Integrated control of Phytophthora capsici in pepper. I. Effect of antagonist fungi on plant growth.

Magdalena Cruz A.1 y Viviana Cisterna O.

The effect of Trichoderma harzianum, Gliocladium virens and K2HPO4 on the in vitro control of Phytophthora capsici and on the pepper plant growth was evaluated in replicated experiments. The radial growth ofthe pathogen was inhibited in cultures with both antagonists. T. harzianum and G. virens significantly increased (P<0.05) seed germination compared to the control without antagonist. The experiment was carried out twice. T. harzianum treatment in greenhouse revealed a significant increase of root length (P<0.01), root dry weight (P<0.05), plant height (P<0.001), leaf number (P<0.001), leaf dried weight (P<0.01), leaf area (P<0.001), stem diameter (P<0.001) and flowers per plant (P<0.001), related to the non-inoculated treatment. A principal component analysis, showed that the two first principal components accounted for 78% and 85% respectively ofthe total variation in the data oftwo greenhouse experiments. The interpretation agrees with plant growth, and the higher values corresponded to T. harzianum and G. virens treatments.

Keywords: Trichoderma harzianum, Gliocladium virens, Phytophthora capsici, biological and integrated control, pepper, Capsicum annuum.
1 Instituto de Investigaciones Agropecuarias , Centro Regional de Investigación Quilamapu, Casilla 426, Chillán, Chile. mcruz@inia.cl.