eChapters

All the plant biochemical processes are sensitive to change in temperature. Freeze or low-temperature stress in plants becomes lethal when the temperature is lowered beyond a critical threshold for a sufficient duration to cause irreversible damage to plant growth and development. This stress influences countless biochemical reactions which have certain temperature optima for their proper functioning.

One of the important strategies to mitigate the adverse effects of frost is to develop tolerance in plant against frost stress. Tolerance is such a condition of frost vulnerable plant species, they develop certain ability to withstand the freezing stress by avoiding the states of inter or intracellular freezing. Thus, the process of cold hardening or acclimation together with ability to super cool at freezing temperatures is usually termed as frost tolerance development.

The damage due to frost in fruit crops has been a problem for farmers since starting from their cultivation. Damage caused by frost is a worldwide problem because if all aspects of crop production are well managed, one night of freezing temperatures can lead to complete crop loss. According to Bagdonaset al. (1978) frost periods in temperate regions are shorter in duration and occur more frequently whereas in subtropical climates it is occurs with slow moving cold air masses. In tropical regions, there is usually no or very less freezing damage except at higher elevations. In subtropical fruits crops, damages occurs mainly during the winter, whereas in deciduous fruit and nut trees, it occur mainly in spring, but sometimes it occurs in autumn as well. The region prone to frost should adjust the date of planting of crop, microclimate, variety and other preventive measure. According to Attaway (1997) in South Carolina, northern Florida and Georgia, orange fruit were commonly grown before 1835, but losses due to frost damage, farmers did not prefer to grow oranges in that regions. The history of frost damage is more sporadic in nature leading to some major losses from time to time. In December 1990 and 1998

Californiacitrus industry suffered two major damaging events of frost which ranged from little damage in some regions to severe damage in the other region. The economic losses to fruit crops were high in the frost occurring in 1990 compare to frost in 1998.

Key Points

• Frostbite occurs when exposed to freezing temperatures. Animals that are weak and malnourished are more likely to be injured.

• It is a prevalent condition throughout the winter, particularly in animals who do not have shelter or have inadequate protection to protect them from the cold.

• Excessive cold can harm skin and subcutaneous tissue. In severe circumstances, injuries may be irreversible.

Introduction

Frostbite, also known as freezing cold damage, is caused by prolonged exposure to temperatures below 0º C. Exposure to freezing temperatures causes excessive heat loss, disrupting the body's heat balance and resulting in systemic or local acute freezing injury. Frost bites cause superficial tissue injury, but in extreme cases, gangrene develops in the joint or synovial sheath, and the animal dies from toxemia. However, all animal species are susceptible. It occurs rarely in healthy and well-nourished animals. Animals that have lost their coats or are malnourished are particularly vulnerable to harm. Prolonged exposure to colder temperatures increases the risk of frostbite and the severity of the injury. In the majority of cases, frostbite occurs in animals that are left in winter.

1. FRUITS

Fruit is a part of a flowering plant that derives from specific tissues of the flower, mainly one or more ovaries.

1.1. Types

1.1.1. Fleshy

1.1.1.1. Simple fleshy fruits

Develop from a flower with a single pistil.

MANGO

(Mangifera indica, Anacardiaceae; 2n=40, Origin; Indo-Burma)

• India contributes 56% of total mango production in the world
• Highest productivity in the world– Venezuela
• Pollination: House fly (Musca domestica)
• The flower is hermaphroditic with male and female flowers in the same flower panicle.
• Inflorescence-Panicle
• Hybridization work was started by Burns and Prayag in 1911 at Pune in MH.
• Caging technique of breeding was used in Mango by Dr. R. N. Singh.
• In mango, only 0.1% flower develops fruit to maturity.
• The optimum temperature range for its growth and development is 24°C to 27°C.
• It can tolerate up to 48°C during fruit development with regular irrigations, which improve fruit size, quality and maturity.
• For flower bud differentiation, suitable temp is13°C–19°C.
• Mangoes are highly susceptible to low temperature injury/Chilling injury.

