eChapters

Botany

Cauliflower is highly cross pollinated crop due to self incompatibility. Flower is protogynous in nature. Stigma remains receptive 5 days before and 4 days after opening of the flower. The time taken from pollination to fertilization is 248 hours depending upon the temperature. The optimum temperature for fertilization and seed development is 12°C – 18°C. Bees are the major pollinators.

Method of seed production: There are two methods of seed production

1. in situ method (seed to seed method)
2. Transplanting method (Head to seed method)

For seed production, seed to seed method is recommended since the head to seed method in India has not been very successful. In seed to seed method (In situ method) the crop is allowed to over winter and produce seed in the original position, where they are first planted in the seedling stage.

Cauliflower
Cauliflower, Brassica oleracea L var. botrytis under the family Brassicaceae (Cruciferae) having chromosome No. 2n = 2x =18 is the most popular vegetable among the cole crops, particularly in Asia. It is grown in all continents of the world,= of which Asia is the leading one followed by Europe and covers small acerages in North America, South America, Africa, Australia and New Zealand. India and China together have about 60 % of total cauliflower area of the world. Cauliflower is used in different curry and fry preparations with potato, garden pea, sweet pepper and other vegetables. It contains high quality proteins and good in stability of vitamin C after
cooking. Frozen products are also prepared from cauliflower. It is rich in minerals such as potassium, sodium, iron, phosphorus, calcium, magnesium, etc.
Origin, domestication and adaptation in India
The cole crops have originated from the wild diploid species Brassica oleracea var. sylvestris mainly by mutation, human selection and adaptation. This wild species, a leafy kale-like plant which occurs in the northern shore of the Mediterranean Sea an along the lime cliffs in north-eastern England and North Sea is the progenitor of th cultivated kale and leafy non-heading cabbage. Probably kale was the first cole crop to have selected and adapted by man. From this leafy kale-like plant (Brassica oleracea var. sylvestris), other cole crops viz., kale, collard, broccoli, cauliflower and cabbage have been descended.

Cauliflower follows cabbage in importance with regard to area and production in the world. However in India Cauliflower is more widely grown than cabbage. This crop grows at a latitude 11°N to 60°N with average temperature ranging from 5- 8°C to 25-28°C. It can stand to the temperature as low as -10°C and as high as 40°C for a few days. Italy and India are the major countries growing CF on large scale. Important cauliflower growing states in India are UP, Karnataka, West Bengal, Punjab and Bihar. It is commonly grown in Northern Himalayas and Niligiri hills in south.

Origin and Distribution: Cauliflower is thought to have been domesticated in the Mediterranean region since, the greater range of variability in the wild types of B.oleracea is found there (Nieuwhof, 1969). Wild Cole warts are still found in wild state in sea cost of England and Denmark and in the North West France and various localities from Greece to Great Britain. The Cole crops, including cauliflower and cabbage have descended from a common Kale like ancestor, the wild cabbage (B.olearcea var. sylvestris L.) which is still found in western and southern Europe and North Africa (i.e, sea coasts of England and Denmark and in North West France and various localities from Greece to Great Britain). Cyprus and area around Mediterranean courts are considered to be the primary centers of origin for Cauliflower. It is also reported that cauliflower is originated from a related species. B.cretica. As per Bosewell (1949), it originated in the islands of Cyprus from where it moved to other areas like Syria, Turkey, Egypt, Italy, Spain and North Western Europe. Cornish types originated in England fallowed by temperate types originated in Germany and Netherlands in 18th century. The present Indian tropical cauliflowers developed as a result of intercrossing between European and Cornish type. In India tropical types with resistance to high temp and high rainfall conditions have been developed. Tropical types are grown in Indian plains from May to September, followed by temperate types known as snowball cauliflower.

Cauliflower (Brassica oleracea var. botrytis, 2n = 2x = 18, Family Brassicaceae, cross-pollinated, sporophytic self-incompatibility) is traditional European crop that has become widespread in Asia. As per Horticulture Statistics at a Glance-2018, published by Ministry of Agriculture and Farmers Welfare, Government of India (MAFW, 2018), during 2016, global production of cauliflower and broccoli was 25.23 million tons from 1.34 million ha with a productivity of 18.82 tons/ha. Bulk of area and production (>70%) was accounted for by China, I rank (0.52 million ha area, 10.26 million tons production, 19.73 tons/ha productivity) and India, II rank (0.43 million ha area, 8.20 million tons production, 19.0 tons/ha productivity). Other countries in the descending order were USA, Spain, Mexico, Italy, France, Poland, Pakistan and Egypt.

