Evaluation of agronomic traits of some Brachiaria cultivars in the temperate low warm region in Japan

Abstract

AbstractTropical grasses with high forage quality and biomass could be grown as annuals in warm subtropical regions as an additional source of feedstock. For sustainable forage production, it is also vital to know the interactions between plant and weed for the selection of promising alternating forage grass. Brachiaria grass has been used as source of high quality forage in the tropics, and this could be developed as a promising forage grass species in this region. Therefore, this study compared the agronomic traits, productivity, and dominance to weeds in six Brachiaria cultivars with two rhodesgrass cultivars in southwestern Kyushu, Japan. This study was evaluated twice from spring to autumn in 2012. Most Brachiaria cultivars grew more vigorously than the two rhodesgrass cultivars during early seedling development in 2012. Except for ‘Llanero’, all Brachiaria cultivars had a higher dry matter yield than the two rhodesgrass cultivars. Notably, ‘Kennedy’ had the highest dry matter yield of 9.5 t ha−1 at the second cutting, resulting from substantial regrowth after the first cutting. However, two Brachiaria cultivars and one rhodesgrass cultivar evaluated in 2014 were not significantly different. Except ‘Llanero’, biomass percentage in all Brachiaria cultivars ranged from 57 to 81% at the first cutting. Subsequently, the value for the second cutting increased more than 90%. There was a significant positive correlation (P < 0.01) between dominance to weeds and growth in the early stage, indicating that the vigorous growth of Brachiaria grasses, during the early stage was superior to that of weeds in their competition. In addition, Brachiaria ruziziensis and Brachiaria decumbens could be introduced as new variety in temperate low warm region, Japan.