Main Rainy Season Research Articles

Genotypic and Phenotypic Correlation and Path Coefficient Analysis of Rhodes Grass (<i>Chloris gayana</i>) Genotypes

Evidence on the collective association of traits is important for effective selection in forage-breeding program. Twenty four genotypes of Rhodes grass and one check were evaluated at Mechara Agricultural Research Center (Onstation) with lattice design in 2023/24 main rainy season to evaluate the Genotypic and phenotypic correlation and determine the direct and indirect effects of yield-related traits on dry matter yield. The mean sum of squares of genotypes showed significant differences (p < 0.05) for stand vigor, days to 50% emergence, date to 50% flowering and Plant height and highly significant (p < 0.001) for biomass yield, dry matter and number of leaf per plant. Maximum phenotypic variance and genotypic variance value was recorded for days to maturity. The range observed for heritability (H<sup>2</sup>bs) was from (0.0%) to (55%). Stand vigor exhibited highest value of genetic advance as percentage of mean followed by number of leaf per plant. Highest genotypic coefficient variation were recorded from days to maturity (89.8%) flowed by Plant height (62.3%) and Highest phenotypic coefficient variation were recorded from plot cover (184.9%) followed by days to maturity (225.4%). Phenotypically and Genotypically dry matter yield was highly positive significant associated with of Plot cover (0.546**), stand vigor (0.566**), leaf per plant (0.439**) and showed highly negative significant with days to 50% emergence. The results of phenotypic path coefficient analysis showed that stand vigor (0.378) and leaf per plant had exerted moderate positive direct effect on dry matter. stand vigor followed by plant height, plot cover and leaf per plant had exerted high and positive direct effect on dry matter yield and genotypic path analysis showed stand vigor followed by plant height, plot cover and leaf per plant had exerted high and positive direct effect on dry matter yield. This indicates that selection based on these traits could be more effective to maximize dry yield.

Trends and Variability in annual and seasonal rainfall amount and timing in Wereilu district, Northeastern Highlands of Ethiopia

Studying climate change can significantly benefit agricultural practices in a country where many people rely heavily on subsistence farming. To this end, this study aimed to examine trends and variability in rainfall amounts and timing in the climate-vulnerable Wereilu district, northeastern highlands of Ethiopia. The coefficient of variation and standardized rainfall anomaly were employed to analyse rainfall variability, while the Innovative Trend Analysis (ITA) was applied to examine rainfall trends. The findings revealed that Kiremt (main rainy season) exhibited moderate variability, whereas Belg (small rainy season) exhibited high variability. The trend analysis showed significant changes in both seasonal and annual rainfall amounts and their timing. Annual and Kiremt rainfall significantly increased at Wereilu by 55.5 mm and 88.7 mm per decade, respectively, and at Kabie by 16.6 mm and 48.4 mm per decade (p < 0.01). In contrast, Belg rainfall revealed a significant declining trend at both sites. The graphical trend analysis revealed a positive trend for all clusters during Kiremt. In contrast, Belg showed a declining trend across all clusters, with a more pronounced decline in higher values at both sites. Rainfall onset dates significantly shifted towards earlier onset, while rainfall cessation dates showed insignificant late cessation. The length of the rainy season exhibited a positive trend (p < 0.01) at Wereilu and (p < 0.05) at Kabie. Overall, the observed substantial changes in rainfall amounts and timing imply the need for relevant adaptation measures, particularly in the farming system and water sector.

Spatiotemporal variation in grain production performance and efficiency of the cultivated landscapes in Upper Blue Nile Basin of Ethiopia: the impact of residual moisture-based farming on water and food security

