Dry matter yield of rhizoma perennial peanut (Arachis glabrata) harvested at six, nine and 12 weeks at two semiarid sites

Abstract

Rhizoma perennial peanut (RPP) is a forage legume of excellent adaptability and persistence «»nder subtropical and tropical conditions. Four accessions (USDA-TARS 17033,17050, 17052, and 17097, with PI nos. 276233, 262826, 262833, and 262839, respectively) and two cuitivars (Arbrook and Florigraze) of rhizoma perennial peanut (RPP) in Lajas, and two of the accessions (17033 and 17097) and cultivar Florigraze in Juana Díaz, Puerto Rico, were evaluated for dry matter yield (DMY) under irrigation during a full year.The RPPs were evaluated at six-, nine- and 12-wk harvest intervals (HI) in each of the four seasons of the year. At both sites, yield of accession 17033 was highest (P < 0.01) and averaged 35,779 kg DM/ha/yr. In Lajas, yield of accession 17097 was second best with an average of 30,151 kg DM/ ha/yr, yields of the other four RPPs were similar, averaging 25,374 kg DM/haV yr. Cultivar Florigraze, which produced 16% less than accession 17097 in Lajas, had similar productivity in Juana Díaz. On average, the total yields of accessions 17033 and 17097 and cultivar Florigraze declined (P < 0.01) by about 35 and 27% at the two locations, respectively, as HI increased from six to 12 weeks. Season of harvest had a strong influence on the DMY of RPP. At both locations, 69 and 64% of total yields were produced during spring and summer, respectively. Differences in height among RPPs were significant (P < 0.01) at both locations. Height averaged 26.0,17.6, and 18.5 cm for accessions 17033 and 17097 and cultivar Florigraze, respectively. The great adaptability of RPP to the tropical environment, and its high yield when harvested for hay, make it a crop with the potential of becoming one of the most important forages in the tropics.