珊瑚菜柄锈菌性孢子阶段的发现及北沙参锈病研究简报

 北沙参(植物名珊瑚菜Glehnia littoralis)为名贵药材,锈病是北沙参的重要病害,其病原为珊瑚菜柄锈菌Puccinia phellopteri Syd.。该菌虽早有记述,但迄今只见有冬、夏孢子阶段的报道,对其生活史及侵染循环尚不清楚。     

玉米南方型锈病发生规律与防治技术初步研究

采用田间调查和试验的方法,着重研究了玉米南方型锈病病菌多堆柄锈菌夏孢子发芽与环境条件的关系,玉米不同生育期的感病性和病害的初侵染来源,并探讨了控制该病为害的主要技术途径。     

小驳骨锈病的发生与防治研究初报

1999年在南宁市郊发现由柄锈菌 (Puccinia sp)引起的小驳骨锈病 ,发病程度逐年加重 ,传播范围逐渐扩大。病菌冬孢子在 RH10 0 % +水滴条件下 (2 5℃ )易萌发 ,病害盛发期为春末夏初及秋末冬初。用修剪清除病枝叶、清除病枝叶并结合施肥管理、 0 .5°Be石硫合剂、 30 0 0倍 2 0 %粉锈宁乳油 4种方法进行防治试验 ,防治效果分别为 10 0 %、 10 0 %、 5 1.6 %、6 4 .5 % ,以第 2种防治方法效果最佳     

玉米南方锈病发生温度范围测定

玉米南方锈病由玉米多堆柄锈菌(Puccinia polysora Underw.)引起,主要分布在热带和亚热带地区,但随着全球气候变暖,其发生范围不断扩大,对玉米生产的影响也随之扩大。对于该病害发病温度范围的测定有助于病害发生范围的区划和病害预防工作的进行。试验将多堆柄锈菌接种到供试玉米材料‘郑单958’上,置于不同温度下的光照培养箱中培养并观察发病情况,从而确定出玉米南方锈病的发病温度范围以及发病最适温度范围。试验结果表明:玉米南方锈病的发病温度范围为15~31℃,最适温度范围为24~27℃。     

大蒜锈病的发生和防治

大蒜是人们喜爱的蔬菜之一,在神农架林区农村家家都有种植,但近几年大蒜锈病发生呈加重趋势,成为我区大蒜主要病害,发病率在80%以上,发病面积在200 hm2以上,感病大蒜蒜头小,易开裂,严重影响大蒜的产量和质量,农民强烈要求对其进行及时控制,为了科学地对我区大蒜锈病进行防治,笔     

荷兰豆锈病的发生与防治

荷兰豆是近几年来农村普遍栽培的菜用豆类之一 ,它既增加农民的收入 ,又丰富了城乡居民的物质生活。但是荷兰豆锈病却是影响荷兰豆生长的主要病害之一 ,病株叶片早衰早落 ,豆荚的食用价值大减 ,严重时减产可达 5 0 %以上 ,因此 ,认真对待是十分必要的。1　病害特征　　主要危害叶片 ,影响光合作用 ,严重时叶柄和豆荚也受害 ,病斑初期常出现黄白色小点 ,随而变成红褐色 ,隆起呈小疮疱斑 ,外围常有黄色晕环。有时老病斑四周有一圈新的红褐色疱状物 (病源菌的夏孢子堆 ) ,表皮破裂后散发出红褐色粉末 ,病株茎叶上有园形褐色小斑点。后期叶片 ,…     

夏谷锈病的发生与防治

夏谷锈病的发生与防治贺献林（河北省涉县农业局植保站０５６４００）谷子锈病是近几年夏谷的一种主要病害。在邯郸市各地均有发生，而山区发生尤为严重，一般年份病株率１５～４０％，重发时病株率达１００％，产量损失１２～２０％，甚至更高，我们自１９９２年开始对其...     

玉米锈病的研究进展

文章对玉米锈病的病原菌类型和症状作了详细描述 ,介绍了该病在我国近年的发生危害情况 ,并提出防治对策     

辽宁省发生穿山龙锈病

穿山龙(Dioscorea nipponica Makino)又名穿龙薯蓣、穿地龙等, 为薯蓣科, 薯蓣属缠绕藤本药用植物, 主产于我国东北及华北地区[1].其根茎入药, 具有舒筋活血, 消食利水, 祛风止痛功效.有效成份皂素是止痛药、避孕药和甾体激素类药物的重要原料.长期以来我国穿山龙主要源于野生, 由于国内外合成甾体激素类药物迅猛发展, 穿山龙需求量迅速增长, 近年来辽宁东部山区为了发挥野生资源优势, 开始大面积人工栽培穿山龙.在人工栽培条件下, 穿山龙锈病发生危害严重.      