Analysis of grain production performance can provide reference information to explore multiple cropping options and further improve the resource use efficiency of farming methods. This study investigated the spatiotemporal dynamics of grain production performance and efficiency of major crop production systems (CPS) in the Ethiopia’s Blue Nile Basin. The results show that only 39% of the basin is currently cultivated, although a significant cropland expansion (10%) was recorded between 1985 and 2020. The study identified 11 major CPS, mostly practiced in the basin. Of these, single cropping based on the main rainy season (Meher-Only) covers the largest area (26%), followed by Meher-Residual-Intermittent (12%) and Meher-Belg-Dependable (11%). Extended-Meher, Meher-Residual-Dependable, Meher-Residual-Intermittent, and Meher-Belg-Dependable are the four more powerful CPS with higher efficiency. Comparatively, CPS practiced in Wet-Woyna-Dega and Wet-Dega have better overall performance. Findings confirm that agricultural space management (land) and green-water (rainfall) utilization are the most influential factors, followed by land use planning and land use systems (CPS) invention. As landscape suitability for grain production governs future performance, in the low elevation and flood plains parts of the basin, the possibility of creating additional space into the food system is very high. In mountainous and high-altitude regions, the efficiency of grain production will decrease because incorporating additional arable land into the food system is trivial. In the last three decades, in BNB, only 10% of arable land (equivalent to 30 million quintals of food) has been added to the good system, which can support approximately 6 million people. Compared to the population growth of the basin (12 million 1985–2020), its contribution to the food system was less than 50%. This confirms that multiple cropping systems, such as Residual moisture-based CPS, have played a significant role in boosting the food system in the basin. Therefore, improving grain production performance/efficiency requires targeted investments, including the invention of more adaptable crop varieties, efficient cropping practices, and the introduction of advanced agricultural space and water management technologies. The results of the study will help identify important policy gaps and suggest possible options to enhance residual farming and other multiple cropping systems.

Agronomic performance and nutritive value of Urochloa species, Desho and Rhodes grass grown in sub-humid central Ethiopia

Improved forage grasses with high quality and biomass are a crucial additional feed source for cereal-livestock farming in Ethiopia. This study compared the performance of 4 Urochloa species [U. brizantha (DZF-13379), U. humidicola (DZF-9222), U. decumbens ‘Basilisk’ (DZF-10871) and U. mutica (DZF-483)] with other 2 commonly used grasses, Rhodes grass (Chloris gayana ‘Massaba’) and Desho grass (Pennisetum glaucifolium local variety Kindu kosha), over 3 years during the main rainy season in Bishoftu in a sub-humid area of Ethiopia. The experiment was conducted using a completely randomized block design. There was significant variation among species for agronomic parameters. The species × year interaction was significant for dry matter yield, plant height, and plot cover but not significant for leaf-to-stem ratio. Nutritional value [ash, acid detergent fiber (ADF), crude protein (CP) and in vitro dry matter digestibility (IVDMD)] was significantly different among species with no differences for neutral detergent fiber (NDF) and acid detergent lignin (ADL). All species showed potential as alternative ruminant feeds with U. mutica and U. brizantha the highest yielding in the sub-humid environment.

Analysis of Meteorological Drought in Cases of North Wello Zone, Ethiopia

Drought is a commonly used term, but the most complex and least realized of all the natural hazards affecting more people than any other hazards. The main objective of the study was to investigate the spatial-temporal occurrence of Meteorological drought indices analysis in the study areas. The study was undertaken to investigate the magnitude, frequency, and trends of drought incidence in North Wello Zone Ethiopia using monthly rainfall records for the period 1990 to 2020 of North Wello zone stations and CHIRPS satellite data. Drought Index Calculator used to analyse standard precipitation index (SPI). The correlation between station data and CHIRPS data in this study was 0.89 which shows highly correlation between them. the result of meteorological drought indices map analysis on the years 1999, 2000, and 2008 severely dry to extremely dry conditions in the Belg season, similarly in 19990, 199308, 201507, 201508, and 201509 have got meteorological drought indices with extremely dry Kiremt season on the North Wello Zone. The drought magnitude of different time scales varied from slight to extremely severe in the studied stations. The identification of the temporal and spatial characteristics of droughts in the North Wello Zone will be useful for the development of a drought preparedness plan in the Zone. Generally increasing tendencies of drought were observed during the main rainy season and decreasing tendencies of drought during the short rainy season and annual scale were observed in the study area.

