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1.
Gene action controlling yield and yield‐related traits among tef (Eragrostis tef [Zucc.] Trotter) populations under drought‐stressed and nonstressed conditions 
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下载免费PDF全文 This study was aimed to determine gene action for grain yield and yield‐related traits of newly developed tef populations under drought‐stressed and nonstressed conditions to improve drought tolerance. Ten crosses, along with the parents, were evaluated in the F2 generation under drought‐stressed conditions at Hastebo and Adigdad sites in 2015 and Dura site in 2016 and under nonstressed conditions at Dura site in 2016. Additive gene action predominantly controlled the inheritance of the grain yield and majority of the yield‐related traits under drought‐stressed and nonstressed conditions. Under both test conditions, the genotypes DZ‐Cr‐387 and 9415 were the best general combiners for increased grain yield and morphological traits. Conversely, genotype 222076 was the best general combiner for reduced maturity period only. The selected parents are novel genetic materials for tef breeding programmes to improve grain yield and morphological traits with reduced days to maturity for drought tolerance breeding. The family of the cross DZ‐Cr‐387 × 222076 was selected for high grain yield and early maturity in both the drought‐stressed and nonstressed environments. 相似文献
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Emiru Birhane Mengsteab Hailemariam Girmay Gebresamuel Tesfay Araya Kiros Meles Hadgu Lindsey Norgrove 《林业研究》2020,31(1):313-323
Poor land use management and practice inhibit the growth and establishment of tree seedlings in dryland areas.We assessed arbuscular mycorrhizal fungi(AM)status of Faidherbia albida(Del.)A.Chev.trees grown on different land uses.We quantified the growth and nutrient uptake of F.albida seedlings inoculated with AM from different sources.These efforts were based on soil and fine root samples from the rhizosphere soils of F.albida trees.AM root colonization was determined using the gridline intersect method.Spores were extracted by the wet sieving and decanting method and identified to genus level.The seedling experiment had a completely randomized onefactorial design with four treatments and five replications.Faidherbida albida seedlings were grown in a greenhouse.All in situ F.albida trees were colonized by AM fungi.AM root colonization of F.albida trees was significantly higher(P<0.0086)in area exclosures than on lands used for grazing or cultivation.Spore abundance was significantly higher(P<0.0014)in area exclosures followed by cultivated land and grazing land.Glomus was the dominant genus in all land-uses.AM-inoculated F.albida seedlings grew better(P<0.05)than non-inoculated controls.Seedlings inoculated with AM from area exclosure had significantly(P<0.05)higher growth and nutrient uptake than those inoculated with AM from grazing and cultivated land.This emphasizes the importance of the native soil AM potential for better establishment of seedlings to achieve optimum plant growth improvement and assist in rehabilitation of degraded arid lands. 相似文献
3.
Zelealem Tesfay Gebretsadik Anil Kumar Anal 《Tropical animal health and production》2014,46(2):341-347
A study was conducted in Tigrai, Northern Ethiopia to describe the sheep breeds and their production system. The survey was done in selected districts known for their high sheep population density. The phenotype characterization identified distinct features for each breed. The breeds are Aberegelle, Ille, Begait, and the common Tigrai highland sheep. The strong discriminating phenotypes are face profile, tail type, and compactness; accounting for 83.48, 17.95, and 2.93 % respectively of the total variability among breeds. The flock structure are affected by the market demand; requirements of breeding females and feed availability. Farmers tend to keep more female sheep for longer (culling age of 5.9?±?0.4 and 1.9?±?0.5 for females and males, respectively) for the reasons of feed shortage and need to maximize number of breeding female. The ratio of male to overall female is large (1:6) and thus a single ram gets maximum contact time with ewes and ewe lambs. The overall average age at puberty for females is 9–14 months. However, the presence of very young lamb rams and uncontrolled mating system lead to early breeding of females which results in low conception rate, low birth weight, poor survival rates, and in extreme cases causing inbreeding. It was also possible to identify the critical control points such as breed, age of animals, nutrition, and feeding systems affecting the provision of live animals for good meat quality. 相似文献
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In the discussion on targeting of development interventions there is an ongoing debate on the usefulness of geographic targeting versus targeting of specific household types. In this paper, we examine the degree to which there is heterogeneity in the diversity of livelihood strategies in comparable geographic areas in northern Ethiopia. We use the concept of development domains to quantify differences amongst specific geographic areas (communities) and estimate the degree to which development domain dimensions account for differences in production systems indicators and to what extent variability between the overall results and the observed patterns can be attributed to these development domain dimensions. Our research shows that development domain dimensions matter both for production indicators (choice of technology, investment, cropping pattern and livestock use), as well as for the occurrence of heterogeneity in those indicators. Diversity is especially linked to better market access, homogeneity in agricultural production indicators to poor soils. This offers scope for targeting development interventions. 相似文献
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Gebremeskel Destaalem Birhane Emiru Rannestad Meley Mekonen Gebre Semae Tesfay Girmay 《Agroforestry Systems》2021,95(7):1275-1293
Agroforestry Systems - Agroforestry plays a significant role in climate change mitigation through improved sequestration and storage of carbon in farmlands. However, quantitative information on... 相似文献
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G. Corral‐Nuñez D. Opazo‐Salazar G. GebreSamuel P. Tittonell A. Gebretsadik Y. Gebremeskel G. Tesfay C. L. van Beek 《Soil Use and Management》2014,30(4):487-495
