eChapters

Gummosis

Phytophthora spp

Diagnostic Symptoms

• Dark water soaked large patches appear on the basal portions of the stem near the ground level.

Botany :The cabbage plant, Brassica oleracea, is an herbaceous annual or biennial vegetable in the family Cruciferae grown for its edible head. The head of the cabbage is round and forms on a short thick stem. The leaves are thick and alternating with wavy or lobed edges and the roots are are fibrous and shallow. The plant produces large yellow flowers. The densely leaved heads can range in size from 0.5 to 3.6 kg (1-8 lb) depending on variety. The plant is usually grown as an annual.

Tropical plum (Spondias mombin) also known as yellow mombin, hog plum, and java plum, is a deciduous fruit species widely spread in the tropics. This species is evaluated for its fruit as an unconventional source of vitamins A and C, which are used for making juices, ice creams and jellies. This plant also has medical importance.
 
It is a graceful tree of the family Anacardiaceae, a native of tropical America. It was introduced into India for edible fruit and also to serve as fencing. The fruit flesh (48% on  weight of fruit) contains: total solids 11.47%, protein 1.38%, fat 0.57%, acids (astartaric) 1.50%, reducing sugars 9.41%, sucrose nil, fibre 1.17%, and mineral matter 0.66%. The seeds are eaten when tender. The fruit is a good source of minerals and vitamin B1 and C.

Principle of ICP Optical Emission Spectrometry

The ICP is a partially ionized gas (mostly Ar) plasma produced in a quartz torch using a 1–2.5 kW radio frequency power supply. Samples are typically introduced into the center of the plasma as aerosols. Compared to the atomic absorption spectrophotometers, in which the excitation temperature of the air acetylene flame measures 2000–3000 “K, the excitation temperature of the argon ICP is 7000–10,000 K, which efficiently excites many elements. The solution for analysis is carried by a peristaltic pump through a nebulizer into a spray chamber, where aerosol is produced by the argon gas. The aerosol thus generated is directed into the central channel of the plasma. The plasma in ICP is generated at the end of a quartz torch by a water-cooled induction coil through which a high-frequency alternate current flows. Consequently, an alternate magnetic field is induced, which accelerates electrons into a circular trajectory. Due to the collision between the argon atoms and the electrons, ionization occurs, giving rise to stable plasma. At the core of argon plasma, the temperature is sustained at approximately 10,000 K, where aerosols are quickly vaporized. Subsequently, atomization and ionization of the sample analyte elements take place. Due to the thermic energy taken up by the electrons, they reach a higher “excited” state. When the electrons drop back to ground level, energy is liberated as light (photons). Each element has its own characteristic emission spectrum. By means of an Echelle grating, a prism, and a focusing mirror, these emitted photons at various frequencies are captured simultaneously by the suitable detectors. The wavelength of the photons can be used to identify the elements from which they originate.

Amaranthus is an important leafy vegetable and is grown all over the Indian subcontinent. Amaranthus tricolor Linn and A. blittum Linn. are the common varieties cultivated. These herbaceous annuals are a rich source of proteins, vitamins A and C, and iron. The foliage is a good source of calcium, iron, and vitamins A, B, and C. In contrast, grains are good sources of important amino acids, particularly lysine, and are rich in dietary fibre, calcium, and minerals such as iron, magnesium, phosphorus, copper, and manganese. It enhances the body’s immune system and antioxidant status while lowering blood pressure and cholesterol. Fresh leaves and tender stems are used as vegetables. Production of amaranthus is affected by the incidence of pests. Cultivated amaranth is currently infested by a total of 92 different insect pests. (Rajeshkanna et al., 2017) among which the leaf webbers and amaranthus stem weevil are the most important pests.
Biology: Black moth with dark brown wings bearing white wavy markings on wings. Eggs are laid singly on leaves. Egg period 3 to 4 days. Larval duration will be completed within a period of 2 weeks. Pupation occurs among the leaf webbings and pupal duration lasts for 10 days. Several larvae can be seen inside each leaf web.

The Tea mosquito bug : Helopeltis antonii : Miridae

The host range of this bug also includes tea, neem, moringa and guava. The attack can cause inflorescence blight, terminal drying of young shoots and heavy yield loss. The adult is a reddish brown bug with black head, red thorax, and black and white abdomen. The easiest identifying character for this pest is a pin like process on the scutellum mid dorsally on the thorax. It is reddish brown, erect and knobbed, and would seem as a pin inserted into the scutellum.

