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Panicum coloratum L. |
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Graminae Coloured Guinea grass (Kenya), small panicum (southern Africa), small buffalo grass (Zimbabwe), Klein grass (United States), keria grass (Kenya). A very variable perennial, from 8-9 to over 100 cm high. Panicle 6- 25 cm long with obtuse or subacute green and purple spikelets 2.5-3 mm long with a small, rounded or abruptly acuminate lower glume. Throughout tropical Africa, introduced to the United States and Australia. Summer. Sea-level to 1 000-2 000 m. It grows in areas with a rainfall in excess of 500 mm. The range is 650-1 700 mm (Russell & Webb, 1976). It occurs chiefly on red and black clay soils in Kenya. Land preparation for establishment It requires a well prepared seed-bed. Sowing methods. Drilling or broadcasting. The best sowing depth is about 1 cm but P. coloratum germinated from a depth of 5 cm in the Sudan (Abd-El-Rahman & El- Monayeri, 1967). Sow in the wet season at 11-16 kg/ha (2-3 kg/ha in Texas). In the Sudan, P. coloratum germinated after only 10 mm of rain, when planted at 1 cm (Abd-El-Rahman & El-Monayeri, 1967). Dry-matter and green-matter yields In the wet zone of Vita Levu, Fiji, Roberts (1970a, b) recorded an average of 4 517 kg/ha of dry matter with 9 percent crude protein over three years. About 400 kg/ha if most of the seed is collected.
a tufted, erect perennial up to 1 m high that spreads by long creeping stems. It is deep rooting and very drought resistant, yet it will grow in heavy, seasonally waterlogged soils. It will thus tolerate a wide range of soil conditions and is suitable for use in low or high rainfall areas. It is palatable to cattle, makes good hay and responds well to nitrogen. It mixes well with legumes. Seed production is generally poor and establishment is usually by root-stock or stem cuttings. It was developed in Botswana from indigenous stock (Thorp, 1979).
introduced as CPI 16796, has good winter growth and produced 5 810 kg DM/ha (1 852 kg leaf) in autumn (14 March - 16 July) in south-eastern Queensland when fertilized with 30 kg P, 75 kg K and 300 kg N/ha. Spring growth was 2 181 kg/ha from 15 August to 30 October. Recovery of nitrogen was 53.9 percent (Ostrowski & Fay, 1979).
used in Texas. Further reading. Roe, 1972; Roe & Williams, 1969. Optimum temperature for growth The mean annual temperature ranges from 17.7 to 21.7°C (Russell & Webb, 1976). Minimum temperature for growth The mean temperature for the coldest month ranges from 5.8-11.8°C (Russell & Webb, 1976). Cv. Kabulabula has good winter growth (Roe, 1972). It is susceptible to frost but usually recovers. 13.5-30.3°N and S (Russell & Webb, 1976).„ Maximum germination and quality required for sale 20 percent germinable seed and 80 percent purity in Queensland. Grassland and open woodland on heavy clay soils. P. coloratum was found to fix 23 kg N/ha in 100 days in southern Texas (Wright, Weaver & Holt, 1976). It responds well to nitrogen. 2n=18, 32, 36, 44, 54 (Fedorov, 1974). It cross- pollinates, with some lines incompatible (Hutchinson & Bashaw, 1964). Seed production and harvesting Seed is matured over a long period, well in excess of 15 days with no peak maturation, and at the end of the period virtually all the seed has been shed. Direct heading yielded only 19 percent of the seed; cutting with a reaper and binder, drying under cover and subsequently threshing gave 42 percent; cutting with reaping hook, drying in the field and threshing gave 49 percent; and collecting seed several times by hand shaking gave 62 percent of possible yield (Roe, 1972). In cv. Kabulabula, the tight envelopment of the caryopsis by the lemma and palea delays germination. This can be overcome by a light mechanical scarification (Strickland, 1978) but scarified seed will not remain viable after laboratory storage of three years whereas unscarified seed stored for three years remained viable and there was still some hardseededness (Roe & Williams, 1969). An introduction from eastern Africa, CPI 14375, close to cv. Kabulabula, tolerated moderate salinity (Evans, 1967b).
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