甘肃省冬小麦抗条锈菌CYR34育种策略

小麦条锈病是发生于甘肃省冬小麦生产上的最主要病害,种植抗病品种是防治该病最经济有效且有利于保护环境的措施。本文结合近年来甘肃省小麦条锈菌CYR34消长动态及致病性特点、冬小麦抗条锈育种研究现状与进展,提出了后CYR34时期抗病育种及抗病品种应用的思路,以期为持续控制甘肃省小麦条锈病、保障国家粮食安全生产提供技术支撑。

贵农系列小麦种质资源在甘肃陇南的抗条锈病研究

甘肃陇南是小麦条锈病的常发易变区,是条锈菌新小种的"策源地"。小麦条锈病是发生于该区域及甘肃省小麦生产上最主要的病害,种植抗病品种是防治该病最经济有效且绿色环保的措施。本研究对来自贵州大学的小麦种质资源材料贵农19、贵农21、贵农22、贵农29、贵农775在甘肃省农业科学院植物保护研究所兰州温室进行苗期人工接种鉴定,在甘谷试验站和天水市秦州区汪川良种场两地进行多年田间人工接种和自然诱发抗条锈病性鉴定及监测,结果发现:自2010年以来,由于以条锈菌CYR34为代表的贵农22致病类群的发生流行,使得贵农19、贵农21、贵农22在甘肃陇南田间先后丧失抗条锈病性而失去利用价值,贵农29、贵农775目前在甘肃陇南田间仍表现出较好的抗条锈病特性,特别是对条锈菌新菌系ZS-1表现免疫,是目前不可多得的小麦种质资源材料,可作为一线抗条锈病资源材料在陇南抗病育种中研究和利用。

Postulation of Seedlings Resistance Genes to Yellow Rust in Commercial Wheat Cultivars from Yunnan Province in China

The objective of this study was to characterize yellow （stripe） rust resistance gene（s） in 52 commercial wheat cultivars from Yunnan Province in China, and to provide information for their rational deployment in field. Seedlings of wheat cultivars were inoculated with 25 differential isolates ofPuccinia striiformis from foreign and home to postulate resistance genes to yellow rust, and then validated by pedigree. There were 10 probable resistance genes characterized in these cultivars, in which, Yr9 was most commonly postulated to be present in thirteen cultivars. Yr21, the second, was present in four cultivars. Yr8, the third, were present in three cultivars. Yr6, Yrl 7 and Yr26, the fourth, was present in two cultivars respectively. The other gene（s） such as, Yr2＋YrA, Yr7 and Yr27, were only present in single cultivar（s）; unknown gene（s） or gene（s） combination（s） were present in 22 cultivars. One cultivar （Yunmai 42） had no resistance gene tested in this study. Cultivars such as Yunmai 52, Mian 1971-98, Kunmai 4, and Yunmai 56 carried effective genes and can be popularized mainly; Yr9 should be planted with other Yr genes. In the meantime other effective genes should be introduced to realize gene diversity for controlling wheat yellow rust. Yunmai 42 should be reduced to avoid rust breakout. Unknown gene cultivars should be utilized and be researched deeply.

Molecular Mapping of Two Novel Stripe Rust Resistant Genes YrTp1 and YrTp2 in A-3 Derived from Triticum aestivum × Thinopyrum ponticum

Loss of variety resistance to stripe rust （Puccinia striiformis Westend f. sp.tritici） is an important factor causing massive periodical epidemic of rust in wheat production. Creation and development of new races of rust pathogen have led to serious crisis of resistance loss in widely planted varieties. This has quickened the search for new resistance resources. Molecular marker could facilitate the identification of the location of novel genes. A line A-3 with high resistance （immune） to currently epidemic yellow rust races （CY29, 31, 32） was screened out in offspring of Triticum aestivura x Thinopyrum ponticum. Segregation in F2 and BC1 populations indicated that the resistance was controlled by two independent genes： one dominant and one recessive. SSR markers were employed to map the two resistant genes in the F2 and BC1 populations. A marker WMC477-167bp located on 2BS was linked to the dominant gene with genetic distance of 0.4 cM. Another marker WMC364-2os bp located on 7BS was linked to the recessive-resistant gene with genetic distance of 5.8 cM. The two genes identified in this paper might be two novel stripe rust resistant genes, which were temporarily designated as YrTpl and YrTp2, respectively. The tightly linking markers facilitate transfer of the two resistant genes into the new varieties to control epidemic of yellow rust.

Population Genetic Analysis of Blumeria graminis f. sp. tritici in Qinghai Province, China

To gain more precise information about molecular genetic variation for wild populations of Blumeria graminis f. sp. tritici from Qinghai Province, China, 38 single-colony isolates were purified from samples collected from Haidong District, Xining City and Hainan Tibetan Autonomous Prefecture in 2010. The virulence of 21 isolates among them was tested at seedling stage on 34 wheat cultivars（lines） carrying known powdery mildew（Pm） resistant genes. The results showed that V1 a, V3 a, V3 c, V3 e, V5 a, V6, V7, V8 and V19 had high virulence frequencies（〉75%）, indicating a wide distribution; and V1 c, V5 b, V12, V13, V16, V21, VXBD, V2＋6, V2＋Mld and V4＋8, with less distribution, appeared to be lower in frequencies（0-20%）. The Nei＇s gene diversity（H）, Shannon＇s information index（I） and the percentage of polymorphic loci（P） were 0.23, 0.35 and 67.65%, respectively, which revealed a virulent diversity. The results from single nucleotide polymorphisms（SNPs） of 38 isolates showed that three housekeeping genes were found to contain a total of 9 SNP sites. 10 haplotypes（H1-H10） were inferred from the concatenated sequences, with 1 haplotype（H1） comprising of over 55% of Qinghai population. Phylogenic analysis did not show obvious geographical subdivision between the isolates. A multilocus haplotype network presented a radial structure, with H1 in the central as an inferred ancestor. Using analysis of molecular variance（AMOVA）, we found 1.63% of the total variation was among populations and 98.37% within populations, with a low fixations index（FST=0.01634, P〈0.05）. This revealed a relatively high genetic diversity but a low genetic divergence in Qinghai population. Moreover, the molecular data on gene flow（Nm=6.32） confirmed the migration of pathogen populations among areas in Qinghai Province.

我国甘肃和青海地区麦蚜田间种群对5种杀虫剂的抗性监测

[目的]研究明确甘肃和青海省麦蚜田间种群的抗性水平。[方法]用玻璃管药膜法测定5种杀虫剂对麦蚜的杀虫活性。[结果]采自甘肃省清水县、临夏县、文县的3个禾谷缢管蚜种群对吡虫啉、啶虫脒、抗蚜威、高效氯氰菊酯、氧乐果的抗性倍数介于0.54~1.92倍,均小于2倍,仍处于敏感状态。在采自甘肃省甘谷县、金昌市、民乐县、青海省湟中县的4个麦长管蚜种群中,仅青海省湟中县的麦长管蚜种群对抗蚜威的抗性倍数为3.3倍,处于敏感性下降水平,其余种群对5种杀虫剂的抗性倍数为0.18~2.83倍,均小于3倍,处于敏感水平。[结论]甘肃省和青海省一些地区的麦蚜种群对5种杀虫剂处于敏感状态,这5种杀虫剂可用于这些麦蚜防治。