Optimum Determination of NPSB Fertilizer Rates on Bread Wheat (Triticum aestivum L.) Varieties
The field experiment was conducted in Degam district during the main cropping season to investigate the response of bread wheat varieties to NPSB fertilizer rates and identify its economic benefit. A factorial combination of three improved bread wheat varieties (Dandaa, Hidase, and Kakaba) and six fertilizer rates [Control, 50, 100, 150, 200 kg ha-1 NPSB fertilizer each supplemented with 92 kg N ha-1 and 64/20 kg NP ha-1 (Blanket recommendation)] were laid out in randomized complete block design with three replications. The highest NKS (54.9), AGBM (13.8 tons ha-1), SY (9.4 tons ha-1) and GY (4549kg ha-1) were recorded from 200 kg NPSB fertilizer. Among the varieties, the highest NKS (54.3) from Dandaa, TKW (49.3 g), and GY (3351kg ha-1) were recorded from the Hidase variety. Variety Kakaba scored the highest PH (102.5 cm) and PNT (5 per plant) with a combination of 200 kg and 150 kg NPSB fertilizer respectively and reached days to heading and maturity earlier than Dandaa and Hidase. In general, the economic feasibility of the fertilizer over varieties combination indicated that application of 200 kg NPSB ha-1to all varieties Hidase, Dandaa, and Kakaba resulted in maximum marginal rates of return 640.14 %, 604.81%, and 481.47%, with a net benefit of 97993, 88596, and 82996 ETB respectively. However, the application of 200 kg NPSB ha-1 led to the highest MRR for the Hidase variety as compared to all other treatments and with about a total of 9397 ETB net benefit increment. Therefore, the application of 200 kg of NPSB in supplement of 92 kg N ha-1 fertilizer with Hidase variety was the best producing economically profitable with acceptable grain yield.
Wheat is a staple food that provides around 20% of protein and calories consumed worldwide (FAOSTAT, 2015). The demand for wheat is expected to grow by 34 to 60% in 2050 in developing countries (Valin, 2014). The FAO estimates that global commercial production of all types of wheat was 650.9 million metric tons in 2016, harvested from 217.0 million hectares; it is grown on around 4% of the planets agricultural land (FAO, 2017; Sharmin et al., 2021).
Ethiopia is one of the largest wheat producers in Sub-Saharan Africa with a yearly estimated production of 4.6 million tons on 1.69 million hectares in 2017/18 with productivity of 2.74 tons per hectare (CSA, 2018). Wheat is mainly grown in the highlands of Ethiopia, which lie between 6-16° N and 35- 42° E, at altitudes ranging from 1500 to 2800 meters above sea level and with mean minimum temperatures of 6°C to 11°C exclusively under rainfed conditions (Engida, 2 001; MoA, 2012). Mean wheat yield increased from 1.3 tons ha-1 in 1994 to 2.74 tons ha-1 in 2017/18, far below experimental yields of over 5 tons ha-1 (Gete et al., 2010; Man and Warner, 2015). The average wheat productivity in SSA is 1.7 tons ha-1 (FAO, 2014), nearly 50% below the world average. The national wheat productivity in SSA varies across countries. It ranges from 0.7 tons ha-1 in Burundi to 3.4 tons ha-1 in Mali. The main wheat-growing areas of Ethiopia are the highlands of the central, south-eastern, and northwest parts of the country. However, Ethiopias current wheat production is insufficient to meet domestic needs, forcing the country to import 30 to 50% of its wheat demand to fill the gap (Minot et al., 2015). Several factors hindered the yield of wheat crops such as low soil fertility, lack of improved wheat varieties, and lack of improved management practices. The low yield is primarily associated with the depletion of soil fertility due to continuous nutrient uptake of crops, low fertilizer use, and insufficient organic matter application (Kidane, 2015). Continuous cropping and inadequate replacement of nutrients removed in crop harvest or loss through erosion and leaching have been the major causes of soil fertility decline (Hillete et al., 2015 Van Beek et al., 2016). This is particularly evident in the intensively cultivated high-potential areas that are mainly concentrated in the highlands of Ethiopia (Hillete et al., 2015). Nutrient balances in the highlands of Ethiopia, typically the high potential areas for agricultural production are currently exposed to severe soil fertility depletion (Van Beek et al., 2016). In addition, several factors such as improved varieties, adequate cultural practices like balanced fertilization, and management of other biotic and abiotic factors are very important for higher productivity of wheat (Alam and Jahan, 2013).
