GROWTH, YIELD AND NUTRIENT UPTAKE OF CORN (Zea mays L.

TREATED WITH MYKOPLUS APPLIED WITH

DIFFERENT FERTILIZER MATERIAL

JENNIFER MACARAIG MENDOZA

Southern Luzon State University

Tiaong Campus

2021
 Chapter 1

INTRODUCTION

Grain crops are annuals and labeled as the most important group of cultivated

plants as they serve as basic food products for humans, feed for animals and used as raw

materials in different industries. One of the grain crops is corn or maize, scientifically

known as Zea mays L. that belongs to the grass family Gramineae or Poaceae. Corn is

grown all over the globe and out of seven continents in the world, Antarctica is the only

exception. It is a tall-growing plant with normally about 20 horizontal leaves standing

alternately along the main culm which is commonly composed of 20 internodes, and it

produces cob that usually consists of 800 kernels that are arranged in 16 rows (Moyer, K.,

2018). As the male flowers are located above female organs, corn is usually pollinated by

wind or by gravity, (Bertin, 2015). Corn provides necessary calories, various vitamins,

minerals, antioxidants as well as it is high in fiber that is good for the body (BPSD.org,

2020).

According to PSA (2019) as of August 1, 2019, Philippines’s corn production in

the total of 2.76 million metric tons is higher by 25.3 percent from the previous year’s

level of 2.20 million metric tons. The top producer of corn in the country remained to be

Cagayan Valley designated as Region II; whereas, Central Luzon, designated as Region

III ranked as sixth in terms of corn production which contributed 5.4 percent to the total

volume of corn production in the Philippines. As stated by Corpuz (2020), Philippines’s

corn production is expected to increase from 100,000 tons to 8.2 million tons in market

years 20/21, due to rising food demands and shifting away from sugarcane, rice as well as

cassava to corn production.

 Plants need necessary elements called essential plant nutrients to achieve its

growth and complete its life cycle. As for corn plants, it requires large amounts of

nitrogen (N), phosphorus (P) and potassium (K) to grow (OGTR, 2008). Though plants

and soil need so many more nutrients other than these three (N, P, K), research shows

that these primary nutrients are the one needed to produce higher yields. Muchow (1998)

together with Subedi, K.D. and Ma, B.L. (2009) specified that nitrogen is one of the most

important plant nutrients as it is required for the production of proteins and chlorophyll,

promotes rapid growth, maintenance of photosynthetic efficiency, leaf area development,

and ultimately dry matter production. Although P is not present as large quantities as N in

the plant tissues, it is involved in many crucial metabolic functions that occur in plant cell

(Johnston and Dowbenko, 2004; Subedi, K.D. and Ma, B.L., 2009), and according to

Savoy, H. (2012) phosphorus stimulates early root growth, hastens maturity, stimulates

blooming and aids seed formation. Moreover, potassium is required for many purposes in

the plants such as in photosynthesis, protein synthesis, disease resistance, carbohydrate

translocation and drought tolerance in plants (Subedi, K.D. and Ma, B.L.,2009).

To gain these nutrients, there are certain inputs that farmers use and one of them

is biological fertilizer or simply biofertilizer. Biofertilizers according to Kumar, R., et al.,

(2017) and DOST-PCAARRD (2015) are natural fertilizers which are living microbial

inoculants of bacteria, algae, fungi alone or in combination which enhances the growth

and yield of crops as well as the availability of nutrients to the plants and help remediate

the problem in soil fertility. Kumar, R., et al., (2017) stated that the long-term use of bio-

fertilizers is more efficient, economical, productive, eco-friendly, as well as it is

affordable to marginal and small farmers over chemical fertilizers. MykoPlus is one of

the common biofertilizers that farmers use. 

MykoPlus is a multi-strain and multi-species bio-fertilizer which contains

mycorrhizal fungi; beneficial bacteria that include nitrogen fixers, phosphorus

solubilizers, growth hormone secretors, and others (DOST-PCAARD, 2015). Note that

the creation of a diverse population of the beneficial microorganisms is the most

important effect of MykoPlus. To make the soil ideal for crop production, these

microorganisms work together to improve the physical, biological and chemical

properties of the soil. 

Another input that farmers use to increase the productivity of crop production is

the fertilizers. Savoy (2012) suggested that fertilizers are sold in three forms namely

solid, liquid and gaseous form (anhydrous ammonia); and it is derived from a wide

variety of natural and manufactured materials. Note that these materials are designed for

use or claimed to have value in promoting plant growth or increasing plant-available

nutrient levels in soils. There are two types of fertilizers categorized as organic and

inorganic.

As stated by Savoy (2012) organic fertilizers usually mean that the nutrients

contained in the product are derived solely from living organisms that eventually die and

decompose. One of the examples of organic fertilizers is animal manures, which are

usually from cow, swine and poultry are probably the most commonly available organic

material used for their fertilizer value and is essentially a complete or mixed fertilizer,

meaning it contains the primary nutrients (N, P, K) (Savoy, 2012) and (Subedi, K.D. and

Ma, B.L. 2009).

