Forage yield and nutritive value of <i>Arachis</i> spp. genotypes in the Brazilian savanna

Abstract

Forage yield, nutritive value, ground cover and mineral concentration of 10 genotypes of Arachis spp. were evaluated over 3 years in Planaltina, Federal District, Brazil. Experimental plots were arranged in a randomized complete block design with 4 replications. Treatments were 5 genotypes of A. pintoi (accessions 2, 4, 5, 6 and 8), 2 genotypes of A. repens (accessions 1 and 7), 1 hybrid A. pintoi × A. repens (accession 3) and 2 A. pintoi cultivars, BRS Mandobi and Belmonte. All genotypes established well and achieved good ground cover in the first year. Cultivar Belmonte and accessions 2 and 4 produced the highest DM yields (means of 8.8, 8.5 and 8.8 t DM/ha/yr, respectively) throughout, while cv. BRS Mandobi and accession 6 were the worst (5.7 and 5.6 t DM/ha/yr). Most genotypes maintained ground cover above 80% throughout the study but cv. BRS Mandobi plus accessions 6 and 8 had declined to 60% or less by the third year. Mean crude protein concentration overall was 166 g/kg with a range of 154‒182 g/kg among genotypes. There was no major genotypic variation in mineral concentrations, which in all cases were considered marginal to adequate for tropical forage legumes. In conclusion, genotypes 2 and 4 (accessions BRA-039799 and BRA-039187, respectively) of A. pintoi are considered the most promising forage peanut options under the edaphoclimatic conditions of the experimental site. More effort is needed to improve seed set in these accessions to increase adoption by farmers. Their persistence under grazing and impact on production should also be demonstrated.

Keywords: Arachis pintoi, Arachis repens, crude protein, digestibility, minerals.