eChapters

Developmental Anomalies

Persistent right aortic arch

This is a developmental anomaly of aorta in which the aorta develops from right arch present on right side of trachea and oesophagus. The ductus arteriosus forms a ring around trachea and oesophagus by connecting aorta and pulmonary artery. This ring causes partial obstruction of trachea and/or oesophagus.

Patent ductus arteriosus

The ductus arteriosus is a short blood vessel which connects pulmonary artery to aorta in foetal life for diversion of blood. Normally, soon after birth this duct is sealed and remains in the form of a ligamentum arteriosum. But sometimes this ductus arteriosus remains open and blood is continuously shunted between aorta and pulmonary artery, after leading to congestive heart failure, pulmonary hypertension and cyanosis due to mixing of venous and arterial blood (Fig. 3.1).

Chlamydiosis

Chlamydiosis is an infectious disease of animals caused by Chlamydia sp. and characterized by encephalitis, polyarthritis and pneumonia in calves and abortions in cows and sheep.

Etiology

• Chlamydia psittacii

Pathogenesis

Chlamydial infection spreads through inhalation of contaminated dust from infected birds. Organism multiplies in lungs and through blood it spreads to liver, spleen, kidneys, brain, joints and placenta to cause pathology.

Characteristic symptoms

Calves

• Fever, dyspnoea

• Nasal discharge, hypersalivation

• Swelling of joints

Developmental Anomalies

Congenital icthyosis

Congenital icthyosis is scaly epidermis which resembles the skin of fish and occurs due to a simple autosomal recessive homozygous gene in calves. This condition is characterized by scaly, horny, thick epidermis divided into plates by deep fissures. Microscopically, there is thick keratin layer over the epidermis (Fig.1.1).

Epitheliogenesis imperfecta

Epitheliogenesis imperfecta is a congenital defect characterized by discontinuity of epithelium on skin leaving patches without squamous epithelium mostly at feet, claws and oral mucosa. Such defect may occur in calves which succumb to infection after birth or such foetus may abort. This disease condition is inherited as an autosomal recessive trait.

Developmental Anomalies

Epitheliogenesis imperfecta of tongue

Abnormal smooth surface of tongue due to small filiform papillae. It occurs as a defect in autosomal recessive gene and occurs in Holstein-Friesian cattle. This is also known as smooth tongue.

Cleft palate

This is most common congenital abnormality that occurs due to failure of oral nasal cavity to divide leaving cleft. It may also extend towards lips producing ‘harelip’ condition.

Mega colon

There is distention of colon which abruptly terminates in rectum due to mutant gene in dogs.

Pathology of Endocrine System

Pathology of Hypothalamus

The lesions in hypothalamus may cause diabetes insipidus characterized by polydipsia and polyuria with low specific gravity of urine. It occurs due to deficiency of antidiuretic hormone vasopressin.

Etiology/ Occurrence

• Lesions in hypothalamus and/or pituitary.

• Adenoma and adenocarcinoma of pituitary.

• Necrosis of hypothalamic nuclei due to larval migration.

Ringworm

Ringworm is a fungal disease of skin affecting animals characterized by popular skin lesions in circular form discharging serus exudate.

Etiology

• Microsporum canis- dogs

• M. gypseum- dogs, horse, pig

• Trichophyton verrucosum- bovines

• T. equinum- horses

Pathogenesis

The fungi enter in skin through abrasion and the hyphae appear in stratum corneum after germination and invade the hair follicles. The hyphae growth and spore formation in stratum corneum leads to hyperkeratosis and the fungus spreads centrifugally from the point of primary invasion leading to ring shaped lesion (Fig.8.1).

Aspergillosis

Aspergillosis is a fungal disease of poultry caused by different species of Aspergillus sp and characterized by granulomatous nodules in lungs, thickening of air sacs and presence of fungal growth in lungs and air sacs in early age of chicks. It is also known as Brooders pneumonia (Fig.8.1).

Etiology

• Aspergillus fumigatus

• A. flavus

• A. nidulans

• A. glaucus

• A. niger

• A. candidus

Female Genital System

Developmental Anomalies

Agenesis

Absence of ovary, uterus, oviduct and cervix in females. It may be unilateral or bilateral.

