Propagation Techniques for Highland Bamboo (Arundinaria alpina) in the Choke Mountain, Northwestern Ethiopia

With the aim of identifying improved propagation techniques that can be applied in a larger scale plantation, six types of vegetative propagation materials obtained from three A. alpina landraces (TIFRO, WELELE and WONDE) were evaluated for their performance under field condition in the Choke Mountain, northwestern Ethiopia. The three techniques namely stump, rhizome and whole-culm had fastest shoot emergence (21-22 days) and superior performance during the four Months period After establishment (MAE).Shoot height was 262, 233 and 193 cm for stump, rhizome and whole-culm with respective to diameter at breast height of 1.0, 1.1 and 1.5 cm 4 MAE, respectively. The whole-culm method also produced the maximum number of shoots (10 new shoots per propagule), along its stem length (at the upper, middle and butt positions excluding its lower one-third portion) but branch cuttings and culm cuttings had slow shoot emergence (average 30 days) and very poor performance. In general, TIFRO and WELELE landraces had faster shoot emergence (21-23 days) and significantly higher number of new shoots than WONDE landrace. Shoot emergence of the offset (traditional) method was delayed up to the next shooting season (11 MAE) but its performance, including survival rate of the propagules (85%), was superior at that season. New shoots from stump, rhizome and whole-culm were found to be prone (survival rate 17-26%) primarily to strong wind and storm and most probably moisture fluctuations under field condition after four months period hence further research on silvicultural practices that can maximize their persistence is required.Keywords: cuttings, landraces, offset, rhizome-based propagation, Yushania alpin

The effect of silvicultural management on regeneration, growth and yield of Arundinaria alpina (Highland bamboo) at Choke Mountain, East Gojam, Northwest Ethiopia

With the objective of determining the effects of silvicultural management on regeneration and growth of mismanaged Arundinaria alpina stands, an experiment was conducted in the Choke Mountain, northwest Ethiopia. Eight soil and plant management techniques that comprise soil loosening, selective thinning and removal of old stumps were splited on two levels of organic fertilizer and applied on one hectare communally owned bamboo stand. Effect of the treatments was observed from data collected in 2009 and 2010 rainy seasons. The number of recruited culms of previous years (2007 and 2008) which had intermittent protection from human and livestock interference was also quantified employing culm age determination techniques. Result of combined analysis of 2009 and 2010 indicated that soil loosening combined with selective thinning and removal of old stumps resulted in culm recruitment of 13,750 plants ha-1, i.e. 37% higher than the control plot. This treatment combination decreased shoot mortality by 61% less than the control and increased culm recruitment by 40 % more than the control plot during the 2009 shooting season. Culm diameter and height of individual culms recruited in 2009 and 2010 showed increasing trend across the two years. Comparison of culm recruitment of previous years with recruitments after treatment application indicated that with improved management, including protection from interference, culm yield of communally owned bamboo stands can be maximized by 158-589%.Keywords: soil loosening, selective thinning, highland bamboo, silviculture, Yushania alpin

Effect of drought/irrigation on proximate composition and carbohydrate content of two enset [Ensete ventricosum (Welw.) Cheesman] clones

Enset [Ensete ventricosum (Welw.) Cheesman] is an important root crop serving as a carbohydrate rich food source in Ethiopia. Perennial crops, like enset, are often exposed to recurrent dry periods which could greatly affect their growth, physiology and yield. The effect of induced drought/irrigation on the proximate composition and carbohydrate content of harvestable plant parts (pseudostem and corm) of two field grown enset clones (Ameratye and Yesherakinkye) was investigated. Proximate analysis showed that extended drought significantly (P £0.05) reduced crude protein, ash content, potassium and phosphorus contents of enset pseudostem and corm of the two clones. On the other hand, crude fibber content and calcium levels were significantly higher in droughted groups than irrigated ones. There were no significant treatment effects on crude fat content and /or magnesium levels. Moreover, drought resulted in a significant increase in the level of soluble sugars and a decline in starch content of plant parts in both clones. Droughted plants accumulated 2–4 fold more soluble sugars than irrigated groups while the latter group gained 14–23% more starch. There was no significant difference between the two clones for the parameters considered. Low nutrient content of droughted plants could be the result of reduced nutrient uptake and assimilation caused by low soil water content and limited energy source (carbon skeleton). The observed increase in soluble sugars could be an indication of osmotic adjustment mechanisms in droughted enset plants. On the other hand, the decline in starch content could be due to reduced carbon assimilation and/or starch degradation