四川地区小麦叶、秆锈菌的越冬和越夏

小麦叶锈病是四川冬、春麦上的常发病害,但仅在局部地区偶尔流行;叶锈菌在盆地内以夏孢子越冬,仅很少夏孢子能越夏,其主要越夏场所在海拔800～3 500 m地区的各类小麦上,而在1 900 m海拔地区、6～8月均温19.5℃的地方越夏菌量最大,呈显著优势。小麦秆锈病则是春麦区偶然流行的病害,其在盆地内常年无越冬菌源,但可在盆地内直至3 500 m海拔地区的小麦上越夏,其中以1 500 m以下,特别是700 m左右,6～8月均温23℃的地方越夏菌量较大。     

Susceptibility in oats to stem rust induced by co-infection with leaf rust

Induction of susceptibility in oats to a normally avirulent pathotype of Puccinia graminis f.sp. avenae was studied in the presence of different pathotypes of P. coronata f.sp. avenae . Induction occurred on seedlings only in the presence of a virulent culture of P. coronata avenae and was not dependent on time or order of inoculation of either pathogen. This phenomenon was restricted to seedlings of lines possessing the Pg-a source of oat stem rust resistance. The specificity of induced susceptibility can be used as a valuable bioassay for screening and identifying Pg-a . Induced susceptibility occurred only at the seedling stage, and apparently provides no obstacle to the use of Pg-a as a source of stem rust resistance in oats.     

芍药病害的发生及其综合防治

根据调查结果：在江西芍药生长过程中常发生5种病害，对其病原、症状进行了描述，并调查了发病规律，在防治方法上提出综合防治，多从改善生态环境与药剂相结合，达到控制病害发生与为害。     

Virulence associations in oat crown rust

ABSTRACT Isolates of Puccinia coronata obtained from natural populations of Avena sterilis in Israel, winter oat (A. sativa) cultivars in Texas, and spring oat cultivars in the Northern Plains states of Minnesota, North Dakota, and South Dakota were analyzed for significance of pairwise virulence associations. Isolates from all three regions were tested on 25 oat lines with single P. coronata (Pc) genes for crown rust resistance from A. sterilis and one line with a Pc gene from A. sativa. Isolates from Israel were tested also on 11 Iowa backcross lines with undesignated crown rust resistance genes from A. sterilis. Four associated virulence groups were identified from significant positive virulence associations that were consistent across all three regions. Group 38 included virulence to Pc-38, Pc-39, Pc-55, Pc-63, and Pc-71; group 45 included virulence to Pc-45, Pc-46, Pc-48, Pc-52, Pc-54, and Pc-57; group 58 included virulence to Pc-35, Pc-40, Pc-58, and Pc-59; and group 61 included virulence to Pc- 36, Pc-51, Pc-56, Pc-60, and Pc-61. Virulence to Pc-70 showed the strongest association to virulences in group 38 but also showed significant association with virulence to Pc-45, Pc-35, and Pc-58. Virulences in group 61 were consistently negatively associated with virulences in group 38 in each region. In Israel, virulences to five of the Iowa lines showed positive associations to virulences in group 61 and negative associations to virulences in groups 38 and 45. Close similarity of reactions of nearly all isolates to Pc-39, Pc-55, and Pc-71 suggest that these genes may be identical or nearly identical alleles.     

Inheritance of rust resistance in Macroptilium atropurpureum

Sixteen accessions of Macroptilium atropurpureum showed a range of reaction types when seedlings were inoculated with a single-urediniospore isolate of Uromyces appendiculatus (rust). Analysis of F₂ families of crosses with the susceptible cv. Siratro showed that in seven accessions resistance was dominant, regulated by a single locus in four of these but by more than one locus in the three others. At least three of these loci were identified as non-allelic. In one accession resistance was near-recessive and regulated at a single locus, while combinations of dominant and recessive alleles at different loci explained the segregation of resistance in other accessions. Loci with partial dominance and expressivity varying with environment were also observed. There was some evidence that the expression of resistance could be temperature sensitive and that the fungus exhibited differential virulence.     

