eChapters

Respiration is the oxidative breakdown of complex substrate molecules such as starch, sugars, and organic acids normally present in plant cells to simpler molecules such as carbon dioxide and water. Concomitant with this catabolic reaction is the production of energy and intermediate molecules that are required to sustain the myriad of metabolic reactions essential for the maintenance of cellular organization and membrane integrity of living cells. Since respiration rate is so tightly coupled to the rate of metabolism, the measurements of respiration provide an easy non-destructive means of monitoring the metabolic and physiological state of tissues, e.g., the events of senescence and ripening are often signaled by abrupt changes in respiration.

Maintaining a supply of high-energy compounds like adenosine triphosphate (ATP), nicotinamide adenine dinucleotide (NADH) and pyrophosphate (PPi) is a primary function of respiration. Nicotinamide adenine dinucleotide plays very important role in mitochondrial matrix (Moller and Ramusson, 1998). The overall process of aerobic respiration involves regeneration of ATP from adenosine diphosphate (ADP) and inorganic phosphate (P_i) with the release of carbon dioxide and water. If glucose is used diphosphatas substrate, the overall equation for respiration can be written as follows:

Body needs oxygen to oxidise the food nutrients and derive energy. In this process carbon dioxide is produced in the body, which is toxic and must be removed quickly and efficiently. The oxygen utilization & carbon dioxide production takes place within the mitochondrion of cells of the various tissues. The transport of O2 and CO2 to and from the cells of various tissue is done by the blood. But the actual uptake of oxygen from the air and discharge of CO2 into the environment takes place at the level of lungs. This exchange of O2 and CO2 between the organism and the environment is defined as respiration. Air is moved in and out of the lungs by their bellows action (ventilation). It is then distributed within each lung, so that alveoli are adequately ventilated and also perfused by the blood.

Oxygen and carbon dioxide are then exchanged between the gas mixture in the alveoli and the blood in the pulmonary capillaries (gas transfer). The gases are then transported in the blood to the tissue.

It is a most deteriorating biological process of the harvested fruits and vegetables that leads to the oxidative breakdown of the complex material (carbohydrates or acids) of cell into simpler molecules (CO₂ & water) with production of energy. Respiration includes glycolysis metabolism, aerobic metabolism, anaerobic metabolism, trycarboxilic acid cycle and electron transport metabolism processes.

The primary role of the respiratory system is to provide O2 to the tissues for metabolic needs and remove the CO2 formed by them. Body needs oxygen to oxidise the food nutrients and derive energy. In this process carbon dioxide is produced in the body, which is toxic and must be removed quickly and efficiently. The oxygen utilization & carbon dioxide production takes place within the mitochondria of cells of the various tissues.

Respiration rate, irrespective of plant parts (viz. leaves, fruits or seeds), is considered to be an important parameter in plant physiological studies. Respiratory gas exchange is just reverse or opposite to that of photosynthesis and as the later is an energy building phenomenon where ATP is stored in the photosynthates produced; respiration involves breakdown of photosynthates for release of energy to be utilized for the performance of other activities of life. Respiration plays an important role during seed germination. A germinating seed requires a lot of energy which is derived from the breakdown of different types of food reserved in the cotyledons. On the basis of respiration a climacteric fruit can well be distinguished from a non climacteric one; as the former reveals a characteristic ‘Climacteric Burst’ in respiration, which is completely lacking in the later.

There are a few instruments used for the measurement of respiration in plants viz.:

Key Points

• Dogs exhibit respiratory distress symptoms more frequently than cats.

• Respiratory distress might have overt or covert clinical symptoms.

• The thorax and belly move paradoxically in cases of severe respiratory distress.

• Immediate intubation is the first step in managing a respiratory emergency: opening the airway.

Introduction

The telltale symptoms of "oxygen hunger" include tachypnea, stretched head and neck, abducted elbows, flare of the nares, cyanosis, open-mouth breathing, anxiety, and inability to lie down or relax. It is more usual for dogs than cats to exhibit symptoms of respiratory distress. Tachypnea and conspicuous breathing motions when in a sternal recumbency position are the only indications of respiratory dysfunction in cats, who often mask the severity of their illness. Despite their seeming stability, these patients are often extremely vulnerable and can rapidly decompensate when under stress.