COMPARISON OF THE FROST RESISTANCE OF BARLEY (HORDEUM VULGARE L.) LANDRACES OF UPLAND ETHIOPIA USING ELECTROLYTE-LEAKAGE AND CHLOROPHYLL FLUORESCENCE

Barley is the most important crop in the highlands of Ethiopia at altitudes above 2600 m, where its productivity is limited by cold stress. We studied 25 Ethiopian barley landraces in order to identify cold tolerant types and to describe characteristics and acclimation potentials of these landraces to cold stress. Barley plants were grown from seeds in a temperature-controlled greenhouse (20/15°C) for six weeks prior to investigation. Membrane leakage, assayed by electric conductivity, was investigated before and after the plants had been subjected to freeze-thaw cycles at different sub-freezing temperatures down to -10°C. The critical temperature (CT50), at which the frost-induced damage was 50% of the maximal injury, ranged for most landraces between -5.6 and  -8.6°C. Maximum difference in sensitivity to frost among the various races was observed at -5.0°C. Neither the altitude of the habitat, from where the seeds had been collected, nor the maturation time of the landraces were correlated with the degree of frost tolerance of the landraces. The influence of the growth conditions on the capability of frost hardening of cold-tolerant and sensitive landraces was investigated using chlorophyll a fluorescence. Barley seedlings were grown under three different regimes: In a temperature controlled greenhouse (20/15°C, day/night), under simulated tropical alpine conditions (tropical-alpine greenhouse, 16/0°C, 12 h light period), and in a phytotrone at constant 2°C day and night. Effective quantum yield of photosynthesis was measured at several temperatures in the course of freeze-thaw cycles (+20 to -10 to +20°C). Whereas growth and the effective photosynthetic quantum yield of the plants in the phytotrone were low, cold hardening was effective as shown by the recovery of the photosynthetic quantum yield upon re-warming of the frozen plants. Effective quantum yield of the plants grown in the tropical alpine greenhouse was as high as with the control plants, but only 2 of 6 investigated landraces showed immediate recovery of the photosynthetic quantum yield after freezing. Landraces which showed the highest cold tolerance were found to acclimatize best

Genetic Variation, Genotype by Environment Interactions and Grain Yield Stability Analysis in Finger Millet Accessions Resulted in the Release of an Improved Variety

The use of multiple data sets, such as morphological, biochemical and molecular in combination with appropriate statistical analysis tools are essential in  identifying inter and intra-species variation to develop improved cultivars. To this end, a total of 150 finger millet accessions, of which 105 were collected  from Ethiopia, 39 introduced from eastern and south eastern Africa and six commercially released Ethiopian varieties were evaluated at Arsi Negele and  Gute research sites in 2011. Among those, 138 accessions were genotyped using 20 Simple Sequence Repeat (SSR) markers at International Crop  Research Institute for Semi-Arid Tropics (ICRISAT), Nairobi, in 2012. Highly significant (P ≤ 0.01) variations were observed among the 150 accessions for  grain yield and other agronomic traits. A total of 199 alleles were recorded with an average of 9.95 alleles per microsatellite locus and polymorphism  information content (PIC) of 0.57 was observed. Hierarchical clustering based on major phenotypic traits revealed that the majority of accessions from  the same region and adjoining geographical region shared strong phenotypic similarity and thus grouped together. Weighted Neighbor Joining based on  SSR data grouped the test accessions into three major clusters that were not entirely based on geographical origin. Based on the magnitude of  phenotypic and genotypic diversity and blast disease tolerance, 30 finger millet genotypes were selected for further evaluation at multi-location (Arsi  Negele, Assosa, Bako and Gute) in the 2012 and 2013. Additive Main effect and Multiplicative Interaction (AMMI), and Genotype and Genotype by  Environment Interaction (GGI) biplot analysis revealed that Acc. 203544 was found to be the most stable and highest yielding (3.16 ton ha-1), with yield  advantage of 13.7% over the best standard check, Gute (2.78 ton ha-1). Thus, this accession was officially released with the name “Addis-01” and  recommended for production in the test environments and similar agro-ecologies in the country

