Tillering of Marandu palisadegrass maintained at fixed or variable heights throughout the year

Abstract

Satisfactory tillering is the basic attribute to ensure stability and productivity of a grass population. We aimed to develop an understanding of tillering in Urochloa brizantha syn. Brachiaria brizantha cv. Marandu (Marandu palisadegrass) maintained at constant or variable heights during the various seasons of the year and to identify defoliation strategies that optimize tillering. In an experiment conducted in Uberlândia, Minas Gerais, Brazil, 3 defoliation strategies were studied: sward kept at 30 cm during the whole year (constant height); kept at 15 cm in fall/winter, 30 cm in spring and 45 cm in summer (increasing height); and kept at 45 cm in fall/winter, 30 cm in spring and 15 cm in the summer (decreasing height). The experiment was completely randomized, with 4 replicates. The following variables were evaluated: tiller appearance (TAR), mortality (TMR) and survival (TSR) rates; the balance (BAL) between TAR and TMR; tiller population stability (TPS); and number of tillers/m 2 (NT). In winter and late spring, TAR and BAL were low, while in early spring, the sward with decreasing height showed high TAR, BAL and TPS. The NT was higher when managed with increasing height than with other height strategies. Lowering pasture height from 45 to 30 cm after the winter increased TAR in early spring. Grazing studies seem warranted to assess how these results can be reproduced under grazing and how pasture yield and quality plus animal performance compare with those under the fixed grazing height regimen.Keywords: Defoliation, grazing management, pasture height, tillers, Urochloa brizantha. ResumenLa capacidad para formar macollas es un atributo básico para garantizar la sostenibilidad y productividad de una población de plantas en una pastura. En Uberlândia, Minas Gerais, Brazil se evaluó el macollamiento de Urochloa brizantha (syn. Brachiaria brizantha) cv. Marandú manejado a alturas constantes o variables durante las diferentes estaciones del año con el objetivo de identificar las estrategias de defoliación que optimicen el macollamiento de este cultivar. Las estrategias de defoliación consistieron en: pastura a una altura de 30 cm a través del año (altura constante); pastura a 15 cm en otoño/invierno, 30 cm en primavera y 45 cm en verano (altura creciente); y pastura a 45 cm en otoño/invierno, 30 cm en primavera y 15 cm en verano (altura decreciente). El diseño del experimento fue completamente al azar, con 4 repeticiones. Las variables evaluadas fueron: tasas de aparición de rebrotes (TAR), mortalidad de rebrotes (TMR) y supervivencia de rebrotes (TSR); equilibrio (BAL) entre TAR y TMR; estabilidad de la población de rebrotes (TPS); y número de rebrotes/m 2 (NT). En invierno y hacia finales de la primavera, TAR y BAL fueron bajos, mientras que a principios de la primavera, el tratamiento decreciente mostró altos TAR, BAL y TPS. El NT fue mayor en el ___________ Correspondence: G.P. Silva, University of São Paulo/ESALQ, Department of Animal Science, Av. Pádua Dias, 11, Agronomia, Piracicaba CEP 13418-90...

Nutritional and metabolic parameters of sheep on deferred pasture with different strategy changes during the dry season

“…The grazing period affected the DM intake, when expressed as percentage of body weight (%BW), the CP intake and the NDF digestibility (P<0.10; Table 2), so that the sheep had higher DM intake (%BW) at the beginning and end of the grazing period, and the CP intake and NDF digestibility were higher at the end of the grazing period (P<0.10; Table 2). At the beginning of the grazing period (winter) it is possible that animals were consuming the upper strata of the pastures, with a greater presence of live leaves, however, with the advance of the dry season, when the climatic conditions were unfavorable to regrowth of the pasture (Table 1), there was a worsening in the quality of deferred pasture, with an increase in dead material Pessoa et al, 2016). In the middle of the grazing period, the animals began to consume the most basal strata of the pasture, with a greater presence of dead material and stem.…”

The genotype does not influence the establishment of elephantgrass (Pennisetum purpureum Schum.)

“…All tillers in the sampling area (0.5 m²) were marked in each evaluation using different colour markers. Responses evaluated were the number of tillers m -1 ; the percentage of tiller appearance [(new tillers in the evaluation x 100) /total number of tillers in the first evaluation]; tillers mortality rate [(total number of dead tillers in the evaluation x 100)/total number of tillers in previous evaluation], equations were proposed by Pessoa et al (2016). The stability index of tiller populations was calculated (percentage of survival/percentage of tillers appearance), as proposed by Bahmani, Thom, Matthew, Hooper, and Lemaire (2003).…”

Contribution of tiller age category to herbage accumulation of Marandu palisadegrass under two fertilization regimes

“…For this reason, in our study, we adopted the seasonal defoliation management of Marandu palisadegrass (15 cm in fall and winter and 30 higher defoliation intensity in fall and winter, compared to spring and summer, is necessary to maximize herbage accumulation (Sbrissia et al, 2020). For this reason, in our study, we adopted the seasonal defoliation management of Marandu palisadegrass (15 cm in fall and winter and 30 cm in spring and summer), necessary to increase tillering in spring (Costa et al, 2016;Pessoa et al, 2016), to improve the sward structure (M. E. R. Santos et al, 2017) and forage production (Terra et al, 2020).…”