عنوان مقاله [English]
Saffron (Crocus sativus L.) belonging to the family Iridaceae is a perennial plant, that is reproduced by corm . Saffron as a winter plant with low water requirement is the most strategic medicinal plant in arid and semi-arid parts of Iran. It is an important cash crop in Khorasan provinces. Khorsasan provides 97 percent of saffron production in Iran. However, the saffron yield in Iran is lower than the other countries like Spain. Saffron flowering can be mainly affected by mother corm size and organic matter, phosphorus and nitrogen content of soil. Since saffron is a perennial crop, it has been adapted to organic fertilizers and hence animal manure plays an important role in this respect.
The amount of manure used for saffron in Iran varies from 20-80 t.ha-1 cow manure. Also, Animal manures were more effective than chemical fertilizers for increases yield. Hosseini et al. (2004) investigated the effect of urea fertilizer and compound liquid fertilizer on foliar uptake and saffron yield. Their results showed the highest yield obtained from application of compound fertilizer once in March 5 that accounted for 33% increase in yield.
The aim of this study was to investigate the effect of planting method and animal manure and foliar fertilizer on corm properties and yield of saffron.
Material and Methods
This experiment was conducted as a split-split plot experiment based on a -randomized complete block design with three replications at the Research Station of Ferdowsi University of Mashhad, Iran during 2009-2010 and 2010-2011 growing seasons. Experimental factors included: planting bed height as a main factor (Flat, 20 cm and 40 cm), manure as a sub factor (10 and 60 t.ha-1) and Dalfard liquid fertilizer as sub-sub factor (leaf spray). Corm planting was done in September with 15 cm depth. The manure was applied before planting and Dalfard liquid fertilizer sprayed on leaf in early March (2009 and 2010). Combined analysis of variance was done using Minitab ver.15 and the means were compared using Duncan multiple range test in 5% level of probability.
Results and discussion
Combined analysis results revealed that effect of planting bed height, manure and micro fertilizer and their interaction were significant on dry weight, diameter of corm, number of replacement corms and number of flowers during experimental years. The highest dry weight, diameter of corm, number and weight of replacement corms and number of flower was shown in flat planting. Some researchers indicated that the flat planting is the best method for saffron cultivation, however, raised bed planting (25cm) is proper causes of better germination and lower fungus disease. The effect of animal manure with Dalfard fertilizer was significant on dry weight, diameter of corm, number of flower and dry weight of stigma. Application of 10 and 60 t.ha-1 manure had the highest and lowest dry weight, diameter of corm, number of replacement corms and number of flowers, respectively. Different studies showed that use of manure is more effective than chemical fertilizers on yield and other traits of saffron.
Koocheki et al. (2011) showed that the highest number of flower, dry weight of flower, stigma corm was in Dalfard treatment. The highest corm diameter and flower number were obtained in flat bed with 10 t.ha-1 manure and Dalfard application.
Total results showed that saffron yield was significantly affected by combined animal manure and liquid fertilizer. Although, higher application of manure (60 t ha-1) decreased saffron yield because of corm decay. Also, raised bed planting by 20cm height is suggested for saffron cultivation.