Effects of Nitroxin bio-fertilizer, superabsorbent polymer and planting method on yield of flower and corm of saffron (Crocus sativus L.) in rainfed-farming condition of Khorramabad, Iran

In order to study the effect of bio-fertilizers, planting method and superabsorbent polymer on quantitative yield of saffron under rainfed condition, a factorial experiment based on randomized complete block design with three replications was conducted at the Agricultural Research Station of Khorramabad, Iran during 2015-2016 growing seasons. In this study, Nitroxin bio-fertilizer (consumption 5 Lit/ha and non-consumption), Stockosorb superabsorbent polymer (consumption 240 kg/ha and non-consumption) and planting method (streaking and cluster) was tested. Results showed that triple interactions was significant for number of corm/m2 in first and second year and combined treatment including non-Nitroxin in cluster culture method using superabsorbent with 80.67 corm/m2 for first year and with 183.67 corm/m2 for second year was the superior treatment. Results showed significant differences for number of produced flowers and for fresh and dry weight of stigma in both years; and in the first year, treatment included cluster method cultivation, consumption of superabsorbent and no consumption of Nitroxin was superior; while in the second year, superior treatment was use of superabsorbent, Nitroxin and cluster method. For stigma dry weight of saffron, triple interactions was significant and in the first year, cluster method and consumption of superabsorbent and no usage of Nitroxin was superior (with 0.6 kg/ha), and in the second year, use of Nitroxin and superabsorbent and cluster method was superior (with 0.719 kg/ha). In general, results of the present study in dry-farming conditions over the two years, cluster method cultivation with usage of superabsorbent and Nitroxin could be recommended. Reasons of this recommendation and introduction of the mentioned method are dry climate conditions in area of study and reduction in consumption of chemical fertilizers for development of sustainable agriculture.