Effect of harvesting time on root yield and nutritional composition of orange-fleshed sweet potato [Ipomoea batatas (L.) Lam] varieties in East Hararghe

In eastern Ethiopia, sweet potato is a vital food and nutrition security crop; moreover, orange-fleshed sweet potato (OFSP) varieties are rich in beta-carotene content and have the potential to alleviate chronic Vitamin A malnutrition in the region. However, the unavailability of adaptable varieties and lack of information on production and post-harvest handling practices have limited its production and utilization in eastern Ethiopia. The research was conducted to identify the proper harvesting stage of OFSP varieties for optimum yield and nutritional compositions at Rare and Babile research stations of Haramaya University during the main rainy season of 2022. Three varieties (Alamura, Kabode, and Bakule) and four harvesting periods (120, 150, 180, and 210 days after planting (DAP) in factorial combinations were evaluated in randomized complete block design with three replications. Data were collected for growth, yield, and physicochemical composition-related parameters. Combined analysis of variance revealed the interaction effect of harvesting time and varieties had a significant (p < 0.05) effect on yield, yield-related parameters, and physicochemical components. Alamura variety produced comparable above-ground biomass (28.99 t ha−1) and the highest marketable root yield of 36.40 t ha−1 at 150 DAP, with dry matter content of 33.01 and 30.58 % at 150 and 120 DAP, respectively. Harvesting Alamura at 150 DAP also had the highest ꞵ-carotene, zinc, and iron contents of 11809 μg/100 g, 3.79, and 14.47 mg/100 g, respectively. It was concluded that growing the Alamura variety and harvesting at 150 DAP was better for obtaining higher root yield with good nutritional compositions in the study area.

Enhancing Seed Access and Climate Resilience: A Farmer-Based Seed Multiplication Scheme in a Legume-Sorghum Double Cropping System in Mieso District Ethiopia

Sorghum is a major food security crop in Ethiopia. Sorghum landraces are particularly crucial in crop-livestock mixed farming systems in drylands, but due to the longer growing periods (6-8 months) needed for the landraces, the crop faces recurrent drought events associated with delayed rain, dry spells, and drought during critical stages. The landraces are normally grown combining a short and erratic rainy season (March to May) and a main rainy season (July to September). To address such circumstances, early-maturing improved sorghum varieties that are planted in July and mature within 3-4 months have been developed. Moreover, a sustainable cropping system involving legume-early maturing sorghum double cropping has been developed as an alternative to the traditional long-cycle sorghum production to help mitigate crop failure. The legume fits into the short rainy months. However, access to seeds of both component crops could be a challenge. The objective of this study therefore was to establish and assess the feasibility of a farmer-based seed multiplication (FBSM) scheme in enhancing the supply of quality seeds of legumes and sorghum and contributing to climate adaptation. Two activities were implemented in 2015 and 2016 in Mieso district, West Hararghe, Ethiopia. The first activity involved multiplying seeds of two early-maturing and drought-tolerant improved sorghum varieties (Dekeba and Melkam) using a FBSM scheme. The second activity was integrating this scheme into a legume-early maturing sorghum double cropping system. The results of the study show that the FBSM scheme provides much-needed support to smallholder sorghum farmers by offering resources for multiplying and marketing improved sorghum seeds, ensuring seed security, and improving access to quality seeds. The scheme aligns well with the legume-early maturing sorghum double cropping system, thereby enhancing access to compatible seeds and promoting a sustainable cropping system in the region. The scheme presents a viable solution to seed access for smallholder farmers in Ethiopia to enhance seed supply, income, and climate resilience, offering valuable insights for policymakers and stakeholders

Spatiotemporal dynamics of ecosystem services in response to climate variability in Maze National Park and its environs, southwestern Ethiopia.

Climate variability is one of the major factors affecting the supply of ecosystem services and the well-being of people who rely on them. Despite the substantial effects of climate variability on ecosystem goods and services, empirical researches on these effects are generally lacking. Thus, this study examines the spatiotemporal impacts of climate variability on selected ecosystem services in Maze National Park and its surroundings, in southwestern Ethiopia. We conducted climate trend and variability analysis by using the Mann-Kendall (MK) trend test, Sen's slope estimator, and innovative trend analysis (ITA). Relationships among ecosystem services and climate variables were evaluated using Pearson's correlation coefficient (r), while partial correlation was used to evaluate the relationship among key ecosystem services and potential evapotranspiration (PET). The MK tests show a decreasing trend for both mean annual and main rainy season rainfall, with Sen's slope (β) = -0.721 and β = -0.1.23, respectively. Whereas, the ITA method depicted a significant increase in the second rainy season rainfall (Slope(s) = 1.487), and the mean annual (s = 0.042), maximum (s = 0.024), and minimum (s = 0.060) temperature. Spatial correlations revealed significant positive relationships between ecosystem services and the mean annual rainfall and Normalized Difference Vegetation Index (NDVI), while negative correlations with the mean annual temperature. Additionally, temporal correlations highlighted positive relationships among key ecosystem services and the main rainy season rainfall. The maximum and minimum temperatures and ecosystem services were negatively correlated; whereas, there was strong negative correlations between annual (r = -0.929), main rainy season (r = -0.990), and second rainy season (r = -0.814) PET and food production. Thus, understanding the spatiotemporal variability of climate and the resulting impacts on ecosystem services helps decision-makers design ecosystem conservation and restoration strategies to increase the potential of the ecosystems to adapt to and mitigate the impacts of climate variability.

