Evaluation the effects of planting methods and transpling date on earliness and qualitative and quantitative traits of onion genotypes in Khouzestan province;.

This experiment was conducted to determine the optimum planting methods, transplanting date and genotypes to earliness of onion production in Khozestan province at Behbahan Agriculture Research Station and farm of Baghe-e- melek city in two year (2012-14). Experiment was performed in split factorial based on RCBD with three replications. Main plot consisted of two planting methods: transplant and onion set methods. Sub plot consisted of combination of three transplanting dates (23 September, 7 and 23 October) and four genotypes (Improved population of Behbahan onion, Ramhormoz landrace onion, Primavra and Texas early grano cultivars) as factorial. To produced sets , 10-12 grams seeds (of each genotype) were sown per square meter in late February. Sets were harvested in late January. In the first year, in onion set method, the total and marketable yield of 23 octeber transplanting date was higher than other transplanting dates at 1% probability level. Primavera cultivar produced the highest total and marketable yield. The differences of total and marketable yield between transplant and onion set methods in transplanting date of 23 October was not significant. In the seconed year, The effect of transplanting date on total and marketable yield was not significant. Onion set method produced the higset total and marketable yield. The total and marketable yield of Primavera cultivar was higher than other genotypes at 1% probability level. By postponement transplanting date bolted plants and doubling bulbs decreased. According to results to earliness onion production in Khuzestan province planting of Primavera cultivar in onion set method and transplanting date of 23 September is recommended. Key Words: onion, transplanting date, planting method, genotype, earliness