eChapters

The cultivation of pineapple, Ananas comosus is prevalent in Kerala, Andhra Pradesh, Bihar and North eastern parts of the country. It is one of the choicest fruits all over the world because of its pleasant taste and flavour. Pineapple is a good source of vitamin A and B and fairly rich in vitamin C and minerals like calcium, magnesium, potassium and iron. It is also a source of bromelin, a digestive enzyme. In addition to being eaten fresh, the fruit can also be canned and processed in to different forms. The description of some of the major pests infesting pineapple are given hereunder:

Mealy bug, Dysmicoccus brevipes (Cockerell) (Pseudococcidae: Hemiptera)

It is a polyphagous pest and besides pineapple it infests banana, sugarcane, citrus, coffee and long pepper. These are small, oval and soft bodied sucking insects. The eggs are pink in colour but remain inside the female body. The first stage nymphs are called crawlers which moves to find a suitable spot for sucking of cell sap, thereafter they settle at a particular place. The adult is elliptical and bears 17 pairs of wax filaments (Plate 10h). The colour of the pest is pink but looks white due to white waxy covering. The mealy bug first infests root and later they are found

Mealy bug: Dysmicoccus brevipus: Pseudococcidae

Mealy bugs are major pests of pineapple in India. They can attack roots and aerial parts. Colonies of reddish –white mealy bugs infest roots, crown, and fruits and suck sap. The leaves change in colour from green to red or pink and the margins reflect inwards and leaf tip starts drying. Severely infested plants become stunted and bear only small fruits. The attacked plants should be drenched with an insecticide solution of contact insecticides like Quinalphos or Dichlorvos or Chlorpyriphos@ 0.05% concentration, in between the fronds and allowed to drip down to reach the roots. Addition of liquid soap @4 ml per litre or 4 g of soap powder per litre is a must to get the best results.

Pistacia integerrima Stewart (Pistaceaceae) is an ethnobotanically important tree native to Asia. Pistacia integerrima is a species of pistachio tree native to Asia, commonly called zebrawood or the crab’s claw. It is often classified as Pistacia chinensis ssp. integerrima.

Pistacia integerrima, commonly known as kakra shingi, is a moderate-sized deciduous tree, up to 18 m in height, with a short stout bole found in the Himalayas from Indus to Kumaon. Hard, horn-shaped, rugose, hollow galls like excrescences are formed on the leaves and petioles of the plant by an insect of Pemphigus species. Dry powdered galls have a very astringent and slightly bitter taste and terebinthine odour. This tree is also used as a rootstock in the cultivation of commercial pistachios

Morphological characteristics

It is a moderate sized deciduous tree with rough grey bark. Leaves are 15-23 cm long with or without a terminal leaflet. Leaflet is stalked, 4-5 sub-opposite pairs, lanceolate, coriaceous, entire and arched. Flowers are greenish-yellow or brownish in colour, dioecious, 0.2 cm diameter, reddish in lateral, puberulous panicles, appearing with or just before the young leaves.

The term rare amino acid is misleading in some respects. It refers to all those amino acids that are not incorporated into proteins. We already got to know some of them like ornithine or citrulline that are rather common intermediates of the basic metabolism. Roughly 220 different structures are known, most of which occur in plant cells in a free state though glutamate-, oxalate- or acetyl- derivatives can also sometimes be found.

2.1 Introduction

Dear students, you shall be taught plant biotechnology during the third semester in the course ‘Elementary Plant Biotechnology’. But, for understanding of non-conventional breeding methods/techniques you should acquire some knowledge of basic plant biotechnology. Hence, in this chapter plant biotechnology is introduced to you in brief.

2.2 Definition

The term ‘biotechnology’ stems from fusion of ‘biology’ and ‘technology’. It was coined by Karl Ereky, a Hungarian agricultural engineer, in the beginning of 20th century. According to him, all processes used to yield finished products from raw materials with the help of living organism come under biotechnology. It may be defined in number of ways. However, in simple terms, biotechnology may be defined as ‘the controlled use of biological agents, such as microorganisms, or cellular components, for beneficial use’ (U.S. National Science Foundation).

