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Getaneh K. Ayele Azalu A. Gessess Meseret B. Addisie Seifu A. Tilahun Tigist Y. Tebebu Daregot B. Tenessa Eddy J. Langendoen Charles F. Nicholson Tammo S. Steenhuis 《Land Degradation \u0026amp; Development》2016,27(2):270-280
Gully erosion reduces agricultural productivity by destroying valuable land resources, increases sediment concentrations, reduces water quality, and fills up reservoirs. Gully rehabilitation has proven to be challenging especially in the high‐rainfall areas of the Ethiopian Highlands and has therefore had limited success. This paper describes a successful low‐cost gully rehabilitation effort with community participation in the Birr watershed in the Blue Nile basin that begun in early 2013. Initially, farmers were reluctant to participate for religious reasons, but with the aid of local priests and respected elders, community discussions, and a visit to a rehabilitated gully, a consensus was reached to rehabilitate a 0·71‐ha upland gully. The rehabilitation measures consisted of regrading the gully head at a 45° slope, constructing low‐cost check dams from locally available materials, and planting Pennisetum purpureum grass and Sesbania sesban. At the end of the first post‐implementation rainy season, 2,200 tons of soil was conserved by the constructed check dams and newly planted vegetation, compared with soil losses of 680 and 560 tons in two untreated, nearby gullies. In 2014, an additional 3,100 tons of soil was conserved. In 2013, the marginal rate of return (MRR) on the gully rehabilitation investment was 2·6 based on the value of increased forage production alone. When we include trapped soil nutrient values, the rehabilitation MRR was increased to 10. Although these numbers are impressive, the best proof of the success was that farmers on their own initiative rehabilitated an additional five gullies in 2014. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Tewodros Eshete Solomon Gizaw Eyassu Seifu 《Tropical animal health and production》2012,45(1):177-184
The experiment was conducted to determine feed intake, digestibility, body weight change, carcass characteristics, and sensory quality of meat of Menz sheep supplemented with a concentrate mix and combinations of different proportions of tossign (Thymus serrulatus). Twenty yearling intact male Menz sheep were divided according to their initial body weight into five blocks of four animals in a randomized block design, and treatments were assigned randomly to each sheep within each block. The treatments were a basal diet of hay alone (T1) and supplemented with 300 g concentrate mix (T2), 200 g concentrate mix?+?100 g tossign (T3), and 100 g concentrate mix?+?200 g tossign (T4) on a dry matter basis. The results indicated that supplementation of tossign together with concentrate mix significantly increased (P?<?0.001) feed intake and improved DM and nutrient digestibility compared to the non-supplemented group. Supplementation of tossign with concentrate significantly improved (P?<?0.001) daily weight gain, feed conversion efficiency, and carcass characteristics of sheep compared to the non-supplemented group. Flavor and aroma scores of meat samples of sheep in T3 and T4 were significantly higher (P?<?0.001) than the corresponding values in T1 and T2. The scores for tenderness, juiciness, and degree of marbling of meat samples of sheep were significantly higher (P?<?0.001) in T3 and T4 compared to meat samples of sheep in T1. Inclusion of small amounts of tossign as additive in concentrate mix supplementation can improve the sensory quality of meat of Menz sheep. 相似文献
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Summary Esterase isozymes of tetraploid wheat landraces originating from four localities in the central highlands of Ethiopia were studied using the horizontal starch gel electrophoresis. The landraces studied consisted of 60 Triticum turgidum L., one T. dicoccon Schrank, one T. polonicum L. and an improved local cultivar. One introduced durum cultivar was also included for comparison.A total of 12 esterase zymograms were detected in the landraces. Among these, the types C, A and G were found to be the most prevalent. The esterase isozymes exhibited high variation in the landraces. The esterase zymograms of the introduced durum cultivar and T. dicoccon differed from those of the landraces while the patterns attained in T. polonicum and the improved local cultivar were identical to those of the other landraces.The total number of bands detected was 10, of which 2 were rare, being displayed by only 1 pattern each. The band content of zymograms was in the range of 3–6 and the average was 4. The unique bands were observed in zymograms with both high and low prevalences in the landraces. Two zymograms, including zymogram C which had the highest frequency, occurred in all the localities. The high yielding landraces displayed 4 of the zymograms, one of which belonged to two of the zymograms with widest distribution. 相似文献
