脐橙与粗柠檬体细胞杂种果实类胡萝卜素、糖酸遗传的亲本偏向性

Parental Dominant Inheritance of Fruit Carotenoids,Sugars and Organic Acids in a Citrus Interspecific Allotetraploid Somatic Hybrid Between Bonnaza Navel Orange and Rough Lemon

采用高效液相色谱测定柑橘种间体细胞杂种[‘朋娜’脐橙(Citrussinensis Osbeck)+粗柠檬(C.jambhiri Lush)]和其两个融合亲本果实的类胡萝卜素含量,气相色谱测定可溶性糖及有机酸含量,并检测代谢过程中关键基因的表达,比较分析体细胞杂种果实品质遗传及基因表达特点。结果表明,体细胞杂种类胡萝卜素成分及含量均偏向粗柠檬亲本,柠檬酸、苹果酸积累量也偏向粗柠檬;而蔗糖含量处在中亲值;实时定量PCR技术检测类胡萝卜素代谢途径中的7个基因,其中4个基因在‘朋娜’脐橙中的表达量高于粗柠檬,环化途径中番茄红素ε环化酶基因(CitLcy-e)、玉米黄质环氧酶基因(CitZep)在体细胞杂种中表达量偏向粗柠檬亲本,显著低于‘朋娜’脐橙。可见粗柠檬遗传物质的表达在体细胞杂种中占主导地位。

Carotenoid compounds in the fruit pulp of somatic hybrid ‘Bonnaza’naval orange（Citrus sinensis Osbeck）＋ rough lemon（C. jambhiri Lush）and both parental species were quantitatively evaluated by HPLC,sugars and organic acids content were investigated by GC,and Real-time RT-PCR was used to detect expression levels of key genes involved in the carotenoid,sugars and organic acids biosynthetic pathways. Results revealed that strong dominance of rough lemon was found for citric acid, malic acid and carotenoid compound in somatic hybrid fruit,while sucrose content showed mid-parent value. Gene expression was higher in navel orange than in rough lemon for four of seven genes analyzed involved in carotenoid biosynthetic pathway. Rough lemon dominance was observed for expression of CitCrt,CitLcy-e and CitZep. These results indicated that rough lemon played a dominant role in inheritance of fruit quality characteristics and gene expression in the somatic hybrid.