Influence of GDD in different growth parameters of potato at agroclimatic condition of Jorhat

A field experiment was carried out during Rabi season, 2016-17 at the Instructional-Cum-Research (ICR) Farm of Assam Agricultural University, Jorhat to study crop-weather relationships of potato grown under different micro-climatic environments: MR-I: 16th November, MR-II: 1st December and MR-III: 16th December with three varieties: Kufri Jyoti, Kufri Pokhraj and Local following a split plot design with four replications. Different growth parameters, viz plant height, leaf area index and total biomass were recorded periodically. With increasing Accumulated growing degree-days (AGDD) significantly increased the plant height, LAI and total biomass in case of all different growth stage. Among all the variety Kufri Pokhraj was found highest Accumulated GDD that was 2822 corresponding to maturity phase. Highest correlation of coefficient in case of biomass was found at maturity phase that was 0.743 (At 5% level of significant).