Spread of Citrus Tristeza Virus and Evaluation of Tolerant Rootstocks in Venezuela

Abstract

Citrus Tristeza Virus (CTV) was detected by ELISA (enzyme-linked immunosorbent assay) in 55% of the citrus trees tested in Aragua, Carabobo, Yaracuy and Zulia States in Venezuela. High infestation with the aphid Toxoptera citricida Kirk was found in all surveyed areas. Several CTV tolerant rootstocks budded with Valencia and Washington navel oranges were compared in two different ecological areas. The following parameters were taken into consideration: foliage, volume, fruit yields, efficiency, yo of juice, OBrix and 01, of acidity. From the preliminary results the most promising rootstocks seems to be Cleopatra mandarin, Volkamer lemon, Swingle citrumelo and Troyer and Carrizo citranges. The selection of a single rootstock would not be feasible due to the different climatic and soil conditions.