The respiratory system or tracheal system is involved in gaseous exchange in the insect with the environment. In this system there is a system of internal tubes, the tracheae that directly transport the oxygen to the parts of the body. Therefore, it does not use the circulatory system as the vehicle for gaseous exchange. The trachae open outside through segmental pores called spiracles having some system of closing and opening. Except proturans and some collembolans all insects possess tracheal system for respiration. These insects live in moist habitats where gaseous exchange takes place directly with the environment via the integument.

The development of the upper respiratory system composed of nasal cavities, naso pharynx and larynx is directly related to the development of the face. The nasal cavities are derived from ectoderm while nasopharynx and larynx are endodermal in origin. The lower respiratory system (trachea and lungs) is a derivative of the embryonic pharynx.

The epithelial lining of the lower respiratory system is endodermal in origin, while the surrounding connective tissue and cartilage are mesodermal in origin. The endoderm and underlying mesoderm from the floor of foregut i.e caudal part of pharynx grow caudally in midline and form the laryngo-tracheal groove at about the level of the branchial arches IV -VI from which the larynx and trachea arise. The laryngotracheal tube consists of an inner endodermal lining and an outer layer of splanchnic mesoderm. It grows into underlying mesenchyme. Ingrowths from the sides of the groove at about the level of the branchial arches IV - VI form a pair of ridges that grow towards each other and fuse forming a septum changing the groove into a tube with a blind end caudally. The rostral end opens into the floor of the pharynx. The blind caudal end expands in a bilobed manner into mesenchyme forming bronchial buds the primordia of right and left lungs while the groove is closing.

larynx : A pair of elevations, aryteniod swellings appears on the floor of the pharynx along midline at the level of branchial arch IV. The hypobranchial eminence is just infront of the arytenoid swellings. The depression between the hypobranchial eminence and the arytenoid swellings becomes the lumen of the larynx. The caudal part of the hypobranchial eminence forms the epiglottis. The arytenoid swellings and adjacent branchial arch mesenchyme form the other laryngeal cartilages and musculature. The thyroid cartilage arises from branchial arches III and IV. The other cartilages are derived from mesenchyme of branchial arches IV, V & VI. The intrinsic musculature of larynx is derived mostly from the branchial arch V and VI. With the exeption of the epiglottic cartilage the cartilages and muscles of the larynx are formed by the end of embryonic period.

The respiratory system is a complex biological system comprised of several organs that facilitate the inhalation of oxygen and exhalation of carbon dioxide (breathing) in living organisms. The major functions of the respiratory system is providing oxygen to the body cells and removing carbon dioxide from the body. In addition to this, the respiratory system helps in controlling body temperature (especially in dogs), eliminating water (as vapour) and assisting in voice production. The organs of respiratory system extend from nose to lungs. These consist of two major parts, the upper respiratory tract and the lower respiratory tract. The upper respiratory tract is comprised of nose, nasal cavity, the part of mouth, and the part of pharynx. The lower respiratory tract is comprised of the larynx, trachea, bronchi and lungs.

Nose

The nose is the externally visible part of the respiratory system. It forms the part of the face of the animal extending from the transverse level of eyes to the rostral end of the head. Exteriorly it is formed by the bones, muscles, cartilages and the skin. Internally it encloses the nasal cavity which is lined by the mucous membrane. The dorsal part of the nose (roof of the nasal cavity) is termed as dorsum nasi. It is formed by the nasal and frontal bones of the skull. The lateral parts are formed by the incisive, maxillary, lacrimal and zygomatic bones. Covering these bones externally is a muscular layer formed by the facial muscles running over these bones and acting on the upper lip and nostrils. The muscular layer is externally covered by the skin. The skin on the nose bears fine hairs except at the tip of the nose that is formed by the nostrils. The rostral end of the nose is formed by nostrils which provide entrance to the nasal cavity. The nostrils are supported by cartilages which are the dorsal and ventral extensions of the cartilage of the nasal septum. The main aim of the nose is to support and protect the nasal cavity.

Among abiotic stresses, low and high temperature stress is very critical for determining the agricultural production. Plants exhibit a maximum rate of growth and development at an optimum temperature or over a diurnal range of temperatures (Fitter and Hay, 1981). When ambient temperature deviates from optimal, physiological, biochemical, metabolic and molecular changes occur within plants. This is an effort of plants to maximize growth and developmental processes and to maintain cellular homeostasis during such adverse conditions. Under increasingly stressful conditions, plants experience progressively more abnormal, impaired or dysfunctional cellular and whole-plant processes until the cardinal temperatures for survival are reached (Fitter and Hay, 1981). At the extremes of the natural temperature range of a plant, the degree of physiological, cellular, metabolic and molecular dysfunction becomes so severe that it leads to death.

