普通小麦/山羊草属间杂交F_1的形态学及细胞遗传学研究

Study on Morphological and Cytogenetics of F_1 Hybrids between Triticum aestivum and Aegilops species

为了解普通小麦与山羊草属的杂交F1代的育性、细胞遗传学表现及育种利用潜力,以普通小麦7182和丰优1718为母本,分别以卵穗山羊草SY163和离果山羊草SY119为父本进行杂交,对杂交F1代的生育特性、染色体构型、田间条锈病抗性、F1自交和回交结实性等进行了分析。结果表明,F1代植株生长势较强,株型倾向母本,成熟期穗子易断,壳硬;杂交F1代高度不育,花粉可育率1.26%~3.54%,回交结实率2.08%~5.26%,仅普通小麦/卵穗山羊草自交结实,但结实率最高仅为0.25%。7182/SY163、7182/SY119、丰优1718/SY163、丰优1718/SY119杂交F1代花粉母细胞减数分裂中期I的染色体构型平均分别为31.11I＋1.90II＋0.03III、20.04I＋7.45II＋0.02III、30.08I＋2.40II＋0.04III、22.37I＋6.30II＋0.01III,说明普通小麦与2种山羊草杂交亲和性差,且可交配性主要由山羊草基因决定。田间条锈病抗性鉴定结果显示,F1代均对条锈菌混合小种高抗或免疫,这对于丰富小麦抗病基因资源有重要意义。

In order to investigate the compatibility, cytogenetic basis and breeding potential for selecting and utilizing intergeneric hybrid between wheat and Aegilops specices, two common wheat varieties 7182 and Fengyou 1718 were used as female parent crossed with Ae. geniculata and Ae. triuncialis. F1 was selfing and backcrossed with its female parent. The growth,fertility, cytogenetic characters, re- sistance to stripe rust,and the ripening rate of hybrid F1 selling and backcrossed lines were analyzed with the methods of measuring fixed plants,checking chromosome slide and staining pollen. The re- suits showed that hybrid F1 had stronger growth potentiality, maternal parent-like plant type, easy- broken spike at maturity, hard glumes, low pollen fertility with fertility rate of 1.26 %- 3.54% and the backcross seed setting rate of 2.08%- 5.26 %. Only common wheat/Ae, geniculata has cross- compatibility,with a maximun setting percentage of 0. 25%. The chromosome configurations in F1 PMC MI were 31.11Ⅰ ＋ 1.90Ⅱ ＋ 0.03Ⅲ,20.04I ＋ 7.45Ⅱ＋ 0.02Ⅲ,30.08Ⅰ ＋ 2.40Ⅱ ＋ 0.04Ⅲ and 22.37Ⅰ ＋6.30Ⅱ ＋ 0.01Ⅲ. It was suggested that the cross-compatibility are poor between the common wheat and two Aegilops species, and the compatibility was controlled by the Aegilops genemainly. All F1 plants showed high resistance to mixture stripe rust race, which is significant for disease resistance gene resources of wheat.