Some Vegetative Characteristics of Saffron (Crocus sativus L.) as Affected by Various Fertilizers

In this study, the effects of various fertilizers were evaluated on quantitative and qualitative characteristics of vegetative organs in saffron (Crocus sativus L.). Field study was conducted at the Experimental Farm of the Shahed University using a factorial randomized complete block design. The treatments consisted of three levels of chemical fertilizers (0, 50% and 100% of the recommended amount of fertilizer) and four levels of non-chemical fertilizers (control, vermicompost, bio fertilizer containing Pseudomonas and Bacillus, and integrated application of bio fertilizer and vermicompost). In order to determine the best type of fertilizer in saffron cultivation, characteristics such as physiological attributes, photosynthetic pigments, and leaf chemical elements were measured. The results showed that sole application of bacteria had the greatest effects on morphological characteristics. Application of bacteria along with vermicompost increased the amounts of pigments significantly. Also, integrated application of bacteria, vermicompost, and 100 percent fertilizer was the most effective treatment on leaf chemical elements. Application of plant growth promoting bacteria (PGPR) showed positive effects on most of the studied characteristics: Compared to the control (no fertilizer), it increased leaf length, fresh and dry weight, chlorophyll b, total chlorophyll, carotenoids, zinc, and phosphorus concentrations by, respectively, 61.64%, 79.71%, 82.05%, 4.01%, 4.90%, 4.23%, 20.18% and 20.23%. Because of the environmental and economic importance of inputs in agriculture, it is recommended to use the two types of growth promoting bacteria to achieve the highest quantitative and qualitative vegetative growth in saffron.