This work was carried out to study the effect of cotton leaf worm attack on vegetative growth and its relation with plant phenology. The CNPA 7H and CNPA Precoce 2 cultivars were planted in plastic pots with capacity for 10 kg of soil, and one plant per pot was maintained after pruning. A completely randomized block design was used with seven treatments and four replications. Third-instar caterpillars of Alabama argillacea were used in the experiment, which were originated from a massal rearing creation kept in laboratory. Infestation with caterpillars started 40 days after the planting by identification of leaves that characterized the treatments. The variables analyzed were plant diameter and height in 1996, and plant diameter and height and leaf area in 1997. The attack on primary branch leaves caused reductions in plant diameter and height for both cultivars, whichever growth stage of the plant. In regard to leaf area, greater decreases were observed for treatments that had the main branch leaves wasted away. The most affected one was that in which the attack has occurred after flowering.
Gossypium hirsitum; leaf area; stems; plant developmental stages; pests of plants
