eChapters

1. Introduction

If we want to know what kind of plants and animals are in a particular habitat, and how many they are of each species, it is obviously (usually) impossible to go and count each and every one present. It would be like trying to count different sizes and colors of grains of sand on the beach. This problem is usually solved by taking a number of samples from around the habitat, making the necessary assumption that these samples are representative of the habitat in general. In order to be reasonably sure that the results from the samples do represent the habitat as closely as possible, careful planning beforehand is essential.

The usual sampling unit is a quadrat. Quadrats normally consist of a square frame, the most frequently used size being 20×20 m² for trees, 5×5 m² for shrubs, 1×1 m² for herbs. The purpose of using a quadrat is to enable comparable samples to be obtained from areas of consistent size and shape. Rectangular quadrats and even circular quadrats have been used in some surveys. It does not really matter what shape of quadrat is used, provided it is a standard sampling unit and its shape and measurements are stated in any write-up. It may however be better to stick to the traditional square frame unless there are very good reasons, because this yields data that are more readily comparable to other published research. (For instance, you cannot compare data obtained using a circular quadrat, with data obtained using a square quadrat. The difference in shape of the sampling units will introduce variations in the results obtained.)

1. Introduction

Horticultural crops have emerged as a cornerstone of India’s agricultural sector, wielding substantial influence over the nation’s economic landscape. Comprising an extensive range of fruits, vegetables, ornamental plants, plantation crops, spices, and medicinal herbs, this sector has witnessed remarkable growth and transformation in recent years. The significance of horticultural crops extends beyond sheer economic value, permeating various facets of Indian agriculture and socio-economic development (Ravichandra & Ravichandra 2014).The unique agro-climatic diversity of India allows for the cultivation of an unparalleled variety of horticultural produce, contributing to its global prominence as a horticultural powerhouse.

1. House Plant

The screwpines or kewda plants are characteristics of many tropical regions with long ringed trunks, bracing roots and crowns of Dracaena-like foliage. The young plants are amongst the most popular foliage plants for home decoration as the plants do not flower at early stages (Wickham, 1950). They are also grown as pot and tub specimens for green house, residence, veranda and lawn decoration where their stiff clustered foliage gives them a formal decorative character. They may be kept as indoor ornamental foliage plants in the warm and semi light places of a house. (Wickham, 1982a).

2. Fence

The plant is useful for binding the soil, so checks soil erosion and not browsed by the cattle due to its spiny leaves; hence sometimes used as fence around the crop field in the coastal districts of Odisha, Andhra Pradesh, Tamil Nadu, Kerala and Gujrat. The plants are often used for hedges as in the Casuarina plantations at Puri of Odisha (Haines, 1961a) (Fig. 17).

Cashew is one major crop of Konkan region of Maharashtra and requires comparatively less expenditure for cultivation as compared with other crops. Under normal planting density (7m x 7m), about 200 plants/ha are occupied. If the cashew grower has its own land, then for first five year of orchard establishment and maintenance, total expenditure of Rs. 47447 is come up. Year wise expenditure (first five years) on cashew cultivation per hectare is presented in Table 61.

Kewda plants are mostly propagated through vegetative means. The common propagating materials used are ground suckers. The planting materials are planted in paired-row method maintaining a spacing of 4m from plant to plant and row to row keeping a spacing of 6 m between paired rows. In a field of one hectare, a minimum plant population of 500 plants in the field and 150 plants on the field bunds with a total of 650 plants are maintained. A fertilizer dose of 30:15:15 kg NPK/ha and 4 cartloads (100 cft) of FYM/ha are applied. The planting of collected ground suckers is normally done in the field just before monsoon after thorough land preparation under rainfed condition.The earthing-up of the plants are done up to five years of planting for quick initiation of flowering at the age of 5 years after planting. During the first year, the operational cost per hectare comes to Rs.28,900/- and from 2^nd to 5^th years, it comes to Rs.6,600 per year and then the maintenance cost from 6^th year onwards comes to Rs.6,000/- per year. The details of the operational cost per hectare of kewda cultivation under rainfed condition of coastal Ganjam district is given at Table 23. Kewda plant comes to flower on the 5^th year of planting, but the annual net profit begins on the 6^th year of planting and the cumulative net profit starts on the 10^th year (Table 24). The economic viability of kewda plantations is observed from 10^th to 30^th year of planting and after 30^th year, the net profit declines. A farmer can earn an annual profit of Rs.61,000/- per hectare of kewda cultivation from 11^th to 15^th year, which goes on increasing and from 26^th to 30^th year, the annual net return reached to Rs.1,23,400/- with a cumulative return of Rs.4,04,970/- on the 30^th year of planting. Then at the age of 35^th year, it declines to Rs.1,07,800/ - and at 40^th year to Rs.87,000/- per annum (Table 24). Although the profit was calculated only on the basis of sale of flowers yield, some additional profit can be obtained from other plant parts like leaves and stilt roots. After distillation of one lakh flowers, the spent over flowers and plant parts can be utilized as fertilizer/manure by selling at a rate of Rs.1000/- per batch. In the two blocks (viz., Chhatrapur and Rangeilunda) of Ganjam district, about 7,000 women are engaged for collection of flowers, leaves and stilt roots and they prepare ropes and other household items from the roots and leaves. It has been observed that one female can prepare 12 bundles of ropes each of 12 m length and the sale rate of rope is about Rs.10/- per metre. The ropes are sent to the markets of Visakhapatnam (Andhra Pradesh) and Chennai (Tamil Nadu) for sale. The profit can also be increased by incorporating some inter-crops like Casuarina, coconut, Agasti and medicinal crops like Patchouli etc. Further, kewda can be taken on the sand dunes and waste saline land of the coastal lines, where no other crops can be grown profitably. Hence, kewda needs better attention for its extensive cultivation with a foresight on the perfume industry.

