224 research outputs found
Socioeconomics of the Production and Marketing of Haricot Beans (Phaseolus vulgaris L.) in the Western Highlands of Cameroon
There has been an increase in the demand for Haricot beans (Phaseolus vulgaris L.) in Cameroon, most especially from buyers of neighbouring countries and institutions that feed their members. This indicates the existence of opportunities for farmers to exploit the market system and effectively participate in the supply chain within and across national borders. However, farmers don’t make use of this opportunity resulting from multiple constraints ranging from low production levels, low income and inconsistency in market participation to high transaction cost. It is thus relevant to identify and address the constraints facing these farmers in a bid to improve production and market participation. This analyzes the factors influencing farmer’s participation in the production and marketing of haricot beans in the Western Highlands of Cameroon. Data was collected from 200 farmers in 24 villages in the Western Highlands of Cameroon and analyzed using descriptive and inferential statistical techniques. Findings indicate that the production and marketing of beans was dominated by older and married farmers with low educational background who depend on these for their livelihood. In addition, the farming system practiced, production season, seed type planted and access to production resources significantly influence the quantities produced and marketed. To enhance haricot beans production and marketing, the study opines that development interventions lay emphasis on infrastructural and technology improvement especially with regards to the provision and use of improved farm inputs. Keywords: Haricot beans, production, marketing, Western Highlands, Cameroo
Moult of overwintering Wood Warblers <i>Phylloscopus sibilatrix</i> in an annual-cycle perspective
Wood Warblers, an Afro-Palearctic migrant species, are declining steadily in Europe likely due to mortality outside their breeding grounds. However, little is known about their overwintering, and records about the sensitive life-cycle stage of moult in Africa are practically absent. To fill this gap, we report on moult of Wood Warblers captured over two winters (January–February) in 2019–2020 in Cameroon. We caught 14 individuals, of which 12 were monitored for flight feather moult. All inspected individuals showed advanced stages of flight feather renewal. Despite low sample sizes, Underhill-Zucchini moult models aptly explained variation in primary and secondary moult (R2 = 0.61). Estimated moult onset date was 26 December, completion date was 25 February, and moult duration was 61 days. These findings fit well with experimental data on the annual cycle and the timing of recently published migration tracks of Wood Warblers. Jointly, the data suggest that moult timing is set by an internal programme, which enables Wood Warblers to organise their multi-stage migration such that they reach suitable moulting habitat in time, and can depart in time with a fresh plumage for the breeding grounds. In our study, moult occurred during the peak of the dry season, which in Cameroon nonetheless shows high relative humidity. During our mist-netting on 28 cocoa plantations of varying shade cover, Wood Warblers were caught on 6 farms whose canopies were comparatively open. These data suggest that the birds encounter in Cameroon relatively stable climatic conditions for moult, and do not measurably prefer closed-canopy forests. Our findings are important, because successful moult increases survival prospects and because moult needs to be safely embedded in a migratory life cycle. Hence, information on moult timing and location is essential for identifying year-round vulnerabilities of Wood Warblers.<br/
Seeking a disability lens within climate change migration discourses, policies and practices
Around 15% of the global population is estimated to live
with disability. With the Millennium Development Goals
failing to recognise disability issues, the Sustainable
Development Goals seek to promote a stronger focus on
the alleviation of poverty and inequality amongst disabled people. Since then, the vulnerability of disabled people has been highlighted within international climate change agreements. Yet a critical disability lens is largely lacking from broader aspects of climate change adaptation planning. Focusing primarily on examples from the Asia-Pacific region (a region including low-lying coastal areas and islands that are frequently highlighted as exemplars of communities on the front line of climate change), this article discusses the need to integrate critical insights from disability studies into current understandings of climate change adaptation and mobility if we are to facilitate more inclusive, democratic and equitable adaptation in the face of climate change
Neural network design and feature selection using principal component analysis and Taguchi method for identifying wood veneer defects
Nowadays, ensuring high quality can be considered the main strength for a company’s success. Especially, in a period of economic recession, quality control is crucial from the operational and strategic point of view. There are different quality control methods and it has been proven that on the whole companies using a continuous improvement approach, eliminating waste and maximizing productive flow, are more efficient and produce more with lower costs. This paper presents a method to optimize the quality control stage for a wood manufacturing firm. The method is based on the employment of the principal component analysis in order to reduce the number of critical variables to be given as input for an artificial neural network (ANN) to identify wood veneer defects. The proposed method allows the ANN classifier to identify defects in real time and increase the response speed during the quality control stage so that veneers with defects do not pass through the whole production cycle but are rejected at the beginning
Agrobacterium-Mediated Transformation of Subterranean Clover (Trifolium subterraneum L.)
Major haplotype divergence including multiple germin-like protein genes, at the wheat Sr2 adult plant stem rust resistance locus
Background
The adult plant stem rust resistance gene Sr2 was introgressed into hexaploid wheat cultivar (cv) Marquis from tetraploid emmer wheat cv Yaroslav, to generate stem rust resistant cv Hope in the 1920s. Subsequently, Sr2 has been widely deployed and has provided durable partial resistance to all known races of Puccinia graminis f. sp. tritici. This report describes the physical map of the Sr2-carrying region on the short arm of chromosome 3B of cv Hope and compares the Hope haplotype with non-Sr2 wheat cv Chinese Spring.
