The Resistance Level And Biological Control Of Glyphosate In The Cotton Field Of The Cotton Field In Central China

The resistance level of Eleusine indica collected from fourteen countries in cotton fields in central china to Glyphosate were identified by the whole seedlings test. A sensitive population and four high resistant populations relatively were measured by a spectrophotometer to detect the change of the accumulation of shikimate after application of glyphosate. The whole seedlings test showed that the whole collected populations of Eleusine indica had different resistant to glyphosate, the resistances in the range of multiples of 1.70 to 11.35. The highest degree of resistance population was Furong Village of Jiangxi Province and the relative resistance multiple up to 11.35 compared to Zhang Gongmiao Village of Hunan Province. The shikimate test showed that the content of the aerial parts of the plant appeared an upward trend in nine days after spraying glyphosate and the accumulation of sensitive population was higher than the other four resistant populations. The shikimate accumulation and the level of resistance negatively correlated. Study on the resistance of Eleusine indica to glyphosate in cotton field to delay the occurrence of resistant weeds and provide theoretical foundation for the control of resistant weeds.The strain MT-3 was isolated from diseased leaves in cotton fields naturally infected weeds in Hunan Province, had the potential to further development of cotton fields to become resistant Eleusine indica biological herbicide. The fresh and heavy effect of Eleusine indica was invested ten days later after inoculated mycelium suspension. The fresh and heavy of different leaf stages of Eleusine indica were 82.43%、71.33%、53.60%. The resistant Eleusine indica became wither to death after treated by strain fermentation liquid. The host range test results showed that the strain was not pathogenic to cotton and high pathogenic to Chloris virgata Sw.、Euphorbia lathyris L. and slight pathogenic to Portulaca oleracea L.、Eclipta prostrata. Based on morphological identification and sequence analysis, strain MT-3 was identified as Curvularia intermedia Baedijn.The biological characteristic of the strain was tested to clarify the physiological characteristics and make use of the strain to biological control. It showed the strain had the fastest growth rate in PSA medium and colony diameter was 5.75cm in six days later. The optimum growth temperature was 28℃ and the optimum pH was 6.0. Full illumination condition was favourable for the growth of the strain. The results showed that the strain was good adaptability to the environmenet and the mycelium was easy to propagate. It showed the great prospects for developing to potential microbial-product herbicide.