关键词: 复合微生物菌剂, 柴达木盆地, 燕麦生长, 根系发育

Abstract: To investigate the effects of compound microbial agents on the growth of oat （Avena sativa） in the Qaidam Basin， oat variety ‘Qingtian No.1’ was used as the experimental material. Three treatments were set up： a control （CK）， application of compound microbial agent at 75 kg·hm^-2 （B₁）， and 150 kg·hm^-2 （B₂）. Indicators such as plant height， biomass， chlorophyll content， root characteristics， and dry matter accumulation of oats were measured at the jointing stage， flowering stage， and dough stage to explore the effects of different application rates of the compound microbial agents on oat growth and root development. The results showed that： At the jointing stage， both B₁ and B₂ treatments significantly increased plant height， chlorophyll content， and biomass （P<0.05）. The B₂ treatment significantly enhanced all root indicators （P<0.05）， and oat yield showed a significant positive correlation with fresh weight and chlorophyll content （P<0.05）. At the flowering stage， both B₁ and B₂ treatments significantly increased plant height （P<0.05）， while the B₁ treatment significantly enhanced biomass （P<0.05）. At the dough stage， both B₁ and B₂ treatments significantly promoted the accumulation of chlorophyll content （P<0.05）. The B₁ treatment significantly increased plant height， while the B₂ treatment significantly increased the number of root tips （P<0.05）. Additionally， oat yield was significantly positively correlated with plant height and root surface area （P<0.05）. In summary， the application of 75 kg·hm^-2 of compound microbial agents exhibited the optimal promoting effect on aboveground oat growth and dry matter accumulation， while the application of 150 kg·hm^-2 was more beneficial for the development of underground root systems. These findings provide a theoretical basis for exploring microbial fertilizer technologies and methods to enhance forage cultivation in the Qaidam Basin.

Key words: Composite microbial fungicide, Qaidam Basin, Oat growth, Root development