DOI: 10.36347/sjavs.2020.v07i02.005

Pages: 47-55

The present study was carried out in the farmer's field at Dashpara Sylhet and the research laboratory and farm of the Department of Crop Botany and Tea Production Technology at Sylhet Agricultural University, Sylhet. The study was carried out during October 2016 to May 2017 to study the effect of planting dates on growth and yield of sweetpotato (Ipomoea batatas L.) genotypes. The study was done under three planting date’s viz. 10 October, 10 November and 10 December. Six genotypes evaluated in the study were Bangladeshi namely BSP-1(Tripti), BSP-2 (Kamalasundori), BSP-5, BSP-8, BSP-12 and Local-6. The experiment was laid out in a Randomized Completely Block Design (RCBD). The field was divided into 3 blocks for 3 replications. Data on the morphological characteristics, growth studies and yield parameters were recorded at 150 days after planting (DAP) at final harvest. Results revealed that the morphological characteristics, dry matter partitioning and yield attributing parameters varied among the genotypes and planting dates. From the present findings, it was found that better genotypes, which in regard to vegetative growth parameters gave low yields. The Local-6 genotype was grown vigorously but produced poor storage root. In respect of interaction effect, BSP-5 planted on 10 November showed the highest number of leaves (332.67) and total leaf area (13727.60 cm2 plant-1), whereas the same genotype planted on 10 October showed the lowest number of primary (2.00) and secondary (3.00) vines and the lowest number of leaves plant-1 (70.00). BSP-12 planted on 10 November showed maximum total fresh weight (1664.57 g plant- 1) after check genotype (1761.17 g plant-1) and BSP-12 planted on 10 December 2016 showed maximum total dry weight (457.73 g plant-1) after check genotype (618.60 g plant-1). The highest root yield was found in BSP-12 (88.30 t ha-1), planted on 10 November and the lowest yield was found in BSP-5 (22.53 t ha-1), planted on 10 October. BSP-12 ..........