Ebooks

Plant pathology is an important branch of Agriculture due to the losses caused by the plant diseases. Plant diseases are one of the important constraints of crop production causing tremendous losses to crop yields to the tune of millions of money besides causing death to thousands of people died due to hunger worldwide. Considering its importance plant pathology is being taught as a compulsory subject to the students of Agriculture. Through this book attempts have been made to provide most recent information about the diseases of horticultural crops to the students of Agriculture doing under-graduate courses as per the 5th Deans committee recommendations.

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.

Mango (Mangifera indica) is a tropical fruit tree that is well-known and cherished for its delicious, sweet, and juicy fruit. It is one of the most widely grown and economically important fruit crops in the world, primarily cultivated in tropical and subtropical regions. Mangoes are not only enjoyed for their taste but also for their nutritional value, as they are rich in vitamins, minerals, and antioxidants. However, like all agricultural crops, mangoes are susceptible to a range of diseases that can impact their growth, yield, and fruit quality. These diseases can be caused by various pathogens, including fungi, bacteria, viruses, and nematodes. 1. Powdery mildew (caused by Oidium mangiferae) is a fungal disease that affects mango trees, leading to significant losses in fruit production if left unmanaged.

Introduction The banana (Musa parasidiaca) belongs to the Monocotyledons class, the Zingiberales order, and the Musaceae family. It is indigenous to Southeast Asia. They thrive in tropical and subtropical climates and are widely grown in countries such as India, China, the Philippines, Ecuador, Brazil, Uganda, Colombia, and Indonesia. A banana’s average length is 7 to 9 inches, and its diameter is 2 to 3 inches. Bananas are frequently planted during the rainy or monsoon season, when the soil is moist and the young plants can absorb enough water. In tropical and subtropical climates where they are commonly grown, the planting season typically runs from April to June. Planting may take place in September or October in areas with a dry season, following the rainy season.

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.

Introduction Carica papaya is a tree-like herb that grows 2 to 10 meters tall and is often unbranched, cylindrical & hollow stem Fruits are large, cylindrical, with fleshy orange pulp. Numerous, small, black, round seed with gelatinous aril. Papaya leaves have historically been used to treat thrombocytopenia brought on by a dengue infection. (Chinnappan et. al. 2016; Sharma et. al. 2019). Papaya fruits have healing capabilities against cancer, antimicrobial anti-malarial, anti-tumor, anti-inflammatory, antioxidant, immune-boosting, blood sugar-lowering, wound healing, gastro-protective, and capable of curing fever, asthma, jaundice, irregular menstruation, and beriberi. The pharmaceutical and wellness industries have seen a steady rise in demand for papaya as a result of researchers’ recent discovery of their therapeutic potential.

Introduction The Myrtaceae family includes the guava (Psidium guajava L.), a significant fruit crop in India (Nakasone and Paull, 1998). It was originated from Mexico or Central America and later spread to Asia, Africa and Europe. Some of the guava cultivars, which are used to produce seeds-free fruits, are triploid (2n=3x=33) while some are diploid (2n=22). It is primarily grown in tropical and subtropical nations including India, China, Thailand, Pakistan, Bangladesh, Mexico, Indonesia, and Thailand. The nutritionally rich, vitamin and mineral-rich guava is referred to as the “poor man’s apple”.

Grapevine One of the fruits that is grown worldwide most commonly, grapes are said to have a longer history of human interaction than either rice or wheat. Apart from their nutritional significance, grapes are today regarded as one of the most lucrative crops. The grapes are farmed for a variety of uses, including the manufacture of raisins, wine, juice, canning, and table grapes. More grapes are produced worldwide than any other fruit crop. Approximately 11 million hectares are devoted to growing grapes, which yield 75 million tonnes yearly. More than half of the world’s supply of grapes was produced in Spain, Italy, and France. Grapes are cultivated in India in both tropical and subtropical climates. In Maharashtra, Karnataka, Andhra Pradesh, and Tamil Nadu, commercial grape production only started in the last 40 years. Grapevine production affect many sever diseases like downy mildew, powdery mildew, Anthracnose, Black rot, Rust, Bacterial canker and abiotic causes.

