CHAPTER 1
INTRODUCTION If we value the pursuit of knowledge, we must be free to follow wherever that search may lead us. The free mind is not a barking dog, to be tethered on a ten-foot chain. Adlai E. Stevenson Stevenson Jr. Jr. (1900 – 1965) Corn is an important important crop in the Philippines. Philippines. Just like rice, it is also a staple for Filipinos specifically those from the Southern Philippines. Data from the Bureau of Agricultural Statistics reveal that the country is almost sufficient in corn at 99%. Our sufficiency ratio has gone up over the years from 96% in 2001 to 99% in 2004-2005. However, if you look at the country’s needs on a per corn variety basis, the country is deficient in yellow corn production. The general varieties of corn planted are yellow and white corn. Yellow corn is the one used for feeds. White corn is the variety preferred for food in the country although yellow is edible as well. The requirement requirement for yellow corn for feeds is pegged pegged at 3.414 MMT in 2005 while production was at 3.01 MMT only. only. This places places our self-sufficienc self-sufficiency y ratio for yellow yellow corn at 88%. Our demand for feeds is around 64% of the total demand for corn and only about 22% of supply is consumed as food. Other uses of corn are for seeds (1%) and processing (13%).The production doesn’t seem to match this demand for yellow corn. About 43% of the total corn production is devoted to white while the rest is for yellow. In terms of production areas, 61% of the total area for corn is devoted to white corn production and only 39% was devoted for yellow corn production. The corn sector is a vital industry. Addressing Addressing the needs of the corn sector would also lead to benefiting its allied industries livestock and poultry sectors, etc. The competitive competitive advantage advantage of local livestock livestock and poultry in the domestic domestic and export markets will depend on the cost-efficiency of the domestic corn industry. Corn, on the
other hand will have to contend with cheaper imported corn and feed substitutes. Corn in terms of importance, remains second only to rice. The sector received very little public investment compared to rice. Standard sweet corn is a mutant type of corn that differs from field or dent corn by a mutation at the sugary (su ( su)) locus. The sweet corn (su ( su)) mutation causes the endosperm (storage area) of the seed to accumulate about two times more sugar than field corn. Today several hundred sweet corn varieties are available. Recently, a numbe numberr of new mutan mutants ts have have been been used used to impr improv ove e swee sweett corn corn eatin eating g quali quality ty,, particularly the sugary enhanced (se ( se)) and shrunken-2 (sh (sh2) genes. Sweet Sweet corn is the result result of a naturall naturally y occurri occurring ng recessiv recessive e mutatio mutation n in the genes which control conversion of sugar to starch inside the endosperm of the corn kernel. Unlike field corn varieties, which are harvested when the kernels are dry and mature (dent stage), sweet corn is picked when immature (milk stage) and prepared and eaten eaten as a vegetab vegetable le,, rather rather than a grain. grain. Since Since the process process of maturati maturation on involves converting sugar to starch, sweet corn stores poorly and must be eaten fresh, canned, or frozen, before the kernels become tough and starchy. A major economic pest of corn in the Philippines is the Asian corn borer of the stem borer complex. Measuring only 1/50 of an inch, parasitoids are the Asian corn borer's worst enemy and the corn farmers' dearest ally in their war against Asia's most important corn pest. Parasitoids kill by laying their eggs inside the pupa of the Asian corn borer. The hatched newborns feed off the body, eventually killing the host or the borer. Yield reduction due to a 40–60 % corn borer infestation can reach as high as 27%. In 1986, Bt corn, originally developed to control the European corn borer, was proven to also confer a high level of resistance against the Asian corn borer borer.. Bt stand stands s for for Bacillus Bacillus thuringiensis thuringiensis,, a bact bacteri eria a that that produ produce ces s a powe powerfu rfull
insecticide. The gene traits of the bacteria have been integrated into the corn genes to resist the corn borer. However, the introduction of Bt in the Philippines has been controversial due to environmental and consumer concerns. The most common control strategies in corn production – sweet corn or ordinary variety of corn, are the mechanical and biological control strategies. Mechanical strategies in corn production involve weed control. Weed control is still one of our most useful weed control tools. Both primary tillage and cultivation should be considered for specific weed problems. Perennial broadleaf weeds are an increasing problem in no-till corn production. In some cases, these weeds cannot be controlled without tillage to disrupt underground perennial parts. The use of the moldboard plow is an effective method of control and, for some weeds, represents the only practical method of control. The first step in an effective weed control program is proper weed identification. Only by knowing the exact identities and relative infestations of weeds on a field-by-field basis can the proper weed control strategy be developed. Continued use of the same program, or use of reduced tillage practices, can result in changes in weed infestations. Biological
control
strategy
in
corn
production
involves
the
use
of
Trichogramma. Trichogramma are among the smallest of insects, having a wingspread of about 1/50th of an inch. Despite its size, it is an efficient destroyer of eggs of many moth and butterflies which are the leaf-eaters in the larval stage. These parasitic insects disperse readily in their search for over 200 species of eggs to parasitize. The Trichogramma seeks out eggs, but does not feed on or harm vegetation. It is effective tool because it kills its host before the plant can be damaged. They can be used in a variety of crops as well as in horticultural and ornamental plants.
