火龙果42份种质资源的倍性鉴定及基因组大小分析  

Ploidy identification and genome size analysis of 42 Pitaya germplasm resources

作　　者：丁一 王周雯 康绍玲 姜森荣 王猛 黄家权 李洪立[3] 胡文斌 汤华 DING Yi;WANG Zhouwen;KANG Shaoling;JIANG Senrong;WANG Meng;HUANG Jiaquan;LI Hongli;HU Wenbin;TANG Hua(School of Tropical Agriculture and Forestry,Hainan University,Haikou 570228,China;Sanya Institute of Breeding and Multiplication,Hainan University,Sanya,Hainan 572025,China;Tropical Crops Genetic Resources Institute,Chinese Academy of Tropical Agricultural Sciences,Haikou,Hainan 571700,China)

机构地区：[1]海南大学热带农林学院,海口570228 [2]海南大学三亚南繁研究院,海南三亚572025 [3]中国热带农业科学院热带作物资源研究所,海口571700

出　　处：《热带生物学报》2024年第3期306-314,共9页Journal of Tropical Biology

基　　金：海南省自然科学基金高层次人才项目(320RC487);海南省重大科技计划项目(ZDKJ2021014)。

摘　　要：为了满足火龙果的产业发展需求,必须开展火龙果高产优质新品种的选育工作。收集和评价火龙果种质资源,并开展火龙果的杂交育种,是火龙果育种的主要路径。火龙果种质资源多样,遗传倍性情况不明,对种质资源的倍性进行鉴定是育种创新不可缺少的环节。本研究建立了火龙果茎尖染色体制片体系,并采用茎尖染色体制片技术以及流式细胞技术对42份火龙果种质资源进行倍性鉴定。结果表明:1)火龙果茎尖染色体制片在前低渗时间为2 h、解离时间为1.5 h、酶解时间为1 h、后低渗时间为30 min时,染色体分散程度较好,背景清晰,没有出现重叠的现象,具有完整的细胞。2)火龙果茎尖倍性稳定,是最可靠的检测材料,老熟的茎条含有大量的四倍体和八倍体细胞,不宜做倍性鉴定材料。3)42份火龙果种质资源中有二倍体材料41份,四倍体材料1份,无三倍体材料。4)以‘金都一号’为参照,进行基因组大小的预估,发现有15份火龙果种质资源的1C-value(1C)≤1.34 Gb,为极小型基因组,27份火龙果种质资源的1C值在1.35~3.34 Gb之间,为小型基因组。In order to meet the needs of development of pitaya industry,it is necessary to develop numerous commercial varieties of pitaya with high yield and high quality through breeding and selection.The main way for pitaya breeding is to collect and evaluate pitaya germplasm resources for cross-breeding.Pitaya germplasm is diverse,and its genetic ploidy is unknown.The ploidy identification is indispensable to breeding innovation.Forty two accessions of pitaya germplasm were collected and their ploidy was identified by stem tip chromosome preparation technique and flow cytometry.When the current hypotonic time is 2 h,the dissociation time is 1.5 h,the enzymatic hydrolysis time is 1 h,and the post-hypotonic time is 30 min,the cells prepared are intact with good chromosome dispersion and clear background and without overlapping.The ploidy of the pitaya stem tip is stable,and the stem tip is the most reliable material for chromosome determination.The mature stems contain a large number of tetraploid and octaploid cells,and are hence not suitable for ploidy identification.Among the 42 accessions of pitaya germplasm there are 41 accessions diploid,1 tetraploid and no triploid.The genome size was estimated with accession‘Jindu No.1’as a reference.It was found that 15 accessions of pitaya germplasm were very small in genome size with the 1C-value(1C)being≤1.34 Gb while 27 accessions of pitaya germplasm were small in genome size with the 1C being in the range of 1.35 Gb~3.34 Gb.The identification of the ploidy of 42 accessions of pitaya germplasm might provide some reference for parent selection in pitaya cross breeding.

关 键 词：火龙果 种质资源 染色体制片技术 流式细胞技术 遗传倍性 基因组大小 

分 类 号：S667.9[农业科学—果树学]