Hypoplasia

Complete or partial lack of germ cells in ovaries. Hypoplasia of uterus is related with agenesis of gonads. Ovaries of freemartin are also hypoplastic. Hermaphrodite animal has ovary and testicular tissue both in the gonads.

Hermaphroditism

In hermaphrodites, there is presence of organs of both sexes in same individual animal. Both ovarian and testicular tissue occur in one animal leads to sterility in animal (true hermaphrodite) while in pseudohermaphrodite the gonadal tissue of only one sex is present but there is some degree of development of opposite sex organs.

Developmental Anomalies

Hereditary anemia

Hereditary anemia has been reported in mice due to defects in erythropoiesis or reduced vitality of erythrocytes. Erythropenia along with leucopenia occurs in mouse foetus on 20th day of gestation due to defective autosomal chromosome 4. Sex linked anemia in mouse is hypochromic with deficient bone marrow and occurs in hemizygus males or homozygus females. This anemia occurs due to deficiency of iron as a result of poor absorption from gastrointestinal tract.

Autoimmune hemolytic anemia in foals

It occurs due to incompatible blood group antigens of male and female parents. The mare does not have that blood group antigen but foetus acquires it from father. The foetal blood exposed to dam through placental exchanges leads to induction of antibody production in mares against foetal blood group antigen. These antibodies accumulate in colustrum and when foal suck the milk from mares, they are readily absorbed through G.I. tract of foals in blood and cause destruction of erythrocytes leading to anemia.

Tyzzer’s disease

Tyzzer’s disease is an acute infectious disease of laboratory animals including rats caused by Clostridium spp and Characterized by watery diarrhoea, necrotic hepatitis and death

Etiology

• Clostridium piliforme

• Gram positive, Spore forming, Anaerobe

Pathogenesis

• Horizontal transmission- faecal oral route

• Contaminated feed, water

• Bacteria in gut causing enteritis

Pathology of Muscles

Equine Rhabdomyolysis

It is also known as Azoturia or Monday Morning Disease. The disease occurs in well fed horse after a spell of inactivity. Suddenly after walking a few steps, the horse is unable to move further and feels pain with intense sweating and hardening of muscles.

Etiology

• Accumulation of lactic acid in muscles.

• High glycogen storage.

• Lack of oxygen supply.

Macroscopic features

• Hardening of muscle just like wood.

• Urine is dark brown with myoglobin – myoglobinuria.

• Tonic spasms in muscles.

• Atrophy of affected muscles in chronic cases.

Contagious

Bovine Pleuropneumonia (CBPP) Contagious bovine pleuropneumonia (CBPP) is an infectious disease of cattle caused by Mycoplasma sp. and characterized by cuprous pneumonia, pleurisy and dilation of lymph vessels (Fig.5.1).

Etiology

• Mycoplasma mycoides

Pathogenesis

The infection spreads through inhalation of droplets from infected animals. The recovered animals act as source of infection at least for a period of 3 years. After entering through respiratory tract the organism reaches to bronchioles. It may remain in retropharyngeal gland from where it may spread in whole body. The organism from bronchioles enter into interlobular septa and causes inflammation followed by edema which causes dilation and subsequent thrombosis of lymph and blood vessels prior to development of pneumonic lesions. Death occurs due to anoxia and toxaemia.

Chronic Respiratory Disease (CRD)

Chronic respiratory disease is caused by Mycoplasma gallisepticum and E.coli in birds under poor management and characterized by cloudy air sacs with thickening of their wall, accumulation of cheesy material in air sacs and lungs (Fig.6.1).

Etiology

• Mycoplasma gallisepticum

• E.coli

• Bad management like poor ventilation and inclement weather conditions

• Disease occurs more during winter and rainy season.

Nervous system is composed of brain, spinal cord, and peripheral nerves. The neuron is a basic functional unit of nervous system. Necrosis of neurons in brain is known as encephalomalacia while necrosis of neurons in spinal cord is termed as myelomalacia. If the necrosis occurs in grey matter it is known as polioencephalomalacia while necrosis of neurons in white matter is called as leukoencephalomalacia. There are three types of scavenger cells in nervous system known as microglial, oligodendroglial and astrocytes. Microglial cells surround the necrotic neurons and are known as satellite cells and the process is called as satellitosis. As the neuron dies, it is engulfed by microglial cell and this process is termed as neuronophagia. The necrosis of nerve fibers starts from myelin sheath and this change is called demyelination or Wallerian degeneration.

