Crop yield response to water - Cra

Figure 1 Production trends for pistachios in the principal countries (FAO, 2011).IranTurkeyUSASyria300250Production (1 000 tonne)200150100500198519901995200020052009Quality considerationsPistachio is distinguished by having more quality components than other nut crops. Theseinclude not only the alternate bearing feature that affects nut size but also embryoabortion; nuts that have full size hulls and shells but where the kernels die prematurelyor don’t fill at all. Also, endocarp dehiscence (shell splitting) is required to produce thehighest value nuts. Closed nuts shell at harvest cannot be marketed as snack food, whichis the largest market for pistachios. Another type of fruit that is not commercially viableare early splits; nuts that split well before the onset of normal shell splitting. Not onlyare these nuts worthless but they are prone to fungal disease infection that can lead tothe formation of Aflatoxin. Finally, the percentage removal of filled nuts by mechanicalshaking also impacts harvest yields.the tissue was differentiated. Virtually, all the crop is borne on the preformed growth and this hasimplications for irrigation management.Although pistachios have been cultivated for centuries in countries of the Near East and WestAsia, the industry is relatively young in California compared with the other nut crops grownthere. The California pistachio industry is dominated by one variety, Kerman, and large growersand processors have readily embraced advanced practices, including drip or microsprinklerirrigation. In the main producing countries of the Near East, there is a wide-range of varietiesand irrigation is being introduced, even though much production is still rainfed. Californiapistachio growers were very quick to adopt useful research results on water requirements andthe impact of water stress on yield and crop quality partly because much of the acreage islocated in high water cost and/or low availability areas.PISTACHIO 417