Single and mixed infections of six major potato viruses in four major potato-growing districts of eastern Ethiopia

Potato (Solanum tuberosum L.) is a co-staple food and a source of cash income for the smallholder farmers' in eastern Ethiopia; however, the productivity of the crop is constrained by biotic and abiotic factors. Of which viruses are considered to be major yield limiting factor, but information is lacking on the prevalence and distribution of potato viruses in major growing districts of eastern Ethiopia. This research is therefore initiated to assess and determine the status of six major and multiple potato viruses' infection at farmers' fields during the main rainy and irrigation seasons in four major potato-growing districts of eastern Ethiopia. The dot-blot assays performed for 1000 leaf samples collected from 20 farmers' fields during the two seasons indicated an overall high incidence (71.9% samples detected positive for at least one virus) of potato virus in the surveyed districts of the regions. The most prevalent (19.4%) type of infection was the mixture of all six potato viruses. Among the major viruses, the results also confirmed PVM as the most prevalent (57.3%) virus followed by PVY (48.1%), whereas PVA (45.1%), which was not commonly detected in the other regions of the country, was detected as third most prevalent virus in the current study. The comparison of the results of virus detection in the samples from two seasons indicated remarkable differences in the incidence and prevalence of viruses, where an increasing trend of virus incidence and mixed virus infections from 59 to 84.8% and 41.2 to 72%, respectively, were recorded from rainy to irrigation season. The two viruses; PVX and PVS, which were identified as least prevalent during rainy season, were ranked the 3rd and 4th most prevalent viruses after PVM and PVY during irrigation season. The detected high incidence of virus in potato plants during this first systemic research conducted suggested the importance of continuing the intensive survey and detecting the status of viruses' infection in potato growing districts of eastern Ethiopia. It is also suggested to create awareness among smallholder farmers about the management practices to reduce the effects of viruses’ infection on the productivity of potato in eastern Ethiopia.

Improved mapping of highland bamboo forests using Sentinel-2 time series and machine learning in Google Earth Engine

Recent advances in the application of spectral bands from satellite observations and machine learning algorithms (MLA) in the Google Earth Engine (GEE) cloud-computing platform have been demonstrated to enhance the accuracy of mapping forest resources. This study presents a novel method for mapping the natural distribution of highland bamboo (Oldeania alpina) using spectral bands and three machine learning algorithms, namely random forest, gradient tree boosting, and classification and regression tree. First, spectral bands, vegetation indices and textural features including contrast, entropy and inverse difference moment were derived from the Sentinel-2 elevation data. Second, observations were categorized as the dry season (December–February), short rainy season (March-May), main (long) rainy season (June-August), wet season (September–November) and annual composite. Third, the machine learning algorithms were tested using 1882 ground control points collected from field and high spatial resolution images. Finally, the best-performing machine learning algorithm was used to classify and map bamboo forests. The five land cover categories identified were bamboo stands, natural forest, other vegetation, non-vegetated areas and water bodies. The result shows that the random forest classifier is a robust algorithm with an overall accuracy of 94% considering all the annual composite’s spectral, vegetation and textural variables. The highland bamboo coverage (91 km2) in the Andracha district provided valuable insights. Bamboo stands were mostly distributed in the southern and southeastern parts of the district. Here, we show that image compositing and multiple input parameters using machine learning techniques can overcome challenges facing land cover classification, which can hinder accurate mapping of Afromontane forests. We conclude that the incorporation of vegetation indices and textural features in land cover classification increases accuracy of mapping natural highland bamboo coverage and distribution. The application of this new method is a promising prospect not only in Ethiopia but also in Afromontane forests elsewhere in Africa.

