Herbage responses of Tamani and Quênia guineagrasses to grazing intensity

Abstract

New forage cultivars require defoliation studies for recommending proper grazing management. Our objective was to characterize herbage accumulation (HA), plantpart composition and nutritive value of guineagrass [Megathyrsus maximus (Jacq.) B. K. Simon & S. W. L. Jacobs] rotationally stocked under two grazing intensities. The experimental design was a randomized complete block with three replicates of a 2 × 2 factorial arrangement of two guineagrass cultivars ('BRS Quênia' and 'BRS Tamani') and two grazing intensities. Heavy (HGI) and lax (LGI) grazing intensities were imposed as post-grazing stubble heights: 15 and 25 cm for Tamani, and 20 and 35 cm for Quênia, respectively. The experimental period was from -grazing HM was sampled as two strata above the stubble height, each comprising 50% of the sampled height (upper and lower stratum). Total herbage accumulation was similar across years, cultivars, and intensities (16,810 kg DM ha −1 ). Quênia and Tamani had the greatest HA during summer. The leaf proportion was least in the HGI pastures. Under HGI, the lower stratum of both cultivars had the greatest stem proportion and the least nutritive value. The greatest herbage CP concentration and the least NDF, ADF, iNDF and LIG concentrations occurred in the upper stratum. Based on these results, 35 and 55 cm are recommended as target heights for initiation of grazing, and 25 and 35 cm as post-grazing stubble heights for Tamani and Quênia, respectively.

WITHDRAWN: Classification of Megathyrsus maximus Accessions Grown in The Colombian Dry Tropical Forest by Nutritional Assessment during contrasting seasons

“…Several factors such as management, regrowth age, fertilization, cut height, phenological aspects, growth under shade and seasons might have a signi cant effect in the nutritional value of forages (Van Soest, 1982Velásquez et al, 2010, Santiago-Hernández et al, 2016, Silva et al, 2017, Coêlho et al, 2018, Vasconcelos et al, 2019, Schnellmann et al, 2020and Tesk et al, 2020 which affects digestibility in animals (Valente et al, 2010). Variability in structural carbohydrates (NDF, ADF) composition of the M. maximus collection may be in uenced by characteristics related to accession own physiological and metabolic aspects as the conversion e ciency of nitrogen and the rate of owering (Costa et al, 2017) which might generate a wide range of available accessions and could be used in plant breeding programs (Deo et al, 2020) to generate or select materials with the best IVDMD (Barahona & Sánchez-Pinzón, 2005) Protein content reduction during low precipitation periods might be caused by the lack of production of new leaves and tillers during dry season.…”

Forage yield and morphogenesis of Megathyrsus maximus cultivars in Roraimas’s savannas

“…Evaluating several cultivars of M. maximus, Veras et al (2020) found higher yields of GDM for cultivars Mombasa (3,249 kg ha -1 ), Massai (2,979 kg ha -1 ), Tamani (2,718 kg ha -1 ) and Zuri (2,704 kg ha -1 ), compared to cultivar Aruana (1.648 kg ha -1 ). Tesk et al (2020) found no significant differences in the GDM yields of the Kenya (4,345 kg ha -1 ) and Tamani (4,055 kg ha -1 ) cultivars, regardless of the season (spring, summer and autumn) and grazing intensity. Similarly, Valote (2018) did not detect significant variations in the forage yield of cultivars Kenya (3,400 kg ha -1 ) and Zuri (3,165 kg ha -1 ), however this cultivar showed a higher leaf/stem ratio (2.2), compared to that observed in the cultivar Kenya (1.5).…”

The Joint Effect of Grazing Intensity and Soil Factors on Aboveground Net Primary Production in Hulunber Grasslands Meadow Steppe

“…It is a generally held view that there occurs an appropriate system of grazing management that can be used to attain a suitable utilization of the grazed grassland ecosystem [14]. Grassland productivity decline may be caused due to overgrazing [62] and the devastation of the grassland ecosystem functioning, which finally results in grassland degradation [63][64][65]. In the present study conducted at an Inner Mongolian typical steppe ecosystem, grazing reduced the grassland herbage quantity.…”