African Journal of Ecology and Ecosystems

African Journal of Ecology and Ecosystems ISSN 2756-3367 Vol. 10 (2), pp. 001-015, February, 2023. © International Scholars Journals

Full Length Research Paper

Factors shaping on-farm genetic resources of sorghum (Sorghum bicolor (L.) Moench) in the centre of diversity, Ethiopia

F. Mekbib¹*, A. Bjørnstad¹, L. Sperling² and G. Synnevåg³

¹Norwegian University of Life Sciences, Department of Plant and Environmental Sciences, P. O. Box 5503, N-1432, Aas, Norway.

²International Center for Tropical Agriculture, CIAT, Le Ginestre Lucio Volumnio 37 00178 Rome, Italy.

³Norwegian University of Life Sciences, Department of International and Development Studies, P. O. Box 5003, N-1432, Aas, Norway.

Accepted 12 November, 2022

Abstract

Ethiopia is cited as one of the centres of sorghum diversity. In order to assess the on-farm genetic resources management of sorghum various research methodologies were employed. These were focus group interviews with 360 farmers, key informant interviews with 60 farmers and development agents and semi-structured interviews with 250 farmers. Besides, diversity fair was done with over 1200 farmers. For quantifying on-farm diversity, direct on-farm monitoring and participation with 120 farmers were made. Quantification of varietal diversity per farm was counted by a participatory zigzag sampling in the diagonal direction of the plot with the farmer and all encountered varieties were counted. Soil samples were taken from 120 farms and were subjected to analyses of soil pH, P, available nitrogen, organic matter and exchangeable potassium. Altitude and other related climatic data were collected. The number of varieties conserved by farmers ranged from one to twenty per farm and this is affected by socio-economic and biophysical factors. The mean numbers of 8.3 and 6.3 varieties were grown by Oromo and Amhara farmers respectively. The minimum and maximum range did not vary for both ethnic groups. There was no significant difference in the number of varieties held by various wealth groups. With respect to farm size as explained by the quadratic model, it significantly accounted and predicted for the variation in the number of varieties. The role of soil pH, P, available nitrogen, organic matter, and exchangeable potassium on- farm genetic diversity is described. P was a positive limiting factor for varietal diversity. As to the effect of crop ecology, there were higher number of varieties in the intermediate altitudes than in the lowland and highland. Both the quadratic and linear equation expressed that distance from the house and town and showed non-significant relationship to the number of varieties planted per farm. Varietal mixture is one of the strategies used by the farmers for improved on-farm genetic diversity management. Farmers’ underlying principles for conserving genetic diversity is described. Three models developed, namely; Bioecogeographic genetic diversity model, Farmer induced genetic diversity model and Farmer-cum-bioecogeographic genetic diversity model are explaining the processes shaping on-farm genetic diversity of sorghum in Ethiopia.

Key words: Biophysical factors, farmer varieties, germplasm, genetic diversity, genetic diversity model, socio-economic factors, on-farm.

African Journal of Ecology and Ecosystems ISSN 2756-3367 Vol. 10 (1), pp. 001-010, January, 2023. © International Scholars Journals

Full Length Research Paper

Aspects of ecology and biology of the cichlid, Tilapia mariae from two adjacent low-brackish water lagoons in Nigeria

Soyinka, Olufemi Olukolajo¹* and Ayo-Olalusi², Caroline Ireti²

¹Department of Marine Sciences, University of Lagos, Lagos, Nigeria.

²Nigerian Institute for Oceanography and Marine Research, Victoria Island, Lagos, Nigeria.

Accepted 23 December, 2022

Abstract

Some aspects of the ecology and biology of the spotted tilapia, Tilapia mariae from Badagry and Ologe Lagoons in Nigeria were examined between August 2006 and May 2007. The species was captured throughout the sampling period and constituted about 34.55 and 38.42% of five cichlid species in the catch from Badagry and Ologe Lagoons respectively. Whereas, the total lengths of the specimens from Badagry Lagoon ranged from 8.2 to 17.1 cm (SL, 6.5 – 15.0 cm), specimens from Ologe Lagoon had a total length of 8.9 – 18.1 cm (SL, 6.9 – 13.5 cm). The total weight ranged from 15.50 to 86.50 g and 15.00 to 105.40 g for the specimens from Badagry and Ologe Lagoons respectively. Generally, the condition factors of T. mariae from Badagry Lagoon were higher than those from Ologe lagoon. The sex ratio of 1:0.66 and 1:0.70 were obtained in specimens from Badagry and Ologe Lagoons respectively. Four gonad maturation stages were recorded in Badagry Lagoon, while three were recorded in Ologe Lagoon. Plant materials, diatoms and green algae predominated the food items consumed by the species in Badagry Lagoon, while diatoms, cyanobacteria and green algae were the most abundant items consumed in Ologe Lagoon. Adequate management of the species will enhance fish production in the sub-region.

Key words: Brackish-water, Lagoon, Tilapia mariae, cichlid, food items.

