CHAPTER ONE
1.1 INTRODUCTION
Wheat is a cereal grain, originally from the Levant region of the Near East but now cultivated worldwide In 2013 world population of wheat was 713 million tons make it a third most-produced cereal after maize and rice
Wheat is counted among the ‘big three’ cereal crops, with over 600 million tones being harvested annually. For example, in 2007, the total world harvest was about 607 m tones compared with 652 m tones of rice and 785 m tones of maize (http://faostat.fao.org/). However, wheat is unrivalled in its range of cultivation, from 67 N in Scandinavia and Russia to 45 S in Argentina, including elevated regions in the tropics and sub-tropics (Feldman, 1995). It is also unrivalled in its range of diversity and the extent to which it has become embedded in the culture and even the religion of diverse societies.
Wheat (Triticum aestivum L. em Thell.) is the first important and strategic cereal crop for the majority of world’s populations. It is the most important staple food of about two billion people (36% of the world population). Worldwide, wheat provides nearly 55% of the carbohydrates and 20% of the food calories consumed globally (Breiman and Graur, 1995). It exceeds in acreage and production every other grain crop (including rice, maize, etc.) and is therefore, the most important cereal grain crop of the world, which is cultivated over a wide range of climatic conditions and the understanding of genetics and genome organization using molecular markers is of great value for genetic and plant breeding purposes. The grass family Poaceae (Gramineae) includes major crop plants such as wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), oat (Avena sativa L.), rye (Secale cereale L.), maize (Zea mays L.) and rice (Oryza sativa L.). Triticeae is one of the tribes containing more than 15 genera and 300 species including wheat and barley. Wheat belongs to the tribe Triticeae (= Hordeae) in the grass family Poaceae.
Wheat is an edible grain, one of the oldest and most important of the cereal crops. Though grown under a wide range of climates and soils, wheat is best adapted to temperate regions with rainfall between 30 and 90 cm. Winter and spring wheats are the two major types of the crop, with the severity of the winter determining whether a winter or spring type is cultivated. Winter wheat is always sown in the fall; spring wheat is generally sown in the spring but can be sown in the fall where winters are mild. Therefore, today wheat is grown all over the world, with different varieties sown according to the various climates. In 2002, the world’s main wheat producing regions were China, India, United States, Russian Federation, France, Australia, Germany, Ukraine, Canada, Turkey, Pakistan, Argentina, Kazakhstan and United Kingdom (FAO, 2003). Most of the currently cultivated wheat varieties belong to hexaploid wheat (Triticum aestivum L.), which is known as common bread wheat and valued for bread making. The greatest portion of the wheat flour produced is used for bread making. Wheat grown in dry climates is generally hard type, having protein content of 11-15 percent and strong gluten (elastic protein).
1.2 VARIETIES OF WHEAT
ü Common wheat; sometime called “bread wheat” is the most widely grown species, and yields the flour we buy the bag. This wheat is the chife ingredient in commercial foods, such as loaf and raised breads, tortillas, doughnuts and cakes, and East Asian noodles.
ü Durum wheat; is used in most dried pasta couscous, for raised and flat breads in parts of Europe and the Middle East and less often, in the united States for raised breads.
ü Ancient Wheat Varieties; are currently grown on smaller acreages in the united State than common and durum wheats. Whereas the kernels of the latter two are released from their hulls by threshing, those of ancient wheats remain enclosed in inedible hulls after threshing.
SOME NUTRITIONAL VALUES OF WHEAT
Wheat is probably the most common cereal available all over the world and is in even higher demand in recent years due to its abundant health benefits. Over the years, wheat has shown itself to be one of the most successful and sustainable cereals crops in the world. It originated in southwestern Asia, but today it is grown in countless countries. Commonly, wheat cultivation is done at higher latitudes and is primarily used for baking bread products.
