2种复合除草剂降解菌剂的制备与性状分析

研发除草剂降解菌剂是绿色低碳处理除草剂残留的有效途径。采用椰糠载体(玉米粉、椰糠、高岭土、白糖)和海藻酸钠凝珠载体(海藻酸钠、高岭土、甘油)制备草酸青霉菌菌剂载体。结果表明:椰糠制备的载体为粉末状,细碎柔软,呈褐色或白褐色;海藻酸钠凝珠载体为圆形颗粒状,质硬,呈白色或偏黄色。2种菌剂储藏1个月后,菌剂中有效活菌数最低为2.7×1010,1.7×1010个/g,但均高于GB 20287—2006《农用微生物菌剂》标准;海藻酸钠凝珠载体中霉菌数、总杂菌数低于椰糠制备的载体,杂菌率为14.3%~17.3%。椰糠载体含水量普遍较低,为2.88%~5.27%,海藻酸钠凝珠载体含水量为11.53%~13.96%,均低于GB 20287—2006中的35.0%(粉剂)和20.0%(颗粒)。2个载体中的细度质量分数均超过90%,高于GB 20287—2006中的最低限值80.0%。结合GB 20287—2006要求载体pH值为5.5~8.5,确定椰糠载体最佳组分为:玉米粉、椰糠、高岭土、白糖比例为10∶8∶6∶3(质量比,g/g);而海藻酸钠凝珠载体最佳组分为:海藻酸钠2%(质量浓度,g/mL)、高岭土1%(质量浓度,g/mL)、甘油60%(质量比,g/g)。两者相比较,椰糠载体的有效活菌数、杂菌数等占优势,是除草剂降解菌剂较可行的载体。研究结果可为除草剂面源污染的防治提供技术参考。

PREPARATION AND PROPERTY ANALYSIS OF TWO COMPOUND HERBICIDE-DEGRADING MICROBIAL AGENTS

The research and development of herbicide-degrading inoculants is an effective way to solve herbicide residues in a green and low-carbon strategy. In this study, coconut bran carrier (corn flour, coconut bran, kaolin, white sugar) and sodium alginate carrier (sodium alginate, kaolin, glycerin) were used to prepare Penicillium agents. The results showed that the coconut bran carriers were powdery, finely crushed and soft, and were brown or white-brown, while the sodium alginate beads carrier was round granular, hard, and white or yellowish. After one month’s storage, the minimum number of effective viable fungi in both agents was 2.7×1010/g and 1.7×1010/g, higher than the requirements in the microbial inoculum standard of the Microbial Inoculants in Agriculture (GB 20287—2006). The number of molds and the total number of bacteria in the sodium alginate beads carrier was lower than that of the carrier prepared from coconut bran, and the hybrid bacteria rate was 14.3%~17.3%. The water content of coconut bran carrier was generally low, ranging from 2.88%~5.27%, and the water content of sodium alginate beads carrier was 11.53%~13.96%, which was lower than 35.0% (powder) and 20.0% (granule) in GB 20287—2006. The fineness mass fraction in both carriers exceeded 90%, higher than 80.0% in GB 20287—2006. Based on the national standard requirement of the pH value between 5.5~8.5, the best mixing ratio of corn flour, coconut bran, kaolin and white sugar in the coconut bran carrier was 10∶8∶6∶3 (by mass), wherever the sodium alginate beads carrier was: sodium alginate 2% (W/V), kaolin 1% (W/V), glycerin 60% (W/W). Comparing the two carriers by the effective number of viable microbial and hybrid bacteria, the coconut peat carrier was the relatively feasible carrier for herbicide degrading agents. The findings provide good technical support for the prevention and control of herbicide non-point source pollution.