eChapters

• Coconut Research Station (CRS)-1916.
• Central Coconut Research Station, Kayangulam, Kerala (CCRS)- 1947.
• Generic name (cocus) is derived from the Spanish word ‘coco’ which means ‘monkey face’.
• Coconut industry employs 10 million people.
• Monolaurin content of coconut oil has anti-HIV property.
• Dwarf coconut is self-pollinated while and tall coconut is cross-pollinated in nature.
• Fully mature nut has 30-40% coir.
• Kerala has the highest share (45%) in coconut production in India: followed by Tamil Nadu (22%) and Karnataka (12%).
• The productivity of (7608 nuts/ha) Indian coconut is the best in the world.
• India ranks no.1 in terms of coconut productivity in the world.
• In India, 9-12 months old seedlings are generally transplanted
• Coconut is derived from the Spanish word ‘coco meaning ‘monkey face’.
• Tall palms: Var. typical (Nar), most commonly cultivated in all the coconut growing areas of the world, the height of 25-30m. Long pre-bearing age of 6-10 years, cross-pollinated.

Conservation agriculture is an approach to managing agroecosystems for improved and sustained productivity, increased profits and food security while preserving and enhancing the resource base and the environment. Food and Agriculture Organisation of the United Nations (FAO) defines conservation agriculture as a farming system that promotes maintenance of a permanent soil cover, minimum soil disturbance (i.e., no tillage), and diversification of plant species.

At the outset, I need to state that I am not a horticultural specialist and whatever horticulture knowledge have, is gained on the job and I am a plant genetic resources specialist with an interest in biodiversity and have worked across Asia. Today we will be mainly talking about tropical fruits and, in particular, tropical fruit tree genetic resources. If you look at tree fruits as a group, it includes a large number of species, unlike in field crops, e.g., rice, wheat, maize, etc., where just a few species are involved in each crop. Here we are talking about a group of species under each fruit tree. While talking about them, certain generalizations have to be made. Also, there are many unexploited species which are waiting to be discovered for human usage and exploitation, and there is hardly any genetic information available about them.

Biofertilizers can directly or indirectly influence the growth of plant. The direct influence can be through production of phytohormones or making the nutrients available to plants. The indirect effect can be through management of plant pathogens through biological control. Therefore, the purposeful introduction of biofertilizer inoculants to plant microbiome represents an environmentally sound option that holds a prominent position in order to reduce the dependency on agrochemicals (Adesemoye and Kloepper, 2009; Abhilash et al., 2016; Aloo, et al., 2019).

Microbes in soil can rarely exists as single cells and survive near the plant root canopy or in bulk soils or endophytes or even on plant surfaces (Lorito, 2006). The soil microflora occurs as complex members of microbiota (Hacquard, 2015). Microbial consortia (MC) are unique mixture of organisms which respond to the environment stress and adapt to stresses due to internal beneficial interactions among the microbial community. Ecosystem’s physiological functions by microflora is carried out by more than one microbial species with the functional diversity and succession among different microbial components. The microbial balance among the different microflora of a MC will consist of a continuous shift between actively growing cells and non-dividing cells of the microbial consortia. It has been reported that different microbial populations “talk” to each other by “quorum sensing” mechanism in a given environment by exchanging specific chemical signals (Thompson, 2015). Natural microbial consortia holds many specific properties like stability, functional diversity and perform complex functions. The natural consortia have generated an interest in manpulating synthetic consortia for the benefit of application (Minty, et al., 2013).

It has been well established that the biofertilizers are beneficial to plants and are cost-effective inputs for sustainable production system. However, there are some constraints with respect to its production, which are presented below:

10.1 Production constraints

10.1.1 Raw material

Eventhough there are large number of biofertilizer formulations, only few are considered as good carrier materials for biofertilizers such as peat and lignite. Moreover, its availability in India is limited and the quality is lacking for these carrier materials. Hence, a cost effective and locally available material with increased shelf-life is the need of the hour.

10.1.2 Specificity and availability of strains

As the microbial strains used as biofertilizers are specific to soil and agro-ecological conditions, availability of specific strains for the specific host and soil edaphic factors are inadequate.

Some of the constraints in cashew production in the country which limits the productivity of cashew per unit area

• % Large area under cashew in the country is still covered with non-descript genetically inferior seedling progenies.

• % Cashew is a neglected plantation crop among the farmers and generally grown under neglected condition.

• % The land which is not suitable for other plantation crops only are available to cashew crop. Hence, the land which is available for cashew is usually eroded and degraded with poor soil fertility.

