EFFECT OF TUBER SIZE AND PLANT SPACING ON GROWTH AND YIELD OF SEEDLING TUBER DERIVED FROM TRUE POTATO SEED

Abstract

A field experiment was conducted at the research field of Sher-e-Bangla Agricultural University, Dhaka, during the period from 10 November 2009 to 10 March 2010 to investigate the effect of seed tuber weight and plant spacing on morpho-physiological characters, yield attributes and yield of potato. The experiment comprised of four different weight of seed tubers viz., 40 ± 2, 30 ± 2, 20 ± 2 and 10 ± 2 g and three plant spacing viz., 60 cm × 25 cm, 60 cm × 20 cm and 60 cm × 15 cm. The experiment was laid out in randomized complete block design factorial with three replications. The growth parameters such as plant height, stems hill-1, leaves hill-1, leaf length and breadth, leaf area (LA) plant-1 and leaf area index (LAI), total dry mass (TDM) plant-1 and TDM m-2, crop growth rate (CGR), relative growth rate (RGR) and net assimilation rate (NAR), yield attributes such as tubers hill-1 and tuber weight and tuber yield of gross, marketable and non-marketable were significantly influenced by seed tuber weight and plant spacing. Results revealed that in general, plant height, stems hill-1, LA plant-1 and LAI, TDM plant-1 and TDM m-2 and CGR increased with increasing seed tuber weight but yield attributes and yield increased upto 30±2 g tuber weight. The highest tuber yield ha-1 both gross and marketable was recorded in the tuber weight of 30 ± 2 g due to increased number of tubers hill-1 and tuber yield hill-1. In contrast, the lowest tuber yield ha-1 both gross and marketable was recorded in the smaller seed tuber of 10 ± 2 g. Results showed that stems and leaves hill-1, leaf length and breadth, LA, TDM plant-1, tubers hill-1, single tuber weight and tuber weight hill-1 increased with increasing plant spacing while reverse trend was observed in plant height, LAI, TDM m-2 and CGR. The highest number of stems and leaves hill-1, LA, TDM plant-1, tubers hill-1, single tuber weight and tuber weight hill-1 were observed in the wider spacing of 60 cm × 25 cm and the lowest of the above parameters was observed in the closer spacing of 60 cm × 15 cm. However, the highest gross andmarketable tuber yield ha-1 was observed in the plant spacing of 60 cm × 20 cm and the lowest was recorded in the closer spacing of 60 cm × 15 cm. For combined effect of seed tuber weight and plant spacing, the highest gross and marketable tuber yield was observed in the treatment combination of 40 ± 2 g seed tuber with the plant spacing of 60 cm × 25 cm. But economic point of view with high yield performance, the seed tuber size of 30 ± 2 g with plant spacing of 60 cm × 20 cm was more profitable than those of other treatment combinations.