Efecto de dos enmiendas orgánicas y un fertilizante inorgánico sobre algunas variables del suelo y del cultivo de sorgo forrajero (Sorghum vulgare Pers.).

Abstract

Sorghum production at the national level had its highest peak in the years 1989 and 1991 with a production between 700,000 to 800,000 tn, in 1995 it dropped drastically to a production between 100,000 to 170,000 tn, already in 2012 it had a production of 34,915 tn, in 2019 its production was 6,380 tn, this is the latest figure that is known, in 2020A there are no figures according to the FENALCE census. However, in the department of Norte de Santander there are no sorghum production figures available. In Colombia, the crisis between Russia and Ukraine has affected the price increase and supply of fertilizers because Russia was the main supplier of this type of agricultural inputs to Colombia. The main problem at Villa Marina experimental farm is that it does not have pastures that produce enough forage of adequate quality for animal feed. The study was carried out at the Villa Marina Experimental Farm, which is located in the Matajira fraction, Pamplonita Municipal jurisdiction, located at kilometer 49 on the Pamplona-Cúcuta road. A randomized block design with four treatments and three replications was used to evaluate the effect of two organic amendments and an inorganic fertilizer on some soil variables and on the growth and yield of the forage sorghum crop. An experimental area of 150.33 m2 was selected and divided into five blocks of 16 m x 1.61 m and a separation of 0.26 m between blocks. The crop variables evaluated were: plant height, number of leaves on the main stem, number of nodes on the main stem, leaf area index, number of stems per tillers. The measurements were made on days 24, 54 and 84 after sowing (dds) according to the growth stages of the sorghum crop, namely, vegetative stage (0-35 days approximately); reproductive stage (from 35 to 65 days approximately); maturation stage (from 65 to 120 days approximately) and maturity stage (from 65 to 120 days approximately). There was a positive effect of organic fertilizers on soil variables, but it was only significant in soil bulk density. The use of organic fertilizers had a positive impact on most of the crop variables both in green biomass and dry matter, especially the use of Dicomagro fertilizer. Compared to chemical fertilization, the organic fertilizers used in this study can be used as a viable alternative to replace the use of chemical fertilizers. The effect of organic fertilizers on plant growth depends on factors such as the type of fertilizer used, the dose applied, climate and soil conditions. Although organic fertilizers can improve soil quality by increasing its organic matter and nutrient content, resulting in an increase in the number of leaves of the sorghum crop, in this study no statistically significant response was observed, although T2 and T4 presented higher NH than the control. This shows what some studies have demonstrated, that the application of organic fertilizers can increase the number of leaves of the sorghum crop.