Evaluation of quantitative relationships between saffron yield and nutrition (on farm trial)

Abstract

In order to relate production of saffron and utilization of nutrients, a study was conducted in 2001 and 2002. Four selected locations for this study were Birjand, Gonabad, Qaen and Torbat-Haydariah, which are the main saffron production centers in Iran. This study was performed in 160 saffron farms, aged between 1 and 5 years. Manure, nitrogen and phosphorous fertilizers showed a positive linear relation with yield and length of flowering, while nitrogen and phosphorous showed a negative linear relation with start of flowering period. Yield of saffron showed a significant and positive correlation with the amount of applied manure and the saffron farms with age 4-5 year had highest yield. Our results showed that manure was the most effective factor in production of saffron. The beneficial effects of manure could be due to slow release of nutrients and enhancing soil physical properties. Stepwise regression analysis of yield and fertilizer application showed that 67 percent of yield variations was attributed to manure and phosphorous application.