INFLUENCE OF BIOSTIMULANTS WITH REDUCED RATE OF CHEMICAL FERTILIZATION AND DEHAULMING SCHEDULE ON POTATO

Abstract

The experiment was conducted at the Horticulture Farm of Sher-e-Bangla Agricultural University, Sher-e-Bangla Nagar, Dhaka-1207, Bangladesh to find out the effect of biostimulants with reduced rate of chemical fertilization and dehaulming schedule on potato during the period from November, 2019 to March, 2020. The variety BARI Alu25 (Asterix) was used in the experiment as the test crop. The experiment consisted of

two factors: Factor A: biostimulants with reduced rate of chemical fertilizer viz. M 1

= 6 t ha -1 vermicompost, M 2 = Recommended NPK, M 3 = 90% NPK+ Trichoderma 4 kg ha -1 , M 4 = 80% NPK+ Trichoderma 8 kg ha -1 .

B: different days of dehaulming I 1 = 65 Days after planting, I 2 = 75 Days after planting, I 3 = 85 Days after planting. There were 12 treatment combinations and experiment was setup in Randomized Complete Block Design (RCBD) with three replications. The result indicated significant variations in number of tubers per hill, weight of tubers per hill, mean tuber weight, yield of tuber per hill, yield of tuber (t ha -1 ), marketable yield, non-marketable yield (t ha ), grade of tuber by number, total soluble solids, firmness, starch percentage, dry matter, water percentage, skin color of potato due to biostimulants with reduced rate of chemical fertilization and/or different days of dehaulming. Results also revealed that, the highest yield contributing characters and tuber quality attributes were obtained from 80% NPK+ Trichoderma 8 kg ha -1 (M 4 ) treatment. Different days of dehaulming significantly influenced the quality attributes of potato but had non-significant variation on yield contributing characters. The highest tuber yield and quality characters were obtained from dehaulming at 85 days. Among the treatment combination, M 4 (80% NPK+ Trichoderma 8 kg ha -1 and dehaulming at 85 days) treatment seemed to be more promising for obtaining higher tuber yield (26.63 t ha -1 ), total soluble solids (6.68), firmness (46.65), starch content (22.38%), dry matter (35.74%) than other treatment combination. Hence, we can summarized that 80% NPK+ Trichoderma 8 kg ha and dehaulming at 85 days given the maximum output in terms of yield and quality contributing characters compared to other treatments.