Ecology and Epidemiology of Diseases of Nut Crops and Olives Caused by Botryosphaeriaceae Fungi in California and Spain

摘要

Nut fruits, including almond, pistachio, and walnut, as well as olive oil, are essential foods of a healthy Mediterranean diet (Estruch et al. 2013). Beneficial effects of consuming nuts and olives include reduction of metabolic syndrome and a lower risk for cardiovascular disease and type 2 diabetes (Kris-Etherton et al. 2008).Consumers' heightened interest in nutritional aspects of food during recent decades has led to a substantial increase in the worldwide production of almond, pistachio, and walnut. Almond, pistachio, and walnut production worldwide rose from 2,731 to 3,571 metric tons from 2010-11 to 2015-16. During this period, California produced around 45% of pistachio, walnut, and almond crops (Fig. 1A-C); it remains the world leader in almond production. Currently, Spain is ranked as the third almond producer worldwide with 53 metric tons after the U.S.A. and Australia but is ranked first in almond-growing area with 540,000 ha (www.magrama.gob.es). This discrepancy between output and production area is due to fact that most Spanish almond orchards have poor soils,depend on rain for irrigation, and consist of traditional, early-flowering, relatively low-yielding cultivars (Fig. ID). Because almond orchards are more profitable than olive orchards, almond production is increasing, while olive production is stable intraditional olive-growing regions of Spain (D. Bananco, personal communication). The economic and social importance of olive is enormous in Spain,and it is the worldwide leader with more than 2.5 million ha (Fig. 1E-F) and economic value of $2.4 billion (www.magrama.gob.es).