Search results for “Altitude

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6 articles

Reproductive Parameters of Three Populations of Oreochromis Niloticus (Linnaeus, 1758) in the Sudano-Guinean Altitude Zone of Cameroon

Mar 2020 DOI 10.14302/issn.2691-6622.ijar-20-3257

In order to contribute to the improvement of aquaculture production, reproductive parameters of three populations of Oreochromis niloticus of Cameroon were studied between March and May 2019 at the research station of Foumban. At this effect, a total of 81 parents (27 males and 51 females with respective weight 124 ± 6g and 144 ± 5​​g) coming from three hydrogeographicals origins (Niger, Sanaga and IRAD Station) were randomly distributed in triplicate in nine concrete tanks of a m² each with a sex ratio of one male for two females (1♂/2♀). Throughout the test, six females carrying eggs in the oral cavity were collected in each population and 45 days after the start of the trial, all the offspring were collected and the adults sacrificed. At the end of experiment, the IRAD population presented highest significant values (p ≤ 0.05) regardless of the performances considered. The values of the gonado-somatic and the gonado-metric characteristics significantly lower (p ≤ 0.05) were obtained in Niger population (GSR = 0.04 ± 0.02, GSI = 0.05 ± 0.03 and GMR=0.19 ± 0.08;GMI= 0.24±0.07). Considering sex, males presented the lowest significant values (p ≤ 0.05) for all the characteristics studied (GSR = 0.04±0.01, GSI = 0.04±0.01 and GMR= 0.23±0.08;GMI= 0.29±0.09).

Computational EPAS1 rSNP Analysis, Transcriptional Factor Binding Sites and High Altitude Sickness or Adaptation

Feb 2016 DOI 10.14302/issn.2326-0793.jpgr-15-889

Purpose The endothetal Per-Arnt-Sim (PAS) domain protein 1 (EPAS1) gene which encodes hypoxia-inducible-factor-2 alpha (HIF2a) is a transcription factor that is involved in the response to hypoxia. EPAS1 has been found to have four (rs56721780, rs6756667, rs7589621, rs1868092) simple nucleotide polymorphisms (SNPs) associated with human disease.These SNPs were computationally examined with respect to changes in potential transcriptional factor binding sites (TFBS) and these changes were discussed in relation to disease and alterations in high altitude adaptation in humans. Methods The JASPAR CORE and ConSite databases were instrumental in identifying the TFBS. The Vector NTI Advance 11.5 computer program was employed in locating all theTFBS in theEPAS1 gene from 1.6 kb upstream of the transcriptional start site to 539 bps past the 3’UTR. The JASPAR CORE database was also involved in computing each nucleotide occurrence (%) within the TFBS. Results The EPAS1 SNPs in the promoter, intron two and the 3’UTR regions have previously been found to be significantly associated with disease and different levels of high-altitude hypoxia among native Tibetans. The SNP alleles were found to alter the DNA landscape for potential transcriptional factors (TFs) to attach resulting in changes in TFBS and thereby, alter which transcriptional factors potentially regulate the EPAS1 genesuch as for the glucocorticoid and mineralocorticoid nuclear receptor binding sites created by the rs7589621 rSNP EPAS1-G allele. These receptors regulate carbohydrate, protein and fat metabolism. Also the minor rs7589621 rSNP EPAS1-A creates a punitive TFBS for the FOXC TF which is an important regulator of cell viability and resistance to oxidative stress. These EPAS1 SNPs should be considered as regulatory (r) SNPs. Conclusion The alleles of each rSNP were found to generate unique TFBS resulting in potential changes in TF EPAS1 regulation. The punitive changes in TFBS created by the four rSNPs could very well influence the significant cline in allele frequencies seen in Tibetans with increasing altitude or the haplotype association with high altitude polycythemia in male Han Chinese. These regulatory changes were discussed with respect to changes in human health that result in disease and sickness.