 On the other hand, inorganic fertilizers are generally referred to as those fertilizers

that are artificial or synthetic as the nutrients contained in it have been manufactured or

synthesized (Delp, R., 2019). Furthermore, in the study of Mahmood, F. et. al, (2017)

showed significant improvement in the growth and yield of maize by applying fertilizer

together with organic manures. 

Hence, the focus of this study is about assessing the growth, yield, nutrient

uptake, application of fertilizer materials, and biofertilizer specifically, Mykoplus in the

corn plant. 

Background of the Study 

The researcher is interested in pursuing this study which is about improving the

growth, yield and nutrient uptake of corn by using different fertilizer materials and

biofertilizer. Based on the data gathered by the researcher, Mykoplus applied in corn

helps the roots of the plant to obtain more nutrients and water from the soil, thereby

enhancing crop growth which can result in higher yield. The researcher combined the use

of different fertilizer materials together with the Mykoplus for the reason that both of

them have significant effects when applied on the corn plant. Therefore, there is a need to

assess the capability of Mykoplus to increase the nutrient uptake of corn that will lead to

better growth and yield in different fertilizer materials.

Objectives 

  Generally, this study aims to assess the growth, yield, and nutrient uptake of corn

treated with MykoPlus applied with different fertilizer materials.

Specifically, this study aims;

 1. To determine the effects of MykoPlus and different fertilizer materials in the

growth, yield, and nutrient uptake of corn in terms of:

1.1. Growth Parameters

1.1.1. Number of Days from Sowing to Emergence

1.1.2. Number of Days from Emergence to Flowering

1.1.3. Number of Days from Flowering to Harvesting

1.1.4. Weekly Plant Height

1.1.5. Weekly Number of Leaves

1.1.6. Length of Roots

1.1.7. Fresh Biomass

1.1.8. Dry Mass

1.2. Yield Components

1.2.1. Length of Corn Ear

1.2.2. Weight of Corn Ear

1.2.3. Diameter of Corn Ear

1.2.4. Number of Corn Ear per Harvest Area

1.2.5. Weight of Harvested Corn Ear per Harvest Area

1.2.6. Computed Yield per Hectare

1.2.7. Number of Marketable Corn Ear

1.2.8. Number of Non-Marketable Corn Ear

1.3. Nutrient Uptake

1.3.1. P in plant tissue

1.3.2. K in plant tissue

 1.4. Agronomic Parameters

1.4.1. Harvest Index

1.5. Pest Incidence and Damages

1.6. Cost and Return

1.6.1. Gross Profit

1.6.2. Return of Investment

2. To determine if there is significant difference on the effect of MykoPlus and

different fertilizer material in the growth, yield and nutrient uptake of corn in terms of:

2.1. Growth Parameters

2.2. Yield Parameters

2.3. Nutrient Uptake Parameters

2.4. Agronomic Parameters

2.5. Pest Incidence and Damages

2.6. Cost and Return

3. To determine which fertilizer material best suited in improving the growth,

yield and nutrient uptake of corn in terms of:

3.1. Growth Parameters

3.2. Yield Parameters

3.3. Nutrient Uptake Parameters

3.4. Agronomic Parameters

3.5. Pest Incidence and Damages

3.6. Cost and Return

 4. To find out if there will be interaction effect between MykoPlus and fertilizer

material in corn production in terms of:

4.1. Growth Parameters

4.2. Yield Parameters

4.3. Nutrient Uptake Parameters

4.4. Agronomic Parameters

4.5. Pest Incidence and Damages

4.6. Cost and Return

5. To determine which MykoPlus and fertilizer material combination will be most

economical to use in improving corn production through the analysis of:

5.1. Cost and Return

5.1.1. Gross Profit

5.1.2. Return of Investment

Conceptual Framework

Figure 1 shows the paradigm of the conceptual framework of the study. The box

on the left indicates the independent variables which includes the Inoculant (Factor A)

such as MykoPlus (M1) and without MykoPlus (M2) and the fertilizer (Factor B) such as

chicken manure (F1), inorganic (F2), their combination (F3), and without fertilizer (F4).

The effect of which will be measured and compared with the effects of other treatments

as presented on the second box which contain the dependent variables which were

divided growth, yield, nutrient uptake, agronomic parameters of the crop, pest incidence

and damages, and lastly the cost and return.

 Independent Variable Dependent Variable

Growth Parameters
1.1. Number of Days from Sowing to
Emergence
1.2. Number of Days from Emergence to
Flowering
1..3. Number of Days from Flowering to
Harvesting
1.4. Weekly Plant Height
1.5. Weekly Number of Leaves
1.6. Length of Roots
FACTOR A (M)- Inoculant 1.7. Fresh Biomass
1.8. Dry Mass
M1- MykoPlus
M2- Without MykoPlus 2. Yield Components
2.1. Length of Corn Ear
  2.2. Weight of ear
FACTOR B (F)- FERTILIZER 2.3. Diameter of ear
MATERIALS 2.4. Number of Corn ear per Harvest Area
2.5. Weight of Harvest per Harvest Area
F1- Chicken Manure 2.6. Computed Yield per Hectare
F2- Inorganic Fertilizer 2.7. Number of Marketable Corn Ear
2.8. Number of Non-Marketable Corn Ear
F3- Combination
3. Nutrient Uptake
F4- Without fertilizer
3.1. P in plant tissue
3.2. K in plant tissue

