Instituto de Zootecnia, Rua Heitor Penteado 56, CP 13380-011, Nova Odessa, SP, Brazil.
Faculdade de Zootecnia e Engenharia de Alimentos da Universidade de São Paulo, Rua Duque de Caxias 221,CP 13635-900, Pirassununga, SP, Brazil.
Corresponding author. Email: giacomini@iz.sp.gov.br
Abstract
Changes in sward height of pastures managed by continuous grazing according to climatic seasonality may alter tillering and forage production. In order to evaluate the feasibility of seasonal alteration in sward height of Marandu palisade grass pastures (Brachiaria brizantha (Hochst. ex A.Rich.) R.D. Webster; syn. Urochloa brizantha (A.Rich.) Stapf) under continuous grazing management, we studied two constant sward heights (15 cm and 30 cm), and one height that was initiated at 30 cm, reduced to 15 cm in June (dry and cold season) and returned to 30 cm in December (wet and hot season) (30–15–30 cm). Pastures managed at 30–15–30 cm had a greater tiller appearance rate (22 tillers/100 tillers.30 days) than those maintained at 15 cm and 30 cm (16 and 17 tillers/100 tillers.30 days, respectively). In the 30–15–30 cm pastures, a lower accumulation rate of dead material was observed during the dry and cold season (June–August), which resulted in a higher leaf and lower dead material accumulation rate during the second growth season (wet and hot season, December–January). Planned reduction in sward height during the cold season can be used safely because it permits better seasonal distribution and utilisation of forage production without compromising the stability of Marandu palisade grass pastures.
Additional keywords: forage accumulation, stability index, tiller appearance, tiller population density, Urochloa spp.
CSIRO PUBLISHING
Crop & Pasture Science
https://doi.org/10.1071/CP19156
Received 12 April 2019, accepted 26 November 2019, published online 2 March 2020