Yet, agricultural production is increasing which benefits farmers livelihoods and contributes to the food security of the country as a whole, but at the expense of the natural resource base (Van Beek et al., 2016). The yield gap of over 3 tons ha-1, suggests the potential for increasing production through improved soil and crop management practices, particularly increased use of fertilizers and adequate soil fertility maintenance program. Varieties are one of the other major factors that play an important role in producing higher yields of wheat (Alam and Jahan, 2013). Wise use of fertilizers increases crop yield and production; the reverse will lead to a decline in production and ecological imbalance. The fertilizer use efficiency of the crop depends on the performance-specific variety. So cultivar selection plays a very important role in determining grain yield and quality (Brian et al., 2007). In most of the nutrient studies in Ethiopia, more emphasis was given to macronutrients, especially N and P, and micronutrient investigations received little attention. However, Ethiopia is moving from blanket recommendations for fertilizer application rates to recommendations that are customized based on soil type and crop (Nicholas et al., 2015). This is a move towards diversification and inclusion of other types of fertilizers apart from DAP and urea, which have long been the only types of fertilizer imported for grain crops. Different recent studies have shown that elements like N, P, K, S, and Zn levels as well as B and Cu are becoming depleted and deficiency symptoms are being observed on major crops in different areas of the country (ATA, 2013). Most Ethiopian soils are deficient in macronutrients (N, P, K, and S) and micronutrients (Cu, B, and Zn) (EthioSIS, 2014; Sharif et al., 2019).
Even though different types of blended are suggested by EthioSIS, farmers in most parts of the country have limited information on the impact of different types and rates of fertilizers except that of blanket recommendation which is nitrogen at a rate of 41 kg N ha-1 and phosphorus at a rate of 46 kg P2O5 ha-1. Therefore, due to lacking such information, particularly on the use of appropriate fertilizer rates and best-performing variety in the district, the study was conducted with the following objectives:
1) To investigate an optimum agronomic practice of NPSB fertilizer rates and bread wheat varieties on different yield components and grain yield.
2) To identify the most profitable NPSB fertilizer rates and bread wheat variety for wheat production in the study area.
Description of Experimental Site
The experiment was conducted at Degam District during the 2019 main cropping period. The district is located 124 km North-West of Addis Ababa, and 12 km from Fitche, the capital city of North Shewa Zone, and Oromia Regional State. The district is bordered on the West by Kuyu, on the North-West by Hidabu Abote, on the North by Jama River which separates it from Amhara Region, on the North-East by Girar Jarso, and on the East by Yaya Gulele and Debre Libanos district (Fig. 1). Geographically, the district extends from 9°34 to 10°03N latitudes and 38°29 to 38°44E longitudes. The site is located at 9°4948.2′′ North latitude and 38°3343.8″ East longitude with an elevation of 3014 masl. The temperature varied between 5.6°C to 23°C. The annual rainfall ranges from 800 mm to 1300 mm and the rainfall pattern is bi-modal; a short rainy season (Belg) from February to March, and a main rainy season (Kiremt) that extends from June to September. The study area is characterized by Nitosol which is locally known as ‘Biye Dima and Biye Bore and Wheat is the major crop produced in the area (Anonymous, 2017).
Experimental Materials
Plant Materials
Dandaa (Danphe # 1), Hidase (ETBW5795), and Kakaba (Picaflor # 1) were used for the research study. The details of the three varieties are indicated in (Table 1). Those varieties are selected based on yield, disease resistance, farmers acceptance, and popularity character to the district.