Within India, as per 2017-18 figures, top 10 cauliflower growing states are West Bengal (74, 000 ha), Bihar (62, 000 ha), MP (46, 000 ha), Orissa (41, 000 ha), Haryana (40, 000 ha), Gujarat (25, 000 ha), Chhattisgarh (24, 000 ha), Jharkhand (22, 000 ha), UP (18, 000 ha) and Punjab (18, 000).

Celery was grown as an aromatic and therapeutic herb by Egyptians, Greeks, and Romans. It was first grown in Italy in the 16th century after this wild variety. It was then introduced to the British Islands by the Italians and French at the end of the 17th century. It was first grown in North America in the nineteenth century. Celery’s young leaves and stem are high in minerals, vitamins, and proteins, making it one of the most essential therapeutic plants. Celery oil has a pleasant aroma. This aromatic oil aids in the efficient functioning of the human brain. On an area of roughly 5000 acres, the crop is grown primarily in Punjab (Jallandhar, Gurdaspur, and Amritsar districts), Haryana, and western Uttar Pradesh (Ladhwa and Saharanpur districts). Punjab provides almost 90% of the overall production

Plant body consists of numerous microscopic box like components called cells. The word cell has been derived from the Latin word cellula, meaning a small room. The descriptive term for this smallest living biological structure was coined by Robert Hooke in a book he published in 1665. When he compared the cork cells, he saw through his microscope to the small rooms monks lived in. The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life, which is classified as a living thing and is often called the building block of life (Maton et al., 1997). It is defined as a mass of protoplasm surrounded by a membrane- the plasma membrane- within which complicated chemical reactions are going on.

Crop Domestication

Domestication can be loosely defined as the process of bringing of a wild species under the management of man. Domestication is the process by which genetic changes (or shifts) in wild plants are brought about through a selection process imposed by humans. Because of the role of humans, the process results in characteristics that are beneficial to humans but some that would be disadvantageous for plants in their natural habitats. It is an evolutionary process in which selection (both natural (frost tolerance) and artificial (large attractive fruits)) operates to change plants genetically, morphologically, and physiologically. 

India has a wide agroclimatic range i.e. temperate, subtropical and tropical, enabling to achieve horticulture diversification. India is second in fruit and vegetable production at global level. The percentage share of horticulture output in agriculture has become 33%, (Horti statistics, 2018). However, productivity in most of the horticulture commodities is very low below world productivity, as we have not concentrated intensively on some major aspects to achieve competitiveness in horticulture for expansion in international trade.

India has potential to lead the world in horticulture. Horticulture is mostly concerned in different aspects of human beings such as provision of nutritious food to achieve a balanced diet; rural employment, integral part of rainfed and dry land areas, wealth generation through the activities of production, processing, marketing, servicing, and related sectors, economically important in export related activities and associated with all the elements of the supply chain etc. 

There are several difficulties involved with consuming and storing microgreens. Addressing low shelf life and putting into practice efficient postharvest management for microgreens provide formidable challenges for researchers. It's critical to comprehend any relationships that might exist between spoiling and human pathogen contamination. Research has indicated that microgreens including basil, lettuce, parsley, melons, and spinach can have infections from pathogens during the seed-to-harvest stage (Alegbeleye et al., 2018). Growing environments that support the growth or transfer of microorganisms, processing techniques that expose the crop to contaminants from people or animals, and physiological traits of the plant that facilitate contact and binding with microorganisms are some of the factors that contribute to this risk (Maluin et al., 2021). Because external fertilizers and manures are applied sparingly, there is little contamination even though microgreens are protected from pests and insects by controlled surroundings.

ABSTRACT

Atotal of 45 Gram positive, spore forming and rod shaped bacteria identified as Bacillus species were isolated from the rhizosphere of Chickpea plants. They were studied for their interaction with root borne fungal pathogens was studied using spot test method. Isolates CBS 29, CBS 113, CBS 123, CBS 132, CBS 153 and CBS 155 inhibited the growth of four or more fungi with inhibition zones varied from 1-5 mm. Two isolates CBS 153 and CBS 155 produced siderophores on CAS supplemented agar medium. Further inoculation of these Bacilli on seeds of Chickpea cultivar C235 and H8618 showed inhibitory, stunting or stimulatory effects on plumule and radicle growth depending upon cultivar, bacterium used and stage of seedling growth. Studies on co-inoculation of these isolates with Mesorhizobium and their plant growth promoting activity are being carried out. These co-inoculation studies are important areas of exploitation to improve crop productivity.

