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The horticulture handbook has been developed by the DAFWA Small. Landholder Information . horticultural sections of books, newspapers and magazines. Status Of Horticulture Industry In India. 2. 1. 3 Status Of Fruit Crops. 4. Status Of Vegetable Crops. Status Of Mushrooms. Status Of Spice Crops. Horticulture has now become as lifeline of a large population in the world. Even in India, we talk largely about horticulture. Horticulture consists of several.

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The object of the present book is to set forth the essential prin- ciples of horticulture in a manner suitable for a general introductory college course. Horticulture. Horticulture PDF Books ware material is prepared as per ICAR approved syllabus for the benefit of under-graduate students already enrolled in. PDF | The book is aimed for contains 24 chapters of whole horticulture for various examinations (ASRB, NET, SET, SAUs, SRF, IARI, HO, JRF.

Typeset by: Shivangi Computers , B-Scheme, Opp. All Rights are Reserved. No part ofthis publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, scanning or otherwise, without the prior written permission of the copyright owner. The Publisher bears no responsibility for them, whatsoever. India with diverse soil and climate comprising several agro-ecological regions provides ample opportunity to grow a variety of horticulture crops. These crops form a significant part of total agricultural produce in the country comprising of fruits, vegetables, root and tuber crops, flowers, ornamental plants, medicinal and aromatic plants, spices, condiments, plantation crops and mushrooms.

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Early autumn planting enables wounded parts of roots to be healed over. The smaller the tree the more successfully can it be removed. Plant Anatomy and Morphology 23 the sap begins to move. Attention to this rule is specially important in the case of rare and delicate plants. The removal of weakly, sickly, overcrowded and gross infertile shoots is usually, however, a matter about which there can be few mistakes when once the habit of growth and the form and arrangement of the buds are known.

Winter pruning is effected when the tree is comparatively at rest, and is therefore less liable to "bleeding" or outpouring of sap. Summer pruning or pinching off the til?

The injury inflicted is less and not so concentrated; the wounds are smaller, and have time to heal before winter sets in. The effects of badly-executed pruning, or rather hacking, are most noticeable in the case of forest trees, the mutilation of which often results in rotting, canker and other diseases. Judicious and timely thinning so as to allow the trees room to grow, and to give them sufficiency of light and air, will generally obviate the need of the pruning- saw, except to a relatively small extent.

Training is a procedure adopted when it is required to grow plants in a limited area, or in a particular shape, as in the case of many plants of trailing habit. Judicious training also may be of importance as encouraging the formation of flowers and fruit. Growth in length is mainly in a vertical direction, or at least at the ends of the shoots; and this should be encouraged, in the case of a timber tree, or of a climbing plant which it is desired should cover a wall quickly; but where flowers or fruit are specially desired, then, when the wood required is formed, the lateral shoots may often be trained more or less downward to induce fertility.

The refinements of training, as of pruning, may, however, be carried too far; and not unfrequentIy the symmetrically trained trees of the French excite admiration in every respect save fertility.

Sports or Bud Variations Here we may conveniently mention certain variations from the normal condition in the size, form or disposition of buds or shoots on a given plant. An inferior variety of pear, for instance, may suddenly produce a shoot bearing fruit of superior quality; a beech tree, without obvious cause, a shoot with finely divided foliage; or a camellia an unwontedly fine flower.

When removed from the plant and treated as cuttings or grafts, such sports may be perpetuated. Many garden varieties of flowers and fruits have thus originated. The cause of their pnJduction is very obscure. Flowers, whether for their own sake or as the necessary precursors of the fruit and seed, are objects of the greatest concern to the gardener.

As a rule they are not formed until. The reproductive process of which the formation of the flower is the first stage being an exhaustive one, it is necessary that the plant, as gardeners say, should get "established" before it flowers. Moreover, although the green portions of the flower do indeed perform the same office as the leaves, the more highly coloured and more specialised portions, which are further removed from the typical leaf-form, do not carryon those processes for which the presence of chlorophyll is essential; and the floral organs may, therefore, in a rough sense, be said to be parasitic upon the green parts.