8.1 Introduction

In pre-historic times, people lived as hunters and gatherers. Then, gradually they began to produce the crops they ate on piece of land, and farming was born. Wild plants have certain traits that keep them protected and productive without human intervention. However, most of them are not desired for food or other use by humans. By spontaneous mutagenesis and hybridization, occasionally variant plants were found that lacked some of the undesired traits, such as bitter taste, thorns, or had particularly attractive features, such as larger fruits and more regular tuber shape. Consequently, as time passes such variation was picked up by humans by selection of such variants, keeping and advancing them. Thus, plant domestication is the process of bringing wild species under human management. In other words, plant domestication is the process by which genetic changes (shifts) in wild plants are brought about through a selection process imposed by humans. It is a method of plant breeding in the sense that, when successful, it provides domestic types that are superior to ones previously available.

Pre-historic man domesticated virtually all of our present-day crops. But, domestication of wild species continues even today and is likely to continue for a long time in the future. For example, in many countries there is an increasing emphasis on bringing forest trees producing timber, etc. under human management. A similar trend is seen for medicinal plants and plants producing specific compounds of interest, e.g., hydrocarbons, oils, etc. Kala jeera (Bunium persicum), a perennial spice, was domesticated during 1990s in Himachal Pradesh; it is being cultivated as an orchard crop. One important aspect of domestication at present is the use of particular genes from wild relatives in the improvement of cultivated species. When a plant breeder transfers one or a few desirable genes from a wild relative to a cultivated type, he is, in a sense, domesticating the wild species in part.

9.1 Introduction

The sum total of genes in a plant species is called as plant genetic resources (also called germplasm, gene pool, or genetic stock). In other words, plant genetic resources refer to a whole library of different alleles of a plant (crop) species. Germplasm is the lifeblood of plant breeding without which breeding is impossible to conduct. It is the genetic material that can be used to perpetuate a species or population. It not only has reproductive value, but through genetic manipulation (plant breeding), germplasm can be improved for better performance of the crop. Germplasm provides the materials (parents) used to initiate breeding programme. Sometimes, what a plant breeder does is to evaluate plant genetic resources and make a selection out of existing biological variation. Promising genotypes that are adapted to the production region are then released for cultivation by the farmers. Other times, a plant breeder generates new variability by using different methods such as hybridization, mutagenesis and more recently gene transfer. This base population is then subjected to appropriate selection methods, leading to the identification and further evaluation of promising genotypes for release as cultivars. When a plant breeder needs to improve crop plants, he has to find a source of germplasm that would supply the genes needed to undertake the plant breeding programme. To facilitate the use of genetic resources (germplasm), germplasm (gene) banks are given the responsibility of collecting, evaluating, cataloguing, storing and managing large numbers of germplasm. This strategy allows a plant breeder ready and quick access to genetic resources when he needs it. The fact that Sir Otto Frankel coined the term ‘genetic resources’ only in 1968 shows that the plant breeders, though aware of the gradual loss of germplasm, failed to recognize the urgency of protecting the genetic resources of crop plants prior to a point of no return.

The aromatic plants are the valuable source for flavours, fragrances and other pharmaceutical products. The aromatic plants possess odoriferous and volatile substances, which occur in the form of essential oils, gum exudate, balsam and oleo-resin. The chemical nature of these aromatic substances may be due to a variety of complex chemical compounds. Natural essential oils comprising a complex mixture of aroma chemicals, which are difficult to reconstitute in the chemical industry, fetch very high prices. India has a long perfumery tradition that dates back to over 5,000 years in Indus Valley Civilization. In the excavation of Harrappa and Mohanjodaro, a water distillation still and receiver have been recorded, whose shape resemble to the deg and bhabka currently used by attaries (traditional perfumers) of Kannauj in India (Gupta and Chadha, 1995).
Aromatic plants are very important part of agriculture and have been grown in India for their fragrance and therapeutic use from ages. Presently, several aromatic plants are in use for medication have come from our ancestors, inhabiting in different countries. The recent advances made in chemical and instrumentation technology led to the identification and isolation of principal chemical compounds diversely used in medicines, food, cosmetics, toiletries, bouquets, aerosols, paints, varnishes, insecticides etc (Arya et al., 2021). However, the perfumery and allied industries consume much larger amount of the natural fragrant material. Many of the aromatic plants are valued for naturally occurring essential oils and the bulk of the produce finds use in perfumery and the food flavouring industries.

