70℃干热处理德兰臭草种子内生真菌的研究

为了更好地研究内生真菌与德兰臭草(Melica transsilvanica)的互作关系,需获得内生真菌种群已失活的德兰臭草种子。本试验采用70℃干热的方法对德兰臭草带菌种子分别处理5d,10d,15d,20d,25d和30d,以不作处理的种子为对照,通过测定各处理后种子的萌发指标、生长指标和植株内生真菌数量等综合评价内生真菌的灭活效果。结果表明,70℃干热处理能有效杀灭德兰臭草种子中的内生真菌;70℃处理5d后,与对照相比,宿主染菌率下降为50%;处理25d时,种子和植株中均未分离出内生真菌。同时,70℃处理25d时,种子发芽率、发芽势、发芽指数、植株鲜重和胚根、胚芽长度以及植株株高、叶片数、分蘖数、叶宽和茎粗与对照相比均没有显著影响。值得一提的是,70℃干热处理种子可促进植株须根数的增多和根长的增加。综合比较得出,70°C干热处理25d能使德兰臭草种子中全部内生真菌失活,是一种简单、方便、可行的方法。

Using 70℃ Dry Treatment to Make Endophyte-free Seeds of Melica transsilvanica

In this study a dry-heat treatment was used to make endophyte-free populations of Melica transsilvanica.The elimination effects of the seed containing endophyte were tested by treatment at 70℃ for 5 d,10 d,15 d,20 d,25 d and 30 d,and the seeds not treated were used as control.The result showed that at 70℃ for 25 d was effective in killing the endophyte in the seeds.The endophyte was very sensitive to the dry-heat treatment,the endophyte infection rate was reduced to 50％ after 5 d treatment,and the endophyte infection rate was reduced to 0 after 25 d treatment.At the same time,there are no obvious differenrces in the seeds germination rate and plant growing indexes.Intriguingly,70℃ dry treatment can promoting root number and root length.Therefore,70℃ for 25 d treatment was an simple,convenient and feasible way to make endophyte-free M.transsilvanica germplasm.