Nervous system is composed of brain, spinal cord, and peripheral nerves. The neuron is a basic functional unit of nervous system. Necrosis of neurons in brain is known as encephalomalacia while necrosis of neurons in spinal cord is termed as myelomalacia. If the necrosis occurs in grey matter it is known as polioencephalomalacia while necrosis of neurons in white matter is called as leukoencephalomalacia. There are three types of scavenger cells in nervous system known as microglial, oligodendroglial and astrocytes. Microglial cells surround the necrotic neurons and are known as satellite cells and the process is called as satellitosis. As the neuron dies, it is engulfed by microglial cell and this process is termed as neuronophagia. The necrosis of nerve fibers starts from myelin sheath and this change is called demyelination or Wallerian degeneration.

Equine Rhabdomyolysis

It is also known as Azoturia or Monday Morning Disease. The disease occurs in well fed horse after a spell of inactivity. Suddenly after walking a few steps, the horse is unable to move further and feels pain with intense sweating and hardening of muscles.

Etiology

• Accumulation of lactic acid in muscles.

• High glycogen storage.

• Lack of oxygen supply.

Pathology of nutritional deficiency diseases are described in chapter etiology of this book. However, specific deficiency of nutrition that leads to development of clinical signs and lesions in poultry are summarized as under (Fig.2.1 & Fig.2.2):

Vitamin Deficiency

1. Hypovitaminosis A

• Vitamin A is considered infection resisting vitamin because it facilitates the proper development of bursa, immunity and epithelium on mucosal and skin surfaces.

• Deficiency of vitamin A leads to swollen glands in oesophagus i.e. nutritional roup.

Trypanosomosis

Trypanosomosis is an infectious disease of animals caused by protozoan parasite and characterized by emaciation, enlargement of spleen and lymph nodes, petechiae on serous membranes, ulceration on tongue and gastric mucosa and gelatinous exudate in subcutaneous region.

Etiology

• Trypanosoma evansi

Pathogenesis

The disease is mainly transmitted through bite of flies like Tabanus, Stomoxys, Haematopota etc. The carrier animals remain as potential source of infection. The pathogenesis of disease is not completely known. After entering in mammalian host, trypanosomes multiply in blood stream by binary fission leading to parasitaenia. The parasites has variable surface glycoproteins which cause continuous exposure of immune system leading to hyperplasia of spleen and lymph nodes. In chronic cases, due to formation of antigen- antibody complexes glomerulonephritis and vasculitis is seen.

Roundworms (Nematodes)

1. Ascaridia galli

A. galli is the common roundworm of poultry seen in intestines at the time of necropsy. This parasite may cause retardation of growth, loss of egg production, catarrhal enteritis and sometimes mortality due to obstruction of gut (Fig.9.1).

Etiology

• A. galli parasites are grey, thread like 5-10 cm in length.

• Eggs are elliptical with thick and shiny wall.

Pathogenesis

Transmission occurs through faecal - oral route. The eggs may survive for several months in litter and they take at least 10-15 days to develop the infective stage. The eggs of parasites hatch in proventriculus or intestine to develop fully grown parasite within 40-50 days.

Spongiform encephalopathy

Spongiform encephalopathy is an infectious disease of animals caused by prion proteins and characterized by presence of vacuoles in brain.

Etiology

• Prion proteins

• Sheep – Scrapie or Ovine spongiform encephalopathy

• Cattle - Bovine spongiform encephalopathy (Mad cow disease)

• Feline encephalopathy

Pathogenesis

Scrapie is also known as ovine spongiform encephalopathy. The principle means of transmission of disease is from infected mother to their lambs early in life; placental transmission has also been reported. The incubation period of disease is very long (2-5 year). The clinical form is restricted in adults. The prion proteins (PrP) occur normally in the central nervous system of all domestic animals and man bounded with neuronal surface. Animal susceptible to prion disease have a gene (PrP gene) which encodes for normal “Prion protein (PrP)” or “cellular prion protein (PrPc). In scrapie prion protein (PrPsc)/ scrapie associated fibril protein (SAI) is generated which are resistant for protease digestion. Accumulation of PrPsc in neural tissues appears to be the cause of the pathology in prion disease. When prion protein contaminated meat and bone meal are fed to the cattle as part of their concentration, the agent (prion) got introduced into cattle. Prion protein (PrP) on reaching brain slowly and progressively converted into and abnormal form (PrP sc) and this abnormal protein causes development of lesions including vacuolation in nerve cells.

