Edak A. Uyoh

Biotechnology, genetic conservation and sustainable use of bioresources

The loss of Africas forests and bioresources is occurring at an alarming rate, a consequence of increasing population pressure, agricultural land degradation, urbanization and neglect. There is a growing recognition worldwide that conservation and sustainable management of bioresources are pressing priorities in the world today. The choice of conservation methods and techniques depend on the objectives of the particular conservation effort, the breeding system and behaviour of the species in question as well as the available resources including funds, trained personnel, infrastructure and technologies. The use of biotechnological tools and “bioprospecting” will open new vistas in medicine, agriculture, silviculture, horticulture, environment and other important issues. This paper reviews some biotechnological tools that could be harnessed in promoting conservation and sustainable use of bioresources. Key words : Bioresources, genetic conservation, biotechnology. African Journal of Biotechnology Vol. 2 (12), pp. 704-709, December 2003

Flow cytometric analysis of nuclear DNA content, mitotic chromosome number and protein separation by SDS-PAGE in three accessions of African locust bean ( Parkia biglobosa Benth.)

Nuclear DNA of three accessions of Parkia biglobosa collected from three locations in northern Cross River State was investigated using a Patec PA II flow cytometer equipped with an argon ion laser (488 nm), and pictures of mitotic chromosomes were taken using a digital micro-camera (Canon) placed on the eye piece of a binocular microscope at 100X oil immersion. Metaphase chromosome counts of 2n = 22 for accessions A and C and 2n = 24 for accession B, were obtained and through flow cytometry, the three accessions were confirmed to be diploids. The nuclear DNA content and genome size for the accessions were 1.5085, 1.489, and 1.5266 pg (737.7054, 728.121, and 746.5074 Mbp) for accessions A, B, and C, respectively. In another experiment, leaf samples from greenhouse-germinated seeds were analyzed for variation in the banding pattern of the protein by SDS-PAGE in the three accessions. Protein was resolved into three banding groups according to their electrophoretic mobility: slow, medium, and fast, clustering between 100–200, 40–70, and 10–25 kDa, respectively. There was 76% similarity in the banding pattern between the accessions.

Genetic diversity in African nutmeg (Monodora myristica) accessions from South Eastern Nigeria

Twenty-one accessions of African nutmeg ( Monodora myristica Gaertn. Dunal), an endangered spice plant, were collected from the South-East and South-South regions of Nigeria and analyzed for genetic diversity using random amplified polymorphic DNA (RAPD) markers. Twenty-one (21) decamer primers were tested out of which 10 that gave reproducible band patterns were selected for the study. A total of 77 bands were generated, ranging from 3 for OPB17 to 13 for OPT07, and were all polymorphic. The mean polymorphic information content ( PIC ) and genetic diversity ( H e ) were 0.673 and 0.697, respectively, indicating high genetic variation among the accessions. Cluster analysis delineated the accessions into four major groups. The maximum similarity index (0.88) based on Dice coefficient was recorded between AGL-01 and CRS-01 while the least (0.13) was between UGA-02 and EKW 01. The derived data was thus able to determine the extent of molecular variation underlying RAPD size polymorphism. Results obtained from this study proved that RAPD could be successfully used as a molecular tool for diversity study in M. myristica . The distributive pattern of genetic variation of M. myristica accessions provides important baseline data for conservation and improvement strategies for this species. Keywords: African nutmeg, random amplified polymorphic DNA (RAPD), genetic variation, polymorphic information content (PIC), similarity index, Monodora myristica African Journal of Biotechnology , Vol 13(42) 4105-4111

Effect of processing on proximate composition, anti-nutrient status and amino acid content in three accessions of African locust bean (Parkia biglobosa (jacq.) benth

Proximate composition, amino acid levels and anti-nutrient factors (polyphenols, phytic acid and oxalate) in the seeds of Parkia biglobosa were determined at three stages: raw, boiled and fermented. The highest anti-nutrient factor present in the raw state was oxalate, while phytic acid was the least. The amino acid of the raw seeds matched favourably to the World Health Organization reference standard. After processing, boiling increased fat, crude fibre and protein, while it reduced moisture, ash and the anti-nutrient content in 64% of the cases examined. Fermentation reduced ash, crude fibre and carbohydrate in all the accessions. It increased the moisture, fat and protein, while reducing the anti-nutrient factors in 78% of the cases. The high levels of protein, fat and amino acids coupled with the low levels of the anti-nutrients in the boiled and fermented seeds make Parkia a good source of nutrients for humans and livestock.

Intraspecific hybridization in “Egusi” melon, Colocynthis citrullus L.

Intraspecific hybridization in Melon, Colocynthis citrullus L. was carried out in the botanical garden of university of Calabar using three varieties namely “sewere” (S) “barablackedge” (BB) and “barawhite edge” (BW). They were crossed in all possible combinations including their reciprocals. Average percentage fruit set of 18.1 was recorded. Colour of young fruits and colour of mature fruits were each found to be controlled by a single gene pair (monogenic inheritance). Chi-square analysis of the data on inheritance showed a good fit between observed and expected ratios in all the populations. Analysis of variance for some growth characters studied showed that most of the hybrids obtained did not differ significantly from their parents (P >0.05) in leaf length, number of leaves per branch, stem width, vine length at maturity and height at branching. However, hybrid BW X BB was found to have produced significantly (P KEY WORDS: Colocynthis citrullus , Intraspecific Hybridization, Heterosis, Fruit colour inheritance Global Jnl Pure and Applied Sciences Vol.10(4) 2004: 519-523