PERFORMANCE EVALUATION OF SORGHUM VARIETY CNIA-INTA UNDER DIFFERENT NITROGEN SOURCES OF SUPPLY

Abstract

Given the importance of sorghum for Nicaraguan small and medium farmers and their use for grain production, the National Agrarian University (UNA), and INTSORMIL Program, since year 2000 have been evaluating sorghum varieties and land races. After three years of results, the good productive variety CNIA-INTA was selected to be evaluated at different low levels of nitrogen fertilization under the practices of the small farmers. An alternative method of fertilization that includes the use of biomass of Vigna radiata L. as source of N was also evaluated. Three trials were established during the second season of 2004. One in Tisma, Department of Masaya, the second at the Experimental research west Center (CEO), located in Posoltega, Department of Chinandega and the third in San Ramón, Matagalpa, in the community of Guadalupe, located 10 km apart from Matagalpa. A randomized completed block design with four replications was used; each plot was shaped by seven rows 5 m. long, separated 0.6 m. between each other. The four central rows were used as main plot to collect information. The analysis of variance showed highly significant differences between localities and treatments for grain yield. A significant interaction was determined between localities x treatment, on grain yield. Concerning grain yield, the whole amount of Urea at planting time (6 078 kg ha -1) and the use of Mungo (5 655 kg ha-1) were statistically equal and both differed from the fractioned urea treatment (4488 kg ha-1).Considering localities, Tisma shows the largest yield with (7,259 kg ha -1), with experimental research west center with the smaller yield (3 932 kg ha-1). There were not differences among treatments concerning weight of thousand grains, but in the case of localities, San Ramon, showed the larger weight (26.7 g). Biomass production was not affected by the way on how nitrogen was distributed. However, when Mungo was applied lightly overcome treatment with chemical fertilizers. The same behavior was obtained for this variable among localities. There was interaction between localities and treatments in the case of grain yield. Tisma, was the locality where Sorghum shows the higher yield. It is interesting that treatment using Mungo reach the higher yield in San Ramón, and the second in the remaining localities studied.

DOI: 10.5377/calera.v10i14.24