Many types of containers are used for growing plants in nurseries. These are clay pots, plastic pots, fiber pots, wooden pots, etc. Generally, the type of container to be used for growing a plant depends upon the kind of plant, objective of growing, choice of grower, etc. With advancement of technology, the container-grown plants are widely adopted, practiced by the nurserymen. The advantages of container grown plants are they are not prone to damage during packaging and transport. These are widely used for many fruit and ornamental plants. The different types of container and their characteristic features are as follows.

• Clay pots: Well-baked earthenware pots are used for raising plants. These are available in different shapes and sizes. On the basis of shape and size; these are named by pela, parali, kundi, nand, khobada, etc. Porous nature of the clay pots permits aeration, and water movement. Pot made with clay soil and well-baked will last longer than those made with sand or loamy soils. Before using, these are dipped in water for some period to soak the water in the pot itself sufficiently. However, earthen pots are heavy in weight, possibilities of breakage during potting and repotting and hence are less durable.

ABSTRACT

Soil salinity is one of the most serious environmental issues that limit agricultural productivity. Most of the food crops belong to glycophytes and hence, they are not able to withstand salinity stress. Salt stress significantly affects the various morphological, biochemical and physiological processes of the plant which leads to poor plant growth. Therefore, there is an emergent need to find out mitigation strategies to cope with the deleterious impacts of salt stress. Plant breeding techniques, efficient resource management and genetic engineering have been employed to cope with salt stress but these were of limited success as salt tolerant trait is complex both genetically and physiologically. Therefore, using plant growth promoting bacteria seems to be a cost effective and sustainable approach for salinity stress management. Hence plant growth promoting bacteria could play a significant role in alleviating salt stress. This chapter endeavor to provide an overview of the various important mechanisms such as facilitation of nutrient uptake, production of phytohormones, ACC deaminase production and siderophore production employed by the plant growth promoting bacteria to enhance the plant growth under salinity stress.

Growth

Growth means quantitative increase in the planwt body e.g., increases in the length of stem, roots, number of leaves, fresh and dry weight of fruits etc.

Development

It refers to the qualitative changes from the initiation of growth to the death of a plant or plant parts like seed germination, formation of flowers, fruits and seeds, emergence of buds, leaves and falling of leaves and fruits.

The quantitative increase in plant body such as increase in the length of stem and root, the number of leaves etc., is referred to as plant growth whereas, the qualitative changes such as germination of seed, formation of leaves, flowers and fruits, falling of leaves and fruits is referred as development. Utilization of these substances for proper development of the plant is regulated by certain chemical messengers called plant growth substances or plant growth regulators, which in minute amounts increase or decrease or modifies the physiological process in plants. Plant growth substances are the chemical other than nutrient which required in very small amount but without which plant can not complete their physiology.

The two sets of internal factors, viz., nutrition and hormone control the growth and development of the plant. The raw material required for growth is supplied by nutritional factors which include the minerals, organic substances the protein, carbohydrates, etc.

Phytohormones: These are the hormones produced by plants which in low concentrations regulate plant physiological process. These usually move within the plants from a site of production to a site of action.

Plant growth regulators: These are organic compounds other than nutrients, which in small amounts promote, inhibit or otherwise modify any physiological process in plant.

It may be defined as any organic compounds which are active at low concentrations (1-10 ml) in promoting, inhibiting or modifying growth and development in plants. The naturally occurring (endogenous) growth substances are commonly known as plant hormones, while the synthetic ones are called growth regulators.

