eChapters

4.1. Deficiency symptoms in different plant parts

Nutrients are important for growth and productivity of crops. Apart from the N, P, K, Ca, Mg and S, micronutrients such as Zn, Fe, Cu, B, Mo, Mn, Cl, etc. are also necessary for maintaining normal health and metabolism of plants. However, nutrient deficiency can lead to poor and stunted growth of plants resulting in poor yield performances. The depletion of nutrients from the soil is increasing due to adoption of modern agricultural technology through intensive and extensive cultivation of high yielding varieties. Nutrient deficiencies are very common in horticultural crops rather than in field crops.

Identification of nutrient deficiencies in crop plants through visual symptom is the cheapest diagnostic technique. When a nutrient element insufficiency occurs, below the critical level, visual symptoms may or may not appear, although normal plant development will be slowed. When visual symptoms occur, such symptoms can frequently be used to identify the source of the insufficiency.

2.1. GENERAL DESCRIPTION

Forests covered only 31 per cent of the land in the world in 2011, while land used for agriculture, (cultivable land, perennial crops and pastures), covered 38 per cent (FAO 2011). In the history of humankind, agriculture is a recent invention (Mazoyer and Roudart, 2005). With the transition from the huntergatherer lifestyle to one of agriculture during the Neolithic Revolution, farmers quickly expanded their activity into forest areas. They developed shifting cultivation, an agricultural practice with temporal rotations in forest ecosystems. Shifting cultivation still exists today in tropical regions and is the livelihood basis for hundreds of millions of people (Mertz et al., 2009). The range in the population estimate is extremely wide, because of difficulties in counting smallholders spread out under the tree canopy at the margins of tropical forests, as also due to confusion that exists in differentiating shifting cultivators from other farmers involved in small-scale agriculture (Thrupp et al., 1997).

Introduction

Any work condition revolves around three main components - the man, machine and environment. 'Man'-is represented by the worker who is either the controller or the executor of an action. Therefore the work output depends on how efficiently the workers are performing. In this context, the health of the worker is of utmost importance. It is one of the prime supporting pillars of productivity. If the health condition declines, efficiency is reduced and productivity suffers. Work involves a variety of physical and cognitive activities performed to achieve a desired or specified productivity. It may include a single individual or a small or large group of people as the worker. It is characterized by a specified duration, specific speed or work pace and a required amount of effort. The performance and efficiency expected from the workers have a direct bearing on the work process or work tool and the work environment. All these stress the bodily systems and affect the health of the worker. The stress could be classified as physiological stress and psychological stress Occupational health deals with the study and maintenance of physical, mental and social well-being of workers in the workplace (WHO, 1957). Occupational Physiology and Ergonomics are related branches of Occupational health that are in particular concerned with the study and maintenance of health and well-being during work.

1.1. General Discussion of Milk

“The cow is the foster mother of the human race. From the days of the ancient Hindoo to this time have the thoughts of men turned to this kindly and beneficent creature as one of the chief sustaining forces of human life”.

William Dempster Hoard (1836-1918)
Former Governor, State of Wisconsin, USA (1889-1891)
Founder of Hoard’s Dairyman (1885)

The oldest written records of the human race are in Sanskrit and are preserved in India. At the time these records began, about 6,000 years ago, milk had already become an important article of food. In fact, so important was the cow to these early people of South and Central Asia that wealth was measured in numbers of cattle, and the cow was in time made a sacred animal and is still so considered in India.

According to the best authorities, the domestication of cattle must have occurred somewhere between 6,000 and 10,000 years ago. The cow was worshipped in Babylonia, and in Egypt about 20,000 B.C. Over fifty references to cows and milk are found in Old Testament and the Promised Land was described as “a land flowing with milk and honey”.