Fertilizers Materials
NPSB fertilizer (18.9% N, 37.7% P2O5, 6.95% S, and 0.1% B), Triple super phosphate (TSP of 46% P2O5), and urea (46% N) were used as fertilizer sources.
Experimental Treatments and Research Design
Treatment combinations of three improved varieties (Dandaa, Hidase, and Kakaba) and five NPSB fertilizers rates [0, 50, 100, 150, 200, and NP (64/20) kg ha-1 of local control] with supplementation of 92 kg N for all treatment except blanket recommended NP and the control were used for treatments (Table 2). The experimental field study was arranged with a total of 18 treatments in a factorial combination with a complete block design (RCBD) in three replications.
Selected Physico Chemical Properties of Experimental Soil before Sowing
Results of research field soil anlysis before sowing for some physico-chemical properties showed the range level and nutrient contents as indicated below before the application of fertilizer to the field (Table 3).
The experimental research study indicated that application of balanced and sufficient soil nutrient management with high yielder improved variety is one of the best agronomic practice for increasing yield components and yield of bread wheat. Accordingly, analysis of the result revealed that 50% days to heading, total number of tillers, number of kernel per spike and grain yield were highly significantly affected by main effect of both varieties and NPSB fertilizers; Whereas spike length, above ground biomass yield and straw yield were significantly affected by the main effect of NPSB fertilizer rate while thousand kernels weight was affected only by the main effect of variety. However, the analysis of result study indicated that as days to 90% maturity, plant height and number of productive tillers were significantly affected by the interaction effect of both factors. The highest, maximum grain yield (4549 kg ha-1), above ground biomass yield (13.8 tons ha-1), straw yield (9.4 tons ha-1), number of kernels per spike (54.9), total number of tillers (5.6), number of productive tillers (4.7), the longest days to heading (82.4 days), physiological maturity (163.6 days), highest number of kernels per spike (54.9) and highest plant height (102.4 cm) were recorded at the maximum NPSB rate application (200 kg ha-1) supplemented with nitrogen fertilizers. While the lowest and minimum result for all parameters were recorded from unfertilized plot except for thousand kernels weight and harvest index. The result of economic analysis showed that combined production of 200 kg ha-1 blended NPSB fertilizer with Hidase variety gave economic benefit of 97993ETB ha-1 with the acceptable marginal rate of return (640.14%). Similarly, the grain yield also showed that statistically the highest grain yield (4979 kg ha-1) was obtained from the combined application of 200 kg ha-1 of NPSB fertilizer with Hidase variety. Therefore, it could be concluded that application of 200 kg NPSB in supplement of 92 kg N ha-1 fertilizer with Hidase variety was temporarily the best producing alternatives and economically profitability and with acceptable grain yield of bread wheat production at the study area. Finally it is advisable to undertake further research across soil types, season and locations involving others best performing cultivar to draw sound recommendation on a wider scale and for longer duration and variable cropping systems.
A.F.B.; L.A. designed the study. A.; and A.N.M. performed the methodology. A.R.I carried out the data analysis. D.Y.A composed the manuscript. All the authors checked and approved the final manuscript.
The authors acknowledged Oromia Agricultural Research Institute for funding experimental research. The authors also extend their gratitude acknowledgment to Fitche Agricultural Research Center for its financial support and providing working facility. The authors also express their special thanks to all staff members of Fitche Agricultural Research Center for their unreserved assistance in setting up, planting, collecting the data and maintaining the field experiments.
The authors declared that they have no any financial or persona conflicts of interest that can affect the report of this research paper.
Academic Editor
Md. Ekhlas Uddin Dipu, Managing Editor, Universe Publishing Group (UniversePG), Dhaka, Bangladesh.
Fitche Agricultural Research Center, P.O. Box 107, Fitche, Ethiopia.
Bedada AF, Akter L, Asaduzzaman, Mirza AN, Islam AR, and Alemayehu DY. (2024). Optimum determination of NPSB fertilizer rates on bread Wheat (Triticum aestivum L.) varieties. Int. J. Agric. Vet. Sci., 6(5), 105-118. https://doi.org/10.34104/ijavs.024.01050118