4. Agronomic Parameters
4.1. Harvest Index

5. Pest Incidence and Damages

6. Cost and Return

6.1. Gross Profit
6.2. Return of Investment

Figure SEQ Figure \* ARABIC 1. Paradigm of the relationship between independent and
dependent variables
Hypotheses 

 The following null and alternative hypotheses were tested in this study:

H0: There was no significant difference on the effects of biofertilizer and fertilizer

materials used in the study in terms of: growth parameters of corn, yield components of

corn, nutrient uptake of corn, agronomic parameter, pest incidence and damages, and cost

and return.

H0: There was no significant interaction between the biofertilizer and fertilizer

materials used in the study in terms of: growth parameters of corn, yield components of

corn, nutrient uptake of corn, agronomic parameter, pest incidence, and damages, and

cost and return.

H1: There was a significant difference on the effects of biofertilizer and fertilizer

materials used in the study in terms of: growth parameters of corn, yield components of

corn, nutrient uptake of corn, agronomic parameter, pest incidence and damages, and cost

and return.

H1: There was significant interaction between the biofertilizer and fertilizer

materials used in the study in terms of: growth parameters of corn, yield components of

corn, nutrient uptake of corn, agronomic parameter, pest incidence and damages, and cost

and return.

Significance of the Study 

The result of this study would significance to the following:

Farmers, the primary beneficiaries of this study as they are the one who is really

engaged in this field. The outcome of this study would provide additional knowledge on
corn production, fertilizer and MykoPlus inoculation to be used in order to improve the

production of corn.

Future researchers and students, for the result of this study would serve as

reliable reference for future study particularly in using biofertilizer and different fertilizer

materials in corn production.

Academicians, professors, instructors and teachers for the result of this study

to give them additional information that can be extended to their target beneficiaries for

corn production.

Community, for the result of this study would be used as basis and reference in

conducting projects to upgrade their data in producing corn.

Department of Agriculture, for the empirical data or information, taken from

this study would be used as bases in formulating programs and projects to support RA

10068 the Organic Agriculture Act, and RA 9003, the Ecological Solid Waste

Management. It can also become the basis or source of information regarding corn

production inoculated with MykoPlus and applied with different fertilizer materials.

Scope and Limitation of the Study

 This study is focused on the assessment of growth, yield and nutrient uptake of

corn, inoculation and fertilizer materials on corn. The study was limited only to the

effects of different fertilizer materials that were used such as biofertilizer, specifically

MykoPlus, chicken manure, triple 14 and urea to growth, yield, and nutrient uptake in

corn. This study was conducted at Southern Luzon State University- Tiaong Campus

located at Brgy. Lagalag, Tiaong, Quezon in May- August 2021.

Definition of Terms

The following terms were defined operationally to fully understand the study:

Agronomic parameters of corn such as growth, yield, harvest index and nutrient

efficiency were collected and serve as important data for the prediction of crop growth.

Computed yield per hectare is measured by dividing the total yield of corn in kg

per 3 m2 harvest area then multiplied by 10,000m2. The formula to be used is shown

Total Yield (kg)

___________________
Computed Yield per Hectare= X 10,000m2
Harvest Area

below:

  Cost and Return is important as it serves as measurement and evidence whether

the production is successful or not based on the computed net income. The cost and

return of plants were estimated based on the prevailing market price of corn in the area.

Fertilizer is any material produced naturally or synthetically that is applied to soil

or plant tissues to supply one or more plant nutrients essential to plant growth. In this

study organic fertilizer that was used is chicken manure while inorganic fertilizers are

triple 14 and urea.

Growth parameters in this study include the number of days from planting to

emergence, to flowering, and to harvesting, weekly plant height, weekly number of

leaves, fresh biomass, and dry mass.

Inoculation can be described as the process of adding effective bacteria to the

seed of the plant before the actual planting. The goal of inoculation is to ensure that

enough of the right type of bacteria are present in the soil.

 Marketable corn condition has its characteristics such as good kernels, complete

grains in the kernel rows, no discoloration of grains, and no sign of damage by insect or

mechanical.

MykoPlus is a biological fertilizer (Biofertilizer) that was applied into the seeds

before planting to enhance the crop's ability to take in nutrients from the soil.

Non-marketable corn condition has characteristics that may not be liked by the

consumers such as incomplete kernels, discoloration and damage on ears by the insect or

mechanical.

Nutrients help in survival and growth of corn plants such as phosphorus and

potassium which are classified as the primary nutrients necessary for plants.

Nutrient uptake by a crop refers to the total amount of the nutrients such as

phosphorus and potassium obtained from the materials applied in the crop that was

analyzed in the tissue of corn leaves.

Slurry method is the most common practice of applying biofertilizers. In this

method, the biofertilizers are mixed with liquid. The slurry is then poured over the seeds

spread on and mixed properly in a way that a thin layer is formed around the seeds. The

treated seeds should be dried in the shade overnight and then they should be used. 

