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Pistachio orchards in Anar and Rafsanjan areas in Kerman province face various disorders. These disorders have negative impact on pistachio crop yield and have far-reaching economic consequences. In the present study, the effects of yellow leaves, endocarp lesion, little leaf (Ghermezoo) and leaf burn margin were studied technically and economically. This research project was carried out using 286 pistachio orchards in Anar and Rafsanjan areas, various information of which has been collected by Pistachio Research Center since 2010. Analysis of variance and logit regression were used to investigate the factors affecting the disorders and also the effect of the disorders on the quantitative and qualitative performance of the product and its economic consequences. The results showed that in pistachio orchards with little leaf (Ghermezoo), factors such as high crop density, irrigation with fresh water, inadequate distribution of water in the garden, inconsistency of the garden feeding pattern with the amount of available water, use of only cow and sheep manure and the occurrence of low and high-yield years are more common. In contrast, the use of poultry manure, the use of organic and chemical fertilizers every year, soil application of microelements and pruning are characteristic of pistachio orchards without little leaf (Ghermezoo). This disorder has caused the average yield of pistachio orchards to be reduced by 350 kg per hectare per year. In the field of endocarp lesion, the results showed that factors such as Akbari and Koleghoochi cultivars, irrigation with higher volume and especially the sudden entry of water into the garden (higher discharge), increasing EC of irrigation water, covering the entire width of the irrigation strip by pistachio tree and removing water evaporation from the soil surface, cleaning trees, using wind sand and tillering are the characteristics of gardens with this complication. In contrast, light soil texture, Ahmad Aghaei cultivar, uniform distribution of water in the garden, use of organic and chemical fertilizers in the form of manure pits, application of plows and use of excavators to break the hard layers below and remove weeds in the garden pistachios without endocarp lesion are more common. This disorder causes damage equal to 255 kg per hectare per year. Regarding the leaf burn margin, it was found that conditions such as light soil texture, decrease in tree density, increase in drought and increase in ambient temperature, decrease in irrigation frequency in summer, increase in soil salinity, increase in irrigated area of garden that is affected by sunlight, the use of phosphate fertilizers and animal manure, the use of nitrogen fertilizers in hot seasons such as spring and summer are more common in gardens with this disorder. In contrast, the use of nitrogen fertilizer in the fall, the use of potash fertilizers in the form of soloptas in the hot months, the removal of the hard bottom layer using a loader or excavator and the presence of many weeds, except Shoor and Salmeh, in beside the tree in summer, it is a feature of many pistachio orchards that do not have the Leaf burn margin disorder. The damage caused by the leaf margin disorder is estimated about 230 kg per hectare per year. In the field of yellow leaves, the results showed: heavy soil texture, low crop density, low irrigation and heavy irrigation, lack of uniform distribution of water in the garden, use of cattle and phosphate fertilizers, use of sandy soil, the use of gypsum, the presence of weeds in the garden and improper control of pistachio psylla are the characteristics of pistachio orchards with this complication. In contrast, the use of sheep, poultry, potash and nitrogen fertilizers, use every year instead of a few years among organic and chemical fertilizers, use of micro fertilizers in the soil and on the fertilizer pit and pruning, in pistachio orchards without the disorder of yellow leaves is more noticeable. The damage caused by this disorder is estimated about 420 kg per hectare per year.
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