| According to the status of planting flowers in Kunming, the thesis studied the biological characteristics, occurrent regularity and abiotic influencing factors of the beet armyworm (Laphygma exigua Hiibner). The control techniques were also investgated and proved. The major results were as following:1. The results of biological characteristics research showed that the occurrence of the beet armyworm was 5~6 generations eash year on flowers in Kunming. The development of nits, larvae, pupae and adults were 3~9d, 19~40d, 6~29d and 4~10d, respectively.2. The damage of the beet armyworm in greenhouse occurred in whole year. The adults had many occurrent peaks from April to October. The larvaes had several occurrent peaks and damaging dates from March to September.3. The abiotic factors affecting the beet armyworm population in greenhouse had been analysed using grade relation analysis of grey system from 2000-2003. The results showed that the first important factor was average temperature of each month, the second one was relative humidity (RH), the third one was the lowest temperature in the whole year. However, the main affecting factors during years were rainfall and the lowest temperature in one year.4. The results of pesticides trial showed that chlorfenapyr (1249.5ppm/ha), Methoxyfenozide (499.5ppm/ha) and indoxacarb(42.9ppm/ha) had good effects against the beet armyworm larvae, the control rates from 3 to 6 days after spraying treatment were 95.7%-100%, 88.7%-100% and 85.2-96.5%, respectively. However, the effect of alpha-cypermethrin (750ppm/ha) was not obvious. Biological insecticides Azadirachtin and pyrethrins also had obvious effects, but the occurring of their effects need a longer period.5. The results of sex pheromones and killing pest lamp against the beet armyworm adults showed that both of them had obvious effects. However, these techniques were difficult for applying in planting flowers in the large scale. |
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