Evaluation of common wheat cultivars for tan spot resistance and chromosomal location of a resistance gene in the cultivar 'Salamouni'

A total of 50 wheat (Triticum aestivum L.) cultivars were evaluated for resistance to tan spot, using Pyrenophora tritici‐repentis race 1 and race 5 isolates. The cultivars ‘Salamouni’, ‘Red Chief’, ‘Dashen’, ‘Empire’ and ‘Armada’ were resistant to isolate ASC1a (race 1), whereas 76% of the cultivars were susceptible. Chi‐squared analysis of the F₂ segregation data of hybrids between 20 monosomic lines of the wheat cultivar ‘Chinese Spring’ and the resistant cultivar ‘Salamouni’ revealed that tan spot resistance in ‘Salamouni’ was controlled by a single recessive gene located on chromosome 3A. This gene is designated tsn4. The resistant cultivars identified in this study are recommended for use in breeding programmes to improve tan spot resistance in common wheat.     

Understanding farmers’ potato production practices and use of improved varieties in Chencha,Ethiopia

This study was carried out to better understand non-adoption of improved varieties of potato (Solanum tuberosum) and associated technologies by smallholder farmers in Chencha, Ethiopia. Data were collected through a survey (n = 47) and in-depth interviews (n = 20). It shows how wealth status was a factor of major importance. Most wealthy and some medium-wealthy farmers adopted improved potato varieties and many of the improved production practices; they had access to seed, associated knowledge and support, and sufficient resources that were necessary to apply the improved practices. Non-adoption was common among many medium-wealthy and most poor farmers: they lacked—next to access to the technologies and knowledge—cash, land, and labor. Results indicated the need to rethink research and intervention efforts. Next to paying attention to differences in the access to technology and the related knowledge, there is a need to consider the variation in technology needs, supporting microcredit services, and room to experiment. As a result, different combinations of improved production practices may be adopted.     

A comparative assessment on regeneration status of indigenous woody plants in Eucalyptus grandis plantation and adjacent natural forest

Diversity, density and species composition of naturally regenerated woody plants under Eucalyptus grandis plantation and the adjacent natural forest were investigated and compared. Twenty plots, with an area of 20 m × 20 m for each, were established in both of E. grandis plantation and adjacent natural forest, independently. In each plot, species name, abundance, diameter and height were recorded. Numbers of seedling were collected in five sub-plots (4 m²) within each major plot. A total of 46 species in the plantation, and 52 species in the natural forest, which belongs to 36 families were recorded. The diversity of species (H′) is 2.19 in the plantation and 2.74 in the natural forest. The density of understory woody plant was 3842 stems/ha in the plantation and 4122 stems/ha in the natural forest. The densities of seedlings in the natural forest and the plantation were 8101 stems/ha and 4151 stems/ha, respectively. High similarity of woody species composition was found between the natural forest and the plantation. The E. grandis plantation was found favoring the regeneration and growth of Millitia ferruginia and Coffea arabica in a much better way than other underneath woody species.     

Genome wide association study of grain yield and yield related traits in spring bread wheat (Triticum aestivum L.) under drought and heat conditions in three different locations

Journal of Crop Science and Biotechnology - Abiotic stress, especially drought and heat, affects cereal yields and wheat production worldwide, more particularly in West and South Asia, North...     

Nutritive characterization of purslane accessions as influenced by planting date

The uniqueness of purslane (Portulaca spp.) asthe richest vegetable source of omega-3 (-3)fatty acids is well documented. However, purslane hasnot been domesticated or fully evaluated for itsnutritive value. The objective of this study was todetermine the influence of planting date on chemicalcomposition of purslane accessions. Eight accessionsfrom different geographical locations were planted 12days apart, and whole plants harvested at full bloom. Chemical analysis (DM basis) of leaves showedsignificant differences among varieties for all thecharacteristics measured. Accession by planting dateinteraction influenced (p < 0.05) levels of crudeprotein, total lipids, and carbohydrate contents. Wild Greek accession had the highest, while aBeltsville (Maryland) wild type had the lowest crudeprotein content (27.1 vs 20.5%) at the secondplanting date. Crude protein, lipid and ash levelswere most influenced (p < 0.05) by planting date. Total lipids varied from 4.0–5.8% and 3.7–5.1% forthe first and second planting dates, respectively. Selected fatty acid content indicated significantly(p < 0.05) higher levels of 18: 26, and18: 33 in the Dutch Garden accession comparedwith other varieties. The Egyptian wild accession hadthe lowest level of 18: 33. The ratio of 3 to 6 acids, which ranged from 5.5 to22.3 indicated a highnutritive value of purslane compared to other oilcrops such as soybeans and perrilla. The high levelsof protein in purslane compete with those of othercommercially important vegetable crops. The studyshows that, in spite of its genetic diversity, purslaneremains one of the most abundant terrestrial vegetablesources of Omega-3 fatty acids and other essentialnutrients potentially beneficial for humans as well asanimals.     

Fusarium head blight progression and yield response of bread wheat as affected by fungicides and spray regimes under field condition in southern Ethiopia

Journal of Crop Science and Biotechnology - Fusarium head blight (FHB) is one of the destructive diseases in wheat-producing areas of the world. Field experiments were conducted during the 2019...     

The Effect of Different Planting Dates on the Infestation of Soybean by Heterodera glycines Race 5

The effects of different planting dates on infestation of susceptible soybean cvs. Essex and Lee by Heterodera glycines were investigated during three growing seasons. Early planting dates of susceptible soybean cvs. at lower temperatures resulted in smaller nodules, lower nematode populations and field infestations, lower soybean cyst nematode (SCN) disease ratings, taller plants, and higher yields. SCN induced more nodules on soybean roots at 14 May plantings date. The development of SCN race 5 in the field was associated closely with soil temperature. The infestation of susceptible soybean cvs. at early planting dates by H. glycines greatly affected the agronomic performance of these cvs. in the field. Susceptible soybean cvs grown in infested soil with SCN race 5 planted earlier than the recommended planting dates escaped severe infestation of SCN in the field.     

Study on Coccidiosis of Scavenging Indigenous Chickens in Central Ethiopia

An investigation was made into coccidiosis of 190 scavenging indigenous chickens between September 2000 and April 2001 in three selected agroclimatic zones, in central Ethiopia. This was done through clinical, postmortem and microscopic examinations. Data were processed by chi-square and Mantel-Haenzel test. The study indicated that 25.8% (49/190) of the chickens were infected with coccidiosis and found to harbour one to four different species of Eimeria. Of these infected chickens, 30 (15.8%) and 19 (10.0%) were positive for clinical and sub-clinical coccidiosis, respectively. There was a significant altitude difference (chi2 = 14.7, p <0.001) in coccidiosis prevalence: 42.2% in chickens from highland region followed by 21.5% in mid-altitude and 13.1% in low-altitude areas. When quantified, the prevalence of coccidiosis was 2.66 and 4.83 times higher in the high-altitude than in mid-altitude (odds ratio, OR = 2.66, p<0.05) and low-altitude (OR = 4.83, p<0.001) chickens. The pathogenic Eimeria species responsible for clinical coccidiosis were E. necatrix, E. acervulina, E. maxima and E. tenella. With increasing demand for poultry products in developing countries, knowledge of production constraints in traditional management practices could help devise control strategies for constraints on backyard poultry production systems.