Introduction Pomegranates are a tasty, juicy, sweet fruit that are rich in nutrients. Punica granatum is its scientific name, and Iran is where it was originally found. Because pomegranates may be cultivated effectively in regions of the nation with dry climates, they hold a distinctive place among the fruits that are grown there. Other names for pomegranates include Dadim in Sanskrit, Bedana in Bengali, Anar in Hindi, and Madulai in Tamil. The states of Maharashtra, Gujarat, Rajasthan, Karnataka, Andhra Pradesh, Tamil Nadu, and Uttar Pradesh are the primary locations for its cultivation. From the perspective of export, this fruit is also highly significant. Pomegranate is referred to as a “Super Food” because of its many health and nutritional advantages. It is one of the greatest sources of antioxidants and has significant medicinal and nutritional value. Ripe fruit has a pleasant and nutritious juice. Juice from pomegranates in the summer, sherbet is incredibly refreshing. Pomegranates are regarded as a medication for long life and excellent health in the Ayurvedic medical system.

Introduction The apple (Malus domestica), a valuable and economically significant crop, is grown in India’s northwestern Himalayan region. After Orange, Banana, and Grape, it is the fourth most widely grown fruit worldwide. The tree is native to Central Asia, where its wild ancestor Malus sieversii is still found today. Apples have been cultivated in Asia and Europe for thousands of years. The world’s largest apple grower is China and in India it is grown in the hills of Uttarakhand, Himachal Pradesh, and Jammu & Kashmir in India. The average summer temperature during the active period is about 21-24°C growing season. Apple does this best in areas where trees are dormant. The color development will be better in winter when plenty of sunlight hits. It is possible even at an altitude of 1500 -2700 meters from sea level. 1000-1250 mm well distributed rainfall during the growing season which is most suitable for optimal growth and fertility of apple trees.

Introduction Brinjal (Solanum melongena), is a self-pollinated plant also known as eggplant, is an easily cultivated plant belonging to the Solanaceae family.Brinjal ishigh productive vegetable and easily grown everywhere.It is also known as poor’s man vegetable. Brinjal is cultivated widelyand grown as a vegetable crop in any environment. Brinjal grown large amount in India, Pakistan, Chinaand United States. The origin of the brinjal is India. In Brinjaleconomic parts are fruit. It is a high nutritional valuable food.The brinjal fruit and whole plant use as a medicine in some area. It is cultivated everypart of India except high attitude, all the year around. Depending upon consumer’s preference and yield, different types of cultivars are cultivated.Somewild spp of brinjal are fond in northeast states of India and Malaysia. Solanum insanum, a wild cultivar of the plant, mainlyobserved in the dry and hilly region of west Bengal.Some yellow color brinjal varieties are found in Malaya.

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.

Introduction Okra (Abelmoschus esculentus (L).is a cross pollinated vegetable crop. Okra originated near about Ethiopia& its cultivation became widespread in North Africa and the Middle East (Lamont, 1999; Tindal, 1983). Okra is grown commercially in many nations, such as Ethiopia, Cyprus, India, Bangladesh, Afghanistan, Pakistan, Turkey, Iran, Western Africa, Yugoslavia, Myanmar, Japan, Malaysia, Thailand, Brazil, Southern United States, and Ethiopia (Purseglove, 1987; benjawan et al. 2007; Qhureshi, 2007). It is a widely used, high-valued vegetable crop that is commercially grown for its tender pods during the spring, summer, and kharif seasons. Okra has high moisture content, making it a good source of vitamins, minerals, and mucilage. Okra is cultivated and consumed commercially throughout the year in many different places of India. 

Introduction Potato (Solanum tuberosum) is a widely cultivated and essential staple crop globally, known for its versatile culinary applications and nutritional value. With the exception of Kerala, potatoes are grown in practically every state in India under a variety of climatic circumstances. During the brief winter months, which span from October to March, 82% of potatoes are grown in plains. In West Bengal, potatoes are the most widely grown crop after grains (Chakraborty, 2012). Originating from the Andes region of South America, potatoes have become a crucial part of diets worldwide, providing carbohydrates, vitamins, and minerals. With a rich history dating back to ancient civilizations, including the Irish potato famine, this crop has played a significant role in shaping agricultural practices and food security.

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.

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.