Trichogramma are used extensively in a variety of crops
including cotton, corn, tomatoes, avocados, walnuts, pecans, apples, alfalfa, etc. The cost is so low that it is feasible to purchase them for massive releases. The main purpose for the development of these control strategies is to provide effective resistance/protection against pests. As stated above, one of the major pests that is dominant in Philippine corn farms is the Asian corn borer. Studies have shown that yield losses due to corn borer infestation could range from a low of 4.3% to a high of 30.9%. The damage was more pronounced during the wet season. Farmers commonly apply insecticides to protect corn plants against the Asian corn borer. But this practice has now become less appealing due to health and environmental concerns. It is therefore expected that farmers will find other means wherein they will lessen cost and, at the same time, increase yield. Farmers adopt new technologies mainly to improve their financial performance in farming. At the farm level, the reduction in pest damage translates to better yield and income in corn farming. The experiences in many countries revealed that the resistance of corn plants to the corn borer reduces pesticide application and damage to corn plants, thereby, increasing yields. Concern about present levels of pesticide use has prompted many agriculturalists to reevaluate current practices and policies. Water quality concerns and the trend to use fewer inputs have renewed interest in mechanical weeding to reduce herbicide use and weed control costs. This study aims to provide an accurate and appropriate assessment on the effects of the mechanical and biological control strategies on sweet corn production in Davao City. Results of this study would most likely help farmers assess whether or not to stick to these two current control strategies.
RESEARCH QUESTIONS A.General Statement of the Problem: This study generally aims to assess the
effects of the mechanical and biological control strategies in sweet corn production in Davao City. B.Specific Statement of the Problem: Specifically, this study aims to answer the following questions: 1.
What is sweet corn? How is it different from other corn
varieties? 2.
What is the current status of sweet corn production in
Davao City? 3.
What are the pests that attack corn fields? What is a corn
borer? How does it affect the quality and quantity of sweet corn? 4.
What government agency is tasked in remedying this
problem? What are the present efforts of this agency vis-à-vis the problem? 5.
What are the mechanical strategies institutionalized to
control the pests that attack corn fields? 6.
What are the biological strategies institutionalized to
control the pests that attack corn fields? 7.
How is the effectiveness of these aforementioned control
strategies assessed?
OBJECTIVES OF THE STUDY
A.General Objective of the Study: This study generally aims to assess the effects of the mechanical and biological control strategies in sweet corn production in Davao City. B.Specific Objectives of the Study: This study has the following specific objectives. 1.
To know what sweet corn is and to be able to differentiate
it from other existing corn varieties; 2.
To be acquainted with the current status of sweet corn
production in Davao City; 3.
To be familiar with the pests that attack corn fields, to be
able to distinguish these pests with the corn borer, and consequently, to identify how the latter affect the quality and quantity of sweet corn produced; 4.
To identify the government agency tasked in remedying
this pest problem and likewise outline the present efforts of this agency vis-à-vis the problem; 5.
To be on familiar terms with the mechanical strategies
institutionalized to control the pests that attack corn fields; 6.
To
determine
what
are
the
biological
strategies
institutionalized to control the pests that attack corn fields; and 7.
To
establish
how
is
the
effectiveness
aforementioned control strategies being assessed.
of
these
OPERATIONAL DEFINITION OF TERMS
Biological
control
strategies
involve
the
use
of
Trichogramma.
