ABSTRACT. Current DNA extraction protocols, which require liquid nitrogen, lyophilization and considerable infrastructure in terms of instrumentation, often impede the application of biotechnological tools in less researched crops in laboratories in developing countries. We modified and optimized the existing CTAB method for plant genomic DNA extraction by avoiding liquid nitrogen usage and lyophilization. DNA was extracted directly from freshly harvested leaves ground in pre-heated CTAB buffer. Chloroform:isoamyl alcohol (24:1) and RNase treatments followed by single-purification step decontaminated the samples thereby paving way for selective extraction of DNA. High molecular weight DNA yield in the range of 328 to 4776 ng/µL with an average of 1459 ng/µL was obtained from 45 samples of cultivated and wild Cajanus species. With an absorbance ratio at 260 to 280 nm, a range of 1.66 to 2.20, and a mean of 1.85, very low levels of protein and polysaccharide contamination were recorded. Forty samples can be extracted daily at a cost between 1.8 and US$2.0 per plant sample. This modified method is suitable for most plants especially members of the Leguminosae. Apart from Cajanus, it has been extensively applied in DNA extraction from Cicer and Vigna species.

The morphological and anatomical studies of Benincasa hispida (Thunb.) Cogn. from Nigeria was carried out with the view to reporting morphological and anatomical characteristics for the first time. Physical and microscopic (microtomy) observations were used. B. hispida is a monoecious climbing or trailing herb, stem hairy, 5-angled, with suborbicular stipuliform bract at the petiole-base; leaves simple, very hairy on both surface, alternate, blade palmately or ovate in young plant, base cordate. Flowering occurs between April and May. Female flowers solitary, male flowers solitary or in a slender-pedunculate racemes, petals-5, cream, yellow or pale yellow, ovary ellipsoid, ovules many, stigma 3-lobed and stamen 3. Fruits are large, weighs 8.5 - 9.0 kg, succulent, densely hairy when young, with a thick waxy deposit when mature, cylindrical to oblong with hairy stalk. Seeds are ovate-obovate, cream. Leaves and petals of male flower are amphistomatic with anomocytic, tetracytic and anisocytic stomata while petals of the female flower are hypostomatic with anomocytic stomata only on the abaxial surface. It has glandular and non-glandular trichomes with uniseriate stalk, clavate and multicellular gland heads. The midrib, petiole, stem, tendril, male and female flower stalks and tendril have hollow pith with 3, 9, 6-7, 16, 14 and 10 bicollateral vascular bundles respectively. The percentage crude protein, ash, carbohydrate, lipid, crude fibre, alkaloid, flavonoid, tannin and phytate could account for the numerous medicinal properties.

DNA methylation plays an important role for mammalian development. However, it is unclear whether the DNA methylation pattern is evolutionarily conserved. The Y chromosome serves as a powerful tool for the study of human evolution because it is transferred between males. In this study, based on deep-rooted pedigrees and the latest Y chromosome phylogenetic tree, we performed epigenetic pattern analysis of the Y chromosome from 72 donors. By comparing their respective DNA methylation level, we found that the DNA methylation pattern on the Y chromosome was stable among family members and haplogroups. Interestingly, two haplogroup-specific methylation sites were found, which were both genotype-dependent. Moreover, the African and Asian samples also had similar DNA methylation pattern with a remote divergence time. Our findings indicated that the DNA methylation pattern on the Y chromosome was conservative during human male history.

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The impacts of oil and gas pipeline construction on the forest and biodiversity in parts of the Niger Delta was investigated. This was achieved by studying the construction activities and operational phases of two pipelines with cumulative length of 165 km vis-à-vis the biodiversity of the affected area. The study involved field sampling along the RoWs to inventorize the fauna and flora, visual assessments and interview with locals. It was observed that the pipelines traversed moist lowland/freshwater swamp and mangrove forests, and barrier islands with approximately 4,950,000 m 2 (equivalent of 495 hectares) of forest cleared and 9,642,000 trees killed to realize the pipelines. A total of 219 plant species in 66 families and 125 different fauna species from 64 families were recorded in these areas. Three out of the 4 recorded species of Meliaceae were threatened based on IUCN Conservation Status. Also based on IUCN Conservation Status, 20 mammals, including Pan troglodytes, Cercopithecus erythrogaster and Trichechus senegalensis, 7 birds, 2 reptiles and 1 amphibian were within threatened group. The results showed that the study area had witnessed colossal loss of biodiversity due to habitat displacement, forest fragmentation and deforestation, and escalated exploitation of species. The study identified the most affected biodiversity, and proffered measures to mitigate such occurrences.