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Panicum repens L. |
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Graminae Torpedo grass (United States), cheno (India), limanota (Zambia), creeping panicum (Zimbabwe, Africa), panic rampant, muran (Iraq). A rhizomatous, creeping perennial, rooting at the base, 30-90 cm tall. Leaf-blades usually inrolled when dry, 5-15 cm long and 5-12 mm wide with scattered hairs on the upper surface. Inflorescence an open panicle 6-20 cm long, branches ascending, spikelets 3 mm long, acute and gaping at the tip. Fruit glossy white. Young shoots covered by leaf-sheaths (hence "torpedo grass"). Malaysia, Africa, Sri Lanka, India, Burma, Thailand, United States. Makes its main growth in summer. Sea-level to 1 800 m. Adapted to areas with a winter rainfall, it will not survive hot dry seasons. It tolerates drought, as the rhizomes remain alive in long dry periods. Generally found on sandy soils, but some strains grow on heavy clay. The soils are always wet and of alluvial origin. It is useful on copper-deficient soils. It is aggressive and can be spread by ploughing. It is usually propagated by rhizomes. In India, is sown by seed. Sow on the surface and roll or cover lightly. It is sown in summer at 11 kg/ha in Gujarat, India. Vigour of growth and growth rhythm It is sown at the end of January in Gujarat, flowers in May, and is cut green or allowed to ripen for seed. Resistant to grazing and trampling, but rapidly becomes sod-bound. It will stand heavy stocking, and can be renovated with a deep disc-harrowing when it becomes sod-bound. Dry-matter and green-matter yields It is usually not sown as a pasture, but one farmer in Taiwan claims it will produce 100 tonnes green matter per hectare per year under irrigation when top-dressed with 200 kg urea per hectare after each of five cuts per year (Manidool, personal communication). Yields fall off -after several years under unfavourable drought conditions (Thorp, 1979). At Gujarat, unirrigated, it yielded 2 096 kg green matter per hectare (Srinivasan, Bonde & Tejwani, 1962). At Laguna, Philippines, Furoc and Javier (1976) harvested 62 000 kg green matter per hectare from an irrigated, abandoned rice field. 1 300 kg grain per hectare in India (Solomon, 1953). Its adaptation to wet conditions; its production and palatability when young. It can become a serious weed of arable land and is difficult to eradicate (Thorp, 1979). It is a poor seed producer. The leaves are easily killed by frost. It does not tolerate dense shade. It can invade other pastures and can become a weed along drainage ditches, where it becomes difficult to eradicate (Gilliland et al., 1971). It is extremely palatable and nutritious over a long growing season, but at the mature stage the old leaves tend to become tough (Thorp, 1979) and are neglected by stock. Chemical analysis and digestibility Göhl (1975) quotes analyses by Lim (1968); 28.3 percent dry matter, 24 percent crude protein, 22.6 percent crude fibre, 13.4 percent ash, 2.1 percent ether extract, 37.9 percent nitrogen-free extract in the dry matter of fresh material cut at four weeks in Malaysia. Lake shores, and seasonal and permanent swamps. Panicum repens grows well even after several days in standing water. It is frequent on lake edges, edges of dams and in swamps throughout the tropics (Sayer & Lavieren, 1975). 2n=36, 40, 45 (Fedorov, 1974). Seed production and harvesting Seed production is poor. The ripe crop is cut into sheaves, dried, and the seed beaten out on boards in Gujarat. It is a valuable pasture grass in a number of tropical countries and it provides feed in paddy areas, particularly for draught cattle and buffaloes. It is also cut by hand from roadsides and edges of paddy-fields to feed to dairy cattle. In Iraq it is an important grazing plant for swamp buffaloes. No figures have been cited. It is a useful grass for binding coastal sands and lake shores. It is used to fix mine dumps in Zimbabwe (Chippendall & Crook, 1976). It was also used for stabilizing the steeper slopes of ponds (20-30°) in Zambia where cattle approach to drink water (Verboom & Brunt, 1970). In Gujarat, it proved to have the greatest root-binding capacity of several grasses, but gave poor above- ground yields (Srinivasan, Bonde & Tejwani, 1962).str Very good; it occurs on saline sands in western Zambia (Verboom & Brunt, 1970).
Furoc & Javier, 1976. |