Effect of Weed Interference on Some Morphological Traits and Yield of Garlic (Allium sativum L.) Accessions under Organic Cultivation

o evaluate the response of different garlic accessions to weed competition in Zanjan, west of Iran, a factorial experiment was carried out based on randomized complete block design with three replications in 2015-2016. Four variety of garlic (Hamedan 1, Hamedan 2, Hamedan 3 and Tarom) at two weed infestation conditions (whole season weed infestation and weed-free) were studied. The results indicated that responses to weed interference were significantly affected by accession. Hamedan 2 and Hamedan 3 accessions showed a considerable reduction in most traits under weed competitions while Tarom accession showed highest reduction that was most likely due to low competitive ability. Overall, Hamedan1 accession is recommended for cultivation in cool season regions such as Zanjan, due to the higher yield and lower yield decreases under weedy conditions.