Effects Of Organic Biofertilizer Performance On Cowpea (Vigna unguiculata)

FPA/AT/21/3-0045

 

SUBMITTED TO:

DEPARTMENT OF AGRICULTURAL TECHNOLOGY

SCHOOL OF AGRICULTURE AND AGRICULTURAL TECHNOLOGY

THE FEDERAL POLYTHENIC ADO-EKITI

IN PARTIAL FULFILMENT FOR THE REQUIREMENT FOR THE AWARD OF HIGHER NATIONAL DIPLOMA (HND) IN AGRICULTURAL TECHNOLOG (CROP PRODUCTION)

NOVEMBER, 2023

 

CERTIFICATION

This is to certify that OLANISIMI, BABATUNDE OLAREWAJU with matriculation number FPA/AT/21/3-0045 carried out this research work titled “Effects Of Organic Bio-fertilizer Performance On Cowpea (Vigna unguiculata)” in satisfying fulfillment of the requirement for the award of Higher National Diploma (HND) in Agricultural Technology (Crop Production) The Federal Polytechnic Ado-Ekiti.

 

Dr. Isaac Oyewusi ________________________

(Supervisor)  (Signature and Date)

 

 

 

Dr. Jimoh O.A      _______________________

(Signature and Date)

 

 

External Supervisor      _______________________

   (Signature and Date)

DEDICATION

I dedicate this project to the creator, and to my late mother, my strong pillar, my source of Inspiration, wisdom, knowledge and understanding. She has been the source of my strength throughout this program and on her wings only have I soared.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ACKNOLEGEMENT

My deepest gratitude goes to creator who has provided all that was needed to complete this project and the program for which it was undertaken for. There was never lack or want. Throughout this entire study, He took care of everything that would have stopped me in my tracks and strengthened me even through my most difficult times, all of whom I have had direct contact with and who have impacted me during this program. I say a big thank you. My sincere appreciation to the entire family of Fayase, Ajasa family(USA), the entire family of Ayuba (UK), my beautiful fine wine, Garuba Ayobami, my silblings; Ayo, Joy, faith, success, marvellous, David, convennt, Desire, Adejugbe family, Adeoti family, Aderinboye family, Oduntan Ademola all my Couse mate most especially Ejeh Friday, Ogunola wasiu who has encouraged me all the way and whose encouragement has made sure that I give it all it takes to finish that which I have started.

Finally, I thank my Project supervisor, Dr. Isaac Oyewusi for his words of motivation and words of comfort that come in just in time. You won’t lose your reward. Amen.

 

 

 

 

 

 

 

TABLE OF CONTENTS

Title page Page

Certification        ii

Dedication iii

Acknowledgement iv

Table of Content     v

List of Tables            vii

Abstract viii

CHAPTER ONE

1.1 INTRODUCTION 1

1.2 Statement of the problem 1

1.3 objectives of the study 2

1.4 Significance of the study 2

1.5 Justification of the study 3

1.6 Limitation of the study 3

CHAPTER TWO

2.0 LITERAURE REVIEW   4

2.1 The need for legumes rhizobia nodulation system in conjuction with biofertilizer 4

2.2 The potentials of different typrs of biofertilizer on crop growth and development 5

2.3 Super-Gro biofertilizer 6

2.4 Boostract organic biofertilizer 6

2.5 Assessment of super-Gro biofertilizer with other fertilizer 7

2.6 Comparative effects of organic based fertilizer and mineral

fertilizer on dry matter yield of cowpea 8

2.7 Integrated Impact of Organic and Inorganic Fertilizers on Growth,

Yield of cowpea and Soil Properties 9

CHAPTER THREE

3.1 MATERIALS AND METHODS  12

3.2 Site description 12

3.3 Experimental design and treatment. 12

3.4 Growth and yield Parameters measured 13

3.5 Characteristics of Bio fertilizers used for the experiment 14

CHAPTER FOUR

4.0 RESULT AND DISCUSSION 16

CHAPTER FIVE

5.0 CONCLUSION AND RECOMMENDATIONS 29

5.1 Conclusion 20

5.2 Recommendation 29

References 30

 

 

 

 

 

 

 

 

 

 

 

 

LIST OF TABLES

Table 1: Effect of organic biofertilizers on plant height of two cowpea varieties 16

Table 2: Effect of organic biofertilizers on number of leaves of two

cowpea varieties 18

Table 3: Effect of organic biofertilizers on number of branches of two

cowpea varieties 20

Table 4: Effect of organic biofertilizers on stem girth of two cowpea varieties 22

Table 5: Effect of organic biofertilizers on leaf area development of two

cowpea varieties   23

Table 6: Effect of biofertilizers on yield and yield characters of two

cowpea varieties 24

Table 7: Physical and chemical properties of the soil at experimental site. 26

 

