Effect of plant density and corm weight on yield and yield components of saffron (Crocus sativus L.) under soil, hydroponic and plastic tunnel cultivation

Saffron is the most precious spice crop in the world which nowadays has nutritional, medical and industrial importance. Its average yield is 4.83 kg/ha in Iran. The research was conducted to investigate the effect of corm weight and its density on yield and yield components of saffron under soil, hydroponic and plastic tunnel conditions. The effect of three different weights of corm (6-8, 8-10 and more than 10 g) and also three different densities of corm (50, 100 and 150 corms per m²) was investigated in factorial experiment based on CRD with three replications. The traits which were investigated included: number of flower, fresh weight of flower, fresh and dry weight of stigma and style, and economic yield. The results showed that the main effects of bed types. Weight and corm density were significant in all traits. Interactions of bed type and corm weight were significant at 5% except for flower dry weight, and dry weight of stigma + style that were not significant. As well, Interactions of bed type and corm density, corm weight and density and all interactions of bed type, corm weight and density were not significant in all traits. The heavier corms (more than 10 g) provided the highest yield. By decreasing corm weight, all traits were reduced significantly. Also the results showed that least yield(stigma dry weight) obtained from hydroponic cultivation with 50/ m² yielded 4.14 kg/ha and increase in yield (dry weight of stigma) was obtained under soil cultivation and in the density of 150 corms/m² economical yield was equivalent to 7.36 kg/ha in the first year.