Population Fluctuation of Disonycha teapensis Blake (Coleoptera: Chrysomelidae) in Crotalaria longirostrata Hook. & Arn. (Fabales: Fabaceae) in Huimanguillo, Tabasco, Mexico

Resumen

Objective: To establish the population fluctuation of Disonycha teapensis adults and larvae and to determine its relationship with the amount of damaged foliage, temperature, and precipitation.

Methodology: The study was carried out in a n=48 Crotalaria longirostrata plant crop. The following data was recorded every week: number of adults and larvae, damaged leaflets percentage, plant phenology, temperature, and precipitation. Based on these data, monthly averages were calculated, and correlation analysis were performed between the population fluctuation of D. teapensis and the fluctuation of the damaged foliage percentage, temperature, and precipitation.

Results: All the phenological stages of C. longirostrata were affected by the pest, which showed a constant population growth. The population fluctuation resembled the fluctuation of the damaged foliage percentage, with a significant positive correlation between both variables. Regarding temperature and precipitation, the correlation was negative but not significant; therefore, the relationship between population fluctuation and these climatic factors is not clear.

Study Limitations: It was not possible to conduct the study for a full year.

Conclusions: The population development of D. teapensis depends on the increase in the amount of foliage of its host plant. This insect attacks plants in all their phenological stages and the amount of damaged foliage is considerable.