糖能兼用甘蔗新品系的性状遗传分析及综合选择

为选育糖能兼用甘蔗新品种,以自育的27个新品系和2个对照品种为试验材料,通过调查测定出苗率、分蘖率、宿根发株率、枯心苗率、黑穗病发病率、株高、茎径、公顷有效茎数、田间锤度、甘蔗蔗糖分、甘蔗纤维分、公顷蔗茎产量、公顷产糖量和公顷总可发酵糖量等性状,对各性状进行方差分析、遗传变异和遗传相关分析,对公顷产糖量和公顷总可发酵糖量进行多性状指数选择,并与单性状选择做比较。结果表明:除新植枯心苗率之外,所测性状在试验材料间均具有显著或极显著的差异,公顷有效茎数、公顷蔗茎产量、公顷产糖量和公顷可发酵糖量的遗传变异系数较大且广义遗传率较高,株高、茎径和田间锤度的遗传变异系数较小且广义遗传率较低。公顷有效茎数与公顷蔗茎产量、公顷产糖量、公顷可发酵糖量的表型和遗传相关性达显著水平。用指数选择法进行综合选择,13个新品系入选,且有8个入选材料的新宿平均公顷产糖量和新宿平均公顷可发酵糖量均超过双对照,指数选择法能获得较高的遗传增益,可用于糖能兼用甘蔗新品种的评价选择。

Genetic analysis and comprehensive selection of new sugar and energy cane lines

In order to develop new sugar and energy cane varieties,27 new lines and 2 control varieties were selected as plant materials.Mutilple traits,including tillering,shoot in ratoon,dead heart seedling and smut incidence,plant height,stalk diameter,millable stalks per hectare (MSH),Brix,contents of sucrose and fibre,tons per hectare in cane (TCH),sugar (TSH) and total fermentable sugar (TFSH),were investigated.And further analyzes of variance,genetic variation and genetic correlation were also conducted.The index selection for TSH and TFSH was conducted by multiple traits,which was compared to single strait selection.The results showed that there were significant or highly significant differences among the investigated traits except for the rate of dead heart seedling.Both genetic variation coefficient and broad-sense heritability were higher in MSH,TCH,TSH and TFSH and lower in plant height,stalk diameter,and brix.The correlations of MSH with TCH,TSH and TFSH were significant.Thirteen new lines were selected based on comprehensive selection by using index selection method.Among which,8 new lines showed that the averages of TSH and TFSH in both plant and ratoon cane were higher than those in 2 control varieties,The results indicated that higher rate of genetic gains can be obtained by index selection method,which can be applied for evaluation of sugar and energy cane varieties.