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21.
On-farm conservation of plant genetic resources for food and agriculture has received strong support worldwide in recent years.
It has been justified on appealing assumptions: it complements ex situ conservation, allows co-evolutionary interaction of host–pathogens and crop–weed complexes, and involves local knowledge
systems. This article illustrates how on-farm conservation being set for its sake is extremely difficult under farmers’ dynamic
management of plant genetic resources based on sorghum. The dynamics of their management could be explained by continued introduction,
displacement, loss and maintenance of aboriginal landraces that have distinct functional attributes, patch-occupancy and relative
abundance profiles. Such management and hence the dynamic landrace demography has largely been triggered by co-evolving biophysical
stresses, spatial and seasonal variations. The best viable alternative to support farmers’ management of genetic resources
is to link conservation to crop improvement both to enhance on-farm genetic diversity and make the biophysical environment
a comfortable home for the plant genotypes. 相似文献
22.
Yayeh Bitew Getachew Alemayehu Enyew Adego Alemayehu Assefa 《Journal of plant nutrition》2020,43(12):1824-1839
AbstractTraditional short-term diversification of annual crops for the purpose of improving soil fertility and food security is a common practice in Ethiopia. However, the best cropping systems have not been selected yet though field research. Experiments were conducted for two years with an objective of establishing sustained finger millet based short term cropping sequence in two major finger millet producing areas of Ethiopia. The experiments were laid out in a split-plot arrangement with six precursor crops (haricot bean, maize, sweet lupine, niger seed, wheat, and teff) as a main plot factor, where determined residues were retained in the main plot after harvesting and two nitrogen fertilizer levels (30 and 60?kg ha?1) applied for finger millet as sub-plots with three replications. Soil analysis result examined immediately after finger millet harvest showed a significant effect of precursor crops and nitrogen fertilizer rates on soil properties. Planting finger millet following lupine increased the soil organic carbon, total nitrogen and cation exchange capacity by 17.37%, 65.50%, 26.15%, respectively, over planting finger millet following teff. Use of different amount of nitrogen fertilizer likely contributed to observed differences in residual soil nutrients. Accordingly, finger millet following lupine with the addition of 60?kg ha?1 nitrogen fertilizer gave significantly higher finger millet grain yield (3.24 tone ha?1) and relative production (22.37%) and economic (40.7%) efficiency. This system with their high sustainability and multiple benefits can be readily accepted by the farming community. 相似文献
23.
24.
Bitew M Andargie A Bekele M Jenberie S Ayelet G Gelaye E 《Tropical animal health and production》2011,43(8):1543-1547
A cross-sectional serological survey was undertaken in selected districts of different agro-ecology of Jimma zone (Dedo, Yebu,
Seka, Serbo, and Jimma town) from November 2009 to February 2010 to determine the seroprevalence of African horse sickness
virus and associated risk factors of the disease. Two hundred seventy-four equids (189 horses, 43 mules, and 47 donkeys) with
a history of non-vaccination for at least 2 years were selected randomly from the above areas. Sera samples were collected
and assayed for the presence of specific antibody against African horse sickness virus using blocking ELISA. An overall seroprevalence
of 89 (32.5%) was found and it was 24 (51.1%) for donkeys, 13 (30.2%) for mules, and 52(28.3%) for horses. Seroprevalence
was significantly (X
2 = 11.05, P < 0.05) different among the different species of equids. Seroprevalence was also significantly (X
2 = 11.43, P < 0.05) different among the different agro-ecological areas being higher in highlands 47 (40.5%) followed by midland 30 (34.5%)
and lowland 12 (16.9%). Age and sex were not significantly (X
2 = 3.15, P > 0.05 and X
2 = 3.38, P > 0.05, respectively) associated with seroprevalence of AHSV. The present study showed that African horse sickness (AHS)
is highly prevalent disease for the horses followed by mules and then donkeys in Jimma zone explained by lower seroconversion
rate. Therefore, control strategy against AHS should target at high risk species of all age and sex in their locality in the
initial stage for better containment of the disease. 相似文献
25.
