International Journal of Agriculture & Agribusiness
Publication Date: February, 2021
Tibebu Diro Gutema
Oromia Agricultural and Natural Resource Bureau
Northern Shewa Zone Agricultural and Natural Resource Office
Journal Full Text PDF: Effect of Organic Manure & NPK Fertilizer on Growth & Yield of Carrot (Daucus Carota L).
Abstract: Carrot is a root vegetable with high nutritious value. Total production in the country was 17,333.43 tons produced in 4,902.90 ha of land with 3.5 ton/ha productivity despite its suitable agro climatic for carrot production Soil needs continuous input of minerals from external sources. Because nutrients applied on to a growing crop are mainly consumed by plants for growth and development. But nutrients Left in the soil leach down and become unavailable to the next crop. Altering the soil nutrients and fertility status by providing a balanced and adequate dose of major nutrients like nitrogen, phosphorus, and potassium as per the crop requirement, is one of the easiest ways to boost up the growth and yields of carrot. But, the use of excessive use of chemical fertilizers for increasing production resulted in imbalanced and heavy removal of nutrients from the soil, sick soils and the population of beneficial microorganisms also gets highly affected. Not only imbalanced, but the application of balanced inorganic fertilizer also does not sustain the soil because of leaching losses. Nowadays the demand for ‘organic’ food and health concerns is increasing. As a result, the application of chemical fertilizers has realized the need for the application of organic manure to meet the increasing requirements of growing plants. The use of organic fertilizers may increase growth and yields of carrot. But, the application of only organic manures does not meet the nutrient demands of the crop during the initial phase of crop growth because of their slow release available nutrient. But not satisfactory research conducted on the production of carrot by using integrated fertilizers. In Ethiopia, growers/producer don’t have sufficient information about using appropriate integrated fertilizers. It is therefore further much more research will be needed to better define the organic manure and chemical fertilizers requirements for carrot production and productive. This review briefly presents the use of the application of chemical fertilizers and different organic manure fertilizers for sustainable growth and yields of carrot.
Keywords: Organic manure, NPK fertilizers, growth and yield of carrot.
Carrot (Daucus carota L.) belongs to the family Apiaceae (previously Umbelliferae). It instantly became embraced wherever it appeared after it was carried out from its home in Iran and Afghanistan. During its journey across centuries and continents, countless botanists managed to improve the composition, look, flavor and size of ancient carrots and produce the modern orange colored carrot that appeared first in 17th century Netherlands. Home of carrots and its numerous cousins can be tracked to dry and hot lands of Iran and Afghanistan. The earliest evidence of its use there was dated to 3000 BC. From there, carrot seeds were picked, carried and sold via caravans to neighboring Arabian, African and Asian lands, who all accepted carrots immediately and started cross-breeding and creating new types of this famous root. Even in those ancient times, many colors of carrots were present and used black, white, red and purple. Interestingly, the orange colors that we use today were not present.
The most telling sign of how popular carrots were in those ancient times come from Ancient Egypt, where numerous carrots were placed in the tombs of dead Pharaohs and the drawings of the carrot harvest and processing can be found in numerous hieroglyph paintings. The most popular color of carrots that were cultivated in Egypt was purple, and it was used not only for eating but also for medicine. The tradition of medicinal carrot usage moved from Egypt to Greece and Rome in 1st millennia BC. There, bitter and hard to eat carrots were used as a healing remedy for many illnesses, and was especially used as a sexual aphrodisiac (the most famous recorded instance of such use happened during the reign of Roman emperor Caligula). As for eating in regular meals, Romans were known to boil carrots and eat it with live dressings and various herbs. By 13 century carrots traveled from Persia to Asia, reaching distant Japan. During the same time, European carrot started being cultivated in gardens and fields of France and Germany. Those carrots were biter, but they were nutritious and its popularity enabled quick spread across entire Europe. In 1609, English settlers of the New World started cultivating Carrots in their first city of Jamestown, Virginia (20 years later production moved to Massachusetts. Brazil was the first South American country to receive carrots in the mid-17th century, and not much later the carrot arrived in Australia.
Modern yellow carrot appeared in the Netherlands during the 17th century as a tribute to the ruling House of Orange. After years of selective breeding, Dutch yellow carrot was engineered to be without bitterness, increased sweetness and minimal wooden core. American cuisine did not include carrots for the longest of times. It was accepted to the American homes only after World War I when soldiers returning home brought stories and seeds of incredible French and another European cuisine which greatly help them to survive war years. and by the yearly 20th century they became the predominate carrots in most growing regions of the world.
