Economic injury levels of cotton bollworm at Asembagus
1989
Karmawati, E. (Balai Penelitian Tanaman Rempah dan Obat, Bogor (Indonesia)) | Sosromarsono, S. | Soehardjan, M. | Mattjik, A.A. | Raup, A.
An experiment was conducted at the Asembagus Experimental Garden, East Java to evaluate the economic injury levels of H. armigera at various cotton plant growth stages. The cotton variety used was Deltapine 61. Durations and larval infestation levels used as factors and arranged factorially in a randomized block design with three replications. Based on the observation on the number of bolls and the weight of seed cotton, it was apparent that critical period of cotton plant to larvae was at the plant age of 50-80 days after planting. This suggests that monitoring must be started at 50 days after planting. The older that plant, the higher the economic injury level, i.e: 2.80, 4.03 and 8.04 larvae per 60 plants for plant ages of 50, 60 and 70 days after planting respectively.
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