Papers by Alemu D E S S A Derebe
Taro production is mainly affected by agroecology, planting time and planting density. To this ef... more Taro production is mainly affected by agroecology, planting time and planting density. To this effect, a field study was conducted to determine influences of planting density and planting dates on growth, radiation interception and yields of taro (Colocasia esculenyta (L.)). The experiment was conducted using four levels of planting density (15037, 19607, 26666 and 38461 plants ha-1) and four planting dates from mid-February to mid-April at 21 days interval at Areka and Hawassa locations. SAS statistical software package was used for the analysis of the data derived from the experiment. From the analysis, interaction of location by planting dates significantly (p<0.01) influenced date of emergence, stand count and plant height. While, leaf area, leaf area index (LAI) and plant height, were significantly influenced due to location by planting density interactions. However, dry matter production (DMP) was influenced by planting density only. Cumulative interception photosynthetically active radiation (CIPAR), corm weight, cormels number, marketable yield and total yield per plant were significantly (p≤0.05) influenced both by plant density and planting dates. Maximum total and marketable yield were obtained from 15037 plant ha-1 at late and early March planting dates. Plant density and planting dates are therefore important agronomic management practices to improve the productivity of taro through enhancing the capacity of plant for light interception, growth and dry matter production.
Cogent Food & Agriculture, 2023
Abstract: Agricultural fields prone to waterlogging condition induce physiological
stress on frui... more Abstract: Agricultural fields prone to waterlogging condition induce physiological
stress on fruit trees as it affects root respiration and nutrient uptake. However, the
information on the growth performance of avocado under waterlogging condition is
limited, particularly in terms of morphological and physiological performances.
Therefore, this study was designed to evaluate the performance of avocado rootstocks
under different waterlogging levels under shade condition. The experiment
was conducted using a complete randomized design with factorial arrangement
using Ettinger variety as scion that was grafted on Guatemalan and Mexican rootstock
races at three waterlogging levels (50%, 75% and 100%) in three replications.
The result showed that morphological growth of avocado grafted on Guatemalan
race outscored in number of buds, shoot growth, rootstock elongation and scion
shoot tip growth compared to the one grafted on Mexican race. Similarly, photosynthesis,
transpiration and stomata conductance were significantly affected by the
Enset is not just a food crop, but is a multipurpose crop of which every part of the plant (excep... more Enset is not just a food crop, but is a multipurpose crop of which every part of the plant (except the root) is utilized, for food and several non-food applications. Conventionally enset is propagated by vegetative means from underground rhizome/corm. In vitro enset multiplied from any part of plant by the use plant growth regulating hormones. However, hormone application is not commonly utilized on in situ enset propagation. Therefore, this study was designed to study the impact of hormone concentration on corm size and different accession on in situ sucker multiplication. An experiment was conducted in factorial arrangement using RCBD with sixteen treatments each replicated three times. The treatment consisted of four NAA+BAP mg/l combined concentration (0.75 NAA+2.25 BAP, 1.5 NAA+4.5 BAP, 3.0 NAA+9.0 BAP and 0 NAA+0 BAP mg/l) two clones ("kaati ziinik" and "ziinik buukuma") and two corm sizes (whole corm and halved corm). Data related to sucker multiplication and sucker growth parameters collected during the experiment period. Clone kaati ziinik couple with whole corm size gave the maximum sucker than halved corm. However, clone "ziinik buukuma" produced vigorous and larger number of sucker from halved corms than using whole corm. The interaction of hormone concentration, clone and corm size was significantly influenced number of sucker, number of root; leaf area index and sucker dry weight. The maximum number of sucker and leaf area index were recorded from whole corm of clone KZ treated with NAA/2.25 BAP mg/l hormone concentrations. In general, it was observed that the highest number of root was recorded by halved and whole corm of clone KZ treated with 1.5 NAA + 4.5 BAP mg/l and 3.0 NAA + 9.0 BAP mg/l combined concentration, respectively. The highest developed dry weight of sucker was scored from whole corm of clone KZ treated with 1.5 NAA + 4.5 BAP mg/l combined concentration. The finding of this study provides an evidence for the application of plant growth regulating hormones on in situ multiplication of Enset from corm. In general, to use 1.5 NAA + 4.5BAP mg/l combined concentration on clone ZB with halved corm is recommended. It was observed comparatively the high number of emerged sucker, leaf area index number of root and minimizes cost of corm.
Taro production is mainly affected by agroecology, planting time and planting density. To this ef... more Taro production is mainly affected by agroecology, planting time and planting density. To this effect, a field study was conducted to determine influences of planting density and planting dates on growth, radiation interception and yields of taro (Colocasia esculenyta (L.)). The experiment was conducted using four levels of planting density (15037, 19607, 26666 and 38461 plants ha-1) and four planting dates from mid-February to mid-April at 21 days interval at Areka and Hawassa locations. SAS statistical software package was used for the analysis of the data derived from the experiment. From the analysis, interaction of location by planting dates significantly (p<0.01) influenced date of emergence, stand count and plant height. While, leaf area, leaf area index (LAI) and plant height, were significantly influenced due to location by planting density interactions. However, dry matter production (DMP) was influenced by planting density only. Cumulative interception photosynthetically active radiation (CIPAR), corm weight, cormels number, marketable yield and total yield per plant were significantly (p≤0.05) influenced both by plant density and planting dates. Maximum total and marketable yield were obtained from 15037 plant ha-1 at late and early March planting dates. Plant density and planting dates are therefore important agronomic management practices to improve the productivity of taro through enhancing the capacity of plant for light interception, growth and dry matter production.
