Determinación de la densidad critica en suelos entisoles y alfisoles, aplicada al cultivo de ají habanero (capsicum chinense jacq)

Abstract

Compaction is considered a major constraint on agricultural production due to adverse conditions that hinder optimal crop development. It is important for the producer to take into account the apparent density with which they are handled, which at the same time serves as a rapid indicator of soil quality; under this background was raised the following research work with the following objectives, to determine the variation of the critical density of chili pepper crop in two soil types, Entisol and Alfisol, extracted from different farms in the province, based on the soil taxonomy map developed by MAGAP (2013). It was directed to extract soil samples in different points of the property, with the help of a shovel, and stored in bags with the respective name of the soil type. In order to subject the plants to different levels of apparent density, soil samples Entisol and Alfisol were sieved to a diameter of 2 mm, and then filled into 60 PVC cylinders with a height of 15 cm and a diameter of 160 mm. Each cylinder was compacted to 5 different density levels (1.1; 1.2; 1.3; 1.4; .1.5 gr.cm-3), preparing 5 repetitions for each treatment. Two chili pepper seeds were deposited for each cylinder, carrying out irrigation by drip system maintaining each experimental unit at field capacity, where different variables were evaluated during the vegetative development of the crop, and at the same time variables of the dynamics of resistance to soil penetration were evaluated with the help of the analog penetrometer, obtaining values before sowing and during the development of the crop. Higher compaction values were observed in Entisol soil, with an average of 2,371 kg.cm-2, due to its high content of silt and clay (44%, 30% respectively) while Alfisoles with an average of 1,874 kg.cm-3, being lower than Entisol, due to its higher percentage of sand (59,7%) and low content of clay and silt, justifying that from treatment 3 (1.3 gr.cm-3) the RPS was 2,071 kg.cm-2, which affected the root development of the crop, this being the critical density in the Habanero pepper crop, due to adverse conditions provided by the soil, obtaining critical results of the variables studied regarding the crop, such as height of plants (82.100 cm), fruit diameter (27,620 mm), fruit length (25,020 mm), plant height (75,95 cm), dry weight of fruit (12,008 gr), fresh weight (26,289 gr), root/canopy ratio (0.372) that expresses the moisture content of the whole green area of the plant (stem, leaves, flowers). The following results reflect that the apparent density is critical in 1.3 gr.cm-3, both in the soils Entisoles, and Alfisoles, demonstrating that higher values of density affect considerably the vegetative development of the crop, reflected in its yield. The resistance to penetration is a fundamental indicator to know the compaction of the soil, and to know the causes that provoke it. The Alfisol soil turned out to have less susceptibility to compaction, and at the same time reflected better physiological results of the crop, due to its Franco-Arenose textural class.