Yield, chemical composition and chlorophyll relative content of Tanzania and Mombaça grasses irrigated and fertilized with nitrogen after corn intercropping

Abstract

-It was evaluated the effect of the absence and of application of three nitrogen doses (50, 100 and 200 kg ha -1 of N) and four harvest times in the winter/spring season (from July to October) on dry mass yield (DMY), on the relative chlorophyll contents (ICF -leaf chlorophyll index) and on the contents of total digestible nutrients (TDN), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and lignin, and their respective correlations on Tanzania and Mombaça grasses after intercrop with corn in distroferric red latosol (Oxisol) soil as well. It was used a random block design, in split-plot with four replicates. The greatest DMY occured with the increase of photoperiod (from August), neverthless responses to nitrogen fertilization over cuts difered among the grasses. In an irrigated crop-livestock integration system under cerrado conditions, it is technically feasible the establishment of Tanzania and Mombaça grass intercroped with corn at sowing or if cover nitrogen fertilization is performed because even in the abscence of nitrogen fertilization, great satisfactory quantity of forage was produced, with average DMY of 2,000 kg ha -1 per cut during the highest shortage of roughage for animals (winter/spring). Nitrogen fertilization after corn harvest increases DMY and improves bromatologic composition of the grasses, as contents of chlorophyll and CP in winter/spring is increased, besides the increase of contents of TDN and a reduction on the contents of NDF and ADF until September. Leaf chlorophyll index can be used to estimate the DMY and CP content and as a marker of the need of nitrogen fertilization of Tanzania and Mombaça grasses submitted to cutting.Key Words: crop-livestock integration, crude protein, Megathyrsus maximum, neutral and acid detergent fiber, no-tillage system, total digestible nutrients Produtividade, composição bromatológica e teor relativo de clorofila dos capins tanzânia e mombaça irrigados e adubados com nitrogênio após o consórcio com milho RESUMO -Avaliou-se o efeito da ausência e da aplicação de três doses de nitrogênio (50, 100 e 200 kg ha -1 de N) e quatro épocas de corte no inverno/primavera (julho a outubro) sobre a produtividade de massa seca (PMS), os teores relativos de clorofila (ICF -índice de clorofila foliar) e os teores de nutrientes digestíveis totais (NDT), proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA) e lignina, bem como suas respectivas correlações nos capins tanzânia e mombaça após o consórcio com milho em um Latossolo Vermelho distroférrico. O delineamento experimental utilizado foi o de blocos casualizados, em parcelas subdivididas, com quatro repetições. As maiores PMS ocorreram com o aumento do fotoperíodo (a partir de agosto), no entanto, as respostas à adubação nitrogenada ao longo dos cortes diferiram entre e dentre os capins. Em sistema de integração lavoura-pecuária irrigado sob condições de cerrado, é tecnicamente viável o estabelecimento dos capins tanzânia e mombaça em consórcio c...

Silage production of corn intercropped with tropical forages in an integrated crop-livestock system with lambs

“…Bernardino & Garcia (2009) reported that LI values below 30% limit the growth of both palisade and signal grasses. That period usually coincides with the critical period of competition for annual grain crops; therefore, if the grass shows rapid emergence and excessive initial growth, the application of a subdose of nicosulfuron is required (Pariz et al, 2011a), as it was done in the present study.…”

“…The vast majority of current studies on grain crops, such as corn, sorghum, and soybean, intercropped with tropical forages in the ICLS conducted in the Brazilian Cerrado do not assess grazing by animals (Crusciol et al, 2011(Crusciol et al, , 2012Mateus et al, 2011;Pariz et al, 2011aPariz et al, , 2011bCosta et al, 2012). Therefore, researches with this approach and specifically with sheep and lambs (Ovis aries) are still essential in this context, since animal grazing with high stocking rates and inadequate management can reduce straw yield, besides affecting soil quality and crop productivity (Carvalho et al, 2010).…”

Autumn Maize Intercropped with Tropical Forages: Crop Residues, Nutrient Cycling, Subsequent Soybean and Soil Quality

“…The highest TDMY and FDMY of Guinea grass cv. Tanzânia sown by broadcasting, on the day of maize sowing (Table 2) was due to the better emergence of this grass in relation to the other sowing methods, as well as to the higher yield potential compared to other forages, given by the better weather conditions of early spring ( Figure 1) (Pariz et al, 2011b). The lowest FDMY of Congo grass, sown in maize stage V4 without incorporation of seeds in the soil, can be explained by the shorter development time and lower plant density, requiring more time for tillering after maize harvest.…”

Straw decomposition of nitrogen-fertilized grasses intercropped with irrigated maize in an integrated crop-livestock system

“…Factors such as these increase the likelihood of failure of fall crops ("safrinha" -second growing season), resulting in fallow agricultural areas during seven months of the year, compromising the success of no-till systems . In this context, integrated crop-livestock systems represent a viable alternative of year-round use of agricultural areas (Pariz et al, 2011).…”