Eco-friendly management of seed discolouration of paddy

The current study was carried out for managing paddy seed discolouration using ecofriendly method with native biocontrol strains and their effects on growth and seed quality parameters as seed discolouration is now an emerging complex problem in rice. In dual culture assay, maximum per cent inhibition was recorded in Trichoderma viride (66.62(%)) followed T. harzianum (65.93(%)) whereas, minimum in Talaromyces flavus (33.68 (%)) on the 7th day of incubation. Under field conditions, combination of seed treatment, seedling dip and the spray of T. viride performed better with all plant growth and seed quality parameters. In cultivars PS-5 and P-44 there were healthy seeds (67.32 and 64.39(%), respectively), discoloured seeds (22.10 and 23.03(%)), filled seeds (78.07 and 77.25(%)), unfilled seeds (22.10 and 23.03(%)) and yield (55.20 and 58.28 q/ha), respectively. Whereas, lower performance was observed in control (T10) of PS-5 and P-44 these were healthy seeds (%) (52.98 and 52.09), discoloured seeds (%) (16.51 and 17.98), filled seeds (%) (69.54 and 69.90), unfilled seeds (%) (30.46 and 29.89) and yield (43.43 and 50.72 q/ha) respectively. Similarly, T-7 performed better with respect to seed quality parameters of PS-5 and P-44 these were germination (%) (96 and 94(%)), dry weight (0.0970 and 0.0690 g), seedling length (26.03 and 27.03 cm), SVI-I was maximum in T-7 (2554.19 and 1885.07) SVI-II (9.30 and 6.59) and test weight (24.54 and 16.57 g). Whereas the least performance was seen in T-10 for seed quality parameters germination (%) (68 and 66), seedling dry weight (0.0860 and 0.0600 g) seedling length (19.87 and 22.50 cm), SVI-I (1445.67 and 1473.64), SVI-II (5.86 and 4.07) and test weight (24.04 and 16.22 g) respectively. Our results clearly show that grain discolouration can be efficiently managed using the native Trichoderma viride strain.