According to Ethiopian Central Statistical Agency (2017/18), carrot total production in the country was 17,333.43 tons produced in 4,902.90 ha of land with 3.5 ton/ha productivity despite its suitable agro climatic for carrot production. This productivity is relatively very low compared to world average (21 t/ha) and other carrot producing countries Switzerland, Denmark, UK, Sweden, Austria and Israel, where the average per hectare yields are reported to be 40.88, 42.67, 51.88, 54.35, 56.7 and 64.2 tones, respectively (Kahangi, 2004; FAO, 2000). In view of this, a lot of work has to be done in Ethiopia to improve carrot productivity. Integrated nutrient application is useful to fill this gap as imbalanced use of fertilizers leads to loss of soil fertility and adversely impacted agricultural productivity as well as causes soil degradation (Patil et al., 2016; Thiruneelakandan and Subbulakshmi, 2014; Vithwel and Kanaujia, 2013.). In Ethiopia, carrots are usually grown on small plots in the backyards of town and peri-urban dwellers mainly for family consumption.
Carrots grow best in full sun but tolerate some shade (Elzer, 2014) with the optimum temperature of 16 to 21 °C (61 to 70 °F). The ideal soil is deep, loose and well-drained, sandy or loamy of fertile with a pH of 6.3 is more preferable. Heavy soils need to be amended with plenty of compost to allow good root development. However, hairiness and thick root development from taproot in the compost. Prepare the soil before planting; incorporate up to 2-4 inches of well-composted organic matter. They require low levels of nitrogen, moderate phosphate, and high potash. Plants grow best 1000 m up to 2800 meter above sea level in the central highlands.
Its root is valued as food (salads, soups, steamed or boiled in other vegetable dishes) mainly for its high carotene content. Carrots have gained worldwide acceptance due to their high vitamin A content, acceptable taste, ease of production and relatively long storage life at low temperature (Ali et al., 2006)
Although inorganic fertilization is very important for the healthy plant growth and development, the organic source of nutrients has the advantage of consistent and slow release of nutrients, maintaining ideal carbon: nitrogen (C: N) ratio, improvement in water holding capacity and microbial biomass of soil profile, without any adverse residual effects (Kiros et al., 2018; Yadav et al., 2010). Also, a mixture of inorganic and organic fertilizers has the ability to produce thick carrot root tubers. Early vegetative growth was greatly enhanced by higher doses of Nitrogen fertilizer (Hailu et al.; 2008)
The objective of the Study
The main objective of this review was to assess the effect of organic manure and NPS on growth and yield of carrot the specific objectives of the study were:
o To assess current farming practices and synthesize major potential and constraints in garlic production practices
o To evaluate bulb yield and yield component of carrot at organic manure and NPS fertilizer.
2 Nutrient Requirement of Carrot
Crops fulfill their nutritional requirements from the uptake of minerals mostly through soil (Cakmak, I.,2002) Soils of the crops growing areas have an ability to minimally sustain the plant growth with the nutrients held from previous crop rotation. However, these nutrients are not in sufficient amounts to fulfill the increasing requirements for higher production [Sediyama et al,2011]. Applied nutrients on a growing crop are mainly consumed by crops for growth and development. Left over nutrients in the soil leach down and become unavailable to the next crop. Due to this, soils in the crops growing areas do not hold sufficient quantity of nutrients to provide the amounts required by the plant for sustainable production and yield. The most abundant nutrient element absorbed from soils and subsequently removed in vegetable crop harvests is nitrogen (N) (Brandenburg, W. 1980). The main N forms absorbed by plants are ammonium (NH4+) and nitrate (NO3-) N. Some plants show preferences for either NH4+ or NO3-. Explanations to account for these preferences have been presented by (Haynes & Goh Haynes, R. J.; Goh, K. M. 1977). Ammonium and NO3- nutrition of plants directly influences the growth and yield a chemical composition of vegetables. The latter, in turn, may affect the health of the consumers (Lorenz, O. A. 1978)
2.1 Mineral fertilizers in Carrot
The yield and yield contributing characters of carrot were influenced by the application of organic fertilizers. Hossain mentioned that, the highest marketable yield was obtained by the application of NPK fertilizers 140 kg, 40 kg and 80 kg ha-1 respectively (Hossain, 2005). Nitrogen 200 kg ha-1 produced the tallest plant, a maximum number of leaves, cracked roots, branched roots and fresh shoot weight but nitrogen 150 kg ha-1 produced the maximum root length, root diameter, fresh root weight and the highest yield 53.37 t ha-1 (Haque, 1999). But indiscriminate use of inorganic fertilizer changes the physical, chemical and biological properties of soil and creates problems to the environment and health hazards due to the toxic residual effects.
