[Seed production of Arachis pintoi cv. Mani Forrajero Perenne associated with maize and beans]

The establishment and seed production of Arachis pintoi cv. Mani Forrajero Perenne, in association with maize or beans, was studied in a sandy loam Andosol of El Porvenir farm (rain forest, 1,300 m.a.s.l., and 2,700 mm rainfall) in Armenia, Colombia. A randomized complete block experiment design was used with three replications. Plots were 9 m x 4 m. Useful sample area for maize and beans was 18 m(2) and for Mani Forrajero, 3 m(2). Treatments used were: (1) sole-cropped A. pintoi cv. Mani Forrajero Perenne; (2) sole-cropped maize; (3) sole-cropped beans; (4) Mani Forrajero Perenne associated with beans; and (5) Mani Forrajero Perenne associated with maize. There were a total of 15 experimental units (plots), spaced at 1 m both between and within blocks. In the associated systems, planting densities were 20 kg/ha for Mani Forrajero Perenne, 80 kg/ha for beans ICA-Caucaya, and 25 kg/ha for maize ICA V-305. Fertilizers were preplant incorporated in Mani Forrajero at the following rates: 1 t/ha of dolomitic lime (600 kg/ha Ca), 240 kg/ha Mg, 40 kg/ha P, and 80 kg/ha K. Fertilizers, once mixed, were placed at the bottom of the furrow and manually covered before planting. In monocrop systems, Mani Forrajero and beans were planted in furrows spaced at 0.5 m, and maize in furrows spaced at 1 m. In the associated system, Mani Forrajero and beans were planted at 0.25 cm, in alternate double furrows (0.5 m between two rows of the same crop). In the Mani Forrajero-maize system, Mani Forrajero was planted at 0.5 m and maize at 1 m between furrows. Weed control was manual until the crops covered more than 80 percent of the soil. Mani Forrajero was harvested manually 1 year after planting. Vegetative material was removed and a 10-cm layer of soil was collected and passed through a sieve. The seed obtained was washed and sun-dried to a 10 percent moisture content. Beans, due to their exuberant initial growth, invaded the associated Mani Forrajero. This initially caused a change in growth habit of Mani Forrajero, which presented etiolation and fewer green leaves than in monoculture. However, once the beans reached harvest maturity, Mani Forrajero showed a quick recovery. The association Mani Forrajero-maize had an excellent establishment. Mani Forrajero quickly established itself, developing stolons up to 35 cm long in the 3 months following planting, whereas, at this same age in the monocrop, stolons had only reached a length of 20 cm. Seed yield of Mani Forrajero was high, whether in monoculture (6.3 t/ha) or in association with beans (5.4 t/ha) or maize (5.2 t/ha). In the three planting systems, 100-seed weight was 18.8 g, and seed purity, 98 percent. Mani Forrajero did not affect the yields of the associated crops.