Sauropus androgynus, also known as katuk, star gooseberry, or sweet leaf, is a tropical shrub that is used as a leaf vegetable in some areas. It’s known as Chinese Malunggay in China, and madhura cheera in Kerala, India. It has several upright stems that can grow up to 2.5 metres tall and dark green oval leaves that are 5-6 cm long. It’s known as ‘Multivitamin Greens’ because of its great nutritional value. Chekurmanis, which may be found in practically every household kitchen garden in Kerala, has not been cultivated for commercial use on a significant scale. As a result, there are no data on the area and production of these vegetables.

The chemical composition of seeds is basically determined by genetic factors and varies among different species and seed parts (Table 1). However, it is influenced by environmental and cultural practices.

In the previous chapter the physical methods of fruit and vegetables processing and preservation have been discussed. The present chapter deals with chemical method of fruit and vegetable preservation. In this method of preservation of fruits and vegetables, chemicals as preservatives are used to prevent the spoilage of fruit and vegetable products. These preservatives react with food (produce) constituents or microorganisms and create unfavourable conditions which hinder growth, activities and multiplication of microbes responsible for spoilage of food products. These chemical agents have maximum permissible limit of their use as law. They can be classified into two classes class I and class II.

Class I: Sugar, Salt and Oils

Class II: Sodium benzoate, Potassium metabisulphite (K M S) and Sorbic acid

Very little is known about the basic principles governing the chemistry of flavour or fragrance. In English, the term aroma chemicals is used for both fragrance and flavour compounds. Any compound with a sufficiently high vapour pressure will have an odour and this is normally of the molecular weight of around 300, a relatively low polarity granted (Frater et al., 1998). Generally only compounds with pleasant smell are considered to fall under the realm of fragrance chemistry, but purified individual components from a mixture may have a malodour. Almost all ancient civilizations had their tradition of making fragrances from natural materials, mostly of plant origin, but also of animal origin – these are mostly essential oils, exudates, balsam and resins (Arctander, 1969).
 
It was in the latter half of the 19th century that synthetic fragrance chemicals were experimented upon and brought into the market, examples being coumarin (Fig. 1) (in the year 1866), salicylaldehyde (Fig. 2) (1876), vanillin (Fig. 3) (1876), phenylacetaldehyde (Fig. 4) (1883), piperonal (Fig. 5) (1890), musk xylol (Fig. 6) (1891) and b-ionone (Fig. 8) (1893) (Frater et al., 1998).

All the above ground parts of the plant are affected. There is development of round and elongated spots surrounded by brownish red margin on the leafl ets. At later stage spots coalesce and entire leaf turns brown. On green pods, the lesions are usually circular with dark margin and pin head like dark dots representing the pycnidia in concentric circles.

It is a very important and commonly found disease of chili which observed in field as well as in storage. It is also known as anthracnose disease which is mostly seen in tropical and sub tropical regions.

Chilli or Pepper (Capsicum Sps.) originated in South America and spread into the New World tropics before subsequent introduction to Asia and Africa. Chillies are now widely grown throughout the tropics, sub-tropics and warmer temperature region of the world. The genus Capsicum is a member of the family Solanaceae.

Chilli thrips: Scirtothrips dorsalis, Thrips palmi: Thripidae

The adults of this insect are small brownish black with fringed wings. The nymphs are slender and yellowish straw coloured, later acquiring more brownish hue. They lacerate the tissues and feed on the exuding sap. Leaves become crinkled, curled upward and shed. The attack can be confused with chilli mosaic symptom.  In capsicum and chilli, they also feed beneath calyx of flowers and fruits causing flower/fruit drop and reduction in yield and market value of capsicum. Buds become brittle and drop down. Plants get stunted and bronzed. The fruits if at all formed are crinkled and small.