Yield Components in this study include the number of corn ear per plant, length of

ear, weight of corn per 3 m2 harvest area, computed yield per hectare, number of

marketable and non-marketable corn.

 CHAPTER 2

REVIEW OF RELATED LITERATURE

To fully understand this study, the researcher reviewed several literatures, studies,

and readings related on this problem and presented as follows:

Corn Production in the Philippines

According to Gerpacio R., et al. (2004) corn is second to rice as the most

important crop in the Philippines. Corn also serves as a major source of livelihood for

one-third of Filipino farmers or 1.8 million depending on it. People in rural areas

substitute white corn for rice in periods of shortage. Yellow corn is the primary source of

feed for the animal industry as well as it is increasingly used by the manufacturing

sector. 

After an almost constant increase in productivity since 2003, maize production in

2014 reached 7, 770 kmetric tons on 2.61 million hectares (Bureau of Agricultural

Statistics, 2008, 2011; Gerpacio, et al. 2004; Statistics Authority, 2015). The majority of

this rising production of maize is devoted to feeding cattle or poultry for around 60

percent, while 40 percent is used for domestic consumption. (Bureau of Agricultural

Research, 2011). The study conducted by Delos Reyes J. A. and Quicoy, C.B. (2014) in

the region of Isabela, shows that the most important factors influencing the productivity

of maize farms were human labor, seeds, and fertilizer costs. In addition, the number one

production-related issue listed by the farmer-respondents was the availability of capital.

Cultivation of corn in the Philippines is dependent on an area's landscape and

topography. As of 2018, the production increased by 163 thousand metric tons

contributed by the Cagayan Valley. CAR, ARMM, and Caraga followed, with a total rise

of 42 thousand metric tons (PSA, 2019). The output volume of maize in the Philippines

was nearly eight million metric tons in 2019, higher than the amount of eight million

metric tons produced in the previous year. (Sanchez, M, 2020). Furthermore, in 2020, the

production of maize in the Philippines was 8,200 thousand tons which grew from 2,013
thousand tons in 1971, increasing at an annual average rate of 3.36 percent (World Data

Atlas, 2021).

For the fourth quarter of 2019, Quezon Province is the top corn producer in

CALABARZON according to PSA (2020). Furthermore, Quezon produced 28,055 metric

tons of corn and continues to remain as the top maize producer in the CALABARZON

region accounts for 62.6% of the region's total maize output of 44,796 metric tons in

production.

For proper growth and high yield of corn, it requires an adequate supply of

nutrients primarily the nitrogen, phosphorus, and potassium, by which can be obtained in

applied farm inputs in the soil. Manures and fertilizers are the alternatives used in

agriculture for this purpose. One of the key concerns is the management of nitrogen (N)

in the maize production system, because it is the most important and primary nutrient for

crop growth and development (Blumenthal, J. et al., 2008). Phosphorus (P) is one of the

main plant nutrients which is essential for plant growth and development (Viruel et al.,

2014) as well as in cell division and development of new tissue (Hameeda et al., 2008).

Potassium (K) is an essential plant macronutrient and plays an important role in many

physiological processes vital to plant nutrient and water uptake, nutrient transport, and

growth, especially under adverse conditions (Pettigrew, W.T., 2008 and Zörb, C.,

Senbayram, M., Peiter, E., 2014).

Biofertilizer

Bio-fertilizers or microbial inoculants are carrier-based ready-to-use live bacteria

or fungal formulations that help to mobilize different nutrients via their biological activity
when applied to plants, soil, or composting pits (Rana et al., 2013). Bio-fertilizers

according to Mohammadi and Sohrabi (2012) is a preparation containing live cells of

effective nitrogen fixer and phosphate solubilizer strains added to seeds and soil or

composting areas with the goal of raising the amount of such microorganisms, also to

increase the degree of nutrient availability in a form that can be assimilated by plants, and

to accelerate certain microbial processes.

According to Zaman et al., (2008), nitrogen fixing bacteria take up nitrogen gas

from the atmosphere by using enzymes then fix the nitrogen into bacterial biomass by

using sugars obtained from the plants. Khan et al. (2006) stated that nitrogen-fixing

organisms either applied alone or combined with phosphorus solubilizing

microorganisms, which is also one of the components of bio-fertilizer, not only provide

nitrogen to the plants, but also improve the nitrogen status of soil.

With the assistance of phosphate solubilizing bacteria, bio-fertilizers increase the

absorption of plants with phosphorus (Figueiredo et al., 2010). Through acidification,

chelation, exchange reactions and production of organic acids, the rhizobacteria such as

Phosphate solubilizing bacteria convert insoluble phosphates into soluble forms available

for plants (Rodríguez and Fraga 1999). In addition, it is concluded that the microbes

involved in the solubilization of phosphate will increase plant growth by improving the

efficiency of biological fixation of nitrogen, accelerating the availability of other trace

elements and generating phyto-hormones (Khan et al., 2006).

