Cucumis hystrix Chakr.×黄瓜种间杂种F_1及其双二倍体细胞遗传学特性及花粉育性研究  

Cytogenetic characteristics and pollen fertility of the interspecific hybrid F_1 and the amphidiploid from Cucumis hystrixChakr.×C.sativus L.

作　　者：陈龙正[1] 娄群峰[1] 张晓青[1] 钱春桃[1] 马云飞[1] 陈劲枫[1] 

机构地区：[1]南京农业大学作物遗传与种质创新国家重点实验室,江苏南京210095

出　　处：《南京农业大学学报》2006年第4期38-42,共5页Journal of Nanjing Agricultural University

基　　金：国家自然科学基金项目(30470120);国家高技术研究发展计划专项经费(2004AA241120);南京农业大学青年科技创新基金(KJ05006)

摘　　要：研究了野生种Cucumis hystrix（2n=2x=24）与栽培黄瓜C.sativus L．（2n=2x=14）种间杂种F1（2n=2x=19）及其双二倍体（2n=4x=38）自交S1～S4代的细胞遗传学特征及花粉育性。结果表明：减数分裂中期Ⅰ，杂种F1代花粉母细胞（pollen mother cell，PMC）染色体主要以单价体存在，染色体构型为：16．75Ⅰ＋0．5Ⅱ＋0．25Ⅲ＋0．13Ⅳ；双二倍体染色体构型以二价体为主，伴随着自交，平均每个PMC所含二价体比例逐渐增加，非二价体配对比例减少。四分体时期，F1代不能形成正常的四分孢子，主要以多分孢子形态存在；双二倍体以四分孢子为主，并随着自交世代的增加，其比例增高。花粉育性观察发现，随着自交世代的增加，双二倍体花粉育性呈增高趋势。以上结果暗示，双二倍体在遗传上逐渐趋于稳定；双二倍体PMCs在后期Ⅰ和Ⅱ普遍含有落后染色体、染色体桥及染色体不均等异常现象，可能是导致其花粉育性较低的原因。The cytogenetic characteristics and pollen fertility of the F1 hybrid （2n = 2x = 19） and selfed progenies （S1 - S4） of amphidiploid （2n = 4x = 38） from Cucumis hystrix Chakr. （2n = 2x = 24） ×C. sativus L. （2n = 2x = 14） were studied. The resuits showed that at metaphase Ⅰ （MⅠ）, the chromosome configuration of F1 hybrid was 16.75Ⅰ ＋ 0.5Ⅱ ＋ 0.25Ⅲ ＋ 0.13Ⅳ. Most chromosomes in the F1 were univalent, while in the amphidiploid they were bivalent. At metaphase Ⅱ, the F1 could not produce normal tetrads but mostly polyads, while the amphidiploid mainly produced tetrads. Moreover, the frequency of bivalents at MⅠ, tetrads at anphase Ⅱ and fertility of pollen increased during the selfing course that indicated the improved cytogenetic stability of the amphidiploid. It was also found that at anaphase Ⅰ （AⅠ） and AⅡ the PMC contained lagging chromosomes, bridge fragment, unequal disjunctions and nonsynchronized disjunctions in amphidiploid, which might cause the low pollen fertility.

关 键 词：甜瓜属 种间杂交 细胞遗传学 花粉育性 

分 类 号：S642.2[农业科学—蔬菜学]