| Standing milkvetch(Astragalus adsurgens) is only cultured in China as forage. However, its planting was limited by severely occurred diseases and insects, in which a stem-boring insects, Grapholita shadawana, and a seed feeding insect, Bruchophagus roddi, have not effectively controlled, and some of their dynamics have not determined yet. This thesis is to study their life cycle, occurrence, damaging characteristics, and medical control. The main results as follows:1 Firstly found Swainsonia salsula was the second host of G. shadawana. The insect on the vetch initially came from the wild grown plant. Therefore, S. salsula probably is an original host of G. shadawana.2 One hundred percentage of vetch plants was damaged by G. shadawana both in 2014 and 2015. There were 64.5 larv and 67.42 larv per 100 stems respectively in both years. Plant damaging percentage in 2015 and larv amount per 100 stems in both years were significantly higher than in S. salsula in Heping County and Dingyuan County. However, the amount in S. salsula in Heping County was significantly higher than in Dingyuan County.3 G. shadawana had two eclosion peaks both in laboratory and in field. The period for eclosion was 60 d in laboratory, but was 75 d in field. The insect reach laying egg peak after 3-5d, and the duration of egg stage was 15 d. The loss caused the insect was 2089.30kg/ha for forage yield, and 49.30kg/ha for seed yield.4 The insect overwintered in vetch seeds at 3 instar larv. Moth emerged in middle June in next year, late July, and late August respectively for overwintered generation, first generation, and second generation.5 G. shadawana larv in vetch stems in September and next March was significantly decreased after applying Emamectin monosultap diluted to 500 times by the means of irrigation. Control efficiency was 33.38% and 56.29%. |
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