Anaplasmosis

Anaplasmosis is an infectious disease of animals caused by a rickettsia and characterized by icterus, enlargement of spleen, pale tissues, thin watery blood and petechiae over serous membranes (Fig.4.1).

Etiology

• Anaplasma centrate

• A. marginale

• A. ovis

Pathogenesis

The disease is transmitted through bite of tick (Boophilus), biting flies (Tabanus) and also in some cases due to mosquitoes. It is intra cellular organism and multiplies inside the erythrocytes by binary fission. The infected erythrocytes are engulfed by the cells of reticuloendothelial system (spleen, bone marrow). The process of erythrophagocytosis cause extra vascular haemolysis leading to anemia. It also causes autoimmune reaction leading to lysis of erythrocytes.

Spirochetosis

Spirochetosis is caused by a spiral shaped organism Borrelia anserina and characterized by greenish diarrhoea, enlarged and mottled spleen, small necrotic patches on liver and linear haemorrhage in proventriculus. This disease is transmitted by a tick Argas persicus and thus also known as “tick fever” or “tick paralysis”.

Etiology

• Spirochete Borrelia anserina

• Spiral shape 8-24m long and 0.2 to 0.3 m wide microorganism having 8-11 spirals.

• Stained with aniline dyes

Leptospirosis

Leptospirosis is an infectious disease of animals caused by spirocheate Leptospria sp. and characterized by widespread haemorrhage in visceral organs, nephritis, icterus, hepatitis and anemia (Fig.6.1).

Etiology

• Leptospira ictehaemorrhagae

• L. pomona

Pathogenesis

The organism is transmitted through direct contact with urine of infected animals or ingestion of urine contaminated feed or water. It can also be transmitted through aborted fetuses and infected uterine discharges. The organism enters through abraded skin and mucous membrane and reaches in blood and multiplies rapidly in blood producing septicemia and high rise in body temperature. Thereafter the organism localizes in the kidneys leading to acute or chronic nephritis. In kidneys, it multiplies in proximal convoluted tubules (PCT) and is excreted in urine which acts as source of infection.

Developmental Anomalies

Aplasia

Absence of one or both kidneys. Absence of one kidney is observed in animals with compensatory hypertrophy of another kidney and such animals may survive well.

Hypoplasia

The size of kidneys remains small as they don’t grow properly due to defect in a single recessive autosomal gene.

Cyst in kidney

Single or multiple cysts in pig and dog kidney are reported with tinged yellow colour. They may arise from nephron due to its distension. Presence of multiple cysts is also termed as congenital polycystic kidney.

Type-I cysts are formed due to dilation and hyperplasia of collecting tubules resulting in spongiform kidneys. In such neonates cystic bile ducts are also present.

Cannibalism

Cannibalism is a bad habit of birds in which the birds attack their fellow birds and eat their flesh. It is done through sharp end of beak, which causes deep wounds specially on vent. Sometimes the wounds are so deep that leads to death of affected bird. Two types of cannibalism vices are common i.e. vent pecking and feather pecking.

Cause / Predisposing Factors

• Over crowding

• Genetic predisposition

• Hemorrhage in external genitalia

• Protein deficiency (arginine and methionine deficiency)

• Loss of feathers • Wounds

• Prolapse of cloaca

Foot and Mouth disease

Foot and mouth disease is a contagious viral disease of cloven footed animals caused by a picorna virus and characterized by presence of vesicles in oral mucosa and foot (Fig.1.1).

Etiology

• RNA virus of picornaviridae family

• Picorna virus

• Serotypes A,O,C, SAT-1, SAT-2, SAT-3, Asia-1, serotype ‘O’ is most common in India.

