北沙参锈病病原、发病规律及综合防治方法研究

研究明确了北沙参锈病病原是一种缺锈孢型的、单主寄生锈菌;病菌以冬孢子在田间病残体上越冬,夏孢子不断侵染导致锈病流行;通过室内和田间药剂筛选,明确了多菌灵和代森锌是防治北沙参锈病的有效药剂,粉锈宁对北沙参锈病无效;防治北沙参锈病应采取农业防治与化学防治相结合的综合防治技术。     

新疆灌木锈菌的分类鉴定

通过光学显微镜和扫描电子显微镜对采自新疆荒漠植被的62份灌木锈菌标本进行分类鉴定.共鉴定出灌木锈菌17个种,其中Phragmidium有10个种,Uromyces 5个种,Puccinia 2个种,Phragmidium,andersonnii Sheat和Puccina longirostris Kom为中国新纪录种.     

Distinguishing nitrogen deficiency and fungal infection of winter wheat by laser-induced fluorescence

One of the most important tasks in precision farming is the site-specific application of fertilisers and pesticides in heterogeneous large-area fields. For such site-specific crop management, effective remote sensing methods for the detection of crop diseases and nutrient deficiencies are required. The aim of the present work was to compare laser-induced fluorescence (LIF) parameters from nitrogen-deficient and pathogen (rust and mildew)-infected winter wheat (Triticum aestivum L.) plants and to assess the potential of LIF to detect and discriminate between these types of stress. Both long term nitrogen deficiency and pathogen infection resulted in an increase of the ratio of fluorescence at 686 and 740 nm (F686/F740) accompanied by a reduction of leaf chlorophyll content to approximately 35 μg cm⁻². A linear negative correlation between chlorophyll content and F686/F740 ratio (r² = 0.78) was found for leaves with chlorophyll content ranging between 17 and 52 μg cm⁻². Since chlorophyll breakdown appeared an unspecific symptom to both nitrogen deficiency and pathogen infection, it was not possible to discriminate between these types of stress only by means of the F686/F740 ratio. Specific for the pathogen-infected leaves was a large heterogeneity in the records of their spectral parameters caused by inhomogeneous, discrete lesions of fungi infection. Nitrogen-deficient plants with homogeneous reduction in chlorophyll content showed, in contrast, more uniform readings of the spectral parameters. Thus, mildew- and rust-infected plants, grown under sufficient nitrogen fertilisation could be distinguished from those grown under reduced nitrogen supply by the higher variance of their spectral readings. The simultaneous scanning multipoint mode measurements of LIF and laser light reflection characteristics with parallel estimation of their heterogeneity is proposed for the discrimination between nitrogen deficiency and pathogen infection under field conditions.     

细叶结缕草锈病的研究

细叶结缕草锈病（Puccinia zoysiae Diet）是细叶结缕草的主要病害。据 1994年观察,越冬前未经修剪的草坪或漏剪的草丛春天发病早而重,可见此病发生与病菌越冬有密切关系。室内人工接种18～28℃之间病害潜育期为7～9天,30～35℃时不发病。夏孢子萌发适温为25℃,30℃以上萌发率迅速下降,致死温度为44℃,可见夏季病情下降与高温有关。1994年病害发生高峰期在5～7月。     

吉林省玉米锈病发病规律若干问题的研究

对吉林省玉米锈病发生规律的若干问题进行了研究,明确了以下问题:玉米植株在生育后期对锈菌的侵染抵抗能力要明显强于生育前期;玉米不同叶位的叶片抗侵染能力有明显差异,老叶抗病性强于新叶;增施N肥和P肥,可削弱玉米对锈病的抵抗能力,但增施K肥可增强玉米对锈病的抵抗能力;玉米品种对锈病的抗性差异显著,自交系2L637、2L725、单交种铁15、辽单33、丹玉3、铁12抗性较好。     

Faba bean breeding for disease resistance

Faba bean is a major grain legume widely cultivated in many countries for food and feed purposes. A number of aerial fungi, together with soil-borne pathogens associated with foot and root rot complexes, nematodes, parasitic weeds and viruses may cause severe diseases in faba bean crops. The use of genetic resistance is the most economical and environmentally friendly control method. However, to date no efficient sources of resistance have been described to some diseases, or it is scarce and of complex nature, making necessary the implementation of other control measures. Phenotypic expression of resistance is usually poorly described. As a consequence of this, and of the poorly developed genomic resources available, the genetic basis of resistances is, in most cases, largely unknown. Effectiveness of MAS might soon increase with the adoption of new improvements in marker technology together with the integration of comparative mapping and functional genomics. In this paper we will review and critically discuss current and future strategies on breeding faba bean for disease resistance.     