Khuliso E Ravhuhali Victor Mlambo Tefera S Beyene Lobina G Palamuleni 《African Journal of Range and Forage Science》2019,36(1):67-70
The comparative growth habits and nutritive value of native grass species of South Africa are largely unknown despite the utility of this information in rangeland restoration efforts. This article presents a comparative characterisation of the morphology, chemical composition and in vitro ruminal fermentation of Urochloa mosambicensis, Cymbopogon pospischilii, Eragrostis superba, Fingerhuthia africana and Eragrostis bicolor when grown under controlled conditions. Species were analysed for height, number of leaves, number of tillers, stem diameter and leaf width at different growth stages, whereas chemical composition and in vitro ruminal dry matter degradability (DMD) were assessed at maturity stage. Grass species and growth stages significantly influenced morphological characteristics. Eragrostis superba and U. mosambicensis had the highest number of leaves at the reproductive stage. Urochloa mosambicensis ranked highest in terms of rangeland restoration potential when all morphological parameters were considered, followed by E. superba and C. pospischilii. With the highest crude protein, low acid-detergent lignin and higher DMD at 48 h, F. africana and C. pospischilii have the highest potential feed value. Across the three most suitable native grass species, U. mosambicensis, E. superba and C. pospischilii, there is sufficient genetic diversity that suggests that these plants may play different and complementary ecological roles in the communal rangeland ecosystem. 相似文献
26.
T. J. Beyene M. C. M. Mourits C. W. Revie H. Hogeveen 《Zoonoses and public health》2018,65(4):443-453
The objective of this study was to identify factors that determine medical treatment seeking behaviour following potential rabies exposure after being bitten by a suspected dog and the likelihood of compliance to receive sufficient doses of post‐exposure prophylaxis after the visit to a health centre visit. A detailed survey based on case investigation was conducted on suspected rabid dog bite cases in three areas of Ethiopia. Two multivariable logistic regression models were created with a set of putative variables to explain treatment seeking and compliance outcomes. Based on the registered bite cases at each health centre and the set of unregistered bite cases derived by contact tracing, 655 bite victim cases were identified to have occurred between September 2013 and August 2014. Of these evaluated bite incidences, 465 cases were considered to have been caused by a potentially rabid dog. About 77% of these suspected rabid dog bite victims visited a health centre, while 57% received sufficient doses of PEP. The overall likelihood of seeking medical services following rabies exposure was higher for people bitten by dogs of unknown ownership, where the bite was severe, being bitten on the leg, spend of more than 100 USD per month and where the victim lived close to the nearest health centre, while the likelihood of receiving sufficient doses of PEP was sensitive to monthly spending and distance to health centre. However, the evaluated factors did only explain a part of the variation among the three districts. The district in which victims lived appeared to have a relevant influence on the likelihood of seeking medical treatment but did not improve the prediction on the likelihood of treatment compliance. Given the insights obtained from this study, improvements in the rural districts with regard to accessibility of post‐exposure prophylaxis delivering health centres in shorter distance could improve health seeking behaviour. In addition, in rural districts, majority of exposed persons who seek medical treatment tend to comply with treatment regimen, indicating that the promotion of medical treatment through awareness creation campaigns could be beneficial. 相似文献
27.
Bitew Beyene Fininsa Chemeda Terefe Habtamu Ahmed Seid 《Journal of Crop Science and Biotechnology》2023,26(2):135-149
Journal of Crop Science and Biotechnology - Faba bean is a cool season food legume crop. However, productivity of the crop is constrained by faba bean gall (FBG), which is an emerging disease that... 相似文献
28.
Isaac Kamweru Yoseph Beyene Bruce Anani Victor O. Adetimirin Boddupalli M. Prasanna Manje Gowda 《Plant Breeding》2023,142(5):607-620
Fall armyworm (FAW, Spodoptera frugiperda) emerged as a major lepidopteran pest destroying maize in sub-Saharan Africa. A diallel mating design was used to generate 210 experimental hybrids from 21 lines. Experimental hybrids and four checks were evaluated in two locations. Commercial checks suffered higher foliar and ear damage compared to the top 15 hybrids. Mean squares associated with the genotypic variation were higher than genotype-by-environment interactions for foliar and ear damage traits. Heritabilities were moderate to high. Significant correlations were observed between grain yield (GY) with ear rot (−0.54) and ear damage (−0.45). Positive and significant GCA effects were observed for GY in seven parental lines, which were developed from multiple insect resistance breeding programmes. CKSBL10153 has the highest GCA value for GY and shows significant GCA effects for foliar and ear damage traits. These lines were identified as the ideal combiners for GY and FAW resistance and are therefore recommended for utilization as testers in the development of FAW-resistant three-way cross-hybrid maize with correlated response for increased GY. GCA and marker-based prediction correlations of GY were 0.79 and 0.96, respectively. Both GCA effects and marker-based models were effective in predicting hybrid performance for FAW resistance. 相似文献
29.