23.1 Introduction

An organism or individual having more than two basic sets of chromosomes is called polyploid and the condition is known as polyploidy. Polyploidy is an important tool to increase genetic diversity by altering the chromosome number (2x) and consequently the number of genes within a single cell. Polyploidy has been one of the important mechanisms in the evolution of many cultivated crop plants.

23.2 Types of Polyploidy

23.2.1 Autopolyploidy

The condition that arises due to multiplication of the same chromosomes of a single species is known as autopolyploidy (also called ‘simple polyploidy’ or ‘single species polyploidy’). Autopolyploids have generally larger leaves, stem and other vegetative parts and flower, fruit and seeds than their normal diploids.

Star gooseberry also known as Otaheite gooseberry   (Phyllanthus acidus Skeels) is an important underexploited fruit of family Euphorbiaceae. Phyllanthus distichus Muell. Arg., Phyllanthus acidissimus (Blanco) Muell. Arg., Cicca acida Merr., Cicca disticha L. are the synonyms of star gooseberry. Food value of star gooseberry / 100g of edible portion is given below.

Carrot

Genetic Resources

Wild carrot (Queen Anne’s Lace) grows in emperate region around the world but the extent of genetic variability in wild population has not yet been evaluated in Daucus carota or related species. Constance (1971), Heywood (1983) and Mathias (1971) have contributed much to our understanding of Umbelliferae systematics, but relatively little carrot germplasm has been collected for distribution. The cultivated carrot, Daucus carota L, intercrosses freely with almost all the wild forms. Although, no incompatibility has been observed but protandry is the main reason for cross-pollination. However, there is no barrier for selfing. Carrot variety Brasilia is resistant to nematode, Meloidogyne incognita, while species Daucus carota subsp. hispanicus has resistance to other nematode, M. hapla (Simon, 1993). The genetic material, resistant to disease and pest of carrot, which can be used for developing hybrids for abiotic stresses, are given in Table1.

24.1 Introduction

When crosses are made between two different species of a genus or between two different genera, they are known as distant hybridization (also called wide hybridization). It includes both interspecific and intergeneric hybridization. Thomas Fairchild (1717) was the first man to do distant hybridization. He produced a hybrid between two species of Dianthus, viz., D. caryophyllus and D. barbatus (Carnation and Sweet William). Intergeneric hybrid produced by Karpechenko, a Russian scientist, in 1928 is Raphanobarssica. It is the amphidiploid of cross between radish (Raphanus sativus) and cabbage (Brassica oleracea var. capitata). Unfortunately, it had roots like cabbage and leaves like radish. Triticale was produced by Rimpau in 1890 itself. It is an amphidiploid obtained from a cross between wheat and rye (Triticum and Secale). Another example is Saccharum nobilisation involving Saccharum officinarum, S. barberi, S. sinensis, S. spontaneum. Wide hybridization has been used in the genetic improvement of some crops. It is an effective means of transferring desirable genes into cultivated plants from related species and genera.

25.1 Introduction

The method of selection in which a gene/QTL (Quantitative Trait Locus) is selected on the basis of the genotype of the molecular marker (also called DNA marker) linked to this gene/QTL is known as marker-assisted selection (also called marker-aided selection). The idea of marker-assisted selection (MAS) was first advocated by Tanksley (1983). MAS can be used in combination with the conventional breeding methods or novel breeding schemes could be devised to take full advantage of the marker data. MAS has been widely used for introgression of the desired genes and QTLs using backcross programmes.

25.2 Marker-Assisted Backcrossing (MABC)

The backcross programme based on molecular marker is usually called marker-assisted backcrossing (MABC). MABC has three activities: (a) foreground selection, (b) background selection and (c) recombinant selection.

25.2.1 Foreground Selection

The use of molecular marker to select the gene/QTL being introgressed is known as foreground selection. The objective of foreground selection is to select the target gene, i.e., the gene being introgressed, without phenotypic evaluation for the trait governed by the target gene. Foreground selection for a gene/QTL will be highly desirable in a variety of situation, some of which are listed below:

Purple blotch

Alternaria porri

Diagnostic Symptoms

• Disease symptoms occurs on leaf and flower stalks.

Beverage is a drinkable product which includes all drinks fermented or unfermented, sweetened or unsweetened. It may be fruit based or non-fruit beverage. Fruit based beverage is the fruit juice that has been considerably altered in its composition before consumption e.g. drink, squash, nectar etc. In this chapter, preparation of RTS drink and squash has been discussed.