According to Kumar, R., et al. (2017), by fixing atmospheric di-nitrogen,

mobilizing fixed macro and micro nutrients in the soil into forms available to plants,

biofertilizers as important components of organic farming play a vital role in sustaining

long-term soil fertility and sustainability. In addition, bio-fertilizers increase crop yield

by 20-30 percent, replacing chemical nitrogen and phosphorus by 25 percent and

stimulating growth, according to Karanukaran et al. (2014). Accordingly, the need for

biofertilizer use occurs mainly for two reasons. Firstly, because increased fertilizer use

contributes to increased production of crops, secondly, because increased chemical

fertilizer use leads to soil texture damage and raises other environmental problems.

Moreover, in the study of Farahvash F. et. al, (2012), which used biofertilizers in corn as

a source of natural growth regulators, it resulted in increased growth of maize, leaf area

index, and yield.

MykoPlus

MykoPlus is one of the potential biofertilizer that was founded by Dr. Jocelyn T.

Zarate and her team at the National Institute of Molecular Biology and Biotechnology at

University of the Philippines Los Baños (Pagcaliwagan, B., 2015; DOST-PCAARRD,

2015). As stated by Sarian (2018), MykoPlus is available in powder form and very easy

to apply by only coating the corn seeds by the powder prior to planting, and as a result it

has been shown to work wonders on maize.

MykoPlus enhance crop growth and yield (DOST, 2016; UP, 2016) by assisting

better water and nutrient absorption of plants in the soil with the help of microorganisms

contained in the biofertilizer that also provides additional nutrients through biological

nitrogen fixation, phosphorus solubilization, and growth hormone secretion (Perez,

2019). It is further reported by Rekadwad and Khobragade, (2017), Opeña and Sotto,

(2020) that the microbial biofilm that produced by plant growth promoting

microorganisms such as mycorrhizal fungi and plant-growth promoting rhizobacteria,

enhances the growth and productivity of crops, regulate plant nutrition and enhanced the

production of phytohormones and antioxidant enzymes.

MykoPlus inoculant coated maize seeds showed productive results as it improved

the ability of the crop to assimilate nutrients and higher yield rates compared to crops that

received a 100 percent prescribed chemical fertilizer rate alone. It also noted that residual

nitrogen and phosphorus in the soil is higher as well as it enhanced the crops rooting,

taller shoots, and better survival in flooded soils that were brought by typhoons (DOST-

PCAARRD, 2015).

Fertilizer

Farmers used farm inputs to supply and add nutrients in their plants which results

in improvement in terms of production. Fertilizers, either organic or chemical, play an

important role in agriculture as it offers huge influence. Integration of inorganic

fertilizers with organic manures can be used to increase crop production on a sustainable

basis at optimum rates (Mahmood et al., 2017). In addition, the use of organic manures

alongside inorganic fertilizers also contributes to increased soil organic matter (SOM),

soil structure, water holding capacity and enhanced nutrient cycling in the study of (Saha

et al., 2008) and helps sustain soil nutrient status, cation exchange capacity (CEC) and

biological activity of the soil. Moreover, Mubeen et al., (2013) stated that the combined

use of organic and inorganic fertilizers is therefore considered a good choice for

improving nutrient recovery, plant growth and ultimate yield, otherwise higher N and P

application rates are needed to achieve better maize yields.

Organic manure
 Organic manures are the natural renewable sources of soil organic matter,

containing all the essential plant nutrient elements (Subedi, K.D. and Ma, B.L., 2009). In

many places, livestock manure is a significant source of N for crop production, but

successful manure management is critical to improving the economy of the use of manure

and minimizing the impact on the quality of water (Jokela, 2004). By improving the

physical, chemical and microbiological properties of the soil as well as the nutrient

supply, the use of organic inputs such as crop residues, manures and compost has great

potential to increase soil fertility and crop yield (Stone, D. M. and Elioff, J. D. 1998).

Organic manures have more beneficial effects on soil quality than inorganic fertilizers

thereby improving nutrient release and their availability to the plants (Birkhofer et al.,

2008). In terms of nutrient content animal wastes are generally higher than plant wastes

(Sukartono et al., 2011). Increased maize yield (Anatoliy and Thelen, 2007), higher SOM

content (44 percent), increased soil porosity (25 percent) and 16 times more water

holding capacity were the product of the sole application of farm yard manure (Gangwar

et al., 2006).

Chicken Manure

Both organic and inorganic forms of the plant nutrients are present in chicken

manure as stated by McCall (1980). Phosphorus is primarily organic and becomes

available as the manure decomposes, but all may not be available until the next crop or

season. Potassium is present in the inorganic form and readily available to plants. Other

plant nutrients become available during decomposition of chicken manure.

Inorganic fertilizer
 The use of chemical fertilizers will help to obtain maximum baby maize output,

but keep in mind that chemical fertilizers can have a dangerous impact on environmental

health (Dadarwal et al., 2009). While chemical fertilizers are essential inputs to increase

crop productivity, the decrease in some soil properties and crop yields over time is

correlated with over reliance on chemical fertilizers (Hepperly et al., 2009).

