The effects of potassium fertilizers on flowering, vegetative growth, and daughter corm yield of potted saffron

Saffron is a highly priced crop that could be potentially produced in the arid and semi -arid areas due to its low water requirements. Fertilization is an important agricultural practice that affects saffron production. Saffron productivity is mainly depending on the number of produced stigma and desirable size of daughter corms. Therefore, the current study was carried out to investigate two different potassium -fertilizers (K -silicate and K -sulphate) at four applied doses (0.5, 1.0, 1.5, and 2.0 g L-1) on growth and productivity of two corm sizes (2.2 - 2.5 and 3.2 - 3.5 cm diameter) of potted saffron. Flowering parameters (number of flowers per plant, and stigma fresh and dry weight) and vegetative growth parameters (plant height, number of leaves, plant fresh and dry weight, and root fresh and dry weight) were recorded. K -silicate fertilizer exhibited the highest values in terms of flowering and vegetative growth parameters compared to K -sulphate, especially when utilizing larger corm sizes. However, a lower dosage of K -sulphate (0.5 g. L-1) enhanced the fresh weight of the stigma. Both sources of potassium improved root growth when compared to the control. Similarly, the utilization of K -silicate fertilizers resulted in higher values of nutrient content and uptake by leaves, corm diameter, and corm fresh weight. Saffron plants that were fertilized with K -sulphate demonstrated higher values of chlorophyll fluorescence and the total number of daughter corms compared to those fertilized with K -silicate, with a preference for larger corm sizes. Our findings indicate that there is a correlation between the type of K -fertilizer and corm size in saffron production. Additionally, a significant improvement in growth and yield of potted saffron was observed with the application of K -silicate.