Chilli (Capsicum annuum L.) and bell pepper (Capsicum annuum var. grossum) are economically significant crops in India, known for their distinct attributes and culinary uses. Despite their shared progenitor, these crops exhibit varietal differences and require specific breeding strategies for hybrid seed production due to small flower size. The development of male sterile systems has revolutionized hybrid seed production, with the exploitation of Genetic Male Sterility (GMS) and Cytoplasmic Male Sterility (CMS) in chilli and bell pepper breeding. The market for chilli seeds in India is substantial, driven by the demand for high-value hybrid seeds. This chapter comprehensively reviews the botanical characteristics, genetic resources, and breeding objectives in Capsicum species, emphasizing traits like disease resistance, high yield, and stress tolerance. It also highlights varietal achievements in public and private sectors, showcasing improved cultivars and hybrids with specific attributes. The integration of molecular markers in male sterile genes facilitates efficient hybrid seed production, ensuring genetic purity and quality. Additionally, the package of practices for seed production in chilli underscores the importance of isolation, field standards, inspection, harvesting, seed processing, and quality standards to maintain seed purity and viability.

1. Anthracnose or Fruit Rot and Die Back
Diagnostic Symptoms
The disease occurs in two forms: the die back and the ripe -rot Die back symptoms
• Small, circular to irregular, brownish black scattered spots appear on leaves.
• Severely infected leaves defoliate.
• Infection of growing tips leads to necrosis of branches from tip backwards.
• Necrotic tissues appear grayish white with black dot like acervuli in the center.
• Shedding of flowers due to the infection at pedicel and tips of branches.
Fruit symptoms
• Ripe fruits are more liable for attack than the green ones.
• Small, circular, yellowish to pinkish sunken spots appear on fruits.

1. Introduction

Chilli (Capsicum annuum L.) is a major vegetable and spice crop due to its high consumption, nutritional and cash value to farmers and consumers. It is cultivated almost in whole world as consume in the form of green and red ripe fruits. China is the world leader in chilli production followed by India, Mexico, Morocco, Pakistan, Thailand, and Turkey. India is the second largest exporter in the world of dry chilli and its powder. Fruits of chilli are used as fresh salad, cooked vegetable, pickles, souces hot spices in powder form (Parey et al., 2013) and having many medicinal values (Nadkarni, 1927). Fresh green fruits of peppers and red peppers are the major source of vitamin A, C and antioxidant compounds, besides these also found minerals such as calcium, phosphorus, potassium, magnesium, iron, manganese, sodium, zinc and copper. 

Chilli (Capsicum annuum, 2n = 2x = 24, family Solanaceae) also known as hot-pepper, classified as often-cross-pollinated crop is consumed both as fresh green and dry spice type. It is a rich source of vitamin C and pungency to the consumers and world food industries. The global area and production statistics often run into different figures due to inclusion of some times only fresh green chilies, sometimes red-dry chillies and sometimes inclusion of sweet peppers also in this broad category. The global production of fresh and dry chillies in 2014 has been reported to be 32.32 million tons where China alone accounted for 16.12 million tons followed by India with over 5 million tons of production. Other major countries growing chilli are Mexico, Indonesia, Spain, Turkey, USA, Korea, Bangladesh, Pakistan, Nigeria, Thailand and Ethiopia. More than 65% of global green and dry chillies production is in Asia, while Europe contributes 12% and Africa around 10%. China is the leading producer of green and dry chillies, Area under chillies in China is less than that in India, but productivity is almost double than that in India.

Chilli or hot pepper, the Capsicum species (principally Capsicum annuum) under the family Solanaceae (Chromosome No. 2n =2x =24) is a tropical vegetable-cum spice crop commonly used throughout the world as spice for its pungency and red colour of ripe dried fruits and also for its green fruits for pungency and flavour.
Origin, domestication and adaptation in India
It is generally accepted that the Capsicum genus belonging to the family Solanaceae was originated in Bolivia which consists of 25–30 species. Five of these Capsicum species viz., C. annuum, C. baccatum, C. chinense, C. frutescens, and C. pubescens were domesticated. The largest group of varieties is found under C. annuum which is grown worldwide. Both hot pepper and sweet pepper belonging to the same species Capsicum annuum originated from the wild and weedy Capsicum annuum var. minimum distributed from the southern United States to the northern South America. The primary centre of origin of chilli is in southern and central America and secondar centre in Guatemala.

Capsicum species are members of family Solanaceae, which include tomato, potato, tobacco and petunia.  Pepper, chile, chili, aji, paprika and capsicum are used interchangeably for plants in the genus Capsicum.  The word Capsicum is reserved for taxonomic discussion (Bosland, 1992). The indigenous people of Americas evolved pepper through breeding and domestication of Capsicum species. Global diversification was facilitated by age of exploration, and subsequent establishment of land races and farmers selections.  Classical genetic and cytogenetic exploitation of Capsicum species began in 1940s and continued throughout the century (Poulos, 1994). Data on crossability and hybrid sterility are developed to reinforce or revise views on the rank of morphologically distinguishable taxa, while studies on chromosomes and isozymes aided in understanding the relationships between domesticated and wild species and the course of evolution within the domesticated species.