Affordable and robust phenotyping framework to analyse root system architecture of soil-grown plants

The phenotypic analysis of root system growth is important to inform efforts to enhance plant resource acquisition from soils. However, root phenotyping still remains challenging due to soil opacity, requiring systems that facilitate root system visibility and image acquisition. Previously reported systems require costly or bespoke materials not available in most countries, where breeders need tools to select varieties best adapted to local soils and field conditions. Here, we report an affordable soil‐based growth (rhizobox) and imaging system to phenotype root development in greenhouses or shelters. All components of the system are made from locally available commodity components, facilitating the adoption of this affordable technology in low‐income countries. The rhizobox is large enough (~6000 cm2 visible soil) to not restrict vertical root system growth for most if not all of the life cycle, yet light enough (∼21 kg when filled with soil) for routine handling. Support structures and an imaging station, with five cameras covering the whole soil surface, complement the rhizoboxes. Images are acquired via the Phenotiki sensor interface, collected, stitched and analysed. Root system architecture (RSA) parameters are quantified without intervention. RSA of a dicot (chickpea, Cicer arietinum L.) and a monocot (barley, Hordeum vulgare L.) species, which exhibit contrasting root systems, were analysed. Insights into root system dynamics during vegetative and reproductive stages of the chickpea lifecycle were obtained. This affordable system is relevant for efforts in Ethiopia and other low‐ and middle‐income countries to sustainably enhance crop yields and climate resilience

In vitro antibacterial activity of some antibiotics against Xanthomonas campestris pv. musacearum: Ensete ventricosum (Welw.) Cheesman Pathogen

Enset bacterial wilt caused by Xanthomonas campestris pv. musacearum (Xcm) is a destructive disease of Ensete ventricosum (Welw.) Cheesman) in south and southwestern Ethiopia. There is no known Bactericide against Xcm and the disease is systemic in nature, making the management very difficult. The objective of the study was to evaluate the antibacterial activity of amoxicillin, cephalexin, chloramphenicol, streptomycin sulphate and tetracycline in vitro against Xmc. The pathogen was isolated from infected Enset pseudostem and its identity was confirmed by pathogenicity test. The antibacterial activity of antibiotics was evaluated using disc diffusion method. Minimum inhibitory concentration (MIC) was determined using agar dilution method. Sub-culturing the contents of MIC onto growth medium was used to know the Minimum bactericidal concentration (MBC). All antibiotics showed antibacterial activity against Xcm, but with varied potency. Significant differences were recorded between test concentrations and antibiotics. Streptomycin sulphate was found to be the most effective antibiotic in inhibiting the growth of Xcm followed by amoxicillin and tetracycline. Moreover, the MIC and MBC values of antibiotics indicate the potential to use in Enset bacterial wilt control. Accordingly, tetracycline showed the lowest MIC (0.02 mg/mL) and MBC (0.049 mg/mL) values against Xcm as compared to others. Thus, it could be used in the management of Enset bacterial wilt. However, further studies need to be conducted on the effectiveness and method of application of tetracycline under field condition

Tending for cattle: traditional fire management in Ethiopian montane heathlands

Fire has long been a principal tool for manipulating ecosystems, notably for pastoralist cultures, but in modern times, fire use has often been a source of conflicts with state bureaucracies. Despite this, traditional fire management practices have rarely been examined from a perspective of fire behavior and fire effects, which hampers dialogue on management options. In order to analyze the rationale for fire use, its practical handling, and ecological effects in high-elevation ericaceous heathlands in Ethiopia, we used three different information sources: interviews with pastoralists, field observations of fires, and analysis of vegetation age structure at the landscape level. The interviews revealed three primary reasons for burning: increasing the grazing value, controlling a toxic caterpillar, and reducing predator attacks. Informants were well aware of critical factors governing fire behavior, such as slope, wind, vertical and horizontal fuel structure, and fuel moisture. Recent burns (1–4 years since fire) were used as firebreaks to control the size of individual burns, which resulted in a mosaic of vegetation of different ages. The age structure indicated an average fire return interval of ~10 years. At these elevations (> 3500 m), the dry period is unreliable, with occasional rains. Of all observed fires, 83% were ignited during very high Fire Weather Index levels, reached during only 11% of all days of the year. Burning is illegal, but if this ban was respected, our data suggest that the Erica shrubs would grow out of reach of cattle within a few years only, creating a dense and continuous canopy. This would also create a risk of large high-intensity wildfires since the landscape is virtually devoid of natural fuel breaks. Under the present management regime, this heathland ecosystem should be quite resilient to degradation by fire due to a relatively slow fuel buildup (limiting fire intervals) and an effective regrowth of Erica shoots. Nevertheless, if burning is done during severe drought, there may be a risk of smoldering fires killing the lignotubers. Given the intimate knowledge of fire behavior and fire effects among these pastoralists, it should be possible to develop a fire management plan that can sustain the present land use and ecosystem, and be sanctioned by both authorities and the local community