African Journal of Ecology and Ecosystems ISSN: 2756-3367 Vol. 9 (9), pp. 001-008, September, 2022. © International Scholars Journals

Full Length Research Paper

Bioprospecting and characterization of poly-b-hydroxyalkanoate (PHAs) producing bacteria isolated from Colombian sugarcane producing areas

Moreno Nubia*, Gutiérrez Ivonne, Malagón Dionisio, Grosso Victoria, Revelo Dolly, Suárez Diego, González Juan, Aristizábal Fabio, Espinosa Armando and Montoya Dolly

Universidad Nacional de Colombia, Instituto de Biotecnología, Ciudad Universitaria, Edificio Manuel Ancizar, Bogotá, Colombia, AA 14490.

Accepted 26 July, 2022

Bioprospecting for poly-b-hydroxyalkanoate (PHA)-accumulating micro-organisms was carried out in sugarcane growing areas of Colombia. They were isolated in unbalanced culture medium (high carbon/nitrogen ratio) with sucrose, fructose and glucose used as carbon source. PHAs producing bacteria were identified by staining with Sudan black and solubilising cellular components in sodium hypochlorite. A arbitrary scale was established (ranging from 1 to 4) for selecting the best strains, acording to growth, staining with Sudan black and solubilising cellular material. 108 isolates rated higher than 2 were obtained by using this scale; 44 of these were selected for evaluating them in a balloon flask for their ability to grow in sucrose. Scheffe’s test grouped the isolates evaluated in the balloon flask for polymer production and productivity. The 6 best isolates were evaluated in a fermenter to determine their kinetic growth profiles, substrate consumption and polymer accumulation. Differential scanning calorimeter (DSC) was used on the recovered polymer for determining fusion temperature and the conclusion was reached that 2 strains accumulated poly- - hydroxybutyrate (PHB) and another 4 accumulated hydroxy-butyrate copolymers and other monomer units. These 6 strains were molecularly characterised by partially sequencing the 16s rRNA ribosomal gene, localizing them in 4 clusters on the taxonomic tree.

Key words: Biopolymer, PHA, native microorganism, fermentation, microbiology biodiversity.

African Journal of Ecology and Ecosystems ISSN: 2756-3367 Vol. 9 (9), pp. 001-009, September, 2022. © International Scholars Journals

Full Length Research Paper

Genetic diversity and population structure of Ethiopian lentil (Lens culinaris Medikus) landraces as revealed by ISSR marker

Edossa Fikiru¹*, Kassahun Tesfaye² and Endashaw Bekele²

¹Sinana Agricultural Research Center, Bale-Robe, Ethiopia.

²Addis Ababa University, Science Faculty, Department of Biology, Addis Ababa, Ethiopia.

Accepted 4 August, 2022

Abstract

Characterization of genetic resources maintained at genebanks has important implication for future utilization and collection activities. The objective of this study was to assess the level of genetic diversity, genetic structure and genetic distance, and to indirectly estimate the level of gene flow among populations of Ethiopian lentil landraces using intersimple sequence repeat (ISSR) marker. For this purpose, seeds of seventy landrace accessions collected from seven different administrative regions of Ethiopia were obtained from Inistitute of Biodiversity Conservation and grown at Sinana Agricultural Research Center (Bale-Robe, Ethiopia) on-station field plot. DNA was extracted from a bulk leaf sample of fifteen randomly selected seed-raised plants using a triple CTAB extraction technique. ISSR data were generated using four primers. The total genetic diversity ( H_T ), the intrapopulation genetic diversity ( H_S ) and the interpopulation genetic diversity ( D_ST ) were 0.175, 0.095 and 0.079, respectively. High intrapopulation genetic diversity was observed for Gonder, Shewa and Wello populations, while Arsi, Bale, Tigray and Gojam populations showed low intrapopulation diversity. There was high genetic differentiation (G_ST = 0.455) but intermediate gene flow level (Nm = 0.60) among populations. The genetic distance ( D ) between populations ranged from 0.012 – 0.228. Cluster analysis revealed two groups of Ethiopian lentil landrace populations. The results provide important baseline for future germplasm conservation and improvement programs.

Key words: Bulk sampling, gene flow, genetic differentiation, genetic distance, ISSR, genetic diversity and lentil landrace accessions.

African Journal of Ecology and Ecosystems ISSN: 2756-3367 Vol. 9 (8), pp. 001-008, August, 2022. © International Scholars Journals

Full Length Research Paper

Biodiversity of few Indian charophyte taxa based on molecular characterization and construction of phylogenetic tree

Deepika Abrol* and S. K. Bhatnagar

Department of Biotechnology, Bareilly College, Bareilly 243 005 India.

Accepted 28 June, 2022

Abstract

The world charophyte flora suffered reshuffling in the taxonomic status of many taxa on the basis of certain morphological characters. Large numbers of species were reduced to the status of subspecies, variety or forma while some distant species were merged together. In this study, molecular characteristics such as band frequency, RAPD polymorphism, genetic identity index or similarity index, band sharing frequency and genetic distance within and in between Chara and Nitella were evaluated. With the help of scorable bands, range of molecular sizes was recorded in amplified products of 12 charophyte taxa by using five random primers. This investigation requires further elaboration to reach a definite conclusion.

Key words: Chara, Nitella, Charophyta, molecular characterization.