Chrysomelid beetle : Aulacophora foveicollis : Chrysomelidae

Adults cut tender shoots and feed on leaves resulting in holes and loss of leaf. Grubs feed on roots and underground stems leading to yellowing,wilting and drying of attacked plants.

The earliest Brassica planted in North America was Chinese cabbage, also known as celery cabbage and napa. It is becoming increasingly popular in western kitchens. When eaten fresh, the huge savoyed leaves with thick succulent midribs have a sweet flavour and crisp texture. The Pekinensis Group and the Chinensis Group are two cultivar groups of leaf vegetables frequently used in Chinese cuisine. These vegetables are turnip cultivars or subspecies that belong to the same genus as cabbage, broccoli, and cauliflower, among other Western mainstays.

Botany & taxonomy: Brassica rapa, one of two commonly cultivated mustard family (Brassicaceae) members that are variants of Chinese cabbage. Pak Choy is a type of Chinese cabbage (Brassica rapa var. chinensis). Celery cabbage is another name for Napa cabbage.

Leaf-and shoot folders: Hymenia recurvalis : Pyraustidae

Pycnarmon cribrata;Phostria piasusalis

Chironji or Charoli (Buchanania lanzan Spreng.) is an important fruit tree of agro forestry and social forestry. In the wasteland development and dryland horticulture, it assumes great significance due to its multifarious uses and capacity to withstand adverse environmental conditions. At present, it is growing under natural forest as an underexploited fruit and gives monitory reward to the tribal community of the country and seems to be boon for them. It is valuable tree species found in dry deciduous forest throughout the country excluding eastern Himalayan forests (Singh, 1982).

Chironji or Charoli (Buchanania lanzan Spreng Family: Anacardiaceae) is an excellent tree of agro forestry and social forestry. In wasteland development and Dryland horticulture, it assumes great significance due to multifarious uses and capacity to withstand adverse climatic conditions. At present, it is growing under forest condition as an under exploited fruit and gives monitory reward to tribal community of country and seems to be a boon for them. It is a valuable species found in dry deciduous forest throughout the country excluding eastern Himalayan forests (Singh, 1982). Flesh of ripe fruit is very palatable and is largely eaten raw or roasted and oily kernels are the most important part and are used in preparation of sweet meats and puddings (Singh, 1982). Mesocarp of fruit is edible and cherished by children (Munde et al, 2003). Kernel is highly nutritious and rich in protein (18.00 %) and yields sweet oil, which can be used to substitute olive and almond oil. Kernel contains 33.50 % oil, 1.90 % of which is unsaponifiable. Saponifiable part contained 20.00 % of linoleic acid. Chironji oil is non-repellant and non-toxic and is suitable for human consumption (Banerjee and Jain, 1988). Hemawathy and Prabhakar (1988) reported that total kernel lipid extracted from chironji was 65.60 % of dry kernel and consisted of 90.40 % neutral lipids, 3.4 % glycolipids and 6.2 % phospholipids. Kernel can be used for preparation of sweets. It provides quality timber wood for various uses.

Introduction

Increasing production of cereal crops, oil seed crops, and horticultural crops is becoming more important than ever before owing to increasing population and changing food habits of the people. The modern tools of biotechnology are being exploited to the fullest throughout the world for developing transgenic crop plants with improved traits. Already about 20 countries in the world are growing transgenic crops, predominately with traits such herbicide tolerance and resistance to insect-pests. However, there is a constant fear of pollen flow from theses transgenics to the neighbouring non-transgenic fields or to their weedy or wild relatives. It has become a matter of great concern to all biotechnologists to develop alternative strategies to prevent the pollen flow.

The best alternative strategy available today to circumvent the nuclear- transformation associated bottlenecks in developing tenable crop transgenics is the chloroplast transformation technology. This technology allows introduction and insertion of foreign genes into the chloroplast genome, called plastome. Chloroplasts are the site for photosynthesis in plants mostly present in leaves. In general called plastids, they are also present in other parts of the plant. For example, chromoplasts in coloured leaves and fruits, amyloplasts in starch storing organs, leucoplats in roots, and etioplasts in dark-grown seedlings. The plastids arise from proplastids - the undifferentiated form of plastids present in most plant cells. Just like nucleus, these plastids (and also mitochondria) contain their own genetic material on the chloroplast genome.