Milk is the only food of the young mammal during the first period of its life. The substances in milk provide more energy and the building materials necessary for growth. Milk also contains antibodies which protect the young mammal against infection. A calf needs about 1000 litres of milk for growth, and that is the quantity which the primitive cow produces for each calf. There has been an enormous changes since man took the cow into his service. Selective breeding has resulted in dairy cows which yield more than 5,000 litres of milk per calf, i.e. five times as much as the primitive cow. Some cows can yield 10,000 litres or more.

Agricultural finance generally means studying, examining and analyzing the financial aspects pertaining to farm business, which is the core sector of India. The financial aspects include money matters relating to production of agricultural products and their disposal.

What is a Farming System?
A farming system is a complex and interconnected set of components, activities, and interactions that occur on a farm. It’s a holistic view of agriculture that considers not only the crops grown but also the livestock raised, the resources used, the environment, and the socio-economic factors that influence the farmer’s decisions. It aims to optimize productivity and sustainability. A farming system is a population of individual farm systems that have broadly similar resource endowments, enterprise patterns, household livelihoods, constraints, and for whom similar development strategies and interventions would be appropriate. It is a complex interwoven mesh of soil, plant, animal, people and other resources surrounding by a distinct boundary jointly managed by farm households. A farming system refers to a complex, interrelated matrix of soil, water, crops, animals, labor, and other resources managed by farm households to increase productivity and ensure food security. It goes beyond crop production alone—it is a holistic concept that includes all on-farm and off-farm activities contributing to a family’s livelihood. Farming-based livelihood systems emphasize the role of agriculture and allied sectors in supporting rural life and sustainability.
• It considers the interactions between different components of the farm (crops, livestock, soil, water, etc.) and how they are managed by the farm household.
• The aim is to optimize resource use, increase productivity, and improve the sustainability of agricultural production.

What are Pesticides?

Pesticides are essential tools for controlling harmful and invasive pests in agriculture, forestry, and the landscape. Pesticides are any substances used to prevent, eliminate, repel, attract, or diminish pest organisms. Pesticides that are well-known include insecticides, herbicides, fungicides, and rodenticides. Growth regulators, plant defoliants, surface disinfectants, and several swimming pool chemicals are among the others. Insecticides include pesticides (effective against insects), herbicides (effective against certain plants), rodenticides (effective against rats), bactericides (effective against bacteria), fungicides (effective against fungi) and larvicides (effective against larvae).

Disease in plants defined as the series of invisible and visible responses of plant cells and tissues to a pathogenic organism or environmental factor that result in adverse changes in the form, function, or integrity of the plant and may lead to partial impairment or death of plant parts or of the entire plant.

A pesticide is any material intended to prevent, destroy, repel, or mitigate any pest, which is defined as a living organism that occurs where it is not wanted or that causes damage to crops, humans, or other animals. There are many different types of pesticides, each is meant to be effective against specific pests. The term “-cide” comes from the Latin word “to kill.”

6.1 general description

Between 13,000 and 3,000 BC, Neolithic period, mountain people in Asia, Africa, and Latin America have practiced shifting cultivation (Mazoyer and Roudart 2006). A cultivation phase, consisting of removing forest and crop production for 1 to 3 years, is followed by a fallow phase, in which agriculture is discontinued to allow soil nutrients to recoup (Conklin 1961). Conklin (1961) distinguished between total and partial shifting cultivation. Pioneer shifting cultivation, in which primary or apex forest is cleared annually, and replaced by shifting cultivation, which entails clearing mostly secondary forests, are both essential forms of cultivation that are primarily practised for farmers' subsistence. Partial shifting cultivation, on the other hand, is done as a supplemental or temporary activity (Conklin 1961). Throughout history, indigenous peoples have used fire to manage their land and natural resources. Pastoralists and hunters-gatherers in Africa's savannas, for example, have used fire to preserve the ecosystem's productivity for livestock and game for millennia (McClanahan and Young 1996). In pre-colonial times, indigenous peoples in North America also significantly altered the landscape, establishing and preserving pastures and open forest savannas through regulated burning (Pyne 1982, cited in: Schneider 2000).