一个大豆锈病新抗源的筛选与鉴定

采用离体叶片接种方法对2007-2010年收集的1 000份大豆种质资源进行抗性筛选,得到1份高抗材料SX6907。SX6907在接种后20d不产生侵染病斑;在高浓度锈菌接种时,产生少数红褐色RB（Red-brown）病斑,但无孢子堆破裂现象,无孢子产生;SX6907的接种表现与已知抗病品种主要表现为黄褐色TAN型感病病斑明显不同。组织学观察表明, SX6907在接种部位造成细胞坏死,侵染点无孢子形成,其抗性表现为抗锈菌侵染。SX6907是一个优异的抗锈病资源,可做亲本在抗锈病育种中应用。     

葱蒜锈病叶的红外光谱研究

[目的]采用傅里叶变换红外光谱对葱蒜锈病叶进行了研究,探讨中红外光谱在作物病害诊断中的应用潜力。[方法]用傅里叶变换红外光谱测试了葱蒜正常绿叶及锈病叶,分析其光谱差异。[结果]葱、蒜绿叶的红外光谱主要显示了多糖类物质、蛋白质、酯类振动;正常绿葱蒜叶和锈病葱蒜叶光谱在1 800～1 000 cm-1指纹范围显示了差异,与正常绿叶相比,锈病葱叶在1 640 cm-1的酰胺Ⅰ振动峰变强,在1 103 cm-1处的肩峰不明显;锈病叶的吸收强度比A1640/A1063、A1640/A1736、A1640/A2924和A1063/A2924较正常叶相应比值A1638/A1059、A1 638/A1 738、A1 638/A2 922和A1 059/A2 922变大。正常蒜叶的多糖振动峰1 056 cm-1为指纹区的最强峰,而锈病叶在1 634 cm-1处峰为指纹区的最强峰;锈病蒜叶的吸收强度比A1634/A1069、A1634/A1099、A1409/A2923和A1634/A1737较正常叶的相应比值A1627/A1056、A1627/A1104、A1411/A2920和A1 627/A1 740变大,锈病叶的A1 634/A2 923、A1 069/A2 923和A1 737/A2 923较相应正常叶的A1 627/A2 920,A1 056/A2 920,A1 740/A2 920变小。[结论]根据红外光谱差异可以区分绣病叶与正常叶,红外光谱可望发展成为作物病害检测的方法。     

250g/L丙环唑EC防治小麦条锈病和白粉病的效果探讨

为探明250 g/L丙环唑EC对小麦条锈病和白粉病的防治效果及合理使用剂量,采用测报调查、随机区组设计和统计分析方法,开展了250 g/L丙环唑EC防治小麦条锈病和白粉病田间药效试验示范。结果表明,在春季条锈病流行期间,用250 g/L丙环唑EC 600 m L/hm2、450 m L/hm2和300 m L/hm2连续施用2次,对小麦条锈病有很好的防治效果,药后8天和18天防效均在98%以上,且各使用剂量之间防效差异不显著。对小麦白粉病亦有很好的防治效果,药后8天防效均达100%,但持效期仅10天左右,药后18天,防效显著下降,用250 g/L丙环唑EC 600 m L/hm2防治效果仅78.4%,用250 g/L丙环唑EC 450 m L/hm2及以下剂量,防治效果在41%以下。在小麦条锈病和白粉病发生不重情况下,使用最佳剂量为300~450 m L/hm2,有利于减少农药使用量和农残污染,节约防治成本。但在白粉病偏重及以上发生和条锈病混发麦地,须连续2次用250 g/L丙环唑EC 600 m L/hm2,以确保防治效果。利尔化学股份有限公司和先正达苏州作物保护有限公司生产的250 g/L丙环唑EC,用量相同防效没有差异,且国内和国外公司生产的250 g/L丙环唑EC质量没有差异。从节约防治成本考虑,最好用国内利尔化学股份有限公司生产的250 g/L丙环唑EC。     

盐碱土锈腐病拮抗菌的筛选和鉴定

[目的]对黑龙江省大庆地区盐碱土壤进行嗜(耐)盐碱菌的筛选。[方法]采用不同Na Cl浓度梯度的Sehgal-Gibbons平板筛选,利用琼脂块法获得对人参锈腐病病原菌有拮抗作用的嗜(耐)盐碱菌株,并将传统的形态学观察与现代分子生物学技术相结合对其进行鉴定。[结果]从大庆地区盐碱土壤中共分离出48株细菌,其中60.4%的菌株为耐盐菌,其余为中度嗜盐菌。所有菌株的耐碱能力在pH 8.0~11.0,其中64.6%的菌株耐碱能力高达pH 11.0,除2株为嗜碱菌,其余均为耐碱菌。人参锈腐病毁灭柱孢菌R2拮抗性筛选获得3株菌,经形态学、生理生化特征及16SrRNA基因序列的系统发育分析,确定3株菌分别为Halomonas elongata、Halomonas xianhensis和Oceanobacillus iheyensis。[结论]从盐碱土中获得3株对人参锈腐病有拮抗作用的嗜(耐)盐碱菌,并进行了鉴定。