Appropriate seed source and rate enhanced the productivity of bread wheat varieties under irrigated conditions in North Mecha, Amhara region, Ethiopia

Bread wheat is a strategic cereal crop produced ndederunder both irrigation and main rainy season in the Amhara region, Ethiopia. However, its productivity is low due to unreliable seed sources, inappropriate seed rate, and unavailability of adaptable improved varieties for a wide range of agro-ecologies. Therefore, an experiment aimed at evaluating the influence of seed sources, rates, and varieties on yield and yield-related traits under irrigated conditions was conducted during 2021 at North Mecha, Amhara region, Ethiopia, to provide information and knowledge for bread wheat researchers and producers. The experiment was laid out in a randomized complete block design with three replications in a factorial arrangement of two varieties (Kakaba and Ogolcho), three seed sources (Ethiopia Seed Enterprise (ESE), Ediget Bandinet Seed Producing Cooperative Union (EBSPCU), and farmers with three seed rates (125, 150, and 175 kg ha-1). Basic agronomic and yield data were collected. The data were analyzed using SAS software. The results showed that productive tiller numbers, 50 % heading, number of kernels per spike, and plant height were significantly influenced by the interaction of seed source with variety. Interaction of variety with seed rate had also significantly influenced productive tiller number and 50 % heading. The highest grain yield (4.99 t/ha) was recorded on Kakaba variety sourced from Ediget Bandinet seed producing union sown at a rate of 150 kg ha−1 followed by Ethiopia seed enterprise (4.31 t ha−1) sown at the same seed rate. Kakaba seeds sourced from farmers produced the least grain yield. Therefore, using Kakaba seeds from the formal seed system like Edget Bandinet seed producing union sown at a rate of 150 kg ha−1 could be recommended to increase the productivity of bread wheat under irrigated condition in north Mecha. It is also necessary to conduct experiments considering a greater number of seed sources, seed rates, and varieties in more than one cropping season and location to strengthen the current result.

First Record of Milk thistle (&lt;i&gt;Silybum marianum&lt;/i&gt;, Asteraceae) as Invasive Weed Species in Urban Green Areas of Addis Ababa City, Ethiopia

With increasing globalization and trade, the rate of invasive species entering and spreading has significantly increased globally. These include various invasive insect pests, pathogens, and weeds. Since three years ago, Milk thistle, Silybum marianum, an invasive weed species, has been observed widely in urban green spaces and roadsides in Addis Ababa city, Ethiopia. Weed surveys were conducted across 42 urban green sites located in Yeka, Lemi Kura, Bole, Nifas Silk-Lafto, Kolfie Keraniyo, Akaky Kality, and Gullele sub-cities during the main rainy season from June to September 2023, with the main objective of determining the current distribution of the weed in Addis Ababa city. The urban green areas were selected by using purposive sampling techniques. Field observations confirmed that Silybum marianum can invade and colonize wide habitats and is a highly competitive invasive weed to other important native plant species. High weed density rates and dense stands of weeds were recorded in the 34 urban green areas sampled. The survey result strongly suggests fast integrated weed management options such as mowing/tilling, weeding before the plant goes to seed, cutting (stems and/or seed heads), and burning (collected plant parts and/or seed heads) into a prepared burrow were done to minimize the spreading of the weed and its ecological impacts. The purpose of this survey study is to provide information about Silybum marianum to minimize or avoid its distribution and associated impacts by following sustainable invasive weed management programs in the city before spreading to other cities in the country.

Evaluation of water quality and trophic status in relation to seasonal water mixing in a highland Lake Ardibo, Ethiopia.

The aim of the present study was to evaluate the spatio-temporal variability of various physical and chemical parameters of water quality and to determine the trophic state of Lake Ardibo. Water samples were collected from October 2020 to September 2021 at three sampling stations in four different seasons. A total of 14 physico-chemical parameters, such as water temperature, pH, dissolved oxygen (DO), electrical conductivity, turbidity, alkalinity, Secchi-depth, nitrate, ammonia, silicon dioxide, soluble reactive phosphorus, total phosphorus, chloride, and fluoride were measured using standard methods. The results demonstrated that temporal variation existed throughout the study period. Except for turbidity, the water quality of the lake varied significantly within the four seasons (ANOVA, p < 0.05). DO levels decreased significantly during the dry season following water mixing events. Chlorophyll-a measurements showed significant seasonal differences ranging from 0.58 μg L-1 in the main-rainy season to 8.44 μg L-1 in the post-rainy period, indicating moderate algal biomass production. The overall category of Lake Ardibo was found to be under a mesotrophic state with medium biological productivity. A holistic lake basin approach management is suggested to maintain water quality and ecological processes and to improve the lake ecosystem services.