Trichogramma are among the smallest of insects, having a wingspread of about
1/50th of an inch. Despite its size, it is an efficient destroyer of eggs of many moth and butterflies which are the leaf-eaters in the larval stage. These parasitic insects disperse readily in their search for over 200 species of eggs to parasitize. The Trichogramma seeks out eggs, but does not feed on or harm vegetation. It is effective tool because it kills its host before the plant can be damaged. BT stands for Bacillus thuringiensis, a bacteria that produces a powerful
insecticide. The gene traits of the bacteria have been integrated into the corn genes to resist the corn borer. The first commercial release of Bt corn in the Philippines was approved by the Department of Agriculture in 2002.
An ex-ante analysis also
revealed a yield advantage of as much as 41% of Bt corn over non-Bt varieties with profitability gains of 15–86%. Sweet corn (Zea mays convar. saccharata var. rugosa; It is also called Indian corn, sugar corn, and pole corn ) is a variety of maize with a high sugar content.
Sweet corn is the result of a naturally occurring recessive mutation in the genes which control conversion of sugar to starch inside the endosperm of the corn kernel. Unlike field corn varieties, which are harvested when the kernels are dry and mature (dent stage), sweet corn is picked when immature (milk stage) and prepared and eaten as a vegetable, rather than a grain. Mechanical control strategies in corn production involve weed control. The
organic farmer has many options to reduce weed problems such as crop rotation,
intercropping, allelopathy, mulches, clean seed, cultivar selection, and can also play around with seeding rate, seeding date, and row spacing to minimize weed invasion. Despite all these tools, many will still have to rely on some form of mechanical weed control. In crops such as soybean, corn, and small grains (wheat, barley, oats) many organic farmers are turning towards two types of mechanical weeding equipment, namely the rotary hoe and the finger-weeder (flex-tine harrow).
SIGNIFICANCE OF THE STUDY
This study will give a more comprehensive picture of the direct effects of the identified control strategies vis-à-vis the quality and quantity of sweet corn yield. This study will likewise assess the propriety of these control strategies, which consequently will give feedback to the farmers and to the proper implementing agencies tasked in handling agricultural related issued, as to the aptness of the said control strategies. This study is very important for its timeliness and its relevancy considering the fact that these control strategies has been practiced since time immemorial and there has been significant innovations relative to the same problem these strategies seek to remedy. Substantially, this study will shed light as to whether or not these control strategies positively affect the quantity and quality of sweet corn production in Davao City. Theoretically, this study will offer an important contribution to the body of knowledge on the qualitative approach to monitoring and evaluation of programs.
SCOPE AND LIMITATIONS OF THE STUDY
The results presented in this paper should be interpreted carefully as they are will be based on just one year of cropping experience. Should there be tangible results presented, these may change over time as changes occur in technology, farmers’ and consumers’ perception, public support and seed stakeholders’ participation.
CHAPTER II REVIEW OF RELATED LITERATURE PHILIPPINE CORN INDUSTRY
Data from the Bureau of Agricultural Statistics reveal that the country is almost sufficient in corn at 99%. Our sufficiency ratio has gone up over the years from 96% in 2001 to 99% in 2004-2005. However, if you look at the country’s needs on a per corn variety basis, the country is deficient in yellow corn production. The general varieties of corn planted are yellow and white corn. Yellow corn is the one used for feeds. White corn is the variety preferred for food in the country although yellow is edible as well. According to Mr. Jess Binamira, former DA Corn Director, yellow corn is highly preferred in Mexico for food because of its yellow fat while in the Philippines, it
is preferred for feeds also for the yellow fat because it gives poultry and hogs a good color. The requirement for yellow corn for feeds is pegged at 3.414 MMT in 2005 while production was at 3.01 MMT only. This places our self-sufficiency ratio for yellow corn at 88%. Our demand for feeds is around 64% of the total demand for corn and only about 22% of supply is consumed as food. Other uses of corn are for seeds (1%) and processing (13%). The production doesn’t seem to match this demand for yellow corn. About 43% of the total corn production is devoted to white while the rest is for yellow. In terms of production areas, 61% of the total area for corn is devoted to white corn production and only 39% was devoted for yellow corn production. Food use is only about 1.147 million metric tons while the white corn production was 2.251 MMT leading to a surplus of about 1.1 million metric tons in 2005. In a roundtable discussion on the corn industry, Director Binamira however failed to give a concrete answer on where the surplus in white corn goes. The biggest corn producing provinces are Isabela and Bukidnon. Corn productivity over the last 5 years is said to be low at an average of 1.98 tons per hectare. Farmers are largely using native Tinigib varieties and Open Pollinated Varieties (OPV) corn seeds. Over the last two years, the yield per hectare has reached the 2 tons per hectare mark.
