白头翁菌核病发生危害调查及其病原菌生物学特性

为明确辽宁省白头翁菌核病发生危害情况及其病原菌生物学特性,于2011—2013年对该省3个白头翁种植基地进行菌核病调查,并采用平板培养法和离体接种法对白头翁菌核病菌Sclerotinia nivalis Saito进行生物学特性研究和致病性测定。结果表明,白头翁菌核病在各种植基地发生程度不一,抚顺市白头翁发病较重,2013年一般地块病株率为0~37.1%,重者达60.4%,本溪市和沈阳市发病相对较轻,病株率分别为1.3%~10.0%和0~3.0%;随着白头翁栽培年限的增加,菌核病危害逐渐加重,1~4年生白头翁的病株率分别为0、12.3%、37.1%和60.4%;坡地沿山体横垄栽植较纵垄栽植发病重。白头翁菌核病菌在PDA培养基上生长最好,菌丝生长速度和菌核形成数分别为10.4 mm/d和101.0个/皿;菌丝生长和菌核形成的最适温度分别为20℃和15℃,最适pH均为6;连续光照和连续黑暗利于菌丝生长,光照条件下菌核形成最多;碳、氮源对菌丝生长和菌核形成的影响较大,菌丝生长最适碳源为果糖、葡萄糖和蔗糖,以尿素作氮源抑制该菌生长。伤口有利于该病的发生发展,刺伤接种较未刺伤接种发病早,接种3 d后开始发病,6 d后即达高峰期。

Occurrence of sclerotinia rot of Pulsatilla koreana and biological characteristics of Sclerotinia nivalis

In order to investigate the occurrence of sclerotinia rot of Pulsatilla koreana in Liaoning Province and its pathogenic biological characteristics,the surveys of disease were conducted from 2011 to 2013 in three major production fields in Liaoning Province,and the biological characteristics and pathogenicity were tested by using plating method and vitro inoculation.The results showed that the disease occurred differently,in which it was more serious in Fushun City,with the disease incidence of 0-37.1％ generally and 60.4％ seriously in 2013.The disease incidence of Benxi and Shenyang cities were lighter,with the incidence of 1.3％-10.0％ and 0-3.0％,respectively.With the plant growth longer,the disease became more serious,and the disease incidences from one to four year old plants were 0,12.3％,37.1％ and 60.4％,respectively.The incidence of cross ridge ranging the mountain was more serious than that of lengthways.The optimum medium was PDA with the growth rate and number of sclerotia of 10.4 mrn/d and 101.0 in per dish,respectively.The optimum temperature for mycelial growth and sclerotial formation were 20℃ and 15 ℃,respectively.The optimum pH was 6.Continuous light and dark were beneficial to mycelial growth,and continuous light were beneficial to sclerotial formation.Mycelial growth and sclerotial formation with the influences of carbon and nitrogen sources were significantly different,the optimum carbons were the fructopyranose,glucose and sucrose,and urea could inhibit the fungus growth.Wounding enhanced disease severity.It's earlier of wounded inoculation with a three days occurrence and the highest was in six days than that of unwounded.