eChapters

The term weed can be described in many ways. In general, it is said that weed is a plant, which is not sown by the farmers or which is out of place. Weed is defined as the unwanted, undesirable plant, growing out of its proper place, which interferes with the utilization of natural resources, is prolific, persistent, competitive, harmful and even poisonous in nature and can grow in adverse climatic conditions.There are more than 30,000 species of weeds distributed world over, out of which 18,000 are noxious and cause serious losses. Around 250 species are causing serious economic losses. Weeds in orchards reduce crop yields by competing for moisture, nutrients, light and space. They also act as a host for insect pests and diseases. When they become large, they interfere with orchard operations as well as water bodies. There are some weeds, which are parasitic partially or completely on the host tree e.g. striga and loranthus, in mango.

Indian tea has a global reach being the second largest tea producer in the world. Indian tea is one of the finest in the world. Darjeeling tea is the first product to get a geographical indicator tag in India. 83 % of the tea produced in India is from Assam and West Bengal and 17% from the south Indian states of Kerala, Karnataka and Tamilnadu. Weeds are a major problem in tea gardens.

Weed flora

Drymaria cordata, Bidens pilosa,, Cynodon dactylon, Panicum repens, Celosia argentea, Ageratum conyzoides, Centella asiatica, Borreria hispida, Oxalis latifolia, Mikania micrantha, Paspalam conjugatum,

Rice is the primary food source for half of the Asian population. Nearly 2,000 million in this region obtain 60 to 70 per cent of their calories from rice and its products. Considering the importance of the crop, United Nations General Assembly declared 2004 as the “International Year of Rice” (IYR). In India, the crop covers one-fourth of the total cropped area. About half of the Indian population use rice as their staple food.

Rice based cropping systems are not only important for food security but also for maintaing an ecological balance. Low land rice fields conserve water and prevent runoff .They preserve the sustainability of the ecosystem.

Weed is a plant that is growing in the wrong place. Weeds have many mechanisms and characteristics that enable them to compete, having thick waxy cuticle leaves that can be resistant to some chemicals, fast reproduction methods, the ability to reseed in 6 week cycles and deep tap roots enabling the weed to survive in compacted dry ground conditions.

There are many reasons to control weeds in annuals/biennial and perennial ornamentals. Weeds compete with the plants by absorbing essential nutrients and water, or by blocking light or air circulation. Weeds dramatic reduce the growth of the plants. The greatest damage is often done when the weeds and ornamental plants are small. Weeds also interfere with harvesting by physically hindering. They lower flower quality further by harbouring insects, such as whiteflies, thrips mites, slugs, snails and/or diseases.

Growing under optimal conditions for the flower will reduce the ability of weeds to compete against the crop. Controlling humidity/ventilation, water, light, pH, nutrients and temperature all figure prominently in providing flower optimal conditions. A plant health strategy to greenhouse weed control contains three principal elements, prevention/sanitation, evaluation of water quality and using all controls available physical, cultural and chemical. Prevention and sanitation can include the use of mulches in orchidhouse weed control. Rice hulls, perlite, pumice, corn gluten meal bark, Penn Mulch - pelletized recycled paper and human hair have all been used for this purpose. Prevention also includes, eliminating air borne weed seeds from entering the greenhouse by screening vents and other openings and preventing perennial weeds from growing under foundations. A 1-3 meter weed free zone should be maintained immediately adjacent to the greenhouse.

INTRODUCTION

Control of weeds below economic threshold level in potato crop is a substantial component of crop management strategy for achieving optimum productivity. In our country, potatoes are raised eitherin assured irrigation or as rainfedcrop with comparatively heavy doses of fertilizers. Therefore, weedsarebound to become menaceduringactive cropgrowth period of this cropand theseundesired plants needs to be controlled in early stages of crop growth by adopting several techniques. Current scenario of crop production is different from past due to manyreasons. Farm holdings are becoming smaller day-by-day and majority of potato growers are small and marginal farmers. They have limitedcapacity for purchase of inputs and farm machines. They need economical, efficient and easier to adopt weed control technologies.Farm labour is also costly nowin many regions as they are migrating towards cities and industrial townships. This scenariobecomes more complex as weeds would be major challenge due to global warming, which is slowly changingclimatesof potato growingregions in India.Theconcern forenvironmentalissuesemphasizeuponadoptingsystems and integrated approach for managing weeds in such away that thesedo not reducethe potato and system productivity (CPRI, 2014).

Objectives

1. To study the weeds and its control.
2. To study the herbicides, their types, timing and methods of application.

Weed: A wild plant growing where it is not wanted and in competition with cultivated plants.

Or

Weed is such undesirable plant grown in association with crop which snatches major parts of nutrients, water, light, place and CO₂ available to the crop.

Due to tough competition crop suffers adversely and the production is reduced.

Most of us consider weeds to be the troublesome, competitive, aggressive, undesirable, unsightly elements of the plant world. We hate weeds since desirable plants cultivated by us are deprived of food, water, sunlight and space by these plants. They can easily colonize an area and thrive even under non-ideal conditions of growth and may affect human welfare adversely. It is perhaps due to this that the saying, when weeds win all the people lose, has come into existence.

