Adaptation and growth performance of five avocado cultivars in Ethiopia.

Ethiopia has diverse agroecology with vast areas, suitable for growing subtropical and tropical fruits. Despite this potential, the avocado industry in Ethiopia is still in its infancy. This study assessed the adaptation of five avocado cultivars: Ettinger, Fuerte, Hass, Nabal, and Reed, survival rate, growth performances, fruit yield, and household contributions in Lemo district Ethiopia. The results revealed that there were significant differences in tree growth performance and yield among avocado cultivars (P < 0.05). The highest vegetative growth performance was demonstrated by Nabal, Fuerte, Ettinger, and Hass, while Reed was the lowest. In 2020, Nabal had the highest fruit yield (96 kg tree1), followed by Hass (47 kg tree1), while Fuerte had a relatively low fruit yield (39.43 kg tree1). Due to its larger fruit size, the Nabal was used for sale, while the Hass cultivar, which has a sweet taste, was mainly used for home consumption. The findings demonstrated that significant difference in management practices applied by male and female farmers. Overall, the study concluded that the Nabal, Hass, and Ettinger cultivars had a great potential for fruit production, which could improve smallholder farmers livelihood. As a result, it is necessary to scale up these avocado cultivars in the midland agroecological zone of the country.

Animal welfare knowledge, attitudes, and practices among livestock holders in Ethiopia.

Improving animal welfare is a human responsibility and influenced by a person's values and experiences. Thus, it is critical to have an in-depth understanding of the knowledge, attitudes, and practices (KAP) of animal welfare among animal owners. For livestock in Ethiopia, the greatest proportion of livestock are reared by pastoral and mixed crop-livestock communities. A cross-sectional survey covering a range of species and animal welfare aspects was carried out on a total of 197 household (117 pastoral and 80 crop-livestock owners) and recorded information on 34 animal welfare KAP items. Item response theory models (IRT) were fitted to the data from KAP items to estimate the probability of correctly answering an item. This was used as a function of the respondents' KAP level. Overall, the highest percentage of desirable scores was recorded for the knowledge scale (35.7%) and the lowest was for the practice scale (24.6%). A significant correlation (P < 0.01) was found between knowledge of the farmers and their attitude toward animal welfare and self-reported practices. Generally, households practicing mixed crop-livestock farming system had better animal welfare knowledge, attitude, and practice than pastoralist. Mixed crop-livestock farmers had better knowledge on items related to observing the nutrition condition of the animal, animal-human relationship, the importance of water, and health inspection compared to pastoralists. In contrast, pastoralists had better knowledge of items related to natural behavior expression, animal care, and animal suffering than mixed crop-livestock farmers. Pastoralists had 3.3-times higher odds than mixed crop-livestock farmers to have a positive attitude to train their animals without beating. KAP scores demonstrate the need for targeted training to improve animal well-being (i.e., housing, management, nutrition, disease prevention and treatment, responsible care, humane handling) across livestock holding communities in Ethiopia.

Nutritional and ecoclimatic importance of indigenous and naturalized wild edible plant species in Ethiopia.

Wild edible plant species (WEPs) are sources of food, nutrition, and medicine to people. However, often, the nutritional value of WEPs is unknown. This study was conducted to determine proximate and mineral contents of Balanites aegyptiaca, Cordia africana and Ziziphus spina-christi fruit. Fruit samples were collected from 10 trees of each species from Northern and Rift Valley region of Ethiopia. Fruit samples from the same species and district were mixed to form a composite sample, then dried, ground to powder and used for chemical analysis. We found a comparable amount of mean crude protein contents in C. africana and B. aegyptiaca. The fiber content was higher in B. aegyptiaca and Z. spina-christi. Carbohydrate and energy content were higher in Z. spina-christi compared to other study species. We found higher values of calcium in B. aegyptiaca and Z. spina-christi potassium, iron and zinc contents of B. aegyptiaca and C. africana, exceeded the value found in Z. spina-christi by about 50%. Our findings confirmed that the studied food tree species are potential sources of macronutrients and minerals. Therefore, promoting their sustainable use and increasing their abundance on different landscapes through Agroforestry system is critical to improve food availability and landscape resilience to climate change impacts.

Volume estimation models for avocado fruit.

Avocado (Persea americana Mill.) is an important horticultural crop and proved to be a very profitable commercial crop for both local consumption and export. The physical characteristics of fruits are an important factor to determine the quality of fruit produced. On the other hand, estimation of fruit volume is time-consuming and impractical under field conditions. Thus, this study was conducted to devise cultivar-specific and generalized allometric models to analytically and non-destructively determine avocado fruit volume of five wildly distributed avocado cultivars. A significant relationship (P ≤ 0.01) was found between fruit diameter, length, and volume of each cultivar. Our best models (VM2 -for cultivar specific, and VM7-generalized model) has passed all the rigorous cross-validation and performance statistics tests and explained 94%, 92%, 87%, 93%, 94% and 93% of the variations in fruit volume of Ettinger, Fuerte, Hass, Nabal, Reed, and Multiple cultivars, respectively. Our finding revealed that in situations where measurements of volume would be inconvenient, or time-consuming, a reliable volume and yield estimation can be obtained using site- and cultivar-specific allometric equations. Allometric models could also play a significant role in improving data availability on avocado fruit physical appearance which is critical to assess the quality and taste of fresh products influencing the purchase decision of customers. Moreover, such information can also be used as a ripeness index to predict optimum harvest time important for planned marketing. More importantly, the models might assist horticulturists, agronomists, and physiologists to conduct further study on avocado production and productivity through agroforestry landuse system across Ethiopia.

Multi-century tree-ring precipitation record reveals increasing frequency of extreme dry events in the upper Blue Nile River catchment.

Climate-related environmental and humanitarian crisis are important challenges in the Great Horn of Africa (GHA). In the absence of long-term past climate records in the region, tree-rings are valuable climate proxies, reflecting past climate variations and complementing climate records prior to the instrumental era. We established annually resolved multi-century tree-ring chronology from Juniperus procera trees in northern Ethiopia, the longest series yet for the GHA. The chronology correlates significantly with wet-season (r = .64, p < .01) and annual (r = .68, p < .01) regional rainfall. Reconstructed rainfall since A.D. 1811 revealed significant interannual variations between 2.2 and 3.8 year periodicity, with significant decadal and multidecadal variations during 1855-1900 and 1960-1990. The duration of negative and positive rainfall anomalies varied between 1-7 years and 1-8 years. Approximately 78.4% (95%) of reconstructed dry (extreme dry) and 85.4% (95%) of wet (extreme wet) events lasted for 1 year only and corresponded to historical records of famine and flooding, suggesting that future climate change studies should be both trend and extreme event focused. The average return periods for dry (extreme dry) and wet (extreme wet) events were 4.1 (8.8) years and 4.1 (9.5) years. Extreme-dry conditions during the 19th century were concurrent with drought episodes in equatorial eastern Africa that occurred at the end of the Little Ice Age. El Niño and La Niña events matched with 38.5% and 50% of extreme-dry and extreme-wet events. Equivalent matches for positive and negative Indian Ocean Dipole events were weaker, reaching 23.1 and 25%, respectively. Spatial correlations revealed that reconstructed rainfall represents wet-season rainfall variations over northern Ethiopia and large parts of the Sahel belt. The data presented are useful for backcasting climate and hydrological models and for developing regional strategic plans to manage scarce and contested water resources. Historical perspectives on long-term regional rainfall variability improve the interpretation of recent climate trends.