eChapters

The vegetables and fruits are largely consumed fresh and day by day, their market demand is increasing due to nutritious quality. However, market supply is not sufficient to meet public demand throughout the year as production is inadequate because crop production has not increased substantially in recent years due to climatic changes. Another important reason for low production is the economic losses incurred due to damages of insect pests and plant diseases.

Since ancient times, reduction in pest and disease incidence is sought by spraying of pesticides including conventional preparations such as tobacco decoction, Bordeaux mixture, neem leaf extract etc. During the green revolution years, the synthetic pesticides were greatly recommended for pest and disease control and thereby increasing crop yields many-fold. Having experienced the spectacular improvement in both yield and quality of marketable produce, farmers were solely dependent on synthetics and ultimately abandoned other control measures.

Protected cultivation structures such as greenhouses, polyhouses, and net houses represent significant advancements in agricultural production, offering growers the ability to create an environment that is partially or fully isolated from external weather conditions. These structures are vital tools in modern horticulture and floriculture, especially in areas experiencing unpredictable weather patterns, water scarcity, and heightened pest pressures. The core objective of protected cultivation is to optimize the internal microclimate to meet plants’ physiological needs, ensuring higher yields, improved quality, and year-round cultivation. Achieving these outcomes requires a deep understanding and management of various microclimate factors, such as temperature, relative humidity, light intensity and quality, carbon dioxide (CO?) concentration, and air circulation. Each of these elements plays a crucial role in influencing plant health, photosynthetic efficiency, nutrient uptake, resistance to pests and diseases, and overall productivity.
Effective management of the microclimate begins with controlling temperature, which is arguably the most important factor affecting plant growth. While optimal temperature ranges vary by crop, even small deviations can disrupt essential physiological processes like germination, transpiration, and flowering. To maintain ideal temperatures in protected environments, growers employ a combination of passive and active strategies, such as utilizing roof and side vents for natural ventilation, applying shade nets during periods of intense sunlight, using fogging systems for evaporative cooling, and installing heaters or thermal blankets during colder months. These tools are often automated with sensors and climate controllers, making the system responsive and energy-efficient. In addition to temperature, managing relative humidity (RH) is essential.
Excessive RH can encourage the growth of fungal pathogens, while low RH can lead to water stress and hinder pollination. Maintaining RH between 50% and 70% is ideal for most vegetable and ornamental crops. This can be accomplished

Introduction

Cucumber is one of the most popular vegetable of cucurbitacae family and grown worldwide for its freshly harvested fruits. Fruit yield in cucumber is suppressed due to its fruiting habit. Fruits developing from the first pollinated flower inhibit the development of subsequent fruits. This phenomenon is broadly known as crown fruit dominance or first fruit inhibition. Therefore, in mechanical once over harvest of seeded cucumber, only one to two fruits per plant are developed. Fruit set inhibition is less in seedless cucumber when compared to its seeded counter part. Parthenocarpy is the development of fruit without fertilization. This phenomenon was first studied in cucumber byNoll (1902) who introduced the term parthenocarpy. In parthenocarpic lines, a larger proportion of photosynthates could be diverted to fruit tissue instead of producing seeds. Partheonocarpic habit has become indispensable to greenhouse cucumber production because it alleviates the need for bees. Individual plants in the greenhouse produce many fruits simultaneously, with many fold higher yield in comparison to field grown crop.

Greenhouse or parthenocarpic cucumber production is very popular in many areas of the world. The fruits of parthenocarpic cucumber are mild in flavour, seedless and have thin edible skin that requires no peeling. Fruits are generally 10-14 inches in length and 200 g in weight. The parthenocarpic varieties require no pollination for fruit setting. If pollination occurs, the fruit will form seeds, shape of fruit will be destroyed and develop bitter taste. It is therefore essential to prevent bees and other pollinators entering the green houses. Cucumber cultivars are selected for commercial use based on quality and yield characteristics. An important quality factor is the shape of the cucumber referred to as the length to diameter (L/D) ratio. This becomes important to meet specifications of the number of whole cucumber units per container. The cool marine environment causes the L/D ratio of many cultivars to be undesirably long and therefore many of the useful cultivars for other production regions have been eliminate. The presently available parthenocarpic cucumber cultivars have been bred and developed in Europe under similar climatic conditions and produce fruit with desirable L/D ratios. The parthenocarpic cultivars have potential for improvement of both the L/D ratios and fruit interior quality.

