EVALUATION OF NEW CITRUS ROOTSTOCKS FOR TAHITI' LIME PRODUCTION IN SOUTHERN FLORIDA

摘要

Two Tahiti' lime (Citrus latifolia Tan.) trials were planted in Miami-Dade County to evaluate the performance of new rootstocks specifically selected for their potential on the highly calcareous limerock soils common to the area. The first trial consisted of two replications of 10-tree plots planted in 1997 with a grower-cooperator. There were 20 rootstocks including various sexual and somatic hybrids plus Rangpur (C. limonia Osb.) for comparison. Yield was measured three times over 2 years and the cumulative results ranged from <20 to nearly 160 lb of fruit per tree. The highest yielding trees were those on Volkamer lemon, Rangpur, C. ambylcarpa, US-801, and US-897. This trial was terminated and removed because of citrus canker. The second trial of52 sexual and somatic hybrid rootstocks was planted in 2001 at the USDA, Subtropical Horticulture Research Station, Miami, with six replications of three-tree plots. Yield and tree size were measured once in 2004 before further data collection was suspended by the appearance of citrus canker. Most trees were about 6 to 7 ft tall and produced from <1 to about 11 lb of fruit per tree. Among the higher yielding trees were those on the commercial standard for comparison, C. macrophylla, some selections ofC. limonia (including Rangpur), several somatic hybrids, and Voikamer lemon. Tree condition and appearance (canopy greenness) were rated as a single variable to express apparent differences in nutritional adaptation to the soil. Trees on macrophylla, US-801, US-812, US-897, several somatic hybrids, the C. limonia selections, Rangpur, rough lemon, and Volkamer lemon were among those with the best ratings.