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Evaluating spawning performance among captive Florida pompano Trachinotus carolinus broodstock using microsatellite‐based parentage assignment 
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下载免费PDF全文 Qian Ma Seifu Seyoum Michael D. Tringali Matthew J. Resley Nicole R. Rhody Kevan L. Main Kenneth M. Leber 《Aquaculture Research》2017,48(11):5506-5516
Florida pompano has been identified as a promising candidate for commercial‐scale aquaculture production, but to date, little information is available regarding captive broodstock spawning characteristics. Genetic markers were tested for their power in monitoring mating outcomes and potential in analysing heritability of rapid growth trait in Trachinotus carolinus. A total of 20 unrelated adults (10 females and 10 males) were chosen for a hormone‐induced mass spawning event. The 515 fastest growing and 485 slowest growing fish of the total 4852 offspring were considered a selected progeny stock, and fish were collected at 45 days post hatch based on their growth traits. Parentage analyses based on the 20 breeders and 1,000 selected progeny were performed using a total of nine microsatellite markers, a 100% assignment rate was achieved, and a four‐marker set was the minimum number for the parentage assignment. The effective breeding number for the selected progeny was 11 (six females and five males), among which three females and two males were predominant contributors with the total contribution of 95.8% and 94.7% respectively. The proportion of fast‐growing offspring from broodfish and each mating cross (sire/dam) was used for detecting whether variation in growth of the offspring was related to parental stocks. Results showed that three adults and their mated combination exhibited the greatest fast‐growing offspring proportion (69.73% and 55.95%). This research provided new information regarding spawning performance and parental contribution during mass spawning events; both important first steps towards developing improved management strategies for captive Florida pompano broodstock. 相似文献
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Tesfaye Tesemma Seifu Tsegaye Getachew Belay Efrem Bechere Demissie Mitiku 《Euphytica》1998,102(3):301-308
Plant breeding has always been concerned with genotype-environment interaction. Normally high and stable performance are desirable
attributes of cultivars. However, this is practically difficult to achieve where environmental variations are high and unpredictable
and significant genotype-environment interactions occur. Stability of performance of 13 landraces evaluated at 4 different
locations for 3 years in the highlands of Ethiopia was investigated. The testing locations have different climatic and edaphic
conditions providing the conditions necessary for the assessment of stability. Stability parameters like b, s2d, s2, r2 and cv which are in common use were employed. Grain yield and 1000-kernel weight were the agronomic traits considered for
the stability analysis. There were differences in the ranks of genotypes across the locations. Significant main environmental
as well as interaction effects were observed showing the importance of genotype-environment interaction in both traits. Many
of the landraces evaluated are rated as stable for these traits within the environmental conditions prevailing in these highland
locations. Genotypes with specific adaptation to poor and favourable conditions were also identified. Certain genotypes showed
similar manners of adaptation and stability for both of the traits. Grain yield showed low correlations with the stability
parameters showing the possibility of attaining high yield and stability. Correlations between the stability parameters were
mainly positive and significant for grain yield. Only a few of these correlations were found to be significant for kernel
weight. The good adaptability of landraces should be exploited in the improvement of their yield potential.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Summary Ethiopian landraces of tetraploid wheat can be grouped according to their seed colors in three major groups: brown, purple and white seeded. Seeds with different colours are used for different purposes, and the three seed colour groups are treated separately in breeding programs. The genetic variation between and within these groups was studied by isozyme analyses at six highly polymorphic loci in sixty landrace agrotypes. The mean number of alleles per locus was 1.95. The mean allele frequencies showed significant variation both within and between the seed colour groups. The brown and white seeded types had very high genetic identity and the genetic identity values between the brown and purple and the purple and white groups were only slightly smaller. The average coefficient of gene differentiation between the seed colour types was very low. Only about 5% of the total genetic variation was due to differences between the seed colour groups. This indicates that agrotypes of different seed colours can not be treated as genetically separate and distinct groups. 相似文献
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