SWEET CORN
Field corn is produced primarily for animal feed and industrial uses such as ethanol, cooking oil, etc. In contrast, sweet corn is produced for human consumption as either a fresh or processed product. The specific time when sweet corn originated
cannot be pin-pointed; however, sweet corn was grown by the American Indian and first collected by European settlers in the 1770's. The first variety, Papoon, was acquired from the Iroquois Indians in 1779. Standard sweet corn is a mutant type of corn that differs from field or dent corn by a mutation at the sugary (su) locus. The sweet corn (su) mutation causes the endosperm (storage area) of the seed to accumulate about two times more sugar than field corn. Today several hundred sweet corn varieties are available. Recently, a number of new mutants have been used to improve sweet corn eating quality, particularly the sugary enhanced (se) and shrunken-2 (sh2) genes. The se varieties, also called Everlasting Heritage (EH), are well-suited for local market production because they contain more sugars than the normal (su) sweet corn and therefore will remain sweet about two to four days after harvest if refrigerated. The se varieties can be grown in the same manner as su corn. Sugary enhanced hybrids and normal sweet corn varieties do not require isolation from each other. The shrunken 2 (sh2) sweet corn, also called supersweet, has two main advantages over the other types: 1) it is at least two to three times sweeter, and 2) the conversion of sugar to starch is negligible, thus this corn type will remain sweet up to 10 days after harvest
if
cooled
properly,
then
refrigerated.
Because
of
these
advantages, sh2 varieties exclusively should be grown for sales to distant markets. The demand for sh2 corn is increasing at local markets, also. The sh2 sweet corns must be isolated at least 300 ft from all corn types, otherwise the corn will be starchy if cross pollinated. Besides isolation, cross pollination can be prevented by varying planting dates or selecting varieties such that
the pollination stage (silking date) does not coincide among corn types. For varieties requiring similar time for development, planting dates for each variety must be more spread apart early than later in the growing season to avoid cross pollination. This is because temperatures are cooler (less heat unit accumulation) in the early versus late spring plantings. INNOVATIONS AND CHALLENGES AGAINST THE CORN INDUSTRY
Since many of the corn farmers are subsistence in nature, addressing their issues would help improve their lot. Their production issues are also not very different from rice and other crops. Their yield per hectare is relatively low according to Mr. Butch Umengan of the National Corn Competitiveness Board. Almost all of the corn farms are rainfed. Obviously, the yellow corn production has to be increased. Corn quality needs to be improved also. According to PAFMI, they prefer imported corn than locally-grown corn. The imported corn normally meets the 14 percent moisture content requirement that would prevent the formation of cancercausing aflatoxin.The productivity issue also brings to fore the contentious issue of the use of BT corn. The commercialization of Bt corn is still allowed although the Department of Agriculture has not pursued it with the same vigor as during the time of Sec. Cito Lorenzo. This implies that the BT corn issue will remain and this is something that organizations, like R1, that are opposed to genetic engineering of life forms, such as crops should think about as it tries to develop further its campaign and analysis on GMOs.
BT CORN and ITS EFFECT
A major economic pest of corn in the Philippines is the Asian corn borer of the stem borer complex. Yield reduction due to a 40–60 % corn borer infestation can
reach as high as 27% (Logroño 1998). In 1986, Bt corn,
originally developed to
control the European corn borer, was proven to also confer a high level of resistance against the Asian corn borer (Fernandez et al. 1997). Bt stands for Bacillus thuringiensis, a bacteria that produces a powerful insecticide. The gene traits of the bacteria have been integrated into the corn genes to resist the corn borer. However, the introduction of Bt in the Philippines has been controversial due to environmental and consumer concerns. The first commercial release of Bt corn in the Philippines was approved by the Department of Agriculture in 2002.