Effects of fertilizer and biofertilizer in corn

The investigation of Abou El-Magd et al. (2006) shows that the use of inorganic

fertilizers alongside with biofertilizers substantially increased maize yield and the same

outcome was obtained by Biswas et. al. (2013) when combined with manure from farm

yards. Moreover, in the study of Singh, et al. (2018) during the early stages of corn,

nitrogen from chemical fertilizer helped promote growth, while phosphate solubilizing

bacteria from biofertilizer increased phosphorus availability, which improved root

growth.
 CHAPTER 3

METHODOLOGY

This chapter presents the research locale, subject of the study, research design,

procedures, data collection, and statistical treatment.

Research Locale

The work was carried out during the second semester of the school year from

May- August 2021 at Southern Luzon State University- Tiaong Campus located at Brgy.

Lagalag, Tiaong, Quezon. It was chosen because the area had already been planted with

corn. It has the environmental requirements that is needed by corn and is also near the

source of water.

Subject of the Study

The variety of corn that was used in this study is white corn, the Los Baños

Lagkitan also known as Philippine Glutinous Composite 2 that was originally developed

in the University of the Philippines Los Baños. This early maturing composite variety

silks in 49 days and is harvested within 70 to 75 days after planting. It can be grown in

any soil type during wet and dry seasons in all regions of the country. The average plant

height is 224 cm and an ear length of 105 cm. It contains the mutant waxy gene (WX),

which is responsible for the glutinous character and has ivory-white kernels. This

composite is composed of crosses among native glutinous varieties, high yielding

Mexican flint varieties and the Los Baños -bred downy mildew resistant varieties. Corn

was planted under a monocropping system. The plants were fertilized with inorganic
fertilizers which are triple 14 and urea, organic fertilizer such as chicken manure, and

their combination. The amount of these nutrients was based on the soil analysis

recommendation. Corn seeds were inoculated with MykoPlus before being subjected to

sowing. 

Research Design

The researcher conducted an experiment using 2 x 4 factorial experiments in

randomized complete block design (RCBD) with 8 treatments and 3 replications. The

treatments are as follows: 

Factor A (M)- Inoculant

M1- MykoPlus

M2- Without MykoPlus

 Factor B (F) - Fertilizer Materials

F1- Chicken Manure

F2- Inorganic Fertilizer

F3- Combination

F4- Without fertilizer

A 676m2 experimental area was divided into three blocks or strata. Each block

was divided into eight (8) plots where eight (8) treatments were assigned randomly.

A pathway of 2m between blocks and 1m between plots was provided to facilitate

weeding, cultivation, watering, harvesting, collection of data and other cultural operations

for corn. 

The experimental layout is shown in Figure 2.

 7.5m 1m 2m

2.5m B1M1F4 B1M2F3 B2M1F1 B2M2F1 B3M1F3 B3M2F4

B1M2F1 B1M1F2 B2M2F3 B2M2F4 B3M2F2 B3M1F4

13m
B1M1F1 B1M2F2 B2M2F2 B2M1F4 B3M1F2 B3M2F3
1m
B1M2F4 B1M1F3 B2M1F3 B2M1F2 B3M2F1 B3M1F1

52m
BLOCK 1 BLOCK 2 BLOCK 3
Figure SEQ Figure \* ARABIC 2. Experimental Field Layout
Legend:
M1F1-MykoPlus with chicken manure
M1F2-MykoPlus with inorganic fertilizer
M1F3-MykoPlus with chicken manure and inorganic fertilizer
M1F4-MykoPlus without fertilizer
M2F1-Without MykoPlus but with Chicken manure
M2F2- Without MykoPlus but with Inorganic fertilizer
M2F3- Without MykoPlus but with Chicken manure and inorganic fertilizer
M2F4-Control

Sampling Techniques

A 3 m2 harvest area was set at the center of the experimental plot where data on

yield parameters such as number of corn ear, length of corn ear and weight of corn per

harvest area was collected. It was also the basis to determine the cost and return in peso

per hectare.

For the observation of growth parameters such as number of days from sowing to

emergence, to flowering, and to maturity, plant height, and fresh and dry mass, ten

representative sample plants were taken randomly outside the harvest area and within the

border plants.

The outline of the sample plot planted with corn is presented in Figure 3.
 7.5m

X X X X X X X X X X Representative
X X X X X X X X X X sample
X X X X X X X X X X
X X X X X X X X X X
2.5m X X X X X X X X X X
3m2 Sample
X X X X X X X X X X harvest area
X X X X X X X X X X
X X X X X X X X X X
X X X X X X X X X X 0.25m
X X X X X X X X X X
Boarder
plants
0.75m
Figure SEQ Figure \* ARABIC 3. Overview of sample plot with corn

Research Procedures

This section presents the cultural operations that were followed in the conduct of

the study.

Collection of Soil Sample

Soil samples were collected from the experimental area randomly before land

preparation. The soil sample collected must be clean from any foreign materials. The soil

sample was pulverized, mixed and air dried.

Soil Analysis
 The soil sample collected was tested using a soil test kit. The data on its N, P, and

K content and pH level was used to determine the fertilizer requirement of the

experimental field.