Eczema is a troublesome skin condition characterized by redness, cracking, oozing and scaling of the skin. Extremes of heat and cold and even emotional stress seem to play a part in this condition. The patient usually complains of itching and burning in the skin, especially at the night. Sores appear on various parts of the body, but most often on the hands, feet, ears and legs. Eczema may come on at any time of life and in either sex. The commoner manifestations are erythema changing to papule, vesicle, crust, scale and fissure, with serous exudation. In chronic cases, thick scales accumulate.

This is the effect of local irritation by chemical, thermal, actinic or mechanical agents in a hypersensitive individual, subject of an allergy or constitutional disabilities such as gout, chronic nephritis, rheumatism, local sepsis, dyspepsia, alcoholism, uterine disturbances also teething. In some cases heredity may be found.

Papules, vesicles and pustules with some degree of local oedema are found; exudation, crusting and scaling with inflammation of varying severity may be present. These tend to spread to the contiguous areas.

One or both cheeks of an infant or the ear, limbs or trunk are occasionally involved. In adults also similar papulo- vesicular eruptions appear. Sensations of burning, smarting, throbbing or itching are present, according to the acuteness of the process and severity of the inflammation.

Edge plant

Very low growing plants grown only for the purpose of decoration and demarcation and not for screening are known as edging. Live and inert materials used for living of borders flower beds, paths, lawn, shrubbery and herbaceous border are known as edging. Formal edgings are: Bricks, stones, tiles, concrete etc. Informal edging are: Grass verges and crazy paths made up of tiles stones etc.

The Begonia family has a tropical and subtropical distribution in America, Asia and Africa. With approximately 100 species and 10,000 cultivated hybrids, they are very important as ornamental plants.A few reports describe Begonia as edible; the highest number of these species is found in America, some in Asia, and we have only one report of an edible Begonia in Africa.

The Begonia family has a tropical and subtropical distribution in America, Asia and Africa. There are approximately 600 species in America, and the same number in Asia.

Africa, including Madagascar and the Mascarenes, has 158 reported species, one third of which are endemic to Madagascar and associated Isles (Mascarenes, Seychelles and Comoros). Only ones species, B. grandis Dryander, is widely distributed in temperate regions, extending northwards near Beijing (Forrest & Hollingsworth, 2003; Plana, 2003).

This chapter demonstrates that modern advances in horticultural crop development may benefit from not only knowledge derived from extant ethnographic groups but extinct peoples as well. More than 18,000 archaeological sites were identified, and a dozen rock shelter sites investigated in the Zeekoe Valley, Upper Karoo, South Africa. A baseline for understanding potential contribution of plants to the Zeekoe Valley diet is crucial for developing models of land use and mobility patterns for Late Stone Age (LSA) inhabitants, particularly since  ethnographically known foragers in Botswana, some 800 km to the North, are as much as 80 % depend on plant foods for their survival.  Since native foraging groups are long extinct in this semi-arid region with abundant natural springs, a rigorous investigation of botanical and ethnohistoric literature forms the groundwork for field investigations where direct ethnographic observation is no longer an option. First, edible species in the study area are identified in the literature. They are then sought on the ground with the aid of local informants whose families reside in the valley for generations. It appears as though some knowledge of local plants gained from native foragers 150 years ago or more have remained in Afrikaans families passed down from landowning parent to child. On the ground, collection and middle range experimentation were followed by basic nutritional analysis.  These measures were then used to compare foraging efficiency to measures from extant foraging groups.

