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Vigna luteola (Jacq.) Benth. |
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Leguminosae Incorrectly introduced as Vigna marina Merr. from Costa Rica to Australia; V. nilotica (Del.) Hook; V. bukombensis Harms. Dalrymple vigna (Australia), gilibande, goko, masheke, mugulula, indolo, a kwakwa, kavuhivahi, toshimbo shimbo (Zaire). Sparsely hairy, short-lived perennial with a climbing and twining habit, rooting readily from the stems in contact with moist soil. Leaves trifoliate, leaflets ovate-lanceolate, 2.5 to 10 cm long and 1.5 to 5.0 cm broad, sparsely pubescent on both surfaces. Racemes axillary, many-flowered. Flowers yellow, 1.8 to 2.2 cm long. Pods pendant, thin shelled, with waxy margins when dry, up to 5 cm long and 0.5 to 0.6 cm wide. Zero to six, from brown to black in colour, 3 to 4 mm long and 2 to 3 mm wide, (Barnard, 1969) . CPL 21347 was introduced into Australia from Costa Rica by W.W. Bryan and came to be called Dalrymple vigna. Occurs in wet tropical coastal areas of Africa, Central America, West Indies, southern United States and northern Australia (Grisebach, 1963). Summer-growing. It disappeared after two years' grazing at Samford, south-east Queensland (Jones, Davies and Waite, 1967). It is essentially a plant of wet coastal areas. Prefers a rainfall of about 1 250 mm and above, but will give some useful growth down to 900 mm in wet situations. It does not appear to be very specific as to soil requirements, but friable soils allow it to root down readily. It is one of the few legumes which can tolerate saline conditions (Hutton, 1968). It can be spread by seed in dung under favourable conditions of warmth and moisture, but it does not spread readily. Land preparation for establishment Requires a fully cultivated seed bed. Seed is preferably drilled into a well-prepared seed bed. Oversowing into existing pastures is not successful. Seed should be sown at a depth of 1 to 2.5 cm in spring to early summer, at 1 to 2 kg./ha in mixtures and at 3 to 5 kg./ha alone. Seed treatment before planting To break dormancy: a light mechanical scarification will assist germination, but normally no treatment is required. This legume is nonspecific in its Rhizobium requirement and need not be inoculated. However, inoculation with the cowpea type is advisable (the current Australian inoculum is CB756). If the seed requires pelleting to protect the Rhizobium from the treatment for insect control, rock phosphate should be used (Norris, 1967). To deter attacks by bean fly, treat the seed with 13.2 cc of 15 percent dieldrin emulsifiable concentrate per kg. before planting (Jones, 1965). V. luteola requires adequate phosphorus and molybdenum. Use 250 kg./ha molybdenized
superphosphate for establishment. Andrew and Robins (1969a) determined the critical
percentage of phosphorus in the dry matter of the tops at the immediate preflowering
period as 0.25 percent. V. luteola yielded 44 percent of the dry matter at soil dressing
equivalent to 250 kg./ha superphosphate which it produced at its maximum production at 1
350 kg./ha. Compatibility with grasses and other legumes Grows quite well with Paspalum and Setaria species in moist situations. Bailey (1967b) found that 2, 4-D amine caused severe leaf drop; 2, 4-D ethyl ester, moderate leaf drop; and 2, 4-DB and MCPB, slight leaf drop when sprayed on to 10- to 15-leaf stage V. luteola. MCPB spray caused 8.64 percent of leaf reduction; 2, 4-DB, 18.4 percent; 2, 4-D ethyl ester, 26.5 percent; and 2, 4-D amine, 68.7 percent. It nodulates freely and effectively; Jones, Davies and Waite (1967) found that the nitrogen released when it died markedly improved growth of the associated grasses. Did not survive close cutting in northern Australia (Parbery, 1967a) or heavy grazing (Davidson, 1966). Do not graze the young swards heavily. Established plants will stand heavy grazing. Intermittent grazing is preferable to conserve this legume. No record, but in areas to which it is especially adapted accidental fires would be infrequent. Self-fertile; chromosome number 2n = 22. It flowered in 91 days at Kimberley Research Station, Northern Territory, Australia (lat. 15°17'S) . Suitability for hay and silage No record. It is highly regarded as a pasture plant.
On Cunnunurra clay, Parbery (1967a) recorded 17.4 percent crude protein in the dry matter at flowering.
It is an extremely palatable plant; for this reason it must never be heavily grazed. No record. Owing to its indeterminate flowering habit, seed harvest is difficult. Pods are hidden by new growth before they can be picked, and so hand harvesting has been the only method employed to date. The pods shatter, but not as badly as those of siratro. It is usually hand harvested, and no yields appear to have been recorded. There was only one commercial cultivar, 'Dalrymple', which is no longer readily available, but there are other local ecotypes. High palatability; its ability to grow and nodulate in wet soils. Rather short lived; susceptible to frosts and insect attack. Performance. At Utchee
Creek in north Queensland, it has persisted under grazing for five years and is still
spreading and competing with weeds in this high rainfall area (about 3 750 mm). Jones,
Davies and Waite (1967) obtained yields of 5 698 kg./ha in the first year and 10 934
kg./ha in the second year with a mixed Paspalum plicatulum/V. luteola pasture at Samford
in south-eastern Queensland. The legume contributed 43.4 percent of the dry matter and
65.1 percent of the nitrogen in the first year, and 31.1 and 58.7 percent in the second
year. It did not persist into the third year. Barnard (1969); Davidson (1966). Approximately 30°N and S. It is day-neutral in its flowering habits and flowers throughout the year without interruption of its vegetative growth in frost-free situations. Has poor competitive ability in south Queensland. In frost-free, high rainfall areas in north Queensland, it competes well (Davidson, 1966). It is attacked readily by leaf-eating caterpillars (e.g. Prodenia spp.). Bean fly (Melanagromyza phaseoli) will attack young seedlings (Jones, 1965). Optimum, about 20 to 30°C. Ludlow and Wilson (1967) obtained only 12.5 percent of the yield, 33 percent of the relative growth rate and 11 percent of the leaf area at 20°C compared with plants grown at 30°C. It gives quite good late autumn and early summer growth. It is very frost susceptible but regrowth will take place by established plants when warm weather ensues. Tolerance of drought and flooding It has little drought tolerance and does not perform well under dry conditions. It is, however, one of the best legumes for wet conditions and one of the best pioneer plants in such situations. Vigour of seedling, growth and growth rhythm It has very vigorous seedlings . Its rapid early growth is one of its strongest features (Davidson, 1966). It is a very vigorous grower, especially in its first year; thereafter, its performance is variable. Poor. At Kimberley Research Station, it died out in 140 days on Cockatoo sand (Parbery, 1967b). Minimum germination percentage and quality required for sale In Queensland, all Vigna spp. are required to give a minimum of 70 percent germination with a maximum of 10 percent hard seed and 98.8 percent purity. They are germinated at 32°C after chipping the seed coat (Prodonoff, 1968). At Eumundi, in south-eastern Queensland, Australia (lat. 26°S), rainfall about 1 500 mm, it yielded 1 900 kg. DM/ha in its first year the highest of all the legumes testedbut only 375 kg./ha in its second year. At Kimberley Research Station, the best stand yielded only 550 kg./ha of dry matter, but on the upper Adelaide river it yielded 2 000 kg./ha (Parbery, 1967b).
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