Nutrient balance in the soil and nutritive characteristics of maize silage cut at different heights

Abstract

Maize harvesting for silage promotes intense use of soil nutrients. The increase in forage harvesting time can ease nutrient use and benefit the nutritional quality of the silage. However, this practice may be economically unviable due to the reduction in the volume of harvested forage. The objective of our experiment was to evaluate several agronomic parameters, such as production, plant composition, nutritional value of silage and nutrient balance in the soil by harvesting the maize plant at different silage heights: 0.20; 0.40; 0.60; 0.80 and 1.00 m above the ground. The experimental design was completely randomized, with five treatments with five repetitions. Representative plants in each plot were cut and fragmented in a forage machine. This material was homogenized and ensiled in experimental polyvinyl chloride (PVC) silos. Each 0.10 m increase at harvest provided an increase of 0.65% in the dry matter content of the forage and reduced harvest to 339 kg ha -1 of dry matter. The presence of grains in the forage increased linearly 1.24% for every 0.10 m at the time of harvest. The levels of neutral detergent fiber, acid detergent fiber and silage lignin had a linear decrease of 4.5, 2.8 and 9.6%, respectively, per each 0.10 m lift crop height. Regarding the total digestible nutrients, dry matter intake and the relative forage, these values had a linear increase of 0.5, 7.2 and 8.2%, respectively. For each 0.10 m increase in cutting height, there was a decrease in soil nutrients, namely 3.6 kg ha -1 N, 1.3 kg ha -1 P 2 O 5 , 9.5 kg ha -1 K 2 O, 0.9 kg ha -1 CaO and 1.2 kg ha -1 MgO. Even with the harvest at 1.00 m above the ground, nutrient recycling nutrients by necromass is not sufficient to balance the potassium balance in the soil, causing a decline of 37.69 kg ha -1 K 2 O. The maize harvest to 0.47 m height represented the best relationship between silage quantity and quality, being the height that presents the greatest potential for economic return, and can fund management practices and soil fertilization to prevent degradation in foraging systems, mainly to overcome the negative balance of potassium in the system. ResumoA colheita de milho para ensilagem promove intensa exportação de nutrientes do solo. A elevação da altura de colheita da forragem pode amenizar a exportação de nutrientes e beneficiar a qualidade nutricional da silagem. No entanto, essa prática pode ser inviável economicamente devido à redução no volume de forragem colhida. Objetivou-se com este experimento avaliar os parâmetros agronômicos de produção, composição vegetal, valor nutricional da silagem e balanço de nutrientes no solo pela colheita da planta de milho em diferentes alturas: 0,20; 0,40; 0,60; 0,80 e 1,00 m do solo. O delineamento experimental foi inteiramente casualizado, composto por 5 tratamentos com 5 repetições. Plantas representativas de cada parcela foram colhidas nas respectivas alturas e fragmentadas em uma ensiladeira. Este material foi homogeneizado e ensilado em silos experimentais de policloreto de vini...

Meta-analysis of corn plants, green fodder (ensilage), and silages of different types of maize hybrids used in experimental conditions in Brazil

“…Despite the differences in plant height, there was no variation (P = 0.3611) with relation to the height of the spikes. However, the measurement of the insertion height of the spikes is of fundamental importance to determine the cutting height so as to increase the energy quality of the silage as well as the amount of residual OM (Hülse et al, 2017). This is because an increase in the cutting height from 15 to 45 cm from the soil provides a higher starch content and a lower fiber content in corn silage, which increases the digestible DM harvest per hectare (Lynch, Baah, & Beauchemin, 2015).…”

Effect of raising the cutting height in corn on performance and carcass traits of lambs

“…The cutting height at the time of harvest can also improve these intrinsic characteristics of the corn plant, this procedure promotes improvements in the nutritional value of the silage, reducing by 1.9, 0.6 and 1.3% the levels of neutral detergent fiber (NDF), acid detergent fiber (ADF) and hemicellulose (HEM), respectively for every 10 centimeters the cutting height is raised (3) .…”