While reviewing the status of education and research on medicinal plants in Bangladesh, it was found that there are 27 government and private educational institutions currently engaged in offering Bachelor or Diploma degree on Unani and Ayurvedic systems and training of traditional medicine practitioners in Bangladesh. Several other public and private universities have included different aspects of medicinal plants in their syllabus with other degrees at undergraduate and post graduate level. At present, there are 277 Unani, 201 Ayurvedic and 32 herbal drug manufacturers in Bangladesh with 6498 Unani, 4058 Ayurvedic and 537 herbal products registered by the Directorate General of Drug Administration. About 500 species of plants are identified which possess medicinal properties and are distributed throughout the country. There is no distinctive research organizations at present for conducting planned research solely on medicinal plants; though, the Bangladesh Forest Research Institute have some research programme on medicinal plants. Hamdard University- a private university is offering degree on Unani and Ayurvedic systems and conducting some research including drug manufacturing. Bangladesh Agricultural Research Institute with other public and private universities are conducting some hectic research on medicinal plants including some high yielding variety development. The Government of Bangladesh (GoB) have taken some initiatives for development of Unani and Ayurvedic medicine sector like making ‘Bangladesh Unani and Ayurvedic Practitioners Ordinance, 1983’, ‘National Drug Policy 2016’, establishment of ‘Board of Unani and Ayurvedic Systems of Medicines (BUASM)’, etc. But proper implementation of the ordnance, strengthening the activities of BUASM and taking organized research programme on medicinal plants are very much essential for having skilled professionals, quality drugs and research.

Air pollution is the major environmental problem due to rapid urbanization and industrialization. It has led to continuous deterioration of air quality in both developed and developing countries.

Air pollution is characterized by high concentrations of suspended particulate matter, oxides of sulphur and nitrogen. Air pollution has long term effects on fruit trees; when exposed to higher orabnormal levels of various air pollutants. The injury symptoms range from visible marks on foliage, reduced growth and yield to premature death of the plant. The development and severity of injury depends not only on the concentration of the particular pollutant, but also on a number of other supporting factors. These include the duration of exposure to the pollutant, the plant species and development stage as well as conducive environmental factors.

Air pollution problems: Air pollutants are injurious to vegetation can generally be classified as either local or widespread.

ABSTRACT

Senna (Cassia angustifolia), a traditional medicinal crop in Tamil Nadu warrants the modern quality guidelines viz. Good Agricultural Practices (GAP) for marketing overseas. Buyers of developed countries insist on GAP and organic certification for medicinal plants. With this in view, an experiment was conducted at Medicinal Plants Unit, Botanic Garden, Tamil Nadu Agricultural University, Coimbatore to study the effect of various biostimulants on yield and yield attributing characters to standardize the biostimulant(s) for higher yield. The treatments included different concentrations of panchakavya (2% & 4%), moringa leaf extract (2 & 4%) and humic acid (0.2 & 0.4%). The field was laid out in randomized block design. Vermicompost @ 4 t ha^-1 was applied commonly to all the plots. Spraying with the above said chemicals was done at 15 days interval from 30 days after transplanting for four times. The observations were recorded for growth a yield characters and were statistically analyzed. The treatment 2% panchakavya + 2% moringa leaf extract + 0.2% humic acid recorded the highest value of growth and yield characters like plant height (44.58 cm), number of branches (6.1), number of pods (53.0), dry leaf yield (560.8 kg / acre) and dry pod yield (6. 72 g / plant).

India has an opportunity to grow a variety of horticultural crops due to varied agro climatic conditions and thus, it forms a significant role in total agricultural produce. Though, horticultural crops occupy 8% of the cropped area, approximately 30% contribution in agricultural GDP. Horticultural crops play a unique role in India’s economy by improving the income of the rural people.

However, during the last decades onwards, the productivity of horticultural crops has been affected by many factors. One of the major reasons is climate change. Climate change is one of the most leading environmental problems which is facing the modern world and directly or ultimately to human action that changes the arrangement of the global atmosphere.

The earth climate has always changed in response to changes in the cryosphere, hydrosphere, biosphere and other atmospheric and interacting factors. It is widely accepted that human activities are now increasingly influencing changes in the global cliamte. Emission of increasing amounts of greenhouse gases, carbon dioxide, methane, chlorofluorocarbons and nitrous oxide are responsible for generating changes to global climate. These changes are responsible for rise in sea level, rainfall sequences and movement of climatic regions due to increased temperatures.

