小麦-华山新麦草抗全蚀病新种质的分子细胞遗传学研究

Studies on molecular cytogenetics of wheat-Psathyrostachys huashanica germplasm with resistance to wheat take-all fungus

对小麦-华山新麦草附加系H20和代换系H1的抗病性及分子细胞遗传学进行了研究。结果表明,H20和H1的体细胞染色体数目范围分别为42～44和40～42,2n=44和2n=42的细胞频率分别为58.33%和90%;花粉母细胞减数分裂中期 ,染色体构型分别为21.55 +0.90 和20.74 +0.52 ,22 和21 的细胞频率分别为61.56%和86.18%;与中国春测交,21 +1 和20 +2 的细胞频率分别为70.14%和88.59%。用华山新麦草基因组DNA作探针进行原位杂交,结果显示H20和H1中均有2条华山新麦草染色体,他们的染色体构成分别为2n=44=42W+2N和2n=42=40W+2N。对全蚀病菌,H20表现近高度抗病性,H1表现中度抗病性。

The molecular cytogenetics and disease resistance of addition line H20 and substitution line H1 from wheat-P.huashanica (2n=14,NN) were studied.The results showed that the somatic chromosome numbers were 42 to 44 from H20 and 40 to 42 from H1,and the cells rates of 2n=44 and 2n=42 were \{58.33%\} and 90% respectively.The chromosome configurations were 21.55Ⅱ+0.90 I from H20 and 21Ⅱ+0.52Ⅰ from H1,the cells of 22Ⅱand 21Ⅱ were accounted for 61.56% and 86.18% respectively and after test crossed with CS,the percentages of 21Ⅱ+1Ⅰand 20Ⅱ+2Ⅰwere 70.14% and 88.59% respectively in PMC at MI.The in situ hybridization using P.huashanica genomic DNA as probe showed that H20 and H1 possessed 2 chromosomes of P.huashanica and their chromosome constitutions could be expressed as:2n=44=42w+2N and 2n=42=40W+2N respectively.H20 behaved close to high resistance and H1 showed middle resistance to wheat take-all fungus.