Procurement of Materials

Prior to the conduct of the experiment, agricultural supplies such as fertilizers,

and others were purchased at the Agricultural Supply shop in Tiaong, Quezon. The

biofertilizer MykoPlus and seeds was purchased at University of the Philippines Los

Baños – Institute of Biotechnology. The chicken manure was purchased from Tantuco

Agricultural Supply shop in Candelaria, Quezon.

Land Preparation

The experimental area was prepared two weeks before planting to obtain good

soil tilt and allow sample time for crop residues, weeds and weed seeds to rot or

decompose. After land clearing, plowing is the next step. Ploughing was done using a

tractor to level the soil, break soil clods and remove weeds and crop debris present in the

area. It was repeated two times, with the interval of one week. After ploughing, cleaning

of the area was done by manual hand picking of crop residues, weeds and other debris

and then lay-outing was followed.

Preparation of the Experimental Area

A 676m2 experimental area was divided into three blocks or strata. Each block

was divided into eight (8) plots where eight (8) treatments were assigned randomly. Each

plot measures 7.5m x 2.5m (18.75m2).

 A pathway of 2m between blocks and 1m between plots was provided to facilitate

weeding, cultivation, watering, harvesting, collection of data and other cultural operations

for corn. 

Application of Treatment

Planting of corn seeds was according to the following factors and treatments:

Factor(s):

Factor A (M)- Inoculant

M1- MykoPlus

M2- Without MykoPlus

 Factor B (F) - Fertilizer Materials

F1- Chicken Manure

F2- Inorganic Fertilizer

F3- Combination

F4- Without fertilizer

Treatments:

M1F1-MykoPlus with chicken manure

M1F2-MykoPlus with inorganic fertilizer

M1F3-MykoPlus with chicken manure and inorganic fertilizer

M1F4-MykoPlus without fertilizer

M2F1-Without MykoPlus but with Chicken manure

M2F2- Without MykoPlus but with Inorganic fertilizer

 M2F3- Without MykoPlus but with Chicken manure and inorganic

fertilizer

M2F4-Control

The amount of fertilizer material that applied was based on the result of soil

analysis particularly P, and K.

Seeds under the treatment of biofertilizer were inoculated by MykoPlus before

planting. This method was called slurry method by which the dry powder inoculant is

mixed with the seed in a container along with a liquid to form a slurry. Water is the most

common liquid used. As per recommendation, spraying of MykoPlus was done on the

10th and 20th day after planting.

Basal application of organic fertilizer which is chicken manure was applied 14

days before planting. Inorganic fertilizers were applied basally (Triple 14) and side dress

(Urea). The fertilizer and its rate were based on the soil test recommendation. Basal

application of inorganic fertilizers was done the same day of planting. In control

treatment, any form of fertilizer was not applied. It was planted with the same variety and

watered but no fertilizer was applied.

The application of the treatments will be shown on the table below:

Table 1. Fertilizer application per treatment

TREATMENT FERTILIZER FETILIZER RATE OF MODE OF TIME OF

GRADE APPLICATION APPLICATIO APPLICATION
N
M1 MykoPlus None 1 pack (300g) Slurry Before
Biofertilizer method, planting,
Spray 10th and 20th
 DAP
F1 Organic Chicken None 7.5 kg Basal 14 DAP
manure
Broadcast
F2 Inorganic T14 14-14-14 402 g/plot Basal At planting
Urea 46-0-0 242 g/plot Side dress 30 DAP
Chicken None 3.75 kg Basal 14 DAP
manure
F3 Broadcast
Combination
T14 14-14-14 201 g/plot Basal At planting
Urea 46-0-0 121 g/plot Side dress 30 DAP
F4 Control Any form of fertilizer was not applied.

Planting

The direct seeding is the planting method that was used. Planting was done by

sowing two seeds per planting hole. Two corn seeds were planted per hill with a distance

of 0.75m between rows and 0.25m between hills with a depth of 2-3 inches. Seeds with

the treatment of biofertilizer were inoculated with MykoPlus before planting, while seeds

without the treatment of biofertilizer will be sown without MykoPlus. Planting was done

manually by hand.

Replanting

Replanting of corn seeds was done 14 days after planting if both of the two seeds

that had been sowed in the hole failed to emerge. Seeds with the treatment of MykoPlus

were planted in a seedling tray as well as the seeds without MykoPlus, separately.

Thinning
 When seedlings have two sets of true leaves, thinning was done at

seedling per hill 20 days after planting (DAP) by uprooting to minimize competition for

nutrients and sunlight. Thinning seedlings is essential for healthy plant growth and

development. The characteristics of seedlings that should remain are the largest and

healthiest seedlings. The seedling has healthy leaves and a green color.

Watering
The source of water is either from rain or from irrigation. During the time of seed

germination, the field was irrigated moderately to encourage deeper penetration of roots,

especially during the flowering stage. Irrigation was done when rainfall was minimal to

attain high yield with the aid of a water pump every morning and afternoon period. The

way of watering is manually using pail, dipper and watering can per plot not by flooding

to avoid the leaking of water from each treatment.

Crop Maintenance

Weeding was done by hand until before tasseling to avoid damaging the plant.

Hilling up was done three weeks after plant emergence to destroy germinating weed

seeds and to help support the plant.