A check or arrest of growth in the vegetative organs seems to be a necessary preliminary to the development of the flower. A diminished supply of water at the root is requisite, so as to check energy of growth, or rather to divert it from leaf-making.

Partial starvation will sometimes effect this; hence the grafting of freegrowing fruit trees upon dwarfing stocks, as before alluded to, and also the "ringing" or girdling of fruit trees, i. On the same principle the use of small pots to confine the roots, root-pruning and lifting the roots, and exposing them to the sun, as is done in the case of the vine in some countries, are resorted to.

A higher temperature, especially with deficiency of moisture, will tend to throw a' plant into a flowering condition. This is exemplified by the fact that the temperature of the climate of Great Britain is too low for the flowering, though sufficiently high for the growth of many plants. Thus the Jerusalem artichoke, though able to produce stems and tubers abundantly, only flowers in exceptionally hot seasons.

The operation of forcing is based upon the facts just mentioned. By subjecting a plant to a gradually increasing temperature, and supplying water in proportion, its growth may be accelerated; its season of development may be, as it were, anticipated; it is roused from a dormant to an active state. Forcing therefore demands the most careful adjustment of temperature and supplies of moisture and light.

Deficiency of light is less injurious than might at first be expected, because the plant to be forced has stored up in its-tissues, and available for use, a reserve stock of material formed through the agency of light in former seasons.

The intensity of the colour of flowers and the richness of flavour of fruit are, however, deficient where there is feebleness of light. Recent experiments show that the influence of electric light on chlorophyll is similar to that of sunlight, and that deficiencies of natural light may to some extent be made good by its use. The employment of that light. The advantage hitherto obtained from its use has consisted in the rapidity with which flowers have been formed and fruits ripened under its influence, circumstances which go towards compensating for the extra cost of production.

The art of retarding the period of flowering in certain plants consists, in principle, in the artificial application of cold temperatures whereby the resting condition induced by low winter temperature is prolonged. The temperature of the cold chamber is varied from the freezing-point of water, to a few degrees lower, according to the needs of the plants under treatment. When required for use they are removed to cool sheds to thaw, and are then gradually inured to higher temperatures.

The chief advantages of retarded plants are: Coldstorage chambers form a part of the equipment of most of the leading establishments where flowers are grown for market.

The taste of the day demands that "double flowers" should be largely grown. Though in many instances, as in hyacinths, they are less beautiful than single ones, they always present the advantage of being less evanescent. Under the vague term "double" many very different morphological changes are included. The flower of a double dahlia, e. The double poinsettia, again, owes its so-called double condition merely to the increased number of its scarlet involucral leaves, which are not parts of the flower at all.

It is reasonable, therefore, to infer that the causes leading to the production of double flowers are varied. A good deal of difference of opinion exists as to whether they are the result of arrested growth or of exuberant development, and accordingly whether restricted food or abundant supplies of nourishment are the more necessary for their production.

It must suffice here to say that d5Juble flowers are most commonly the result of the substitution I. Such a plant must needs be propagated by cuttings. It rarely happens, however, that the change is quite complete throughout the flower, and so a few seeds may be formed, some of which may be expected to reproduce the double-blossomed plants.

By continuous selection of seed from the best varieties, and "roguing" or eliminating plants of the ordinary type, a "strain" or race of double flowers is gradually produced. In fertilisation - the influence in flowering plants of the male-cell in the pollen tube upon the eggcell in the ovule-there are many circ'umstances of importance horticulturally, to which, therefore, brief reference must be made.

Flowers, generally speaking, are either self-fertilised, cross-fertilised or hybridised. Self-fertilisation occurs when the pollen of a given flower affects the egg-cell of the same individual flower.

In the simplest instances the pollen of one flower fertilises the ovules of another on the same plant, owing to the stamens arriving at maturity in anyone flower earlier or later than the pistils.

Cross- fertilisation must of necessity occur when the flowers are structurally unisexual, as in the hazel, in which the male and female flowers are monoecious, or separate on the same plant, and in the willow, in which they are dioecious, or on different plants. A conspicuous example of a dioecious plant is the common aucuba, of which for years only the female plant was known in Britain.

