ابريشم داخلي و خارجي با استفاده از دو نوع برگ توت اصلاح شده و بومي

چكيده لاتين :

Six Iranian silkworm hybrids (31*32, 103* 104, 107* 108, 109* 110, 111 * 116,113 * 118) and three silkworm hybrids from Japan, China and Thailand were tested. Two varieties of improved Japanese Ken Mochi (KM) and Guilan native mulberry were used for larva feeding. The cocoon weight, shell cocoon weight and percentage of cocoon shell of the samples were recorded individually and the obtained data were analyzed. The effects of genetic group, type of leaf and sex were statistically significant (P<0.05). The hybrids 113 *118 and 31*32 with 0.577g and 0.422g had the highest and the lowest larval weight of fourth instars, respectively and hybrids 111 *116 and 31 *32 with 1.33g and 0.937g had the highest and the lowest larval weight of fifth instars, respectively. Thai hybrids with 1.665g and 107*108 with 1.361g had the highest and the lowest cocoon weight, respectively. Whereas these two groups had the highest (0.381 g) and the lowest (0.287g) amount of shell cocoon weight, respectively. The Japanese hybrids had 23.3%, whereas 107* 108 and 109* 110 hybrids with 21.3% had the highest and the lowest percentage of cocoon shell, respectively. Those larva which had been fed with improved mulberry leaves produced cocoons weight of 1.577g, shell weight of 0.360g and percentage of shell cocoon of 23.3%; whereas the data for those larva which had been fed with native mulberry leaves were 1.501g, 0.328g, and 22%.The average cocoon weight, shell cocoon weight and percentage of cocoon shell for females were 1.700g, 0.350g and 23.3%, while these figures for male cocoons were 1.378g, 0.338g, and 24.7%, respectively. Hybrids 31*32 had the highest cocoon yield (67.14%) and the lowest percentage of mortality (32.86%). Whereas Japanese hybrids had the lowest cocoon yield (36.87%) and highest percentage of mortality (63.13%). The highest and lowest percentage of best cocoon belonged to 113x 118 (70.76%) and 107x108(44.81%) groups. With regard to the better performance of some Iranian silkworm hybrids in the Iranian experimental condition, imports of silkworm egg from overseas will not necessarily yield to an increase in production. In the case where it is necessary to import silkworm egg, it should be investigated the type of foreign hybrids which are best adapted Iranian climates. Different performance of Iranian hybrids under different feeding conditions, indicates the need for the evaluation of the hybrids in various rearing situations in order to identify the proper hybrids for each region.