Crescimento e produção de genótipos de algodoeiro em solo salino-sódico.

Abstract

We studied the growth and yield of six cultivars and one lineage of cotton (Gossypium hirsutum L), developed in a greenhouse of DEAg/CCT/UFPB, municipal district of Campina Grande - PB, using material whith a loamy-sand, soil texture, previonsly classified as saline sodic soil. The experiment was set in the period of MAy to November 1998. We used the factorial scheme 6 x 5, in completely randomized desiign with three replications. Cultivars and lineage used were: CNPA Precoce 1, CNPA Precoce 2, CNPA 7H, EMBRAPA 113-Algodao. 7MH, EMBRAPA 112-Algodao.6M e CNPA Acala 93/15; and water irrigation salinity levels: 2,0; 4,0; 6,0; 8,0 e 10,0 ds/m a 25 °C, repectively. The control of the irrigation was done by the weighing of the vases, elevating the soil water content to 90% field capacity. The following variables were analysed: plant height, leaf and branch number, leaf area, vegetal matter weight, fiber number and matter weight, yield fiber weight, 100 seeds weight, fiber percentage, plume and CEes weight. The results obtained of this survey showed that the cotton is mores sensitive to salinity in the growth and vegetative development variables than the yield variable between the cultivars and lineage, the CNPA Precoce 2 cultivar has a tendecy to be more perceptible to the salt stresses. While EMBRAPA 113-Algodao.7MH cultivar is more tolerant to water irrigation salinity in growth and vegetative development variables, the CNPA Acala 93/15 lineage is tolerant in yield. The branch and root matter weight were the most affected variables between the cultivars and lineage. There was not influence of 10dS.m1 irrigation waters salinity level on 100 seeds weight and in fiber percentage of the cultivars and lineage but EMBRAPA 112-Algodao.6M cultivar. This cultivar did not adapt to the conditions of the experiment, being the most affected by salinity.