Pests and diseases associated with citrus cultivation

Abstract

The word "Citrus" is both a common name, used by the layman and also the name of a genus within the family Rutaceae. When used as a common name, the word citrus may refer to fruits that are taxonomically within the genus proper (such as oranges, lemon, grapefruit) and also to closely related fruits in other genera such as kumquats (Genus: Fortunella) (Redford and Trice, 2011). It is suspected that there are only three true species of citrus, these being the Citrus maxima (Pummelo ), Citrus medica (Citron) and Citrus reticulata (Mandarin) (Redford and Trice, 2011). Natural and artificial hybridization between these three primitive species together with hybridization between the hybrids themselves coupled with a high rate of naturally occurring spontaneous mutations is what gave rise to the huge number of Citrus varieties observed around the world, even if many varieties grown today grow true from seeds (Dugo and Di Giacomo, 2002). It is thought that Citrus knows its origin from the Asian region where India borders with Burma and China (Redford and Trice, 2011). Citrus cultivation has been widespread in Asia since antiquity, and throughout the course of history, it extended to all tropical and sub-tropical regions of both hemispheres where they are grown mainly as fruit trees in exploitation of their vast economic and commercial importance. From its original home in the jungles at the foot of the Himalayan mountain range Citrus cultivation was spread by the Arabs during the seventh or eighth century, through Persia and Egypt, onto the coast of the Mediterranean. The Seville or Bitter Orange (Citrus bigaradia Loisel), was probably the first to attract the attention of the Arabs due to the essential oil which was extracted from the flowers and from the rind of the fruit and of the highly fragrant orange-blossom water, which is extracted by distilling the blossoms and is still so much used today. The introduction of the ordinary commercial orange (Citrus aurantium Lin.) is probably due to the Arabian travellers in the tenth century. The Mandarin-Orange (Citrus deliciosa Ten.) is indigenous to Southern China and the Shaddock (Citrus decumana Murr.) is native to India. The Lemon (Citrus limonum Risso) and the Citron (Citrus medica Lin.) are thought to be indigenous to Persia and their introduction in the Mediterranean region has probably preceded that of the orange (Borg, 1922). [...]