ARACHIS PINTOI: CHARACTERISTICS, TAXONOMY, HABITAT, DISTRIBUTION, USES - BIOLOGY - 2024

Arachis pintoi is a very popular herbaceous plant that belongs to the Fabaceae family. It is commonly known as forage peanuts or pinto peanuts. It is used as a multipurpose forage, green manure, ornamental soil cover crop, cover crop for fruit trees and to improve soil fertility.

It is a perennial herb native to Brazil. It is characterized by its creeping bearing, the development of stolons that grow up to 1 m, alternate leaves made up of four leaflets that form a green carpet where its small and abundant yellow flowers stand out.

Arachis pintoi is an ornamental hedge species. Source: FroyAgta

It adapts to altitudes up to 1,300 meters above sea level, annual rainfall of 1,300 mm, acid-neutral, loamy-sandy soils with good drainage and content of organic matter. It has high nutritional value.

This plant can be propagated by means of seeds or vegetatively through its stolons. In the case of being by seed, an inoculation with bacteria of the Bradyrhizobium genus that are specific for an effective nodulation that manages to incorporate nitrogen into the soil and the plant is usually incorporated into the soil initially.

characteristics

Appearance

It is a creeping herbaceous plant with stolons and a bare stem. It is very striking for the deep green coverage it offers to the ground and its very pretty little yellow flowers.

Leaves

The leaves of the forage peanut are alternate, formed by four leaflets, the color is intense or dark green and the shape of the leaves is ovate.

Leaves of the forage peanut composed of four leaflets. Source: Harry Rose from South West Rocks, Australia

flowers

Species: Arachis pintoi Krapov. & WC Greg (1994).

Cultivars

In several countries commercial cultivars of Arachis pintoi have been released, such as: yellow (Australia), improver and porvenir peanuts (Costa Rica), perennial forage peanuts (Brazil and Colombia) and pico bonito (Honduras).

Habitat and distribution

This grass is distributed in places where annual rainfall is 1,300 mm, although it grows best in humid tropical places where there is more precipitation and there is no intermediate dry spell. It grows from sea level to 1300 m.

Arachis pintoi can tolerate drought and waterlogging conditions. It grows very well and vigorously under shade, and after a dry period it recovers quickly with abundant watering.

This plant adapts to acid soils that have a high content of aluminum and manganese, with a sandy loam texture, with good drainage, that are moderately fertile and with a large amount of organic matter.

It is widely distributed in Brazil, but it can be found in places like Costa Rica, Bolivia, Ecuador, El Salvador, Nicaragua, Colombia, Venezuela, among others.

Applications

The forage peanut as its name implies, is a species used for animal feed purposes, especially sheep, horses and cattle. Annual production can be up to 12 tons per hectare, and is harvested every 8 to 12 weeks.

However, this production is considered low. To increase its production, it can be sown in association with species of the Brachiaria genus and other grasses such as Andropogon gayanus and Panicum maximum.

Arachis pintoi is associated with other grass crops. Source: Harry Rose from South West Rocks, Australia

Arachis pintoi is a legume that is used for soil improvement, increasing nitrogen content, in pastures and as a cover crop for species such as coffee, citrus, African palm, and banana.

This plant is widely used in parks and gardens as a kind of ornamental cover.

Culture

Spread

To propagate it, the seed pods must be sown at a depth between 2 and 6 cm, taking into account an amount of 10 - 15 kg per hectare.

Subsequently, a flattening of the soil is performed. At this point, it is important that the newly harvested seed be dried at a temperature between 35 and 40 ° C for ten days to break its dormancy.

In a matter of six months and when the growing conditions are optimal, it is possible to completely cover the sown land because this plant spreads quickly thanks to its stolons, which also serve for the vegetative propagation of this plant.

Arachis pintoi forms a beautiful green hedge carpet. Source: Harry Rose from South West Rocks, Australia

Regarding the soil in which it should be cultivated, it is recommended that it be high in organic matter, with an acidic to neutral pH, well drained and preferably sandy loam.

An initial inoculation with specific bacterial strains of the Bradyrhizobium genus is frequently carried out before sowing, in order to establish this symbiosis and increase the nitrogen content in the soil and obtain a better growth of the plant.

In this sense, the specificity of the strain used must be taken into account, since only 48 strains of Bradyrhizobium have been shown to effectively fix nitrogen, despite the fact that with other bacteria there is nodulation.

Fertilization

Forage peanuts do best in soils with low levels of phosphorus, however, if this content is very low, it is recommended to apply phosphorous fertilizers. For the rest, the only correction that is sometimes made is the application of lime.

Irrigation

Normally, forage peanuts do better when irrigation is daily and abundant, but in environmental conditions where the annual rainfall is greater than 1100 mm it can adapt well, even withstand up to four months of dry season.

Weather

This fabacea has the highest growth rate during the warm rainy season, however, it resists up to 4 months of drought. It does not support frost as it loses both leaves and stolons, but in the spring season it produces new shoots.

Plagues and diseases

Generally, rats or mice can cause a phytosanitary problem since they are attracted to this plant. Regarding diseases, it can be attacked by rust (Puccinia arachidis), leaf spot (Mycosphaerella sp.), And by Rhizoctonia sp.

References

1. Purcino, HMA, Festin, PM, Elkan, GH 2000. Identification of effective strains of Bradyrhizobium for Arachis pintoi. Tropical Agriculture 77 (4): 226-231.
2. Tropical seeds. 2019. Arachis pintoi (Pinto Peanut): A legume for use in pastures, soil improvement and conservation, and as cover crop in fruit crops. 12 p. Taken from: tropseeds.com
3. Catalog of Life: Annual Checklist 2019. Details of the species Arachis pintoi Krapov. & WCGreg. Taken from: catalogueoflife.org
4. Tropics. 2019. Arachis pintoi Krapov. & WCGreg. Taken from: tropicos.org
5. Grof, B. 1985. Forage attributes of the perennial groundnut Arachis pintoi in a tropical savanna environment in Colombia. CIAT Tropical Pastures Program. Cali, Colombia. Taken from: cgspace.cgiar.org
6. Factsheet - Arachis pintoi - Tropical Forages. 2019. In: Multipurpose forage species. Taken from: tropicalforages.info