Introduction
Fruits and vegetables are an important part of the human diet as they provide the necessary nutrition, essential minerals, vitamins, antioxidants, dietary fiber, etc., required for maintaining proper health. India is the second largest producer of fruits and vegetables in the world after China. Comparison of area under horticultural crops during 2011-12 and 2021-22 indicate substantial improvement from 18.5 million ha to 27.6 million ha with a simultaneous increase in production from 215.04 million MT to about 333.25 million MT respectively in the country within a span of just one decade (Table 1.1). The credit for this spectacular growth in area and production goes to the sustained efforts of the central and state governments for the launch of several farmers’/ growers’ welfare schemes viz., National Horticulture Mission (NHM), Horticulture Mission for Northeast and Himalayan states (HMNEH), Mission for Integrated Development of Horticulture (MIDH); R&D support by the ICAR and State Agriculture & Horticulture Universities, extension agencies/Krishi Vigyan Kendra and proactive farmers and orchardists. However, the increase in production has still not kept pace with the improvement in infrastructure for post-harvest handling, management, processing, and value addition. Various studies still indicate that under normal conditions more than 15-20% of the produce goes to waste from production to consumption which in monetar terms accounts for huge economic losses. A recent study sponsored by the Ministry of Food Processing Industries Government of India and conducted by NABARD Consultancy Services has indicated that about 19.33 million MT worth Rs 58013.71 Crores of fruit & vegetables goes to waste annually as postharvest loss (4.87-15.05%) in various channels from harvesting to consumption (NABCONS,2022). The condition becomes even worse when there is a glut in the market, road blockades, or seasonal vagaries, and farmers are forced to leave their produce in the field itself without harvesting or dispose it at throwaway prices. Such a situation can, however, be controlled by diverting thisproduce to processing for conversion into a number of value-added products for its later use in human consumption. Thus, processing and preservation of horticultural crops have now become a necessity rather than a luxury.

Major industries constituting the food processing industry are grains, sugar, edible oils, beverages and dairy products. The key sub-segments of the food processing industry in India are dairy, fruits and vegetables, poultry and meat processing, fisheries, food retail etc. Agro processing is the sunrise sector of the Indian economy in view of its large potential for growth and likely socio economic impact specifically on employment and income generation. India has the advantage of being one of the fastest growing economies in the world and it is the largest producer of several agricultural commodities. The food processing sector ranks first in terms of employment and number of factories in operation and third in terms of output.

In India, out of the total production of fruits and vegetables, nearly 76 per cent is consumed in fresh form, while wastage due to improper post harvest accounts for 20 to 35 per cent. Only around 2 percent of vegetables and 4 percent of fruit production are being processed. 

4.1 Introduction

A huge amount of waste in the form of liquid and solid is produced in the fruit and vegetable processing industry which causes pollution problem if not utilized or disposed off properly. Generally solid waste is dumped in local landfills, eaten and scattered by stray animals, which has now become a major cause of environmental pollution. The waste obtained from fruit processing industry is extremely diverse due to the use of wide variety of fruits and vegetables, the broad range of processes and the multiplicity of the product [79]. The solid waste from fruits and vegetables includes peel, stone, rag, seed, core etc is of economic value and can be used for manufacturing of various by-products [21]. The extent of the waste produced from processing industries of some of the important fruits and vegetables, is given in Table 1.

In India, utilization of fruits and vegetables for processing is hardly 1.8% of the total production. There were 5166 processing units till 1^st Jan, 2009 of fruits and vegetables products throughout the country. About 90% of these units are small scale units with annual production limit of 50-250 tonnes. These units have no organized methods of waste disposal. In certain places this waste is taken away by farmers for their disposal as cattle feed or field manure.

Fruits have been one of the earliest foods of mankind. Ancient Indian texts like Charak Samhita and Sushruta Samhita, religious books and puranas are replete with mention of various kinds of fruits. The mango is believed to have been grown for more than 4000 years. Mention of apple, the forbidden fruit, in the Holy Bible is well known. The date-palm is recorded as the fruit crop grown by mankind since 7000 BC. The first book in the world on fruit culture is said to have been the one written on litchi in 1056 AD. In the earlier period of human civilization, fruits served both as food and medicine. Fruits, nuts and tubers were the staples for early wanderers and gatherers. The settled agriculture made mankind more dependent on cereals, pulses and oilseeds for staples and fruits, vegetables and nuts became more a medicine than food.