• % Farmers are not fully aware of the latest cashew production technologies due to inadequate transfer of technology.

• % Even if farmers are aware of the latest cashew production technologies, non adoption of recommended package of practices to the extent required.

• % Absence of compact and dwarf high yielding varieties, because of which high density planting cannot be adopted to realize the full potentiality of high density planting technology.

Agriculture is an economic activity that is highly dependent upon weather and climate in order to produce the food and feed necessary to sustain human life. In spite of technological improvements that increase agricultural production, weather hazards have caused significant yield reductions in some years at different regions.

This chapter introduces continuous cover forestry as an approach to managing forest ecosystems while maintaining relatively continuous canopy cover and ecological processes. It examines the concept and evolution of continuous cover forestry, its ecological foundations, and advanced silvicultural practices. The chapter considers its ecological, economic, and social benefits and discusses its relevance to climate change adaptation and sustainable forest management. Comparative perspectives with conventional forestry, global case studies, challenges, limitations, and future prospects are also addressed. The approach emphasizes maintaining forest structure, regeneration, biodiversity, and ecosystem functions while allowing appropriate harvesting and resource utilization.

INTRODUCTION

Various procedures which are used for genetic improvement of crop plants are known as breeding methods. The breeding approaches that are more commonly used for genetic improvement of crop plants are called conventional breeding methods. Following conventional breeding methods were followed in improvement of crops.

(A)Plant introduction

(B)Pureline selection

(C)Mass selection

(D)Progeny selection

(E)Synthetic and composite breeding

(F)Pedigree method

(G)Bulk method

(H)Backcross method

(I)Heterosis breeding

(J)Clonal selection

Cosmos is a flowering plant belongs to family Asteraceae. Cosmos bipinnatus is ornamentally important species grown for garden display. The word cosmos is derived from the Greek word “kosmos”, which means a balanced universe or order, harmony and often referred to as Mexican Aster. The species name is from the Latin “bipinnatus” meaning “twice-pinnate” The botanical epithet is from the Latin “pinnatus” meaning “with leaflets arranged in opposite pairs”. Cosmos flowers are produced in a capitulum. Modern varieties come with single or double flowers, picotee edges, and even furled petals in the variety Seashells. Ornamental uses of cosmos include cut flowers and as border annual in the gardens. It is a very popular flower for summer bedding. Cosmos has a pleasant aroma and attracts butterflies to the garden. Essential oil extracted from leaves of cosmos. The major constituent of C. bipinnatus contained 15-17% beta-elemene, 15-17% beta-caryophyllene, 10-21% germacrene D and 12-15% bicyclogermacrene (Menut et al., 2000).

ORIGIN AND DISTRIBUTION

Cosmos is native to scrub and meadowland in Mexico where most of the species occur, Florida and the southern United States, Arizona, Central America, and to South America in the north to Paraguay in the south.

It can also be found in natural areas in much of North America, where it is a garden escape (introduced species) and in some habitats becoming a weed. Cosmos sulphureus originates from Central America (Mexico) and northern South America, where it is still found in the wild. It has been introduced as an ornamental in many countries all over the world, in tropical Africa e.g. in Senegal, Cameroon, Sudan, Tanzania, Malawi, Zambia, Zimbabwe, Mozambique, Réunion and Mauritius. Sometimes it has escaped from cultivation and behaves like a weed, e.g. in Tanzania, Malawi, Zimbabwe, the United States and Canada. Cosmos caudatus is indigenous to tropical America. It was introduced by Spaniards into the Philippines, possibly because it was used by them as a vegetable at sea. Now it is pantropical, including Southeast Asia, where it is cultivated but also occurs in a naturalized state.

Lagerstroemia indica belongs to family Lythraceae commoly known as Crape myrtle. It it grown well in India for various landscape purposes. It is called Sawani or Shravani (Hindi), Dhayti (Marathi), Chinagoranta (Telugu), Pavalakkurinji (Tamil). Lagerstroemia a long period of striking rainy season flower colour, attractive fall foliage and good drought-tolerance all combine to make a favourite shrub or small tree for either formal or informal landscapes. It is a deciduous, multi stemmed; rounded crown; dense branching and is highly recommended for planting in urban and suburban areas.

The scientific name, Lagerstroemia, was coined in 1759 by Carl Linnaeus, who described and named the plant in honour of “Magnus von Lagerstroem”, an avid naturalist and director of the Swedish East Indies Company. Crape myrtle derives its common name from its crepe-like, crinkled petals, and the resemblance of its leaves to the true myrtle, Myrtus communis. “Crape myrtle” is a peculiarly-American term. Elsewhere in the world, “Lagerstroemia” is often used as the common name for crape myrtle (Knox, 2003).

