甜瓜蔓枯病抗性聚合材料中防卫基因的表达分析  

The expression analysis of defense genes in the genes pyramided melon(Cucumis melo L.) resistance to gummy stem blight

作　　者：徐兵划 钱春桃[1] 王红英[1] 毕研飞 娄群峰[1] 张永兵[2] 伊鸿平[2] 陈劲枫[1] 

机构地区：[1]南京农业大学园艺学院/作物遗传与种质创新国家重点实验室,江苏南京210095 [2]新疆农业科学院哈密瓜研究中心,新疆乌鲁木齐830000

出　　处：《南京农业大学学报》2014年第5期63-68,共6页Journal of Nanjing Agricultural University

基　　金：国家自然科学基金新疆联合基金项目(U1178307)

摘　　要：蔓枯病是危害甜瓜的一种真菌性病害,由于存在生理小种的变异,携带单个抗病基因的甜瓜品种在生产中表现出抗性不足,本研究的目的是评价聚合基因材料的抗性,并分析相关防卫基因的差异表达。利用5份抗源创制8份聚合抗病基因材料,在采用梯度浓度孢子液接种鉴定的基础上,利用RT-PCR技术研究接种后苯丙氨酸解氨酶(PAL)基因、抗坏血酸氧化酶(APX)基因、几丁质酶(CHT)基因等防卫基因在聚合基因材料中的表达情况。结果表明:当接种浓度为5×109mL-1时,单一抗源已开始出现感病现象,而聚合基因材料仍表现高抗或抗,其中,890-398(PI511890×PI482398)和145-471(PI420145×PI140471)抗性最高。890-398中PAL基因表达高峰在1 d,早于PI420145和PI511890的2 d;抗、感及聚合甜瓜材料中的APX基因表达均在接种后3 d达到高峰,890-398中APX基因的表达水平约为对照‘白皮脆’的13.31倍,PI420145和PI511890中APX基因表达水平约为对照的10.00和9.38倍;CHT基因表达最高峰时,890-398中CHT基因的表达量约为对照的28.46倍,PI420145和PI511890约为对照的8.03和20.43倍。结论:甜瓜抗蔓枯病基因的聚合能提高其对蔓枯病的抗性,防卫基因在聚合材料中的高表达或早表达使其表现较高的抗性。本文创制的聚合基因材料可用于甜瓜的抗蔓枯病聚合育种,对甜瓜抗病育种具有重要意义。Gummy stem blight（GSB） is caused by Didymella bryoniae and is a serious fungal disease of melon （Cucumis melo L. ）. The resistance of the melon varieties that carry one GSB resistance gene might be reduced or even lost, because of the variation of D. bryoniae isolates. The objectives of this study were to critically evaluate the resistance to GSB of pyramided genes materials and to characterize the expression patterns of three defense genes associated with the resistance to GSB. We obtained eight materials combining two GSB resistance genes through the crosses of five single resistance gene sources. Seedlings were inoculated with gradient spores concentration of D. bryoniae. Based on the reaction of inoculation, we analyzed the expression dynamic of the defense genes by the RT-PCR method. The defense genes included phenylalanine ammonialyase （PAL）gene, ascorbic acid oxidase （APX）gene, chitinase（CHT） gene. The results showed that when the spores concentration was 5× 10^9 mL-1, the single-sources began to appear susceptible, and the pyramided genes materials still showed high resistance or resistance. The pyramided genes materials 890-398 （PI511890×PI482398） and 145-471 （PI420145×PII40471）showed the highest resistance. The expression peak of PAL gene in 890- 398 was at 1 d which was earlier than 2 d in PI420145 and PI511890. The peaks of APX gene expression of the resistance, suscepti- ble and genes pyramiding source were at 3 d after inoculation. The APX gene expression in 890-398 was approximately 13.31 times of the control＇ Baipicui＇ ,and P1420145 and PI511890 was about 10.00 and 9.38 times of the control,respectively. While CHT gene expression was at peak, the CHT gene expression in 890-398 was approximately 28.46 times of the control, PI420145 and PI511890 were about 8.03 and 20.43 times of the control, respectively. Conclusions： This study showed that pyramiding GSB resistance genes could enhance their resistance to GSB. The higher and earlier expression of defense genes i

关 键 词：甜瓜 蔓枯病 基因聚合 抗性鉴定 防卫基因表达 

分 类 号：S652.9[农业科学—果树学]