Agriculture
Sajjad Moradi Moghaddam; Hamid-Reza Fallahi; Mohammad. Ali Behdani; Sohrab Mahmoodi
Abstract
The storage conditions of saffron mother corms during the summer dormancy period, including natural and pseudo-dormancy stages, can probably affect the vegetative growth and the production of replacement corms (RC), which has not received enough attention in previous scientific studies. This experiment ...
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The storage conditions of saffron mother corms during the summer dormancy period, including natural and pseudo-dormancy stages, can probably affect the vegetative growth and the production of replacement corms (RC), which has not received enough attention in previous scientific studies. This experiment was carried out as a complete randomized block design with seven treatments and three replicates during the 2019 growing season in Qaen, Iran. Experimental treatments were three types of corm storage inside the soil [corm planting on 5th June (A) with natural soil temperature as control, A + summer irrigation on 5th August, and A + mulch application obtained from wheat residues at the rate of 8 ton.ha-1)] and four types of corm storage outside the soil [corm storage at room (ambient temperature) for three months started from 5th June + corm planting on 5th September (B), corm storage in constant temperature (25 oC and relative humidity of ~40 %) in incubator for three months + B, three months corm storage at variable temperature in incubator (one month in 20, 25 and 20 oC) + B and corm storage in room temperature (up to 5th August) and incubator (up to 5th September) + B. The studied traits were the length, number, and weight of leaves, the number and weight of the total RC, the weight of the main RC, the average weight of RCs, and the number and yield of RCs in different weight groups. The results showed that mulch application caused the highest length and number of leaves (35 cm and 9 No per plant, respectively). Incubation of corms at variable temperatures led to a significant increase in the total weight of RC. In contrast, incubation at constant temperature had most significant effect on the number of RC (2022 corms per m2). The highest and the lowest mean weights of RC were obtained in the mulch application (7.23 g) and incubation at constant temperature (2.22 g), respectively. Plant residue treatment (mulch) decreased the number of small RC (less than 6 g) and increased the number of RC in the weight groups of 9-12 and 12-15 g. Incubation of mother corms at variable temperatures led to an increase in the number and yield of RC weighing more than 15 g. Overall, the treatments of plant residue consumption and storage of mother corms at incubator with variable temperatures, in which 66% and 61% of the RC yield was in groups weighing more than 9 g, respectively, were the best experimental treatments in terms of improving the growth of RC.
Agriculture
Hamid-reza Fallahi; Sohrab Mahmoodi
Abstract
The combined effect of water and nutrient availability is one of the most important factors in corm growth and flowering of saffron. In addition, it seems that applying water in amounts more than conventional amounts in semi-arid areas can be more useful in saffron cultivation. Accordingly, the effects ...
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The combined effect of water and nutrient availability is one of the most important factors in corm growth and flowering of saffron. In addition, it seems that applying water in amounts more than conventional amounts in semi-arid areas can be more useful in saffron cultivation. Accordingly, the effects of irrigation regimes [two and four weeks intervals equal to application of 3600 (conventional irrigation treatment) and 7200 m3.ha-1 (extensive-irrigation treatment) during saffron growth], as well as organic (30 ton.ha-1 cow manure based on soil and manure analysis results) and chemical fertilizers (220, 150 and 100 kg.ha-1 urea, super-phosphate and potassium sulfate, respectively) with a control treatment (no-fertilizer) are studied on some physiological growth indices, corm production and flowering of saffron in this experiment. The experiment was conducted as factorial based on a randomized completely block design with three replications in Sarayan county, Iran, during 2014-2016. Vegetative growth indices were studied during the first growth cycle, while flowering indices were measured during the second growth season. Total biomass has an increasing trend during saffron growth cycle in all treatments. This index was higher in cow manure treatment in both levels of water availability, during the last two growth months. Crop growth rate (CGR) was slow (below 3.9 g.m-2.day-1), rapid (3.9-12 g.m-2.day-1) and intermediate (5.5 g.m-2.day-1) in the early (the first 90 days of growth), middle (90-150 days after growth) and late (150-180 days of growth) growth periods. The highest CGR (12 g.m-2.day-1) was obtained in cow manure treatment and 145 days after the first autumnal irrigation. In all treatments, leaf weight ratio (leaf to total plant weight ratio) has a decreasing trend from two months after the first irrigation until the end of the growth cycle and it is slightly higher in fertilization treatments. Cow manure application increased the corm production and total corms weight per plant by 15 and 13%, respectively, compared with the control treatment. The highest mean weight of replacement corms (6.4 g) was shown in combined treatment of cow manure and two weeks' irrigation intervals. The highest values of flower number (98 flower per m2), flower yield (24.3 g.m-2), style yield (0.56 g.m-2) and dry petal yield (3.7 g.m-2) were obtained in plants that had been treated with cow manure and received water in intervals of 4 weeks. In cow manure fertilizer and control treatments, the highest flower and stigma yield were obtained in irrigation intervals of 4 weeks, while in chemical fertilizer treatment, the highest flower and stigma yield were obtained in 2 week irrigation intervals. Therefore, it seems that application of cow manure combined with consumption of 3600 m3.ha-1 is suitable during the first growth cycle of saffron during which corm density and transpiration area are low.