The terminology committee of the Weed Society of America gives the simple definition of weed as a plant growing where it is not desired. King (1974) in his book Weeds of the World observed that ‘‘a plant classed as a weed in one region where it has few, if any, uses may when growing in another region, possess some very valuable uses, or in few cases may actually be cultivated’’. For instance, Bermuda grass (Cynodon dactylon) is a highly troublesome weed in crop fields, but in village pastures, it is a much sought for forage grass. Quack grass (Agropyron repens) is a very good soil binding grass on erodable non-crop lands but it is a serious weed when it infests crop fields and orchards. Campbell (1923) considered weeds as ‘honest, independent competitors for food materials in the struggle for existence’. He pointed out that the term, weed has developed in the minds of people not according to specific qualities or by a definite concept in the mind of man, but by human caprice, e.g., corn is a cultivated crop, hence, desirable plant in a corn field. However, if a corn plant grows in a Soya bean field, it is considered a weed by the Soyabean farmer. Sometimes, two persons may differ about the weedy nature of a plant at the same place and time, e.g., water hyacinth (Eichhornia crassipes) is a weed for fisherman but it is a plant of aesthetic value for a city dweller.

Thus, a corollary to the above definitions of weed is that weeds are those plants, which grow out of their place, interfere with the utilization of natural resources, prolific, persistent, resistant, competitive, harmful and even poisonous in nature and can grow under adverse conditions.

Weed management practices are evaluated for its efficiency in terms of effective control of weeds and economics of control measures through various indices under sole crop situation as well as intercrop situation.

6.1. Indices for Sole Crop Situation

The absolute effect of particular method or a chemical in reducing the weed competitions and increasing the crop productivity are measured effectively by various indices. The comparisons of weed control methods are usually based on the yield, weed population and weed dry matter from the control as well as treated plots.

With Judicious Use of Herbicides

Herbicides are the chemicals used for killing or suppressing the growth of weed plants from field / horticulture / plantation crops as well as non-cropped areas/ water bodies etc. The herbicide is said to be an ideal herbicide when it is very safe to the crop on which it is applied and on the other hand, it must control all associated weeds effectively. Also, ideal herbicides should leave no residual effects on the succeeding crop(s). Herbicides are of two types i.e.

1. Selective herbicides and
2. Non-selective herbicides.

A selective herbicide is that which is very safe to crop plants but unsafe to weed plants e.g. atrazine in maize, clodinafop in wheat etc. On the other hand, non-selective herbicides are those which kill all green plants including crop and weed plants which come in their contact e.g. paraquat and glufosinate ammonium.

Onion is highly vulnerable to weed competition because of its slow early growth, shallow roots, narrow upright leaves and limited canopy development. Weeds compete for light, water, nutrients and space while also harbouring pests and pathogens. Severe infestation during the critical competition period can cause substantial yield reduction. This chapter describes major onion weeds and evaluates cultural, physical, mechanical, biological and chemical control methods. Timely planting, suitable spacing, mulching, raised beds, manual weeding, mechanical tools, herbicides and biological agents are discussed. Integrated Weed Management is recommended as a smart approach combining complementary methods to improve weed control, protect soil health and sustain onion productivity.

Weed management in natural farming emphasizes natural, chemical-free methods that align with ecological principles. Instead of using herbicides or synthetic chemicals, natural farming promotes approaches that maintain biodiversity, improve soil health, and reduce weed pressure through various cultural, mechanical, and biological methods.
Here are key strategies for weed management in natural farming:
1. Mulching
Mulching is an agricultural and horticultural practice in which organic or inorganic materials are spread over the soil surface to protect and improve soil quality. In natural farming, mulching plays a key role by fostering a healthier ecosystem for plants without synthetic inputs.
Types of Mulch
Mulches are broadly categorized into organic and inorganic types:
• Organic mulch includes materials such as straw, leaves, grass clippings, crop residues, compost, wood chips, and sawdust. These materials decompose over time, enriching the soil with organic matter and nutrients.
• Inorganic mulch consists of materials like plastic sheeting, landscape fabric, and gravel. While these do not decompose, they effectively suppress weeds and retain moisture but do not improve soil fertility.

Weed

Definition: “Weed is an unwanted plant growing where it is not desired.” – Jethro Tull

Commonly noticed weed species in fruit orchard:

• There are more than 30,000 species of weeds distributed world over, out of which 18,000 are noxious and cause serious losses.
• Around 250 species are causing serious economic losses.
• Monocot weeds (Narrow leaf/Grasses): Cyprus, Cynodon, Poagrass, Rye grass, Quackgrass etc.
• Dicot weeds (Broad leaf weeds): Dandelion, Chenopodium spp., Parthenium, Solanum, Euphrobia spp., Ground ivy etc

Symbolic to its nomenclature, ’PULSE’ (P = people, U = umbrella, L = livestock, S = soil and E = energy) is a superb group of agricultural crops extending an energy umbrella to people (as a major source of dietary protein), livestock (as a green nutritious fodder and feed) and soil (as a builder and restorer of soil fertility through biological N₂ fixation). On account of these qualities, pulses have occupied a unique position in the Indian farming system. Crop diversification with greater inclusion of legumes is essential to alleviate declining factor productivity, input use efficiency and increasing cost of cultivation for realizing sustainable use of natural resources. Pulses are increasingly becoming a component of the intensive cropping systems as intercrop, substitute crop or catch crop. In upland situations, pulses play an important role as intercrops and ensure more income and efficient use of resources. While analyzing the reasons of low productivity of pulses in various parts of the country, it is observed that non availability of high yielding disease resistant varieties, cultivation on marginal and sub-marginal lands under deficit moisture and fertility and poor pest management are the major constraints in realizing optimum yield potential.