电场对白沙蒿和沙蒿瘦果粘液粘附功能的影响

用不同强度的电场处理沙生植物白沙蒿(Artemisiasphaerocephala)和沙蒿(Artemisiaarenaria)果实,在自然环境下研究电场作用后粘液物质将沙粒粘附于瘦果周围后瘦果重量的变化情况、果实水合与脱水情况、粘液果实及剔除粘液层的果实萌发情况。结果表明:适宜的电场使粘液瘦果吸附沙粒多,果实吸水快,脱水慢,粘液果实发芽率高于对照组,而电场对剔除粘液层果实发芽率无影响。     

Mapping of Aegilops umbellulata‐derived leaf rust and stripe rust resistance loci in wheat

Aegilops umbellulata, a non‐progenitor diploid species, is an excellent source of resistance to various wheat diseases. Leaf rust and stripe rust resistance genes from A. umbellulata were transferred to the susceptible wheat cultivar WL711 through induced homoeologous pairing. A doubly resistant introgression line IL 393‐4 was crossed with wheat cultivar PBW343 to develop a mapping population. Tests on BC₂F₇ RILs indicated monogenic inheritance of seedling leaf rust and stripe rust resistance in IL 393‐4 and the respective co‐segregating genes were tentatively named LrUmb and YrUmb. Bulked segregant analysis placed LrUmb and YrUmb in chromosome 5DS, 7.6 cM distal to gwm190. Aegilops geniculata‐derived and completely linked leaf rust and stripe rust resistance genes Lr57 and Yr40 were previously located in chromosome 5DS. STS marker Lr57/Yr40MAS‐CAPS16 (Lr57/Yr40‐CAPS16), linked with Lr57/Yr40 (T756) also co‐segregated with LrUmb/YrUmb. Seedling infection types differentiated LrUmb from Lr57. Absence of leaf rust‐susceptible segregants among F₃ families of the intercross (IL 393‐4/T756) indicated repulsion linkage between LrUmb and Lr57. YrUmb expressed a consistently low seedling response under greenhouse conditions, whereas Yr40 expressed a higher seedling response. Based on the origin of LrUmb/YrUmb from the U genome and Lr57/Yr40 from the M genome, as well as phenotypic differences, LrUmb and YrUmb were formally named Lr76 and Yr70, respectively. These genes have been transferred to Indian wheat cultivars PBW343 and PBW550, and advanced breeding lines are being tested in state and national trials.     

Genetics of resistance to wheat leaf rust, stem rust, and powdery mildew in Aegilops sharonensis

Aegilops sharonensis (Sharon goatgrass) is a wild relative of wheat and a rich source of genetic diversity for disease resistance. The objectives of this study were to determine the genetic basis of leaf rust, stem rust, and powdery mildew resistance in A. sharonensis and also the allelic relationships between genes controlling resistance to each disease. Progeny from crosses between resistant and susceptible accessions were evaluated for their disease reaction at the seedling and/or adult plant stage to determine the number and action of genes conferring resistance. Two different genes conferring resistance to leaf rust races THBJ and BBBB were identified in accessions 1644 and 603. For stem rust, the same single gene was found to confer resistance to race TTTT in accessions 1644 and 2229. Resistance to stem rust race TPMK was conferred by two genes in accessions 1644 and 603. A contingency test revealed no association between genes conferring resistance to leaf rust race THBJ and stem rust race TTTT or between genes conferring resistance to stem rust race TTTT and powdery mildew isolate UM06-01, indicating that the respective resistance genes are not linked. Three accessions (1644, 2229, and 1193) were found to carry a single gene for resistance to powdery mildew. Allelism tests revealed that the resistance gene in accession 1644 is different from the respective single genes present in either 2229 or 1193. The simple inheritance of leaf rust, stem rust, and powdery mildew resistance in A. sharonensis should simplify the transfer of resistance to wheat in wide crosses.     

Occurrence of oat stem rust in west Wales

The first significant occurrence of stem rust ( Puccinia graminis Pers, ssp, graminis var, stakmanii Guyot, Massenot & Saccas ex, Urban) on spring oats ( Avena sativa L.) in west Wales, UK is reported.