家蚕春用品种5号、4号的育成及其5·4×24·46四元杂交种的选配

THE BREEDING OF SPRING SILKWORM RACE No.5&No.4 AND THE PREPARATION OF TETRA HYBRID 5·4×24·46

采用杂交、回交、系统选育和五龄期高温冲击等育种方法，经多年的选择培育，育成了中系品种５号、４号，然后经测交鉴定选配成５·４×２４·４６，该对四元杂交种经多年江苏省实验室鉴定，四龄万蚕收茧量２２．５８ｋｇ、茧层量５．７１ｋｇ，比对照种苏５×苏６提高１４．２７％、１４．８９％，江苏省农村生产鉴定，张种产茧量４７．１１ｋｇ、产值５２６．１１元，比对照种苏５×苏６提高７．３４％、８．２９％。并获得全国桑蚕品种审定委员会鉴定通过。该品种强健好养，茧形大且匀整，茧丝质性状良好，综合经济性状优良。

Through selection and breeding by employing hybridization,backcrossing ,pedigreeselection and high temperature shock treatment during the 5th instar,two silkwormraces namely No.5 and No.4 of Chinese strain were bred.Consequently ,they were usedto prepare a tetra hybrid 5·4×24·46 after being test-crossed and identified.Laboratory identification in Jiangsu Province for many years showed that the tetrahybrid yielded 22.58 kg cocoons and 5.71 kg cocoon shells from 10 000 larvae of 4thage,14.27%and 14.89% higher than the control Su5×Su6,respectively.Identificationin farmers’rearing houses in Jiangsu Province showed that its cocoon yield was 47.11kg/case(output value 526.11 Yuan ),7.34%(8.29%)higher than the control.Thishybrid had passed identification of the National Mulberry and Silkworm VarietyEvaluation Committee.It was regarded as a strong and easy-to-rear variety with big anduniform cocoons,good filament properties and favorable comprehensive economiccharacters.