13.1 INTRODUCTION

Weed is defined as an unwanted plant growing at a place where it is not desired. Weeds are unwanted and undeserved plants that interfere with the utilization of the land and water resources and thus adversely affect crop production and human welfare. Thus, a plant out of its place or a plant growing where it is not desired at that time is a weed. Weed has no species, but name was suggested as a useless and harmful plant that persistently grows where it is quite unwanted. According to Jethro Tull, the father of Weed Science, weed is defined as the unwanted, undesirable plant, growing out of their proper place, which interfere with the utilization of natural resources, prolific, persistent, competitive, harmful and even poisonous in nature and can grow in adverse climatic conditions. Of the total losses caused by pests, weeds have a major share (30%). They reduce the crop yield and decrease the quality of produce and hence reduce the market value of the turnout. Weeds are a major problem to horticultural production as they take advantage of their initial slow growth rate. Weeds reduce crop yield, lower their quality, act as alternate host of many pests/diseases and also have allelopathic effects on crops. Weeds also interfere with vital farm operations like weeding, fertilizer application, herbicide application and harvesting. Both annual and perennial weeds are common in their actions reducing the productivity of fruit trees. Weeds also provide shelter to various pathogens by becoming an alternate or collateral host of invaded crops by a number of fungal, bacterial and viral diseases.

The worst weeds found in the world are Cyperus rotundus, Cynodon dactylon, Echinochloa crusgalli, Echinochloa colona, Eleusine indica, Sorghum halepense, Imperata cylinderica, Eichhornia crassipes, Portulaca oleracia, Chenopodium album, Digitaria sanguinalis, Convolvulus arvensis, Avena fatua, Amaranthus hybridus, Amaranthus spinosus, Cyperus esculentus, Paspalum cojugatum, Rottboelia exaltata (Rana and Rana, 2016). All of these weeds are found in India. It has been reported that about 36-42% losses may occur due to inadequate management of weeds in apple (El- Metwally and Hafez, 2007). Therefore, management of weeds in all agro-ecosystems is crucial to sustain our crop productivity and to ensure the food security to the rapidly increasing population.

Site-specific weed control technologies practiced in precision farming are defined as machinery or equipment embedded with technologies that detect weeds growing in a crop and take action to maximise the chances of successfully controlling them taking into account predefined factors such as economics.Some of the commercial hardware and software developed for precision agriculture practices comprise tools for weed mapping and control software that adapts spraying to local weed occurrence. However, few farmers have adopted sitespecific weed management, although several studies have shown that weed occurrence and density varies significantly within a farm or a field. Site-specific weed control techniques have gained interest in the precision farming community over the years. Managing weeds on a subfield level requires measuring the varying density of weeds within a field. Decision models aid in the selection and adjustment of the treatments, depending on the weed infestation. The weed control can be done either with herbicides or mechanically. A site-specific herbicide application technology can save large amounts of herbicides. Mechanical weed control techniques adapting to the weed situation in the field are applicable to a wide spectrum of crops.

A system for the discrimination of different weed species and crops from images is done which generates weed maps automatically. Models for the yield effect of weeds are developed and applied in on-farm-research experimental setups. Economic weed thresholds are derived and used for an herbicide application with a patch sprayer.Herbicide use has not eliminated weed problems in agriculture and the need for manual weed removal is still an issue within specialty crop systems, particularly during the first several weeks of crop emergence when competition for resources is greatest.

Precision agriculture is a powerful technology with potentially important applications to weed management. However, growers should remember good agronomic practices, including preventing weed infestations, managing herbicides wisely to prevent resistance, and minimizing environmental impact associated with weed management. Weeds, and methods used to control weeds, can have negative economic and environmental impacts. With precision agriculture, growers can take advantage of the patchy nature of weeds by targeting management efforts only where they are needed instead of wasting expensive and potentially hazardous inputs where weeds are not present. Weeds are patchy because weed spread, survival, and reproduction are variable within a field and over time. Weed patches stay in about the same place from year to year, even though weed density within a patch may vary

Weed

Weed in orchards reduce crop yields by competing for moisture, nutrients, light and space. They also harbour insect pests and diseases. When they become large they interfere with orchard operations. Some of weeds climb on the trees and shade the foliage. There are some weeds which are parasitic partially or completely on the host tree e.g. Striga and loranthes on mango.

Different crops are grown in a field. Any plant growing in a place where it is not desired competing with the main crops, has to be weeded out and such plants are called ‘weed’.

Effect of weed menace The weeds

Reduce crop yield and production efficiency. It competes with the main economical crop for space, water and nutrients.

Reduce crop quality.

Hamper intercultural operations.

Reduce crop quality.

Obstruct the flow of water in the irrigation channels.

Exert allelopathic effect on crops.

Harbour insect and pests, which affect the main crop of interest.