In India, the total losses of vegetables due to inadequate post-harvest handling, transportation and storage facilities have been estimated at least 25-40%. However, in some vegetables, the post-harvest losses may be as high as 80-100%. Being highly perishable nature of the vegetables, the losses always increase as the produce moves from harvesting to the consumer. Vegetables with a loss of as little as 5% in fresh weight show shrivelled, wilted and staled appearance, which makes the vegetable tissues tough, non-crispy and unpalatable, and eventually, lowers their saleability and consumer acceptability considerably.

Improper harvesting, handling, transportation, storage and distribution of vegetables result in significant post-harvest losses. In such situations, the reduction in post-harvest losses of perishables becomes more essential in countries like India. If these losses are minimised by handling and storing the produce carefully, the following gains can be realised:

The management of storage in open and closed storage is critical before start of any seed processing activities. When seed lots reach the shop floor, they need to be stored properly. Unlike commercial produce seed lots cannot be stored in bulk. These need to be stacked lot wise and there is problem of “stackburn”-resulting from successive layers in building a bag stack. In crops like soyabean-”stackburn” can have detrimental effect on seed quality. The quality parameters like germination and viability can get lost instantly if not properly stacked on the pallets.

Acid soils occupy a considerable area in the country. There are about 90 million ha. of acid soils (27.4 per cent of total geographical area) spread across several states. They are found to occur in the Himalayan region, the eastern and north-eastern plains, peninsular India and the coastal plains under varying environmental conditions of landscape, geology, climate and vegetation. Thirty one million hectare area show severe soil acidity problems (pH 5.5) and 59 million ha. have pH between 5.6 and 6.5 (Sharma and Sarkar, 2005). Laterites and various latosolic soils are the large groups among acid soils. The other groups are podzolic soils, brown forest soils, peaty soils etc., Distribution of acid soils in different states of India is given in (Table 1 and Figure 1). Acid soils usually have problems associated with aluminium, iron and manganese toxicity, low nutrients status, nutrients imbalance and multiple nutrient deficiencies.

Organic soils contain _____ % or more of organic matter.

A. 10       B. 15

C. 20      D. 30

1. Anthracnose
Colletotrichum gloeosporioides (Glomerella cingulata)
Diagnostic Symptoms
• Disease produces symptoms like leaf spot, blossom blight, withertip, twig blight and fruit rot .
• Symptoms on leaves show as gray to brown spots with dark margins and a yellow halo. The spots later enlarge and coaleasce to form sizable necrotic areas.
• Tender shoots and foliage are easily affected which ultimately cause die back young branches.
• Blossom blight may vary in severity from slight to a heavy infection of the panicles .
• Black spots develop on panicles as well as on fruits. Severe infection destroys the entire inflorescence resulting in no setting of fruits.
• Young infected fruits develop black spots, shrivel and drop off.
• Fruits infected at mature stage carry the pathogen into storage and cause considerable loss during storage, transit and marketing (Figure -1).

Mango (Mangifera indica L), the king of fruits, is cultivated throughout a wide range of frost-free climates (Litz 1998). It is commercially the most important fruit crop of India, accounting for more than 54% of the total mango production worldwide. The fruit of mango (Mangifera indica L.) is exceptional for its juicy, succulent, thick fruit pulp and nutrient abundance in terms of wide range of amino acids, sugars, organic acids, minerals including Ca, P, Fe, and K and vitamins. Out of several diseases which attack mango crop, mango malformation disease is a serious threat to its cultivation since it causes gross deformation of the vegetative and floral tissues (Ploetz et al., 2002; Kumar et al., 2011). Floral malformation is a major problem in mango, rendering mango cultivation unproductive in northern India and other regions of the world (Pandey et al., 1977; Ram, 1991).

Important Commercial Mango Varieties

Northern Region: Langra, Dashehari, Chausa, Bombay Green, Amrapali, Sukul, Sipia

Eastern Region: Himsagar, Langra, (syn. Malda), Krishna-Bhog, Zardalu, Gulabkhas, Fazli.

Southern Region: Banganapalli, Bangalora, Mulgoa, Neelum, Swarnarekha,

Western Region: Alphonso, Kesar, Pairi.

