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Wakjira K.,Addis Ababa Institute of Technology | Wakjira K.,Oromia Agricultural Research Institute | Negash L.,Addis Ababa Institute of Technology
South African Journal of Botany | Year: 2013

Croton macrostachyus Hochst. ex Del. (Euphorbiaceae) is a multipurpose, deciduous, and medium sized tree of pantropic occurrence. Because the species has numerous useful qualities (e.g., establishment and growth in disturbed sites, drought tolerance, fast growth rate, copious litter/necromass production, suitability for agroforestry, and ability to attract avian frugivores), its speedy restoration has become increasingly critical. Germination studies were therefore conducted on seeds pooled from five widely located provenances with a view to supporting efforts geared toward the speedy propagation and restoration of this valuable tree species. Seed pretreatments were achieved using various dilution levels of plant-derived smoke-water (1:1, 1:10, 1:100 and 1:1000), as well as gibberellic acid (GA3) or potassium nitrate (KNO3) ranging in concentration from 0.1 to 100μmol. The control was to use distilled water for seed pretreatment. Seeds were germinated under either illuminated (ca 60μmolm-2s-1; cool-white fluorescent lamp) or non-illuminated conditions. Experiments on the impact of seed storage durations, as well as storage temperatures were also conducted. The study found that germination percentage (GP: ca 90%), and mean germination time (MGT: 14days) were significantly (P<0.001) better when seeds were pretreated with smoke-water and germinated under non-illuminated conditions, than when these were pretreated with various concentrations of GA3 or KNO3 (GP and MGT of ca 65% and 20days, respectively). Germination percentage (GP) and germination vigor (GV) declined with increasing storage-time for all storage temperatures, but GV's decline was faster for seeds stored at 22°C than for those stored at 5 and 15°C. On the other hand, mean germination time (MGT) increased significantly (P<0.01) with seed storage-time of up to 8months at 5, 15, and 22°C, but the increase was more marked for seeds stored at 22°C than for those stored at 5 and 15°C. From these investigations, it is concluded that germination of C. macrostachyus seeds through use of smoke-water is faster, cheaper, and technically less demanding, compared to that of either GA3 or KNO3. The study also concludes that C. macrostachyus is intermediate between orthodox and recalcitrant seeds, and that it is non-photoblastic. © 2013 South African Association of Botanists. Source

Wondimu T.,Oromia Agricultural Research Institute | Alamerew S.,Jimma University | Garedew W.,Jimma University
International Journal of Agricultural Research | Year: 2014

Forty nine anchote landrace populations collected from South and Western parts of Ethiopia were evaluated for 17 pheno-morphic and agronomic traits of yield and yield related traits in simple lattice design at Bako Agricultural Research Center during 2011 cropping season. The objectives of the study were to classify the population into relatively homogenous group and to identify the major traits contributing to the overall diversity of the population. The data were subjected to D2 analysis and the populations were clustered in to 5 different major groups according to their similarity levels and this makes the accessions to become moderately divergent. This dataset was reduced to three significant Principal Components (PCs) that cumulatively explained 93.50% of the variance. About 56.30% of the variance accounted for by the first PC alone resulted largely from the variations in contrasting effects of discriminatory traits like fruit yield per plant, fruit length, fruit weight, fruit diameter, hundred seed weight, petiole length, number of fruit per plant, leaf length, average root length, internodes length, vine length and root yield per plant. Overall, the study confirmed the presence of character diversity in anchote landraces. This assessment of traits diversity can assist geneticist and breeders to identify populations with desirable characteristics for inclusion in variety breeding program. Further evaluation at multi-location is suggested in the future. © 2014 Academic Journals Inc. Source

Abinasa M.,Sinana Agricultural Research Center | Ayana A.,Oromia Agricultural Research Institute | Bultosa G.,Haramaya University
African Journal of Agricultural Research | Year: 2011

