At present,there are still many difficulties in China s tobacco farmers,such as unreasonable age structure,generally low education level,lack of management ability,and low planting efficiency.It is necessary to cultiv...At present,there are still many difficulties in China s tobacco farmers,such as unreasonable age structure,generally low education level,lack of management ability,and low planting efficiency.It is necessary to cultivate new professional tobacco farmers.Based on the practical problems existing in the cultivation of professional tobacco farmers in China,such as vague screening criteria,lack of pertinence in training content,single training mode,immature evaluation system,insufficient follow-up support and unsystematic cultivation mechanism,this study put forward corresponding strategies and suggestions.展开更多
Eleven isolates of Beauveria spp., including B. bassiana(Bb062) newly isolated from Helicoverpa assulta, and other seven B. bassiana isolates and three B. brongniartii isolates that were originally isolated from diffe...Eleven isolates of Beauveria spp., including B. bassiana(Bb062) newly isolated from Helicoverpa assulta, and other seven B. bassiana isolates and three B. brongniartii isolates that were originally isolated from different geographic origins and various hosts, were tested against the 3^(rd) instar larvae of H. assulta. The protective enzyme activity in the 3^(rd) larvae of H. assulta infected by highly virulent isolate was also assayed. The results showed that the isolate Bb062 had the highest virulence to the 3^(rd) instar larvae among eleven isolates of Beauveria spp., with a corrected mortality reaching 91.07% within 10 d post treatment, and the LT_(50) was 4.67 d. After inoculated with three concentrations(1.0 ×10~6, 1.0 ×10~7 and 1.0×10~8 conidia/mL) of Bb062 conidial suspension, the accumulative mortality of H. assulta larvae increased with the increase of concentration and observation time, and the LC_(50) was 1.82×10~7 conidia/mL. Activities of superoxide dismutase(SOD), peroxidase(POD) and catalase(CAT) in H. assulta larvae first increased rapidly then dropped sharply within 72 h. Bb062 showed high virulence to H. assulta and could inhibit activities of protective enzymes. Therefore, it will be a promising biocontrol agent against H. assulta.展开更多
基金Supported by Science and Technology Project of Guiyang Branch of Guizhou Tobacco Company Study on Cultivation of New Tobacco Management Entities in Guiyang Tobacco-growing Areas (2020-06).
文摘At present,there are still many difficulties in China s tobacco farmers,such as unreasonable age structure,generally low education level,lack of management ability,and low planting efficiency.It is necessary to cultivate new professional tobacco farmers.Based on the practical problems existing in the cultivation of professional tobacco farmers in China,such as vague screening criteria,lack of pertinence in training content,single training mode,immature evaluation system,insufficient follow-up support and unsystematic cultivation mechanism,this study put forward corresponding strategies and suggestions.
基金Supported by General Project of Shandong Branch of China National Tobacco Corporation(KJ20170413)Major Special Project of Guiyang Branch of Guizhou Tobacco Company(2016-06)+2 种基金Natural Science Foundation of Anhui Province(1908085MC70)Key Projects of Natural Science at Higher Institutions in Anhui Province(03087060)Key Projects of China National Tobacco Corp Sichuan Company(SCYC201703&SCYC201806&SCYC2018-2)
文摘Eleven isolates of Beauveria spp., including B. bassiana(Bb062) newly isolated from Helicoverpa assulta, and other seven B. bassiana isolates and three B. brongniartii isolates that were originally isolated from different geographic origins and various hosts, were tested against the 3^(rd) instar larvae of H. assulta. The protective enzyme activity in the 3^(rd) larvae of H. assulta infected by highly virulent isolate was also assayed. The results showed that the isolate Bb062 had the highest virulence to the 3^(rd) instar larvae among eleven isolates of Beauveria spp., with a corrected mortality reaching 91.07% within 10 d post treatment, and the LT_(50) was 4.67 d. After inoculated with three concentrations(1.0 ×10~6, 1.0 ×10~7 and 1.0×10~8 conidia/mL) of Bb062 conidial suspension, the accumulative mortality of H. assulta larvae increased with the increase of concentration and observation time, and the LC_(50) was 1.82×10~7 conidia/mL. Activities of superoxide dismutase(SOD), peroxidase(POD) and catalase(CAT) in H. assulta larvae first increased rapidly then dropped sharply within 72 h. Bb062 showed high virulence to H. assulta and could inhibit activities of protective enzymes. Therefore, it will be a promising biocontrol agent against H. assulta.