The first record of milk thistle (Silybum marianum, Asteraceae) as an alien invasive weed species in Addis Ababa City, Ethiopia.

Abstract Since 2020, milk thistle Silybum marianum, an invasive weed species, has been widely observed in urban green spaces and roadsides in Addis Ababa city, Ethiopia. To plan future management activities, this study aimed to determine the current distribution status of the weed in urban green areas of Addis Ababa city. Weed surveys were conducted across 42 urban green sites located in Yeka, Lemi Kura, Bole, Nifas Silk-Lafto, Kolfie Keraniyo, Akaky Kality, and Gullele sub-cities during the main rainy season from June to September 2023. Urban green areas were selected using purposive sampling techniques. Field observations confirmed that Silybum marianum can invade and colonize a wide range of habitats and is highly competitive, posing a threat to important native plant species. High weed density rates and dense stands of weeds were recorded in the 34 urban green areas surveyed. The survey results strongly suggest implementing fast integrated weed management options such as mowing/tilling, weeding before the plant goes to seed, cutting (stems and/or seed heads), and burning (collected plant parts and/or seed heads) into a prepared burrow to minimize the spread of the weed and its ecological impacts. The purpose of this survey study is to provide information about Silybum marianum to minimize or avoid its distribution and associated impacts by following sustainable invasive weed management programs in the city before spreading to other cities in the country.

Spatiotemporal analysis of drought severity using SPI and SPEI: case study of semi-arid Borana area, southern Ethiopia

Drought is a complex natural hazard that can cause damage to socio-economic and biophysical systems in any climatic region. The main objective of this paper was to analyze the spatiotemporal drought in the semi-arid Borana area of southern Ethiopia from 1981 to 2018. The climate data was obtained from the Ethiopian Meteorological Institute. Standardized precipitation index (SPI) and Standardized Precipitation Evapotranspiration Index (SPEI) at 3- and 12-month timescales were adopted to characterize drought during these periods and wet seasons in time and space. The results revealed that moderate to extreme drought conditions at various stations frequently hit months stretching from March to June and September to November. The years 1984, 1985, 1992, 1999, 2000, 2001 and 2011 were known to be the driest years, among others. A total of 484, 563, 573 and 620 combined moderate, severe and extreme drought events were observed across all stations using SPI-3, SPEI-3, SPI-12 and SPEI-12, respectively. Internal variability among the stations was noticed regarding the frequency and magnitude of drought. Ganna (March to May), the season that was supposed to be the main rainy season in the region, was by far drier than Hagayya (September to November), the short rainy period. In general, this study found a high frequency and intense magnitude of drought that varies across the stations. Therefore, any localized adaptation and mitigation strategies intended to tackle or minimize drought-associated impacts should take into account this local variability.

Adaptation of Napier grass varieties in the highlands of East Gojjam

The experiment was conducted in the East Gojjam Zone of the Amhara Regional State to evaluate the varieties of released Napier grass in the study area. The four varieties of Napier grass considered for this research experiment were Maralfalafa, ILRI- 16743, ILRI-14984 and Zehone-03 (Acc. 16819). The varieties were planted in 4 m x 3 m plots using a randomized complete block design (RCBD) with three replications at the beginning of the main rainy season. Root splits at the Debremarkos onstation and Debere Eliyas sites were planted in four rows per plot. The analysis was conducted using R software. Least significance difference (LSD) at the 5% significance level was used for the comparison of means. The combined plant height, number of tillers per plant, total fresh biomass yield per hectare (t/ha), and total dry matter yield (t/ha) did not significantly differ between the varieties. The leaf-to-stem ratios of the Napier grass varieties were significantly different. In the present study, ILRI-14984 was found to be leafier than the other tested varieties. The combined analysis of the second- and third-year data revealed significant differences in plant height, number of tillers and leaf-to-stem ratio among the tested years. The greatest plant height (152.42 cm) at harvest was found in the second year after establishment, which was 2022, whereas the number of tillers per plant was greater in the 2023 harvest season. The testing location did not affect plant height, total fresh biomass yield per hectare, or total dry matter yield per hectare. The number of tillers per plant and the leaf-to-stem ratio significantly differed among the tested locations. A greater number of tillers per plant was recorded at the Debre Eliyas testing site. Similarly, the leaf-to-stem ratio was significantly greater at the same testing site.

