Enhancing yield attributes in rainfed upland rice through incorporation of 6-benzylaminopurine in the cultivation program

This experiment was carried out to evaluate the response of two upland rice varieties to incorporation of 6-benzylaminopurine (6-BAP) into the traditional fertilizer program. Treatments were laid out in a randomized complete block design (RCBD) in 2 x 5 x 2 factorial including 2 upland rice varieties (NERICA 3 (N3) and NERICA 8 (N8)), 5 treatments notably T0 = Controls (NPK 20:10:10 and Urea 46%), T1 = 6-BAP (25mg/l), T2 = 6-BAP (50mg/l), T3 = 6-BAP (75mg/l) and T4 = 6-BAP (100mg/l) all repeated twice. All the treatments received NPK (20:10:10) + Urea 46% while application of T1 to T4 started at the flag leaf stage and was done in 3 splits of foliar sprays. The results revealed that 6-BAP significantly influenced mean number of stay green tillers/m2 at 120 days after transplanting with corresponding scores of 16, 87.5, 111, 110 and 127 for T0, T1, T2, T3 and T4 in Nerica 3. Maximum paddy yield in N3 were 8.37 and 4.49 t/ha respectively for T3 and T0 while in N8, paddy yields were 7.36 and 4.6 t/ha correspondingly for T4 and T0. In N3, broken grains rate after milling was 34.45 and 26.30 % individually for the control and T3 while in N8 grain breaking rate of 28.81 and 25.16 % were respectively scored by T0 and T3. This study reveals that, foliar spray of 6-benzylaminopurine at 75 mg/l in three splits of 7 days during flag leaf stage optimizes upland NERICA yields and grain morphological characteristics after milling.