Increase the cost of production.

Abstract
Legumes are an excellent group of fertility restorer crops which can be grown either as sole crop or as a component crop in the cropping system. As they are tolerant to drought condition, they can be grown throughout the year. The yield of legume crop is largely depending on pest, diseases and weeds. Among these weeds plays a major role as the weed seed bank inside the soil influence the weed population in the cropping season. Hence it is important to manage the weed seed bank for better productivity of legumes. Though legumes are short duration and fast growing crops, the germination percentage of weed seed bank will determine the final yield of legumes. There are many strategies to which the weed seed bank can be controlled to tolerable level before which the weed seed bank present in the soil has to estimate. Annual weed seed bank can be minimized by killing the weeds before they set seeds, harvest weeds, crop rotation, cover crops, inter cropping and ensiling. Weed seed bank depletion can be done by tillage, tricking the weed seeds, conditioning weed seeds, soil solarisation and herbicide application. Thus integrating various technologies may help in effective controlling of weed seeds to tolerable level thereby enhancing the yield of leguminous crops.
Keywords: Estimation of weed seed bank, legumes, tillage, yield, weed seed bank

Shifts or changes in the abundance and types of weeds within agricultural systems are common. These shifts can occur for a number of reasons and may result from cultural, mechanical, or chemical weed management strategies. The right combination of weeds and relying too heavily on any one practice is often the most common cause. Some of the concepts associated with weed species shifts are discussed below.

A weed shift is the change in the composition or relative frequencies of weeds in a weed population (all individuals of a single species in a defined area) or community (all plant populations in a defined area) in response to natural or human-made environmental changes in an agricultural system. Weed shifts occur when weed management practices do not control an entire weed community or population. Some species or biotypes are killed by (or susceptible to) the weed management practice, others are not affected by the management practice (tolerant or resistant), and still others do not encounter the management practice (dormant at application).

Those species that are not controlled can grow, reproduce, and increase in the community; resulting in a weed shift. Any cultural, physiological, biological, or chemical practice that modifies the growing environment without controlling all species equally can result in a weed shift. Weed shift may be due to introduction of new species or change in relative proportion of members of the existing community. Latter is the most common.

A. Species shift: Change in density of one or more species in field

B. Biotype shift: Change in density of biotypes within a species. These shifts often found noticed since biotypes typically are similar in appearance. Herbicide resistantbiotypes are the most frequently studied.

Weed monitoring is conducted to detect significant weed problems, rank them for relative severity and sort them by management type annuals, biennials, perennials, grasses and broadleaves. Weed monitoring provides information to tailor weed management efforts that reduce the impact of the weeds. The primary objective of weed survey and mapping is to accurately identify and delineate land with populations of unwanted plants. These surveys are conducted so that scientists and managers can predict those areas potentially subject to weed invasion; understand the biology of the invasion process and determine means by which weeds spread; develop, implement and evaluate weed management plans; assess the economic impact of weed invasion and increase public awareness, education and weed management efforts. Weed survey information is collected and compiled into maps showing the distribution and severity of infestation. Weed monitoring involves repetitive surveys to track weed populations over time. A standardized system of weed surveying and mapping is necessary to provide consistently reliable information that can be compared from year to year. Further, a standardized system allows weed survey data to be incorporated into a state wide weed survey database for the production of state wide noxious weed maps.

5.1 Weeding and Interculture Equipment

The aim of weeding and intercultivation operation is to provide best opportunity to crop to establish and grow vigorously up to time of maturity. The main objectives of weed control are to improve the soil conditions by reducing evaporation from the soil surface, improve infiltration of rain or surface water, and reduce runoff to maintain ridges or beds on which the crop is grown and to reduce competition of weeds for light, nutrients and water. Mechanical methods of weed control are simple and easily understood by farmers. The tools and implements for mechanical weed control are mostly manual and animal operated. Manual method is most effective but is slow. It is popular in regions where labour wages are low and labour is easily available during the season. The additional cost of weeding using implements is comparatively less than the gains due to extra yields obtained. First weeding operation is mostly done between and along the rows. Remaining operations are done mostly between the rows. Hand hoes are generally used for removing weeds between plants in a row.

19.1. Need for weeding

Weeding is the critical operation to be carried out to obtain a good crop. Weeds are plants which grow in places where they are not wanted. They grow in the fields competing with crops for water, soil nutrients, light and space and thus reduce crop yields. They also harbor insect pests and micro-organisms. Certain weeds release the inhibitors or poisonous substances into the soil which are harmful to plants, human beings and livessecks. They increase the expenditure on labour and equipment, render harvesting difficult and reduce the quality and marketability of agricultural produce. When grown in water channels, they block and or reduce the flow of water.

The weed seeds germinate earlier and grow faster than the crop plant. This phenomenon is more pronounced when coupled with favourable environment like fine soil tilth and the soil receiving adequate water and fertilizers. Weeds flower earlier and produce seeds profusely ahead of the crop. So, these seeds get mixed up with the harvested crop and are distributed to the next season or transported to other places along with the harvested produce.