Evaluation of Blended NPSB Fertilizer on Yield and Yield Components of Barley (Hordeum vulgare L.) under Rain-fed Condition at Cheguarkudo in Tsegedie District Western Tigray, Ethiopia

Field experiment was conducted with the objective of evaluating the effects of blended (NPSB) fertilizer rates on yield and yield components of Barley at Cheguarkudo in Tsegedie Wereda of Tigray Ethiopia during the main rainy seasons of 2019 and 2020. The experiment was carried out on farmers' field with three replications using randomized complete block design (RCBD), comprised of 8 treatments 0, 50, 100, 150, 200, 250, 300 kg/ha NPSB and recommended NP 64kg/ha N and 46 kg P2O5/ha. Composite soil samples were also initially collected from 0-20 cm depth of the fields and analyzed. The blended fertilizer rates were applied at the time of sowing while N was applied in split into two applications. Phosphorus di ammonium phosphate (DAP) was also applied at planting time. Plant height, spike length, straw yield, grain yield data were collected. Soil analyses of the experimental fields revealed sandy loam soil textural classes, strongly acid soil reaction (pH), low organic matter (OM), low total N and low Olsen P. Application of different rates of NPSB fertilizers significantly (P≤0.05) and positively influenced most of the crop parameters. Highest result was obtained at 300 kg/ha blended. Partial budget analysis showed highest and profitable yield at 150 kg NPSB/ha was recorded for Barley. This profitable rate could be recommended for the experimental area.

Analysis of the genotype through interactions with the environment and dry matter yield stability of Lablab purpureus L. in midland of Guji zone.

Abstract The purpose of the study was to assess Lablab genotyping performance in different Guji midland areas. A 3mx2m plot was used to seed twelve accessions of Lablab purpureus , which were obtained from the International Livestock Research Institute Gene Bank, and a tick registered variety from Bako Agricultural Research Centre. During the main rainy season in 2021-2022, three locations-Dufa, Gobicha, and Kiltu sorsa, Adola subsite, and on farms in two (2) consecutive years, respectively were studied using randomized complete block designs (RCBD) with three replications. Information was gathered regarding the establishment, duration of various physiological stages, dry matter yield of fodder, chemical compositions, and additional relevant factors. AMMI and the SAS statistical analysis programmer, version (2002), were used to perform an analysis of variance on the gathered data. The list significant difference test was used to compare the means. The results of the AMMI analysis of variance for forage dry matter yield showed that there were substantial (P &lt; 0.01) variations in genotype and environment, but not in the effects of the G x E interaction. Both the representative testing site and the testing conditions (Adola Woyu and Kiltu Sorsa) were quite good at differentiating genotypes. The combined analysis data revealed non-significant (P &gt; 0.05) differences for plant height and thousand seed weight, but significant (P ≤ 0.05) differences for days to flowering, days to maturity, number of branches, leaf to steam ratio, number of pods, and number of seeds across the tested environments. The results showed that, out of all the examined locations, G-11620 (15.43 t/ha) and G-14486 (11.12 t/ha) had the highest forage dry matter production. It was observed that the leaf to steam ratio was higher in both G-11486 and G-11620. All chemical compositions across tested genotypes were found to be significantly different (p ≤ 0.05) in the study of composite chemical compositions, with the exception of DOMD and IVDMD, which did not reveal significant (p &gt;0.05) variations among genotypes. The recorded CP content ranged from 21.15% for G-14486 to 23.50% for G-11620, with the lowest value coming from typical cheek Gabis 10.8%. The highest and the lowest NDF were recorded from G-11620 (11.2%) and Gabis (22.23%) respectively. Generally the mean performance, yield and stability of the G-11620 and G-14486 were high and stable across the tested locations. Therefore, genotypes (G-14486 and G-11620) were promoted to VVT for further evaluation and possible for release.