Foods like bread, pasta, crackers, bagels, cakes, and muffins are just a few common examples of wheat sources. Wheat is believed to be one of the most wholesome food items, and it ensures a diet rich in nutrients.
Research has already proven that wheat is extremely beneficial for healthy living. Wheat considerably lowers the hazards of heart diseases, owing to its comparatively low fat content. It also regulates blood glucose levels in diabetic patients.
Wheat is able to provide you with an immense energy source due in all parts of the grain kernel, including the bran, germ, and endosperm. The nutrient value of wheat is retained even after processing it into flour. However, if you wish to get the maximum benefit out of wheat products, it’s advisable to choose wheat products that are made from whole-wheat flour rather than the refined varieties.
Wheat Varieties
The health benefit of wheat greatly depends on the form in which you consume it. While whole wheat is extremely nutritious, the benefits of wheat are reduced if you eat bleached white flour which is obtained by processing after only 60% extraction from the grain. In the United States, most wheat products undergo 60% extraction; we see this in noodles, breads, and pasta, as well as in baked goods like rolls, biscuits, and cookies. In these foods 40% of the original wheat grain was removed, and you get only the remaining 60%. Usually the 40% that is removed – the outer brown layer – contains the highly nutritious bran and the germ of the wheat grain. In the process of making 60% abstraction flour, more than half of the vitamin B1, B2, B3, E,calcium, phosphorus, folic acid, copper, zinc, iron, and fiber are lost. If we buy 100% whole wheat products, we are assured of all the nutrients of the bran and the germ, as well as the endosperm.
In recent years, the nutritional value of whole wheat is being recognized by consumers. Low-carb diets and an increase in the whole wheat cereal market are prevalent around the world, especially in the Mediterranean. Just like in whole wheat, wheat germ is a rich source of nutrients. Wheat germ has an abundance of vitaminsand minerals, but it is particularly rich in vitamin E. Wheat germ is known to be a main source of the vitamin B complex in dietary structures throughout the world, and includes vitamins like thiamin, folic acid, vitamin B6and minerals like manganese, magnesium, and zinc. The wheat germ oil improves strength and increases life span.
Nutritional Value of Wheat
Wheat is rich in catalytic elements, mineral salts, calcium, magnesium, potassium, sulfur, chlorine, arsenic,silicon, manganese, zinc, iodide, copper, vitamin B, and vitamin E. This wealth of nutrients is why wheat is often used as a cultural base or foundation of nourishment. Issues like anemia, mineral deficiencies,gallstones, breast cancer, chronic inflammation, obesity, asthenia, tuberculosis, pregnancy problems and breastfeeding problems are quickly improved by consuming whole wheat. Wheat is also recommended to treat sterility. Since germinated wheat comprises 2 or 3 times more vitamin B than common wheat; the seeds are used for useful for treating gastrointestinal conditions, skin diseases, respiratory illnesses, and cardiovascular ailments. Wheat is also known to help balance cholesterol levels and protect the heart.
HEALTH BENEFITS OF WHEAT
ControlsObesity (especiallyinwomen): Wheat has a natural ability to control weight in everyone, but this ability is more pronounced among women. The American Journal of Clinical Nutrition has shown through research that whole wheat, rather than refined wheat, is a good choice for obese patients. Women who consumed whole wheat products over long periods showed considerably more weight loss than the others subjects.
Improvesbodymetabolism: Saturated and trans fats increase the chances of cardiovascular diseases, while omega-3 fats decrease cardiovascular disease risk. Whole grains like wheat are immensely effective on patients with metabolic disorders. Common types of metabolic syndromes include visceral obesity, also known as the “pear shaped” body, high triglycerides, low levels of protective HDL cholesterol, and high blood pressure. Wheat protects against all of these conditions. Research has shown that foods made from refined grains not only tend to increase weight but they also increase the hazards of insulin resistance. Doctors recommend eating whole wheat bread and other fiber-rich foods. The majority of fiber works to help the digestive process in the body and improve the overall metabolism. Having a whole wheat diet is probably the most effective, quick, and enjoyable way to reduce metabolic syndrome, but also to stay slim and healthy throughout your life.