Pathogenesis

Inhalation is the main route of infection in ruminants; however, ingestion of contaminated feed and water, inoculation of contaminated vaccines, insemination with contaminated semen and contact with fomites such as clothing, instruments etc. may also transmit the infection. When animal gets infected through respiratory tract, viral replication starts in pharynx followed by viraemic spread to other tissues and organs like epithelium of mouth. Viral excretion commences about 24 hours prior to the onset of clinical form of disease and continues for several days. The aerosols of infected animals contain large amount of virus particularly of swine. Large amount of virus is excreted in milk. In cattle and sheep, virus may be detectable up to 2 years and 6 months of exposure, respectively.

Feline Leukemia

Feline leukemia is an infectious viral disease of cats, lion, tiger etc. caused by oncorna virus and characterized by malignant lymphoma, lymphocytosis and immunosuppression. It is also known as feline lymphoma or feline lymphosarcoma.

Etiology

• Oncorna virus of retroviridae family

• Type C oncorna virus, RNA virus has reverse transcriptase

Pathogenesis

The virus is transmitted horizontally through salivary and nasal secretions of sick cats. It affects lymphocytes causing their proliferation leading to production of neoplastic growth.

Characteristic symptoms

• Enlargement of superficial lymph nodes

• Lymphocytosis

• Chronic diarrhoea

• Abortion

Pathology of Upper Respiratory Tract

In many infectious diseases, there is inflammation of mucosa of upper respiratory passage leading to nasal discharge which is catarrhal, purulent or fibrinous, depending on the type of infection. The infection may extend to lower parts of respiratory tract and reach the lungs causing pathological alterations. Rhinitis is the inflammation of nasal mucosa (Fig. 4.1). Sinusitis is the inflammation of sinuses e.g. frontal sinusitis in dehorned cattle. The larvae of botfly Oestrus ovis enter the nasal passage and migrate up to frontal sinuses and turbinate bones and cause mucopurulent inflammation. Similarly, leeches (Dinobdella ferox) is known to cause nasal cavity inflammation in domestic animals and suck blood. Rhinitis is caused by Bordetella bronchiseptica in pigs and is characterized by mucopurulent exudate, disappearance of nasal septum, retarded growth of snout and plugging of passage by solidified exudate and dead tissue. This condition is known as porcine atrophic rhinitis. Epistaxis is bleeding from nasal passage due to trauma, neoplasm (Fig.4.2A) and ulcerative lesions as a result of infections (Fig.4.2B). Pharyngitis is the inflammation of pharynx while laryngitis is the inflammation of larynx.

Pranab Mukherjee in his budget speech delivered on 26 February 2010 announced: ‘We are now ready with the draft Food Security Bill which will be placed in the public domain very soon.’  Although no official draft has been placed on the website of the concerned Ministry, several leading organisations and individuals have questioned the adequacy of the steps proposed to be taken under the Bill for achieving the goal of a hunger-free India.  Based on Article 21 of the Constitution, the Supreme Court of India has rightly regarded the right to food as a fundamental requirement for the right to life.  Many steps have been taken since Independence to adopt Mahatma Gandhi’s advice for an antyodaya approach to hunger elimination. In spite of numerous measures and social safety net programmes, the number of undernourished persons has increased from about 210 million in 1990-92 to 252 million in 2004-06.  About half of the world’s under-nourished children are in India.  Also, there has been a general decline in per capita calorie consumption in recent decades.  Grain mountains and hungry millions continue to co-exist.

Growth of a microorganism implies an increase in amount of protoplasm, formation of new structures and eventually formation of new cells. Balanced growth means cell components increase in proportion to each other and unbalanced growth means cell components increase in a non constant relationship to each other

Microbial growth and growth curve

Phases of growth

When bacteria are grown in the laboratory in liquid medium, the medium becomes cloudy or turbid. It is possible to measure the increase in numbers of bacteria at various time intervals and plot the values on a graph representing a growth curve.

Lag Phase: When cells are first inoculated into fresh medium containing all the nutrients they require, they take a short time to adapt before they start to divide. This is termed the lag phase.

ABSTRACT

Information Technology includes computers and communication technology along with associated software. I.T. can be defined as the technology of creation, processing, storage, retrieval and transmission of data and information. Transmission of data and information between through local national, regional and global telecommunication channels are not new to us. Computer networks have been the real facilitators of data and information interchange in the individual and corporate levels. LANS and WANS are the good examples of it. Developing countries have a critical stake in how successfully they cope with the trade, environmental, energy, healthy, agricultural, industrial, population and other challenges facing them as they enter the information age. The World is experiencing an explosive growth of IT at the moment. There have been tremendous impacts of I.T. on the trade, commerce and industries of the globe.

