桑树优良新品种云桑5号的选育初报

Preliminary Report on Breeding of New Mulberry Variety Yunsang 5

云南省蚕区具有明显的高原立体气候,选育适应云南蚕区种植的优质、高产桑树新品种,对于云南蚕桑产业的可持续发展具有重要意义。利用云南蚕区现行优良桑树品种及优异桑种质资源作为亲本材料,采用杂交和化学诱导染色体加倍的方法,育成人工同源四倍体桑树新品种云桑5号。新品种于2015—2017年在云南省多点进行区域适应性种植试验,在草坝镇试验点的单位面积产叶量比对照桑品种湖桑32号和农桑14号分别增产42.63%和19.01%,桑叶养蚕的万头蚕产茧量和茧层率与2个对照品种比较均无显著差异;新品种在永仁县、巧家县、陆良县、楚雄市和鹤庆县按照当地的栽植模式其产叶量较农桑14号高出16.08%～18.75%。新品种还具有发芽期早、发条力强、生长旺盛、叶片肥厚等特性,但对桑褐斑病和桑白粉病的抵抗力稍弱,需要及时采摘适熟叶以降低病害的影响。

The sericultural area of Yunnan Province is typified by its stereoscopic climate of plateau. It is of great significance for the sustainable development of sericulture industry in Yunnan Province to breed new mulberry varieties with high quality and high yield,which are suitable for planting in sericultural area of Yunnan Province. By using the current excellent mulberry varieties and superior mulberry germplasm resources in sericultural area of Yunnan Province as parent materials,an artificial autotetraploid mulberry variety Yunsang 5 was obtained by using hybridization and chemical mutagenesis to induce chromosome doubling. The results of regional adaptation test at multiple sites in Yunnan Province from2015 to 2017 showed that the leaf production per unit area of this artificial tetraploid mulberry variety increased by42. 63% and 19. 01% respectively compared with two control mulberry varieties Husang 32 and Nongsang 14 at Caoba Town,and there were no significant differences in cocoon weight and cocoon shell rate per 10 000 larvae between Yunsang 5 and the two control mulberry varieties. In the sericultural regions including Yongren County,Qiaojia County,Luliang County,Chuxiong City and Heqing County,in accordance with the local planting patterns,the leaf yield of Yunsang5 increased by 16. 08%-18. 75% as compared with Nongsang 14. Moreover,the new variety has the characteristics of early bud germination,excellent sprouting ability,high growth vigor and thick leaves. However,it has relatively low resistance to mulberry brown spot and powdery mildew diseases. Picking ripe leaves in time is suggested to reduce damage caused by these diseases.