CHLOROPHYLL AND CAROTENOIDS IN YELLOW PASSION FRUIT PLANTS IRRIGATED WITH SALINE WATER ON SOIL WITH BOVINE BIOFERTILIZER

The deleterious effects caused by salt stress result in changes in the physiological and biochemical mechanisms of plants, changing, among others, the levels of chlorophyll and carotenoids, affecting the photosynthetic activity and hence growth, development, production and adaptability to adverse environments. The study aimed to evaluate the effects of irrigation water with increasing salinity levels and the application frequency of biofertilizer on the concentration of the photosynthetic pigments (chlorophyll a, b, total and carotenoids) of the yellow passion fruit. The experiment was designed in a 5 x 4 factorial corresponding to the levels of electrical conductivity (EC) of the irrigation water of 0.5; 1.5; 2.5; 3.5 and 4.5 dS m(-1) and to four frequencies of the application of bovine biofertilizer: no biofertilizer (WB); application of bovine biofertilizer one week before transplanting (1WBT); bio-fertilizer application every 90 days after transplanting (90DAT); and bovine bio-fertilizer applied one week before and every 90 days after transplanting (1WBT+ 90DAT). Increased salinity of irrigation water reduced the photosynthetic efficiency in leaves of yellow passion fruit, being more drastic in the conductivity above 2.5 dS m(-1). The frequency of application of biofertilizer did not influence the photosynthetic pigments content.