The effect of perlite particles size and its mixing with peat moss on corms yield of saffron (Crocus sativus L.) in soilless cultivation system

Saffron (Crocus sativus L.) one of the native plants and strategic crops in Iran. Increasing the performance of this product requires the use of modern methods instead of traditional methods. In this study, two separate greenhouse experiments were carried out in order to choose the suitable growth media with different perlite particle size and its mixing ratio with peat moss on corms yield of saffron in soilless conditions. The first experimental treatments included particle sizes of perlite with very fine (less than 0.5 mm), fine (0.5-1 mm), medium perlite (1-1.5 mm), coarse (1.5-2 mm) and very coarse (more than 2 mm), which were 100% volumetric and second experimental treatments, including a with peat moss of 50% perlite with each of the measured measures plus 50% peat moss. The experiments were designed in a completely randomized design with three replications. The results showed that the applied treatments had a significant effect on plant parameters including leaf length, leaf area, fresh leaf weight, dry leaf weight, fresh corms weight, dry corms weight, diameter of daughter corms, and content of daughter corms, chlorophyll a, chlorophyll b, total chlorophyll and carotenoids. Based on the results, the maximum weight of corms (17.89 g) was obtained in a mixed growth media containing of 50% perlite (1-1.5 mm) and 50% peat moss. In general, it can be concluded that when the goal is to increase the yield of saffron through the production of coarse corms in the hydroponic system, the use of mixture of medium sized perlite (1-1.5 mm) with peat moss (at 50:50 v/v peat moss to perlite ratio) is introduced as an optimal growth media.