Saffron Agronomy and Technology

Abstract Saffron, despite exhibiting relative resistance to drought stress, is known to experience reduced growth and yield under drought conditions due to its underdeveloped root system. This study aimed to investigate the potential of organic matter in mitigating the adverse effects of drought stress on saffron. A factorial experiment was conducted in a completely randomized design with three replications in the pot at the  University of Torbat Heydarieh in 2023-2024. Treatments included two levels of drought stress (non-stress (90% field capacity) and stress (50% field capacity)) and six levels of organic matter (a mixture of manure and leaf-soil in a 3:1 ratio) applied to the soil at rates of 0, 2. 5, 5, 10, 20, and 40%. The studied traits included leaf length, leaf weight, root weight, corm number, corm weight, water use efficiency, and the concentration and uptake of nitrogen, phosphorus, and potassium. Results showed that across all the OM treatments, drought stress had a negative impact on all growth traits. For instance, water deficit led to a 67% and 58% decrease in average corm weight and stigma DW compared to non-stress conditions, respectively. Nitrogen and potassium concentrations were higher under stress conditions across all organic matter levels, while phosphorus concentration was higher under non-stress conditions. The application of all organic matter levels increased the studied traits under both stress and non-stress conditions, with a more pronounced effect under stress. Under non-stress conditions, there was no significant difference between the 20% and 40% organic matter levels for the studied traits, while under drought stress, the highest values were obtained at the 40% organic matter level, with significant differences compared to other levels. The application of 40% organic matter increased the average corm weight from 13.2 g to 34.8 g under drought stress. At 0, 2. 5, 5, 10, and 20% organic matter levels, water use efficiency was significantly higher under non-stress conditions compared to water deficit, but at the 40% organic matter level, this index was significantly higher under drought stress (1. 82 kg.m-3) than under non-stress conditions (1. 48 kg.m-3). Overall, the results of this study indicated that the application of organic matter can significantly mitigate the negative effects of drought stress and lead to a significant increase in leaf and corm growth of saffron under these conditions. In pot or greenhouse planting, considering the economic efficiency, the application of 20% organic matter is recommended under drought stress conditions. For verification on a larger scale, this experiment needs to be evaluated for field conditions.

Abstract In order to evaluate the effect of last irrigation cut-off time and various fertilizer resources on corm of saffron (Crocus sativus L.), an experiment was conducted in a split-plot arranged as a randomized complete block design with three replications and 18 treatments in a four year research farm of Jihad ministry located in Lalezar village, Bardsir region, Kerman province, in 2015-2016. The experimental treatments were irrigation cut-off time  (conventional time  (5 May), 15 days before the conventional time (20 April) and 15 days after conventional time (20 May)) assigned to main plot, and nutritional resources (cow manure 40 t ha^-1, hen manure15 t.ha^-1, vermicompost 10 t.ha^-1, humic acid 2 kg.ha^-1, and chemical fertilizer containing 200 kg.ha^-1 urea and 140 kg.ha^-1 P and K) as subplot. The analysis of variance results showed that the effect of irrigation cut-off treatment was significant on corm fresh, dry weight and average weight (P≤0.05), but had no significant effect on the number of corm per area and number of buds per corm. The results showed that the delay in irrigation cut-off led to a significant decrease in traits. As such, the highest corm fresh (561.5 g.m^-2) and dry (294.8 g.m^-2) weight and average weight of the corm (4.9 gr) were found in earlier irrigation cut-off treatment (before the conventional time). The effect of fertilizer resources on all the studied traits was significant. All the fertilizer treatments with the exception of humic acid, resulted in a significant increase in corm weight compared to control treatment. Application of vermicompost led to the production of the highest number of corm in m^-2 (137.1), the corm fresh weight (595.6 g.m^-2), dry weight (341 g.m^-2) and average weight (4.30 g). The highest number of buds in corm (3.83) was found in chemical fertilizer treatment. In general, the results showed that irrigation cut-off in April with the using vermicompost had the best conditions for producing saffron corm in the Bardsir region of Kerman.