Local and regional climate trends and variabilities in Ethiopia: Implications for climate change adaptations

Ethiopia is experiencing considerable impact of climate change and variability in the last five decades. Analyzing climate trends and variability is essential to develop effective adaptation strategies, particularly for countries vulnerable to climate change. This study analyzed trends and variabilities of climate (rainfall, maximum temperature (Tmax), and minimum temperature (Tmin)) at local and regional scales in Ethiopia. The local analysis was carried out considering each meteorological station, while the regional analyses were based on agro-ecological zones (AEZs). This study used observations from 47 rainfall and 37 temperature stations obtained from the Ethiopian Meteorological Institute (EMI) for the period of 1986 to 2020. The Modified Mann-Kendall (MMK) trend test and Theil Sen's slope estimator were used to analyze the trends and magnitudes of change, respectively, in rainfall as well as temperature. The coefficient of variation (CV) and standardized anomaly index (SAI) were also employed to evaluate rainfall and temperature variabilities. The local level analysis revealed that Bega (dry season), Kiremt (main rainy season), and annual rainfall showed increasing trend, albeit no significant, in most stations, but the rainfall in Belg (small rainy) season showed a non-significant decreasing trend. The regional levels analysis also indicated an increasing trend of Bega, Kiremt, and annual rainfall in most AEZs, while Belg rainfall showed a decreasing trend in the greater number of AEZs. The result of both local and regional levels of analysis discerned a spatially and temporally more homogeneous warming trend. Both Tmax and Tmin revealed an increasing trend in annual and seasonal scales at most meteorological stations. Likewise, an increase was recorded for mean Tmax and Tmin in entire/most AEZs. The observed trends and variabilities of rainfall and temperature have several implications for climate change adaptations. For example, the decrease in Belg rainfall in most AEZs would have a negative impact on areas that heavily depend on Belg season's rainfall for crop production. Some climate adaptation options include identifying short maturing crop varieties, soil moisture conservation, and supplemental irrigation of crops using harvested water during the main rainy season. Conversely, since the first three months of Bega season (October to December) are crop harvest season in most parts of Ethiopia, the increase in Bega rainfall would increase crop harvest loss, and hence, early planting date and identifying short maturing crops during the main rainy season are some climate adaptation strategies. Because of the increase in temperature, water demand for irrigation during Bega season will increase due to increased evapotranspiration. On the other hand, the increase in Kiremt rainfall can be harvested and used for supplemental irrigation during Bega as well as the small rainy season, particularly for early planting. In view of these findings, it is imperative to develop and implement effective climate-smart agricultural strategies specific to each agro-ecological zone (AEZ) to adapt to rainfall and temperature changes and variabilities.

External Forcings Caused the Tripole Trend of Asian Precipitation During the Holocene

AbstractTo investigate the evolution of precipitation over Asian continent in the Holocene and the associated mechanisms, we used a set of simulations of the transient climate evolution over the past 21,000 years (TraCE‐21ka), multimodel results from the Paleoclimate Modeling Intercomparison Project Phase 4 (PMIP4), and proxy records in Asia. The TraCE‐21ka results showed a tripole pattern in suborbital‐scale precipitation trends over the Asian continent during the Holocene, with a trend of increase over southern parts of the monsoon regions and arid Central Asia (ACA), and a trend of decline over northern parts of the monsoon regions and their areas of transition with ACA. This tripole pattern was corroborated by proxy records from multiple regions and multimodel results from the PMIP4. Further analysis based on single‐forcing simulations of TraCE‐21ka indicated that influences from different external forcings were different on the Asian precipitation in the main rainy seasons in the Holocene and that their combined effects shaped the tripole pattern. In summer, orbital forcing, by reducing solar radiation in mid‐to‐high latitudes and weakening the land‐sea thermal contrast, has been the dominant factor in the long‐term evolution of precipitation in the monsoon region and West Asia. In winter and spring, changes in meltwater flux played dominant roles in intensifying local water cycle and horizontal moisture advection, which drove the trend of increase in precipitation in ACA. Additionally, changes in greenhouse gas concentration and continental ice sheet forcings both also contribute to the increase in precipitation in ACA.