Crescimento de helicônias sob estresse salino.

Abstract

While for several cultures exist literature information on the degree of tolerance to the saline stress, for tropical flowers don't exist indicative related to the salinity of the water or of the soil. Because the lack of results of researches involving salinity with relationship to the cultivation of tropical flowers, mainly helicônias, this work objectives is study the tolerance of the species H. psittacorum x H. spathocircinata cv. Golden Torch; H. rostrata, H. psittacorum cv. Suriname Sassy; H. latispatha Benth Red-Yellow Gyro (Orange); H. psittacorum cv. Red Opal and H. x nickeriensis at different irrigation water salinity leveis (0,3, 0,8, 1,3, 1,8, 2,3 and 2,8 dS m"1) in the rhizomes viability and growth, determining the criticai leveis for each one. The experiment was led at the greenhouse of the Federal University of Campina Grande, PB. The treatments were resulting of the factorial combination between the six salinity leveis and the six heliconia species, resulting in the factorial outline 6x 6 with with randomized blocks experimental design. The irrigation waters were prepared for the addition of NaCI. The amount of NaCl used in the preparation of the irrigation waters was determined in way obtaining the electric conductivity of the respective saline levei. Considering the results, it was verified that the salinity of irrigation water didn't interfere in the rhizomes viability and shoot emission of heliconia species. The plant heights were influenced significantly by the irrigation water salinity and for the factor heliconia. Among the heliconia genotypes, TAP varied between 8,49 and 7,32 g. According to the regression studies, the influence of the salinity on TAP demonstrated a linear decreasing. With the increase of the water occurs CEa linear decrease of the biomass variables. The average consumption of water, decreased with increasing CEa irrigation. Irrigation with water of salinity above 0.8 dS m"1, negatively affected the issue of leaves. the number of tillers and growth in height, with greater reduction in heliconia H6 (Nickeriensis). The leveis of salinity of irrigation water up to 0.8 dS m"1 were criticai for the growth of genotypes of H. psittacorum x H. spathocircinata cv. Golden Torch and H. x nickeriensis, because from this levei began to be affected and the leveis above 1.3 dS m"1 were criticai for the growth of other genotypes of helicônias. The H. x nickeriensis presented the lowest values for the variables in comparison to other helicônias evaluated, the genotype is more susceptible to salinity of irrigation water.