Genus : Asimina 
Species : triloba (L.) Dunal
Family : Annonaceae
Chromosome No. : 2n = 18

Uses

The delicious pawpaw fruits are used as dessert. The red or brown streak wood is light in weight hence not used for furniture or allied work. On account of its handsome foliage, large leaves and attractive form, it provides additional attraction when planted in gardens.

The present study was designed to assess the cardio-protective role of oleic acid in myocardial injury. Myocardial injury was induced in rats by intra-peritoneal injection of isoprenaline (ISO; @ 110 mg/kg b.wt) for two consecutive days at 24 h interval. Oleic acid was administered orally (@ 5 mg/kg b.wt or 10 mg/kg b.wt) for 21 days before inducing myocardial injury to evaluate its ameliorative potential. Samples (blood, heart) were collected from different groups of experimental animals 24h after last injection of isoprenaline. Besides evaluation of heart weight to body weight (HW/BW) ratio, myocardial infarct size, oxidative stress parameters and haemato-biochemical parameters, cardio specific biomarkers of injury, ECG, isolated right atrial response and mRNA expression of gene coding for cardiac uncoupling protein-2 (UCP-2) were also quantified. Isoprenaline administration significantly increased the HW/ BW ratio, myocardial infarct size, lipid profiles (total cholesterol, HDL-C, triglyceride) in ISO-induced myocardial injured rats.

The polymerase chain reaction (PCR) is a very powerful new method used for in vitro to amplify a deoxynibonuclic specific region that lies between two regions of known DNA sequence single molecule to million folds in short time. This is achieved by an enzyme taq. DNA polymerase which is thermostable using this enzyme can synthesize microgram quantities of DNA of specified length and sequence from pictogram quantities of complex template in a few hours time.

Many Bacillus species are capable of producing a wide variety of secondary metabolites that are diverse in structure and function. The production of metabolites with antimicrobial activity is one determinant of their ability to control plant diseases. The activity is determined using PCR. PCR consists of an exponential amplification of a DNA fragment, and its principle is based on the mechanism of DNA replication in vivo. dsDNA is denatured to ssDNA, duplicated, and this process is repeated along the reaction according to the following formula

Introduction
In recent years crop yields have increased significantly due the development of new varieties and cultivars. Certain characteristics, like disease resistance, plant height, yield potential, and maturity period, set one variety of a cultivated crop species apart from other variations of the same species. A key element of contemporary agriculture is the precise identification of crop types, which is essential for plant breeding, seed certification, and the defence of intellectual property rights. The increasing demand for improved crop varieties with increased yield, disease resistance, and environmental adaptability has demanded the development of accurate methods for differentiating cultivars (Hannah, 2024). Traditional techniques of variety identification rely on morphological, biochemical, and agronomic features, which can be altered by environmental conditions and are generally time-consuming and labour-intensive. Various molecular marker systems have been developed to differentiate plant varieties and species of agricultural and horticultural significance. For effective seed quality control programs and the preservation of breeders’ rights, it is essential to define the identity, genetic purity, and stability of plant varieties. According to Yuan et al., (2022), precise variety identification is essential for determining genetic purity, analyzing genetic diversity, improving germplasm for better agronomic qualities, and getting rid of duplicate accessions.
For plant protection and production systems of Intellectual Property Rights (IPR) and Plant Biodiversity Register (PBR), accurate cultivar identification is crucial. According to Ghosh et al. (2001), molecular marker approaches are pertinent to PBR registration in the following ways. (1) In order to establish a set of comparison cultivars, genetic distance analysis between the candidate cultivar and the current pool of cultivars is performed. (2) The contribution of the comparison cultivar to PBR registration is then determined, and (3) the use of DNA markers to identify cultivars in cases where PBR infringement is alleged is investigated. The capacity of PCR-based markers to amplify particular DNA sequences has made them popular among molecular marker techniques, enabling accurate identification of genetic variations. Although conventional approaches are still employed for Plant Variety Protection (PVP), molecular techniques can be useful adjuncts that increase the effectiveness of accomplishing this goal. During variety certification, additional information from isozyme analysis, RFLP, SSR, SNP, or other genetic fingerprinting methods can be added to cultivar descriptions. Plant varieties can be legally protected on the basis of precise and unique molecular marker data. Crops with little morphological variation benefit greatly from molecular methods. To guarantee complete protection of cultivars, it is ideal to use both botanical and molecular evaluations (Yu and Chung, 2021). Amplified Fragment Length Polymorphism (AFLP), Random Amplified Polymorphic DNA (RAPD), Simple Sequence Repeat (SSR), and Inter Simple Sequence Repeat (ISSR) are the four main PCR-based markers used in crop variety identification that are the subject of this chapter. In plant genetics, each of these marker systems has special qualities, benefits, and uses. While AFLP markers give high resolution and genome-wide coverage, RAPD markers offer a rapid and economical method of polymorphism detection. Due to their high polymorphism and co-dominant inheritance, SSR markers—also referred to as microsatellites—are perfect for genetic mapping

