Effect of Planting Dates and Nitrogen Levels on Tuber Quality of Potato cv. Kufri Lima

The experiment was conducted at Research Farm of the Department of Vegetable Science, CCS Haryana Agricultural University, Hisar during winter season of 2020-21. The treatments comprising of three planting dates (25th September, 10th October and 25th October) and four levels of nitrogen (0, 75, 100 and 125% of RDN) were laid out in a randomized block design (factorial) with three replications. Potato tuber quality parameters like dry matter of tubers and haulms, reducing, non-reducing and total sugar were recorded maximum under 10th October planting, whereas, ascorbic acid and specific gravity of tubers were found non-significant. While, among the different nitrogen levels, 125% of RDN application recorded significantly maximum values for reducing, non-reducing and total sugar, while ascorbic acid, dry matter content of tuber as well haulms increased with increase in nitrogen levels upto 100% of RDN. Specific gravity of tubers was found maximum where no nitrogen was applied. The highest values for nitrogen, phosphorus and potassium uptake in haulms and tubers were registered with 10th October planting, whereas, nitrogen uptake in haulms, phosphorus uptake of tubers also found at par with 25th October planting. Among the nitrogen levels, maximum NPK uptake in haulms and tubers were recorded with 125% of RDN application, whereas, phosphorus and potassium uptake by haulms was increased significantly with increasing nitrogen levels upto 100% of RDN application. The leftover NPK in soil after harvest was noted maximum with earlier planting (25th September), while among the different nitrogen levels, leftover nitrogen in soil was increased with increasing levels of nitrogen upto 100% of RDN, while, phosphorus and potassium availability was recorded in reverse trends.