To PreventsType 2 Diabetes: Wheat is rich in magnesium, which is a mineral that acts as a co-factor for more than 300 enzymes. These enzymes are involved in the body’s functional use of insulin and glucose secretion. The FDA permits foods that contain whole grain by at least 51% weight and are also low in saturated fat and cholesterol, which means a lower risk of coronary ailments and certain types of cancer. Moreover, regular consumption of whole grain wheat promotes healthy blood sugar control. People who suffer from diabetes are able to keep their sugar levels under control by replacing rice with wheat in their diet.
To ReducesChronicInflammation: The betaine content of wheat is what aids in the prevention of chronic inflammation. Betaine is usually found in whole wheat, beets and spinach. Inflammation is a key constituent in most types of rheumatic pains and also some rheumatic diseases. Thus, it is a good idea to eat a healthy amount of whole wheat food products that will actively reduce inflammation. Consumption of betaine affects a number of aspects in our body chemistry that assures a lower risk of chronic inflammation and other ailments like osteoporosis, heart disease, Alzheimer’s disease, cognitive decline, and type-2 diabetes.
To PreventsGallstones: In various surveys by the American Journal of Gastroenterology, it has been proven that breads and cereals made from whole wheat help women to avoid gallstones. Since whole wheat is rich in insoluble fiber, it assures a quick and smooth intestinal transit time and lowers the secretion of bile acids. Excessive bile acids are a major cause of gallstone formation. Moreover, a high intake of wheat increases insulin sensitivity and thereby lowers triglycerides or fat in the blood. Besides wheat, you also get insoluble fiber from the edible skins of fruits and certain vegetables like cucumbers, tomatoes and squash, berries,apples, and pears. Beans also provide both insoluble and soluble fiber.
WholeGrainWheatAssures a HealthyLifestyle: Wheat is the most popular and easily available bulk laxative. Three cups of wheat consumption per day is enough for an individual to live a long, healthy and disease-free life. When you maintain a fiber-rich diet comprised of wheat breads and cereals that are high in bran, you can be confident that problems such as pain, flatulence, nausea, constipation, and distension will be alleviated in no time. Diverticulitis often occurs due to inflammation and lower intestinal pains. This can also lead to chronic constipation and unnecessary straining, which can result in a sac or a pouch in the wall of the colon. Such cases can be easily dealt with naturally by keeping up with a fiber-rich diet and including whole grain wheat on a regular basis.
TO Promotes Women’s Gastrointestinal Health: Benefits of wheat bran are bountiful, and promoting overall women’s health is yet another important role of this cereal variety. Wheat acts as an anti-carcinogenic agent, particularly in women. Wheat bran enhances the metabolic rate of estrogen, which often leads to breast cancer if left at an excessive level. In one survey of pre-menopausal women in the age group of twenty to fifty, they ate three to four high-fiber muffins per day made from wheat, and they showed reduced blood estrogen levels by 17% in only 2 months. The other group of women eating corn bran did not show this result.
Wheat contains contain lignans, which are phytonutrients acting as hormone-like substances. The lignans often occupy the hormone receptors of our body, thereby alleviating certain risk factors for breast cancer. This effectively checks the high circulating levels of estrogen. Wheat increases the metabolic rate of estrogen production and protects women against this key factor of cancer. Wheat bran considerably reduces bile acid secretion and bacterial enzymes in the stool, thereby cutting down chances of colon cancer. If you include bread, pasta, and bran cereals in your daily diet, these ailments will be avoided.
