Advances in Crop Science and Technology
Open Access

Onion varieties; Performance evaluation; Bulb yield

Onion (Allium Cepa L.) belongs to the family Liliaceae, an important group of crops worldwide. Onions exhibit particular diversity in the eastern Mediterranean countries, through Turkmenistan, Tajikistan to Pakistan and India, which are the most important sources of genetic diversity and believed to be center of origin. Onion is one of the oldest bulb vegetables in continuous cultivation dating back to at least 4000 BC. Onions are grown mainly as food materials however; they have medicinal properties and has been used for the treatment of various ailments such as skin diseases, ear pain, heart attack and strokes. The bulbs are boiled and used in soups and stews, fried or eaten raw in salads. Although its main role in cooking is to provide flavor, onion is a significant source of vitamin C and potassium, contains about 60 calories in a medium-sized bulb, and has very low sodium content. It also contains the vitamins thiamine, riboflavin and niacin and is used for its medicinal value especially in the case of heart problems. They also contain a phytochemical called quercetin, which is effective in reducing the risk of cardiovascular disease, an anticancer, and has promise to be an antioxidant [1].

A cultivar crop performs differently under different agro-climatic conditions and various cultivars of the same species grown even in the same environment give different yields as the performance of a cultivar mainly depends on the interaction of genetic makeup and environment. The optimum altitude range for onion production is between 500 and 2200 m.a.s.l and the temperature ranged between 12.4ºC to 31.3ºC [2].

In Ethiopia, it has an economically important place among other vegetable crops due to ease of production, high profitability per unit area and increase in small-scale irrigation schemes, the area under production of the onion is increasing from time to time. Onion was grown on about 1,681.51 ha in SNNP Region from which about 17,367.42 tons onion yield was produced with the average zonal yields 10.3t ha-1 (CSA, 2017). However, this tuber yield is far less than the attainable yield (50-60 t ha-1) under good management conditions (MOANR, 2017).

There are a number of production problems which makes the farmers not to produce onion in advanced manner. Among that production problem the low yield because of lack of improved varieties, non-optimal agronomic practices, unavailability and high cost of seed, the prevalence of diseases and insect pests. Moreover, improved onion varieties are limited in South Omo Zone and farmer/agro-pastorals using their own local cultivars, which result they produced low yield per hectare. Therefore, to alleviate this problem, the experiment was conducted with the objective of identify superior onion variety/ies in terms bulb yield and desirable agronomic traits for study area.

Description of the Study Area

The experiment was conducted during 2018 cropping season at Omorate (lobet keberle) and 2019 at Weyito (Enchete kebele). Omorate which located South Omo Zone in Southern Nations, Nationalities and People’s Regional State. Omorate which is located South Omo Zone in Southern Nations, Nationalities and People’s Regional State. It is situated between 4°37′-4°58 Regular North latitude and 35°56 Regular-36°20 Regular East longitude with altitude of 365 above sea level [3]. The rainfall distribution of the area is bimodal, with a primary rainy season between March to May and secondary small rain between Septembers to December. The monthly average minimum and maximum temperature is 24.4°C-37.8°C, respectively. Weyito also located South Omo Zone in Southern Nations, Nationalities and People’s Regional State. It is situated between 5°01’-5°73’ North latitude and 36°38’ - 37°07’ East longitude with altitude of 588 meter above sea level. The rainfall distribution of the area is bimodal with main rainy season extends from January to May and the second cropping season, from July to October. It receives annual average rainfall of 876.3 mm and the monthly average minimum and maximum temperatures of 18.2 and 37.3°C, respectively. All the metrological data a given above for the two location are long term averages.

Experimental treatments and design

Five improved onion varieties namely: Nafis, DZSHT- 91-2B, DZSHT-157-1B, Adama Red, Nasick Red and one Local check were used for current study. These varieties were arranged in randomized complete block design (RCBD) with three replications [4].