In vitro evaluation of the antibacterial activity of some medicinal plant extracts against Xanthomonas campestris pv. musacearum

Enset bacterial wilt caused by Xanthomonas campestris pv. musacearum (Xcm) is a destructive disease of Ensete ventricosum (Welw.) Cheesman) in Ethiopia. The antibacterial activities of methanol leaf extracts of Achyranthes aspera, Agarista salicifolia, Datura stramonium, Melia azedarach, Pycnostachys abyssinica and Vernonia amygdalina were evaluated in vitro against Xcm. Fresh leaves were collected, dried under shade and ground to fine powder. Extraction was carried out using maceration method. The antibacterial activity of extracts was evaluated by disc diffusion method. Total phenolics content was estimated using Folin Ciocalteau method. The result revealed that higher percent extract yield was obtained from A. salicifolia followed by P. abyssinica. Extracts of all species showed antibacterial activity except M. azedarach. Significant differences in inhibition zone diameter were recorded between species and among test concentrations. The widest inhibition zone was recorded by A. salicifolia followed by P. abyssinica. Unlike others, extract of A. salicifolia had abundant amount of alkaloids, flavonoids, phenols, terpenoids, saponnins, tannins and cardiac glycosides. The remaining species lacked one or more of these metabolites and the existing ones occurred either in small or moderate amount. Moreover, the extract of A. salicifolia was found to have the highest total phenolics content and this was positively correlated with inhibition zone diameter at all test concentrations suggesting its potential antibacterial activity. This shows that the extract of A. salicifolia has the potential for further bioformulation and commercialization as biocide with broad spectrum activity. However, further research should be conducted to identify the active compounds responsible for such antibacterial activity.Keywords: Ensete ventricosum; Agarista salicifolia, Pycnostachys abyssinica, Inhibition zone;Total phenolic

Trends and gaps in Enset (Ensete ventricosum (Welw.) Cheesman research

Enset is a multipurpose crop that supports the livelihood of 20 million people. Enset starch is also used for paper, textile, adhesive industries and pharmaceuticals in tablet formulation as a binder and disintegrant. However research and extension on the crop was given attention recently. It was only in the 1970s that enset research, begun focusing on enset clone collection, evaluation for food, fiber, and maintenance of germplasm. This was followed by agronomic studies on the effect of traditional management methods such as transplanting, spacing and leaf pruning on dry matter production, food production and harvest indices. Some ecophysiological studies revealed that drought tolerance in enset was attributed to osmotic adjustment and improved water extraction through altered biomass partitioning. Currently, serious attention is given to the threat of enset bacterial wilt to enset cultivation. Consequently, research activities on the use of medicinal plant extracts and other bio-control agents and methods against bacterial wilt pathogens, and selection of disease resistance varieties have been initiated through coordinated multidisciplinary research to alleviate the problem of enset bacterial wilt. Despite the relatively better research attention given to enset in the past two decades, as compared to the previous ones, there are still several research gaps that need to be addressed. It is recommended that establishing a national database on enset research with periodic bibliographic publication; creating a clone collection centre; developing a prioritized enset research agenda and creating a National Enset Research Institute is of paramount importance. This will ensure the sustainable production of the crop for food security, income generation, agroindustry development and environment sustainability.Keywords/phrases: Agronomy, Ecophysiology, Enset bacterial wilt, Enset diversity, Osmotic adjustmen