菜豆象检验鉴定及处理研究

本文就菜豆象的生物学特性、适生性及检验处理技术进行了研究，认为菜豆象在北纬４１°～４４°地域，每年可发生４代，论证了菜豆象在延边地区的适生能力；采用了５种除害处理方法进行灭虫处理研究。     

营养元素对木霉菌防治甜瓜枯萎病效果的影响

为明确各种营养元素在木霉菌防治甜瓜枯萎病生防体系中的作用,研究了9种营养元素铜、锌、铁、硼、钼、钙、锰、镁及钾对甜瓜枯萎病菌菌丝生长、木霉菌T23菌丝生长及产孢量、甜瓜种子萌发及根系生长的影响.结果表明:10～1000μg/mL的硫酸铜、硫酸锌、硫酸亚铁及硼酸对镰孢菌菌丝生长有较强的抑制作用,而对木霉菌的抑制作用远小于镰孢菌.适量加入钼酸铵、硫酸亚铁、硫酸钙及磷酸二氢钾有利于木霉菌菌丝生长及孢子形成,对甜瓜种子萌发及胚根生长也有较强的刺激作用.木霉菌结合钼酸铵、硫酸锰和硫酸钙处理土壤能显著降低甜瓜枯萎病的病情指数,相对防效分别为73.95%、73.77%和71.36%.     

菜豆新品种将军油豆的选育

将军油豆是以农家品种大马掌为母本 ,家雀蛋为父本人工杂交后系统选育而成。中熟 ,蔓生 ,从播种到采收 6 5d(天 ) ,生长势强 ,嫩荚绿色 ,扁条形 ,荚尖部有红条纹 ,平均荚长 2 0cm ,荚宽 2 .4cm ,单荚质量 2 4g ,纤维少 ,肉质面 ,属典型的东北优质油豆角类型。抗炭疽病、锈病 ,适应性广 ,春秋皆可种植 ,露地、保护地兼用     

Simple diagnosis using ethanol immersion of strawberry plants with latent infection by Colletotrichum acutatum, Dendrophoma obscurans, and Fusarium oxysporum f. sp. fragariae

Simple diagnosis by ethanol immersion (SDEI) to detect Glomerella cingulata was used to detect three other fungi that also cause latent infection of strawberry plants. Signs on strawberry leaves with asymptomatic latent infection by Colletotrichum acutatum became visible using SDEI. Salmon-pink conidial masses were produced in the acervuli on the treated leaves 5 days after incubation at 28°C. In the case of Dendrophoma obscurans, pycnidia with amber conidial masses formed 5 days after incubation at 28°C. The pycnidia were observed mainly on the ribs, and conidial masses exuded from the ostiole. These macroscopic conidial masses were similar to those of G. cingulata and C. acutatum. When water was dripped onto a lesion caused by D. obscurans, the pycnidia exuded white filamentous conidial masses, making the distinction of D. obscurans from G. cingulata or C. acutatum. On petioles with latent infection by Fusarium oxysporum f. sp. fragariae, white aerial hyphae grew out from the vascular tissues on the cut surface 3 days after incubation at 28°C and were easily observed by eye or with a loupe. Thus, SDEI was also useful for diagnosing latent infection of strawberry plants by C. acutatum, D. obscurans, and F. oxysporum f. sp. fragariae.     

Effects of straw and silicon soil amendments on some foliar and stem-base diseases in pot-grown winter wheat

Four foliar and two stem-base pathogens were inoculated onto wheat plants grown in different substrates in pot experiments. Soils from four different UK locations were each treated in three ways: (i) straw incorporated in the field at 10 t ha⁻¹ several months previously; (ii) silicon fertilization at 100 mg L⁻¹ during the experiment; and (iii) no amendments. A sand and vermiculite mix was used with and without silicon amendment. The silicon treatment increased plant silica concentrations in all experiments, but incorporating straw was not associated with raised plant silica concentrations. Blumeria graminis and Puccinia recondita were inoculated by shaking infected plants over the test plants, followed by suitable humid periods. The silicon treatment reduced powdery mildew ( B. graminis ) substantially in sand and vermiculite and in two of the soils, but there were no effects on the slight infection by brown rust ( P. recondita ). Phaeosphaeria nodorum and Mycosphaerella graminicola were inoculated as conidial suspensions. Leaf spot caused by P. nodorum was reduced in silicon-amended sand and vermiculite; soil was not tested. Symptoms of septoria leaf blotch caused by M. graminicola were reduced by silicon amendment in a severely infected sand and vermiculite experiment but not in soil or a slightly infected sand and vermiculite experiment. Oculimacula yallundae (eyespot) and Fusarium culmorum (brown foot rot) were inoculated as agar plugs on the stem base. Severity of O. yallundae was reduced by silicon amendment of two of the soils but not sand and vermiculite; brown foot rot symptoms caused by F. culmorum were unaffected by silicon amendment. The straw treatment reduced severity of powdery mildew but did not detectably affect the other pathogens. Both straw and silicon treatments appeared to increase plant resistance to all diseases only under high disease pressure.     

