Uso de condicionadores e desenvolvimento de sorgo forrageiro em argissolo amarelo irrigado com água salina

Abstract

In modern agriculture, soil conditioners are often used to improve conditions for crop development. In order to evaluate the effect of limestone, plaster and hydrogel conditioners on the development of sorghum in yellow argisol irrigated with saline water, an experiment wascarried out in pots under greenhouse conditions. Two doses of hydrogel, two sources of water, and four combinations of limestone and plaster were used (0% and 0% / 0% and 100% / 50% and 50% / and 100% and 0% of the calcium requirement, to address soil deficiency). A factorial scheme (2x2x4) with 4 repetitions was used, resulting in 16 treatments and 64 experimental units. Sorghum Forrageiro CV was used. BRS Ponta Negra that was carried out during two cuts, the first at 70 days after sowing and the second at 30 days after the first cut. In the first cut, height, number of leaves, dry matter was measured. And the contents of calcium, magnesium, sodium, potassium, copper, iron, manganese and zinc. In the second cut, height, number of leaves and dry matter were measured. In relation to the data analysis, analysis of variance was performed, tukey test at the level of 5%, correlation matrix and principal component analysis, where biplot graphs were generated, which helped in the discussion of the data. The proved to be promising in the gain of dry matter both in isolation and in combination with the other factors and showed capacity to retain nutrients. The different sources of irrigation water were significant, however the one that resulted in the highest dry matter gain was the one that showed the highest electrical conductivity (2.96 dS / m), attributed to the culture's tolerance to salinity. The combinations of limestone and plaster were not significant in any of the treatments in isolation, only being significant in conjunction with the other factors. The application of hydrogel alone was able to increase the productivity of sorghum in a yellow argisol.