INTEGRATED MANAGEMENT OF THE WHITE FLY (Bemisia argentifolii) WITH PAECILOTROPICO (Paecilomyces lilacinus) IN THE WATERMELON CROP
The watermelon is one of the most knowleged tropical fruits and of more demand from developed countries; it is cultivated in hot climates and low rain regimes. The main productive zones of this crop in Colombia are the Atlantic coast, the Cauca´s valley, Santander and recently Tolima, where the crop has showed a considerable increase. The insect pests that affect the watermelon represent one of the most common problems that techniques and growers must face due to the great impact on the crop productivity.
The white fly (Bemisia argentifolii) has been considered of economic importance in the watermelon crop in Colombia, but in the last ten years their populations and crop damages are more significant, affecting crops as cotton, soybean, tomato, beans, peanut and others that can grow in the same zone; as the same insecticides are used in these crops for the control of this pest, pest resistance and control costs of management increase.
In order to evaluate the commercial formulation of the biological product PAECILOTROPICO, alone and mixed with the biological product BOVETROPICO, for the white fly control of the watermelon crop, within an Integrated Pest Management Program (IPM) concept, two trials were taken out at different places, at the locality of Espinal, Tolima, with different agronomic management but similar agro ecologic conditions. The application of the treatments was started between three and five days after transplant of the crop, taking into account that the first infestations appear in this stage. The sprayings continued each eight to ten days approximately, maintaining infestation levels bellow the economic damage level (EDL), which was established at three adults per leaf.
According to the results and direct observations made at field conditions it can be established that the white fly, Bemisia argentifolii, is a key pest of the watermelon crop with high levels of resistance to the conventional insecticides, widely employed for its control, which has highly incremented its management costs. However, the entomopathogenic fungi and other forms of biological control are compatible with insecticides within an IPM program of the pest.
The entomopathogenic fungi, Paecilomyces lilacinus, in the commercial product PAECILOTRÓPICO and Beauveria bassiana, in the commercial product BOVETRÓPICO, alone or mixed, are an economic alternative and environmentally sustainable, as a basis line in an IPM program of the pest. Although their action is not based on total control, their effectivity is enough to conserve and maintain the populations of the pest bellow the EDL, which is the goal of each IPM program. PAECILOTRÓPICO at 400 y 800 g/ha dose and the mixture of PAECILOTRÓPICO + BOVETRÓPICO (B. bassiana) at (200 + 200) g/ha dose, showed the same behavior and activity in both field trials made, maintaining adults and nymphs populations bellow the EDL and showing lower costs than conventional insecticides.