Intra row spacing effect on shelf life of onion varieties (Allium cepa L.) at Aksum, Northern Ethiopia

A field experiment was conducted to investigate the influence of intra-row spacing and, variety on yield and shelf life of onion. The study was conducted between August 2010 and April 2011 at Aksum area (Laelay Maichew District). Three different intra-row spacings (5, 7.5 and 10 cm) were evaluated using 4 varieties of onion (‘Adama’ Red, ‘Bombay’ Red, ‘Melkam’ and ‘Nasik’ Red) using randomized complete block design replicated 4 times. Data on yield and shelf life parameters were recorded and subjected to analysis of variance using SAS 9.2 software. The result showed the post harvest deterioration as measured by percentage of marketable loss, total soluble sugars in oBrix and dry matter content (DMC) was less on ‘Nasik’ Red variety. The largest bulb size, produced by the larger intra-row spacing, showed highest rotting percentage compared to the smaller ones. Average bulb weight loss during storage also was higher at the intra-row spacing of 5 cm than 7.5 cm. Moreover, the result revealed that ‘Melkam’ and ‘Bombay’ Red varieties were superior in yield and an intra-row spacing of 7.5 cm can gave good yield bulbs while ‘Nasik’ Red had best storage quality and ‘Melkam’ and ‘Adama’ Red are moderate.