Experimental procedures

Onion varieties were planted at recommended seeding rate of 4kg/ ha. A randomized complete block design with three replication was used. Seeds were sown on seed bed and four leaves stage seedlings were transplanted in plot of 3m x3m. Row to row and plant to plant spacing was 40cm and 20cm respectively. As per recommended fertilizer rate of 100kg/ha of NPS was applied at transplanting and half of Urea which is 75kg/ha was applied at transplanting and the remaining half of urea (75kg/ha) was applied six weeks or 45 days after transplanting. The irrigation water was applied by using furrow irrigation method from 5 up to 10 days interval at according weather condition. All the recommended cultural practices in growing period of onion were applied.

Collected data

Plant height was measured from the ground level up to the tip of the longest leaf using a measuring tape. It was measured using five randomly selected plants from the two central rows of each plot at physiological maturity of the crop and the average values competed. Number of leaves per plant was counted from five randomly taken plants from the middle rows at physiological maturity and the average was computed for each plant. Bulb diameter was measured at right angles to longitudinal axis at the widest circumstance of the bulb of five randomly taken plants in each plot by using veneer caliper (model 141). The harvested bulb of all varieties were left to dry in shade for four days then the leaves were removed to get the dry bulbs of onion. Thereafter, harvested onions were weighed using an electronic balance then expressed as kg per plot and converted into t ha-1 [5].

The various collected data were subjected to analysis of variance appropriate to randomized complete block design (RCBD) using SAS software version 9.2 (SAS, 2008) with a generalized linear model (GLM) procedure. Means were separated using least significant differences (LSD) test at 5% level of significance [6].

Plant height (cm) The mean result of onion varieties revealed non-significant (P<0.05) difference among tested varieties on plant height at two locations (Omorate and Weyito) presented. This result was in agreement to the findings of Misgana and Awoke who reported that, non-significant difference among onion varieties on plant height [7].

Number of leaves per plant

At Omorate, the analysis of variance revealed non-significant (P<0.05) difference among tested varieties on number of leaves per plant. However at Weyito, there was significant (P<0.05) difference among tested varieties on number of leaves per plantThe highest number of leaves per plant (21.7) was measured from variety DZSHT- 91-2B followed Nafis (17.3), while the lowest number of leaves per plant (11.6) was recorded from variety DZSHT-157-1B. The possible reason for significant and non-significant difference among varieties on plant height at Omorate and Weyito location might be due to the fact that environmental conditions and years. This result was in agreement with Demisie who obtained variation among onion varieties for number of leaves per plant. Similarly, Bindu who studied on onion found that the significantly differ on number of leaf per plants [8].

Bulb diameter

Bulb diameter was highly significantly affected (P˂0.01) by variety at both locations. Variety DZSHT-91-2B gave the highest (5.7cm) bulb diameter at Omorate location which, is did not significantly differ from Nafis, Nasik- Red and Adama Red varieties, while the lowest (4.1) bulb diameter was gained from local variety in the same location. Similarly, significantly the highest (6.3cm) bulb diameter was recorded from Variety DZSHT-91-2B at Weyito which is did not significantly differ from Nafis, Nasik Red, Adama Red and DZSHT-57-1B varieties; whereas, the lowest bulb diameter (4.6) were recorded from variety Local. This is due to the reality that varieties can have different genetic makeup that makes them different. Similarly Yemane reported variation among onion varieties for bulb length [9].

Average bulb yield

The average fresh bulb of onion was influenced (P˂0.01) by variety at both locations. Variety DZ-SHT- 91-2B had significantly highest bulb weight (27.2 t ha-1) followed by variety Nafis (22.8 t ha-1), while the lowest (15.2 t ha-1) bulb yield was recorded from local variety at Weyito location. Similarly, significantly the highest (23.7cm) bulb yield was recorded from Variety DZ-SHT- 91-2B at Omorate; whereas, the lowest bulb diameter (12.1) was recorded from variety local which was not significantly differ from DZSHT-57-1B variety. Generally, DZSHT-91-2B variety produced more tuber yield and was superior to the others varieties at Omorate and Weyito location. The presence of significant differences among the tested varieties might be due to the existence dissimilarity in genetic composition among them, for that fact characters may be differ in their genetic properties. Besides, environmental or years influences might be the possible causes of their significant differences or both. The present study was in agreement with findings of Demisie and Tolessa who obtained significantly difference on bulb yield of onion varieties. Similarly, Neim who studied on onion found that significantly difference among they used test varieties [10].

