eChapters

1. Introduction

Eggplant or brinjal (Solanum melongena L. family. Solanaceae) is the major vegetable crop of wet and hot climatic zone of south Asia (Srinivasan and Huang, 2008). After China, India is the second largest brinjal producer country in the world (Majumdar and Das, 2020). It is nutritious vegetable and consumed in throughout the world. Brinjal is considered as Indian native crop and it has been cultivated for last 4000 year. India is known to be the Origin Centre of brinjal cultivation, from where it distributed to throughout the world (Choudhury and Malda, 1968). In India, brijnal crop grow almost throughout the year. Brinjal fruit contains moisture 92.7g, carbohydrates 4.0g, proteins 1.4g, minerals 0.3g, vitamins 124 I.U. and vitamin 12.0mg per 100 g of edible part (Kalra et al., 1988). It is used as vegetable purpose as well as pickle (Singh et al., 1963).

Introduction

Broccoli (Brassica oleracea L) belonging to family Brassicaceae, is an herbaceous annual or biennial plant which is cultivated for its edible flower heads being are used as vegetable or salads. The broccoli plant has a broad green stalk, or stem, that give produces thick, leathery, oblong gray-blue to green in color leaves. The plant produces large branching green flower heads covered with numerous white or yellow flowers. Broccoli can be annual or biennial depending on the variety. Broccoli is a rich source of vitamins, minerals and antioxidants and has a reputation as super foods (Hatanaka and Ware, 2020).

It is admitted that they are susceptible to a numerous of serious diseases that leads to reduction in yield. Thus, it is the utmost requirement to control such biotic stressors in order to obtain desired quality and decent yields. The most important diseases and its control measures are being portrayed in this chapter for both home gardener and the commercial producers for cruciferous vegetables particularly broccoli (Mani et al., 2020).

Blackrot of Cabbage

Economic Importance

Blackrot is an important bacterial disease of cabbage and other crucifer crops worldwide. The disease was first described in New York on turnips in 1893, and has been a common problem for growers for over 100 years (Smart and Lang, 2013). Blackrot has been given many names such as bacterial blight,black stem, black vein, stem rot or stump rot (Pfeufer and Davis, 2019). These pathogen is particularly damaging to cabbage and cauliflower, but turnip, rutabaga, collard, kohlrabi and Chinese cabbage are also susceptible. Broccoli and radish aregenerally resistant to Blackrot (Flynn,1999).

Chilli is reported to be an inhabitant of South America and widely scattered in all tropical and sub-tropical countries including India. Amongst all the important consumed crops, chilli occupies a dominant position and its economic losses worldwide due to few serious diseases like chilli anthracnose, Phytophthora leaf blight and fruit rot, bacterial leaf spot, bacterial wilt, Cercospora leaf spot, chilli leaf curl virus and so on. Capsicum annuum L., C. frutescens L. are the biological names of chilli. Bird’s eye chilli is grown in Mizoram and some areas of Manipur and Assam. Chilli has got its own regional names. In Hindi, it is popularly known as Lal Mirch, in Gujrat as March, in Marathi as Mirchi and so on. Kanthari White is grown in Kerala and some parts of Tamil Nadu. Kashmir chilli is grown in temperate region such as Himachal Pradesh, Jammu and Kashmir and also in sub-tropical regions of North India. Red chilli held high amount of vitamin C and provitamin A, whereas green chilli too contain a considerable amount of both substances. In addition, peppers are a good quality source of most B vitamins, vitamin B6 in particular. They are very high in Potassium, Magnesium and Iron supplement.

Introduction

Chili peppers, also spelled chile or chilli, are varieties of the berry-fruit of plants from the genus Capsicum, which are members of the nightshade family Solanaceae, cultivated for their pungency. Chili peppers are widely used in many cuisines as a spice to add "heat" to dishes.

Botanical Name : Capsicum annum

Family : Solanaceae

Chromosome Number (2n) : 24

Diseases of Chilli

 1. Powdery Mildew

The disease was first reported from Morocco in 1937.

Anthracnose or Fruit Rot and Die Back

Colletotrichum capsici

Diagnostic Symptoms

Dieback symptoms

• Small, circular to irregular, brownish black scattered spots appear on leaves .

Introduction

Chrysanthemum, commonly known as “mums” or “chrysanths,” is a genus of plants that bloom and belong to the Asteraceae family. These plants are native to Asia and northeastern Europe, with China being the primary centre of diversity for the genus. Chrysanthemums are well-known for their attractive and colorful f lowers, and they are popular ornamental plants in gardens, floral arrangements, and as cut flowers.