Many crops can be grown in greenhouse but the choice depends on number of factors.

1.Requirement of the farmer, what for she/he wants to grow the crop.

2.For personal use number of vegetable crops and herbs and fruits like strawberry and papaya can be grown.

3.In case of commercial crops, the market must be ascertained before the choice of the crop.

4.Greenhouse must be equipped to create micro-climate for the crop of choice.

5.The choice of crop is a crucial factor for the economic feasibility and success of a commercial greenhouse operation. The revenue of cultivated crop makes the venture to progress.

6.Crop varieties, suitable for greenhouse cultivation should differentiate themselves from open-field varieties to fetch better price on quality.

Hybridization is a potent technique to create variability for selection and breaking yield barriers, evolve varieties having built in high potential. The selection of suitable parents for hybridization is one of the most important step in hybridization program. Selection of parents on the basis of phenotypic performance alone is not a sound procedure since phenotypically superior lines may yield poor recombinations in the segregating generations. It is therefore essential that parents are chosen on the basis of their genetic value. Some of the commonly utilized techniques for assessing the genetic value of a genotype are:

Chow-Chow [Sechium edule (Jacq.) Swartz] is used in many parts of Latin America, humid tropical regions of Central America and Southern Mexico. It is cultivated in South East Asia (India, Malaysia, Indonesia and Phillipines), Central and Western Africa, Central and South America (Brazil) and other tropical regions. (Dutta 1994). In India, local cultivars are commonly grown in coastal and low-hills (1000-2000m) of Maharashtra, Karnataka, and Tamilnadu. In Tamil, it is called “Seeme Kattrikkai” (Bailey, 1947). It is an important part of dietary system of tribals of  North East Regions. It is found in kitchen gardens of every tribal. It is found in almost all states and regions but maximum variability is found in Sikkim, Mizoram and Meghalaya (Yadav et al., 2005). Its variable fruits and roots, are important elements in diet of people. Chow-Chow is widespread and is an important export crop for  Latin American countries, much still need to be learned  about this crop (Rafael Lira Saade,1996). Chow-Chow is a single seeded fruit of  Cucurbitaceous family (MacGillivray, 1953). It is a perennial rooted vine that bears edible fruits (Thompson and Kelly, 1957). In subtropical and tropical regions, it produces large edible tuberous roots. It thrives under moderate temperature in  tropical or semi-tropical environment, though it can also be successfully grown under high temperature near sea level. Chow-Chow is a herbaceous perennial creeper (Choudhury, 1967) and is a robust grower in warmer months of year and during  cold weather of July and August  plant dies back temporarily. It has a viviparous type of germination (Patnaik, 1967). S.edule is called chayote, probably from  Greek ‘Sekos’ to  fatten in a fold because it was fed to hogs ( Bailey, 1963).

The relationship between gene and chromosome was suspected at the time of rediscovery of Mendelian^, Laws. During that period Montgomery (1901) and Walter Sutton (1902) working on grasshoppers showed that chromosomes occur in distinct pairs, often of recognizable shape and size, and that synapsis involves the union of maternal and paternal chromosomes, while Winiwarter (1901) concluded from his studies in rabbit ovaries that bivalents in the first meiotic division resulted from the chromosome pairing side by side and not end to end as believed by some other workers of that time . Theodor Bovery (1902) showed from his work on polyspermy in the fertilization of sea urchin eggs that the chromosomes of an individual were not equivalent (genetic information) to one another and hence a full chromosomal complement is essential for normal development of cell. Correns (1902) and Cannon (1902) pointed out close parallelism between Mendelian segregation and chromosome reduction during meiosis and concluded that genes are located on chromosomes but they, like de Vries, supposed that maternal and paternal chromosomes move to opposite poles during meiosis. In the same year Guyer established an understanding that random assortment between different pairs of chromosomes would give the independent assortment of genes required by Mendel. Ultimately Sutton (1903) brought together the ideas from cytology and genetics to clearly show the role of chromosomes in heredity and hence to establish the field of cytogenetics. Boveri also through his work, advanced many of the same ideas and thus the hypothesis correlating genes and chromosome transmission was established, which is known as the “Sutton-Boveri Hypothesis or chromosome theory of inheritance”.