Herbicides degrade over time. The persists of herbicides is dependent on several factors including light, temperature, and substrate moisture. Several processes are responsible for herbicide degradation and include the following:

    1.    Photodegradation: The decomposition of herbicides caused by duration or intensity of sunlight is called as Photodegradation. Photodegradation occurs when ultraviolet (UV) light breaks chemical bonds of the herbicide active ingredient. Secondary molecules resulting from the cleavage of the parent molecule are generally less effective in providing weed control. Herbicides such as Monuron, Trifluralin, PCP, Chloramben etc are prone to photodegradation. So these herbicides should be applied in evening or incorporated in to the soil just after application in order of avoiding photodegradation.

Land, a non-renewable resource, is central to all primary production systems. Over the years, the country’s landmass has suffered from different types of degradations. Land degradation can be defined as lowering of land productivity due to the deterioration of land’s physical, chemical and biological condition. Physical land degradation is due to water erosion, wind erosion, compaction, crusting and water logging and chemical degradation is due to the processes of salinization, alkalization, acidification and nutrient depletion. Biological degradation is due to the reduction of soil biota and organic matter, degradation of vegetation and impairment of activities of microflora and fauna. Land degradation is steadily increasing due to the growing pressure on land and unsustainable land use. Land degradation and the associated loss of soil productivity and quality is of great concern both from food production and environmental conservation point of view. An ever-increasing population created enormous pressure on land resources.

Flowers and various parts of the plant have been used for decoration and to commemorate various religious, festive, matrimonial and social gathering events in day to day life. The main drawback of fresh flowers and foliage is being highly perishable and delicate which cannot retain their beauty for longer durations. Moreover fresh flowers are not available round the year which can be overcome by the dehydration and drying techniques. Since ancient times, in Egyptian pyramids, fragrant dried flowers and herb garlands were encased along with mummified bodies. Japanese people created “Oshibana”, the “preserved flower art” of enduring designs to retain the exquisite beauty of the living plants centuries ago.

Later on, this craft making technique spread from Japanese to Victorian England because of their beautiful long lasting appearance. During middle ages monks dried flowers, foliage, and herbs for use in decorative motifs or for colouring their handprinted books.

Dried flower arrangements have been popular in Europe for centuries, and as early as 1700 AD, colonial Americans used dried flowers to brighten their homes, especially during the dark winter months.

Earlier botanists practiced dried flowers in the form of herbarium for the purpose of identification of various plant species. Though drying of flower was well known even in the past but for the first time the flowers were dried commercially in Germany (Sankari and Anand, 2014).

INTRODUCTION

Drying or dehydration is defined as the removal of moisture from its initial level to a level which renders food materials safe for subsequent storage. It is a simultaneous heat and mass transfer operation in which heat is supplied externally to evaporate moisture and air is forced through the bed to carry away the moisture. Drying is the oldest technique to preserve food materials. Advantages of drying include reduction in water activity, enhancement of shelf life, maintenance of flavor and nutritive value, and reduction in packaging and transportation costs. When the water activity of the dried product is reduced to below 0.6, most microorganisms do not grow and the rates of other deteriorative reactions are substantially reduced.

Materials Required

Dehydrator, balance, thermometer, sulphur dioxide, blanching pan, fruits / vegetables, polythene or aluminium bags.