Chrysanthemum morifolium is a herbaceous perennial flowering crop. It is the second most popular cut flower worldwide, right behind roses, and a significant decorative plant for commerce (Silva et. al., 2013). Certain species’ flowers, such as those of Chrysanthemum morifolium and Chrysanthemum indicum, are rich in nutrients and biologically active substances and are used to make medicinal tea and cosmetics, respectively (Lin et. al., 2010).

Gummosis

Phytophthora spp

Diagnostic Symptoms

• Dark water soaked large patches appear on the basal portions of the stem near the ground level.

Introduction

The innermost layer of the pericarp is the endocarp. The segments are also called “liths”, and the space inside each lith is a locule filled with juice vesicles, or “pulp”. From the endocarp, stringlike “hairs” extend into the locules, which provide nourishment to the fruit as it develops. Citrus fruits are notable for their fragrance, partly due to flavonoids and limonoids (which in turn are terpenes) contained in the rind, and most are juice-laden. The juice contains a high quantity of citric acid giving them their characteristic sharp flavour. The genus is commercially important as many species are cultivated for their fruit which is eaten fresh, pressed for juiceor preserved in marmalades and pickles.

Coconut

 Kingdom: Plantae

 Phylum: Magnoliophyta

 Class: Liliopsida

 Subclass: Arecidae

 Order: Arecales

 Family: Arecaceae

 Genus: Cocos

 Species: Cocos nucifera Linnaeus

 1. Bud Rot

The fungus Phytophthora palmivora is responsible for the ailment known as “bud rot.” Butler first mentioned bud rot in India in 1906. Due to a number of factors, the disease has recently spread to practically every region of the state in a very serious manner.

Cauliflower, Cabbage and Knol khol
1. Leaf spot
Pathogen
Alternaria brassicae (Berk.) Sacc.
Symptoms
Alternaria leaf spot usually appear in early stage in cauliflower while at later stage symptoms in cabbage appear as circular light brown spot in leaves. Concentric rings are clearly visible on the spots. In older plants on leaves, petioles and stem, brown to black circular to slightly elongated spots appear.

Stem gall

Diagnostic Symptoms

• Symptom appears in the form of tumor-like swellings of leaf veins, leaf stalks, peduncles, stems as well as fruits.

• Infected veins show a swollen hanging appearance to the leaves.

Wilt

Fusarium oxysporum f.sp. vasinfectum

Diagnostic Symptoms

• Disease affects the crop at all stages.

Introduction

Cowpea (Vigna unguiculata subsp unguiculata) is widely grown in Africa, Asia and Brazil. The crop is grown on about 7 million ha in warm to hot regions of the world (Rachie, 1985). It acts as a major source of protein (20-30%) for Indian vegetarians. Besides, it contains high carbohydrate. Cowpea is generally rich in lysine and limiting in sulphur amino acids and important for human food and animal feed. The crop is also valuable source of dietary fibre as well as vitamins and minerals including folate, thiamin and riboflavin. Besides this, it can fix about 240 kg ha^-1of atmospheric nitrogen and make available about 6070 kg ha^-1nitrogen for succeeding crops grown in rotation with it (Aikins and Afuakwa, 2008).

The crop is prone to several diseases induced by species of pathogens belonging to various pathogenic groups viz., fungi, bacteria, viruses, nematodes, and parasitic flowering plants, and it constitute one of the most important constraints to the profitable Cowpea production in all agroecological zones. Different diseases like anthracnose, fusarium wilt, bacterial blight, Cowpea mosaic virus (and several other less prominent viruses), cercospora leaf spot, rust and powdery mildew etc are reported to be important disease of the crop. In this chapter detail of these diseases and their integrated management approaches are mentioned.

Introduction

Members of the family Brassicaceae, sometimes known as Cruciferae, include cruciferous vegetables, such as cauliflower, cabbage, kale, garden cress, bok choy, broccoli, brussels sprouts, mustard plant, and other related green leafy vegetables. This family comprises several genera, species, and cultivars that are cultivated for food production. While some are shrubs, herbaceous plants make up the great bulk. The leaves are simple (though sometimes deeply incised), without stipules, and grouped in rosettes or alternately on stems. The terminal inflorescences are devoid of bracts. Four longer free stamens and two shorter free stamens are present on. blossoms, as well as four free petals and sepals that alternate.

1. Damping off
Pathogen
Pythium spp
Phytophthora spp
Fusarium spp
Sclerotium spp
Symptoms
It is a term used to describe the damage caused by various fungi to the seed and emerging seedling in the reduced plant stand and sometimes it is so serious that  resowing becomes inevitable. Major symptoms are the failure of the seedlings decay or sudden death of the emerged seedlings roots and lower stems of emerged seedlings become soft and watery and may be reddish brown in colour.