It is a very common disease of mango. It is otherwise known as blossom blight, leaf spot, twig blight or wither tip.

Origin and history: Mango is the king of fruits which is grown in India for over 400 years. More than 1000 varieties exist today. It grown in almost all state, India’s share is about 56% of total mango production in the world. Its production has been increasing since independent contributing 39.5% of total fruit production in India. Andhra Pradesh top in the production and Uttar Pradesh is top in area. Andhra Pradesh, Bihar, Uttar Pradesh, Karnataka, West Bengal and Gujarat together contribute for about 82% of total production. 

Climate and Soil: Mango thrives well in tropical and subtropical climate. High humidity, rainfall and frost during the flowering period is harmful. The favourable temperature for its cultivation is about 24-27^ºC however, it can tolerant to the temperature up to 48^ºC.

Mango Fruit fly : Bactrocera dorsalis : Tephritidae

This is probably the most economically important pest of mango. It can attack many crops like mango, guava, peach, apricot, cherry, pear, ber, citrus, banana, papaya, avocado, passion fruit, coffee, melons, jack fruit and strawberry. There are also related species that may cross infect. The adults are light brown small flies with a single pair of membranous transparent wings. The other pair is modified into halteres. Eggs are thrust into the skin of the mangoes when they are semi ripe. A drop of resin comes out of the ovipunctures and can be seen as a black mark. While purchasing mango, this can be used as an indication of the presence of the fruit fly eggs.

Basic Requirements

Hybrid seeds could be produced at cheap rates only if the crop species have certain built-in morphological or physiological mechanisms, suitable for the control of parentage for successful hybrid seed production and its floral morphology, is amenable to it. Some of the basic requirements and techniques employed in large-scale commercial hybrid seed production of crop plants are as follows:

• Availability of a proven heterotic hybrid combinations which could distinctly and profitably surpass the yield levels of commercial variety being grown.
• Availability of an easy, economic and effective means of eliminating or rendering functionless of male part of bisexual seed parent, mechanically, genetically or even biochemically.
• Availability of a strong fertility restoration system (in case of the use of cytoplasmically governed male sterility system) or availability of a tightly linked marker gene system in genetically governed male sterility along with full and detectable expression of self-incompatibility.
• Absence of modifier genes or gene systems in case of the use of self-incompatibility for hybrid seed production.
• Complete synchronization of flowering in both seed and pollen parents.
• Free, unrestricted and natural transfer of pollen from pollen to seed parents.
• Good seed setting on seed parent.
• A skilled organized effort for large-scale seed production, certification, processing and well-knitted distribution of hybrid seeds.

Manila tamarind (Pithecellobium dulce  (Roxb.) Benth.), also known as ‘Jangle jalebi’, ‘Madras thorn’, Sweet inga and ‘Monkey pod’ has a potential to become an important tree of semi- arid and arid regions since it is a drought hardy plant and tolerates harsh environmental conditions as well as salinity. In general, it is planted on the boundary of orchard, road and field sides as protective hedge plant. It is a medium size, much branched tree, suitable for silvi-pastoral system (Gupta et al., 1994). It is drought resistant species but susceptible to frost under arid conditions, coming up well in areas of low rainfall due to its extensive root system. Names like dulce (sweet) and “Manila tamarind” reflect the wide use of the pods as food. The most valuable and commonly used part of Manila tamarind tree is the pulp, which is white or red, very sweet and has a pleasant flavour. The large aril represents 50 per cent of the fruit (Seeds 25%, husk 25%). The major constraint in commercialization of this tree species is lack of improved genotypes, agro-techniques for cultivation in different ago-climatic conditions and limited commercial value.

Abstract

Among the different hand thinning treatments, thinning of lateral flower buds resulted in maximum yield of ‘A’ grade fruits (42.30 kg/vine) without affecting the total yield (86.34 kg/vine). The fruit size and weight was significantly increased with increase in the intensity of thinning. The maximum fruit size (length and breadth) and weight were recorded when only two flower buds or flowers, or fruitlets/fruiting shoot were retained, but the total yield was significantly reduced as compared to other treatments. In the second experiment, hand thinning treatment was integrated with the plant growth regulators i.e. CPPU and cytokinin. The results revealed that 5 ppm CPPU in combination with hand thinning (thinning of lateral flower buds to 2 flower buds/fruiting shoot) significantly increased fruit size, yield and percentage of ‘A’ grade fruits. This treatment produced 75 per cent ‘A’ grade fruits as compared to only 19 per cent under control.