Protective against Breast Cancer: Research at the UK Women’s Cohort Study found that a fiber-rich diet is extremely important for women to keep breast cancer at bay. Foods from whole grains like wheat and fruits provide significant safeguards for pre-menopausal women against breast cancer. Studies say that around 30 grams of wheat consumed daily is enough for women to reduce the risks of breast cancer. Reports say that pre-menopausal women who have consumed wheat had a 41% reduced risk of breast cancer in comparison to others who ate other forms of fiber.
To Prevents Childhood Asthma: The American Lung Association says that around 20 million Americans experience some form of asthma. Studies have stated that whole grains and fish in the diet can lower the chances of childhood asthma to a great extent. The International Study on Allergy and Asthma in Childhood proved through numerous studies that a wheat-based diet has the capacity to lower chances of developing asthma by almost 50%. During the survey, the wheat diet was increased considerably and the mothers were given special diets high in fish and whole grains; this showed an almost 66% reduction in the possibility of becoming asthmatic.
Bronchial hyper-responsiveness is the key factor that encourages asthma. This condition is characterized by the narrowing of the airways and increased sensitivity. In many surveys, it has been seen that children who eat wheat and fish in high amounts do not suffer from such ailments. The magnesium and vitamin E provided by wheat also contributes in reducing the problem of asthma. However, in some cases, wheat consumption may be harmful for asthma patients, since wheat also happens to be a food allergen closely linked with asthma. Consult a doctor who can give you a complete examination and diagnosis of possible allergies you may have.
To Protects against Coronary Diseases: Plant lignans, a type of phytonutrient, is abundant in whole wheat. These lignans are converted by responsive flora in the human intestines into mammalian lignans. One of these lignans is called enterolactone, which protects against breast and other hormone-dependent cancers, as well as heart disease. Wheat is not the only source of lignans; nuts, seeds and berries are also rich sources of plant lignans, as well as various other vegetables, fruits, and beverages like coffee, tea and wine. A Danish journal published in a recent article that women eating the most whole grains were found to have considerably higher blood levels of this defensive lignan.
Improves Cardiovascular Systemin Postmenopausal Women: Whole wheat is supposed to be a primary element in the diet of a post-menopausal woman so as to avoid any kind of cardiovascular problems. Daily intake of this whole grain cereal is the best way to avoid such ailments. Doctors prescribe a high wheat intake diet for women who are dealing with conditions like high blood pressure, high cholesterol, or other signs ofcardiovascular syndromes. A survey has concluded that this kind of diet slows down the progression ofatherosclerosis, which is the building of plaque in the arteries and blood vessels, as well as reducing the frequency of heart attacks and strokes.
To Prevents Heart Attack: In the United States, heart failure is the prime cause of hospitalization and death of elderly people. The medicinal drugs have been successful in certain cases, but natural remedies work much faster and with less of an impact on the rest of the body’s systems. Hospitals use ACE inhibitors and beta-blockers, but the long-term effects are not yet clear. Whole grain products and dietary fiber have been shown to considerably reduce blood pressure levels, thereby checking the possibility of a heart attack. Of course, confounding factors like age, alcohol consumption, smoking exercise and proper nutrition are equally important. Ample vitamins, vegetables and fruits are extremely important in such cases as well. The start of your day can be both healthy and tasty with a daily bowl of whole grain cereal. There are various other forms in which you can serve wheat like bread, puddings and a variety of baked goods.
The health benefits of wheat are no longer unknown, and people all over the world have experienced them by including wheat in their daily diet. This “health food” reputation is due to the important B vitamins, such as thiamin, folate, and vitamin B6, and the minerals magnesium, zinc, and manganese content. Wheat can be easily integrated into cakes, burritos, brownies, waffles, bread, muffins, patties and pancakes or simply sprinkled over your favorite cereal or yogurt.
1.2 AIM AND OBECTIVES OF THE STUDY
The aim of the study is to analyze data on yield of wheat in order to achieve the following objectives.
- To find out which of the factors, population pressure and fertilizer rate has any effect on the yield of wheat.