Cucurbits are major crops of countries having a wide variety of vegetables. Cucurbits include bottle gourd, bitter gourd, pumpkins, squashes, ridge gourd, sponge gourd, and cucumbers. Cucurbits are a large, diverse crop group that are susceptible to over 200 diseases (Zitter et al., 1996). A wide range of pathogens affect the productivity of cucurbits. The diseases may be caused by fungi, bacteria, Cucurbits crops are warm-season large group of crops that are cultivated and harvested over different seasons like spring, summer, and winter. These crops as a group are an important part of a diverse and nutritious diet. Melons are eaten as fruits, whereas summer and winter squashes, cucumber, and pumpkin are eaten as vegetables. In addition, cucurbits are used for fiber, utensils, decoration, ceremonial and medicinal purposes.

A wide range of pathogens affect the productivity of cucurbits, which constitute over 200 diseases (Zitter et al., 1996). The diseases may be caused by fungi, bacteria, viruses, or mycoplasma- like organisms. The disease may be soilborne, seedborne (carried by seed), spread by wind, or transmitted by insect vectors. The moisture content of the seed, storage period, prevailing temperature, and degree of invasion influence the development of seedborne fungi (Anjorin and Mohammed 2009). The pathogen may cause seed abortion and rot, necrosis, reduction, or elimination of germination capacity as well as seedling damage at later stages of plant growth, resulting in the develop- ment of the disease as systemic or local infection (Khanzada et al., 2001). The diseases cause heavy loss in terms of yield and quality. The diseases caused by pathogen are controlled by fungicides against fungal diseases, antibiotics for bacterial diseases, or insecticide in case of viruses transmitted by insect vectors. The diseases of cucurbetaceous crops can be managed by adopting different cultural, biological, and chemical methods of disease management. The following management practices are required to be taken into consideration for raising disease-free cucurbitaceous crops:

Introduction

Cucurbits, a versatile and economically significant group of plants within the Cucurbitaceae family, encompass a wide array of popular vegetables such as cucumbers, pumpkins, squash, zucchinis, and melons. These cucurbit crops are not only vital components of global diets but also key players in agriculture. Also, cucurbits are used as fibre source and for utensil preparations, decorations, and ceremonial and medicinal purposes (McGrath 2004). However, their productivity and quality are frequently compromised by a range of diseases. In this chapter, we embark on a comprehensive exploration of the diseases that afflict cucurbits, including their names, symptoms, causative agents, etiology, disease cycles, favourable conditions, and strategies for effective management.

Downy mildew

Pseudoperonospora cubensis

Diagnostic Symptoms

• Yellow, angular spots restricted by veins resembling mosaic mottling appear on upper surface of leaves .

Introduction

Elephant foot yam (Amorphophallus paeoniifolius (Dennst.) Nicolson) is an important edible tropical tuber crop since time immemorial in the tropics and sub-tropics (Behera et al., 2009) and regarded as “King of tuber crops” due to its higher biological efficiency as a food producer ). It belongs to the family Araceae. Tender stem and leaves of this tuber crop are used for vegetable purpose. The corms are rich in nutrition and contain 18.0% starch, 1-5% protein and up to 2% fat. Leaves contain 2-3% protein, 3% carbohydrates and 4-7 % crude fibre. It has great scope for commercial exploitation as a medicinal crop in pharmacological industry and widely recommended as a remedy in all three of the major Indian medicinal systems: Ayurveda, Siddha and Unani. The corm is prescribed for bronchitis, asthma, abdominal pain, emesis, dysentery, enlargement of spleen, piles, elephantiasis, diseases due to vitiated blood, and rheumatic swellings. Pharmacological studies have shown a variety of effects, specifically antiprotease activity, analgesic activity, and cytotoxic activity. It has also been found to be a potential inhibitor of bacteria activity when used with antibiotics. In addition, Amorphophallus corm is a good sources of phyto- aestrogens and are effective alternate or complementary to conventional hormone replacement therapy for symptoms associated with menopause and chronic degenerative diseases in women. It is a crop of South-east Asian origin, and grown widely in Philippines, Malaysia, Indonesia and South eastern Asian countries. In India, the crop is popular in the state of West Bengal, Andhra Pradesh, Kerala, Uttar Pradesh, Bihar, Madhya Pradesh, Maharashtra, Orissa, Tamil Nadu and Karnataka. West Bengal is the highest producer of elephant foot yam (293.84 thousand MT in the year 2015-16) followed by Andhra Pradesh (207.52 thousand MT) and Kerala (110.37 thousand MT) (Source: National Horticultural Board). However, the crop is gaining popularity dueto its shade tolerance, easiness in cultivation, high productivity, less incidence of pests and diseases, steady demand and reasonably good price.