The most commonly used fertilizer levels were N which was ranged between 75 – 150 kg. ha-1, 25 – 125 kg. ha-1 of P and 0 – 175 kg. ha-1 of K.
Partha and Sivasubramanian 2006 mentioned that press mud can be used as a source of fertilizer for better production of crops. Baloch et al recorded highest carrot yield (29.7 t ha-1) with high levels of NPK viz 100kg N, 100 kg P and 125 kg K ha-1. Cheuk et al. 2003 investigated the effect of waste management on vegetables and found that the application of agricultural wasted increased the yields of tomato and pepper up to 10%. Khan and Khan 2006 produced the highest yield (12.00 t ha-1) by using NPK (120-90-60kg ha-1) in carrot. Root length (cm), root diameter (cm) and root weight plant (g) of carrot as affected by applying recommended doses of different organic manures 1 and inorganic fertilizers, for two consecutive years.
2.2 Organic Fertilizer
Considering the adverse effects on soil health and the environment, besides the residual effect, excessive usage of inorganic fertilizers is not advisable. The main sources of organic matter are; cattle dung, urine, litter, crop residues/waste like sugarcane trash, straw, poultry, sheep and goat dropping, waste from fruit and vegetables, press mud from sugar industries, rice husk and bran/dust from textile industries. These all organic matter can be used for building up and maintaining organic matter in the soil to conserve fertility and as well as soil physical condition to increase the fertilizer use efficiency (Khan et al, 2007). Manure is considered as the key to restoring the productivity of degraded soils as it supplies multiple nutrients, raises soil pH and improves soil organic matter which in turn improves the physical and microbial properties of the soil (Zingore et al.200)
Among organic manures, the nutrient content of poultry manure is, among the highest of all manures, and the use of poultry manure as a soil amendment for agricultural crops provides appreciable quantities of all-important plant nutrients (Sims and Wolf,1994). Poultry manure is relatively resistant to microbial degradation, but it is essential for establishing and maintaining optimum soil physical condition and important for plant growth. As well as it is also very cheap and effective as a good source of N for sustainable crop production, Poultry manure as an organic material is particularly important since its conditions and improves soil fertility and contains all macro-nutrients and most of the micro-nutrients (Duncan, 2005). However, damage to crops and pasture were reported, when poultry manure is applied at high rates (>18 t ha-1) (Edwards and Daniel, 1992). Similarly, high application rate of poultry manure (18 t ha-1) to loamy sand was reported to increase the concentration of nitrate at 3 m depth from 15 to 179 mg NL1 (Liebhardt, 1979) and an increased concentration of nitrate at 120 cm depth in a silt loam soil (Adams. et al, 1994) The use of poultry manure in promoting organic farming and in enhancing soil fertility has profound implications in the agricultural production, as well as socioeconomic status of rural livelihoods in the developing world as some city dwellers sells manure for their living income (Mufwanzala and Dacanay, 2010)
Poultry manure has frequently been found to increase the yields of pastures and crops including vegetables (Edwards and Daniel, 1992). Maintenance and management of soil fertility are central to the development of sustainable food systems (Prasad, and Power, 2005), and also contains higher nitrogen and phosphorus compared to other bulky organic manures. The average nutrients contents in poultry manure are N-3.03%, P-2.63% and K-1.4% Guled et al. 2003. Adediran et al. 2003 compared poultry manure, household, market and farm waste, and found that poultry manure had the highest nutrient contents and gave the greatest increased yield of the crops and soil macro and micronutrients content. (Adediran, et al. 2003) found that poultry manure significantly increased soil pH, N, phosphorous, potassium, calcium and magnesium and nutrient uptakes in plants. The addition of poultry manure to cultivated land helps to recycle nutrients and reduce fertilizer costs in crop production systems. In addition, application of poultry manure or other organic wastes may also generate a positive residual effect that should be taken into account for the succeeding crops (Eghball et al., 2004) Use of poultry manure or other animal manure not only increases the soil inorganic N pool but also increases the seasonal soil N mineralization available to the crops (Ma, et al., 1999) Application of farmyard manure and incorporation of rice and wheat straw improved physical and chemical properties of soil. Maskey and Bhattarai 1984 reported that the nutrient value of organic manure such as farmyard manure and compost depend upon the composition of animal feed, fodder, bedding materials, methods of preparation, length and condition of storage, etc. They reported that the nutrient content of farmyard manure and compost prepared under farmers‟ condition may vary from 0.5-1.4 % N, 0.4-2.4 % P, and 0.5-3.5 % K as calculated on oven-dry basis. Carrots, unlike most other vegetable crops, have not traditionally had animal manures, such as poultry manure, applied before planting or as a side dressing, for fear of root forking. Research trials have indicated increased yield and advanced maturity using poultry manure as a pre-planting treatment without increasing the percentage of root forming (Phillips, et al. 2002). (Aliyu 2000) reported that the use of farmyard manure plus poultry manure at 5 t ha-1 resulted in higher fruit yield of eggplant.