Salt stress is the most important environmental stress that adversely affects avocado morpho-phys... more Salt stress is the most important environmental stress that adversely affects avocado morpho-physiological performance. Therefore, this study has been conducted to evaluate the response of avocado seedlings to different salinity levels. The experiment was laid out in a Randomized Complete Design (RCD) with four salt concentration levels (0, 1.3 dS/m, 2.6 dS/m, and 3.9 dS/m) on grafted avocado seedlings, with three replications. The avocado seedlings were raised from Ettinger avocado scion grafted on Guatemalan race rootstock. The results indicate that most of the morphological growth parameters, such as rootstock diameter, sucker development, and root length, were significantly (p<0.01) affected by salt stress level. While tap root diameter and lateral root length were not significantly (p>0.05) affected by salt treatment. Except for the number of suckers developed on the rootstock, rootstock and scion diameter significantly decreased as salt concentrations increased from 0 to 3.9 dS/m. Similarly, significant (p<0.01) variations were also observed in leaf length, bud number, leaf fresh weight and dry weight, leaf area, shoot height, taproot length, and lateral root length. These parameters were also significantly decreased with the increase in salt concentrations. Likewise, photosynthesis, transpiration, stomatal conductance, and instantaneous water use efficiency were significantly affected by salt concentration, where relatively maximum scores were obtained at 0 and 1.3 dS/m. In general, salt concentration at 0 and 1.3 dS/m EC favors most of the growth and physiological performance of avocado seedlings compared to 2.6 and 3.9 dS/m. Thus, the study revealed that for vigorous growth of avocado seedlings at an early stage, the quality of irrigation water needs considerable attention to ensure robust avocado seedling growth.
Ethiop. J. Appl. Sci. Technol., 2023
Planting density is important agronomic management tool for potatoes as it determines light inter... more Planting density is important agronomic management tool for potatoes as it determines light interception, growth, yield and yield components of the crop. However, the information at spasfic location is limited. Thus, the experiment was conducted to determine the optimum plating density for potato varieties and its impact on growth, light interception, yield and yield components. A field experiment was conducted at Bore in the southeastern Ethiopia during the 2021 cropping season. The experiment consists of four levels of planting densities (66667, 44444, 33333 and 26667 plant ha-1) and four potato varieties: three improved (Jalanie, Gudenie, Belete and one local (Gujicha) that were laid out in a randomized complete block design (RCBD) in factorial arrangements with three replications. The result indicated that the main effects of variety and planting density significantly (p < 0.001) influenced days to 50% flowering, 90% maturity date, plant height, number of stems per hill, leaf area index (LAI) at 45, 60 and 75, Cumulative Interception Photosynthetic Active Radiation (CIPAR) and total dry matter production. However, tuber yield, tuber weight, average tuber number per hill, marketable yield and total tuber yield were significantly affected by the interaction effects. The overall result indicated that CIPAR increased with increasing planting density, though a maximum marketable tuber yield of 44.92 t ha-1 was recorded at 444444 plant ha-1 from Gudenie variety. However, the CIPAR was not fit with the maximum marketable and total yield of tuber; this indicates other plant and environmental factors might also significant for plants to express their yielding potential.
Scientia Horticulturae, Oct 1, 2019
Greener Journal of Agronomy, Forestry and Horticulture, 2014
Scientia Horticulturae, 2019
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Papers by Alemu D E S S A Derebe
stress on fruit trees as it affects root respiration and nutrient uptake. However, the
information on the growth performance of avocado under waterlogging condition is
limited, particularly in terms of morphological and physiological performances.
Therefore, this study was designed to evaluate the performance of avocado rootstocks
under different waterlogging levels under shade condition. The experiment
was conducted using a complete randomized design with factorial arrangement
using Ettinger variety as scion that was grafted on Guatemalan and Mexican rootstock
races at three waterlogging levels (50%, 75% and 100%) in three replications.
The result showed that morphological growth of avocado grafted on Guatemalan
race outscored in number of buds, shoot growth, rootstock elongation and scion
shoot tip growth compared to the one grafted on Mexican race. Similarly, photosynthesis,
transpiration and stomata conductance were significantly affected by the
stress on fruit trees as it affects root respiration and nutrient uptake. However, the
information on the growth performance of avocado under waterlogging condition is
limited, particularly in terms of morphological and physiological performances.
Therefore, this study was designed to evaluate the performance of avocado rootstocks
under different waterlogging levels under shade condition. The experiment
was conducted using a complete randomized design with factorial arrangement
using Ettinger variety as scion that was grafted on Guatemalan and Mexican rootstock
races at three waterlogging levels (50%, 75% and 100%) in three replications.
The result showed that morphological growth of avocado grafted on Guatemalan
race outscored in number of buds, shoot growth, rootstock elongation and scion
shoot tip growth compared to the one grafted on Mexican race. Similarly, photosynthesis,
transpiration and stomata conductance were significantly affected by the