ABSTRACT

The experiment was conducted in the Teaching and Research Farm of the Department of Agricultural Technology of the Federal Polytechnic, Ado-Ekiti in June, 2023. The experiment was carried out to evaluate the potentials of different organic biofertilizers on performance of cowpea. The experiment was a 2 x 4 factorial combination arranged in a randomized complete block design. Treatment consisted of the use of Super Gro Biofertilizer, (SPG), Boostract bio fertilizer, (BTB), the combination of SPG+BTB and a control (CLT) while the cowpea varieties included an improved variety (IT89KD-288) and an indigenous variety (Oloyin Brown). Two seeds each of the tested cowpea varieties were planted on a seed bed measuring 2mx2m in a plot of 20mx10m. The study concluded that the use of organic biofertilizers can improve the growth, yield, and quality of cowpea varieties. Combinations of Super Gro and Boos tract biofertilizers provide better results than their individual application. The result shows that days to first flowering were significantly shorter with application of biofertilizers while the improved cowpea variety gave superior attributes over the indigenous cowpea variety. In addition, highest yield was recorded for IT98KD-288 (509.6kg/ha) over other treatments with the combination of SPG+BTB. Improved IT89KD-288 performed better than Oloyin Brown for growth and yield characters. Therefore, the study recommends the use of biofertilizers as a sustainable alternative to synthetic fertilizers in cowpea production. Further studies are required to investigate the effects of biofertilizers on cereal crops. Therefore, the study recommends the use of biofertilizers as a sustainable alternative to synthetic fertilizers in cowpea production. Further studies are required to investigate the effects of biofertilizers on cereal crops. The study also recommends the combination of Super Gro with Boostract organic Biofertilizer as a good alternative to synthetic fertilizer to enhance crop growth and yield.

INTRODUCTION

CHAPTER ONE

1.1

Cowpea (Vigna unguiculata L.) is an important legume crop with a high nutritional value and an essential source of protein for humans and livestock. Cowpea plays a significant role in food security and poverty reduction in developing countries. However, the productivity of cowpea in many regions is still limited due to challenges such as inadequate soil fertility management, pest and disease infestation, and adverse weather conditions (MoyinJesu and Akanbi, 2014). In response to these challenges, researchers have explored various methods of improving the yield and quality of cowpea, including the use of organic biofertilizers. Organic farming is an agricultural system which relies on natural sources and processes Ezeaku et al,( 2014). Organic Bio-fertilizers have a potential role in improving soil fertility and crop growth Kumar et al, (2015). Bio-fertilizers are microorganisms that enhance plant growth by solubilizing nutrients in the soil and producing phytohormones, vitamins and enzymes Jat et al, (2014). Legume crops form an important part of agricultural cropping systems and are often grown for their high protein content. The use of organic Bio-fertilizers can have a significant impact on growth and yield of legume crops (Dauda et al, 2013). Bio-fertilizers have been used in legume crop production for many years as they increase the yield of crops through different mechanisms. Organic Bio-fertilizers are important in developing sustainable agriculture practices.

1.2 Statement of the Problem:

The use of synthetic fertilizers and pesticides in cowpea production has become a common practice, but their long-term use may result in soil degradation, environmental pollution, and human health hazards. This study aims to evaluate the effect of organic biofertilizers on the performance of two varieties of cowpea and to assess their potential as an alternative to synthetic fertilizers. The use of inorganic fertilizers has been discouraged due to its association with reduced yield, nutrient imbalance in the soil and pollution of ground water (Sridhar and Adeoye, 2003). There is therefore the need for the use of other fertilizer sources. Bio-fertilizer is useful substitutes to inorganic fertilizers which improves the soil quality. According to Narkhede et al., (2010), due to increase in prices rate of fertilizers in developing countries, the poor farmers are getting highly affected. The use of chemical fertilizers for a long time has resulted in poor soil health, reduce production, and increase in incidences of pest and disease and environmental pollution (Dauda et al 2018). For yield expansion of cowpea in Nigeria, there is a great need to augment the production of the crop by improving the fertilizer status of the soil in order to meet up with the nutrient requirement of the soil. This can only be achieved by the use of organic bio-fertilizers to enhance crop production and yield.

   1.3 Objectives of the Study:

The objectives of this study were to:

1. Determine the effect of Super Gro and Boostract Bio Fertilizer on the performance of two varieties of cowpea.
2. Evaluate the effect of combining both bio-fertilizers on the performance of cowpea varieties
3. Assess the potentials of bio-fertilizers as an alternative to synthetic fertilizers in cowpea production.

1.4 Significance of the Study:

This study will provide valuable information that could guide farmers and researchers towards a sustainable approach to cowpea production. It will also contribute to the body of knowledge on the use of organic biofertilizers in legume production and their impact on soil fertility and crop yield. Furthermore, the study results could encourage the adoption of biofertilizers in agricultural practices, leading to a reduction in environmental pollution and human health hazards.

1.5 Justification of the Study:

The use of synthetic fertilizers is a common practice; however, the negative impacts associated with their use have been widely documented. There is a growing need to explore and adopt more sustainable agricultural practices such as the use of organic biofertilizers. This study will provide evidence-based data to support the adoption of biofertilizers and their potential as a more sustainable alternative to synthetic fertilizers. The bioactive compounds present in biofertilizers are Anti-Microbial so they deter pest and diseases (Sharma et al, 2015).  It contains nutrients which enhance rapid and stable growth. Organic fertilizers improve the soil texture, allowing it to hold water longer. It increases the bacterial and fungal activity in the soil. It boosts both nutrient efficiency and organic matter content in the soil (Sharma et al, 2015). It nurtures the soil with organic matter that reduces dependency on chemical inputs. It restores and maintains soil fertility to nurture plant growth (Dauda et al 2018).

1.6 Limitations of the Study:

The study was conducted at the teaching and research farm of the department of Agricultural technology, and as such, the results may not be fully applicable to greenhouse conditions. The study also used a limited number of treatments and varieties, and therefore, the results may not be representative of the full range of biofertilizers and cowpea varieties.

