Effect of <i>Trichoderma</i> isolates on tomato seedling growth response and nutrient uptake

Abstract

Trichoderma species are commonly used as biological control agents against phytopathogenic fungi and some isolates are able to improve plant growth. In this study, the effects of three Trichoderma isolates including Trichoderma harzianum isolate T969, T. harzianum isolate T447 and Trichoderma sp. isolate T in tomato seedling vigor and their nutrient uptake via two inoculants introduction methods (inoculating seed with Trichoderma spore suspension and inoculating nursery soil with Trichoderma fortified wheat) were examined. Seed germination rate was not affected by Trichoderma application, but shoot height, shoot diameter, shoot fresh and dry weight and root fresh and dry weight in tomato seedlings were interestingly (p ≤ 0.05) increased when sown in Trichoderma sp. T and T. harzianum T969 fortified soil and when compared to the control. The soil amended by Trichoderma sp. T and T. harzianum T969 had marked increase in leaf number and leaf area (p ≤ 0.05). Chlorophyll content increased in seedling grown in Trichoderma sp. T amended soil as well as in Trichoderma sp. T and T. harzianum T969 coated seed. A dramatic increase (p ≤ 0.05) in the concentrations of Ca²⁺, Mg²⁺, P and K⁺ were recorded in the seedling shoot and root among T. harzianum T447 soil amended treatment when compared to the control, except for Na⁺ level in soil amendment with T. harzianum T969 and seedcoating with strain Trichoderma sp. T, which significantly reduced the Na⁺ concentration.

Key words: Growth response, nutrient uptake, tomato seedling, Trichoderma harzianum.