Horticultural Science

Permanent URI for this collectionhttps://etd.hu.edu.et/handle/123456789/41

Browse

Filters

2024 - 20252

Settings

Start date: 2020Subject: search.filters.subject.Nitrogen

Search Results

Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    GROWTH AND BULB YIELD RESPONSE OF ONION (Allium cepa L.) VARIETIES TO VARYING LEVELS OF NITROGEN AND VERMICOMPOST IN BIISHAAN GURACHAA, OROMIA, ETHIOPIA
    (Hawassa University College of Agriculture, 2025) BADEGE AYELE
    Onion is a vital horticultural crop in Ethiopia, supporting both rural livelihoods and urban food systems. However, its productivity remains low due to poor nutrient management, declining soil fertility, and continued reliance on unimproved varieties. Excessive nitrogen use often results in delayed maturity and reduced bulb quality, while organic inputs like vermicompost remain underutilized. This study was conducted to evaluate the combined effects of nitrogen and vermicompost on the growth, yield, quality, and economic performance of improved onion varieties under highland conditions. A field experiment was carried out during the off-season at Shallo Farm, using a randomized complete block design (RCBD) with three replications. Treatments were arranged in a 3 × 4 × 3 factorial combinations comprising three onion varieties (Rio Bravo f1, Nafis, and SV Runagrana f1), four nitrogen rates (0, 75, 150, and 225 kg N ha⁻¹), and three vermicompost levels (0, 5, and 7 t ha⁻¹), giving 36 treatment combinations. Data were collected on phenology, growth, yield, and bulb quality parameters, and subjected to both agronomic and economic analyses. The three-way interaction among variety, nitrogen, and vermicompost significantly (P < 0.01) influenced most growth, yield, and quality traits. SV Runagrana f1 exhibited the best performance, producing the highest total bulb yield (57.48 t ha⁻¹) and marketable yield (51.13 t ha⁻¹) at 225 kg N ha⁻¹ combined with 7 t ha⁻¹ vermicompost. Excessive fertilization (>225 kg N + 7 t VC ha⁻¹) increased unmarketable yield, delayed maturity, and lowered bulb quality. Economic analysis further revealed that SV Runagrana f1 at 225 kg N + 7 t VC ha⁻¹ provided the highest net field benefit (4,471,000 Birr ha⁻¹), benefit–cost ratio (35.1%), and marginal rate of return (15,000 %), indicating strong profitability despite higher input costs. In contrast, moderate fertilization (75 kg N + 5 t VC ha⁻¹) offered a favorable trade-off between yield stability, quality, and input efficiency, making it a more sustainable option for smallholder farmers. Therefore, the study demonstrated that onion yield, quality, and economic returns are highly dependent on the interaction between genotype and nutrient management.Further studies should investigate long-term soil fertility effects and validate the economic sustainability of these practices across diverse agro- ecological zones.
  • No Thumbnail Available
    Item
    EFFECT OF NPS AND UREA FERTILIZER RATE ON YIELD AND YIELD COMPONENT OF HEAD CABBAGE (Brassica oleracea L.) AT KOFALE DISTRICT, OROMIA REGIONAL STATE, ETHIOPIA
    (Hawassa University College of Agriculture, 2024) MULUWERK ADDISU
    Cabbage is one of the most popular and widely grown vegetable crops in the world. Among the factors responsible for low yields in cabbage, unbalanced use of N and NPS fertilizer was considered the major problem causing a high reduction in the potential yield of cabbage. Hence, a field experiment was conducted in 2023 main cropping season to investigate the effect of N and NPS fertilizer on growth, yield, and yield components of cabbage in Kofale district. The experiment consisted of a factorial combination of three rates of NPS (0, 100, and 200 kg ha -1 ) and four rates of nitrogen (0, 100, 200, and 300 kg ha-1). The interaction effects of N and NPS fertilizer were found to have a significant impact on days to 50% head initiation, days to 90% head maturity, plant height, leaf length, leaf width, head length, head width, folded number of leaf head diameter, fresh and dry head weight, and marketable head yield. The highest head dry weight (0.174 kg plant -1 ) and marketable 118.34 t ha -1 ) head yields were obtained by 200 kg ha -1 NPS and 300kg ha -1 N rate of fertilizer, which were significantly on par with 100 kg ha -1 NPS and 300 kg ha -1 N rate of fertilizer that recorded 118.01 t ha -1 marketable head yields of cabbage. Therefore, the use of 200 kg ha -1 NPS and 300 kg ha-1 N can tentatively be recommended for cabbage producers in the study area.