Control of Pest and Diseases

Regular monitoring was done for occurrence of insects and diseases and proper

pest control was employed to avoid reduction of yield and quality of the harvest.

Harvesting

Harvesting of crops was done 70-75 days after planting or 2-3 weeks after

flowering depending on the weather condition and the hybrid maturity itself. Ears were
harvested when the corn husk was still green, the silk color turned brown and the corn

ears were full and hard to feel. Harvesting was done manually.

Post-Harvest Activities

Ears were harvested, dehusk then sorted if it is marketable or not. By this time the

corns are ready for storage or selling. Whole and clean grains are preferred by waxy corn

grain processors since this is intended for food and buyers that will give higher prices.

Data Collection

To answer the objectives of this study the following data was gathered:

Growth Parameters

The following growth parameters for corn was collected at the ten representative

samples outside the harvest area:

Number of Days from Sowing to Emergence. This was done by counting the days

from the day of sowing to the emergence of shoot.

Number of Days from Emergence to Flowering. This was done by counting the

number of days from emergence to the time the flower will be observed. 

Number of Days from Flowering to Harvesting. This was done by counting the

number of days from the appearance of flowers to the day of harvest.

Weekly Plant Height. This was collected for corn only wherein it was done by

measuring the height of the plant from the base up to the tallest leaf by using a meter

stick (cm). This was done in a weekly interval from the week after emergence.
 Weekly Number of Leaves. This was done by counting the number of leaves

weekly. Counting of leaves start from the lowest to the last leaf that is arched over or the

tip is pointing down. Younger leaves that are standing straight up are not counted.

Length of Roots. This was done by measuring the length of roots by using a meter

stick (cm).

Fresh Biomass. Plant fresh biomass was collected after harvest. It was done by

weighing separately each plant part which are the roots and shoots in a weighing scale

(kg).

Dry Mass. Plant dry mass was collected after subjecting the roots and shoots to

oven drying under 1200C for 8 hours and weighing in a weighing scale (kg) separately.

Yield Parameters
The following yield parameters was collected at the harvest area assigned at the

center of each plot:

Length of Corn Ear. This was done by measuring the length of each corn ear

harvested at the harvest area. This was done with the use of measuring tape (cm).

Weight of Ear. This was done by weighing each corn ear harvested at the harvest

area. This was done with the use of a digital weighing scale (g).

Diameter of Ear was measured in the middle part of the same ears harvested using

vernier caliper.

Number of Corn Ear per Harvest Area. This was done by counting the total

amount of corn per harvest area.

 Weight of Harvested Corn Ear per Harvest Area. This was done by weighing the

total volume of corn per harvest area.

Computed Yield per Hectare. The computed yield per hectare was measured by

dividing the total yield of corn per 3m2 harvest area then multiplied by 10,000m2. The

formula to be used is shown below:

Total Yield (kg)

Computed Yield per Hectare = X 10,000m2
Harvest Area

Number of Marketable Corn Ear. This was done by counting the number of marketable

ears manually after harvest. Marketable corn condition has its characteristics such as

good kernels, complete grains in the kernel rows, no discoloration of grains, and no sign

of damage by insect or mechanical. Those which passed the standard requisite were

considered as marketable produce.

Number of Non-marketable Corn Ear. This was done by counting the number of

non-marketable ears manually after harvest. Non-marketable corn condition has

characteristics that may not be liked by the consumers such as incomplete kernels,

discoloration and damage on ears by the insect or mechanical.

Nutrient Uptake

Helps identify and monitor a crop’s nutrient status and how well plants utilize the

soil and applied nutrients.

P and K in plant tissue. It requires sampling a certain plant part at a given stage of

growth. Two leaves from the last matured plant after tasseling in the harvest area were
used for plant tissue analysis. The sample plant leaves were analyzed at Southern Tagalog

Integrated Agricultural Research Center (STIARC) at Lipa City. P and K amount are the

plant nutrients that were analyzed in the tissue.

Agronomic Parameters

Harvest Index.  This was computed by dividing the grain yield by the total

biomass (stover plus grain). Corn stover is made up of the stalk, leaves, husks and tassels

left in the field after harvesting the grain

The formula to be used is shown below:

Harvest index = Grain Yield

X 100
Total biomass
(grain+stover)

Pest and Disease Incidence

This was determined by observing the plants in the representative samples and by

gathering insect pests, weeds, and infected plant parts. It was hand picked to remove and

identified to note its occurrence.

Cost and Return

The cost and return of plants were estimated based on the prevailing market price

of corn grains in the area. It was based on the computed yield per hectare.

Gross Profit. This is calculated using the formula:

Gross Profit = Revenue – Cost of Goods Sold

 Return on Investment. This is calculated using the formula:

Net income
X 100
Total Expenditures

Statistical Treatment

Collected data was organized and presented in textual and statistical tables then

analyzed following the Analysis of Variance (ANOVA) in Randomized Complete Block

Design (RCBD) under 4x2 factorial experiment. Significant results from ANOVA will

be subjected to further statistical analysis using Least Significant Differences (LSD).

To facilitate easy computations, the data was analyzed using Statistical Tool for

Agricultural Research (STAR) software version 2.0.1.

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