Sanger Method for DNA Sequencing

One necessity first know a little about the structure of DNA:

1. A segment of DNA, which is ordinarily double stranded, has a specific orientation, as it has a 5' (read as “5 prime”) and a 3' (“3 prime”) end. This can be simply thought of as a front and tail end to the DNA segment.
2. When DNA is synthesized in the lab, the two strands are separated and new bases are added to the 3' end-thus DNA is assembled from the 5' to 3' end.
3. DNA cannot be synthesized from scratch. A short piece of DNA, called a primer, is required for the reaction to begin.
4. Primers are designed such that they are able to bind to the target DNA, the binding of which is the initiator for DNA synthesis.

Abstract

Consumer now-a-days relies on manufacturing and processing standards, particularly to know what ingredients are present, due to dietary, nutritional requirements, or medical conditions (e.g., diabetes orallergies). Modified PCR and combination of PCR with other analytical tools have been successfully used for analysis of various parameters related to functional foods such as detection and quantification of beneficial as well as food borne pathogenic microorganisms, food allergens, raw material source, bioactive compounds, genetically modified foods. Multiplex PCR method has been found to be an efficient tool for simple, rapid, and reliable identification of Lactobacillus and Bifidobacterium in probiotic products. Food allergens like gluten, peanut, hazelnut etc. could be easily detected in foods using PCR, even if present in small quantities. BOX-PCR and PCR-DGGE analysis have been used for identification of bacterial diversity of a naturally fermented functional food (Enzyme). HPLC combined with real time -PCR were successfully used to quantify and analyse compounds of secondary metabolites like phenylpropanoid amides, which represent an important class of nutraceutical having strong antioxidant and chemotherapeutic effects in various transgenic tomato tissues. Detection of active compounds in natural plant products were successfully achieved using PCR techniques. In general PCR have gained more importance as it has high sensitivity, improved precision, wide dynamic range for quantification, genotype based and is quick method of detection and quality control of foods than traditional culture based methods.

Introduction Garden Pea (Pisum sativum L.) is a small, round, green seed that is commonly eaten as a vegetable. It is a legume, which means it is part of the same family as beans, lentils, and peanuts. Its chromosome number is 2n=14. Peas are typically eaten fresh, frozen, or canned, and are often used in soups, stews, and casseroles. They are a good source of protein, fiber, various vitamins and minerals. Peas can be grown in a garden or farm and it is considered a staple food in many countries. Origin and Distribution Garden peas have a long history of cultivation and have been enjoyed as a food source for centuries. The exact origin of garden peas is believed to be in Central Asia. The distribution of garden peas expanded as they were introduced to different regions and adapted to various climates. They were brought to Europe during ancient times and became popular as a staple crop in many countries. The cultivation of garden peas also spread to Asia, Africa, and the Americas through the process of exploration and colonization. In modern times, garden peas are grown globally in both temperate and cool climates.

Downy Mildew
Diagnostic Symptoms
• At first grayish white, moldy growth appears on the lower leaf surface, and a yellowish area appears on the opposite side of the leaf.
• Infected leaves can turn yellow and die if weather is cool and damp.
• Stems may be distorted and stunted.
• Brown blotches appear on pods, and mold may grow inside pods(Fig-2).
Etiology
Scientific Classification
Phylum :Heterokontophyta
Class : Oomycota
Order : Peronosporales
Family :Peronosporaceae
Genus :Peronospora

 

The disease is seen at 3-4 leaves stage. Scattered, irregular, yellowish patches appear on the upper surface of the leaves and stipules. On the corresponding under surface of these patches, a greyish violet fi ne cottony mildew growth is seen. Infected tissue soon dies and turns brown. The disease fi rst appears on lower leaves and later spreads to upper leaves.