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When, through the introduction of the male plant from Japan, its fertilisation was rendered possible, ripe berries, before unknown, became common ornaments of the shrub. The conveyance of pollen from one flower to another in crossfertilisation is effected naturally by the wind, or by the agency of insects and other creatures.

Flowers that require the aid of insects usually offer some attraction to their visitors in the shape of bright colour, fragrance or sweet juices. The colour and markings of a flower often serve to guide the insects to the honey, in the obtaining of which they are compelled either to remove or to deposit pollen.

The reciprocal adaptations of insects and flowers demand attentive observation on the part of the gardener concerned with the growing of grapes, cucumbers, melons and strawberries, or with the raising of new and improved varieties of plants. In wind- fertilised plants the flowers are comparatively inconspicuous and devoid of much attraction for insects; and their pollen is smoother and smaller, and better adapted for.

It is very probable that the same flower at certain times and seasons is self-fertilising, and at others not so. The defects which cause gardeners to speak of certain vines as "shy setters," and of certain strawberries as "blind," may be due either to unsuitable conditions of extemal temperature, or to the non-accomplishment, from some cause or other, of cross- fertilisation. In a vinery, tomatohouse or a peach-house it is often good practice at the time of flowering to tap the branches smartly with a stick so as to ensure the dispersal of the pollen.

The degree of fertility varies greatly according to extemal conditions, the structural and functional arrangements just alluded to, and other causes which may roughly be called constitutional. Thus, it often happens that an apparently very slight change in. In a particular country or at certain seasons one flower will be self-sterile or nearly so, and another just the opposite. Some of the most interesting results and many of the gardener's greatest triumphs have been obtained by hybridisation, i.

It is obvious that hybridisation differs more in degree than in kind from cross-fertilisation. The occurrence of hybrids in nature explains the difficulty experienced by botanists in deciding on what is a species, and the widely different limitations of the term adopted by different observers in the case of willows, roses, brambles.

The artificial process is practically the same in hybridisation as in cross-fertilisation, but usually requires more care. To prevent self-fertilisation, or the access of insects, it is advisable to remove the stamens and even the corolla from the flower to be impregnated, as its own pollen or that of a flower of the same species is often found to be "prepotent.

It is a singular circumstance that reciprocal crosses are not always or even often possible; thus, one rhododendron may afford pollen perfectly potent on the stigma of another kind, by the pollen of which latter its own stigma is unaffected.

The object of the hybridiser is to obtain varieties exhibiting improvements in hardihood, vigour, size, shape, colour, fruitfulness, resistance to disease or other attributes. His success depends not alone on skill and judgment, for some seasons, or days even, are found more propitious than others.

Although promiscuous and hap- hazard procedures no doubt meet with a measure of success, the best results are those which are attained by systematic work with a definite aim. Hybrids are sometimes less fertile than pure-bred species, and are occasionally quite sterile.

Some hybrids, however, are as fertile as pure-bred plant;". Hybrid plants may be again crossed, or even re- hybridised, so as to produce a progeny of very mixed parentage. This is the case with many of our roses, dahlias, begonias, pelargoniums, orchids and other long or widely cultivated garden plants.

In modified forms of plants there is frequently a tendency to "sport" or revert to parental or ancestral characteristics. So markedly is this the case with hybrids that in a few generations all traces of a hybrid origin may disappear.

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The dissociation of the hybrid element in a plant must be obviated by careful selection. The researches of Gregor Johann Mendel, abbot of the Augustinian monastery at Briinn, in connexion with peas and other plants, apparently indicate that there is a definite natural law at work in the production of hybrids. Having crossed yellow and green seeded peas both ways, he found that the progeny resulted in all yellow coloured seeds. These gave rise in due course to a second generation in which there were three yellows to one green.

In the third generation the yellows from the second generation gave the proportion of one pure yellow, two impure yellows, and one green; while the green seed of the second generation threw only green seeds in the third, fourth and fifth generations.