 

CHAPTER TWO

2.0                                      LITERATURE REVIEW

2.1 The need for Legume-rhizobia nodulation system in conjunction with biofertilizers

Bio-fertilizers increase the nutrient status of the soil which in turn increases the growth and development of legume crops. Bio-fertilizers application improves soil structure, nutrient status and enhances soil microbial activity, uptake and efficiency of the nutrients to the crops Umaña et al., (2020). For example, Rhizobium inoculations improve the microbial diversity of the soil, resulting in higher soil fertility (Moyin-Jesu and Akanbi, 2008). Therefore, application of bio-fertilizers improves soil quality parameters like pH, organic matter, nitrate, phosphate, potassium and other parameters crucial for legume growth and development.Bio-fertilizers application to legume crops has shown a significant impact on crop yield and growth. According to Ndor et al. (2012), the application of Rhizobium, Azotobacter and Pseudomonas spp. improved the growth, nodulation and yield of green gram. Similarly, Rhizobium inoculation showed significant increase in growth, biomass and yield in chickpea (Jedidi et al., 2016). The application of Arbuscular mycorrhizal fungi (AMF) to legume crops has also shown a positive effect. AMF association improves nutrient uptake, which in turn increases the biomass and yield of the legume crops Odedina et al, (2003).The association between legumes and rhizobia is well known and considered critical for the growth and development of legumes. Nitrogen fixation in legumes is enhanced by the presence of rhizobia through the use of symbiotic interaction that occurs between the two. Nitrogen fixation by rhizobia aids in the improvement of soil nutrients, nitrogen uptake by crops and yields. Azospirillum sp. is also important for nitrogen fixation as it has been shown to be associated with root hairs of legume crops resulting in improved plant growth (Ojeniyi et al, 2010). Biofertilizers have been shown to enhance the symbiotic relationships between the legume crop and the rhizobia which in turn enhance nitrogen fixation and overall crop growth.

2.2 The potentials of different types of biofertilizers on crop growth and development

In recent years, the importance of organic farming and natural fertilizers has been growing steadily. Super Gro and Boos tract Bio Fertilizers are two organic fertilizers that are gaining popularity among farmers and gardeners alike. These fertilizers are believed to improve plant growth and yield by providing the necessary nutrients for plants to grow. In this literature review, we will look at their effect on plant nutrient requirements and how they compare with other fertilizers.
Odedina et al, (2003). The rampant use of inorganic fertilizers on our soils has caused soil nutrient depletion, acidification, loss of structural stability and genetic homogenization of crops, this has indeed threatened the air we breathe, the water we drink and the land we and others depend on for food and habitat. It has also been observed that fertile agricultural soils have become severely degraded as a result of slash and burn agriculture and shortened fallow period Dauda et al,( 2018). Therefore, an optimal and sustainable production of crops especially cowpea which needs relatively high soil fertility with particular reference to nitrogen, phosphorus and potassium will require some external organic materials which are found to be environmentally friendly, cheap and readily available Dauda et al, (2018) also advocated the use of external inputs from organic and inorganic sources on tropical soils for sustainable and improved soil management. However, the fertilizing value of Cocoa pod husk (ash and milled form) in okra production is yet to receive attention in Nigeria, whereas large quantities of these materials are dumped at various cocoa farms in all the cocoa growing zones of Nigeria. It has been observed that more than 33% of the world population majority of who are inhabitants of Sub-Sahara Africa suffers from hidden hunger ‘arising from malnutrition of deficiencies of some essential vitamins, minerals and other micro nutrient elements required for normal growth and functioning of body system. These essential elements are found in abundance in fruit and vegetable crops such as Oranges, apples, watermelon, okra etc. Cowpea is a good source of calcium (Ca) and magnesium (Mg) which help to prevent both Ca and Mg deficiencies, improve heart health, vision, lowers cholesterol, stabilizes blood sugar, aid digestion and supplies good amount of protein in our diet.

2.3 Super Gro Biofertilizers

Super Gro is an organic fertilizer that contains a variety of nutrients that are important for plant growth. It contains humic acid, which is a natural compound that improves soil structure and increases nutrient uptake by plants Akanbi et al, (2013). It also contains chelated micronutrients, which are minerals that are bound to organic molecules, making them easier for plants to absorb (Akanbi et al, 2012, Moyin Jesu, 2007). Super Gro is also rich in nitrogen, phosphorus, and potassium, which are the three macronutrients that are required in large amounts by plants.
Studies have shown that Super Gro can improve plant growth and yield, especially in crops such as cowpea, tomatoes, and pepper (Akanbi et al, 2010). In a study conducted by Kosir et al, (2020), Super Gro was applied to lettuce plants, and it was found that it significantly increased the plant biomass, leaf area, and nutrient content of the plants. This suggests that Super Gro can improve the nutrient uptake of plants, leading to better growth and yield.

2.4. Boostract Organic BioFertilizers:

Boostract Bio Fertilizers are another organic fertilizer that is gaining popularity. These fertilizers contain a mixture of beneficial microorganisms, such as bacteria and fungi, which help to improve soil health and nutrient uptake by plants Dauda et al,( 2018). These microorganisms can help to fix atmospheric nitrogen, making it available to plants, and they can also solubilize phosphorus, making it easier for plants to absorb Kumar et al., (2015).