Procedure

    1.    Select sound fruits or vegetables 
    2.    Record their initial weight and wash them properly in plain water to remove any dirt or extraneous matter. 
    3.    Peel with stainless steel knife (as the case may be) and cut into thin uniform pieces or slices of  0.2-0.5 mm thickness
    4.    Blanch the slices in boiling water for 1-2 min. to inactivate the enzymes followed by immediate cooling.
    5.    Treat the slices with sulphur (sulphuring or sulphiting) in order to prevent darkening of the product during drying. 
    6.    Dry the slices in a mechanical air dehydrator at about 55 + 5oC temperature.
    7.    Record the weight of the product after every 2 hr till it becomes (almost) constant i.e. when there no more (significant) loss of moisture from the product.
    8.    Pack the product in ploythene or aluminium laminated pouches and seal them air tight. 
    9.    If it is to be converted into powder, the dried product can be ground in a grinder before packing.
    10.    Label the packages and store them in a cool dry place.
    11.    Plot the drying rate curve of the product on a graph paper and analyse it.
    12.    Record the initial and final moisture content of the product (as discussed in Exercise No. 19). 

Drying and dehydration are interrelated terms. Drying generally refers to the method of removal of moisture from the food under natural conditions such as sunlight and wind for example open sun drying, shade drying etc. Whereas, dehydration refers to a process of removal of moisture by application of artificial heat under controlled conditions of temperature and airflow. In this case single layer of fruit and vegetables, either whole or sliced after primary pretreatments is spread on trays which are placed inside the dehydrator or in the open sun for drying. In the dehydrator, the initial temperature is generally kept at 43oC which is then gradually increased to 66-71oC for fruits and 60- 66oC for vegetables. Dried grapes (raisins and monucca), apricots, dates, apple rings/cubes, Morchella (Guchhi), bael, aonla, fig, green peas, cauliflower, cabbage, onion, garlic etc are commercial products prepared by using drying.
Procedure for drying: Drying generally involves three stages: pre-drying treatments or pre-treatments, drying of commodity and post-drying operations such as handling, packaging and storage. The flow sheet for drying of fruit and vegetables is shown in Figure 1 and details of pretreatments for drying fruits and vegetables are shown in Table 1&2 respectively.

Drying is the oldest known method of preserving food. Drying or dehydration is removal of majority of water contained in fruit or vegetable. Although preservation is the primary reason for dehydration, it also lowers cost of packaging, storing and transportation by reducing both weight and volume of final product. In addition, dried foods add variety to our diets. In the process of drying, sufficient moisture is removed to protect product  from  spoilage. Processing should be done in such a way that food value, natural flavour and characteristic cooking quality of fresh material are retained after drying.

48.1. Aim

To conduct practical on drying of fruits

48.2. Theory

Drying generally refers to the method of removal of moisture from the food under natural condition such as sunlight and wind for example open sun drying, shade drying etc. Dehydration refers to a process of removal of moisture by application of artificial heat under controlled conditions of temperatures humidity and air flow. It also represents drying of agricultural commodity to dry state. For drying, single thin layer of fruit and vegetables, either whole or sliced after primary pre-treatments is spread on the trays which are then placed inside the dehydrator or in the open sun for drying. In the dehydrator initial temperature is generally kept at 43oC which is then gradually increased to 66-71oC for fruits.

49.1. Aim

To perform practical on drying/dehydration of different vegetables.

49.2. Theory

Drying refers to the method of removal of moisture content from the food to a level at which the activities of food spoilage and food poisoning micro-organism are inhibited. Therefore, reduction in water activity of the food is the main principal of preservation by drying. In the dehydrator initial temperature is generally kept at 43oC which is then gradually increased to 60-66oC for vegetables. The product shall be prepared from wholesome vegetables free from blight, insect infestation and fungal discoloration. Only edible portion of the vegetables shall be used and it shall be free from stalks, peels, stems, and extraneous matter. The dried/dehydrated vegetable may contain permitted preservative. The finished product shall be of good edible quality and shall reasonably reconstitute to its original shape and quality on boiling for 15 minutes to an hour. The finished product shall be free from visible mould, insect or larvae. Kind of dry vegetable shall be declared on the label. Acid insoluble ash shall not be more than 0.5%.

1 What percentage of body weight is intracellular water

a) 60 b) 40

c) 20 d) 15