estimation of the number of aphids carrying citrus tristeza virus that visit adult citrus trees. | aphid species were counted on citrus trees in orchards in valencia, spain, in the spring and autumn of 1997, 1998 and 1999. moericke yellow water traps, the 'sticky shoot' method and counts of established colonies were used in extensive surveys in which 29,502 aphids were recorded and identified. aphis spiraecola and aphis gossypii were the most abundant aphid species. the numbers of aphid species landing on mature trees of grapefruit, sweet orange, lemon and clementine and satsuma mandarins, we ... | 2004 | 15036840 |