Conclusion and Recommendation

Onion is an important vegetable in Ethiopia. However, the yield of this vegetable is limited mainly due to shortage of improved varieties suited to specific area. This field experiment was conducted to evaluate onion varieties for bulb production at Omorate and Weyito in South Omo Zone, Southern Ethiopia. The experiment contains six varieties namely: Nafis, DZSHT-91-2B, DZSHT-157-1B, Adama Red, Nasick Red and Local. The experiment was conducted using randomized complete block design with three replications. Data were collected on Number of leafs per plant, plant height, bulb diameter and bulb yield and subjected to analysis of variance using SAS software program. The result of this study revealed that, there was significant difference among varieties in bulb yield at both locations viz, Omorate and Weyito.

From the results of this study the highest average bulb yield was produced from DZSHT- 91-2B and Naifs varieties, respectively at both locations viz, Omorate and Weyito. It can be concluded that variety DZSHT- 91-2B is the superior onion variety followed by Nafis which can improve onion production in low land area of South Omo Zone and its vicinity. Therefore, it can be promoted to PED at around tested areas.

1. Yusof HM (2019) Microbial Synthesis Of Zinc Oxide Nanoparticles And Their Potential Application As An Antimicrobial Agent And A Feed Supplement In Animal Industry: A Review. J Anim Sci Biotechnol 10:1-22.

Crossref, Google Scholar, Indexed at

2. Timilsina H (2021) Current Trends of Food Analysis, Safety, and Packaging.       Int J Food Sci 23: 32-34.

Crossref, Google Scholar, Indexed at

3. Zhao Y (2021) Novel Strategies for Degradation Of Aflatoxins In Food And Feed: A Review. Int Food Res J 140: 32-34.

Crossref, Google Scholar, Indexed at

4. Banaszak M (2021) Wheat Litter and Feed With Aluminosilicates For Improved Growth And Meat Quality In Broiler Chickens. Int Food Res 9:12-13.

Crossref, Google Scholar, Indexed at

5. Liang JF (2021) A Review of Detection of Antibiotic Residues in Food by Surface-Enhanced Raman Spectroscopy. Bioinorg Chem Appl. 8:27-32.

Crossref, Google Scholar, Indexed at

6. Zhang E (2021) Glycyrrhiza Polysaccharides Can Improve and Prolong the Response of Chickens to the Newcastle Disease Vaccine. Poult Sci 101:34-38.

Crossref, Google Scholar, Indexed at

7. Shang X (2021) Effects Of Zinc Glycinate On Growth Performance, Serum Biochemical Indexes, And Intestinal Morphology Of Yellow Feather Broilers. Biol Trace Elem Res 8:1-9.

Crossref, Google Scholar     

8. Ramaswamy K (2021) Experimental Investigation on the Impacts of Annealing Temperatures On Titanium Dioxide Nanoparticles Structure, Size And Optical Properties Synthesized Through Sol-Gel Methods. Mater Today Proc 45:5752-5758.

Crossref, Google Scholar, Indexed at

9. Shah GA (2021) Toxicity of Nio Nanoparticles to Soil Nutrient Availability And Herbage N Uptake From Poultry Manure. Scien Repor 11:11540.

Crossref, Google Scholar      

10. Banaszak M (2021) Aluminosilicates At Different Levels In Rye Litter And Feed Affect The Growth And Meat Quality Of Broiler Chickens. Vet Res Commun  46:37-47.

Crossref, Google Scholar, Indexed at