Tropical Grasslands-Forrajes Tropicales

Evaluation of herbaceous legumes for crop-livestock systems in eastern Indonesia

Kendrick Cox — 2025-01-31

The sale of cattle presents a significant opportunity to improve livelihoods for smallholder farmers in eastern Indonesia. An opportunity was identified to grow herbaceous forage legumes either in rotation with, or sown within, staple grain crops (maize, rice) to use surplus soil moisture to produce a feed bank for (mostly penned) cattle and potentially increase nitrogen supply to the grain crops. A series of experiments was conducted on Vertisol, Alfisol and Inceptisol soils in lowland and upland districts of eastern Indonesia to identify legumes from 18 taxa suitable for integrated crop-forage systems. Clitoria ternatea and Centrosema pascuorum were found to have best potential for these systems as they established reliably using local methods, consistently ranked highly for herbage yields 2–4 months after sowing and were relatively easy to harvest. Yields were highest on the Vertisol (greatest number of sites) and Inceptisol soils. Lablab purpureus, Macroptilium bracteatum and Mucuna pruriens also ranked high for yield on Vertisol soils. Clitoria ternatea regrew consistently after cutting and forage removal providing potential for extended forage production as growing conditions allow.

Thermal limits to stoloniferous leaves and root growth in Paspalum notatum, a south American native grass

Áurea Rodrigues Cordeiro — 2025-01-31

In tropical regions the cultivation of African grasses for animal forage is extensive and an ecophysiological alternative is to stimulate the use of native species especially in a scenario of global temperature change. The thermal limits to leaf and root growth in Paspalum notatum a South American native grass were evaluated. Stolon fragments with roots and dry parts removed and the same number of nodes were placed in transparent plastic boxes on moistened filter papers and transferred to chambers at constant temperatures of 15, 20, 25, 30, 35 °C and alternating temperatures of 25/15 °C and 30/20 °C, all in a 12 h photoperiod. Leaf production was evaluated daily for 30 days. Stolon fragments showed leaf growth in all temperatures, except at 15 °C. The thermal range limits were 14.3 °C as base temperature and 39.2°C as ceiling temperature. Results showed that 50 degree days were necessary for 50% of leaf growth by the stolons. The largest leaf area occurred at 25 to 30 °C and the largest specific leaf area was at 25 °C. The optimal temperature for growth was 30 °C with higher root growth at 20 °C and in alternating temperatures. Results indicate that P. notatum has potential to grow in a wide range of temperatures and that the increase of global average temperature should not affect its distribution in its current habitat, presenting promising traits as an option for pastures in all tropical regions.

Effect of single and repeated waterlogging events on tropical forage grasses for cut and carry systems

Rowan W. Smith — 2025-01-31

The introduction of improved forage cultivars has enhanced nutrition and performance of beef cattle in stall feeding cut and carry systems in Vietnam and other Southeast Asian countries. However, the persistence of these forages can be reduced by flooding and waterlogging conditions in low-lying land during the monsoon season. This pot study was established with 5 waterlogging treatments (control, 10-day single, 10-day cycle, 20-day single, and continuous waterlogging) for an 84-day period following establishment to evaluate the waterlogging tolerance of 7 improved grass cultivars. Urochloa humidicola (Rendle) Morrone & Zuloaga, Paspalum atratum Swallen. and Digitaria eriantha Streud. were most tolerant of waterlogging. Tiller number and dry matter production were negatively affected by cycling and continuous waterlogging in less tolerant species Megathyrsus maximus (Jacq.) B.K. Simon & S.W.L. Jacobs, Urochloa hybrid ‘Mulato II’ and Urochloa ruziziensis (R. Germ. and C.M. Evrard) Crins. This information will assist in providing recommendations for smallholder farmers about which species to grow under repeated or continuous waterlogging.

Parámetros fermentativos del ensilaje del pasto guinea (Megathyrsus maximus) cv. BRS Zuri cosechado en diferentes horarios

Rafael Marzall do Amaral — 2025-01-31

This study investigates the influence of harvest time during the day (06:00, 09:00, 12:00, 15:00 y 18:00 hours) on the quality of guinea grass (Megathyrsus maximus) cv. BRS Zuri silage. The pasture was harvested 45 days after the last cut, chopped and stored in PVC microsilos for 45 days. Fresh forage ensilability parameters, as well as fermentative and nutritional parameters of silage were evaluated. The concentration of soluble carbohydrates increased linearly depending on the the harvest time and consequent exposure to solar radiation, with values ranging from 1.07 to 2.07% between 06:00 and 18:00 h, respectively (P=0.001). The lowest values for effluent losses, pH, and N-NH₃ were observed at 15:00 h, with significant linear and quadratic effects (P≤0.05) for the three variables. The harvest time influenced quadratically (P≤0.001) the DM content of the silage, with 17.14 and 22.64% DM at 06:00 h and 15:00 h, respectively. Crude protein content was also influenced by harvest time, with the highest value (13.78%) at 15:00 h and the lowest at 06:00 h (10.37%) (P≤0.05). Under the conditions of the study, harvesting guinea grass cv. BRS Zuri grass in the afternoon resulted in a better-quality silage in terms of its sensorial, fermentative, and nutritional characteristics.