Study the effects of organic and chemical fertilizers on replacement corms and flower characteristics of Saffron (Crocus sativus L.)

Abstract

In order to study the effects of organic and chemical fertilizers on replacement cormsand flowercharacteristics of saffron (Crocus sativus L.), an experiment was conducted in a factorial layout based on randomized complete block design with three replications in a farm at Zaveh, Iran in the growing season of 2013-2014 The experimental treatments were all combination of six types of organic fertilizers (Sheep manure (10 t.ha-1), cow manure (30 t.ha-1), vermi compost (6 t.ha-1), hen manure (5 t.ha-1), urban compost (9 t.ha-1) and control and using and not using chemical fertilizer (Nitrogen (100 kg.ha-1)+Phosphate (80 kg.ha-1)). The studied criteria included: total weight of cormper square meter, average number of buds per corm, diameter of corm and number of replacement cormsin each weight categories (0.1-4g,4.1-8g, 8.1-12g,12.1-16g and more than16.1g), number of flowers, fresh weight offlowers,stigmaandstyle dry weight per square meter, and harvest index of stigma. The results showed that the simple and interaction effects of using and not using chemical fertilizers and organic fertilizers on all studied criteria were significant. Control+chemical fertilizer and hen manure+without chemical fertilizer treatments produced the highest and lowest total corm number (228 and 177 corm per in m2), respectively. The highest and lowest total corm weight (1876 and 1623 g.m-2, respectively), average single corm weight (10.94 and 7.75 g.m-2, respectively), average corm diameter (3 and 2.72 cm, respectively) and average number of buds (8 and 1.33 bud per corm, respectively) were obtained in hen manure+without chemical fertilizer and control+chemical fertilizer treatments, respectively. Control+chemical fertilizer produced the highest replacement corms at the weights of 0.1-4 (12.64%) and 4.1-8g (10.31%) categories. The highest percentage of number of replacement corms at 8.1-12 (16.77%), 12.1-16 (18.10%), and more than 16.1g (31.38%) weight categories were shown in the hen manure+ without chemical fertilizer treatment. Hen manure+without chemical fertilizer and control+ chemical fertilizer treatments produced the highest and lowest number of flowers (142 and 56 flower per square meter, respectively), fresh flower weight (50.20 and 17.60 g.m-2, respectively), stigma dry weight (0.405 and 0.169 g.m-2, respectively), style dry weight (0.685and 0.080 g.m-2, respectively), harvest index of stigma (0.0082, 0.0011, respectively), respectively. The results showed that flower yield in the second year was directly affected by the weight of replacement corms which were produced in the first year. Overall, the results of the present study revealed that the application of organic fertilizer compared with chemical fertilizers had superior effect on replacement corms and yield criteria of saffron.

Keywords

• Diameter of corm
• Fresh flower weight
• Stigma dry weight
• Stigma harvest index
• Number of flower