An agricultural weeder is a tool designed to remove weeds from fields or gardens. It can be used manually or attached to machinery like tillers and power weeders. Weeding is necessary to eliminate unwanted plants that compete with crops, ensuring better growth and profitability. Effective weed management is crucial in crop production, as weeds can reduce yields by stealing nutrients and attracting harmful pests. In recent years, research has focused on non-chemical methods and environmentally friendly alternatives to herbicides for weed control. Mechanical weeding is often the most cost-effective solution. Tools like rotary weeders, mechanical hand weeders, and wetland weeders are generally effective, with wetland versions gaining popularity due to their ability to function in shallow water. These tools uproot weeds and bury them in the mud through their pull-and-push action, making them both safe and eco-friendly. Weeding should be done at least three times during a growing season, with early weeding being the most effective for completely eliminating young weeds.
FUNCTIONS OF WEEDING EQUIPMENT
Secondary tillage equipment is often used for weed management. Weeders help control weeds between planted crops or before sowing. Some weeding machines use mechanical methods to remove unwanted plants without the need for chemicals.
Usage Instructions
• Early weeding is essential: Perform the weeding within 20 days after sowing.
• Delayed weeding can lead to competition between paddy and weeds, harming the crop.
• Move the weeding machine back and forth between rows.
• Conduct a second round of weeding after 15 days, and if possible, a third.

Origin of weeds : Weeds originated together with crop plants. They have been there since the man started cultivating crops about 10,000 BC. Man during his stage of development, explored certain crop plant to suit his own taste and fancy and cultivated them as ‘crops’. The unexplored / unwanted / troublesome plants which are interfering with his activities are considered as weeds. About 30,000 plants species have been identified as definite weeds in the World. Which are infesting crop lands, water bodies, gardens, orchards, road sides, railway lines, irrigation channels etc.

Plants are differentiated into

a) Crops: Which meet the needs of human being.

b) Weeds: Which compete or interfere in human affairs.

Jethrotull is the first person to use the word weed.

3.1. Cereals and millets

3.1.1. Rice

1. Major weeds

Grasses

Weeds are the plants growing where and when they are not desired. They compete with crops for soil moisture, nutrients, solar radiation and space, and thus reduce crop yields. Weeds also act as alternate hosts that harbour insect pests and diseases and other microorganisms. Some weeds release poisonous substances into the soil which may be harmful to crop plants, human and livestock. Weeds reduce the quality of marketable produce and render harvesting difficult, leading to increased expenditure on labours, equipment and chemicals for their removal.

Classification of weeds

A. Based on life cycle

Annuals-Complete their life cycle in a year or in a single growing season. Based on the season they may be summer annuals and winter annuals.
Summer annual e.g, Echinochloa crusgalli

Weeds are the plants, which grow where they are not wanted. Jethro Tull (1731) coined the word weed. Weeds can also be referred to as plants out of place.

Definition

Weeds are unwanted and undesirable plant that interfere with utilization of land and water resources and thus, adversely affect crop production and human welfare.

In organic agriculture weeds are treated as childrens of the soil.

In the world 30,000 species of weeds have been listed, of which nearly 18,000 cause serious damage to agricultural production. Eighteen weeds are considered as the most serious in the world and about twenty six species have been listed as principal weeds in crop fields of India, and are listed in annexure V

A. Answer the following questions:

1.    What is proximate analysis?

Ans: Proximate analysisis a systemforapproximatingthenutritive valueof a feedstuff without actually usingit in a feedingtrial.

2.    Why proximate analysis is called Weende analysis?

Ans: In 1865, two scientists namely Wilhelm Henneberg and FriedrichStohmanndeviseda methodcalledWeende analysis/ proximate analysis at Weende Experiment Station, near the University of Goettingen, Germany. Hence, it is called ‘Weende Analysis’.

3.    Write the six proximate principles?

Ans: Water (moisture), ether extract (crude fat), crude fibre, total ash, crude protein and nitrogen free extract (NFE).

4.    Why ether extract is also called as crude fat?

Ans: As it is composed of true fats (glycerides of fattyacids) along with other substances like hydrocarbons, free fatty acids, fat solublevitamins,pigmentslike carotene & chlorophyll,waxes, sterols,lecithin(phospholipids), alkali substances,volatile oils and resins.

5.    What is NFE?

Introduction

In a research laboratory, we frequently need weigh chemicals and prepare different solutions of varying strength, as per the requirements. Accuracy in weighing and preparation of solution, with respect to weight/volume and strength, determines the success of experiment. In turn, the accuracy depends on weighing of solid chemical and/or measuring the volume of liquid chemical/making up the volume. In this Chapter, weighing of chemicals using appropriate weighing balance, preparation of solutions of different strength, their dilution, and precautions while preparing will be discuss in brief.

Weighing of Chemical

The primary method to determine the amount of chemicals to be used is weighing the chemical by using a balance.

In general, there are two types of balances to weigh chemicals in a laboratory:

1. Standard laboratory balance

2. Analytical balance

Standard Laboratory Balance

Generally, a standard laboratory balance is used for weighing a chemical when an error of ±0.02 g is acceptable. It is also used for pre-weighing, where approximate mass needs to be determined. Precise mass of the chemical is then determined using an analytical balance. Following are the steps in using a weighing balance in a laboratory.