The Effect of Inoculation Treatment and Long-term Application of Moisture on Fusarium Head Blight Symptoms and Deoxynivalenol Contamination in Wheat Grains

Fusarium head blight (FHB) is an important disease of wheat, which can result in the contamination of grains with mycotoxins such as deoxynivalenol (DON). Artificial inoculation of flowering ears with conidial suspensions is widely used to study FHB diseases. Our goal was to compare four inoculation treatments in which a conidial suspension was sprayed on flowering ears and to study the effect of the application of moisture during kernel setting and filling with a mist-irrigation system. Ten wheat genotypes were inoculated with a DON-producing Fusarium culmorum strain. Inoculation treatments varied in time of application of the inoculum (morning or evening) and in the method of controlling humidity during inoculation (bagging or mist irrigation). A wet season was simulated with a mist-irrigation system, keeping the crop canopy wet for at least 26 days after flowering. The severity of FHB symptoms (area under disease progress curve (AUDPC)), yield loss and DON contamination in the grains were determined. AUDPC data obtained with the different inoculation treatments were highly correlated (r=0.85–0.95). Mist irrigation after inoculation resulted in a higher mean disease severity, but in a overall lower toxin contamination as compared to the non-irrigated treatments. Genotypic differences in DON accumulation were present: for one wheat line toxin contamination significantly increased when irrigated, while two genotypes accumulated significantly less toxin. The closest relationships (r=0.73–0.89) between the visual symptoms and the DON content were obtained under moderate mean infection pressure. This relation between visual symptoms and the DON content deteriorated at higher infection levels.     

Processing traits and digestibility of extruded dog foods with soy protein concentrate

Soya bean protein concentrate (SPC) with two particle sizes were evaluated on extrusion parameters, kibble formation, digestibility and palatability of dog foods. Eight diets were extruded: PBM—control diet based on poultry by‐product meal (PBM); GM—a diet in which corn gluten meal (GM) replaced 45% of the diet protein; cSPC15%, cSPC30% and cSPC45%—diets in which SPC of coarse particle size (600 μm) replaced 15%, 30% and 45% of the diet protein; and sSPC15%, sSPC30% and sSPC45%—diets in which SPC of small particle size (200 μm) replaced 15%, 30% and 45% of the diet protein. The digestibility of nutrients was evaluated for the PBM, GM, cSPC45% and sSPC45% diets, using six dogs per food. The PBM, GM and cSPC45% diets were compared for palatability. Data were submitted for analysis of variance, and the means were compared by polynomial contrasts or Tukey's test (p < .05). The cSPC increased the specific mechanical energy (SME) application, extrusion temperature and pressure linearly, resulting in lower kibble density and higher expansion and starch gelatinization (SG) (p < .01). When comparing the PBM, GM, cSPC45% and sSPC45% diets, higher SME, extrusion temperature and pressure, SG and kibble expansion were verified for the cSPC45% diet (p < .05). The DM, fat and crude protein digestibility were similar among diets. Faecal pH, ammonia and lactate did not differ, demonstrating that the removal of oligosaccharides and soluble non‐starch polysaccharides of SPC produces an ingredient with mostly non‐fermentable fibre. Dogs preferred the PBM to the GM diet (p < .05), but consumed the PBM and cSPC45% foods equally. In conclusion, SPC exhibited good extrusion functionality, favouring kibble expansion and SG, with high digestibility, similar to that of PBM. The removal of soluble compounds from soya beans resulted in an ingredient with low fermentable fibre content, which did not alter faecal formation or characteristics.     

火龙果镰刀菌果腐病病原菌鉴定及生物学特性研究

采用形态学特征观察、rDNA-ITS序列、EF-1α序列比对和系统发育树分析的方法对引起火龙果镰刀菌果腐病病原菌进行鉴定,并初步研究其生物学特性。结果表明:引起火龙果镰刀菌果腐病是单隔镰刀菌(Fusarium dimerum Penzig in Saccardo),这是该菌引起火龙果果腐病在国内的首次报道。该菌菌丝生长的适宜温度25~35℃,最适温度30℃,适宜产孢温度25~35℃,最适产孢温度30~35℃,致死温度75℃(10 min);适宜pH5~9,最适pH7,最适产孢pH4;连续光照、D-果糖为碳源、牛肉膏和蛋白胨为氮源时最有利于该菌菌丝生长;完全黑暗、D-半乳糖为碳源、尿素为氮源时最有利于该菌产孢。综合分析认为,该菌耐高温,光照充足、弱酸和富含有机营养的环境有利于该菌的生长和繁殖。     

提取剂对大蒜鳞茎提取液抑制黄瓜枯萎病的效应

为反映提取剂类型对大蒜鳞茎提取液抑菌能力的影响,用水、乙醇,丙三醇作为大蒜鳞茎杀菌物质的提取剂,采用孢子萌发法对黄瓜镰刀菌枯萎病菌孢子抑杀.研究结果表明,3种提取溶剂制成的大蒜鳞茎提取液对枯萎病菌孢子抑制的EC50值分别为0.2884%、0.2818%和0.2454%,较低的提取液浓度达到了较好的抑菌效果.水、乙醇、丙三醇都可以作为大蒜鳞茎的提取剂,3种提取溶剂的大蒜鳞茎提取液毒力相当,孢子抑制萌发率随着大蒜鳞茎提取液浓度增加而升高.