Studies have shown that Boostract Bio Fertilizers can improve plant growth and yield, especially in crops such as rice, wheat, and corn (Kumar et al., 2015; Zhao et al., Deksissa et al, 2008). In a study conducted by Kumar et al. (2015), Boos tract Bio Fertilizers were applied to wheat plants and it was found that they significantly increased the plant height, biomass, and grain yield of the plants. This suggests that Boostract Bio Fertilizers can improve the nutrient uptake of plants, leading to better growth and yield.(Sinha et al, 2012)

2.5 Assessment of Super Gro and Boostract biofertilizers with other fertilizers:

Super Gro and Boos tract Bio Fertilizers are organic fertilizers that are believed to improve nutrient uptake by plants. However, how do they compare with other fertilizers, such as chemical fertilizers and other organic fertilizers? Chemical fertilizers are synthetic fertilizers that are usually rich in nitrogen, phosphorus, and potassium. They are popular among farmers and gardeners because they are easy to apply and provide plants with the necessary nutrients for growth. However, they can also have negative environmental effects, such as polluting water sources and harming beneficial microorganisms in the soil (Umar and Sani, 2017). Other organic fertilizers, such as compost, manure, and bone meal, are also widely used. These fertilizers contain organic matter that helps to improve soil structure and provide nutrients to plants. However, they may not have the same nutrient content as Super Gro and Boos tract Bio Fertilizers and they may also contain pathogens and weed seeds (Odedina et al, 2003). Super Gro and Boos tract Bio Fertilizers are two organic fertilizers that are believed to improve plant growth and yield by providing the necessary nutrients for plants to grow. Studies have shown that these fertilizers can improve the nutrient uptake of plants, leading to better growth and yield. While they may not be as popular as chemical fertilizers, they offer a natural and environmentally friendly alternative. They are also more targeted to fix the nutrient deficiencies of plants than other organic fertilizers Jat et al,( 2014)

2.6 Comparative effects of organic based fertilizer and mineral fertilizer on  dry matter yield of cowpea

The practices of involving multicropping system and reduced fallowing are commonly engaged by farmers in the developing countries. These practices often cause nutrient depletion and low organic matter in most soils due to lack of proper soil management Kosir et al, (2020). The use of mineral fertilizers as soil amendment has been widely accepted by farmers and is regarded to be a quick solution to soil fertility problems in the area. However, wide adoption of most fertilizer recommendations has been limited due to scarcity and/or high cost of product.  The use of organic materials as alternative source of fertilizer for maintenance of soil organic matter is now receiving attention in the developing countries (Uzoho and Uzoho, 2014). It is envisaged that locally available materials of plant and animal origin, by-products of agricultural activities be used or, where such materials are available in abundance, in situ recycling of organic wastes be done. Proper use of organic material as fertilizer improves both physical and chemical properties and as well as microbial activities of the soil Odedina et al, (2003). Organic materials such as farmyard manure, crop residues, etc, are bulky and supply low quantities of major plant nutrients. Nutrients release from the materials is also slow. Their efficiency, therefore, require to be improved through addition or supplementary application of some essential plant nutrients in the form of mineral fertilizer and/or agro minerals (Zewdinesh and Lisanework, 2016). Recycling of these organic wastes is therefore important for a sustainable agriculture Odedina et al, (2003). Also, Composting of organic materials reduces bulk, transportation and application costs, increases rate of nutrients release and enhances crop yield. Agbede, (2013), indicated significant yield increase when Compost was used on Korean soils low in organic matter.  Short- and long-term effects of organic manures have been demonstrated widely in India and China where cow dung is abundantly available for use as an organic source of plant nutrients (Agbede, 2013). In Nigeria, the importance of organic manuring in farming system has been highly emphasized and its effect as a source of lime and micronutrients under intensive agriculture has been demonstrated (Agbede, 2013). Micronutrients problems are well shown in some major soils in tropical Africa. The micronutrients are rarely supplied with the conventional mineral fertilizers except recently, in the late 90s, but they are very expensive.  Supplementation of organic manure with mineral fertilizer is highly necessary in meeting crop requirement of plant nutrients. This, however, involves extra costs of application, especially at top dressing. Production of mixed fertilizer materials (organic and mineral fertilizers) may be a complication at the farmers’ level. The present study was, therefore, aimed at evaluating, in the greenhouse, the effectiveness of organic based fertilizer (Compost fortified with mineral fertilizer) on cowpea performance (Agbede, 2013)