B. Megersa B. Beyene F. Abunna A. Regassa K. Amenu T. Rufael 《Tropical animal health and production》2009,41(6):891-898
A serological survey to investigate risk factors for Foot and Mouth Disease (FMD) occurrence was conducted between October
2007 and March 2008 in Southern Ethiopia. Antibodies against non-structural protein of FMD virus (using 3abc ELISA) were measured
as indicator of exposure to the virus. The seroprevalence of FMD was 9.5% (95%CI = 7.7 – 11.3, n = 1020) and 48.1% (95% CI = 36.8
– 59.4%, n = 79), respectively at animal and herd levels. Within herd seropositivity was ranged from 6.7 to 46.7% with 18.6%
(95%CI = 14.6 – 22.5%) risk of being seropositive for an animal in positive herds. The most important herd level risk factors
identified were pastoral system (OR = 16.3, 95% CI = 2.0 -133.7) compared to sedentary, low altitude (OR = 7.5, 95% CI 1.4
-40.7) compared to high altitude, keeping cattle with small ruminants (OR = 5.1, 95% CI 1.0 -25.2) when compared to one species
or alone. Seroprevalence was significantly higher (P <0.05) in South Omo than Sidama and Gamo Gofa areas. The odds of seropositivity
were 2.8 and 2.3 times higher in the adult (>4 years) and maturing animals (3–4 years) compared to young age category (<3 years).
Both multivariable logistic and negative binomial regressions depicted that production system was the major risk factor for
FMD seropositivity. Consequently, higher prevalence of FMD in pastoral system where animals are an integral part of life has
substantial livelihood and economic implications, which signifies the need for devising control measures. 相似文献
30.
Yoseph Beyene Stephen Mugo Kassa Semagn Godfrey Asea Walter Trevisan Amsal Tarekegne Tadele Tefera James Gethi Barnabas Kiula John Gakunga Haron Karaya Andrew Chavangi 《Euphytica》2013,192(3):379-392
In contrast to conventional inbreeding that takes up to seven generations to develop inbred lines, the doubled haploid (DH) technology allows production of inbred lines in two generations. The objectives of the present study were to: (a) evaluate testcross performance of 45 doubled haploid lines under drought stress and non-stress conditions (b) estimate heritabilities for grain yield and other traits and (c) to assess the genetic distance and relationship among the DH lines using 163,080 SNPs generated using genotyping-by-sequencing (GBS). The 45 hybrid and five checks were evaluated using a 10 × 5 alpha lattice in six drought stress and nine well-watered environments in Kenya, Uganda, and Tanzania. Differences in trait means between the drought stress and well-watered conditions were significant for all measured traits except for anthesis date. Genetic variances for grain yield, grain moisture, plant height and ear height were high under well-watered environments while genetic variance for anthesis date, root lodging and stalk lodging were high under drought stress environments. Combined analyses across drought stress and well-watered environments showed that ten top hybrids produced 1.6–2.2 t/ha grain yield under well-watered condition and 1–1.4 t/ha under drought stress condition higher than the mean of the commercial checks. Genetic distance between pairwise comparisons of the 38 of the 45 DH lines ranged from 0.07 to 0.48, and the overall average distance was 0.36. Both cluster and principal coordinate analysis using the genetic distance matrix calculated from 163,080 SNPs showed two major groups and the patterns of group was in agreement with their pedigree. Thirteen (13) of the best hybrids are currently in National Performance Trials testing, an important step towards commercialization in Kenya, Tanzania and Uganda. 相似文献