Article InformationSmallholder irrigated vegetable production in the Central Rift Valley region of Ethiopia is instrumental in ensuring the year-round availability of fresh vegetables in the local market in the country. However, a number of problems constrain irrigated vegetable production in the region. Therefore, asurvey was conducted with the objectives of assessing smallholder irrigated vegetable production practices and identifying factors associated with problems of irrigation water management. The survey was conducted in December 2011. A multistage purposive sampling procedure was employed to select sample districts, peasant associations, and sample respondents that grew vegetables using small-scale irrigation. Key informants were interviewed and group discussions were conducted with smallholder vegetable farmers. Data were collected on household irrigation knowledge, experiences, skills, irrigation water sources as well as on irrigation water management practices such as methods, time, depth and frequency of irrigation. Data were also collected on supplemental irrigation practices under rain-fed vegetable production. In addition, household perceptions on the environmental impacts of irrigation, on-farm irrigation water related challenges, and related information were also recorded. About 16.5% of the respondents indicated that their knowledge and skills on irrigation water management practices were mainly drawn from experiences of trial and error.About 38.1% of the respondents indicated that they irrigated their vegetable fields both in the morning and the afternoon whereas 35.1% replied that they irrigated only in the afternoon. A large number of the respondents (89.6%) replied that they determined irrigation intervals based on specific crop needs. About 90.9% of the respondents replied that they applied enough irrigation water up to the point where the water level reached the furrow basin head. The survey result also indicated that 51.7% of the respondents practiced supplemental irrigation when shortage of moisture occurred in the soil during the rainy season as well at the end of the rainy season. One hundred percent of the respondents replied that they faced problems commonly related with the use of irrigation, namely, soil salinity, waterlogging, soil erosion and degradation, sedimentation, and build-up of pests and diseases. In conclusion, the survey results revealed that extension services on irrigation water management were almost non-existent, and the smallholder vegetable farmers managed irrigation water merely by intuition.Therefore, participatory on-farm irrigation research and extension on irrigation water management practices should be formulated to generate appropriate technologies for enhanced and sustainable irrigated vegetable production in the region.

Hot pepper (Capsicum annuum L.) is an irrigated, high value cash crop. Irrigation requirements can be estimated following a FAO crop factor approach, using information on basal crop coefficients (Kcb), crop coefficients (Kc) and duration of crop growth stages. However, this information is lacking for hot pepper cultivars differing in growth habit and length of growing season under South African conditions. Detailed weather, soil and crop data were collected from three field trials conducted in the 2004/05 growing season. A canopy-cover based procedure was used to determine FAO Kcb values and growth periods for different growth stages. A simple soil water balance equation was used to estimate the ETc and Kc values of cultivar Long Slim. In addition, initial and maximum rooting depth and plant heights were determined. A database was generated containing Kcb and Kc values, growing period duration, rooting depth, and crop height for different hot pepper cultivars, from which the seasonal water requirements were determined. The length of different growth stages and the corresponding Kcb values were cultivar and growing condition dependent. The database can be used to estimate Kcb and Kc values for new hot pepper cultivars from canopy characteristics. The Soil Water Balance (SWB) model predicted the soil water deficits to field capacity and fractional canopy cover well, using the FAO crop factor approach.

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Article Information Large areas of farms are covered by variety of vegetable crops in the Central Rift Valley of Ethiopia. With a view to improve current vegetable production fertilizer use efficiency, survey has been conducted through collections of baseline information to describe household fertilizer uses and soil fertility management in vegetable production system using descriptive statistics. Multistage samplings were made to select representative growers in the six districts of East Showa zone. Based on field observations and group discussions, vegetable growers grouped their farm land into four local categories. The survey revealed that tomato growers apply variable rates of urea and DAP fertilizers for tomato cultivation. Survey results indicated that highest 43.61% of onion growers apply 200 kg of DAP fertilizer on their onion field, while 30.85% of growers apply 300 kg DAP per ha, another 39.35% apply, 400 kg and above DAP fertilizer, still 8.5% of onion growers apply 600 kg DAP fertilizer on their onion farm. This survey indicated that fertilizers were not wisely used in the vegetable crops production systems and the applications are in excess rate, which could leads to pollution of the environment from over dose application and from runoff in to the water bodies and leaching in to the ground water with economic loss. Most of the tomato and onion growers use three splits application of UREA and DAP mainly at transplanting, at first and second cultivation for both crops as top-dressing. The survey results indicated that 54.44% of onion growers apply an average of 230.35 kg ha-1 DAP at transplanting, while 46.53% apply an average of 188.29 kg ha-1 DAP at second split application, and finally 17.82% apply an average of 119.44 kg ha-1 DAP at last third split applications. This is the first document come across that vegetable growers in the CRV area apply DAP fertilizer as much as three splits. This indicates that there are no systems of updating of frontline development workers; poor extension services with shallow development workers knowledge made the growers totally depend on their own innovations for vegetable production.

Low soil fertility and climate change-induced low soil moisture are major problems constraining potato (Solanum tuberosum L.) production in the eastern highlands of Ethiopia. Climate events are projected to become more pervasive. Therefore, research was conducted with the objective of analyzing smallholder potato farmers’ adaptation strategies to cope with the issues of low soil fertility and low soil moisture that are exacerbated by climate change. The research involved surveying eight purposively selected peasant associations in four major potato-producing districts in east and west Hararghe zones. The survey employed a multistage sampling procedure. Data were collected from 357 households using a standard questionnaire, focus group discussions, and key informant interviews. The data were analyzed using descriptive statistics, index ranking, and analysis of variance for survey data. The observed climate data for the period of 1988 to 2017 were analyzed. The Mann-Kendall trend test, standard anomaly index, precipitation concentration index, and coefficient of variation were used to analyze the observed climate data. The survey results revealed the farmers, on average, applied 159 kg urea, 165 kg NPS (63 kg P2O5, 31 kg N and 12 kg S), and 1.8 ton of farmyard manure per hectare for producing potatoes. Most smallholder farmers (68.91%) used supplemental irrigation for potato production during the main growing season. The method of irrigation the farmers used was overwhelmingly the furrow method (92.72%). Analyzing the climate data showed that the mean annual temperature increased whereas the mean annual rainfall decreased during the 30-year period. It was concluded that climate change is markedly affecting potato production; in response to this, most of the farmers used supplemental irrigation to cope with moisture stress, all of them applied mineral fertilizers, and some of them additionally applied organic fertilizer to alleviate the problems of soil degradation and nutrient depletion. This implies that soil moisture and nutrient stresses are the major problems constraining potato production against which the farmers need policy and institutional supports to consolidate their coping strategies and build resilience against climate change.