Introduction

Welding is a fabrication process in which two or more materials or metal pieces are joined or fused with the application of heat, pressure, or both allowing them to cool and this causes fusion. Besides the work piece, a filler material is also sometimes added to the joint to form a pool of molten material that cools to form a joint based on welding and that will be stronger than the parent metal.

Arc Welding and its Types

It is a process of joining two metals using an electric current generated by the power supply, which gives the required amount of heat to metal pieces through which the metals melt and when the metal cools, which results in the binding of the two metals. In the case of this type of welding, the power supply is given, which creates an electric arc between the electrode and the metal rod. Both A.C. or D.C. power supplies can be used in arc welding and both consumable and non-consumable rods can be used.

All farmed animals are transported at some stage in their lives, sometimes to places where food is more readily available, sometimes to a different owner or a different place of keeping and sometimes to slaughter. The handling, loading, transporting and unloading of animals can have very substantial effects on their welfare. Wherever   poor welfare associated with the transport of animals is prevented, there is an immediate financial advantage because mortality rates and carcass downgrading are reduced. The attitude towards animals has major consequences on animal welfare during transportation. Therefore, laws and codes of practice can also have significant effects on animal welfare during transport. In order to produce guidelines that can be used to prevent or minimise poor welfare in animals during transport, it is necessary to be aware of the biological functioning of the animals concerned and the attitudes and actions of the people involved in the handling and transport procedures.

Fish are Sentient Animals

There is strong increasing evidence that finfish, like other vertebrates are sentient animals. This means that fish are self-aware, they can feel pain and distress, they have long term and short-term memory and to some extent, they can experience emotions.

Fish are intelligent, sensitive creatures and like many other animals, they explore, travel, socialise, hunt and play. Some species care for their young and use tools as humans do. Fish are sentient animals capable of suffering and feeling pain. Most fish have highly developed senses with excellent taste, smell, hearing and colour vision. Until fairly recently, many people didn’t realise that fish were sentient or feel pain, and the mental abilities of fish were given limited attention by the scientific community. Now, recent discoveries open up a new world of understanding. Far more complex than we ever realised, f ish live rich social lives: communicating; hunting cooperatively; and, in some cases, developing cultural traits. Consensus arrived in the mid-2000s around science demonstrating high-level pain perception in fish, and examinations of fish behaviour are beginning to reveal a picture of fish as complex, social and emotional beings. Appreciation of these facts are not widespread in civil society, but identified in time for the principle of fish welfare to be recognised by legislation by the European Union.

In India, the cow is a worshipped as symbol of wealth, strength, abundance, altruistic giving and full of earthly life. Cows are traditionally treated as a sacred animal. Dairy products are extensively used in India and are one of the most essential nutritional components of meals.
 
The laws governing cattle slaughter is shown in entry 15 of the State List of the Seventh Schedule of the Constitution, meaning that State legislatures have exclusive powers to legislate the prevention of slaughter and preservation of cattle. Some States allow the slaughter of cattle with restrictions like a “fit-for-slaughter” certificate which may be issued depending on factors like age and gender of cattle, continued economic viability etc. Others completely ban cattle slaughter, while there is no restriction in a few states. Prohibition of cow slaughter is a Directive Principles of State Policy contained in Article 48 of the Constitution.

15.1 Introduction

The laws governing the flow of water in wells are referred to as the hydraulics of wells. Just like surface water flows from a higher elevation to a lower elevation by gravity, groundwater also flows from a region of higher water table to a region of lower water table. This difference of water table measured by any two piezometers divided by the longitudinal distance between them is called as hydraulic gradient. Hydraulic gradient plays a dominant role in deciding the flow of groundwater. This hydraulic gradient together with the hydraulic conductivity of the aquifer material forms the main law of well hydraulics called as Darcy’s law. An understanding of Darcy’s law together with some other laws as discussed subsequently in this chapter is essential in order to know the discharge of a well in a particular formation. Darcy’s law is valid for studying groundwater flow in alluvial formations. However, it is not valid for aquifers having hard rock areas.

11.1 Introduction

The laws governing the flow of water in wells are referred to as the hydraulics of wells. Just like surface water flows from a higher elevation to a lower elevation by gravity, groundwater also flows from a region of higher water table to a region of lower water table. This difference of water table measured by any two piezometers divided by the longitudinal distance between them is called as hydraulic gradient. Hydraulic gradient plays a dominant role in deciding the flow of groundwater. This hydraulic gradient together with the hydraulic conductivity of the aquifer material forms the main law of well hydraulics called as Darcy’s law. An understanding of Darcy’s law together with some other laws as discussed subsequently in this chapter is essential in order to know the discharge of a well in a particular formation. Darcy’s law is valid for studying groundwater flow in alluvial formations. However, it is not valid for aquifers having hard rock areas.

Introduction

Wells are vertical shafts excavated or holes drilled in earth to the level of water table for extraction. Digging of wells is an age old practice. Shallow dug wells supported communities in the past. Well water is drawn to the ground manually or mechanically using variety of containers made of metal, leather, canvass and wood or a combination of them. Draught animals or electrical power are used to draw water for irrigation.

Water table (Fig.6.1) wells extend below the groundwater table and extract free water. Pumping water from these wells lowers the water level. The well first gains water from the water bearing material in its immediate proximity. Subsequently a cone of depression is formed in the immediate vicinity of the well. Water outside the cone of depression but with in the area of influence is diverted to replace the body of groundwater finding its way in to pumping well.

