بررسي اثر رژيم هاي مختلف آبياري بر روي زود خنداني پسته رقم اوحدي

The effect of irrigation regimes on occurrence of early split of pistachio (Pistacia vera L.) CV. ohadi.

The present study was carried out in Rafsanjan .s suburb pistachio orchards (on ouhadi culiivar) during 2002-2005 growing season for 10 treatments includ ing two irrigation intervals (25days, 45day s) and five irrigation skippings in each irrigation interval. During the growing season , amount of ES , irregular cracked, blank and shell split pistachios was evaluated in experimental plots. Our results indicated that long irrigation interval s and deficit irrigation of pistachio trees in late April until early June increased substantially ES formation , twice compared to regular irrigation plots, at harvest stage . The most of ES pistachios observed in treatm ents that affected by drought stress in early june (T4,T8) amont of 7.7% and 9.6% respectively. There was no special trend in related to created pistachios, but deficit irrigation in july increased the arnont of irregular cracked pistachios. Average percentage of ES, cracked and blank pistachio was increased 2.0 3% , 2.91% and 4.37% in 45 days irrigation interval in compare to 25 days respe ctively, however. about shrank and shell split pistachi os betwe en irrigation interval treatments difference was no significianl. For aflato xin measuring, 120 samples were collected, and pistachio fruits were cla ssified to 3 group s, according to their appearance characteristics, including ES, fruit s having cracking hull, and fruit s with intact hull. Amount of B, and B2 aflatoxin in ES pistachios were 223.4ppb and 25.47ppb (on average ) respectiv ely. In cracked hull fruits aflatoxin B) and B2 were 111.06ppb and 9.71ppb (on average) respectively. Alth ough. the toxin was observed in non of intact hull pistachio fruits . with attention to high level of aflatoxin in ES pistachi os. and that the suitabl e irrigation plays an important role in producing healthy pistachio nuts, we found that proper irrigation management prevents producing ES pistachios and is assnmed as an important step for decreasing of aflatoxin contamination in pistachios at orchard conditions,