Brachiaria decumbens Stapf: Overview
Brachiaria decumbens Stapf, also known as signal grass, is a species of perennial grass belonging to the Poaceae family. This plant is native to tropical Africa and has been introduced to different parts of the world such as South and Central America, Asia, and Australia. It is considered to be one of the most important and widespread grasses in the tropics.
Brachiaria decumbens Stapf: Appearance
Brachiaria decumbens Stapf is a robust, tufted, and stoloniferous plant that can grow up to 60-100 cm tall. It has a relatively short rhizome that helps the plant spread and establish quickly. The leaves are soft and hairy, measuring around 4-8 cm in width and 20-50 cm in length. The inflorescence is a panicle that can grow up to 30 cm in length, featuring spikelets that are green, purplish or light brown in color.
Brachiaria decumbens Stapf: Common Names
Brachiaria decumbens Stapf is known by several common names including signal grass, African signal grass, callide Rhodes grass, and Congo grass. In some countries, such as Colombia, it is known as braquiaria.
Brachiaria decumbens Stapf: Uses
Brachiaria decumbens Stapf is a highly valued forage grass that is used extensively in the tropics. It is known for its ability to produce high yields and its excellent nutritional value for livestock. Due to its high digestibility, it is commonly used to feed cattle, sheep, and goats in grazing systems, silvopasture, and cut-and-carry systems. Brachiaria decumbens Stapf is also used for erosion control, soil improvement, and as an ornamental plant.
Furthermore, Brachiaria decumbens Stapf has shown potential as a bioenergy crop due to its rapid growth, high biomass yield, and its ability to adapt to different soil and climatic conditions. Some studies have also reported its use in phytoremediation, as it has been shown to have the ability to accumulate high levels of heavy metals such as cadmium and nickel.
Light Requirements
Brachiaria decumbens Stapf grows best in full sunlight. It requires at least 6 hours of direct sunlight per day for optimal growth. Partial shade may be tolerated but can cause the plant to grow slower and produce fewer leaves.
Temperature Requirements
Brachiaria decumbens Stapf thrives in warm temperatures between 20°C to 30°C. Temperatures below 15°C can stunt its growth, reduce leaf production, and cause the plant to turn yellow. Freezing temperatures can severe or kill the plant entirely. Therefore, it is best to plant this species in a region with mild, warm temperatures throughout the year.
Soil Requirements
Brachiaria decumbens Stapf prefers fertile and well-drained soils with a pH range of 5.5 to 7.5. It grows best in sandy to loamy soils, but it can adapt to a wide range of soil types, including clay, as long as the soil is well-drained. Operating with a soil that's too wet or has poor drainage can cause poor germination & stunt the growth of the plant.
Cultivation
Brachiaria decumbens Stapf is a warm-season perennial grass that can be grown in tropical and subtropical regions. The plant prefers well-drained soil that is rich in organic matter. The site for planting should be prepared by plowing and harrowing to a fine tilth.
Brachiaria decumbens Stapf is propagated by seed or vegetatively using stem cuttings. Sow seeds at a depth of 1 cm and maintain soil moisture until germination. The optimum temperature for germination is between 20°C to 30°C. Stem cuttings can be planted directly into the soil or in a nursery bed until they develop roots.
Watering Needs
Brachiaria decumbens Stapf requires regular watering to ensure proper growth and development. The plant has moderate drought tolerance and can survive in dry conditions for short periods. Watering should be done deeply but infrequently to avoid waterlogging of the soil. The amount of water required depends on the soil type, climatic conditions, and stage of growth.
Fertilization
Brachiaria decumbens Stapf responds well to fertilization with nitrogen, phosphorus, and potassium. The plant requires a high level of nitrogen to support growth and development. Apply nitrogen fertilizer at the rate of 50 to 100 kg/ha/year. Phosphorus and potassium should be applied at the rate of 20 to 40 kg/ha/year. Fertilizers should be applied in split doses to avoid leaching and to promote uniform growth.
