Forage potential of native ecotypes of Paspalum notatum and P. guenoarum

ABSTRACT The Paspalum genus includes several species that are important for livestock in Rio Grande do Sul, such as P. notatum and P. guenoarum, typical of native pastures of the Pampa biome. The aim of this study was to investigate forage production and chemical composition of four ecotypes of these species in relation to the cv. ‘Pensacola’ (P. notatum). Ecotypes of P. guenoarum (Azulão and Baio) and P. notatum (André da Rocha and Bagual) and the cv. ‘Pensacola’ were evaluated for two years, during which four cuts/year were made. The work was carried out under field conditions at the Agronomic Experimental Station of the Federal University of Rio Grande do Sul (30°05’S; 51°39’W), in a completely randomized design. P. guenoarum stood out for higher productivity and greater tolerance to cold; the Azulão ecotype showed more autumn production in relation to the other ecotypes. Crude protein content ranged from 14 (Baio) to 15% (‘Pensacola’); for neutral detergent fiber, the variation was 68 (Azulão) to 71% (‘Pensacola’) and for acid detergent fiber there was a variation of 38 (‘Pensacola’) to 43% (Baio). The data demonstrates the potential of native genotypes for use as cattle feeding in southern Brazil.

摘要：
雀稗属（Paspalum）包含多个对南里奥格兰德州家畜养殖具有重要价值的物种，其中地毯草（P. notatum）与圭诺雀稗（P. guenoarum）为潘帕斯生物群落（Pampa biome）原生牧场的典型物种。本研究旨在探究上述两个物种的4个生态型的饲草产量与化学成分，并以潘萨科拉栽培品种（cv. ‘Pensacola’，地毯草）作为对照。
本试验共评估了圭诺雀稗的2个生态型（Azulão与Baio）、地毯草的2个生态型（André da Rocha与Bagual）以及潘萨科拉栽培品种，试验周期为两年，每年进行4次刈割。试验于南里奥格兰德联邦大学农艺试验站（南纬30°05′，西经51°39′）的田间条件下开展，采用完全随机设计（completely randomized design）。
结果表明，圭诺雀稗的饲草产量更高且耐寒性更强；其中Azulão生态型的秋季饲草产量显著高于其余供试生态型。供试材料的粗蛋白（crude protein）含量介于14%（Baio生态型）至15%（潘萨科拉栽培品种）之间；中性洗涤纤维（neutral detergent fiber）含量为68%（Azulão生态型）至71%（潘萨科拉栽培品种）；酸性洗涤纤维（acid detergent fiber）含量则为38%（潘萨科拉栽培品种）至43%（Baio生态型）。
本研究数据证实，本土基因型具备作为巴南部肉牛饲喂饲草的应用潜力。