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Under rainfed agriculture without supplementary supply, crop failure due to erratic rainfall has become a common phenomenon in many regions of Ethiopia. Spate irrigation development with storage provision at the 5,000 ha Boru Dodota Spate Irrigation Scheme is one of the initiatives to move away from exclusively rain-dependent agriculture. This initiative has faced several challenges. Lack of design experience and failure to fully grasp the unpredictable nature of the spate flow caused the Boru Dodota Spate Irrigation Scheme to be implemented without considering the necessity of storage ponds. In addition, absence of a systematic approach to assist planners has resulted in non-optimal design of ponds’ capacity and operation. The study, on which this article is based, aimed at optimum storage operation to irrigate the maximum possible area with the existing ponds’ capacity and available water resource. During the study, the surface storage and irrigation scheme planning model was developed and used to analyze several pond operation scenarios in Boru Dodota Spate Irrigation Scheme. The main findings were as follows: (1) Supplementing the rainfall with the operation of the existing 19 ponds that enable weekly irrigation frequency results in irrigating at least 6,600 ha. (2) An increase in the number of ponds does not always guarantee an increase in the size of irrigated land because the water resources, the operation, and management are defining factors. (3) It is not economical to only rely on spate flow for irrigation as even with 200 ponds, a maximum of 1,250 ha could be irrigated. 相似文献
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Tadesse Mehari 《Potato Research》2007,50(3-4):297-299
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Belay Miesho Mehari Hailay Ulemu Msiska Awio Bruno Geoffrey M. Malinga Patrick Obia Ongom Richard Edema Paul Gibson Patrick Rubaihayo Samuel Kyamanywa 《Plant Breeding》2019,138(5):605-613
Cowpea is an important legume crop widely grown in sub‐Saharan Africa for food and feed. However, it is largely challenged by bruchid, a serious storage pest resulting in losses in quantity and quality of grains. Therefore, this research was designed to contribute to the breeding of cowpea resistance to bruchid through the identification of candidate genes associated with resistance to bruchid. A total of 217 mini‐core cowpea accessions were genotyped and phenotyped for their reactions to bruchid. To determine the genomic regions linked with bruchid resistance, 41,948 polymorphic SNP markers were used. Genome‐wide association study identified 11 SNPs linked to the average number of eggs, holes, insect emergence and development period and Dobie susceptibility index. Gene search via Phytozome identified six candidate genes (Vigun08g132300, Vigun08g158000, Vigun06g053700, Vigun02g131000, Vigun01g234900 and Vigun01g201900) associated with the resistance traits. These candidate genes could be incorporated into the farmers preferred but susceptible cowpea varieties to bruchid. The SNP markers associated with the resistance traits can be used in marker‐assisted breeding for accurate and rapid screening of cowpea resistant genotypes to bruchid. 相似文献
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Hailay M. Gebremedhn Ulemu M. Msiska Miesho B. Weldekidan Thomas L. Odong Patrick Rubaihayo Phinehas Tukamuhabwa 《Plant Breeding》2020,139(5):943-949
Online databases containing genetic information are crucial to extract new candidate genes from existing data and web-based resources. The objective of this study was, therefore, to predict putative candidate genes associated with resistance to SBR in line UG-5 and understand their functions using different bioinformatics tools from the online available databases. The physical positions for the flanking markers of the identified putative QTLs were searched on the SoyBase database genome browser based on Glyma 1.01 assembly. The putative candidate genes and annotated functions of the surrounding genes were discovered in the vicinity using SoyBase and Phytozome databases. A total of 18 putative candidate genes were predicted on approximately 482.7 kb region of QTL-3 (chromosome 18), among which, six putative candidate genes were found to encode leucine-rich repeat (LRR), Ser/Thr protein phosphatase, leucine-rich repeat receptor-like protein kinase (LRR-RLK) and chitinase-related proteins, which are associated with plant defence signalling pathways. Moreover, F-box and leucine-rich repeat, glycosyltransferase family member and serine/threonine-protein phosphatase 2A catalytic subunit coding genes were predicted on the novel putative QTL detected on chromosome 9. This information could, therefore, be used for further prediction and annotation of candidate genes from sequenced regions of line UG-5 as these putative candidate genes were predicted from the Glyma 1.01 assembly. 相似文献
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Mehari Z. Tekeste Harold M. Hanna Erica R. Neideigh Andrew Guillemette 《Soil Use and Management》2019,35(2):293-302
A 762‐mm‐diameter pipe 1,886 km long was installed to transfer crude oil in the USA from North Dakota to Illinois. To investigate the impact of construction and restoration practices on long‐term soil productivity and crop yield, vertical soil stresses induced by a Caterpillar (CAT) pipe liner PL 87 (475 kN vehicle load) and semi‐trailer truck (8.9 kN axle load) were studied in a farm field. Soil properties (bulk density and cone penetration resistance) were measured on field zones within the right‐of‐way (ROW) classified according to construction machine trafficking and subsoil tillage (300‐mm‐depth tillage and 450‐mm‐depth tillage in two repeated passes) treatments. At 200 mm depth from the subsoiled surface, the magnitude of peak vertical soil stress from trafficking by the semi‐truck trailer and CAT pipe liner PL 87 was 133 kPa. The peak vertical soil stress at 400 mm soil depth appeared to be influenced by vehicle weight, where the Caterpillar pipe liner PL 87 created soil compaction a magnitude of 1.5 greater than from the semi‐trailer truck. Results from the soil bulk density and soil cone penetration resistance measurements also showed the ROW zones had significantly higher soil compaction than adjacent unaffected corn planted fields. Tillage to 450 mm depth alleviated the deep soil compaction better than the 300‐mm‐depth tillage as measured by soil cone penetration resistance within the ROW zones and the unaffected zone. These results could be incorporated into agricultural mitigation plans in ROW construction utilities to minimize soil and crop damage. 相似文献
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Influence of Initial Spacing on Growth and Branching Characteristics of Cordia africana Trees Established on Eritrean Highland 总被引：1，自引：0，他引：1
The study reports on the influence of initial spacing on growth and branching habit of Cordia africana trees established on Eritrean highland. The initial spacings used in this study were 1.0×1.0 m, 1.5×1.5 m, 2.0×2.0 m, 2.5×2.5 m,
3.0×3.0 m, and 3.5×3.5 m; these are equivalent to 1 m2, 2.25 m2, 4 m2, 6.25 m2, 9 m2 and 12.25 m2 in growing space per tree, respectively. No significant relationship between spacing and tree height was found, but increased
spacing increased crown diameter and root-collar-diameter. On the other hand, an increase in spacing reduced wood quality
because it increased branch diameter (knot size). Thus, from a wood quality perspective, adopting close spacing in plantations
of C. africana could be advantageous. 相似文献
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