1. PREPARATION OF READY-TO-SERVE (RTS) DRINK FROM FRUITS

Theory: RTS is a type of fruit beverage which contains at least 10% of fruit juice and 10 degree Brix as Total Soluble Solids (TSS) with 0.3% acidity. It is not diluted before serving, hence it is known as ready-to-serve beverage. It can be prepared from fresh/preserved pulp/juice of various fruits like mango, litchi, apricot, guava, lemon etc.

26.1 Introduction

We have already discussed the basics of tissue culture techniques in Chapter 2. Plant tissue culture techniques in combination with recombinant-DNA technology are essential requirements for development of transgenic plants (will be discussed in next chapter). However, tissue culture techniques like anther, pollen, ovule and meristem culture can themselves be used for improvement of different traits or as an aid to conventional breeding methods. In recent years, isolated microspore culture has been preferred as a breeding tool and an experiment system for various genetic manipulations. Besides, using protoplast fusion and hybrid embryo rescue, distant hybridization has been successfully achieved in many crops. Protoplast fusion technique can be used for the transfer of cytoplasmic male sterility from one species to another in very short duration. Somaclonal variation generated during tissue culture can also be utilized for recovery of variants showing disease resistance or other desirable characters.

Leaf spot

Colletotrichum capsici

Diagnostic Symptoms

• Initially oblong brown spots having about 4-5 cm in length and 2-3 cm in width with grey centres surrounded with yellow hallo are found on the leaves .

Stem gall

Diagnostic Symptoms

• Symptom appears in the form of tumor-like swellings of leaf veins, leaf stalks, peduncles, stems as well as fruits.

• Infected veins show a swollen hanging appearance to the leaves.

I am happy to note that the Indian Agricultural Research Institute, a premier national institute for agricultural research is celebrating the 100th year of its establishment. It is indeed quite fitting that JARI has chosen to celebrate this occasion by organizing a seminar on current scenario in temperate horticulture in Himachal Pradesh which is the second highest producer of temperate fruits in the country, I, therefore consider myself to be privileged to be a key speaker, and express my appreciation and gratitude to the organizers for giving me this honour and opportunity in this very important event.
 
The varied climatic and soil conditions in India provide enormous scope for cultivation of wide range of tropical, sub-tropical and temperate horticultural crops, The production of tropical and sub-tropical horticultural crops is confined to the plains, coastal and root hills of Indian mountain~ whereas, the temperate horticulture is monopoly of the hilly regions of the country. The production of temperate fruits in the country is spread over some fifteen states and union territories situated in the following regions.

1.1 WHAT IS PLANT PROPAGATION?

Propagation of plant is defined as multiplication and perpetuation of new individuals from a selected plant having all the characters of the original one. It is the process of increasing the number of plants of a particular species or cultivar. It refers to the multiplication of an individual plant or group of plants, which have specific value to mankind. New plants or new individuals are required for establishing new plantings/new gardens/new orchards.

Processed fruit and vegetable are considered as staple food products throughout the world, and are becoming more popular with the increase of the global urban population. As a result, demand for processed fruit and vegetable products tends to increase with population growth in the world. There is strong demand for processed fruits and vegetables in the developing world over the past few years. In poor countries, people consume less fruits and vegetables due to the relatively high prices. All forms of preserved fruits and vegetables are available only to the urban elite people. But rural mosses producing more than 90 % of these fruits and vegetables are usually deprived of their uses.

Demand of Processed Fruits and Vegetables

Demand of processed fruits and vegetables is increasing in the developing as well as under developing countries of world. The following reasons are responsible for day by day increasing demand of processed fruits and vegetables.

After harvesting the quality of fruits and vegetables begins to diminish and products is edible for only a limited time then products begin to spoil or rot. Losses occur during harvesting and handling of fruits and vegetables can be minimized by proper techniques but processed food spoilage is bit difficult to control and stop after infection and contamination of microorganism.

Spoilage

Spoilage is deteriorative process which results reduction in quality of food (fruits and vegetables) which become inedible. The changes in food that cause it to lose its desired quality and eventually become inedible is called food spoilage or rotting. After harvesting, the quality of fruits and vegetables begins to diminish and product is edible for only a limited time. The deterioration and spoilage of fruits and vegetables may occur at different ways.

The losses in harvested products begin immediately after detachment of products from their parental plants. After some time, theses products begin to spoil or rot. Spoilage can be defined as the deteriorative process which renders the food inedible or results in reduction in quality. Spoilage of fresh fruits and vegetables usually occurs during storage, transportation and during processing. They also get contaminated with spoilage organisms either from each other or from the containers. Mechanical injuries during harvesting and transportation further aggravates the deterioration process.