Seed biopriming with Trichoderma species and Pseudomonas fluorescent on growth parameters, enzymes activity and nutritional status of soybean

Abstract

Biopriming treatment is potentially prominent to induce profound changes in plant characteristics and to encourage more uniform seed germination and plants growth associated with fungi and bacteria coatings. In the present study three fungal bio control agents including Trichoderma harzianum (T. AS 19-2, T. bp4, T. BS1-1), T. virens (T.As19-1, T.As17-4, T.As10-5) T. atroviride (T.As18-5, T.cs5-1, T.Cs2-1) and a bacteria; pseudomonas fluorescent (utpf5) were applied on soybean seed and their impact on seedling were evaluated under greenhouse conditions. The effects of 9 strains of Trichoderma and Pseudomonas fluoresecens (UTPF5) in combination of zinc and PEG priming on improving soybean seed germination, seedling growth and chlorophyll amount were investigated. After selection of strains, the efficacy of seed biopriming treatment was compared with seed inoculation and priming treatments. Three strains, including T.h4, T.v7, T.a9 and UTPF5 were selected for next experiments because they improved seed factors such as germination rate and seedling growth indices including root length, seedling length, and dry weight of root. Also they increased seedlings and leaf area per plant and total chlorophyll amount. Biopriming was significantly improved by the application of these strains. Among fungi and bacterial isolates, strain BS1-1(T.h4) of Trichoderma harzianum, showed the highest efficiency and positively affected soybean growth factors. The fungi increased seedling length, root length by 52% and 44% and their dry weight by 55 and 61% and total chlorophyll to 206% respectively (compared with non-inoculated controls). Trichoderma virens As191(T.v7) increased Fe uptake to 77% and UTPF5 increased Zn uptake (90mg/kg), N (7.5%) and total protein (47.1 mg/kg) in comparison with other treatments and control. Biopriming Trichoderma atroviride Cs2-1(T.a9) in combination with bran enhanced activity of glutathione reductase (GR) to 157% compared to control.