Plant hormones: It is an organic compound synthesized in one part of plant and translocated to other parts, wherein very low concentration causes a physiological response.

The plant hormones are identified as promoters (auxins, gibberellin, and cytokinins), inhibitors (abscisic acid and ethylene) and other hypothetical growth substances (Florigen, death hormone, etc.).

Plant growth regulators are defined as chemicals other than nutrients and vitamins which regulate (or) modify the physiological process ofthe plant. A plant hormones or phytohormones are chemical substances which are naturally produced by plant in specific organs and are translocated from site of synthesis to the site of action. They bring about specific physiological response, even in very low concentration. The quantity of synthesis of these hormones differ from plant to plant, plant internal and external factors. They are readily absorbed and these chemicals move rapidly through the tissues when applied to different parts of the plant. A plant growth hormone may be termed as a plant growth regulator, but not vice - versa, since other than natural plant hormones, plant growth regulators are synthetically manufactured chemicals.

Plant growth regulators have a diverse chemical composition. Based on the general response the chemical mediates in the plant system, they are classified as growthpromoters and growth inhibitors/retardants. However, a particular growth regulator may be growth promoter at a lower concentration and growth inhibitor at higher concentration.

Plant growth regulators or phytohormones are organic substances produced naturally in higher plants, controlling growth or other physiological functions at a site remote from its place of production and active in minute amounts. Thimmann in1948 proposed the term Phytohormone as these hormones are synthesized in plants (Thimmann, 1963).

16.1 Introduction

Plant introduction is the process of introducing plants from their growing locality to a new locality. Introduction of plants from a foreign country is called foreign introduction or exotic collection. Introduction from one state to another within a country is called indigenous collection or indigenous introduction. With introduction, the process of acclimatization is associated. Acclimatization is the adaptation or adjustment of an individual plant or population of plants under the changed climate for a number of generations. Plant introduction is an oldest method of plant breeding. It is used in self-pollinated, cross-pollinated and asexually propagated crops. The material of seed-propagated crops is introduced in the form of seed and that of vegetatively propagated crops in the form of cuttings or propagules. The introduced material may be a new crop, a wild relative or a new cultivar of a crop already grown in the area. There are five important sources of plant collection, namely, (1) centres of diversity, (2) gene banks, (3) gene sanctuaries, (4) seed companies, and (5) farmers’ fields.

Propagation

Plant propagation means multiplication of plant by sexual or asexual method. The success in plant propagation depends on a thorough knowledge of the growth of plants, choice of suitable method and technical skill. The propagation of plants may be done either by the gametes or from the somatic cell, tissues or organs. In other words, propagation may be done by sexual methods or by asexual methods. The details of the methods are presented below.

Plant Propagation is a technique through which multiplication or production of new individuals take place from selected propagules. The methods of propagation are broadly divided in two categories:

1. Sexual method
2. Asexual method

1. Sexual method of Propagation

In this method, plants are produced from seeds and such plants are called seedlings. Seed is considered as a dormant plant which develops into a complete plant if subjected to congenial environment.

Advantages

1. This is very simple, cheap and easy method of propagation.
2. Some species of fruits, ornamental annuals and vegetables which cannot be propagated by asexual means should be propagated by this method. e.g. papaya, marigold, tomato etc.
3. Hybrid seeds can be developed by this method.

Plant propagation is one of the important fundamental aspects since the time of Rigveda (1400 B.C.) in the horticulture industry. It refers to the multiplication or perpetuation of individual or group of plants having specific value. Agriculture began, when ancient people started domestication of certain plants by growing around them and now these are cultivated in much improved form due to continuous selection and maintenance of better plant types. During the process of civilization; many plant types were selected for food and other purposes and are classified as food crops, fodder crops, fruit crops, vegetable crops, spices and condiments, aromatic and medicinal plants, etc. Now due modern plant sciences; newer and better plant types came into commercialization for cultivation. However, to maintain their qualities; it needs their propagation to keep their original form. Thus, it indicates that plant propagation has paramount importance in the horticulture industry to supply true-to-type sapling to farmers.