Showing papers on "Corchorus olitorius published in 1990"

Studies on drought susceptibility of corchorus olitorius l. : ii. effects of moisture stress at different physiological stages on vegetative growth and seed yield of c. olitorius cv. 'oniyaya'

Abstract: Concurrent studies reported earlier described the drought susceptibility of two cultivars of Corchorus olitorius during the vegetative stage. The present greenhouse study was a further investigation conducted to evaluate the effects of soil water potential of -6 bar imposed at different physiological stages (the mid-vegetative, flowering, pod formation and pod filling) using the cultivar 'Oniyaya' as the test crop. The objective was to determine the most critical period with regards to susceptibility to water stress in terms of vegetative and reproductive yields and yield components. Leaf area was reduced by moisture stress at all stages of growth. Branch number, stem, lamina, petiole and whole plant fresh and dry weights and seed dry weight were significantly reduced by stress at the three reproductive stages. Pod number was greatly lowered when stress was imposed at flowering and pod formation stages, while pod lengths were significantly reduced by stressing at pod formation stage. The flowering stage appeared to be most critical.

Pathogenicity of meloidogyne incognita on corchorus olitorius

Abstract: Summary Two experiments were carried out to study the pathoBenic effects of Meloidogyne incognita on two cultivars of Corchorus olitorius Plant height, mean number of leaves per plant, mean leaf area, fresh and dry shoot weight and chlorophyll content decreased with increases in initial inoculum levels far both cultivars in the two experiments NPK 15:15:15 was found to improve the tolerance of the plants infected by M incognita by markedly reducing the yield losses compared with plants which received no fertilizer treatment, even at lower inoculum levels lation each plant was cut through at the stem base and both fresh and dry shoot weight were then recordedRoots were uprooted and rated for galls using the 0-5 scheme of Taylor and Sasser (1978) A verage leaf area was determined by the Gunkel and MulIigan (1953)method using the relationship reported by Watson(1937) and Gunkel and MulIigan (1953) to calculate area thus: Corchorus olitorius L, an annual broadIeaf herbaceous and fibrous plant is an important crop in Nigeria where it is grown for the bast fibre and as a leaf vegetable It is susceptible to attack by various nematodes including Helicotylenchus spp, Scutellonema clathricaudatum and Hemicyclophora spp (Caveness, 1967) Meloidogyne spp may be particularly damaging (Quin, 1975) Babatola (1983) described the symptqms af attack as chlorosis, wilting, significant reductions in leaf size and total fresh weight, in addition to the characteristic gall of the roots This paper reports results of pathogenicity studies on C olitorius infected by Meloidogyne incognita (Kofoid et White) Chitw and the effect of NPK 15:15:15 fertilizer on such plants