ABSTRACT

Tamarind, an economically important multipurpose tropical tree, is a species of choice for sustainable development of wasteland due to its hardy nature and adaptability to various agroclimatic conditions. However, there are very few reports on in vitro regeneration of tamarind. In an attempt to induce caulogenic response, effect of different cytokinins on nodal explants from mature trees was tested. The study extended to seedling explants, revealed that 6-Benzylaminopurine (0.08 - 44.39μM) and Zeatin (0.09 - 9.12μM) induced multiple shoots with callusing at the base of explant. Kinetin (0.09 - 9.29μM) and 6-γ,γ- dimethylallylaminopurine (2iP) (0.09-9.84μM) remained ineffective for multiplication of shoots and callusing was noted at the cut end of explant in contact of medium. Thidiazuron (TDZ) (0.09- 9.08μM) failed to induce morphogenic response and triggered dedifferentiation in the basal cut end. This led to profuse callusing in the explant and restricted morphogenesis. To avoid wound in the explant, tamarind seeds were cultured in medium containing TDZ.

Seedlings were germinated in medium with or without Thidiazuron (4.54, 9.08, 13.12, 18.16μM). Differentiation of the apical meristem to shoot was restricted and proliferation of the cotyledonary node meristem was triggered. Large number of meristematic buds appeared in a radial pattern around the node. The meristematic activity subsequently spread towards the cotyledonary bridge and also in the proximal part of the hypocotyl. These buds differentiated to form shoot primordia and subsequently to shoots in medium devoid of growth regulator. Plants developed by micrografting of these shoots on seedling derived rootstocks, survived in soil.

ABSTRACT

Attempts were made to induce variability by irradiation of axillary buds of rose cv. Folklore followed by in vitro culture. Axillary bud explants collected at different growth stages were subjected to gamma irradiation at different doses (20, 30 and 40 Gray). The in vitro induced micro shoots were sub cultured on a rooting medium (M.S. basal medium supplemented with IAA 1.00 mg/l + NAA 1.00 mg/l + activated charcoal 500 mg/l). The rooting percentage was the lowest in explants irradiated with 40 Gy. Rooting efficiency was severely affected when buds were collected at vegetative phase. Significant interaction between bud stages and gamma rays was noticed for days to root initiation and number of roots per culture. Gamma irradiation at 30 and 40 Gy significantly delayed root initiation at all stages of buds exposed. Significant reduction in number of roots/ culture, and root length was observed at higher doses of gamma exposure. The reduced rooting efficiency may be due to inhibition of cell division on account of chromosome damage.

Nature has bestowed our country with diverse agro climatic and topographic conditions ranging from temperate to humid and from sea bed to snow line. The existing climatic conditions with a plenty of sunshine, nutrient rich soil, abundant water resources and reservoir of trained manpower, enable our country to grow various types of vegetables in tropical, subtropical, temperate, alpine and desert vegetation zones in one or the other seasons during the year.

Vegetables, the cheapest and nutrient-rich food source within the economic reach of poor man, play a vital role in human diet since they provide carbohydrates, protein, fat, minerals, vitamins, fibers and phytochemicals (non-nutrient bioactive compounds), which are essential for making the body immune system strong, detoxifying carcinogens, reducing muscular degeneration and protecting the body from infectious ailments. Vegetables besides having medicinal values also play an important role in nutritional security and national economy of the country since they are quick growing and short duration, and their yield per unit area per unit time is 5-10 times higher than the cereal crops.

ABSTRACT

Bacterial wilt caused by Ralstonia solanacearum is the major constraint for cultivation of tomato in Kerala. Biocontrol of plant pathogens is becoming an important component of integrated disease management. Among the various antagonists tested against R. solanacearum of tomato, fungi were more effective than bacterial and actinomycetes organisms. Among them, Trichoderma virens, T. viride (Ozhalapathy and Vellanikkara) and T. pseudokoningii were the effective ones, recording the maximum antagonism index (AI) value of 6000 under in vitro condition. They inhibited the pathogen completely by the mechanism of both lysis and overgrowth. In pot culture study, T. viride and T. pseudokoningii and commercial Pseudomonas fluorescens gave maximum protection against wilt incidence. Under field condition, T. viride (Ozh), T. pseudokoningii and P. aeruginosa showed the lowest wilt incidence of 50.0, 58.3 and 58.3 respectively against cent per cent incidence in the control plot.