Crape myrtle is the smaller version of Lagerstroemia speciosa, commonly known as Pride of India or Queen crape myrtle. The deciduous crape myrtle is among the longest blooming trees in existence with flowering periods lasting from 60-120 days. Crapes come in heights as short as 46 cm and as tall as 12 m. Leaves are alternate and smooth, but leaf size depends on variety. Flowers are borne in summer in big showy clusters and come in white and many shades of pink, purple, lavender and red. The bark is a prominent feature being smooth, pinkinsh-gray and mottled, shedding each year. Leaves are small and dark green changing to yellow and orange in autumn. When the leaves fall in winter, crape myrtle becomes a living sculpture. The trunk and branches of tree-form plants have an attractively gnarled, sinuous character with smooth bark. Seeds are narcotic. In Manipur, flowers and leaves are used as purgatives. Bark is stimulant and febrifuge (fever removing). Roots are astringent and used as gargle.

For crop improvement and more specifically to develop new varieties a number of plant breeding methods are available. CSIR-NBRI from very beginning selected all available techniques and standardized their practical application for all ornamental crops. All crop specific basic information was collected/generated for successful application of techniques for development of new varieties by creating genetic variability. Ornamental plant species fall into two main categories. In the first group the plants that are capable of sexual reproduction, but are commercially propagated vegetatively. The second group of plant species are the apomicts. In obligate apomicts hybridization fails to generate any variability. For development of new variety creation of genetic variability is pre-requisite. Breeder should have all up-to-date knowledge about all the available techniques and their merits and demerits for improvement and development of new varieties.

A cropping system refers to the type and sequence of crops grown and practices used for growing them. It is based on the available technologies of crop production. Cropping systems have been traditionally structured to maximize crop yields. Now, there is a strong need to design cropping systems, which take into consideration the emerging social, economic and ecological or environmental concerns for each ecosystem. The goal of a cropping system must be to conserve natural resources i.e. soil, water and sustain crop production. Conserving soil and water and maintaining longterm soil productivity depend largely on the management of cropping systems, which influence the magnitude of soil erosion and soil organic matter dynamics. Crop diversification is an important option in sustainable agricultural systems. Management of cropping systems implies management of tillage, crop residue, nutrients, pests, and practices for soil conservation. Difference between dry land and rainfed farming is as follows.

A system is a set of components that are interrelated and interact among themselves. A system may be natural, social or artificial. Natural systems consist
of all the materials both physical and biological and are independent of human beings. Our role in relation to natural systems is to try to understand these
systems and make use of them as per our needs. 

Crossandra belongs to family Acanthaceae. It is also known as Kanakambaram in Tamil or Kanakambara in Kannada and Fire cracker in English because of cracking sound during opening of seed pod. Crossandra is derived from Greek word “krossoi” meaning fringe and “aner” meaning male i.e. fringed anthers. Crossandra is an evergreen shrub and one of the important loose flower used for adornment. The flowers are commonly grown for flower adornment in the form of garlands, venis and gajras. Though it is not fragrant, flowers are very popular because of its attractive bright colour, light weight and good keeping quality. These are used for making garland, either alone or in combination with jasmine flowers. Using crossandra flowers in combination with jasmine is becoming increasingly popular in India, particularly in southern parts, because the jasmine flowers provide colour contrast and the desired fragrance. Crossandra varieties show a remarkable range of colours, varying from orange, pink, red, yellow and double coloured blue-type with white throat.

ORIGIN AND DISTRIBUTION

Crossandra is native to Indo-malaya region. They are all native to sub-tropoical regions including India, Southeast Asia, Africa, and Madagascar.

Crossandra Salisb is a genus of about 50 species which are shrubs or herbs from Tropical Africa, Madagascar and Arabia, where it is grown as a perennial shrub. Crossandra undulaefolia Salisb. (Syn C. infundibuliformis Nees) is a native of East Indies. However, it is sometimes considered to be native of south India and Ceylon. C. guinensis is native of east Africa while C. nilotica has its origin in east Africa and Mozambigue. C. flava is a native of tropical west Africa.

The crossandra plants are distributed in tropical as well as subtropical regions of the world such as south Asia, South America, South Africa and Madagascar. In India, it is commercially cultivated in southern states of Karnataka, Tamil Nadu and Andhra Pradesh (Singh, 2006).

