Response of Two Newly Selected Onion Strains at Different Plant Population

Submit Manuscript | http://medcraveonline.com ecological zones of Pakistan includes Phulkara, Swat-1, Sariab Red, Chiltan-89, Desi Red and Nasarpuri. There always remains need to widen the genetic diversity in onion. Therefore germplasm (five entries) received from Asian Vegetable Research and Development Centre (AVRDC), Taiwan, was primarily evaluated during 2005-06 and 2006-07 along with six cultivated varieties of onion for yield and yield contributing factors at Directorate of Vegetable, NARC. Two selections (NARC Onion-1 & NARC Onion-2) gave better performance with respect to yield. So there is a need to standardize other agronomical and crop management practices (e.g. fertilizer requirement, spacing & planting time etc) for the said best performing strains. Plant population has a large influence on onion bulb size at harvest because plant competition and lack of available space can restrict bulb enlargement. Environmental factors, crop cultivars and cultural practices have great effect on the yield and quality of the onion crop [1]. Studies from different scientists showed that wider spacing produced larger sized bulbs as compared to closest spacing [2-4]. Rumpel et al. [5] had obtained maximum marketable yield with smaller bulb size from high density plants (80p/m2) as compared to densities of 40 and 60p/m2. Also onion cultivars respond differently to different plant densities. Dawar et al. [6] reported that lower planting density (40 plants/4m2) in three onion varieties (Swat-1, Terich-02 and Gilassi local) increased the bulb weight as compared to 60, 80 plants/4m2. Therefore a study was planned during the cropping year 2011-12 to standardize plant spacing for the said onion strains (NARC Onion-1 & NARC Onion-2).