139份大麦种质材料苗期和成株期抗白粉病鉴定评价

为给培育大麦持续性抗白粉病品种提供有价值的抗源,利用7个大麦白粉病菌优势小种,在实验室条件下分别接种139份大麦品种(系),进行苗期抗性鉴定,同时于2009-2011年度在云南保山对参试品种(系)进行田间成株期抗性鉴定,并考查成株期抗病材料的农艺性状.结果表明,参试品种(系)在苗期对7个优势小种表现出48个不同的抗性反应谱,13个大麦品种(系)能抗所有参试的优势小种,22个大麦品种(系)能抗4～6个优势小种.25个大麦品种(系)具有成株期抗病性.大麦苗期抗性与成株期抗性并不完全一致,但苗期抗优势小种数较多的材料中,成株期表现抗性的也较多,5个苗期抗所有优势小种的大麦品种(系)均表现出成株期抗性.25个成株期抗病品种(系)中18个为二棱皮大麦,7个为多棱裸大麦,它们株高、穗长、穗粒数扣千粒重的变异系数较大,二棱皮大麦株高、穗长、穗粒数和千粒重的变异系数分别为10.3％、15.0％、12.0％和20.6％,多棱裸大麦分别为18.3％、26.4％、19.5％和22.8％.

Identification of Resistance to Powdery Mildew of 139 Barley Varieties (lines) at Adult and Seedling Stages

Barley powdery mildew caused by Blumeria graminis. f.sp. hordei is one of the most destructive foliar diseases of barley in China.The disease can reduce barley grain yield by 20% to 30%. Breeding for genetic resistance is an economically and environmentally sustainable way to control powdery mildew. Adult plant resistance is expressed at later stages of plant growth and is durable,and is used for breeding barley cultivars with durability against powdery mildew. Screening of resistance barley germplasm to powdery mildew is prerequisite for an efficient use of available resistance genes. In the study,the resistance at seedling stage to powdery mildew in 139 barley varieties (lines) were identified by inoculating 7 isolates of predominant B. graminis. f.sp. hordei physiological races onto them in a climate room,and the resistance at adult stage to powdery mildew in them were identified by natural field inoculation in Baoshan in a successive two years of 2009-2011.The results indicated that 48 different infection response spectrums were found when 7 isolates of dominant races were inoculated onto 139 barley varieties (lines) at seedling stage,13 of 139 barley ones were resistant to all isolates tested and 22 of them were resistant to 4 to 6 of the used dominant race isolates. 25 of all the barley varieties (lines) determined were resistant at adult stage,the ones susceptible at seedling stage in them were possibly resistant at adult stage,and vice versa,but more resistant ones were detected in those ones which were resistant to most of all the dominant races at seeding stage,and 5 barley varieties (lines) resistant to all the dominant races at seedling stage were resistant to the disease at adult stage.Large variation coefficients were found among their plant height,spike lengths,spike grain number and kilo-grain weightiness.Of 25 barley varieties (lines) resistant at adult stage,18 were two-rowed and 7 were poly-rowed and hulless. The variation coefficients of plant height,spike length,spike grain number and kilo-grain weightiness in the two-rowed and hull barley population were 10.3%,15.0%,12.0% and 20.6%,respectively,and those in poly-rowed and hulless barley population were 18.3%,26.4%,19.5% and 22.8%,respectively.