ROLE OF CLYBIO APPLICATION ON SUMMER ONION (Allium cepa) PRODUCTION IN BANGLADESH

A field experiment was conducted at the Horticulture Farm of Sher-e-Bangla Agricultural University, Sher-e-Bangla Nagar, Dhaka, from June to October 2021 to evaluate the influence of Clybio concentrations on summer onions (Allium cepa) production. The variety used was BARI Piaz-3. The single factorial experiments were laid out in a Randomized Complete Block Design (RCBD) with three replications. The experiment consisted of four treatments, namely, T₀ = control (no Clybio application), T₁ = Clybio @ 2 ml/L, T₂ = Clybio @ 4 ml/L and T₃ = Clybio @ 6 ml/L, and in total, this was applied six times, starting from 10 DAT until 60 DAT and was applied in a foliar manner to both leaves and surrounding soil. Among the treatments, the maximum plant height (60.8cm), the number of leaves per plant (16.7), leaf length (54.2cm), leaf weight (31.3g), diameter of pseudo stem (11.9mm), root length (8.4cm), number of roots (33), bulb diameter (43.8mm), bulb length (52.7mm), weight of a single bulb (45.7g), average bulb yield per plot (33.2 t/ha) was recorded at T₃ treatment. The highest length of pseudo stem (49.4 mm) was found in the T₁ treatment. On the contrary, the minimum plant height (38.3cm), number of leaves per plant (7.0), leaf length (24.1cm), leaf weight (17.7g), root length (4.5cm), number of roots (26), bulb diameter (22.7mm), bulb length (42.0mm), weight of a single bulb (22.0g), average bulb yield per plot (16.0 t/ha) was observed at T₀ (control) treatment. The lowest diameter of the pseudo stem was found at the T₁ (7.5mm). No statistically significant variation was found in the length of the pseudo stem (mm) in response to different treatments. When compared to control (T₀), the highest increase in yield percentage was observed at T₃ treatment (107.5%). A highly significant, very strong (R₂ = 0.99) and positive correlation was discovered between bulb weight and root length, indicating that bulb weight increased as root length increased. Considering the aforementioned findings, T₃ (Clybio @ 6 ml/L) treatment delivered the best results in terms of growth and yield attributes of offseason onions.