Multipurpose trees and shrubs are defined as all woody perennials that are purposefully grown to provide more than one significant contribution to the production and/or service functions of a land-use system that they occupy. In agroforestry systems, different species of trees and shrubs can be planted with many types of crops in a variety of patterns. Thus, it is required to know about the methods of propagation and nursery raising, planting and other silvicultural management practices along with the diverse uses of multipurpose trees and shrubs of tropical and subtropical areas before their selection for forestry and agroforestry activities. It is important to select the most suitable tree species since it is not easy to replace them once they have been planted.

MANGIUM (Acacia mangium)

Acacia mangium is a single-stemmed evergreen tree that grows to 25-35 m in height and up to 60 cm in diameter. The bole is usually straight, often fluted near the base, free of branches for up to half its height. Mangium is native to Australia, Indonesia and Papua New Guinea. However, it tolerates varied site conditions and has adaptability to different planting objectives. Mangium shows most vigorous growth on well-drained, fertile soils in high rainfall areas in the humid tropics. It is valued for its rapid growth and has been planted throughout the humid tropics and is a major plantation species in the Asia-Pacific. Provenances from Papua New Guinea consistently show better growth in height and diameter.

Cyclamen (Cyclamen persicum Mill.), belonging to family Primulaceae, is cultivated throughout the Temperate Zone. Many people have enjoyed the charming plants as potted and/or garden plants. The cyclamen is one of the most famous and important commercial ornamental plants in many countries. It is commonly grown for its flowers, both outdoors and indoors in pots. It is used on a terrace, in flower boxes, in hanging baskets or in beddings. Several species, particularly Cyclamen hederifolium, are hardy and can be grown outdoors in mild climates such as Northwest Europe and the Pacific Northwest of North America. The cyclamen commonly sold by florists is C. persicum, which is frost-tender. Selected cyclamen cultivars can have white, bright pink, red or purple flowers. The use as cut flower is not important part of cyclamen production (Grey-Wilson, 2002), but not rare in Europe, especially in Germany. Some cultivars for cut flower production were bred in Europe, but cut flower cyclamen production is not popular in USA and Japan. Its popularity as pot plant led to many studies on the group, including cytology (Bennett and Grimshaw, 1991), hybridization (Gielly et al., 2001 and Grey-Wilson, 2002) and phenology (Debussche et al., 2004).

ORIGIN AND DISTRIBUTION

Cyclamen originated from extreme eastern Mediterranean region and naturally grows in countries such as Palestine, Syria, Israel, Greece, Turkey, Tunisia or even Mediterranean islands: Rhodes, Cyprus and Sicily (Grey-Wilson, 2002). Cyclamen was introduced in Europe at the end 16^th century, beginning of the 17^th century, passing first through France. Somewhat neglected in the following century, the cyclamen became fashionable again in France in the 1900s. But since 1860, the first variants of the botanical or “wild” cyclamen appeared in England, then in Germany, with much bigger flowers and with varying colour shades.

Cymbidium is a genus in the orchid family Orchidaceae. It was first described by Olof Swartz in 1799. The name is derived from the Greek word “kumbos”, meaning “hole”, “cavity”. It refers to the form of the base of the lip. The flowers are long-lasting, both on the plant and when cut large attractive and available in a wide range of colours. Smaller plants are now coming into vogue as decorative pot plants. These have smaller flowers but they are as desirable as the standard varieties and often more acceptable in modern homes. The popularity of miniature cymbidium is now spreading from Asia to the worldwide orchid community. These ancient flowers have been treasured in numerous societies for nearly two thousand years. Many orchid lovers are most charmed by its fragrance and form rather than its petite size.

ORIGIN AND DISTRIBUTION

Cymbidiums figure in the earliest historical records of human association with orchids from China and Japan. Cymbidium native of the monsoonal forest foothills of the Himalayas with the warmer growing Asiatic species from the tropical lowland monsoonal forests. The species come from the Himalayan regions of India and Nepal running through China and Japan, Indo-China down to Malaysia to Australia. This genus is distributed in tropical and subtropical Asia such as northern India, China, Japan, Malaysia, the Philippines, and Borneo and northern Australia. The larger flowered species from which the large flowered hybrids are derived grow at high altitudes. They have been cultivated for thousands of years especially in China. Cymbidiums became popular in Europe during the Victorian era. One feature that makes the plant so popular is the fact that it can survive during cold temperatures as low as 7^oC. Originating in temperate and tropical parts of India, Nepal, China, Japan and down to Malaysia and Australia, cymbidiums are probably the most widely grown of all orchids because of their ease of cultivation and long-lasting flowers. From the 40-50 species, thousands of hybrids have been bred with flowers ranging in colour from white, yellow and orange to pink, red, brown and green, and varying in size from 5-10 cm across. There are several species existing in the Indian forest area. Several species are existing in the forest of Nagaland (Changkija et al., 1992), some of them are given in Table 1.

