Perennial Arachis spp. as a Multipurpose Living Mulch, Ground Cover and Forage

Abstract

ABSTRACT From 1997 to 1999, 16 cultivars/accessions of perennial forage Arachis sp. were evaluated at the Tropical Research and Education Center. IFAS, Homestead, FL. Evaluation focused on adaptability to soil and climatic conditions of south Florida and included criteria deemed desirable for a multipurpose cover crop that might be used as a living mulch in no-till vegetable production fields and orchards, forage for animal feeding, and ornamental ground cover along highway ramps and sidewalks. Four cultivars/accessions of Pinto's peanut, A. pintoi Krapov. & W.C. Gregory, plus IRFL 6968 grew well in the low-fertility calcareous soils with minimal fertilizer, minimal irrigation and no pesticide. They were compared with ‘Florigraze’ rhizoma peanut (A. glabrata Benth.) in all the evaluation criteria used. The stands had become well established 31 months after planting. Biomass yields for the selected accessions at 31 months ranged from 12.0 to 21.5 mt ha−1. Nitrogen content in the dry biomass of plant parts was: 1.8 to 2.2% in below ground growth; 1.4 to 2.1 % in stolons; 2.2 to 3.4% in green leaflets; and 2.1 to 2.4% in senescing leaves. Crude protein (CP) content of plant parts followed this pattern and was highest (17.6 to 22.8%) in green leaflets. Plant tissue carbon content did not vary much between plant fractions nor between accessions, ranging from 37.8% (senescing leaves of IRFL 7154) to 45.4% ('Florigraze' below ground growth). Hemicellulose content of green leaflets varied from 12.8% in ‘Amarillo’ to 27.2% in IRFL 6961. Hemicellulose in the stems and stolons ranged from 16.5% in IRFL 6968 to 25.8% in ‘Amarillo’. These plant tissue properties reflect favorable perennial Arachis characteristics for use as living mulches, forages, and ornamentals in south Florida. The wide differences in morphological and biochemical properties among accessions suggest that major genetic differences exist in the available germplasm, which should permit breeding and release of cultivars with many desirable characteristics.