(T. A.Mehedi et al. 2012) were reported that different parameters of growth and yield were significantly affected due to different levels of cow dung manure. The organic matter, total nitrogen, phosphorus, potassium content of the experimental plot was 1.68%, 0.10%, 14 ppm and 0.18 me/100 g soil respectively carried out. Organic manure increased the water holding capacity of the soil, kept soil loose and friable which are desirable for the carrot.
In recent times, the study showed that organically grown fruits or vegetables contain more mineral and vitamins than conventionally grown ones (Bourn and Prescott, 2002). A report by About et al., (2012) showed that vegetative growth and yield of different crops were increased with the addition of organic cattle manure. Several attempts have been made to increase the yield potential of root crops neglecting carrot. In addition, previous research was only concerned with the use of inorganic fertilizers. However, this type of fertilizer if endlessly used by farmers it results in loss of soil fertility and soil health.
Cattle manure being bulky organic material releases the soil compactness and improves the aeration in addition to the supply of essential plant nutrients and organic matter and increases soil microbial establishment along with the accumulation of excess humus content (Greene, 2007). Organically produced fruits, vegetables, food crops fetch much higher value not only in the international market but also in the domestic market. They are known to be devoid of any residues, thereby having a positive impact on the environment and human health. The research pertaining to the use of organics and biofertilizers in vegetable crops particularly in carrot is very much limited (Leclerc et al. 1991; Warman and Harvard 1996; Warman and Harvard, 1998; Stone, 1998). Specific recommendations about the use of organic fertilizer (cattle manure) are lacking in our country Ethiopia.
GRAPH 1: EFFECT OF DIFFERENT COW DUNG ON YIELDS OF CARROT
GRAPH 2: EFFECT OF DIFFERENT COW DUNG ON THE GROWTH PARAMETER OF CARROT
Source: Iikadu & Refisa 2019
One of the appropriate processes for organic fertilizer production is vermicomposting which converts organic materials (usual wastes) into a humus-like, finely divided, nutrient-rich material known as vermicompost. Vermicomposting technology, using earthworms as versatile natural bioreactors for effective recycling of organic wastes to the soil, is an environmentally acceptable means of converting waste into nutritious composts for crop production. Earthworms make the soil „soft and porous‟ by its burrowing actions and excretions containing nutrients with beneficial soil microbes to improve its natural fertility and productivity. In Ethiopia, vermicompost application is getting more emphasis accounted for ease of preparation, input and labor availability, better nutrient composition as well as low cost as compared to inorganic fertilizer (Shanu et al. 2019; Almaz et al., 2017; Girma and Zeleke, 2017; Tesfaye, 2017; Devi et al., 2007).
TABLE 1 CONTRIBUTION OF VERMICOMPOST ON GROWTH PARAMETER OF CARROT
2.3 Integrated nutrient management
The basic concept pertinent to the principles of integrated nutrient management is the maintenance and possible management of soil fertility for sustaining crop productivity on a long-term basis (Hedge and Srinivas, 1989).