The pure yellow in the third generation also threw pure yellows in the fourth and fifth and succeeding generations. The impure yellows, however, in the next generation gave rise to one pure yellow, one pure green, to two impure yellows, and so on from generation to generation. The length of the period during which seeds remain dormant after their formation is very variable. The conditions for germination are much the same as for growth in general.

Access to light is not required, because the seed contains a sufficiency of stored-up food. The temperature necessary varies according to the nature and source of the seed. Some seeds require prolonged immersion in water to soften their shells; others are of so delicate a texture that they would dry up and perish if not kept constantly in a moist atmosphere.

In the latter case the seedling has early to shift for itself. The time required for germination in the most favourable circumstances varies very greatly. Large and well-formed seeds are to be preferred for harvesting. New York. As a rule. It will have been gathered from what has been said that seeds cannot always be depended on to reproduce exactly the characteristics of the plant which yielded them.

Arthur Johnson and MacDaniels. Biology of Plants. Many garden plants have originated solely by selection. Plant Anatomy 2nd ed. Thus the seeds of Primula japonica.

Germination is often slower where there is a store of available food in the perisperm. Plants and their structure. An Introduction to Plant Anatomy. Estrella Mountain Community College. Those most suitable for the purpose of the gardener are carefully selected for propagation. Selection Supposing seedlings to have been developed. Laurence H. The seeds should be kept in sacks or bags in a dry place. Like all organisms.

Nutrients are indispensable as plant constituents.

Such deficiency is specific to the element in question and can be prevented or corrected only by supplying this element. The survival and well-being of humans and animals depends on plant production. To do this. This is why plants and animals have several essential nutrients in common. These criteria are: A deficiency of an essential nutrient makes it impossible for the plant to complete the vegetative or reproductive stage of its life cycle.

The nutrients required are obtained by plants both from soil reserves and external nutrient sources. In agriculture. The element is involved directly in the nutrition of the plant quite apart from its possible effects in correcting some unfavourable microbiological or chemical condition of the soil or other culture medium. Cobalt Co. Available nutrients in the soil solution can be taken up by the roots. The other 13 elements are called mineral nutrients because they are taken up in mineral inorganic forms.

Sodium Na: C and H make up 95 percent of plant biomass. In addition to plant nutrients. Aluminium Al: The relative contents of N and molybdenum Mo in plants is in the ratio of 10 Beneficial Nutrients Several elements other than the essential nutrients have beneficial functions in plants. The 13 mineral elements are taken up by plants in specific chemical forms regardless of their source.

Silicon Si: The difference in plant concentration between macronutrients and micronutrients is enormous. As humans and domestic animals require several nutrients in addition to those required by plants. Although not essential. Regardless of the amount required. Plants need about 40 times more magnesium Mg than Fe.

Cobalt Co: These examples indicate the significant difference between macronutrients and micronutrients. Some of these nutrients can be of great practical importance and may require external addition: Nickel Ni: They are traditionally divided into two groups. These three elements are required in large quantities for the production of plant constituents such as cellulose or starch.

N and K make up about 80 percent of the total mineral nutrients in plants. Necrosis is a brownish discoloration caused by decaying tissue. Absorbed N is transported through the xylem to the leaf canopy as nitrate ions.

Nitrogen N is the most abundant mineral nutrient in plants. N is a part of the chlorophyll and is an essential constituent of all proteins. Deficiency symptoms can serve as a guide for diagnosing limiting nutrients and the need for corrective measures.

Chlorosis or yellowing of leaf colour can be a sign of a marginal deficiency and is often associated with retarded growth. Nutrient ions are of extremely small size.

Chlorosis is a light green or rather yellowish discoloration of the whole or parts of the leaf caused by a lower content of chlorophyll. Necrotic leaves cannot be recovered by addition of the missing nutrient. Ca and Mg together constitute 19 percent.

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Because the cells remain largely intact. Plants exhibit many shades of greenness but a medium to dark green colour is usually considered a sign of good health and active growth.

Basics of Plant Nutrition 33 used according to their functions in plant metabolism. It is responsible for the dark green colour of stem and leaves. In general. It constitutes percent of plant dry matter. Apart from the process of N fixation that occurs in legumes.