Growth constraints and stress result in significant crop losses and therefore the mechanisms underlying endurance and adaptation to these changes have long been the focus of intense research (Bray 2004). Kültz (2005) elaborated two types of responses to a particular kind of stress:

Fruits, vegetables, ornamentals, plantation crops and spices, medicinal and aromatic plants, tubers, are the major horticultural crops contributing to the economic growth in India. Even though the horticultural sector is growing fast, with India being the second largest producer of fruits and vegetables in the world, the productivity and quality have to be improved in order to meet the demand of increasing population. Under these circumstances, ecofriendly techniques needs to be adopted which could ensure food security and sustainable production. Indiscriminate application of agrochemicals and chemical fertilizers in horticultural crops and their residues could harm the human health, soil and environment. Horticultural crops need an ecofriendly technique, as most of the horticultural products are directly consumed. Hence, there should not be any residues of agrochemicals in food products. In the current context, use of ecofriendly, cost effective and organic-based inputs like biofertilizers can maintain health of the soil and good quality in horticultural crops. The application of biofertilizers offers an attractive and sustainable means of improving the quality of food products. Biofertilizers like Azotobacter, Azospirillum and AMF and PGPRs not only supplies the required nutrients to plants, but improves the fruit quality and quantity (Pathak et al., 2017).

Climate change produces long-term alterations in temperature, precipitation, wind and atmospheric carbon dioxide. Because insects are ectothermic organisms, these environmental changes strongly influence their physiology, ecology and behaviour. Rising temperatures can modify development, movement, feeding, mating, reproduction, diapause, migration and survival. Altered rainfall and extreme weather may affect habitat suitability, host availability and interactions with natural enemies. Climate-related behavioural changes can influence pest abundance, crop damage, geographical distribution and the timing of infestations. This chapter examines how insects respond behaviourally to changing environmental conditions and explains why understanding these responses is essential for forecasting pest outbreaks and developing effective climate-resilient crop-protection strategies.

Thus the average value of progeny genotypes in response to selection of parental phenotypes depends largely on Cov (G, g), the genetic covariance of parent and offspring which is half the additive genetic variance of the parents.
We know that on an average, half of genes of a parent are passed to the offspring and with them a random half of his additive merit. One-fourth of his additive x additive gene combinations are also transmitted and lesser fractions of higher additive combinations. No dominance combinations are transmitted, since only one member of each allelic gene pair reaches the offspring. Similarly all epistatic gene combinations involving allelic gene pairs are broken up at gamete formation. If dominance and epistatic gene combinations involving allelic gene pairs are important in determining genetic superiority for the trait, then direct selection of superior parents will not produce genetically superior offspring. Some form of mating system which will recreate these combinations in the offspring, together with the formation of lines or groups within the population is needed in these circumstances.
Thus, the aim of selection is to identify and select as parents individuals with high additive genetic merit. By selecting the parent on additive merit, we also ensure that a fraction of any parallel merit for additive type epistasis is also passed on. In considering response to selection, little is lost by treating the response as if it were wholly determined by the additive effects of genes

The response to selection (R) or selection advance or genetic gain is the difference between the mean phenotypic value of the offspring of the selected parents and the whole of the parental generation before selection. The response to selection is simply the change of population mean between generations following selection. Similarly, the selection differential (S) is the mean phenotypic value of the individuals selected as parents expressed as a deviation from the population mean (i.e., from the mean phenotypic value of all the individuals in the parental generation before selection). Response to selection is related to heritability by the following equation:

The response to selection is the change produced in the population mean through selection. This is achieved through selecting as parents of the next generation, individuals with highest genetic merit and whose progeny will, as a group, have the highest possible genetic merit for the trait in question. 

