Cultivo do sorgo submetido ao estresse salino e turno de rega.

Abstract

Crop productivity is strongly influenced by the characteristics of the cultivar used and the edaphoclimatic conditions of each region. The Brazilian semiarid region is characterized by a deficient water balance and extensive areas of soils with excess salts and sodium, requiring research to minimize these effects on crops. In this context, this study evaluated the effect of saline stress and irrigation intervals on growth and physiological parameters of sorghum crops in the conditions of Pombal, PB. The experiment was conducted at the Center for Agri-Food Science and Technology (UFCG) under lysimeter conditions, using a randomized block design in a 5 x 2 factorial scheme, with four replications. It assessed forage sorghum subjected to two levels of electrical conductivity of irrigation water (S1= 0.3 and S2= 8.0 dS m-1) and five irrigation intervals (T1 = daily irrigation, T2 = irrigation every 2 days, T3 = irrigation every 3 days, T4 = irrigation every 4 days, and T5 = irrigation every 5 days). Among the variables analyzed, in the biometric evaluations it was observed that salinity had a significant effect on all growth variables, both in interaction with irrigation interval and as an isolated effect, reducing plant development with increasing salinity. In terms of gas exchange variables, plant development varied depending on the interaction (salinity x irrigation interval). However, it is expected that the results of this research will serve as parameters for improving sorghum cultivation, especially in the Brazilian semiarid region.