The peach tree (Prunus persica L.) is a species of Prunus native to China that bears an edible juicy fruit called a peach. It is a deciduous tree growing to 4–10 m (13–33 ft) tall, belonging to the subfamily Prunoideae of the family Rosaceae. It is classified with the almond in the subgenus Amygdalus within the genus Prunus, distinguished from the other sub genera by the corrugated seed shell. Among the temperate fruit’s peaches require relatively less chilling temperature. Now peach is a commercial crop in Argentina, Austria, Canada, Chile, Europe, USA, China, India and Japan. In India, it grown in hills of Uttar Pradesh, Jammu & Kashmir, Himachal Pradesh, Uttar Pradesh and Punjab.

Cultivars/Varieties: Sun Red, Red, Nectarine, Kateroo, Flordasun, Florda gold, Sharbati, Maygold, Kanto-5, Stark Early Flame, Summerset, Early White Giant, Redglobe, Alexander, First Gold, Early Gold and Sweet Gold.

Uses

Peachs are grown both for dessert and processing purposes. It is also used for making wine. Peach fruit juice is a common drink. Peach kernel has high protein and its oil is used in food, cosmetics and pharmaceutical products. The cake after extraction of oil can be used for various purposes. Peach flowers and leaves are anthelmintic and purgative.

1. Introduction

The peach [Prunus persica (L.) Batsch] is an important fruit crop of temperate regions, all over the world. Important centers of commercial production usually lie between latitudes 30° and 45° North and South. At higher latitudes, minimum winter temperatures and spring frosts are the limiting factors. The peach flower bud is hardy and can tolerate minimum temperature of about -23 to -26° C. Its northern range is extended where minimum temperature are ameliorated by large bodies of water, as western continental seaboards, the great Lakes in the U.S.A. and Canada and the Caspian and Black seas of Eurasia. Mid continental areas are characterized by lower winter temperatures and usually more severe spring frost hazards. Most peach cultivars require 500 to 1000 chill hours below 7.2° C to foliate and bloom. At lower altitudes, the winter requirement is not met. The peach with its smooth skin mutant is known as nectarine. Nectarines can be used in the same way as peaches, and may be considered as substitutes for peaches.

Green peach aphid/peach leaf curl aphid : Brachycaudus helichrysi Aphididae

These are green aphids that suck the sap from growing buds. Leaf buds become weak and result in poor setting and premature fruit fall.
 
Blossom thrips : Thrips rhopalantennalis, T. flavus, T. florum, Haplothrips tenuipennis, Frankliniella dampfi : Thripidae

These are tiny, yellow, pale-brown and black slender insects seen within the flowers and flower buds. Adults and nymphs lacerate floral parts and suck sap resulting in brown spots. Infested flowers give sickly and faded look. Lesions cause flower fall, inferior fruits and loss in yield. Attack on tender leaves causes necrotic silvering, curling, deformation and withering.

1) Leaf Curl
Taphrina deformans
Disease Symptoms
• Initially yellowish to reddish areas appear on leaf blade of young leaves in the spring.
• These areas progressively thicken and pucker along the midrib causing the leaf to curl.
• Infected leaves often develop red to purple color. Later on white to silvery coating of spores develop on the upper leaf surface and the affected leaves become crisp and brittle.
• Finally, infected leaves abscise prematurely or may sometimes remain attached , gradually turning dark brown on severly infected trees.
• Fruit infection is characterized by irregular, raised, wrinkled and reddish lesions.
• Infected flowers and fruits drop rapidally(Fig-1).

The word persica, along with the “peach” itself and its cognates in many European languages, derives from an early European belief that peaches were native to Persia. Alexander the Great and his armies found the peaches in Persia and brought them to Greece. Most of the peaches grown in commercial orchards today are fruits that are harvested while too firm with a seed that clings to the pulp called a “clingstone” peach. The best flavoured peaches ripen soft and the seed easily separates from the edible portion, and these are called “freestone” peaches.