紫花苜蓿12种镰刀菌的菌落生长和产孢条件

Colonial Growth and Sporulation Conditions of 12 Fusarium spp.in Alfalfa

为明确紫花苜蓿不同镰刀菌的生长和产孢条件,以采自内蒙古不同地区紫花苜蓿根部的锐顶镰刀菌、茄病镰刀菌、木贼镰刀菌、变红镰刀菌、尖孢镰刀菌、燕麦镰刀菌、轮枝镰刀菌、层出镰刀菌、镰形镰刀菌、三线镰刀菌、F.virguliforme和芬芳镰刀菌为研究对象,测定其在不同温度、pH值、碳源和氮源培养条件下的菌落直径、产孢量及其菌丝致死温度。结果表明,不同种类镰刀菌的菌落生长和产孢均受温度、pH值、碳源和氮源的影响,不同菌种在同一培养条件下的菌落直径和产孢量存在显著性差异,同一菌种在不同培养条件下的菌落直径和产孢量也存在显著性差异。不同菌种的最佳培养条件各不相同,但其最适生长温度范围为20~30℃,最适产孢温度范围为15~30℃,最适生长和最适产孢pH值范围较广,最适生长碳源有蔗糖、可溶性淀粉、D-甘露醇、丙三醇和可溶性淀粉,最适产孢碳源有D-山梨醇、可溶性淀粉、羧甲基纤维素钠、D-半乳糖、D-果糖和丙三醇,最适生长氮源有牛肉膏、甘氨酸和硝酸钠,最适产孢氮源有牛肉膏、L-脯氨酸、硝酸钠、胰蛋白胨和硫酸铵。菌丝致死温度范围为50~70℃。在多数供试培养条件下,12个菌种中燕麦镰刀菌和芬芳镰刀菌菌落直径较大,层出镰刀菌和轮枝镰刀菌产孢量较高。

In order to clarify the growth and sporulation conditions of different Fusarium spp.in alfalfa,twelve Fusarium species isolated from the roots of alfalfa in Inner Mongolia were studied,including F.acumi⁃natum,F.solani,F.equiseti,F.incarnatum,F.oxysporum,F.avenaceum,F.verticillioides,F.pro⁃liferatum,F.falciforme,F.tricinctum,F.virguliforme and F.redolens.The colony diameter,spore production and lethal temperature of Fusarium were determined under different temperature,pH,carbon and nitrogen source.The results showed that the colony growth and sporulation of different Fusarium species were affected by temperature,pH,carbon and nitrogen source.There were significant differences in the colony diam‐eter and sporulation of the different strain under the same culture conditions,and there were also significant differences in the colony diameter and sporulation of the same strains under different culture conditions.The optimum culture conditions for different strains were different,but the optimal growth temperature range was 20~30℃,the optimum sporulation temperature range was 15~30℃.The optimal growth and optimal sporulation pH range were wide.The optimal growth carbon sources were sucrose,soluble starch,D-mannitol,glycerol and soluble starch,the optimal sporulation carbon sources were D-sorbitol,soluble starch,sodium carboxymethyl cellulose,D-galactose,D-fructose and glycerol,the most suitable nitrogen sources for growth were beef extract,glycine and sodium nitrate,and the most suitable nitrogen sources for sporulation were beef extract,L-proline,sodium nitrate,tryptone and ammonium sulfate.The lethal temperature range of 12 Fusarium mycelium was 50~70°C.Under most of experimental culture conditions,the colony diameters of F.avenaceum and F.redolens were larger,and the sporulation of F.proliferatum and F.verticillioides were higher among 12 Fusarium mycelium.