2.7. Integrated Impact of Organic and Inorganic Fertilizers on Growth, Yield of cowpea and Soil Properties

Increasing cowpea production is one of the most important goals for the Egyptian agricultural policy to face the human and animal demands. Sustainability of the agriculture production systems is the most crucial issue as our natural resources are continuingly being degraded. Furthermore, the possibility of mixing cowpea with wheat for bread making has also increased the demand of cowpea in Egypt. The increasing population and food demand has forced farmers to use high doses of chemical fertilizers. The unscientific use of fertilizers (nutrient imbalances, incorrect amount) is a serious threat to the sustainable agriculture production system Zuma et al,( 2016). The use of both organic and inorganic fertilizer by farmers has been reported to increase yield, sustain productivity and improved soil chemical properties (Oyedeji, 2016). Application of mineral fertilizer in combination with locally available organic fertilizer is important to maintain soil fertility that achieves balance nutrient supply in order to increase crop yield. It is one of the best practices for plant nutrient management to optimize social, economic, and environmental benefits of crop production. Integrated soil fertility management involving the judicious use of combinations of organic and inorganic resources is a feasible approach to overcome soil fertility constraints. Combined organic/ inorganic fertilization both enhanced carbon storage in soils and reduced emissions from nitrogen fertilizer use while contributing to high crop productivity in agriculture Ojeniyi et al., (2010). The use of inorganic fertilizers alone has not been helpful under intensive agriculture because it aggravates soil degradation. Maintaining and improving soil quality is crucial if agricultural productivity and environment quality are to be sustained for future generations. Intensive agriculture has had negative effects on the soil environment over the past decades (e.g. loss of soil organic matter, soil erosion and water pollution). Management methods that decrease requirements for agricultural chemicals are needed in order to avoid adverse environment impacts. Asadollahi et al (2013) and Abdelzaher et al. (2017) they observed that combined application of organic and inorganic fertilizer increased the growth and yield of cowpea than when any of the fertilizer was used alone. Tolessa and Friesen (2001) reported that cowpea growth and yield were significantly increased by farmyard manure (FYM) application enriched with chemical fertilizers. The role of organic fertilizers (compost) is improving soil organic matter, nitrogen content and phosphorus concentration. Furthermore decreasing soil pH, which result in increasing solubility of nutrients and nutrient availability to the plants, hence enhancement plant growth and development as well as gradually increase cowpea grain yield Ojeniyi et al., (2010). Biological fertilizers would play the key role in productivity and sustainability of soil and also protect the environment as eco-friendly and cost effective inputs for the farmers. Bio-fertilizer helps in increasing crop productivity by increasing nutrients availability uptake through solubilization, absorption, stimulation hormonal action or antibiosis and decomposition of organic residues (Agbede, 2013). Dauda et al (2008) reported that the high input cropping system was the most productive treatment but organic cropping system with biofertilizers was the most economical treatment with respect to increasing net profit

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

  3.0                                                       CHAPTER THREE

  3.1                                            MATERIALS AND METHODS

3.2 Site description

The experiment was conducted at the Teaching and Research Farm of the Department of Agricultural Technology of the Federal Polytechnic, Ado-Ekiti in June, 2023. The experiment was carried out to evaluate the potentials of different organic biofertilizers on performance of cowpea. The study area experiences rainfall and sunshine with an annual rainfall of about 2000 mm-3000 mm and a temperature of between 25⁰c to 30⁰c. This encourages fast growth of crops and other vegetables which cannot tolerate frost condition.

3.3 Experimental design and treatment.

The experiment was a 2×4 factorial combination arranged in a randomized complete block design

The following are the treatment and treatment combinations

Improved variety of cowpea (IT89KD-288) and an indigenous variety (Oloyin Brown)

Other treatments included;

1. Super Gro Biofertilizer (SPG) applied at 10ml per plot
2. Boostract Biofertilizer (BTB) applied at 10ml per plot

• Combination of (SPG + (BTB)

1. Control  (CLT)

There were 8 treatments replicated 4 times to make a total of 32 pots. Two seeds each of the tested cowpea varieties were planted on a seed bed measuring 2mx2m in a plot of 20mx10m. Planting was carried out in June, 2023 and weeding was done every fourth night while pest was controlled with the use of Cypermethrine insecticide with the use of a hand sprayer applied every fourth night for a period of 8 weeks. Treatments were applied at the rate of 10ml per plot a week after germination.

3.4 Growth and yield Parameters measured

Plant height: Plant height was estimated by measuring the distance from the soil surface to the tip of the main stem of the cowpea plant. This was done using a measuring tape or ruler.

Number of leaves: The number of leaves on the cowpea plant was counted manually, starting from the bottom of the plant and moving upwards. According to a study by Odedina, (2003), the number of leaves on cowpea plants was significantly influenced by different rates of organic biofertilizers in his study on legume crops.

Number of branches: The number of branches on the cowpea plant was counted manually. According to a study by Ndor et al. (2012), cowpea plants grown under different rates of organic fertilizers had significantly different numbers of branches.

Stem girth: Stem girth was measured using a wire or flexible tape. The tape is wrapped around the main stem of the cowpea plant, just above the soil surface. According to a study by Odedina,. (2003), stem girth was significantly higher in cowpea plants grown using different nutrient sources. Leaf area: Leaf area can be estimated using non-destructive methods such as digital image analysis. According to a study by Deksissa et al, (2008), leaf area index was significantly affected by different planting densities and sowing dates in cowpea plants.

Days to first flowering: Days to first flowering was estimated by visually inspecting the cowpea plants for the appearance of the first flower and counting the days to first flowering from the time of planting to the time first flower appeared. According to a study by Odedina. (2003), days to first flowering was significantly influenced by different manures in cowpea plants.

Days to first podding: Days to first podding was estimated by visually inspecting the cowpea plants for the appearance of the first pod. According to a study by Ojeniyi et al. (2010), days to first podding was significantly influenced by different nutrient sources on legume crops..

 Pod length: Pod length was measured using a ruler or a digital caliper. According to a study by Singh et al. (2016), pod length was significantly affected by different levels of nitrogen and phosphorus fertilizers in legume plants.

Number of seed per pod: The number of seeds per pod was counted manually, after the pods have matured and dried. According to a study by Mohammed et al. (2018), the number of seeds per pod was significantly influenced by different planting densities and fertilizer treatments in cowpea plants.

Number of pods per plant: The number of pods per plant was counted manually, after the pods have matured and dried. According to a study by Singh et al. (2016), the number of pods per plant was significantly affected by different levels of nitrogen and phosphorus fertilizers in cowpea plants.

