Evaluation of saffron irrigation and nutritional management among different farmers groups compared to experts recommendations

This research was conducted using questionnaires and the analysis of soil samples (the content of organic matter, nitrogen, phosphorus and potassium) obtained from saffron fields of Torbat-Heydariyeh, Iran, during 2020-2021. In this research, saffron irrigation and nutrition management methods among three farmer groups (progressive farmers, skilled farmers and ordinary farmers) were investigated and compared with the recommendations of saffron researchers. The classification of farmers in the mentioned three classes was based on the stigma yield in relation to the field age. The results showed that most of the progressive and skilled farmers used the combined nutrition management method (organic fertilizer + chemical fertilizer with frequency of about 65%), while the single application of chemical fertilizer was the most common method among ordinary farmers (47.5%). The mean amount of organic manure application for ordinary, skilled and progressive farmers was 5.0, 6.3 and 10.7 ton ha-1year-1, respectively (less than the amount of 19.2 tons recommended by researchers) and the mean amount of nitrogen application was 49.5, 56.5 and 87 kg ha-1 (compared with 93.3 kg recommended by researchers). The application of phosphorus and particularly potassium was not a common practice among all three groups’ farmers. The average content of organic matter in the fields was 0.68%, nitrogen 0.041%, phosphorus 16.1ppm and potassium 292 ppm, which indicates the poverty of soils in terms of organic matter and to some extent nitrogen. The foliar application of nutrients for the fields of ordinary, skilled and progressive farmers was 0.23, 0.65 and 1.00 times per year, respectively, and the average irrigation times was 3.2, 3.6, and 4.6 times per year, respectively, which is less than the recommended values by experts (2.55 and 5.8 times per year, respectively). Summer irrigation (44.4% of farmers) and sprinkle irrigation method (26.8% of farmers) were more common among progressive farmers. In general, the poverty of organic matter and lack of nitrogen in the soil, low foliar application of nutrients and lack of use of modern irrigation methods were among the most important reasons for the high gap yield of saffron fields.