Abstract Due to climate change it seems that the suitable area for production of saffron is shifting towards the Northern area of Khorasan. On the other hand, corm density and nutrient management are important factors in saffron production. To find out the credibility of this assumption, an experiment was conducted based on a randomized complete blocks design arranged in split plot with three replications in a field located 10 km of Shirvan during the 2013-14, 2014-15 and 2015-16 growing seasons. Corm density (50, 100 and 150 corm.m^-2) and different amounts of chemical and organic manure [No fertilizer (Control), amount of urea, triple super phosphate and potassium sulfate 100, 100, 50 (C1), 200, 200, 100 (C2) and 300, 300, 150 (C3), cow manure consumption based on 100 kg.ha^-1 urea (3066 kg.ha^-1), based on 200 kg.ha^-1 urea (6132 kg.ha^-1) and based on 300 kg.ha^-1 urea (9198 kg.ha^-1)] were allocated to the main and sub-plots, respectively. Three year average of harvest showed that flower and corm traits improved with increasing corm density and cow manure consumption, while the highest density compared to minimum density caused increasing flower number, fresh flower yield, dried stigma yield, daughter corm number and corm yield by 35, 61, 29, 180 and 122 percent, respectively. Also the highest amount of cow manure compared to control increased flower number, fresh flower yield, dried stigma yield and corm yield by 32, 51, 38 and 51 percentages, respectively. Therefore, more flower and corm yield were obtained in 9198 kg.ha^-1 cow manure consumption with 150 corm.m^-2 planting density. Therefore, it seems that the production of saffron is suitable using with organic manure compared with chemical manure. Moreover, saffron planting with high corm density is a solution for improving the yield of saffron in the early years of planting.

Abstract In order to study the response of saffron medicinal plant to planting density and different levels of manure, a two year experiment was conducted in split-plot as complete block design with three replications in 2015-16 and 2016-2017 in Gonabad area. Main factor consisted of 5, 10, and 15 cm plant spacing on row and sub factor was control (no manure application), and application of 0, 20, 40, and 60 t/ha cow manure. Experiment results showed that maximum value of fresh flower yield in first year (127.4 kg/ha) achieved in 60 t/ha and in second year (72.3 kg/ha) obtained from 40 t/ha manure application under 5 cm plant spacing in row. The highest fresh stigma yield in both years (10.300 and 5.383 kg/ha, respectively) was obtained due to high planting density (5 cm plant spacing in row) and 40 t/ha manure application. Also, dry stigma yield under this treatment with 2.300 and 1.770 kg/ha, respectively had more increase in both years than other treatments. The highest daughter corm number in both years (614 and 591 corm/m2, respectively) obtained from highest corm planting density. In first year, 40 t/ha manure treatment had the highest value (592 corm/m2) and in second year, 60 t/ha manure application showed the highest value (572 corm/m2). In first year, the highest corm yield with 22724 kg/ha achieved from 5 cm plant spacing in row and 40 t/ha manure. But, in second year the highest mean value (12429 kg/ha) obtained from the same planting density and use of 60 t/ha manure. Therefore, to achieve suitable economic yield in saffron cultivation, application of 40 t/ha cow manure in 20×5 cm planting density under climatic and edaphic conditions similar to this experiment location is suggested.

Abstract This experiment was conducted to study the effect of soil texture on flower and corm yield of saffron. This experiment was carried out based on Randomized Complete Block Design with four treatments and four replications in box at Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, in 2011. Treatments included of: 1- 100% field soil + cow manure, 2- 70% field soil + 30% sand, 3- 70% field soil + 30% sand + cow manure and 4- 70% sand + 30% field soil + cow manure. Results showed that the effect of soil texture was significant on all flower and corm properties. The highest flower and stigma fresh weight per box (1.59 and 0.10 g, respectively) and petal dry weight (0.12 g) were observed in 70% sand + 30% field soil + cow manure. The highest corm number in 2-3 cm diameter per box was obtained in 70% field soil + 30% sand + cow manure (3.75 numbers). Treatment of 70% sand + 30% field soil + cow manure produced the highest corm number in 3-6 g (1.75 numbers) and 6-9 g (1.25 numbers) per box, but the lowest values of most studied indices were obtained in 100% field soil + cow manure. Generally, our results indicated that light soil texture has more advantages than heavy soil texture in saffron cultivation. Therefore, soil modification through lighter soil application can improve saffron flower and corm yield.