보리 붉은곰팡이병 검정법과 저항성 품종 선발

Establishment of Artificial Screening Methods and Evaluation of Barley Germplasms for Resistance to Fusarium Head Blight

이 실험은 보리의 붉은곰팡이병에 대한 정밀하고 효율성이 높은 검정체계를 확립하고, 이를 토대로 저항성 품종을 선발하고자 실시하였다. 이를 위해서 온·습도 조절이 가능한 붉은곰팡이병 전용 습실 검정상을 제작하여 포트 재배한 식물체에 3개의 다른 접종시기별(출수기, 출수후 3일, 출수후 5일)로 SCK-O4균주의 분생포자 현탁액 5.0×105 macroconidia mL-1를 각각 접종하고 4개의 다른 기간 동안 습실처리(1, 3, 5, 7일)를 하여 각 처리별 이병 정도를 평가하였다. 또한 절단이 삭검정법을 통한 대량검정법도 검토하였다.1. 습실 검정상 내에서의 붉은곰팡이병 발병률은 접종시기에 따라 차이를 보이지 않았으나, 습실처리기간에 따라서는 유의한 차이를 보였다.2. 습실 검정상을 이용한 붉은곰팡이병의 저항성 검정은 출수기에 접종하고 습실 검정상 내에서 7일간 유지하여 판정하는 것이 가장 효율적이었다.3. 포트검정법과 절단이삭검정법의 검정방법간 발병 정도는 고도로 유의한 정의 상관(r=0.892**)을 보였다.4. 저항성 품종은 진광보리, 부흥, Atahualpha92, Chevronb,Gobernadora-d 및 MNBrite-c 등이 선발되었으며, 이들 품종은 2개의 검정시기에서 일정한 저항성을 나타내었다.

Fusarium head blight (FHB) is a severedisease problem that affects the quality and yield of barleygrain. The evaluation of FHB resistance is difficult becauseenvironmental conditions greatly influence FHB infectionestablish an efficient screening method for selectingresistant barley to FHB, 2) compare FHB severity betwenthe cut-spike method and pot-plant method for developmentof mass screening, and 3) estimate FHB resistance forbarley germplasms. Barley cultivars and lines wereevaluated for reaction to FHB in controlled-grenhousecondition. Spikes were spray-inoculated with a suspension(5.0× 105 macroconidia mL-1) of Fusarium graminearumSCK-O4 strain, and then kept in a grenhouse at 18-25oCwith 80-100% relative humidity. Inoculation were employedat 3 different heading growth stages (heading date, thredays after heading, and five days after heading). Theinoculation was performed in 2 consecutive days in order togrenhouse at 4 different free moisture periods (1, 3, 5, and7 days). The percentage of FHB severity was scored from 0to 9 according to the rate of infected kernels per spike, andthre spikes were evaluated per replication with 3 replicates.There were significant differences of FHB severitydepending on the diferent fre moisture periods, but not bythe inoculation at different heading stages. The optimumevaluation point of FHB severity in the grenhousecondition was on the 7th day under fre moisture conditionafter inoculation at the heading date. Infection level in cut-spike method highly correlated with that in pot-plantmethod. This suggested that cut-spike method is useful inevaluating of FHB resistance in barley. Six cultivars, such asGobernadora-d, and MNBrite-c, were selected as resistantvarieties to FHB. Corelation coefficient for the FHBseverity evaluated by the pot-plant method between twoseasons was 0.794, indicating the stability and accuracy ofthe screning method.