An ex-ante
analysis also revealed a yield advantage of as much as 41% of Bt corn over non-Bt varieties with profitability gains of 15–86% (Gonzales 2002). While initial studies indicated the strong potentials of Bt corn in the Philippines under controlled conditions, yield, costs, resource use and profitability may significantly vary from experimental results under farmers’ fields and management. The commercial introduction of Bt corn in the domestic market presents considerable options to farmers in improving their financial performance by lowering cost of production and increasing yields. The experiences in many countries revealed that the resistance of corn plants to the corn borer reduces pesticide application and damage to corn plants, thereby, increasing yields. In 2002, the Philippines approved Bt corn Mon 810. This gene is incorporated into the different commercial local corn varieties of Monsanto Philippines and Pioneer Hi-bred Philippines. Locally, the Monsanto Bt corn hybrids are known as Dekalb(DK) 818YG, DK9161YG, and DK9051YG. On the other hand, the local Bt corn hybrid varieties of Pioneer Hi-bred Philippines are sold as 30Y84, 30Y50, 30Y80, 30Y73, and 30Y34. In 2005, another Bt corn-event Bt 11 of Syngenta Philippines was approved for
planting. The biotech crop products of Syngenta Philippines are marketed under the Agrisure trade name. For the approved Bt 11, its commercial variety is sold as NK 5447Bt. Also in 2005, Corn NK 603 was approved for commercial use. It introduced the EPSPS gene into the chromosome of the corn plant. Designed as a weed control option, this corn type which is developed by Monsanto Phils. is known as RR corn or Roundup Ready Corn. It is sold as DK818RRC2. The approval of stacked-trait corn-Bt corn Mon810/NK 603 makes it the fourth event to be given the go signal by the Philippine government. The commercial technology demonstration of the corn hybrid varieties bearing the dual traits will start in 2005 dry season planting. Adding to the menu of agri-technology choices available to farmers, the Philippines' Bureau of Plant Industry recently approved a new corn variety for planting. So called "stacked-trait corn," the plant bears two introduced genes in its genetic make-up. The first one called Bt gene (cry1ab) comes from a common soil bacterium, Bacillus thuringiensis. This makes protein that enables the corn plant to resist the attacks of Asiatic corn borer, a dreaded insect pest that can cause as much as 80% yield reduction.
EXISTING CORN PEST CONTROL STRATEGIES
The most common control strategies in corn production – sweet corn or ordinary variety of corn, are the mechanical and biological control strategies. Mechanical strategies in corn production involve weed control. Weed control is still one of our most useful weed control tools. Both primary tillage and cultivation
should be considered for specific weed problems. Perennial broadleaf weeds are an increasing problem in no-till corn production. In some cases, these weeds cannot be controlled without tillage to disrupt underground perennial parts. The use of the moldboard plow is an effective method of control and, for some weeds, represents the only practical method of control. The first step in an effective weed control program is proper weed identification. Only by knowing the exact identities and relative infestations of weeds on a field-by-field basis can the proper weed control strategy be developed. Continued use of the same program, or use of reduced tillage practices, can result in changes in weed infestations. Biological
control
strategy
in
corn
production
involves
the
use
of
Trichogramma. Trichogramma are among the smallest of insects, having a wingspread of about 1/50th of an inch. Despite its size, it is an efficient destroyer of eggs of many moth and butterflies which are the leaf-eaters in the larval stage. These parasitic insects disperse readily in their search for over 200 species of eggs to parasitize. The Trichogramma seeks out eggs, but does not feed on or harm vegetation. It is effective tool because it kills its host before the plant can be damaged. They can be used in a variety of crops as well as in horticultural and ornamental plants.
Trichogramma are used extensively in a variety of crops
including cotton, corn, tomatoes, avocados, walnuts, pecans, apples, alfalfa, etc. The cost is so low that it is feasible to purchase them for massive releases.
TRICHOGRAMMA
Measuring only 1/50 of an inch, parasitoids are the Asian corn borer's worst enemy and the corn farmers' dearest ally in their war against Asia's most important corn pest. Parasitoids kill by laying their eggs inside the pupa of the Asian corn borer.
