Performance of Tahiti lime on Poncirus trifoliata var. monstrosa Flying Dragon in four densities

Abstract

Introduction. Tahiti lime trees grafted on Rangpur lime grown in São Paulo State, Brazil, in sub-tropical climatic conditions, have a high level of vigor, poor tolerance to Phytophthora spp. and low productivity. Using Poncirus trifoliata var. monstrosa Flying Dragon rootstock which allows one to obtain dwarfed trees and high yields could solve this problem. Materials and methods. In an experiment set up in November 1994 in Brazil, the tree size, fruit production and quality of Tahiti lime grafted on trifoliate orange Flying Dragon were evaluated at four planting spaces: 4 m × 1 m (2 500 trees$\cdot$ha^-1); 4 m × 1.5 m (1 666 trees$\cdot$ha^-1); 4 m × 2 m (1 250 trees$\cdot$ha^-1) and 4 m × 2.5 m (1 000 trees$\cdot$ha^-1), in a rand- omized block design, with four trees per plot. The cultural practices did not include supple- mentary irrigation. Results. Trees planted in the 4 m × 1 m planting space had greater can- opy diameters (2.75 m) than trees planted with the other planting spaces. Whatever the densities considered, tree height did not differ. Average fruit yield (1998 to 2000) was the greatest on the 4 m × 1 m planting space with 21.6 t$\cdot$ha^-1, significantly differing from the 4 m × 2.5 m planting space with 13.1 t$\cdot$ha^-1. Fruit quality was affected by the plant planting space, but all the production was commercially acceptable. Discussion. The use of a high density planting of Tahiti lime grafted on P. trifoliata var. Flying Dragon would be of com- mercial interest, due to greater yields than trees in traditional cropping systems.