Introduction Tomato scientifically known as Solanum lycopersicum L. is a widely cultivated and consumed fruit that is often mistaken for a vegetable due to its culinary uses. Belonging to the Solanaceae family, tomatoes are native to western South America with their domestication dating back to ancient civilizations in Mesoamerica. Tomatoes are prized for their vibrant red colour, juicy flesh, and rich, slightly sweet f lavour. They are a versatile ingredient used in a wide range of culinary dishes, from salads and sauces to soups and sandwiches. Tomatoes are a significant source of essential nutrients, including vitamin C, vitamin K, potassium, and folate. Additionally, they contain the antioxidant lycopene, which is believed to have various health benefits.

Bulbous herb (Onion) that belongs to Alliaceae family and usually called as the “Queen of the Kitchen.” It is an important biennial vegetable crop grown in India with high export value. A crop that thrives in temperate climates where temperatures between 12.8 to 23°C are necessary for vegetative growth and 20 to 25? are required later for proper bulb development. Onion pungency is due to the presence of allyl-propyl-disulphide. The pigment quercetin and anthocyanin is responsible for yellow and red colour of onion. It has medical benefits like lowering disease risk of cardiovascular disease, diabetes and atherosclerosis. It possess antimicrobial, anti-inflammatory and antioxidant properties (Wilson and Demmig-Adams., 2007).The bulb is useful as diuretic and heart stimulant (Ahmad et al., 2016).

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.  

Introduction The betel vine, scientifically identified as Piper betle L., belongs to the Piperaceae family, which encompasses plants such as pepper and kava. Paan leaves, widely cultivated in countries like Thailand, Philippines, India, Malaysia, Taiwan, Sri Lanka, and various Southeast Asian nations, are commonly used as a popular mouth freshener after meals. This traditional practice is predominantly observed in South Asia and among specific Asian diaspora communities worldwide, where betel leaves are commonly chewed as part of a betel quid or paan, often combined with areca nut or tobacco. In the cultural traditions of Odisha, offering a bundle of betel leaves symbolizes respect and marks the beginning of auspicious events. Taxonomically, betelvine falls under the genus Piper in the Division Magnoliophyta, Class Magnoliopsida, Order Piperales, and Family Piperaceae.

Introduction Mulberry is a very hardy and fast growing perennial plant belonging to the genus Morus of the family Moraceae. The leaf of mulberry is used for feeding and rearing of the silkworm, for the production of silk yarn. It is estimated that mulberry silk worm (Bombyx mori) contributes around 90 % of the total global raw silk production and it is a very attractive economic activities mostly to the rural people. In addition to the utilization of mulberry leaves as silkworm feed, it is being used for many other purposes due to its high nutritive value and delicious taste is getting importance as valuable food stuff as well as environmental importance of mulberry taking into account several aspects of its role as animal feed, foodstuff, phyto medicine and remediation of polluted soils and atmosphere etc.

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).

Introduction Roses, widely cultivated as cut flowers in greenhouses, as entire plants in nurseries, or within home gardens, encounter common issues across these diverse growing environments, including black spot, Botrytis blight, downy mildew, powdery mildew, and rust. Specific challenges like downy mildew and rose rosette gained prominence in the 2010s. The susceptibility of roses to various diseases varies by geographical region; for instance, rose replant disease is a concern in Europe but not in North America. Greenhouses and tropical climates, as seen in Central and South America, face heightened issues with powdery mildew, downy mildew, rust, and Botrytis blight. Disease management proves costly and can constrain rose production, prompting innovations like the adoption of hydroponics in Colombia, leading to improved pest control, enhanced rose quality, and increased productivity.

A  Afflicted tissue  247  Agricultural waste  232, 242  Agronomic practices  11  Agro-processing  13  Anamorph  120, 230  Antibiotics  98, 246, 249, 293  Antioxidants  8, 17, 69, 100  Atmosphere  176, 288  B  Biotic factor  161  Blisters  43, 64, 234, 247, 265  Blossoms  45, 76, 101, 226, 309, 316, 330  Bordeaux mixture  20, 21, 31, 61, 74, 84, 88, 95, 97, 110, 144, 147, 275, 293, 299, 300, 303  Botanical  27, 129, 141, 153, 171, 183, 195, 237, 238, 291, 309