A severe deficiency results in death of the tissue. Whether the original sources of nutrient ions in the soil solution are from organic substances or inorganic fertilisers. Plant growth is markedly restricted under P deficiency.

The principal organic forms of N in phloem sap are amides. A bluish-green to reddish colour develops. It is a part of several compounds including oils and amino acids. The potential hydrogen pH. This yellowness usually appears first on the lower leaves while upper leaves remain green as they receive some N from older leaves.

As the soil pH increases. P is readily mobile within the plant both in the xylem and phloem tissues. Tillering is poor. These generally manifest as a watery edge on the. The deficiency symptoms usually start on older leaves. Because ribonucleic acid RNA synthesis is reduced.

Extremely high levels of P can result in toxicity symptoms. The toxicity results from ammonia NH 3. N-deficient plants have a short and spindly appearance.

They include prolonged growing period and delayed crop maturity. A shortage of inorganic phosphate in the chloroplast reduces photosynthesis. P from the old leaves is readily translocated to young tissue. As N is a constituent of chlorophyll.


N deficiency in plants results in a marked reduction in growth rate. With such a mobile element. As a result. When the plant faces P shortage. P is essential for growth. In a case of severe deficiency. Nitrate and ammonium ions are not present in this sap. Groundnut shells may be hollow or poorly filled as a result of incomplete kemel development.

This is the case with all nutrients that are not very mobile in the plants. Affected plants are generally stunted and have shortened internodes. Ca deficiency is seen first on growing tips and the youngest leaves. P and S in the group of least abundant macronutrients in plants. Mg and S. Ca-deficient leaves become small. The Ca-deficiency problems are often related to the inability of Ca to be transported in the phloem. Calcium Calcium Ca ranks with Mg. Magnesium Mg ranks with Ca.

K-deficiency symptoms show on the older tissues because of the mobility of K. P toxicity can result in the death of the plant. Although all growing points are sensitive to Ca deficiency. The problems occur in organs that do not transpire readily. The affected area moves inwards as the severity of deficiency increases. Kdeficient plants may lose control over the rate of transpiration and suffer from internal drought.

The general symptom of K deficiency is chlorosis along the leaf boundary followed by scorching and browning of tips of older leaves. It is times more abundant than the macronutrients P. Basics of Plant Nutrition 35 leaf tissue. Potassium K is the second most abundant mineral nutrient in plants after N. Such plants have: K is involved in the working of more than 60 enzymes. They cease growing. Ca is a part of the architecture of cell walls and membranes. Slow plant growth can be accompanied by a higher rate of respiration.

It plays a role in regulating stomatal opening and. Ca is immobile in the phloem. In very severe cases. It is involved in cell division.

Unlike N deficiency.

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It starts with the appearance of pale yellow or light-green leaves. Under low S conditions. Mg occupies the centre-spot in the chlorophyll molecule and. A typical symptom of Mg deficiency is the interveinal chlorosis of older leaves in which the veins remain green but the area between them turns yellow.

Fruits often do not mature fully and remain light green in colour. S deficiency resembles that of N. Their growth is retarded. Mg is mobile within the plants. Nodulation in legumes is poor and N fixation is reduced.

Plants deficient in 5 are small and spindly with short and slender stalks. It is associated with the activation of enzymes. The normal total S concentration in vegetative tissue is 0. As the supply of S becomes more limiting. As Mg is readily translocated from older to younger plant parts. This patte: Leaves are small and break easily. As the deficiency becomes more severe. Sulphur S is required by crops in amounts comparable with P.

Oilseed crops deficient in S produce a low yield and the seeds have less oil in them. Most plants are susceptible to high levels of atmospheric S02' Normal In many ways. It is a part of the vitamins biotin and thiamine B 1. S toxicity can occur under highly reduced conditions. Twigs become weak and leaves drop early. S is a part of amino acids cysteine. As the S status of the plant rises. S- deficiency symptoms in most cases appear first on the younger leaves.