Results
Sr2 was located to a region of 867 kb on chromosome 3B in Hope, which corresponded to a region of 567 kb in Chinese Spring. The Hope Sr2 region carried 34 putative genes but only 17 were annotated in the comparable region of Chinese Spring. The two haplotypes differed by extensive DNA sequence polymorphisms between flanking markers as well as by a major insertion/deletion event including ten Germin-Like Protein (GLP) genes in Hope that were absent in Chinese Spring. Haplotype analysis of a limited number of wheat genotypes of interest showed that all wheat genotypes carrying Sr2 possessed the GLP cluster; while, of those lacking Sr2, some, including Marquis, possessed the cluster, while some lacked it. Thus, this region represents a common presence-absence polymorphism in wheat, with presence of the cluster not correlated with presence of Sr2. Comparison of Hope and Marquis GLP genes on 3BS found no polymorphisms in the coding regions of the ten genes but several SNPs in the shared promoter of one divergently transcribed GLP gene pair and a single SNP downstream of the transcribed region of a second GLP.
Conclusion
Physical mapping and sequence comparison showed major haplotype divergence at the Sr2 locus between Hope and Chinese Spring. Candidate genes within the Sr2 region of Hope are being evaluated for the ability to confer stem rust resistance. Based on the detailed mapping and sequencing of the locus, we predict that Sr2 does not belong to the NB-LRR gene family and is not related to previously cloned, race non-specific rust resistance genes Lr34 and Yr36
Major haplotype divergence including multiple germin-like protein genes, at the wheat Sr2 adult plant stem rust resistance locus
Background
The adult plant stem rust resistance gene Sr2 was introgressed into hexaploid wheat cultivar (cv) Marquis from tetraploid emmer wheat cv Yaroslav, to generate stem rust resistant cv Hope in the 1920s. Subsequently, Sr2 has been widely deployed and has provided durable partial resistance to all known races of Puccinia graminis f. sp. tritici. This report describes the physical map of the Sr2-carrying region on the short arm of chromosome 3B of cv Hope and compares the Hope haplotype with non-Sr2 wheat cv Chinese Spring.
Results
Sr2 was located to a region of 867 kb on chromosome 3B in Hope, which corresponded to a region of 567 kb in Chinese Spring. The Hope Sr2 region carried 34 putative genes but only 17 were annotated in the comparable region of Chinese Spring. The two haplotypes differed by extensive DNA sequence polymorphisms between flanking markers as well as by a major insertion/deletion event including ten Germin-Like Protein (GLP) genes in Hope that were absent in Chinese Spring. Haplotype analysis of a limited number of wheat genotypes of interest showed that all wheat genotypes carrying Sr2 possessed the GLP cluster; while, of those lacking Sr2, some, including Marquis, possessed the cluster, while some lacked it. Thus, this region represents a common presence-absence polymorphism in wheat, with presence of the cluster not correlated with presence of Sr2. Comparison of Hope and Marquis GLP genes on 3BS found no polymorphisms in the coding regions of the ten genes but several SNPs in the shared promoter of one divergently transcribed GLP gene pair and a single SNP downstream of the transcribed region of a second GLP.
Conclusion
Physical mapping and sequence comparison showed major haplotype divergence at the Sr2 locus between Hope and Chinese Spring. Candidate genes within the Sr2 region of Hope are being evaluated for the ability to confer stem rust resistance. Based on the detailed mapping and sequencing of the locus, we predict that Sr2 does not belong to the NB-LRR gene family and is not related to previously cloned, race non-specific rust resistance genes Lr34 and Yr36
Molecular Characterization of a Novel Methionine-Rich δ-Kafirin Seed Storage Protein Gene in Sorghum (Sorghum bicolor L.)
We have isolated, cloned, and characterized a 660 bp full length cDNA encoding a putative seed storage protein gene, delta-kafirin (AY834250), from developing seeds of sorghum (Sorghum bicolor) inbred line SPV475. Translation of the DNA sequence predicts a 16-kDa polypeptide (precursor) of 147 amino acids, rich in methionine residues (17%). Reverse Transcriptase-PCR (RT-PCR) and Real Time-PCR revealed delta-kafirin is only expressed in developing seeds. delta-Kafirin exhibited 96% identity with another methionine-rich sorghum seed storage protein (AY043223). Interestingly, this 6-kafirin gene contained two insertions rich in ATG codons encoding five more methionine residues than AY043223. Comparison of the sorghum delta-kafirin proteins with other seed storage proteins from maize, rice, and Brazil nut revealed conserved domains, mainly at the N-terminus. This similarity, in particular to the zeins, suggests these proteins shared a common ancestor and that the variation observed occurred after the separation of the species
Bean [alpha]-Amylase Inhibitor Confers Resistance to the Pea Weevil (Bruchus pisorum) in Transgenic Peas (Pisum sativum L.)
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