- To find out which factor combination produce the best yield for wheat
- To recommend this best factor combination to farmers
1.3 SIGNIFICACE OF THE STUDY
The study will identify which of the factor combinations (population pressure and fertilizer rates) produces the best yield for wheat
1.4 SCOPE OF STUDY
The study covers only two factors: population pressure, in three different levels (30kg/ha 100kg/ha 120kg/ha) and fertilizer rates in three different levels (80kg N/ha, 100kgN/ha, 120N/ha). Therefore, the result is tenable within this constraint and applicable to area with same climate and soil type as in Maiduguri.
1.5 PROBLEM OF DATA COLLECTION
There was no serious problem in the data collection because the data was a secondary data.
1.6 METHOD OF ANALYSIS
The factorial experiment implemented on a randomized complete block design (RCBD) will be analyzed using SPSS,
1.7 DEFINITION OF TERM
Like in most fields of human endeavour, experimental design has its own associated terminologies which need brief and careful explanations as to make this research work useful/understandable by a wider range or students and non-statistics based researchers alike.
- i. EXPERIMENT
An experiment is a carefully planned investigation done to explain new facts or confirm or deny findings or earlier researches.
- ii. EXPERIMENTAL UNITS
Experimental units refer to the group of materials or objects on which the experiment is conducted. It is the smallest unit of material to which a singleapplication of a treatment is made (Alika 1997).
Cochran (1958) defined it is as the smallest division of the experimental material that any two units may receive different treatments in the actual experiment.
- iii. EXPERIMENT DESIGN
A design experiment is a test or series of tests in which purposeful changes are made to input variables of a process or system so that we may observe and identify the reasons for changes in the output response (Montgomery 1991).
- iv. EXPERIMENTAL ERROR
It is the remainder error unaccounted for by the known sources of variation. it measures the variability among the experimental units that are treated alike. Experimental error is not synonymous with experimental mistakes.
- v. TREATMENTS
Treatments are the procedure whose effect is being evaluated and compared with one and several others. It can also be seen as the combination of all levels of all factors in all experiment (Osemwenkhae 2007)
- vi. FACTORS
Factors are other variables in an experiment under the control of the outcome (response) of the experiment and whose effect on outcome is of importance or interest.
- vii. LEVEL OF FACTORS
The level of factors refer to any value taken by the factor in an experiment; it refers to the degree or intensity of a factor. Any factor may be presented in one or more of several levels, including a zero level.
- viii. DEGREE OF FREEDOM
Degree of freedom is measured as the sample size less the number of restrictions imposed on the calculation (Kelly et al., 1992)
- ix. TEST OF HYPOTHESIS
The whole idea behind the conducting of any experiment is to test one thing or the other or to prove or disprove some facts. Hypothesis testing involves a preconceived theory concerning the population characteristics (e.g. variance , mean x etc.) of interest.
In hypothesis testing, we have two stated hypothesis, viz
- Null hypothesis ( i.e. hypothesis of no difference
- Alternative hypothesis () i.e. hypothesis of existence of difference
A test statistics (formula) is used to test the validity of the null hypothesis. These hypotheses ( and ) must be stated at the one set of the experiment.
- x. INTERACTIONS
Interactions refers to variables in the treatment which may interact with each other it may make a difference whether a variable is used by itself, with another, or with different levels or degrees of another.
- xi. ANALYSIS OF VARIANCE
The analysis of variance (ANOVA) is a statistical procedure developed by F.A Fisher. It refers to the theory and procedures for analysing the values of an experiment.
The general purpose of ANOVA is to determine which factors of an experiment have noteworthy effects on the values and to provides qualitative information about the relative importance of difference factors and there levels. (Lee, 1935)
The analysis of variance divides the total variability in a measured responses into its causal components which is then tested for its degree of contribution to the overall contribution relatively.
The result of the analysis of variance is presented is an ANOVA table and used to decides whether or not to accept the null hypothesis depending on the pre-decided level of significances, (p or ).
