eChapters

Seed handling ensures the potential utilization of seed material. Collection and utilization of quality seeds are indispensable in producing quality planting material and better seedling establishment. After selecting the quality seed source, collecting good quality seeds physiologically and genetically is considered the first step in seed handling, followed by processing seeds, testing, storage, and pre-treatment for germination. The main goal of seed handling is to attain an excellent seed survival rate. The chances of seeds getting damaged during any stages of seed handling because of careless or rough approaches are very high.

From the regeneration point of view, the quantity of seed production per tree correspondingly has a vital role to play. If considered virtually, only one successful seed (or two if the species is dioecious) would serve to replace the parent tree(s); hence the production of seeds during the lifetime of a tree is absurd. A full-grown Eucalyptus camaldulensis tree may produce a million or more seeds per year and live further, producing seeds for over a century. Each year’s production could help afforest

The forest cover in most tropical countries has been under severe pressure and is diminishing at an alarming speed; consequently, they are experiencing severe biodiversity losses, reverting to a mature state at a slower rate with low resiliency. These tropical countries are aware of the danger causing due to the loss of forests, and large afforestation programmes have been launched by forest departments, private companies, and donor-supported projects. Nevertheless, plantation activities have rarely been able to keep pace with the deforestation rate, not to mention replacing what has been lost during the past. Plantation programme through afforestation activity is not only the matter of the forest department alone but also the combined responsibility of all the foresters. The appeal of forest planting has changed over the years following the broader demand spectrum.

To some extent, the forest plantations fail to create the diversity of plants and wildlife that has been lost. Hitherto, large-scale plantations are still necessary both directly to cater to the needs of industrial wood and help to minimize the pressure on the remaining natural forests. During the past decades, many government programmes have emphasized using 

Global warming is the hottest issue facing life in our times. The gradual average increase in air temperatures near Earth’s surface over the past one to two centuries is leading to the phenomenon called global warming. It is this global phenomenon that triggers climate change, threatening the entire life on Earth. Earth’s climate has changed over all conceivable geological timescales, but that was all on account of the natural phenomenon. But, human activities are making the phenomenon more pronounced since the beginning of the Industrial Age, now emerging as a dominant triggering factor in influencing the overall climate fabric of the planet.

Radioactive pollution is largely attributable to radioactivity, a natural property of certain elements, such as radium, uranium, thorium, etc. of spontaneously emitting protons (alpha particles), electrons (beta particles), and gamma rays (short-wave electromagnetic waves) through the disintegration of their atomic nuclei (nuclides).

An alpha particle consists of two protons and two neutrons, which is akin to a helium nucleus. Alpha particles travel at a very slow speed, whereas gamma rays propagate at the speed of light. The alpha particles have less penetration power than the beta and gamma rays. In human tissues, alpha particles can penetrate up to a depth of about 0.005 to 0.008 cm. The gamma rays, on the other hand, are the most penetrating and can easily pass through a human body without striking anything in between. The high penetration power of gamma rays is because they have no charge; therefore, they do not interact with anything as the charged alpha particles would do

A sound is a form or energy. Therefore, it has to have an impact on life in one way or the other. Most of the organisms of Kingdom Animalia communicate with each other creating a peculiar sound. Creating sound is inevitable for performing various life activities. Every animal species has the characteristic sound it reflects through its behavior. Whatever all the animals communicate through creating specific sounds is all-natural. Nature, as such is a stupendous repository of a diversity of sounds, all being specific characteristics of life.

Human behavior, however, is highly evolved in terms of creating a variety of sounds. Communication, entertainment, and many behavioral activities are expressed through creating distinctive sounds. There is a difference between natural sounds and the ones human beings create or can create. Humans often generate sounds, not just in a natural manner, but also with various technical aids, that often become unpleasant what we call noise. Creating noise, or noise pollution, seems to be an exclusive characteristic of the human species. Of course, there could be some natural sounds that might occasionally cause havoc to life. Examples are the sounds generated at the time of the volcanic eruption, during an earthquake

Life on Earth is rooted in soil. Soil is not just a substratum anchoring the plants and giving a base for all terrestrial animals. It is the largest terrestrial ecosystem, and one of the most wonderful ecosystems on Earth. It inhabits most microorganisms. Microbial populations flourishing within the soil have greater biomass than all the human beings, elephants, and whales put together. It is due to the microorganisms that the soil constitutes the most active ecosystem on Earth.

The health of the soil is crucial for the health of all the plants growing on it and for all the animals dependent on it for their inhabitation and nourishment. Soil health is also critical for the well-being of numerous microorganisms, detritivores, and several other organisms. Soil is composed of all essential nutrients/ minerals, air, water, and organisms in a proportion that strikes its ecological balance and maintains its structure and functions revealed through its productive potential.