Cytogenetics helps in solving intricate problems of evolution of economic plants and their relationship with relevant wild ancestors. Ornamental plants provide very interesting material for evolutionary studies. Such a study would reveal the nature of the evolutionary steps and clarify the changes that the breeding system and chromosomes underwent. The genetic and cytogenetic reasons for the diversity in ornamentals would also be unraveled. Such a study also helps to chalk out a meaningful breeding methodology for genetic improvement. A systematic programme of genetics and plant breeding of ornamental plants was started at CSIR-NBRI. The objectives of the programme were both basic or creative (experimental analysis of the causes of variation and evolution) and applied or productive (experimental synthesis of new and novel variation with better putative parents). Evaluation of colchiploids of ornamentals with different genetic systems was being carried out at CSIR-NBRI, with a view to explore the possibility of their introduction in floriculture trade. Superiority of polyploid cultivars, in general, has been the main factor, which has induced gardeners to raise artificial tetraploids. Most of the garden forms are of hybrid origin, raised over a number of years and named differently by different workers and nurserymen. More often than not, there is no authentic record of their ancestory and they show a great deal of morphological and cytological polymorphism (Khoshoo 1968, 1990, Datta and Banerji (1995). 

Dahlia (Dahlia spp.) syn. Georgina belongs to family Compositae (Asteraceae). Dahlia was named after “Professor Andreas Dahl”, a Swedish pupil of Linnaeus and author of Observations Botanicae. In India, dahlia is grown as potted plant and landscape uses but it is a poor crop as commercial flower due to shorter commercial life and its potentialities have not been exploited so far. Therefore, there is need to originate more and more new quality cultivars. Dahlias are half-hardy perennials with tuberous roots. Stems are mostly erect, branched, glabrous or scabrous. The leaves 1-3 pinnate, with slightly serrated margin are produced opposite at each node on the stem. They bear flowers on a long, stiff stems well above the foliage. Ray florets are neutral or pinnate and disc florets perfect.

ORIGIN AND DISTRIBUTION

The wild species of Dahlia are natives of Mexico and Central America, where some hybridization and selection had probably already occurred prior to their introduction into Europe at the end of the 18^th century (Crane et al., 1947 and Sorensen, 1969). The dahlia has been in Europe for over 200 years. It came from Mexico to the Botanical Gardens in Madrid towards the end of the 18^th century and was named by Abbe Cavanille in honour of Andreas Dahl, Swedish scientist-cum-environmentalist. The dahlia was introduced into England in 1803, but from a few varieties it soon had more than 300 varieties within the first 15 years. The initial named species imported into Europe were D. pinnata, D. rosea and D. coccinea. The first dahlias grown outside of Madrid were single (open-centred) and multi-ray open centre flowered, but it was not long before the horticultural growers of the day discovered the dahlia was a natural hybrid and when grown from seed, it readily changed its form and colour, Thus it has a range of different types. Further introduction, accompanied by hybridization and selection, have resulted in the production of a wide range of flower, forms and colours. Most of the garden types have been developed from D. variabilis. The first double flowered varieties were called Show and Fancy types. The show were self-coloured, ball like flowers, while the Fancy ones were multi-coloured.

During the mid 1800’s, these Show and Fancy flowers attained cult status with gardeners and several thousand different varieties were recorded. Other forms followed, in 1829 the first Anemone flowered dahlia appeared and then in 1850 the first Pompon was raised in Germany and was named after the bobble on a French sailor’s hat. The origin of the cactus and Decorative type belongs to the arrival of ‘Juarrezii’. According to the written records it was important as a piece of tuber from Mexico in 1872 to Holland. M. Van de Berg of Uttrecht received this so called species from Mexico and released stock of the variety in 1874. Subsequently, ‘Juarrezii’, named after a President of Mexico, was introduced into the UK by W. Cullingford a Vice President of the NDS and distributed by H. Cannell after 1880. Collerettes are the last form of dahlia to have been raised, that has their origin in France and is due to sporting of dahlias at Jardin Botanique de Lyon at the end of the 19^th century.