Botany :Annual Chrysanthemum is a winter annual that can be grown either as pot plants or in groups as bed plants for various ornamental purposes. There are two types of annual Chyrsanthemums: Chrysanthemum Segetum and C.coronarium. Major varieties of Chrysanthemum segetum L. are Morning Star, Evening Star, Eastern Star, Blanca, Eldorado, Gloria, Isabel, Romeo, and yellow Stone while popular cultivars of C. coronarium L. include Nivea, Oreon, Albo, Golden Crown, Luteum, Tom Thumb Golden Gem, Tom Thumb-Primrose Gem and Tetra Comet. In addition to this, there is another type of annual Chrysanthemum, i.e. C. carinatum. Popular varieties of C. carinatum S. are Merry, Atrococcineum, Burridgeanum, Eclipse, Flammenspiel, John Bright and Northern Star.

Propagation

Annual Chrysanthemums can be propagated by seeds. Their sowing time depends upon climate. It varies in different parts of India. In the Northern plains, winter season annual Chrysanthemums are sown during September–October. The seeds are sown in nursery beds, earthen pots, seed pans or wooden seed trays. The seed compost should consist of one part each of garden soil, coarse sand, farmyard manure and leaf-mould. For preparing the nursery beds, the soil should be dug up thoroughly and sufficient farmyard manure, should be mixed in soil. Raised nursery beds of convenient size (normally 60cm wide and 15cm high) should be prepared. If soil is heavy, some quantity of sand may be added. It is better if the soil of nursery bed or earthen pots is sterilized with 2% formalin. For this, soil is drenched with formalin solution and is covered with polythene sheet for 45hr. Afterwards, the polythene is removed and soil is dried before sowing the seeds.

1. Introduction

Chrysanthemum is commonly known as ‘Guldaoudi’, “Queen of the East”, “Glory of East” or “Autumn Queen”. It is one of the most beautiful and widely cultivated flowers that can be grown for its aesthetic value as well as for its commercial potential. The word chrysanthemum is derived from two Greek words, viz. “Chrysos” means gold and “Anthemon” means ‘flower’ i.e. golden flower. Chrysanthemum is the only crop that offers a great genetic diversity of flower colour, shape, forms, size, easy to propagate, growing habit, longer flowering duration and excellent vase life. Based on the shape of flower heads and floret arrangement of petals it can be used as pot plants for indoors and outdoors decoration as well as exhibition purpose; as cut flowers for flower arrangements, bouquets making and vase decoration; loose flower for making garlands, worshipping purpose and for bedding and garden decoration. Tall cultivars are suitable for background planting in borders and the dwarf and compact can be planted in front rows. 

Chrysomelid beetle : Aulacophora foveicollis : ChrysomelidaeAphids : Macrosiphoniella  sanborni; Myzus  persicae; Brachicaudus  helichrysi; Aphis  gossypi; Aphis fabae; Aulocorthum circumflexum: Aphid

Chrysanthemum   is infested by different species of aphids. Aphids are small, soft bodied insects and their colour varies with species. Both nymphs and adults cluster on the growing stem tips and under surface of leaves. As a result, the plants show loss of vigor, distortion of leaves and flowers, yellowing, premature leaf fall and stunted growth. The damaged plants bear only undersized buds and they remain unopened. Peak damage period is November-December. Secretion of honeydew by the aphids favor development of sooty mould which hinders photosynthesis and the plants become stunted. They are also vectors of virus diseases.

Cinnamon butterfly: Chilasa clytia clytia : Papilionidae

Larvae defoliate plants. The larvae are pests on many crop plants and weeds and are common in the plains. The larvae are jet black at hatching. They develop a series of broad white patches. The adult is a common butterfly rich velvety brown, and spotted with white dots. The hind wings have arrow shaped streaks and crescent shaped spots.

1. Gummosis.
Diagnosic Symptoms
• First symptoms are dark staining of bark which progresses into the wood.
• Bark at the base is destroyed resulting in girdling and finally death of the tree.
• Bark in such parts dries, shrinks and cracks and shreds in lengthwise vertical strips.
• Later profuse exudation of gum from the bark of the trunk (characteristic symptom).
• The infection spreads both upward to the leaves and even fruits and downward to the roots causing fibrous root rot.
• The fibrous root rot destroys a major portion of the root system.
• However, the trunck and root infections may usually result in ultimate drying of the tree (Fig-1).
Etiology
Scientific Classification
Kingdom : Fungi
Division : Eumycota