India is situated north of the equator between 8°4' and 37°6' north latitude and 68°7' and 97°25' east longitude, is the largest peninsular country in the world bordered by Arabian Sea in the west, Indian Ocean in the south and the Bay of Bengal in the east. India has a coastline of 8118 km and 0.5 million t sq. km continental shelf endowed with 2.02 million sq. km of Exclusive Economic Zone (EEZ). It has a catchable annual fisheries potential yield of 4.41 million occupying third rank in world marine fish production (Table 1). India’s territorial waters extend into the sea to a distance of 12 nautical miles from the coast baseline. The vital details on marine capture fisheries of India are given in table

In the earlier chapter the major soil vulnerability namely, water and wind erosion, depletion of soil organic matter, loss of plant nutrients, salinity, alkalinity, acidity, pollution and contamination, compaction, sealing, crusting, water-logging, aridity, landslide and abandoned mines were described. In this chapter two more parts, Importance of remote sensing (RS) and geographical information system (GIS) in soils and Watershed management are also included after seeing their importance in agriculture and soils. Restoration means that by various actions or processes to return something to its original owner, site, place, or condition. In this context our aim is to restore our mother soil from various vulnerabilities by different actions and processes to its natural and original condition up to the maximum possible extent. Management is defined as the scientific methods to attain targeted production through planning, organising, training and fixing targets for employees. Therefore, after the restoration, soils should be managed according to scientific method of action by scientifically selected and trained staff to perform the assigned responsibilities, effectively, efficiently and rapidly within stipulated period. On these guidelines restoration and management of vulnerabled soils is described here,

Abstract

In South India, tanks system is quiet ancient, meant for storing and supplying water towards multifunctional needs of the people. In Tamil Nadu, there are around 39,000 tanks with varying size and types. Over past few decades, irrigation rely on stable and reliable groundwater resources like dug and deep bore wells, consequently tanks lost their significance. Moreover, excessive siltation, improper maintenance and illegal encroachment further degraded the system. The deterioration factors are broadly categorised into problems in catchment, feeder channels and head works which eventually resulted in loss of storage capacity. The present study chiefly narrates an indirect method of estimating the loss in storage capacity of tanks and the catchment problem, especially soil erosion and its induced siltation of tanks in the downstream using geoinformatics technology. Using remotely sensed satellite data, by measuring surface area of tank loss in storage capacity was estimated through a linear model. Using Digital Elevation Model derived topographic wetness indices data, the catchment problem especially, soil erosion areas were identified and remedial measures were suggested. Under prevailing water crisis, it is essential to rehabilitate the tanks through which the surface water potential can be improved along with quality as well.

Introduction

Worldwide, salt–affected areas are estimated to range from 340 million ha to 1.2 billion ha (FAO, 2007; Oo et al., 2015; Ahmad et al., 2016; Drake et al., 2016). Millions of hectare of these salt affected soils are suitable for agricultural production but are unexploited because of salinity/sodicity and other soil and water related problems (Abrol et al., 1988). Salt-affected soils are reported to comprise 42.3% of the land area of Australia, 21.0% of Asia, 7.6% of South America, 4.6% of Europe, 3.5% of Africa, 0.9% of North America and 0.7% of Central America (El-Mowellhey, 1998). In India, out of 329 million ha geographical land area of the country about 175 million ha suffers from different problems and is getting further degraded through natural or man-made processes. Majority of these lands is treated as wastelands as their productivity is low due to soil based constraints like water logging, salinity and sodicity. According to FAO, salinization of arable land will result in 30% to 50% land loss by the year 2050 if, remedial actions are not taken. Recent estimates indicate that 6.73 million ha (NRSA and Associates, 1996) land is suffering from salinity and sodicity problems in India. High salt deposits inherited by the soil from the original parent material during soil forming processes and poor drainage are important factors contributing to the development of such soils. These lands occur in different biogeographic zones and therefore consist of diverse morphological, physical, chemical and biological properties. These soils are universally low in fertility and due to the adverse edaphic environment; they are devoid of any vegetation because of excessive exchangeable Na+ associated with high pH (>8.5) which impairs the physical condition of the soils and adversely affects water and air movement, nutritional and hydrological properties of the soils (Suarez et al., 1984; Gupta and Abrol, 1990; Sumner, 1993; Garg, 1998).These lands are largely carbon-depleted but can be brought back to their native carbon-carrying capacity by reforestation through agroforestry systems. The presence of CaCO3 concretions at various depths (caliche bed) causes physical impedance for root proliferation, therefore, making it difficult for tree establishment and restrict the choice of arable crops to be grown (Shukla et al., 2011; Singh et al., 2012a).