从配合力分析探讨甘蔗家系抗黑穗病的育种潜力

THE BREEDING POTENTIAL OF THE SMUT RESISTANCE OF SUGARCANE STRAINS AS REVEALED BY COMBINING ABILITY ANALYSIS

采用5×4不完全双列杂交设计选配的第1次无性种茎为试验材料,在人工浸渍接种黑穗病菌条件下,估算了9个亲本及其组合在新植蔗和宿根蔗的配合力效应。结果表明:①20个家系抗性差异较大,以CP67/412、ROCl为母本的半同胞家系表现较强抗病性,而以CP72/1210、CP65/357为母本的半同胞家系表现一定感病性;②甘蔗抗黑穗病遗传是由加性效应基因和非加性效应基因共同控制;③发现CP67/412、ROClgca效应值较高,CP57/614次之,均具有可作为抗源亲本的育种潜力,④根据配合力总效应值评价组合,认为CP67/412×崖84/153、ROCl×崖71/374、CP67/412×崖71/374、ROCl×崖84/153、CP67/412×崖73/512、CP57/614×崖84/153是抗黑穗病较强的组合,可用于今后抗黑穗病育种计划。

The first clones of 20 sugarcane hybrid lines from a 5 × 4 incomplete dialled design were used as experimental materials. After dipping inoculation,the resistance of their new plant canes and ratoon canes to smut were scored and the combing ability for smut resistance of 9 parental lines and their hybrid combinations were calculated. The results indicated that (1)The resistance of 20 hybrid lines were quite different from each other. Half-sib lines with CP67/412 and ROC1 as their maternal parents showed better resistance whereas those with CP72/1210 and CP65/357 as their maternal parents were rather susceptible; (2)The smut resistance of sugarcane was controlled jointly by additive and nonadditive;(3)CP67/412,ROC1 and to some extent CP57/614 showed higher gca effect ,and consequently had better potential as sources of smut resistance; (4)According to evaluation of the total ca effect,CP67/412 ×Ya 84/153,ROC1× Ya71/374, CP67/412 × Ya71/374, ROC1 × Ya84/153, CP67/412 × Ya73/512 and CP57/614 × Ya 84/153 were considered to be the best resistant combination and could be used in sugarcane breeding program for smut resistance.