Pruning
Brachiaria decumbens Stapf should be pruned regularly to encourage new growth and maintain plant vigor. Pruning should be done when the plant reaches a height of 30 to 40 cm. The recommended pruning height is 10 to 15 cm above the ground level. Pruning should be done using a sharp cutting instrument to avoid damage to the plant. The pruned plant material can be used as a source of forage for livestock.
Propagation of Brachiaria Decumbens Stapf
Brachiaria decumbens Stapf, commonly called signal grass, is a perennial, tropical grass that is widely cultivated as a forage crop. Propagation of this plant is important to ensure a good yield of forage and maintain the quality of the plant. The plant can be propagated through several methods which include:
Seed Propagation
Seed propagation is the most common method of propagating Brachiaria decumbens Stapf. The seeds are sown in seedbeds and later transplanted to the main field. The seeds are small and should be sown shallowly, around 0.5 to 1 cm deep. The seedlings should be transplanted when they are 6-8 weeks old, and the soil should be well-prepared and fertile. Transplants should be spaced around 50 to 60 cm apart to allow for good growth and development.
Stolon Propagation
The plant can also be propagated through stolons. Stolons are the runners that grow along the surface of the soil from the main plant. These stolons can be separated from the main plant and transplanted to the main field. Stolon propagation is an easy and inexpensive method of propagating Brachiaria decumbens Stapf. The stolons should have a minimum of two nodes and should be planted in the soil at an angle of around 45 degrees, with the node buried in the soil.
Sprig Propagation
Sprig propagation is another method of propagating Brachiaria decumbens Stapf. Sprigs are the above-ground stems of the plant. Cuttings of around 10-15 cm long can be taken from the plant, and these cuttings should have at least one node. The cuttings should be planted in the soil, and the soil should be kept moist until the sprigs start growing. Sprig propagation is a relatively simple method of propagating the plant, and it is also a good way to maintain the desired characteristics of the plant.
Conclusion
Propagation of Brachiaria decumbens Stapf is important for maintaining the crop's quality and yield. The plant can be propagated through seed, stolon, and sprig propagation methods. Each of these methods has its own advantages and disadvantages, and farmers can choose the method that best fits their needs and resources.
Disease and Pest Management for Brachiaria decumbens Stapf Plant
Whilst Brachiaria decumbens Stapf is known for its potential as a pasture and forage crop, it is also susceptible to various diseases and pests that can negatively impact its growth and yield. Implementing effective disease and pest management practices can help minimize crop losses and promote healthier plant growth and development.
Common Diseases of Brachiaria decumbens Stapf
One of the common diseases of Brachiaria decumbens Stapf is leaf blight caused by the fungus Rhizoctonia solani. Symptoms of leaf blight include the appearance of tiny, water-soaked spots on the leaves, which gradually enlarges and eventually develops into a brownish-black color. To manage leaf blight, it is essential to implement crop rotation practices since this fungus can survive in the soil for an extended period.
A bacterial disease known as the soft rot (Erwinia chrysanthemi) can also cause significant damage to the Brachiaria decumbens Stapf plant. This disease manifests itself in the form of a foul odor emanating from the plant accompanied by a soft, watery rotting of the stem and roots. The best way to manage soft rot is to ensure proper monitoring of irrigation practices, as waterlogged soil is a conducive environment for the growth of the bacteria.
Common Pests of Brachiaria decumbens Stapf
Insects such as aphids, mites, armyworms, and nematodes are some of the pests that can cause damage to the Brachiaria decumbens Stapf plant. Armyworms chew on the leaves of the plant, causing shredding and tissue damage. Similarly, nematodes feed on the roots of the plant, leading to stunted plant growth and reduced yield.
One way to manage pests is by introducing biological control methods such as predatory mites and parasitic wasps that feed on harmful insects. Also, the use of chemical insecticides may be effective in controlling insect pests, but it is important to use them judiciously and in compliance with regulatory measures to prevent environmental pollution.