Pulses are recognized as an integral part of Bengali as well as Indian diet and the ideal supplement of cereals by virtue of their high protein and essential amino acid content.  Pulses are inseparable ingredients of vegetarian diet and one of the cheapest sources of dietary nutrition protein in the state. The present emphasis on soil health, environmental quality and economic consideration, has stimulated a paradigm shift in cropping patterns leading to pulse based cropping systems. Any cropping system can become compatible and complete only when a pulse crop is included in it. Pulses won a strategic position in intensive as well as subsistence agriculture, as they are excellent source of dietary protein for millions of people, nutritional feed for livestock and having profound ameliorative effect on soil.

West Indian Cherry is a nutritive fruit mainly grown in semi dry and tropical parts of the country. It is native to West Indies and Central and South America and distributed in Southern Florida, Hawaii and other tropical and sub tropical regions of the world. West Indian Cherry received considerable attention in the 1950’s in its area of distribution because of its extremely high vitamin C content (2000-4600 mg / 100 gm of edible matter). It has been considered to be far superior to guava (Psidium guajava L.) as a potential source of vitamin c and it is richer than even the Indian gooseberry (Phyllanthus emblica L.), which is reported to contain roughly 800 mg of ascorbic acid per 100 g of edible matter. One fruit the size of a large cherry can furnish a man’s daily requirement of this vitamin. Thus the fruit of West Indian Cherry can rightly be called as the “pill of nature’s vitamin”. The fruit can be utilized for the production of crystalline vitamin C. The fruit is also rich in vitamin A, iron and can be consumed fresh or can be used in preparation of sherbet, ice cream, jelly and baby foods, fruit nectars and soft drinks. The juice can also be used to fortify ascorbic acid content of various other products and fruit juices to improve their nutritive value. It can withstand mild frost and drought. Fruits are good source of vitamin C and bark yields tannin (Chadha, 2001).

WNV was first identified in the West Nile district of Uganda in 1937. Reported in Western Hemisphere for the first time in 1999, in New York City. The virus had until that time been found only in Africa, Eastern Europe, West Asia and the Middle East.

Principle

Western blot analysis (also called protein immunoblot) is a useful tool for the detection of proteins in biological samples. It uses gel electrophoresis to separate native or denatured proteins by the length of the polypeptide (denaturing conditions) or by the 3-D structure of the protein (native/ non-denaturing conditions). The proteins are then transferred to a membrane (typically nitrocellulose), where they are probed (detected) using antibodies specific to the target protein.  It is a technique for analyzing and identifying protein antigens: the proteins are separated by electrophoresis in polyacrylamide gel, then transferred (“blotted”) onto a nitrocellulose membrane or treated paper, where they bind in the same pattern as they formed in the gel. The antigen is overlaid first with antibody, then with anti-immunoglobulin or protein A labeled with radioisotope, fluorescent dye, or enzyme. 

The method originated from the laboratory of George Stark at Stanford. The name “Western blot” was given to the technique by W. Neal Burnette and is a play on the name “Southern blot”, a technique for DNA detection developed earlier by Edwin Southern. Detection of RNA is termed northern blotting and the detection of posttranslational modification of protein is termed “Eastern blotting”.

Introduction

Western blot analysis can detect one protein in a mixture of any number of proteins while giving you information about the size of the protein. It does not matter whether the protein has been synthesized in vivo or in vitro. This method is, however, dependent on the use of a high-quality antibody directed against a desired protein. So you must be able to produce at least a small portion of the protein from a cloned DNA fragment. You will use this antibody as a probe to detect the protein of interest.

Western blotting tells you how much protein has accumulated in cells. If you are interested in the rate of synthesis of a protein, Radio-Immune Precipitation (RIP) may be the best assay for you. Also, if a protein is degraded quickly, Western blotting won’t detect it well; you’ll need to use (RIP). See the section on RIP for more information, as well as a helpful comparative chart that illustrates the differences between these two techniques.

Introduction

The western blot (alternatively, protein immunoblot) is an analytical technique used to detect specific proteins in a given sample of tissue homogenate or extract. It uses gel electrophoresis to separate native or denatured proteins by the length of the polypeptide (denaturing conditions) or by the 3-D structure of the protein (native/non-denaturing conditions). The proteins are then transferred to a membrane (typically nitrocellulose or PVDF), where they are probed (detected) using antibodies specific to the target protein.

There are now many reagent companies that specialize in providing antibodies (both monoclonal and polyclonal antibodies) against tens of thousands of different proteins. Commercial antibodies can be expensive, although the unbound antibody can be reused between experiments. This method is used in the fields of molecular biology, biochemistry, immunogenetics and other molecular biology disciplines.

Other related techniques include using antibodies to detect proteins in tissues and cells by immunostaining and enzyme-linked immunosorbent assay (ELISA).

The method originated from the laboratory of George Stark at Stanford. The name western blot was given to the technique by W. Neal Burnette and is a play on the name Southern blot, a technique for DNA detection developed earlier by Edwin Southern. Detection of RNA is termed northern blotting and the detection of post-translational modification of protein is termed Eastern blotting.