Information on the extent of genetic variability and heritability as well as correlation among agronomically important traits is a requirement to design a suitable plant breeding method. The present research was conducted at Sinana, Southeastern Ethiopia during the 2009 main crop growing season. The experimental material consisted of 16 durum wheat genotypes tested in a randomized complete block design with three replications. Twelve agronomic traits were included in the investigation. Highly significant differences were revealed among durum wheat genotypes for all traits studied, suggesting the possibility of improving durum wheat for these traits. Plant height and number of kernels per spike showed the highest phenotypic and genotypic coefficients of variations and genetic advance, whereas, days to maturity and test weight had the lowest values. Plant height exhibited highest heritability value of 98.3% while number of spikelets per spike showed minimum value of 36.4%. The genotypic correlations estimated showed positive association of grain yield with days for heading (r=0.50), harvest index (r=0.69) and kernels number per spike (r=0.81). Harvest index (1.13) and biomass (0.81) exhibited the highest positive and significant direct effect on grain yield. Hence, these traits could be considered as suitable selection criteria for the development of high yielding durum wheat varieties. © 2011 Academic Journals. Source

Birhan T.,Jimma University | Zeleke H.,Haramaya University | Ayana A.,Oromia Agricultural Research Institute
Indian Journal of Agricultural Research | Year: 2013

Hundred pigeon pea genotypes were tested in a 10 × 10 simple lattice design at Areka Agricultural Research Center during 2009 rain feed cropping season. Correlation coefficients and path coefficients (partitioned into direct and indirect effects) were estimated on yield and its contributing traits. Seed yield had positive and significant phenotypic and genotypic association with plant height, biomass yield per plant, pods per plant, seeds per plant, days to maturity, days to flowering, seeds per pod, reproductive phase and seed yield per plant. Phenotypic path analysis showed that, days to maturity had the highest positive direct effect on seed yield followed by plant height and seeds per plant whereas; genotypic path analysis revealed that, maximum direct effect on seed yield was exerted by days to flowering and reproductive phase followed by seeds per plant and plant height. Thus, seeds per plant and plant height were the potent contributor to seed yield which could be used as indirect selection criteria. The results from correlation and path coefficient analyses showed that selection for yield improvement through days to flowering, plant height, seeds per plant, pod filling duration and biomass yield per plant appeared promising. Source

Duguma G.,International Livestock Research Institute ILRI | Duguma G.,University of Natural Resources and Life Sciences, Vienna | Duguma G.,Oromia Agricultural Research Institute | Mirkena T.,International Livestock Research Institute ILRI | And 9 more authors.
Animal | Year: 2011

Identification of breeding objective traits pertinent to specific production environments with the involvement of target beneficiaries is crucial to the success of a breed improvement program. A choice experiment was conducted in four locations representing different production systems and agro-ecologies that are habitat to four indigenous sheep breeds (Afar, Bonga, Horro and Menz) of Ethiopia with the objective of identifying farmers'/pastoralists' preferences for sheep breeding traits. Following a synthesis of secondary information and diagnostic surveys, two communities per location consisting of 60 households each having at least four breeding ewes were identified. Producers' priority attributes used in the choice sets were identified through in-depth production system studies conducted from December 2007 to March 2008. On the basis of prior information, four to seven attributes were used to design choice sets with different profiles in order to capture results that mimic real life of the different communities. The attributes and levels chosen for the sheep profile were as follows: body size (large/small), coat color (brown/white/black), tail type (good/bad) for both rams and ewes; horn (polled/horned) and libido (active/poor) for rams; and lambing interval (three lambings in 2 years/two lambings in 2 years time), mothering ability (good mother/bad mother), twinning rate (twin bearer/single bearer) and milk yield (two cups per milking/one cup per milking) for ewes. A fractional factorial design was implemented to construct the alternatives included in the choice sets. The design resulted in a randomized selection of 48 sheep profiles (24 sets) for both sexes, which were grouped into four blocks with six choice sets each. An individual respondent was presented with one of the four blocks to make his/her choices. Results indicate that producers' trait preferences were heterogeneous except for body size in rams and mothering ability in ewes where nearly homogeneous preferences were investigated. In the pastoral production system, attention was given to coat color of both breeding rams and ewes, favoring brown and white colors over black. Ram libido influenced producers' decisions in Bonga, Horro and Menz areas. The influence of milk yield and twinning on respondents' decision making was high in Afar and Horro, respectively. Breeders in all areas attempt to combine production and reproduction traits as well as they can in order to maximize benefits from their sheep. The elicited measurable objective traits were used to design alternative community-based sheep breeding plans for the four indigenous sheep breeds in their production environments that have been implemented since. © 2011 The Animal Consortium. Source

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