Soil degradation resulting from permanent and high pressure on natural resources is a threat for the present and future of agricultural production in Ethiopia. Mono‐cropping, cultivation on steep slopes, use of cattle manure and crop residues as an energy source for cooking are common practices that have led to declining soil organic matter (SOM) contents. The objective of this research was to evaluate the current status of SOM in farmlands and exclosures (areas protected from grazing to allow their natural restoration) in Northern Ethiopia and to explore the long‐term effects of current agricultural practices and an improved scenario on SOM. At present, the SOM content of farmland soils is small, ranging from 2.1% to 2.9%, while exclosures showed a significant recovery after 20 yr of protection, with SOM contents ranging from 2.6% to 5.6%. However, the level of SOM in farmland soils is envisaged to decline given current agricultural practices, that is removal of crop residues and use of manure as an energy source for cooking. We found that applying manure alone appeared to be insufficient to revert this trend, due to limited availability and its alternative uses. Therefore, a multidisciplinary approach including improved manure and compost management needs to be supplemented with energy saving techniques, as fuel use is currently the largest competing claim for organic matter in the area. 相似文献
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Mulubrhan Balehegn Lars Olav Eik Yayneshet Tesfay 《Tropical animal health and production》2014,46(5):889-894
Ficus thonningii (FT) is an important multipurpose fodder tree providing economic and ecological benefits across arid and semi-arid areas in Africa. Despite its availability in many Sub-Saharan African countries, there is lack of information on its effect on animal productivity. Twenty-four male weaned highland goats of age 7?±?1.5 months were randomly assigned to four dietary treatments in a completely randomized block design. All animals were fed wheat straw, water, and salt licks ad libitum. The control group (T1) was fed concentrate mixture at 2 % of their body weight, while in T2, T3, and T4, 25, 50, and 75 % of the weight of concentrate (DM basis), respectively, was replaced by sun dried FT leaf meal. FT leaf meal had acceptable levels crude protein (CP), neutral detergent fiber (NDF), and tannins and has resulted in increased body weight in all treatments. Goats fed T3 diet showed significantly higher (P?<?0.05) values in terms of feed intake, body weight gain, some carcass attributes, and local meat quality indicators than the rest of the treatments. An increase in proportion of FT leaf meal beyond 50 %, however, resulted in decreased body weight gain, and other carcass parameters, despite increased feed intake. Therefore, F. thonningii can be used to replace commercial concentrate mixture up to 50 % to improve feed intake and productivity of Ethiopian highland goats. 相似文献
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In most parts of tropical Africa, conversion of forests into agricultural lands is often accompanied by drastic changes in soil properties. However, little study has been done to examine changes in biological properties of soils from different land-uses in response to addition of C and nutrients. We conducted this study with the aim of investigating nutrient limitations for microbial activity in soils from agricultural (farm) and forest land-uses at Wondo Genet (Ethiopia) after amendment with C and limiting nutrients. We measured CO2 respiration rates from the soils incubated in the laboratory before and after addition of glucose-C together with N and/or P in excess and/or limiting amounts. Based on the respiration kinetics, we determined the basal respiration (BR), substrate-induced respiration (SIR), specific-microbial growth rate (μ), respiration maxima (Rmax), % of glucose-C respired, and microbially available N and P in the soils. We found that N was more limiting than P for the micro-biota in the soils considered, suggesting the presence of ample amounts of indigenous P that could be extracted by the micro-biota, if provided with C. Addition of P resulted in a respiration pattern with two peaks, presumably reflecting different N pools being available over time. The SIR, Respiration maxima, μ and microbially available P were higher in soils from the farm, while %C respired was higher in the forest, suggesting increased C costs for micro-biota to be able to utilize nutrients that are strongly bound to organic-matter or clay minerals. Depending on land-use, about 49-69% of added glucose-C was respired during two and a half weeks time, but differences between N or P additions were not significant. The correlation between soil physical and chemical properties and respiration parameters, however, depended on whether N or P was limiting. We concluded that examining the soil respiration kinetics could provide vital information on nutritional status of micro-organisms under different land-uses and on potential availability of nutrients to plants. 相似文献
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This study investigated the effect of replacing noug (Guizotia abyssinica) (L.f.) Cass. seed cake by dried Leucaena leucocephala (Lam.) de Wit leaves on feed intake, live weight gain, nutrient digestibility, and nitrogen balance of highland sheep in Tigray Region in northern Ethiopia. Twenty intact yearling male highland sheep weighing16.9?±?1.62 kg were used in a randomized complete block design and included the following four treatments: T1 (control, wheat straw ad libitum?+?200 g noug seed cake (NSC)?+?150 g wheat bran (WB)); T2 (wheat straw ad libitum?+?170 g NSC?+?44.3 g dried L. leucocephala (DLL)?+?150 g WB); T3 (wheat straw ad libitum?+?140 g NSC?+?87.3 g DLL?+?150 g WB); and T4 (wheat straw ad libitum?+?110 g NSC?+?130.2 g DLL?+?150 g WB). Sheep fed on T4 diet consumed higher total dry matter (658 g/head/day) and recorded the highest average daily weight gain (59 g/head/day). Sheep fed on T4 diet had higher dry matter (61 %), organic matter (63 %), and crude protein (75 %) digestibility values than the other treatments. Sheep fed on T3 diet demonstrated higher feed conversion ratio (11.93) than sheep kept on the other treatments. All sheep exhibited positive nitrogen balance, with the highest nitrogen retention being measured in T4 (12 g/head/day). It is concluded that partially replacing NSC by DLL can improve total dry matter intake, digestibility of nutrients, and body weight gain in highland sheep fed on wheat straw as the basal diet. 相似文献
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