Many evolutionary and anthropological changes occurred in course of time with changing food habits. At every stage of major change, food habits determined the life expectancy. After completing a full cycle or helix, time has returned to focus on fruits and vegetables again as food, from a stand point of health and wellbeing. From being trees of wild and forests in earlier period, fruit crops became confined to palaces and orchards of Kings in medieval period. In modern Era, it came to stay as commercial commodities dictating the terms of trade. Due to its growing commercial importance the governments across the globe focused to expand the area under fruit crops and cross border trade in several fruits and vegetables. Horticulture research started prioritizing the traits in fruits that determine the economics of trade. In line with these developments, Indian government assigned great significance to horticultural crops since 8^th five-year plan period, and the allocation for horticultural research was increased to `110.2 crores from `31.96 crores in the previous plan. During the 10^th five-year plan period in 2005-06, the National Horticulture Mission was started. As the net outcome of these efforts, the area under fruit crops increased from 2.87 million ha in 1991-92 to 6.48 million ha in 2016-17. The production increased from 28.63 million tonnes to 92.85 million tonnes and productivity from 9.96 tonnes/ha to 14.33 tonnes/ha during the same period (Anon, 2017).

Out of the total value of output of agricultural crops, fruits and vegetables contribute the lion’s share of 23%. The major fruit crops producing states are Andhra Pradesh, Maharashtra, Uttar Pradesh, Gujarat, Madhya Pradesh, Karnataka, Tamil Nadu, Bihar, West Bengal and Chattisgarh. The major fruit crops grown are banana, mango, citrus fruits (sweet orange, mandarin, lime & lemons), peach, guava, papaya, pomegranate, sapota, apple, pineapple, ber, litchi, avocado, etc. Several minor crops like jackfruit, aonla, bael, jamun, custard apple, fig, karonda, phalsa, carambola, etc., are also grown. Some exotic fruit crops like dragon fruit, kiwi, durian, Malayan apple, rambutan, etc., are also getting imported either due to its extra ordinary taste or exotic flavor.

Introduction

The term cropping system refers to cropping patterns used on a farm and their interactions with farm resources, other farm enterprises, and available technology over a fixed period. The fruit based cropping system includes different fruit crops as major component on particular field for a fixed period through intercropping or multistory cropping. Intercropping is growing of two or more crops together on same piece of land simultaneously with definite row arrangements to utilize farm resources efficiently. Multistory/Multitier cropping refers to growing together of  crops of different heights at the same time on the same piece of land and thereby using land, water and space in an efficient and economic manner.

5.1 INTRODUCTION

Drought and rampant poverty, the double plague of arid region, present a scenario of misery and insecurity across the region where agriculture is the main livelihood and chief source for subsistence of the rural people. The conditions of low and erratic rainfall, extreme temperature conditions, high evapo-transpiration, scarce water resources, infertile and saline soils with ill-defined profile development threaten sustainable agriculture. Sustainable productivity is difficult to achieve by monoculture of either seasonal or forage crops. Thus cropping system approach for agricultural production is of far greater significance in these regions. Traditionally efforts have been made by the native people, obviously to achieve sustainable production ensuring ecological stability, to grow several species together, e.g. pearl millet, moth bean, cluster bean and gram between the natural stands of khejri (Prosopis cineraria), bordi (Zizyphus rotundifolia), lasoda (Cordia myxa), pilu (Salvadora oleoides), and ker (Capparis decidua). The perennial species also provide fodder for sheep and goats during scarcity periods.