Pod weight: Pod weight was measured using a digital scale, after the pods have matured and dried. According to a study by Omoigui et al. (2011), pod weight was significantly affected by irrigation and fertilizer treatments in cowpea plants.

Pod yield: Pod yield was estimated by weighing all the mature and dried pods harvested from each cowpea plant. According to a study by Farinde et al. (2018), pod yield was significantly influenced by different fertilizer treatments and sowing dates.

3.5 Characteristics of Bio fertilizers used for the experiment

The bioactive compounds present in Boos tract are Anti-Microbial so they deter pest and diseases.

They contain nutrients which enhance rapid and stable growth.

Biofertilizers improve the soil texture, allowing it to hold water longer.

They increase the bacterial and fungal activity in the soil.

They boost both nutrient efficiency and organic matter content in the soil.

They nurture the soil with organic matter that reduces dependency on chemical inputs.

They restore and maintain soil fertility to nurture plant growth.

All data collected were subjected to analysis of variance (ANOVA) while treatment means were separated using the Duncan Multiple Range Test (DMRT) at 5 % level of probability. Standard Deviation and Standard Error were also employed to determine the level of accuracy and deviation from the Mean.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                                                          CHAPTER FOUR

4.0                                           RESULT AND DISCUSSION

Table 1: Effect of organic biofertilizers on plant height of two cowpea varieties

Treatments	Varieties	2WAP		4WAP		6WAP		8WAP
SPG	IT89KD-288 Oloyin Brown	10.3a 10.7a		14.7b 13.6b		18.0b 14.6d		26.6b 22.7c
BTB	IT89KD-288 Oloyin Brown	9.7b 8.9b		12.8c 10.9d		16.2c 14.8d		24.4c 19.9d
SPG+BTB	IT89KD-288	12.0a		16.5a		21.4a		29.8a
CLT	Oloyin Brown   IT89KD-288	11.5a   8.0b		14.4b   11.0d		18.7b   14.9d		23.6c   17.3e
Mean	Oloyin Brown	7.9b 10.52		10.8d 13.87		13.0d 16.86		16..8e 23.10
SD		1.47		2.45		2.94		4.79
SE±		0.52		0.86		1.04		1.69
CV (%)		0.14		0.18		0.17		0.21

Means carrying the same superscript along the same columns are not significantly different at 5% probability level.SD-Standard Deviation.CV-Coefficient of Variability.WAP=Weeks after planting. SPG-Super Gro-Bio fertilizer.BTB-Boostract bio fertilizer. CLT-Control

The result of organic bio-fertilizer effect on plant height of two cowpea varieties is presented in Table 1. The result shows that at 8WAP, highest plant height was significantly recorded for combination of Super Gro + Boostract organic bio-fertilizer for IT98KD-288 (29.8cm). This was closely followed by application of Super Gro alone for IT98KD-288 (26.6cm) while the least was recorded for the control for both tested cowpea varieties. The result shows that the application of organic bio-fertilizer enhanced plant height of cowpea at different growth stage of growth while the indigenous variety was inferior in plant height development when compared to the improved variety with superior character.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 2: Effect of organic biofertilizers on number of leaves of two cowpea varieties

Treatments	Varieties	2WAP		4WAP		6WAP		8WAP
SPG	IT89KD-288 Oloyin Brown	7.3a 7.0a		18.7b 14.6c		38.0c 34.6d		62.6c 55.7d
BTB	IT89KD-288 Oloyin Brown	7.7a 6.9a		17.7b 15.9c		32.2e 27.9f		54.4d 50.9e
SPG+BTB	IT89KD-288	8.0a		21.5a		44.4a		70.8a
CLT	Oloyin Brown   IT89KD-288	7.5a   6.7a		18.4b   13.6d		40.7b   29.6f		65.6b   48.0e
Mean	Oloyin Brown	6.3a 7.46		11.8d  15.85		21.4g 33.13		32.5f 56.37
SD		0.58		2.45		7.27		8.95
SE±		0.21		8.65		2.57		3.17
CV (%)		0.08		1.04		0.22		0.16

Means carrying the same superscript along the same columns are not significantly different at 5% probability level.SD-Standard Deviation.CV-Coefficient of Variability. WAP=Weeks after planting. SPG-Super Gro-Bio fertilizer.BTB-Boostract bio fertilizer. CLT-Control

The result of organic bio-fertilizer effect on number of leaves of two cowpea varieties is presented in Table 2. The result shows that there was no significant difference in the number of leaves at 2WAP for all the tested cowpea varieties based on the treatments imposed. However, at 8WAP, significantly highest value was recorded for the combination of Super Gro + Boostract organic bio-fertilizer for IT98KD-288 (70.8). This was closely followed by Oloyin Brown at the same combination (65.6) while Super Gro alone for IT98KD-288 followed (62.6) with the least recorded for the control for both tested cowpea varieties. The result shows that the application of organic bio-fertilizer enhanced number of leaves of cowpea at different growth stage of growth while the indigenous variety was inferior in leaf number when compared to the improved variety with superior character.