The availability of wide range of pesticides though has been responsible for increasing crop production through regulating arthropod (insect and mite) pest populations in agricultural and horticultural crop production systems but unfortunately, improper and excessive use of pesticides has resulted into a number of potential ecological problems including pest resistance, resurgence, residues in food, feed and fodder, environmental contamination, direct hazards to the users and mainly destruction of beneficial organisms including natural enemies. The most important group of natural enemies is entomophagous insects i.e. insect predators and parasites. Predatory insects are usually much larger than their prey and are generally voracious feeders that kill and eat a wide variety of insects as they grow and reproduce. Many predators are active in both their immature as well as adult stage. Insect parasites/ parasitoids are often tiny, non-stinging wasps. Parasitic wasps are free-living in the adult stage, but in the larval stage are parasitic on specific insects. The parasitic larvae eat their hosts from within, ultimately resulting in the death of the host insect. The compatibility of natural enemies with pesticides is essential as both these management strategies are important part of Integrated Pest Management programs designed to regulate arthropod pest populations and minimize plant damage.

The modern improved crop varieties are responsive to fertilizers and demand higher fertilizer application rates to sustain high grain yields. With higher fertilizer inputs, the pest problems have become prominent and endangered the yields necessitating the large scale use of agrochemicals. Some of these chemicals are purposefully released or they may be accidentally released into the environment as waste water or residues from industrial manufacturing and processing of fields.

Soil is one of the most dynamic sites of biological interactions in nature, serving as a growth medium for vegetation and as a habitat for microorganisms and thus has a major role in determining the overall quality of our environment. The physicochemical properties of soil strongly influence the growth, activities and population dynamics of microorganisms in soil and also modify the effects of chemicals on the microbial community. Microorganisms are scavengers in soil. Due to physiological variability, they degrade a variety of chemical substances including insecticides, fungicides and herbicides in soil to derive energy and other nutrients for their growth and metabolism (El- Shahaat et al., 1987; Bhuyan et al., 1993). As a result, the population density of the active microorganisms increases which favorably influences the biological transformation of nutrient elements in the soil (Rangaswamy and Venkateswarlu, 1993; Jana et al., 1998). On the other hand, there are many pesticides which exert adverse effect on growth of soil microorganisms (Martinez-Toledo et al., 1992). However, no definite conclusions can be made on the effects of different pesticides on the growth and activities of microorganisms in soil since different groups of insecticides exhibit manifold variations in toxicity. The degree to which a pesticide affects microbial population and their activities is largely dependent upon the chemical, its dosage and the particular physicochemical parameters of the environment such as soil type, temperature, water content, pH, method of application and other factors. Soil physicochemical factors are particularly important and probably account for the variations in toxic effects often seen with the same compound. Some of the soil microorganisms and soil microbial processes appear to be more sensitive to pesticides than the others. For example nitrification appears to be highly sensitive whereas N-mineralization is relatively resistant. These results reflect the diversity of microorganisms mediating these processes. The present effort has been made to review briefly the effects of pesticides on microorganisms and their activities.

ABSTRACT

Anursery experiment was conducted to study the effect of solarization, selected native antagonists viz., T. viride and T. longibrachiatum and the standard culture of T. harzianum for assesseing the growth enhancement and management of Phytophthora rot in black pepper nursery. The experiment was laid out at College of Horticulture with 20 different treatments and replicated thrice. The sprouting percentage of cuttings in different treatments was worked out at different intervals, which showed significant difference. In general, it was observed that the maximum sprouting percentage was noticed in treatments where solarized potting mixture and biocontrol agents were used. The population of soil microflora viz., fungi, bacteria and actinomycetes in different treatments were also estimated. The study indicated a fluctuation in the population of soil microbes in various treatments at different periods of observation. The observations on height and number of leaves of pepper cuttings in different treatments were recorded. It was noticed that cuttings raised in solarized potting mixture incorporated with native antagonists, especially T. viride, exerted a significant effect in increasing the height of cuttings. With regard to total number of leaves, it was also observed that addition of native antagonists in solarized potting mixture had a positive effect in increasing the leaf production. Thus, the effect of solarization enhanced the growth parameters in crop plants by making available the required nutrients. The increased growth response of plants by soil application of Trichoderma spp. may be due to the production of growth promoting substances by the antagonists. Thus, the nursery experiment revealed that, in general, soil solarization and incorporation of antagonists had a favourable effect in promoting the growth of pepper plants besides checking the Phytophthora rot in black pepper nursery.