Fruit based cropping system is now considered to be the most ideal strategy to provide food, nutrition and income security to the people (Chundawat, 1993, Chadha, 2002, Awasthi and Pareek, 2008). Integration of annual crops with fruit trees yields multiple outputs that ensure production and income generation (Randhawa, 1990 and Osman, 2003) in a sustainable manner. Natural resources (land, solar radiation, water, soil etc.) as well as socio-economic inputs (labour, credit, power, and market infrastructure) are efficiently utilized. Crop productivity under tree canopy is enhanced due to improved soil fertility (Young, 1989) and ameliorative influence of shade by reducing understorey temperature and evapotranspiration (Bunderson et al., 1990). Incorporation of fruit trees into the cropping system is more remunerative. It increases the resilience of the system over time. It enables to i) maximize system productivity on annual basis, ii) utilize resources with high efficiency through due consideration of various interactions and direct, residual and cumulative effects occurring in soil-plant-atmosphere continuum, iii) intensify input use vis-à-vis quality of environment, and iv) impart sustainability of farm resources and environment in long term perspective. The type of horticulture based cropping system in arid region has been discussed in this paper considering these issues.

Beverages:-The fruit beverages are easily digestible, highly refreshing, thirst quenching, appetizing, nutritionally for superior than many other synthetic drink. There are two types of fruit beverages i.e. unfermented beverages and fermented beverages. Natural juice, RTS (Ready to Serve), nector, cordial, squash, crush syrup, fruit juice concentrate and fruit juice powder are the main unfermented beverages. The fermented beverages are wine, champaigne, port, sherry, tokay, muscut, neera, cidar, orange wine, berry wine and fenny are the important.

Fruit juices which do not undergo alcoholic fermentation are termed as unfermented beverages. They include natural and sweetened juices, RTS, nectar, cordial, squash, crush, syrup, fruit juice concentrate and fruit juice powder. Barley waters and carbonated beverages are also included in this group.

Fruit crops, majority of them are generally perennial in nature and owing to the outcrossing during their evolutionary stages, they are highly heterozygous. Genetic improvement is extremely difficult due to the complex genetic nature. The germplasm collection, conservation and evaluation take long time and area. Although the concept of core collection is very much valid, there is always a question mark when it comes to highly heterozygous crops as to whether the sample is good enough to represent the population. Due to the propagation by seeds, the large variability present needs to be evaluated for various characteristics. The genetical studies carried out in many of these crops are not conclusive and the progeny performance cannot be predicted. The biometrical methods to estimate the parameters viz., combining ability, heritability using the methodologies such as diallel have proven to be futile excercises to a very great extent. Parental selection, which is so vital for a successful breeding programme is very difficult as mainly selection has to be based upon the phenotype. Breeding for particular traits like biotic or abiotic stress has been difficult as resistance is not found within the spp and interspecific / intergeneric hybridization is difficult because of incompatibility barriers for eg the ‘PRSV’ breeding programme in papaya. In highly heterozygous crop like mango, there exists strong genotype x environmental interaction, which alters the performance of improved varieties.

Indian subcontinent is a mega-center of crop plant diversity, as well as wild relatives and other useful taxa (Zeven and de Wet 1982). Diverse agroclimatic conditions, agricultural practices, and ethnic diversification have resulted in the development of a rich diversity of crop plants among native and introduced taxa (Arora 1991). Fruit crops contribute significantly to nutrition and health because they are high in dietary energy and contain a significant amount of vitamins and minerals (Pareek et al., 1998). Most of these species serve multiple functions, such as food, shelter, timber, fuel, medicine etc. As a result of their numerous applications, tropical fruits significantly contribute to food and nutritional security, income generation, ecosystem and environmental sustainability.

Jammu division with three agro-climatic zones viz., sub-tropical, intermediate (low hills) and temperate (Fig. 1) has vast potential for horticultural industry by way of improving the productivity of existing orchards and using vast tracts of underutilized wastelands, kandi areas of sub-tropical zone and hilly areas of intermediate and temperate zones for fruit production. For this, there is need for plantation of suitable varieties, budded/grafted on proper rootstock and following of improved orchard management practices viz., training and pruning, nutrient and water management and pest and disease control. At present, fruits occupy an area of 118805.00 ha with the production of 274006.70 MT and productivity of 2.31 MT/ha in Jammu division.