Introduction

Wet ashing is suitable for the determination of Ca, Cu, Fe, Mg, Mn, K, Na, Se and Zn in biological samples and may be applicable to the determination of other elements as well.

The organic matter of the sample is oxidized with concentrated nitric acid and perchloric acids. The acids are partially removed by volatilization and the solube mineral constituents remain dissolved in nitric acid. Any silica present is dehydrated and made insoluble.

Introduction

Wet ashing is suitable for the determination of Ca, Cu, Fe, Mg, Mn, K, Na, Se and Zn in biological samples and may be applicable to the determination of other elements as well.

The organic matter of the sample is oxidized with concentrated nitric acid and perchloric acids. The acids are partially removed by volatilization and the solube mineral constituents remain dissolved in nitric acid. Any silica present is dehydrated and made insoluble.

Thisprocedure estimates aggregatestabilitytoimpact ofraindropsand water erosion. Wet sieving procedure was originally proposed by Yoder, 1936. Later, the procedure was modified byKemper and Rosenau, 1986.

Equipment

1. Yoder type sieve shaking electrically operated machine (3/4 inch stroke at 30 strokes per minute)
2. Concentric sieves of various sizes of pores to fit properly into the machine.
3. Weighing balance

When certain disease-causing bacteria or pathogens contaminate food, they can cause foodborne illness, often called “food poisoning”. Foods that are contaminated may not look, taste or smell any different from foods that are safe to eat. Salmonella, Campylobacter, Listeria and Escherichia coli are common bacteria causing foodborne illness. Some foodborne illnesses are mild where most people get better within a few days, but illness can sometimes be more severe and fatal. Bacillus cereus can form heat resistant spores. On cooking the food with these spores the heat resistant toxin is left at room temperature. Reheating or lightly cooking the food does not destroy these toxins. Most types of foodborne illnesses cause symptoms like nausea, vomiting, watery diarrhea, abdominal pain and cramps. Fever and/or the presence of blood or mucus in the stool are signs of bacterial infection that may require a medical consultation. Proper food handling is vital to prevent most foodborne illnesses and diseases. WHO has given keys towards safer food which should be followed. Unsafe food containing harmful bacteria, viruses, parasites or chemical substances, causes more than 200 diseases which range from diarrhoea to cancers. Foodborne and waterborne diarrhoeal diseases kill around 2 million people worldwide annually, including many children. A single foodborne bacterium can grow into more than two million bacteria in just seven hours under the right conditions. Foodborne pathogen called Listeria sp. can survive and sometimes grow on foods being stored in the refrigerator. Hepatitis A virus can cause long-lasting liver disease and spreads typically through raw or undercooked seafood or contaminated raw produce. It is estimated that more than 250 million people worldwide suffer food allergies. The boiling temperature (smoke point) of cooking oil is above 200 °C. The boiling point of water is 100 °C.

According to the World Health Day (WHO,2015) food contamination happens when food are corrupted with another substance. It can happen during the process of production, transportation, packaging, storage, sales and cooking process. The contamination can be physical, chemical and biological. Faulde et al., (2013) studied the infection caused to patients by mothfly

Productivity growth in agriculture is anticipated to drive successful structural transformation and industrialization in pre-industrial developing countries that possess untapped agricultural potential. Historical precedent shows that agricultural revolutions often precede industrial revolutions in countries with predominantly rural populations. Recent industrialization experiences in countries like China, India, and Brazil reinforce this perspective. Achieving productivity growth in agriculture necessitates the availability and adoption of technological innovations within the farming community. In recent years, attention has increasingly focused on understanding the delay between the emergence of promising innovations and their adoption.

Numerous factors contribute to the lack of technology adoption, including credit constraints, limited insurance coverage, high transaction costs, and behavioral biases. Moreover, the availability of information about new technologies is a critical, albeit not sufficient, condition for adoption. Consequently, addressing potential information failures that hinder farmers' adoption of available technologies is essential. This underscores the importance of extension services, as well as the transfer of information through social networks, agro dealers, and commercial partners in the agricultural value chain.

After the agricultural activities a number of by-products are obtained and these are known as agricultural waste. These include residues of different crops like stalks, straws, leaves, roots, husks and shells. The animal waste is in the form of manure. All these agricultural wastes are free of cost however; they can be utilized as an important resource (Lionel and Arnold, 1931). Agrawal (1998) has mentioned India as the final dumpyard. The wastes obtained from various resources can be converted into heat, steam, charcoal, methanol, ethanol, biofuel, compost, energy, biogas, construction and high valued chemical compounds. Many times these agri-industrial wastes are not completely utilized and either they rot in open areas or are burned in the fields.

Abstract

Bioinformatics is an important interdisciplinary field that brings together several areas of science, including molecular biology, biostatistics, and computer science (vis-a-vis information technology). With the rapid increase in the sequencing of DNA/RNA/protein molecules, as well as the growing understanding of the interconnections between different areas of biological science, the importance of bioinformatics is only increasing. This chapter seems to provide a thorough introduction to the definition, concept, and importance of bioinformatics. It also appears to highlight the relevance and potential scope of the subject for students interested in pursuing a career in the field. As bioinformatics continues to evolve and expand, it is likely to become an increasingly important area of research and development in the life sciences.