利用回交和标记辅助选择快速培育高油酸花生品种及其评价

Fast Development of High Oleate Peanut Cultivars by Using Marker-Assisted Backcrossing and Their Evaluation

【目的】高油酸育种是花生品质改良的重要方向,利用回交育种结合标记选择可快速实现现有推广品种的高油酸化改良,探讨利用这一技术体系进行花生高油酸遗传改良的实践和效率。【方法】以目前推广的优质高产抗病品种中花16、中花21、泉花551、徐花13为轮回亲本(母本,基因型AABB),以高油酸材料冀花13为非轮回亲本(父本,基因型aabb)配制4个杂交组合,一年种植两季并进行人工杂交或自交,夏季在武汉种植,冬季在湛江南繁基地种植,通过1次杂交、4次回交和1次自交得到BC4F2后代。利用PCR产物测序方法,鉴定杂交和回交后代的基因型:根据回交后代基因型分离规律及ah FAD2A与ah FAD2B序列高度同源性的特点,用引物F0.7/R3在一个PCR反应内同时高效扩增F1和回交后代(BC1F1-BC4F1)的ah FAD2A和ah FAD2B片段,并利用R3作为测序引物进行反向测序,读取测序峰图判别基因型,在回交后代中筛选基因型Aa Bb的后代作为下代回交父本。自交后代(BC4F2-BC4F3)基因型鉴定采用KASP分型,获得高油酸(基因型aabb)后代。对获得的基因型为aabb的高油酸后代与其对应轮回亲本进行重要农艺性状、品质和重要抗病性的调查和SSR标记检测。【结果】在3年时间内,4个组合分别获得10、5、6、8株BC4F2高油酸纯合隐性基因型(aabb)单株,通过一代自交获得相应的BC4F3株系,对获得的高油酸株系与轮回亲本进行植物学、农艺性状、品质和青枯病抗性的考察,最终,4个组合均获得了与轮回亲本综合性状最接近的株系,分别为ZJ019、ZJ109、ZJ160和ZJ805,其油酸含量为82.54%、79.85%、79.22%、和78.94%,可作为轮回亲本对应的高油酸新品种。另外,本研究还对中花16回交组合中获得的高油酸株系的遗传背景进行了SSR分子检测,发现ZJ019株系的回复率达94.8%,在该组合中回复率最高,这一结果与植物学、农艺性状鉴定的结果一致。【结论】利用连续回交、南繁加代和分子标记辅助选择等技术可在3年内快速实现现有推广花生品种的高油酸化改良。

【Objective】 The objectives of this research were（i） to establish an effective backcrossing approach combined with marker-assisted selection（MAS） of peanut high oleate breeding,（ii） to transform the elite peanut cultivars with normal oleate（NO） into high oleate（HO） ones in three years.【Method】Four cross combinations were designed named as BO-01, BO-02, BO-03 and BO-04 by selecting the elite peanut cultivars ZH16, ZH21, QH551 and XH13 with AABB genotype as recurrent parents, while JH13 with aabb genotype was selected as the high oleate donor parent. Via 1 cross, 4 backcrosses and 1 self-crossing, BC4 F2 progenies were obtained. According to the separation rule of backcross and high homology sequence of ah FAD2 A and ah FAD2 B, F1 and backcross progenies（BC1 F1-BC4 F1） were genotyped by sequencing of PCR products, in which ah FAD2 A and ah FAD2 B were amplified in one PCR reaction with F0.7/R3 primer pairs. Aa Bb genotype progenies were selected and used as male parent in next generation backcross. Self-crossing progenies（BC4 F2-BC4 F3） were examined by KASP（kompetitive allele specific PCR） to obtain aabb genotype progenies. Main agronomic traits, quality characters and disease resistance of aabb genotype progenies were investigated. The genetic backgrounds of progenies with aabb genotype derived from ZH 16×JH13 were evaluated with SSR markers. 【Result】In summary, during 3 years, we obtained 10, 5, 6 and 8 high oleate progenies with aabb genotype in 4 cross combinations, respectively. By evaluating their agronomic traits, quality and bacterial wilt resistance, high oleate peanut cultivars were obtained, which were highly consistent with their corresponding recurrent female parent. ZJ019, ZJ109, ZJ160 and ZJ805 with oleic content as 82.54%, 79.85%, 79.22% and 78.94%, are regarded as high oleic cultivars of ZH16, ZH21, QH551 and XH13.【Conclusion】By using backcross, off-season multiplication for advancing generation and molecular marker selection, normal oleate peanut cultivars were successfully and quickly transited into high oleate ones within 3 years.