Genetic Improvement of Persian Walnut (Juglans regia L.) in Iran

摘要

Persian walnut (Juglans regia L.) is one of main nut crops in Iran. This species together with pistachio and almond have an area above 800;000 ha. Considering the area, pistachio is the most important, while for production walnut is the first nut crop. The walnut improvement program in Iran started early in the 1980s. The main goals of the program could be classified in: 1) release of new cultivar(s) and; 2) resolving difficulties of vegetative propagation. The program started in 1983 with selectionof superior genotypes from orchards and establishing four collections with their progeny (three halfsib progeny from each selection) in Karaj, Shahrood, Mashhad and Urumieh. In 1994, seven genotypes from the Karaj collection were selected and propagatedby grafting. They have been planted together with eight foreign commercial cultivars for advanced studies in Karaj. Two of seven promised genotypes, 'Jamal' and 'Damavad', with reciprocal flowering, were released as the first Iranian cultivars in 2010. Among the foreign cultivars, 'Chandler', 'Pedro' and 'Hartley' showed a good performance and 'Ronde de Montignac' and 'Franquette' were suitable pollenizers in the conditions like Karaj. The selections from other stations, were propagated and planted in Karaj, Kerman and Hamedan in a replicated trial in 2005, which are under evaluation now. Another set of five promising genotypes selected from hybrids made in 1996 are propagated for multilocation evaluation. The second stage of selection of superior genotypes was done again among walnut orchards in the first decade of 2000. The evaluation had been done in 12 provinces and in each 5-10 superior genotypes had been selected. Sixty of these genotypes are propagated and planted for further evaluation in Karaj in 2009. Studies for determining the appropriate methods and time of propagation were practiced. In this case, several experiments had been done to determine the details for a successful patch budding, hot cable and epicotyl grafting.