Effect of Trichoderma harzianum strain (Th 118) on growth and promotion of broccoli plants (Brassica oleracea var. Italica p.)

Abstract

The use of microbial antagonists for integrated disease management constitutes a viable alternative to achieve significant increases in yields. In this sense, the objectives of this work were: i) to evaluate the effect of Trichoderma harzianum (Th118) on plant growth and development in a broccoli crop and ii) to evaluate whether a second application during the crop cycle is necessary to improve plant growth. To do this, a test was carried out at the Gorina Experimental Station. A commercial greenhouse of 10 x 30 m² was used, which was organized into four blocks with the treatments alternating with each other. The trays with the broccoli seedlings were immersed in a suspension of conidia of the T. harzianum strain for 40 minutes, generating irrigation by capillary rise. The treatments were the following: T1: broccoli seedlings without treatment (control); T2: broccoli seedlings treated with T. harzianum (Th118) incorporated as a spore suspension, with a single application during the crop cycle at the seedling stage; T3: booster dose of T. harzianum (Th118) incorporated as a liquid in soil on the crop at V6 stage. The results indicate that the treatment with a dose of T. harzianum presented the highest values and of fresh weight and diameter of the inflorescence; this treatment differs statistically from the others. This is telling us that a booster dose is not necessary to improve plant growth.