Soil fertility and crop production can be maintained only by efficient and judicious management of nutrients addition to the soil from external sources. Of the two sources most widely used all over the world, one is organic in nature- the organic manures, simply called manures, and the other comprises the synthetic or naturally occurring chemical fertilizers, simply called fertilizers. A brief account of manures is described hereunder:

The word manure came from Middle English manuren meaning to cultivate land, and initially, from French word manoeuvre meaning hand work alluding to the work which involved manuring land. The term manure originally meant that which was worked by hand (Fr. manoeuvre), but gradually, came to apply to any process by which the soil peroperties could be improved. Prominent among such processes was that of directly applying manure to the land, manure in this sense being what is now called farmyard manure or dung, the excreta of farm animals mixed with straw or other litter. Ronald Fisher seems to have used the word manure systematically for what we would call fertilizer today.

Uses of Manure

Manure has been used for centuries as a fertilizer for farming since it is rich in nitrogen and other nutrients, which facilitate growth of the plants. Liquid manure from pig or hog operations is usually knifed (injected) directly into the soil to reduce the unpleasant odours. Manure prepared from hogs and cattle is spread on fields using a manure spreader. Due to the relatively lower level of proteins in grasses, which herbivores eat, cattle manure has a milder smell than the dung of carnivores, e.g., elephant dung is practically odourless. However, due to the quantity of manure applied to fields, odour can be a problem in some agricultural regions. Poultry droppings are harmful to plants when fresh but after a period of composting are valuable fertilizers.

The dried manure of animals has been used as fuel throughout history. Dried manure (usually known as dung) of cow was and still is an important fuel source in countries such as India, while camel dung may be used in treeless regions such as deserts.

Soil map is a map showing diversity of soil types and its properties such as pH, texture, organic matter and depth of horizons in the area of interest obtained as the end of soil survey. Generally, soil maps are used to simply identify soils and their properties, but are sometimes required for more specific purposes, such as the suitability of soils for a particular crop, suitability for irrigation, erosion risk and many other specific needs or environmental threats.

Soils fulfil many functions important for agriculture, forestry and the management of soil resources and natural hazards. The functionality of soils depends on their properties; hence, accurate and spatially highly resolved maps of basic soil properties such as texture, organic carbon content and pH for specific soil depth are needed for the sustainable management of soils. The surface soil organic carbon (SOC) concentration is a useful soil property to map soils, interpret soil properties, and guide fertilizer and agricultural chemical applications.

Traditionally farmers apply fertilizers, chemicals and other crop production inputs to optimize the production of the field as a whole. This results in application of over application of inputs and low inputs in certain locations of the field because of variation in field characteristics including soil organic carbon, soil texture, soil nutrients, field topography, and other properties. In addition, uniform applications may increase the chances of pollution of the environment due to excess application in some field area. Precision farming technology has been shown to optimize application rates if the variation of field characteristics can be used to guide the application rate of crop-production inputs. The organic carbon concentrations of surface soil have been used to spatially vary the application rate of some crop-production inputs. The surface soil organic carbon concentration affects the activity of many herbicides, influences plant-available nitrogen and also affects the soil’s ability to adsorb plant nutrients. Knowing its concentration may therefore be useful, especially if its spatial distribution could be determined accurately and for low cost.

In India marigold is one of the most commonly grown flowers and used extensively on religious and social functions in different forms. Because of their ease in cultivation, wide adaptability to varying soil and climatic conditions, long duration of flowering and attractively coloured flowers of excellent keeping quality, the marigolds have become one of the most popular flowers in our country. Flowers are sold in the market as loose or as garlands. Due to its variable height and colour marigold is especially use for decoration and included in landscape plans.

1) Botrytis Gray Mould
Diagnostic Symptoms
• Appearance of a gray, fuzzy mold leaves, stems and on flowers of or plants. Also called, “gray mold”.
• Spotting or blight on leaf and flower stem lesions, and dieback.
• Flower parts become necrotic and die(Fig-1).
Etiology
Domain : Eukaryota
Kingdom : Fungi
Division : Ascomycota
Class : Leotiomycetes
Order : Helotiales
Family : Sclerotiniaceae