Many factors are responsible for carrot low production, but the non-availability of nutrients in the soil is one of the basic constraints. Ethiopian is having imbalanced soil fertility and thus to get better production, it is the basic requirement to enrich our soils with the nutrients to fulfill the requirement of crops for their better growth and yields. Balanced fertilization is one of the most important factors in maximization is one of the yield potentials of various crops. The nutrients are either added to the soil by using chemical fertilizers or by incorporating natural organic manures. The use of mineral fertilizers is the quickest way of increasing crop production; almost 30 to 70% increase in yields of crops has been achieved through the use of optimum and balanced mineral fertilizers. (Ahmad, N. and A. Hamid, 1998). High output from limited resources and intensive farming results in the accelerated use of chemical fertilizers, which pose certain threats to the environment and to humans (Zhu, Z.L. and D.L. Chen, 2002). Limitations in the food supply for an ever-increasing population are a major challenge for agricultural researchers (Saez, C.A., et al 2012). In the recent past, the intensive use of chemical fertilizer was one of the most tools for getting a higher yield for food security. To get a high yield by limiting the use of chemical fertilizers and supplementing them with organic-based fertilizers is a new concept for sustainable agriculture. Organic waste serves not only as a source of plant nutrients but also in restoring soil fertility and soil quality, thereby improving the chemical, physical and biological properties of soil (Tennakoon, 1995). A major component of organic production is providing organic sources of nutrients to promote plant growth as well as sustain soil quality (Dimitri, C. and C. Greene, 2002). As well as, organic manures and inorganic fertilizers substantially increase all growth and yield parameters like leaves per plant, leaf length(cm), leaves weight per plant, root length (cm), root diameter (cm) root weight per plant, biomass weight per plant, and yields (t ha-1) of carrot
Several works have documented positive effects of organic manures as akanni and ojeniyi reported significant improvement in the production amaranths and tomato by sole application of poultry manure and goat manure, respectively (Akanni, D.I., and S.O. Ojeniyi, 2008). As well as Several scientists are advocating the integrated nutrient management with organic and inorganic fertilizers to conserve the soil health and to get good quality produce (Rani and Mallareddy, 2007).
The importance of organic and inorganic nutrients for the better production of carrot. Also, a mixture of inorganic and organic fertilizers has the ability to produce thick carrot root tubers. Early vegetative growth was greatly enhanced by higher doses of Nitrogen fertilizer (Hailu et al.; 2008). The resent work was undertaken to study the effect of recommended rates of different organic manures including farmyard manure, poultry manure, goat manure, press mud, and sewage sludge and inorganic fertilizers (NPK) on the yield and yield contributing traits of carrot.
TABLE 2 RESULTS OF ORGANIC AND IN ORGANIC FERTILIZER ON GROWTH AND YIELDS OF CARROT
In general, fertilizer integration positive effect on yield could be attributed to the positive effect of all the yield components, root girth, fresh weight and dry weight of root. Furthermore, this increased yield may be due to better availability and uptake of nitrogen and other nutrients in a combination of vermicompost which might have led to the balanced C/N ratio and increased activity of plant metabolism. Combined usage of organic fertilizers with inorganic fertilizers not only helps to improve the yield and quality of carrot but also help in conserving the soil health (Mazgabu, 2019)
Table 4. Effect of nitrogen and vermicompost levels on carrot growth parameters
3 Summary and Conclusion
Adequate use of mineral fertilizers and organic manures is of high importance for obtaining maximum yield and growth of produce in one hand and on the other hand prevention of adverse effects on soil health and environment Organic inputs are often proposed as alternatives to mineral fertilizers. However, the farmers organic inputs, crop residues, and animal manures cannot meet crop nutrient demand over large areas because of the limited quantities available, low nutrient content of the materials, and the high labor demands for processing and application. Therefore, most farmers in Africa include Ethiopia fall within the two extremes of the organic to inorganic fertilizer continuum and use a combination of organic and inorganic inputs. Furthermore, it is difficult to make precise recommendations for chemical fertilizers unless they are site specific since the reports for various fertilizer experiments are quite variable. The model of application of a combination of organic manure and chemical fertilizers has shown remarkable effects of yield and quality. Because manure and chemical fertilizers have a potential role in the growth and development of crops. As a result, integrated use of organic manure and chemical fertilizers is valuable for optimum yield potential, root quality, and environment-friendly sustainable farming systems and an increase of profit margins for growers. An appropriate combination of chemical fertilizers and organic manures is a possible way-forward to achieve reasonable yield and quality. But since there is no satisfactory research conducted on the production of carrot growers don’t have sufficient information about using appropriate agricultural practices and rates of recommendation.
Use of integrated nutrient fertilizer management is the maintenance of soil fertility for sustaining carrot production and productivity. But not satisfactory research conducted on the production of carrot by using integrated fertilizers. In Ethiopia, growers/producer don’t have sufficient information about using appropriate integrated fertilizers. It is therefore further much more research will be needed to better define the organic manure and chemical fertilizers requirements for carrot production and productive.
I would heartedly like to thank and praise the Lord Almighty God in giving me strength and Wellbeing to successfully complete this review. I sincerely thank Dr. Ashenafi Chaka for all the necessary support and advice. Also we would like to thank Ambo University College of Agriculture and Veterinary Sciences for developing this course in the M.Sc. The curriculum of Horticulture. Finally, all the reference materials used in this review paper are dully acknowledged.
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