Plant Interaction

... Anjana Bhatia • Saroj Arora • Bikram Singh • Gurveen Kaur • Avinash Nagpal ... More popularly known as ''Ratanjot'' in the northwestern Himalayas, the extract from roots has been used as a dark maroon natural colorant in syrups, tonics, ointments and hair dyes and also for ...

The rhizosphere is the volume of soil under the influence of plants roots, where very important and intensive microbe–plant interactions take place. These interactions can both significantly influence plant growth and crop yields and have biotechnological applications. The rhizosphere harbors a diverse community of microorganisms that interact and compete with each other and with the plant root. The activity of some of the members of this community affects the growth and the physiology of the others, as well as the physical and chemical properties of the soil. Among all these interactions, those resulting in symbiotic and non-symbiotic nitrogen fixation are considerably important. In recent years, the use of bacteria (rhizobacteria) to promote plant growth has increased in several regions of the world and has acquired relevant importance in developing countries that are the producers of raw materials for food. Rhizobacteria can affect plant growth by producing and releasing secondary metabolites, which either decrease or prevent the deleterious effects of phytopathogenic organisms in the rhizosphere, and/or by facilitating the availability and uptake of certain nutrients from the root environment. Significant increases in the growth and yield of agriculturally important crops in response to inoculation with rhizobacteria have been reported. This practical application of plant growth-promoting rhizobacteria is the main focus of this chapter.

Plants used in traditional medicine have stood up to the test of time and contributed many novel compounds for preventive and curative medicine to modern science. India is sitting on a gold mine of well recorded and traditionally well practiced knowledge of herbal medicine. Specially, plants growing at high altitude in Himalayan pastures are time-honored sources of health and general well being of local inhabitants. As of today, Himalayan plants are a major contributor to the herbal pharmaceutical industry both of India and other countries. Plants growing at higher altitudes are subjected to an assault of diverse testing situations including higher doses of mutagenic UV-radiation, physiological drought, desiccation and strong winds. Plants interact with stressful environments by physiological adaptation and altering the biochemical profile of plant tissues and producing a spectrum of secondary metabolites. Secondary metabolites are of special interest to scientists because of their unique pharmacophores and medicinal properties. Secondary metabolites like polyphenols, terpenes and alkaloids have been reported to possess antimutagenic and anticancer properties in many studies. The fundamental aspiration of the current review is to divulge the antimutagenic/anticancer potential of five alpine plants used as food or medicine by the populations living at high altitudes.

A widely acknowledged risk associated with transgenic crops is the possibility that hybridization with wild relatives will cause fitness-related transgenes to persist in wild populations. If wild plants acquire transgenes coding for resistance to herbivory, disease, environmental stress, and/or commonly used herbicides, they could become more abundant in their natural habitats or invade previously unsuitable habitat. In addition, wild populations

The present status of research on the molecular basis of microbe-plant interactions is discussed. Principles and mechanisms which play a role in the interactions of microbial pathogens, biofertilizers, phytostimulators, rhizoremediators and biocontrol agents with the plants are treated. Special emphasis is given to colonization, phase variation, two-component systems, quorum sensing, complex regulation of the syntheses of extracellular enzymes and secondary metabolites, Type 4 pili and Type III and Type IV secretion systems.

A widely acknowledged risk associated with transgenic crops is the possibility that hybridization with wild relatives will cause fitness-related transgenes to persist in wild populations. If wild plants acquire transgenes coding for resistance to herbivory, disease, environmental stress, and/or commonly used herbicides, they could become more abundant in their natural habitats or invade previously unsuitable habitat. In addition, wild populations

The rhizosphere is the volume of soil under the influence of plants roots, where very important and intensive microbe–plant interactions take place. These interactions can both significantly influence plant growth and crop yields and have biotechnological applications. The rhizosphere harbors a diverse community of microorganisms that interact and compete with each other and with the plant root. The activity of some of the members of this community affects the growth and the physiology of the others, as well as the physical and chemical properties of the soil. Among all these interactions, those resulting in symbiotic and non-symbiotic nitrogen fixation are considerably important. In recent years, the use of bacteria (rhizobacteria) to promote plant growth has increased in several regions of the world and has acquired relevant importance in developing countries that are the producers of raw materials for food. Rhizobacteria can affect plant growth by producing and releasing secondary metabolites, which either decrease or prevent the deleterious effects of phytopathogenic organisms in the rhizosphere, and/or by facilitating the availability and uptake of certain nutrients from the root environment. Significant increases in the growth and yield of agriculturally important crops in response to inoculation with rhizobacteria have been reported. This practical application of plant growth-promoting rhizobacteria is the main focus of this chapter.