采用常规分离法对不同生长季节苹果树的不同部位进行了内生细菌分离.结果表明,内生细菌的分离几率和数量不同.通过平板对峙培养和发酵液抑菌活性测定,在所分离的118个菌株中,筛选出7株对苹果斑点落叶病菌(Alternaria alternata f. sp. Mali)具有较强拮抗作用的菌株,其中菌株B86和B91的发酵滤液在活体上对苹果斑点落叶病的防治效果显著,分别为73.72%和75.32%.两菌株培养滤液对病菌分生孢子萌发具有抑制作用,并造成芽管畸形膨大,呈泡囊状,泡囊消解破裂;两菌株产生的抑菌物质具有热稳定性.表明B86和B91菌株具有一定的生防潜力.
M8657-1,one of the wheat translocation lines derived from Leymus mollis Trin.Hara,is possessed of effective resistance at all stages to Su-11 and other dominant races of Puccinia striiformis f.sp.tritici in China.Seedlings of the parents,F1,and F2 progeny derived from the cross of M8657-1(resistant)Ming-xian169(susceptible)were inoculated with Su-11 in greenhouse to identify and map the probable new stripe rust resistance gene.The results suggested that the stripe rust resistance in M8657-1 was conferred by a pair of recessive genes.Simple sequence repeat(SSR)technique was used to detect molecular marker associated with the resistance gene:208 pairs of wheat SSR primers were used to screen the two parents,as well as resistant and susceptible bulks and then three SSR markers were selected for genotyping the F2 population.The gene,temporarily designated as YrLm1,was found to be located on the chromosome 7DL and flanked by three SSR markers GDM67,WMC150 and WMC671,with the genetic distance of 5.0,9.7 and 11.8cM,respectively.