Sub-tropical zone

It comprises both irrigated and unirrigated areas and goes upto an attitude of 500 m above mean sea level. This zone is characterized by hot summers and relatively dry but pronounced winters. The land is suitable for cultivation of mango, citrus crops (sweet orange, mandarin particularly kinnow, lime, lemon), guava, litchi, ber, papaya and other minor fruits. Some low chill varieties of temperate fruits like peach, plum, pear and strawberry have been introduced at Advanced Centre for Horticulture Research (ACHR) of SKUAST-J, Udheywalla and peach cultivars Shan-e-Punjab, Flordasun and Flordared and pear cultivars Patharnakh and LeConte have shown good yield and quality crop. Besides, strawberry cultivars Chandler, Gorella, Fern and Belrubi have also shown promising yield with proper management practices. For rainfed areas, hardy fruits like aonla, phalsa, ber, guava, lasoda, karonda and custard apple are more suitable with aonla, phalsa and ber being commercially more viable.

Introduction

Fruits are undoubtedly God’s gift to mankind. Fruits are protective foods as they contain vitamins, minerals and enzymes, necessary for better functioning of human body and for fighting diseases. History of fruits is as old as that of Adam and Eve who ate the forbidden apple. Date palm seems to be the earliest fruit cultivated by man as early as 7000 B.C. Pomegranate is also one of the oldest fruits which was under cultivation as early as 3500 B.C. During ancient times, monks survived solely on fruits and milk giving an indication about importance of fruits and antiquity of fruits in India. India is the place of origin of mango, banana, phalsa, jack fruit, bael, aonla and a few citrus fruits whereas all other fruits are introduced from foreign countries. Litchi, loquat, persimmon, peach and sweet orange are from China; papaya, guava, sapota, avocado, custard apple and pineapple are from tropical America; and apple, plum, pear, date palm, mangosteen, strawberry, cherry, almond, walnut, apricot, grape and pomegranate are from the Central Asiatic Regions.

Introduction

Salinity is an encompassing term used to describe saline and sodic soils, and the marginal quality groundwater unsuitable for crop irrigation. A soil is considered to be ‘salt-affected’ when either excess soluble salts or excess exchangeable sodium or both adversely affect the soil properties and plant growth. Depending on the values of soil saturation paste extract electrical conductivity (EC_e), pH (pH_s) and exchangeable sodium percentage (ESP), salt-affected soils (SAS) are grouped into saline (EC_e > 4 dS m^-1, pH_s < 8.2 and high ESP< 15) and sodic (EC_e< 4 dS m^-1, pH_s>8.2 and ESP >15) categories. Under certain conditions, both excess soluble salts and exchangeable sodium may be present resulting in saline-sodic conditions (EC_e > 4 dS m^-1, pH_s>8.2 and ESP >15)(Sharma and Singh, 2015). Based on FAO/UNESCO soil map of the world (1970-1980), the global extent of SAS was earlier computed to be 831 Million ha (M ha) consisting of 397 M ha saline and the remainder 434 M ha sodic soils. Although this estimate is still widely used, recent studies suggest comparatively higher global extent of salinity and the associated problems; especially in irrigated arid and semi-arid regions across the world. Not withstanding the discrepancies in such estimates, it is certain that salinity continues to impose substantial costs on global food production and environmental sustainability.

Fruit drop is a natural phenomenon, which occurs in most of the fruit crops. Fruit trees usually bear a large number of flowers and only a very small percentage leads to harvesting of fruits. Fruit drop occurs at various stages of maturity of fruit development. It is an adjustment of tree to its resources. Such drop is natural and beneficial to the trees and it will prevent exhaustion of the resources and breaking of branches by overbearing. The fruit drop usually takes place in definite waves or at a definite stage and those are presetting, post setting, jar drop and pre harvest drop.

The first drop i.e. presetting occurs immediately after flower opening. Usually male flowers as well as female/ hermaphrodite flowers with aborted pistil drop off at this stage.

Second drop i.e. post setting occurs a fortnight later than the first drop. This drop includes unfertilized flowers as well as some fertilized flowers drop as a result of adjustment in the trees between nutritional factors arid fruit set.