Resumen

ROJAS-ROJAS, Rafael et al. Growth and intensity of necrosis in nine accessions of avocado under conditions of irrigation with saline water. Rev. Mex. Cienc. Agríc [online]. 2012, vol.3, n.5, pp.959-971. ISSN 2007-0934.

The irrigation with saline waters is one of the principal forms of salinization of soils; upon increasing the concentration of salts in the soil, the soil absorption also increases, which reduces the vegetative growth and produces necrosis in sensitive plants like the avocado. The objective of this research was to study the response of growth and the intensity of foliar necrosis in nine avocado accessions belonging to the races, antillana(2) and Mexicana (5), a hybrid (Guatemalan x Mexican) and of Persea nubiegena 1/7 (1), which is a hybrid of P nubigena original. One year old plants were transplanted and grown in a seed bed with sandy loam soil, from November, 2009 to June, 2010 in a greenhouse in Chapingo, Mexico State. A completely random design experiment was implemented using 9 treatments and 15 repetitions. The irrigation was made up of a Steiner Solution, 25% more NaCl, the CE of 3 dS m^-1 and a pH of 5.5. The intensity of leaf necrosis was used to determine the percentage of individual leaves with foliar necrosis. The plants from the Navideño accession showed a better response to the accumulated increase of height (22.86 cm), number of leaves (27.93), increase in stem diameter (1.00 mm) and low percentage of plants with severe necrosis (37%). Fuerte negro, showed a moderate response in the increase of steam diameter (0.55 mm) and accumulation of height (12.62 cm), number of leaves (22.66), but with a high percentage of individual leaves with severe necrosis (64%); Contrary to what was observed in the segregated plants of Hunucma (35%).

Palabras llave : Persea americana Mill.; Cl; stress because of salination; Na; saline toxicity.