Population dynamics of Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae) and its populations on different planting dates and host plant species

The greenhouse whitefly (GWF), Trialeurodes vaporariorum (Westwood), is a cosmopolitan pest of horticultural crops. The study purpose was to assess the GWF adult population dynamics on potato and its populations on different planting dates and different host plant species. A survey was conducted to determine the GWF population on potato and its associated abiotic factors from January to December 2019. Four crop species, common bean (Phaseolus vulgaris), tomato (Lycopersicon esculentum), potato (Solanum tuberosum), and chili (Capsicum annum) were planted in two field experiments with different planting dates (7 April and 10 July). The results showed that during high rainfall, the GWF densities were very low. However, as the rainfall declined, the population increased and reached its peak in August. Again, when the rain started in September, the population drastically dropped and continuously declined as the rainfall increased until the year-end. The rainfall rate negatively correlates with the GWF population, but there was no significant correlation between temperature and the insect population. Populations of GWF adult, egg, and nymph were significantly higher in planting date 2 than in planting date 1. On both planting dates, the GWF populations on common bean were significantly higher than those on the other host plants. Hence common bean is the potential to be used as a trap crop in potato or chili plantations. Further studies are necessary to develop efficient and effective ways of utilizing bean as a trap crop.