Response of Forage Sorghum to Water Availability in a Typic Quartzipsamment

Abstract

The objective of this work was to determine the factors of soil water availability (FSWA) that result in the highest agronomic performance of irrigated forage sorghum, with no changes in the plants' chemical-bromatological composition. The experiment was conducted at the Montes Claros State University, Janaúba campus, MG, Brazil, in a Typic Quartzipsamment (Neossolo Flúvico Psamítico - Embrapa) with 59 mm of soil water storage capacity in the 0.0-0.3 m layer, under drip irrigation. A randomized block design with four replications and a split-plot arrangement was used, consisting of five FSWA (f0.2 = 0.20; f0.35 = 0.35; f0.5 = 0.50; f0.65 = 0.65, and f0.8 = 0.80) in the plots and two simple forage sorghum hybrids (Volumax® and BRS-655) in the split-plots. The evaluations were based on fortnightly measurements of plant height, plant transversal diameter, number of leaves per plant, leaf area index, relative chlorophyll content, stem diameter, panicle length, dry matter yield, water use efficiency, crude protein, mineral matter, acid detergent fiber, neutral detergent fiber, and lignin. The FSWA of 0.20 and 0.35 increased dry matter yield and plant height of the two evaluated sorghum hybrids. The Volumax hybrid presented more crude protein content and acid detergent fiber. The evaluated FSWA did not change the chemical-bromatological composition of the sorghum hybrids.

Efectos de la fertilización y de diferentes programas de irrigación sobre el comportamiento productivo y los costos de producción del sorgo forrajero (Sorghum bicolor L. Moench)

“…Por otra parte, la aplicación de fertilizante o programas de irrigación no influyeron sobre el contenido proteico del sorgo. AndradeJúnior et al, (2019) no observaron mejoría en el contenido de PB en la planta de sorgo sometidos a diferentes láminas de irrigación al igual que esta investigación. Tampoco Albuquerque et al, (2020) reportaron mejoría en el tenor de PB al fertilizar el cultivo del sorgo forrajero con 90 kg.ha 1 de P 2 O 5 , 20 kg.ha 1 de KCl y 110 kg.ha 1 de N 2 .…”

Sorghum–Grass Intercropping Systems under Varying Planting Densities in a Semi-Arid Region: Focusing on Soil Carbon and Grain Yield in the Conservation Systems

“…Srinivasarao et al [30] and Datta et al (2018) also noticed a correlation between the grain yield of sorghum and rainfall in semi-arid regions. The prolonged water deficit periods reduced sorghum yield, nutrient absorption, photosynthetic efficiency, and stomatal closure [31]. In the condition of 20% (or lower) availability of soil water, the sorghum controls transpiration by reducing leaf area through leaf senescence, with an increase in root length.…”

“…Probably there was high competition for nitrogen and phosphorus in the intercropping system, requiring the application of fertilizer to supply the demand of both plants. Therefore, fertilization is also an important practice to increase sorghum yield, mainly in the intercropping systems [30][31][32][33][34][35][36][37][38][39]. There was an increase of phosphorus in the soil associated with the application of 400 kg ha −1 reactive phosphate and 200 kg ha −1 of formulation 04-30-10 (nitrogen, phosphorus, and potassium).…”

“…Ferraz-Almeida et al [22] testing the decomposition rate of sugarcane, soybean, corn, and brachiaria residues showed that brachiaria presented a low decomposition rate due to the low contents of nitrogen and high contents of lignin, starch, pectin, hemicellulose, and cellulose (all present high proportion of carbon). Crop residues of sorghum also present a high C:N ratio, directly impacting C stabilization and accumulation [30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47]. The high carbon/nitrogen ratio (low N and high C) affects the total soil organic carbon with a higher accumulation of residues on the soil surface reducing mineral N's availability to the plants [20][21][22].…”