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 3: Effect of organic biofertilizers on number of branches of two cowpea varieties

Treatments	Varieties	2WAP		4WAP		6WAP		8WAP
SPG	IT89KD-288 Oloyin Brown	2.3a 2.7a		4.7a 3.6a		8.0ab 6.6b		10.6ab 9.7b
BTB	IT89KD-288 Oloyin Brown	2.7a		4.7a 4.0a		9.2a 8.9ab		10.4ab 9.9b
SPG+BTB	IT89KD-288	2.0a		4.5a		10.4a		12.9a
CLT	Oloyin Brown   IT89KD-288	2.5a   2.9a		4.4a   3.2a		8.7ab   8.1ab		11.8a   10.0ab
Mean	Oloyin Brown	2.5a 2.25		3.1a 4.22		6.0b 8.50		9.5b 10.65
SD		0.29		0.57		1.04		1.19
SE±		0.10		0.20		0.36		0.42
CV (%)		0.11		0.14		0.12		0.11

Means carrying the same superscript along the same columns are not significantly different at 5% probability level.SD-Standard Deviation.CV-Coefficient of Variability. WAP=Weeks after planting. SPG-Super Gro-Bio fertilizer.BTB-Boostract bio fertilizer. CLT-Control

The result of organic bio-fertilizer effect on number f branches of two cowpea varieties is presented in Table 3. The result shows that there was no significant difference in the number of branches at 2WAP and 4WAP for all the tested cowpea varieties based on the treatments imposed. However, at 8WAP, significantly highest value was recorded for the combination of Super Gro + Boostract organic bio-fertilizer for IT98KD-288 (12.9). This was closely followed by Oloyin Brown at the same combination (11.8) while Super Gro alone for IT98KD-288 followed (10.6) with the least recorded for the control for both tested cowpea varieties. The result shows that the application of organic bio-fertilizer enhanced number of branches of cowpea at different growth stage of growth while the indigenous variety was inferior in leaf number when compared to the improved variety with superior character.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 4: Effect of organic biofertilizers on stem girth of two cowpea varieties

Treatments	Varieties	2WAP		4WAP		6WAP		8WAP
SPG	IT89KD-288 Oloyin Brown	1.3a 1.2a		2.7a 2.6a		3.7a 3.6a		3.9a 3.8a
BTB	IT89KD-288 Oloyin Brown	1.9a 1.8a		2.7a 2.6a		3.2a 3.5a		3.7a 3.8a
SPG+BTB	IT89KD-288	1.9a		2.6a		3.5a		3.9a
CLT	Oloyin Brown IT89KD-288	1.6a 1.6a		2.9a 2.3a		3.9a 3.0a		4.0a 3.5a
Mean	Oloyin Brown	1.4a 1.62		2.2a 2.60		2.8a 3.48		3.8a 3.82
SD		0.34		0.23		0.33		0.13
SE±		0.19		0.08		0.12		0.05
CV (%)		0.21		0.09		0.09		0.03

Means carrying the same superscript along the same columns are not significantly different at 5% probability level.SD-Standard Deviation.CV-Coefficient of Variability. WAP=Weeks after planting. SPG-Super Gro-Bio fertilizer.BTB-Boostract bio fertilizer. CLT-Control The result of organic bio-fertilizer effect on stem girth of two cowpea varieties is presented in Table 4. The result shows that there was no significant difference in the stem girth of the two tested cowpea varieties for all the treatments imposed throughout the growth stage of cowpea.

 

Table 5: Effect of organic biofertilizers on leaf area development of two cowpea varieties

Treatments	Varieties	2WAP		4WAP		6WAP		8WAP
SPG	IT89KD-288 Oloyin Brown	10.3a 10.7a		14.7a 13.6a		18.0a 14.6ab		22.6b 18.7d
BTB	IT89KD-288 Oloyin Brown	9.7ab 8.0ab		11.7ab 10.9ab		14.2ab 12.5ab		18.4d 16.9e
SPG+BTB	IT89KD-288	11.0a		13.5a		17.4a		25.8a
CLT	Oloyin Brown   IT89KD-288	10.5a   8.0ab		12.4ab   10.7ab		14.7ab   13.5ab		21.6c   15.9e
Mean	Oloyin Brown	9.3ab 9.62		15.8a 12.50		15.0ab 15.12		19.0d 20.87
SD		1.31		1.72		1.67		3.70
SE±		0.46		0.61		0.59		1.31
CV (%)		0.14		0.13		0.11		0.17

Means carrying the same superscript along the same columns are not significantly different at 5% probability level.SD-Standard Deviation.CV-Coefficient of Variability. WAP=Weeks after planting. SPG-Super Gro-Bio fertilizer.BTB-Boostract bio fertilizer. CLT-Control

The result of organic bio-fertilizer effect on leave area development of two cowpea varieties is presented in Table 5. The result shows that there was no significant difference in the number of branches at 2WAP for all the tested cowpea varieties based on the treatments imposed. However, at 8WAP, significantly highest value was recorded for the combination of Super Gro + Boostract organic bio-fertilizer for IT98KD-288 (25.8cm²). This was closely followed by IT98KD-288 for Super Gro alone (22.6cm²) with the least recorded for the control for both tested cowpea varieties. The result shows that the application of organic bio-fertilizer enhanced number leaf area development of cowpea at different growth stage of growth while the indigenous variety was inferior in leaf number when compared to the improved variety with superior character.

