Effect of apple pomace-based Trichoderma inoculants on seedling vigour in pea (Pisum sativum) germinated in potting soil

Three Trichoderma inoculants were produced by growing T. viride, T. harzian um and T, pseudokoningii on apple pomace-based medium at 20 degrees C for 7 days. The Trichoderma inoculants were mixed with potting soil at a ratio o f 1:5 (v/v) and the mixture was used for germination tests of pea (Pisum sa tivum) seeds. When T. viride, T, harzianum and T. pseudokoningii inoculants were applied to the soil, the germination rate of pea seeds increased by 2 0, 40 and 15%, respectively, compared to the potting soil control. After 5 days the average plant height increased by 52, 67 and 48%, respectively, wh ile the average fresh weight of seedlings increased by 26, 63 and 25%, resp ectively. The average total phenolic content of pea seedlings increased by 14, 18, and 12% respectively. Among those three Trichoderma inoculants, how ever, only T. harzianum inoculant increased plant height and fresh weight s ignificantly, while both T. harzianum and T. viride inoculants increased ph enolic content of seedlings significantly. The apple pomace control increas ed the germination rate, plant height and fresh weight slightly, but did no t increase the phenolic content of pea seedlings. These results suggest tha t Trichoderma species grown on apple pomace-based medium can enhance seed p erformance of peas according to some criteria of seedling vigour and thus h ave potential for use as seed treatment. (C) 1999 Elsevier Science Ltd. All rights reserved.