Agronomy Research Open Access

Soil Fertility Dynamics and Xanthomonas Wilt Incidence in Enset (Ensete Ventricosem) Based Farming at Chencha, Southern Ethiopia

May 2025 DOI 10.14302/issn.2639-3166.jar-25-5495

Enset (Ensete ventricosum) is a vital food security crop cultivated in South and South-western parts of Ethiopia. However, enset production and the farming families have been threatened by Xanthomonas wilt and its spread in the farming system. Thus, this study was conducted to investigate the soil fertility and plant management practices association on the incidence of Enset Xanthomonas wilt. Data on soils fertility and diseases from enset based farming clustered into inner, outer and outfield farm zone were sampled and surveyed. The result indicated that soil chemical properties significantly (p≤0.05) varied from inner to outfield farm zone. Significantly maximum nutrients store revealed in inner enset farm zones. Disease incidence reduced from inner to the outfield enset farm zone. Disease prevalence and disease incidence scored 28.5% and 11.6%, respectively depending on altitude and genotypes. Soil fertility levels in the enset inner and outfield plots were varied purposely to cultivate enset products as kocho, bulla or amicho (cooking type). The variations in soil fertility and Xanthomonas wilt incidence was associated with management practices applied for desired enset products. Therefore, management practices in enset based farming, soil fertility and location of enset planting zones found to be major indicators for disease incidence addressing to device control interventions.

Farming Open Access

Research Achievements of Hot Pepper (Capsicum Species) and it Agro-Ecological Requirements in Ethiopia a Review

Apr 2023 DOI 10.14302/issn.3070-2232.jf-21-3946

Hot pepper is an important spice and vegetable crop in Ethiopia. Its production is constrained by a number of problems among which climatic condition is the primary. The amount rain fail temperature humidity the solanaceous groups of vegetables including hot pepper generally are sensitive to environmental conditions. The amount of rain fall required depends on the altitude of the environment, wind speed sunshine hour, which in turn is influenced by a number of genetic and environmental variables. In the absence of any other production constraints, suitable climatic condition and yield of hot pepper are closely related. Pepper, like other crop produces well when it is grown in good environmental condition. Farmers produce hot pepper in different environment without considering the suitable environment. The yield of hot pepper varies year to year; this indicates that pepper crop need intensive care and management for high return per unit area and also appropriate environmental condition. So in order to produce good hot pepper with the required amount of capsaicinoid content it is butter to grow at temperature range of 17.5-28oc. at low altitude hot environment give high capsaicinoid content and in high altitude / Low humidity and high temperatures will cause abscission of buds, flowers and small fruits.

The Agronomy of Mauka (Mirabilis expansa (Ruíz & Pav.) Standl.) - A Review

Feb 2019 DOI 10.14302/issn.2641-9467.jgrc-19-2619

The Andean region is the centre of origin and domestication of at least 9 species of native root and tuber crops in addition to several species of native potatoes. Within this group, Mauka – also known as Miso or Taso ‒ (Mirabilis expansa Ruíz & Pav.) Standl. ‒ Nyctaginaceae) is one of the least well known, despite having much potential. It is cultivated at high altitudes (2300 to 3500 m a.s.l.) in Ecuador, Peru and Bolivia and is thought to be of pre-Inca origin. Mauka is characterized by its high nutritional value due to substantial levels of protein, calcium and phosphorus, as well as secondary metabolites with nutraceutical properties of varied application. It also has good potential as a forage plant. Based on ethnobotanical knowledge and scientific investigations, this review presents advances in the agronomic understanding of Mauka since its discovery five decades ago in several isolated rural Bolivian communities. The information presented covers both Andean and non-Andean countries. It includes results from journals on natural resources, botany, agronomy, and the congress minutes from botanical, agronomic and phytogenetic resources conferences. Theses on Mauka specifically and on phytogenetic resources in general were also reviewed. Books and manuals were reviewed in the libraries of the International Potato Center, INIAP-Ecuador, INIA-Peru and universities. The plant is described with emphasis on its agronomic traits and according to its propagation forms (seed or vegetative); in terms of its agroecology, phenology, growth dynamics and their indices, crop management, harvest and post-harvest processes. It is concluded that important advances in the understanding of the agronomy of Mauka have been accomplished. Furthermore, the review highlights aspects requiring further research, in order to develop improved production technologies to ensure its future use and conservation.

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