Cotyledon persistence and seedling growth in fluted Pumpkin (Telfairia occidentalis Hook. F.)

Photosynthetic activity of exposed cotyledons of Telfairia occidentalis during seed germination and the growth of seedlings with removed or attached cotyledons were investigated. The experiment  investigated how early cotyledon removal affects seedling growth. Seedlings from seeds germinated in light and those  germinated in the dark were compared four weeks after germination. The effects of removal of cotyledons on seedling growth were also investigated with  cotyledons removed at different times and from different seed sizes in order to assess the effect of time of removal and seed sizes on seedling growth. Biomass accumulation of the different plant parts, number of leaves and root/shoot ratio were used to assess the relative importance of cotyledon photosynthesis and  cotyledon storage reserves to seedling growth. The cotyledons which are predominantly for storage were found to have a minimal photosynthetic function. Telfairia seedling biomass was significantly reduced (P<0.05) by removal of the cotyledon. Seed size and morphotype influenced the effect of cotyledon removal on seedling growth. The time of cotyledon removal affected all growth parameters negatively with greatest effect on removal at the first week of growth. Cotyledon reserves  support seedling growth of Telfairia occidentalis, and ability to cope with loss of cotyledon is affected by factors such as seed size, morphotype and time of  removal.Keywords: Storage reserves, cotyledon removal, hypogeal, morphotype, Telfairia occidentalis

Effect of growth regulators and explant types on callus induction in Telfairia occidentalis Hook F

Different concentrations of growth regulators and three types of explants were investigated for their efficiency on callus induction in Telfairia occidentalis with a view of providing baseline information for the development of a callus initiation protocol. Three concentrations of kinetin (KN) (0.1, 3.3 and 5.0 mg/L) in combination with two concentrations of 2,4-dichlorophenoxy acetic acid (2,4-D) (2.0 and 5.0 mg/L) and two concentrations of naphthalene acetic acid (NAA) (0.25 and 0.5 mg/L) in combination with 0.25 mg/L benzyl adenine (BA) were tested for their effect on callus induction from stem, leaf and nodal explants collected from field-grown Telfairia plants. Media supplemented with 2,4-D in combination with kinetin gave the highest cumulative percent callus induction. With regards to cumulative percentage callus induction and total callus produced, media supplemented with BA alone was better than media supplemented with kinetin alone.  Irrespective of the growth regulator type, percent callus induction was not significantly different among explant types. The study concluded that, 2,4-D is a better auxin for high callus induction in T. occidentalis explants as compared to NAA. However, there is still a need to test the effect of 2,4-D in combination with BA on callus induction.Keywords: Telfairia occidentalis, callus initiation, 2,4-D, BA, kinetinAfrican Journal of Biotechnology, Vol 13(20), 2015-202

Determination of aquifer units using vertical electrical sounding technique: a case study of federal low cost housing estate, Okeho, SW Nigeria

The groundwater development of Federal Low Cost Housing Estate Okeho involved the use of schlumberger vertical electrical sounding technique. The result of the survey showed that qualitatively three major curve types H, QH and KH were observed. The geoelectric layers range from 3 to 4 while the quantitative interpretation resulted in deducing layer parameters of 190-1103Ώm and 0.70-1.10m for the topsoil. The intermediate layer has layer resistivity of 93 -1590Ώm and thickness of 0.9-4.70m while the weathered basement has resistivity and thickness of 18-50Ώm and 6.0-10.4m. The bedrock resistivity range from 426-6284Ώm with an infinite thickness; the bedrock resistivity of less than 1000Ώm in this area and the weathered layer constitute the aquifer. Keywords: aquifer occurrences, geoelectric parameters, sounding curves Nigeria Journal of Pure and Applied Physics Vol. 4(1) 2005: 60-6

LAXATIVE ACTIVITIES OF CASSIA PODS SOURCED FROM NIGERIA

Detailed biological evaluation for laxative properties using established literature methods with white albino rats, was carried out on the infusions of the pods of the following Cassia species, growing in Nigeria: Cassia alata L., C. hirsuta L., C. occidentalis L., C. podocarpa Guill. Et Perr., C. siamea Lam. and C. sieberiana L. (Family Caesalpinoidae) with Cassia acutifolia Del. (Senna) pod tablet and leaf as reference standards. Of all the Cassia species investigated, a dose-dependent relationship was observed when the infusions of the pods of C. fistula, C. podocarpa, C. acutifolia and also leaf of C. acutifolia were tested at a dose-range of 100mg/kg to 700mg/kg of rat with the presence of wet faeces as an indication of laxation. Indeed, statistically analysis of variance as well as using percentage senna-pod action showed that the laxative potencies of the three Cassia species were not significantly different. Hence, C. fistula and C. podocarpa pods obtained from plants cultivated in Nigeria, can in fact substitute for the official senna pod/tablets. Key Words: Cassia species; laxative activities; relative senna equivalent. Nig. J. Nat Prod. And Med. Vol.3 1999: 51-5

Physiological response of the three most cultivated pepper species (Capsicum spp.) in Africa to drought stress imposed at three stages of growth and development

Drought and excess water are divergent weather conditions, predicted to strongly affect the physiology of plants. The present study investigated the effects of varying drought stress imposed at different stages of growth and development on the three most cultivated Capsicum species in Africa. This was with a view to elucidating the physiological and biochemical responses of these plants to aftermath of drought and to further ascertain the most critical stage of drought in them. Capsicum spp. were exposed to four drought regimes by withholding water to 80-85%, 55-60%, 40-45% and 30-35% water holding capacity (WHC) respectively representing control, light, moderate and severe drought stress conditions. Results showed that moderate and severe drought induced significant reduction in leaf relative water content (LRWC), relative growth rate (RGR), carotenoid, chlorophyll "a", "b" and total chlorophyll content of the study plants at the vegetative stage, particularly in Capsicum chinense. C. chinense exposed to severe drought stress had highest LAR and leaf weight ratio (LWR) at flowering and fruiting stages. Furthermore, C. chinense under moderate and severe drought treatment had higher phenol content at vegetative stage. Irrespective of the growth stage, no pinch of capsaicin content was detected in C. annum. Capsaicin content of C. chinense exposed to drought stress at vegetative stage was significantly lower (p < 0.05) than those exposed to the same drought stress at fruiting stage. The present findings revealed that Capsicum chinense was more tolerant to drought stress than the other two species. Data presented in this study suggest that the three-capsicum species are likely to be more susceptible to the aftermath of drought at the vegetative stage than at either the fruiting or the flowering stage