Soil, like all other ecosystems, is itself a dynamic ecosystem. Its composition keeps changing but natural inbuilt mechanisms help strike a balance and recover 

Ours is a Living Planet because ours is a Water Planet. The health of the Living Planet depends on the health of its water resources. Ironically, the health of its water resources is at stake. And so of its life! The waters of the Earth are in the grips of pollution. Much of the water is already polluted and the rest is increasingly becoming polluted. Water pollution, indeed, is one of the worst problems life on Earth is faced with. Water pollution is halting human progress and is phenomenally affecting all walks of human civilization. Water pollution is even putting a question mark on our sustainable future. This chapter presents the causes, magnitude, and consequences of water pollution and also suggests ways and means to prevent and control water pollution and also attempts to manage water resources.

Air or atmosphere constitutes one of the integral components of the environment. Among all the environmental components, the air has the highest fluidity. Therefore, the entry of a foreign substance into the air imparts a quick and severe effect on the health of the organisms. Air in the biosphere has a mixture of various gases in a dynamic proportion which is conducive to maintaining the health and sustenance of all living organisms. An alteration in the composition of the atmosphere beyond a certain limit adversely affects organisms’ health, and might even be of more serious consequences for life.

Air pollution, thus, is defined as the occurrence of undesirable gases (e.g., carbon monoxide, sulfur dioxide, etc.) or particles (e.g., suspended particulate matter) in such concentrations that are deleterious to terrestrial life (vegetation, animals, and human beings) and some physical assets, like buildings, statues, and monuments. Air pollution especially affects the health of human beings living in highly modified (anthropogenic) ecosystems, e.g., cities and industrial areas.

We are living in a world that is in a grim state of environmental disruptions. Callous developmental activities resulting in pollution of all environmental components and gradually culminating in global warming, climate change, and species extinction are responsible for triggering the processes of environmental disruption. Pollution of air, water, and soil is rapidly assuming alarming proportions.

The very processes of socioeconomic development are now posing threat to economic progress as well as to human health. Ominous changes in global climate are posing threat to life on Earth. The irony is that the major cause of environmental disruptions is anthropogenic rather than natural. Human’s materialistic progress and environmental pollution in our contemporary world go hand in hand.

Example: Isolation and Characterization of Protease Inhibitor Gene and Promoter from Black gram (Vigna mungo L.) and Genetic Transformation and Molecular Analysis of Transgenic Tobacco

The genetic information which makes up the genes of higher plants is stored in DNA sequences of the nuclear chromosomes and the organelle genome. There is such an enormous amount of DNA in higher plant cell, that no two organisms are likely to be identical in DNA base sequence. 

Developments in recombinant DNA technology have made it possible to transfer gene from any source across species barrier. In fact, transfer and expression of foreign genes in plant cells is now a routine procedure. Of the several methods tried so far, the system based on Ti plasmid of Aprobacterium tumefaciens appears to be most successful for transformation of plant cells.

Protoplasts are cells which have had their cell wall removed, usually by digestion with enzymes. Cellulase enzymes digest the cellulose in plant cell walls while pectinase enzymes break down the pectin holding cells together. Once the cell wall has been removed the resulting protoplast is spherical in shape. Digestion is usually carried out after incubation in an osmoticum (a solution of higher concentration than the cell contents which causes the cells to plasmolyse). This makes the cell walls easier to digest. Debris is filtered and/or centrifuged out of the suspension and the protoplasts are then centrifuged to form a pellet. On resuspension the protoplasts can be cultured on media which induce cell division and differentiation.

DNA can be sequenced in both double stranded and single stranded templates by cloning in plasmid or phage vectors. There are two sequencing methods.

M13 is a single stranded filamentous DNA phage. Vectors have been developed from M13 phase by Joachim Messing (1983), which are suitable for preparation of single stranded DNA required for sequencing by Sanger’s method. These are derivatives of M13 wild type (size 6.407 kb).

The polymerase chain reaction (PCR) is a very powerful new method used for in vitro to amplify a deoxynibonuclic specific region that lies between two regions of known DNA sequence single molecule to million folds in short time. This is achieved by an enzyme taq. DNA polymerase which is thermostable using this enzyme can synthesize microgram quantities of DNA of specified length and sequence from pictogram quantities of complex template in a few hours time.

Complementary DNA (cDNA) is a double stranded DNA which is an exact copy of the mRNA, i.e. it consists of group of molecules possessing the information contained in various mRNAs but with termini equivalent to or related to those produced by restriction endonucleases. The use of cDNA is an absolute prerequisite for the expression of eukaryotic proteins in bacteria.

Recombinant DNA is advancement in molecular technology which allows manipulation of genomes of higher organisms and dissection of their complex regulatory circuits. This new methodology is being used to understand the biochemistry of living organisms. The isolation of gene begins with the cloning of fragmented DNA of the organism into appropriate vector. 

Exchange of genetic material rarely occurs between unreleated organisms and even similar species may not exchange chromosomal genes. A certain degree of DNA sequence homology is a prerequisite for genetic recombination in vivo. However, recombination between DNA molecules in vitro is not subject to such taxonomic restrictions.

Nucleic acid hybridization requires denaturation i.e. the breakage of H-bridges between the complementary strands of the DNA either by heating at high temperatures or by treatment with denaturing chemicals like formamide. The restricted DNA, therefore, is denatured before transfer from the gel onto synthetic membrane since only single stranded DNA binds to nitrocellulose.