Table 6. Effect of biofertilizers on yield and yield characters of two cowpea varieties

Treatments	Varieties	Days to first flowering	Days to first podding	Number of pods/plant	Number of seed/pod	Pod length (cm)	Shoot biomass (g)	Pod yield (kg/ha)
SPG	IT89KD-288	35.0c	45.0c	11.9b	12.0a	15.9c	147.0b	417.8c
	Oloyin Brown	40.0b	50.0b	8.0d	10.9b	13.0d	284,9a	324.7d
BTB	IT89KD-288	35.0c	45.0d	12.6b	12.7a	16.6c	157.5b	406.6c
	Oloyin Brown	40.0b	50.0b	10.4c	9.4b	14.3d	289.3a	312.4d
SPG+BTB	IT89KD-288	35.0c	45.0c	14.2a	13.6a	22.2a	149.1b	509.6a
	Oloyin Brown	40.0b	50.0b	12.5b	11.8a	18.7b	290.4a	401.0b
CTL	IT89KD-288	40.0b	50.0b	8.3d	8.0b	13.5d	146.6b	213.8e
	Oloyin Brown	45.0a	55.0a	7.1d	6.3c	11.8e	279.8a	201.3e
Mean		36.25	48.12	10.87	10.88	15.12	247.13	362.37
SD		15.59	2.50	2.39	2.28	3.62	65.99	98.15
SE±		5.52	0.88	0.85	0.81	1.28	23.36	34.76
CV (%)		0.43	0.05	0.22	0.21	0.23	0.27	0.27

Means carrying the same superscript along the same columns are not significantly different at 5% probability level.SD-Standard Deviation.CV-Coefficient of Variability

The effect of biofertilizers on yield and yield characters of cowpea is presented in Table 6.The result shows that days to first flowering were significantly shorter with application of biofertilizers while the improved cowpea variety gave superior attributes over the indigenous cowpea variety. Similarly, days to first poddding were significantly shorter with application of biofertilizers over the control.IT98K-288 had significantly higher value for number of pod (14.2), number of seed (13.6), pod length (22.2cm) and pod yield (509.6kg/ha) over other treatment. This was closely followed by application with Super Gro alone with the least value recorded for the control.

 

 

 

 

 

Table 7: Physical and chemical properties of the soil at experimental site

Properties	Values
Ph	5.95
Total N (%)	0.38
Available P (mg/kg)	16.10
Exchangeable cations (Cmol.kg-1)
Ca2+	5.40
Mg2+	2.50
K+	1.07
Na2+	0.38
Organic Carbon (%)	1.80
Organic matter (%)	0.59
H+	0.20
CEC	2.96
Particle size distribution
Sand	82.30
Silt	10.50
Clay	7.20
Texture	Sandy loam
Bulk density (g/cm3)	1.32

From the experiment, there is significant difference in most of the measured growth and yield parameters of the two cowpea varieties under application of Super Gro bio-Fertilizer. This agreed to the fact that foliar fertilization not only improves plant growth traits, crop yields and nutrient uptake by crops (Dekissa et 2018), but also enhances nutrient use efficiency of crops (Fageria et al., 2009). Hence benefits of foliar fertilizers under study might be related to their multi-nutrient contents, which upon absorption by the leaf tissues improved the growth traits of cowpea plants and resultantly increased yield. Application of biofertilizers facilitates timely translocation of deficient nutrients to plant system through leaf tissues (Idem et 2012). Alkaff and Hassan (2012), reported improved growth and yield traits of cowpea in relation to foliar fertilization. Early flowering and podding was noted by the foliar application of micronutrients was observed in fruit vegetables. (Mishra et al., 2003). Biofertilizers is 100% new generation organic liquid fertilizer that is made from poultry droppings, sea bird guano and organic matter with absolutely no chemicals was added to it for the improvement of agricultural development. It’s 100% safe to use on any vegetables and of course the rest of your garden. Biofertilizers can be applied to any plant, tree, vegetable and even grass that required fertilization. Organic biofertilizers assists more water to reach the roots of the plant and stays there, optimizing plant growth in less time. It’s a source of fertilizer to protect crops for healthy growth of Agricultural and farm products. It’s also a naturally wetting agents, penetrable, spreader and sticker that have no chemical. It increases the production of food and cash crops. Generally, results of the study conform to the findings of Idem et al., 2012 that crop response to fertilizer application is affected by nutrient reserve in the soil. According to them, crops response to fertilizer application in soil with very low nutrient content than soil with high nutrient reserve. Organic fertilizer apart from releasing nutrient element to the soil has also shown to improve other soil chemicals physical properties which enhance crop growth and development (Ogbonna, 2018; Dauda et al., 2018 and Uko et al., 2009). The growth parameters were greatly influenced by the application of the different levels of Super Gro liquid organic fertilizers, since fluted pumpkin is a vegetable which made its production to require nitrogenous fertilizers for its optimum growth. These findings are in accordance with some literature citation on the report of Adebisi et al (2011) that organic fertilizers apart from releasing nutrient elements to the soil has also showed to improve other soil chemical properties which enhanced  crop growth and development

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 5.0                                                CHAPTER FIVE

                             CONCLUSION AND RECOMMENDATIONS:

5.1. Conclusion

The study concludes that the use of organic biofertilizers can improve the growth, yield, and quality of cowpea varieties. Combinations of Super Gro and Boos tract biofertilizers provided better results than their individual application. Improved IT89KD-288 performed better than Oloyin brown in terms of growth and yield.

5.2. Recommendation

Therefore, the study recommends the use of biofertilizers as a sustainable alternative to synthetic fertilizers in cowpea production. Further studies are required to investigate the effects of biofertilizers on cereal crops. The study also recommends the combination of Super Gro with Boostract organic Biofertilizer as a good alternative to synthetic fertilizer to enhance crop growth and yield.

 

 

 

 

 

 

 

 

 

 

 

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