B deficiency usually appears on the growing points of roots. B toxicity can arise under excessive B application. B-toxicity symptoms are yellowing of the leaf tip followed by gradual necrosis of the tip and leaf margins. B in a plant is like the mortar in a brick wall. B is relatively immobile in plants and. Key roles of B relate to: Its uptake appears to be a metabolically mediated. There may be cracking and cork formation in the stalks. It appears that much of the B uptake mainly follows water flow through roots.

Some workers consider it essential only for palm and kiwi fruit. Young leaves are deformed and arranged in the form of a rosette. Death of the growing tip leads to sprouting of auxiliary meristem and a bushy broom-type growth. CI-toxicity symptoms are: Chlorine Chlorine Cl is absorbed as the chloride anion Cl-. It is thought to be involved in the production of oxygen during photosynthesis.

Leaves become scorched and may drop early. Basics of Plant Nutrition 37 concentrations range from 0. Deficiency of Cl leads to chlorosis in younger leaves and overall wilting as a consequence of the possible effect on transpiration. Other symptoms are: Yellowing of the interveinal areas of leaves commonly referred to as iron chlorosis occurs. Cu-deficiency symptoms are first visible in the form of narrow. In this disorder. It plays a role in the synthesis of chlorophyll.

At maturity. It is known to activate. In cereals. In fruit trees. Cu is involved in chlorophyll formation and is a part of several enzymes such as cytochrome oxidase. In maize. It can be a problem in highly reduced rice soils as flooding may increase the levels of soluble Fe from 0. Absorbed Fe is immobile in the phloem. Fe toxicity of rice is known as bronzing. It participates in lignin formation. In severe deficiency. For efficient utilisation of chelated Fe.

Cu- toxicity symptoms are more variable with species and less established than its deficiency symptoms. As much as 70 percent of the Cu in plants may be present in the chlorophyll. Fe deficiency begins to appear on younger leaves first. Cu is a part of plastocyanin. Cu uptake is largely independent of competitive effects and relates primarily to the levels of available Cu in the soil.

Excess Cu induces Fe deficiency and. Complete leaf fall can occur and shoots can die. Cu is not readily mobile in the plant and its movement is strongly dependent on the Cu status of the plant. This is suggested by the relatively high levels of Mo in seeds. Like Fe. It is also important in N metabolism and in CO2 assimilation. It is essential for splitting the water molecule during photosynthesis.

Mo appears to be moderately mobile in the plant. Common symptoms of Zn deficiency are: In dicots. Mo deficiency in legumes can resemble N deficiency because of its role in N fixation. Molybdenum Mo is absorbed as the molybdate anion MoOt and its uptake is controlled metabolically.

Yellow spot disease in citrus and whip tail in cauliflower are commonly associated with Mo deficiency. Mo is involv.

Basics of Plant Nutrition 39 several enzymes and functions as an auto-catalyst. The mobility of Zn is low. Early work suggested that Zn uptake was passive. Mn-toxicity symptoms lead to the development of brown spots. The rate of Zn mobility to younger tissue is particularly depressed in Zn-deficient plants. Mn-deficiency symptoms resemble those of Fe and Mg deficiency where interveinal chlorosis occurs in the leaves. Mn deficiency in oats is characterised by "grey-speck" where the leaf blade develops grey lesions but the tip remains green.

Mn-deficiency symptoms are first visible on the younger leaves whereas in Mg deficiency. Some disorders caused by Mn toxicity are: It has certain properties similar to Mg. Mo deficiency can cause marginal scorching and rolling or cupping of leaves and yellowing and stunting in plants. Zn is believed to promote RNA synthesis.

Shoots may die off and leaves can fall prematurely. In lowland or wetland rice that is low in Si. The prevalent form. N2 fixation. Internodes are short. The Co content of the shoots can be used as an indicator of Co deficiency in legumes. The beneficial effects of Si on plants include increases in yield that can result from increasing leaf erectness.

Deficiency symptoms are not the same in all plants. Si is able to counteract the effects of high N. Zn toxicity can result in reduction in root growth and leaf expansion followed by chlorosis. Co is the metal component of vitamin B Co deficiency inhibits the formation of leghaemoglobin and.

It also plays a role in imparting disease resistance and is considered essential for seed development.