The hatched newborns feed off the body, eventually killing the host or the borer. It is reported that T. cnaphalocrocis showed the highest potential in controlling the corn borers since it was the most abundant and most capable of parasitizing the borers in the field. T. cnaphalocrocis parasitizes the pupa of the borers for at least 40 days starting as early as the silk stage until the corn plant is already mature. Parasitized pupa can be distinguished from the unparasitized pupa as smaller, rigid and darker in color. The parasitoids emerge from the parasitized corn borer pupa 1 to 5 days after the pupal period (5 to 8 days) of the corn borers. The male would scratch the female's ovipositor and crawl on the dorsal part of the abdomen touching the body of the female. Afterwards, the male would pin down the female by gripping the female's abdomen with its legs. The female becomes still while the male continues to scratch the female's body after which the male attaches its claspers into the serrated rear of the female's ovipositor. When this is done, the mating pair turns away from each other while still attached at their rear ends. This position enables the pair to fly even during copulation. The scientists reported that T. cnaphalocrosis usually mate from 8 am to 5 pm for 3-4 hours. The T. cnaphalocrocis female lay its eggs on corn borer larvae that are found outside the corn stalks. Adult parasitoids emerge from the pupa and the third, fourth, and fifth instar larvae. The scientists reported that percent parasitization could range from 60 to 86%. This means that before corn borer larvae (3rd or 4th instar) move into the corn stalks, they already harbor the parasitoids. It was also found that the female parasitoid prefers to lay its eggs on older than younger larvae since adult parasitoids only emerge from the older larvae. Among the three larval-pupal parasitoids, T. cnaphalocrocis showed the most
promise as an effective biological control agent against the Asian corn borer. It has the potential; for commercialization and mass rearing. The scientists are optimistic that if this potential is tapped, T. cnaphalocrocis can be used to control Asian corn borer at the whorl stage of the corn plant.
CHAPTER III CONCEPTUAL FRAMEWORK Figure 1 Interplay of Factors Affecting the Quality and Quantity of Sweet Corn Yield
Figure 1 enumerates the factors to be assessed in determining the quality and quantity of sweet corn yield in Davao City. The independent variables critical to the said
study are: MECHANICAL CONTROL STRATEGY and BIOLOGICAL CONTROL
STRATEGY. The dependent variable is the quality and quantity of sweet corn yield in Davao City. The
illustrated
conceptual
framework
depicts
aforementioned dependent and independent variables.
the
interplay
of
the
CHAPTER IV METHODOLOGY
Research Design
The process of inquiry used for this evaluation study is the descriptive correlational design research. This design involved the collection of data to answer questions on the current status of the subject under study, and to describe in both qualitative and quantitative terms the degree to which the factors are related and determines whether and to what degree a relationship exist between two or more variables. In this study, data will be collected to determine whether and to what degree the independent variables, such as the mechanical control strategies and biological control strategies, are associated with the dependent variable --- quality and quantity of sweet corn yield. The process of inquiry used for this evaluation study is primarily participatory
and qualitative. A qualitative approach was chosen because the focus of the evaluation is to capture the changes in the yields of the respondents. According to Merriam (1998; cited in Cagasan, 2005), qualitative study design is appropriate when researchers are interested in insight, discovery, and interpretation rather than hypothesis testing.
Participants of the study
The participants of this study will be the randomly-selected sweet corn producers. A separate total and sample population shall be identified for each control strategy. A sample population of twenty percent (20%) of the total number of identified sweet corn producers per district, using the mechanical control strategy shall be surveyed by the researcher using the survey appended. Likewise, a separate sample population of twenty percent (20%) of the total number of identified sweet corn producers per district, using the biological control strategy shall be surveyed by the researcher using the survey appended.
Locale of the Study
This study shall be conducted within the different districts of Davao City wherein majority of the sweet corn producers reside, as reflected in the records of the implementing agency. The following districts are as follows: District 1 – Talomo District 2 – Buhangin, Bunawan, Paquibato District 3 – Baguio, Marilog, Toril, Tugbok, Calinan
Research Instrument
In order to gather information needed for the study, a survey questionnaire will be drafted for the target respondents. This instrument will be tested to determine its validity and reliability prior administration. Attached as an appendice of this paper is the sample survey questionnaire that will be used. Procedure of the Study
Problem identification is the first stage of this study. The variables are determined and arranged to formulate the Research Paradigm. Upon determination of the conceptual framework, the survey questionnaire is drafted and tested for validity and propriety. Statistical Treatment of Data
The following statistical tools will be used in the analysis and interpretation of data. 1.Descriptive statistics such as frequency counts and weighted mean to describe the status of the mechanical control strategy, biological control strategy, and the quantity and quality of sweet corn yield in Davao City. 2.Pearson Product Moment Correlation will also be used to find out whether a significant relationship exists between the independent and dependent variables of the study. 3.Multiple Regression Analysis will likewise be utilized to determine which of the independent variables significantly influence the quantity and quality of sweet corn yield in Davao City.
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