Cultivation of citrus holds promise in arid irrigated tracts. The major citrus fruits under cultivation in arid regions are acid lime , lemon, Kinnow, Mandarin hybrid, sweet orange and grapefruit .Acid lime and kinnow are widely grown. Citrus fruit are grown  through out country for its  nutritive and medicinal value (Chadha, 2001) . Citrus is world’s leading fruit crop. In India, it is cultivated in the states of Maharashtra, A.P., Punjab, Rajasthan, H.P., U.P., M.P., Karnataka, T.N., J&K., Odisha, Gujarat, Assam, & Sikkim, For obtaining quality plant material, propagation is an important aspect. Citrus is largely propagated   by budding except kagzi lime which is raised from seeds because of occurrence of polyembryony and sweet lime which is  commercially  propagated by stem cuttings. Kagzi lime and lemon can also be propagated by layering. In case of citrus the availability of proper plant material is very much essential.

The research work carried out throughout citrus growing countries of the world including India showed utility of different rootstocks for citrus plants, which varies greatly with scion variety and agro-climatic condition. A wide range of citrus rootstocks are available, each having desirable attributes. The success of a rootstock is determined by its tolerance to prevailing conditions of soil, climate and diseases. Citrus plants are unusual in that many species and cultivars including the commercial rootstocks reproduce true to type from seed. Commercial citrus rootstocks are usually highly polyembryonic but there can be 1-40 zygotic seedlings in the seedbed.

Citrus butterfly: Papilio demoleus, P. polytes : Papilionidae

The pest is distributed all over the world and has a host range that includes citrus and other rutaceae plants like Aegle marmelos. Adult has the head and thorax black with a creamy-yellow coloration on the underside of the abdomen. Wings are dull black, orna-mented with yellow markings and a distinct red patch on the hind wing. The underside is orange and yellow coloured and can be seen when it flirts for honey collection or just before egg laying. The Antenna is black and clubbed.

Origin and history: Citrus is the leading fruit crop in the world. In India, citrus ranks second in area sharing 12.8% of the total area under fruit crops with 9.6% share in production. Under citrus group, mandarins are the most important, occupying 50% of the total area under citrus followed by sweet orange and limes. Citrus fruits are grown mainly in Maharashtra, Andhra Pradesh, Punjab, Karnataka and North-Eastern region. 

1.    Nagpur mandarin was introduced in India in 1894 by Shriji Raja Bhosle. 

2.    Kinnow can be grown in high density planting by using the cultivar  Troyer Citrange'  as a root stock by spacing the plants at 1.8 x 1.8 m2. 

3.    Classification of citrus was given by Tanaka and Swingle. 

4.    Grape fruit is also known as Forbidden fruit, Breakfast food.

Citrus crop includes lime, lemon, sweet orange, mandarin orange, Kamala orange, grapefruit, malta and pomelo etc. The disease which attacks one species of citrus mostly attacks other species also.

3.1 Introduction

Genetics deals with genes and cytogenetics with chromosomes that harbour genes. On the other hand, plant breeding strives to upgrade the genotypes of crop plants. So, the plant breeding methods should be based on genetic principles. Dear students, you should have clear understanding of genetics in broad sense so that you can appreciate the applicability of breeding methods. As I have already pointed out that you have been taught the course ‘Principles of Genetics and Cytogenetics’ in the first semester, only a brief discussion is followed for your review and better understanding.

3.2 Character

When we call ‘character’ or ‘trait’ in genetics, we mean any morphological, anatomical, biochemical or behavioural feature of an organism. For instance, flower colour, blooming period, leaf size, size of guard cells in stomata, vitamin C content, disease resistance etc. A single gene or a number of genes may govern the development of a character and, often it is influenced by the environment. Characters may be qualitative or quantitative.

Classification of fruits: Classification is the system of grouping or placing of an individual according to nomenclature. It is very useful to the pomologist, it helps to:

•    To identify and naming the crop.

•    To study the close relationship.

•    To know their hybrids and crossing behavior.

•    To know their compatibility & inter grafting ability.

•    To know their adoptability to soil & climate.

Pomology: Pomology is a branch of horticulture which deals the cultivation utilization and management of the fruit crops. eg. Mango, Banana, Citrus, Papaya, Guava etc. The term pomology is a combination of two words “Poma” in Greek means Fruits later subsequently transfer in to “Pome” in Latin word means Fruits and Logos means Study.

I. Classification of fruit crops

1. Based on botanical relationship