Medicinal plants have been curing various turmoils in animals and human from the time immemorial and are considered an intermittently associated and integral part of Indian Traditional Medicinal system. Modern day man-made drugs often show some detrimental effects, but the medicinal herbs are very safe and easy to access. All over the tropical countries, large scale destruction of the forest and wild due to population pressure and over exploitation of medicinal plants have major threat to important bioresources. The studies on propagation of RET plants have received much interest in recent years; but little attention has been given to rare and endangered plants. Regarding the conservation of RET medicinal plants, the knowledge about the mode of propagation is a priority as most of the endemic and RET medicinal plants lacks definite protocol for their propagation and subsequent multiplication. The studies on conservation through conventional propagation are regarded as one of the most effective methodologies for the sustainable supply and thereby enhancing their resources base.

Sirumalai, locally known as small hill located in Dindigul district, Tamil Nadu and lying between 10 07'-10 18' N and 77 55'-78 12' E. Sirumalai is an isolated compact group of hills which extends between 6.5 km south of Dindigul town and 22.5 km north of Madurai city.Medicinal and Aromatic plants (MAPs) are produced and offered in a wide variety of products, from crude materials to processed and packaged products like pharmaceuticals, herbal remedies, tea, spirits, cosmetics, sweets, dietary supplements, varnishes and insecticides. There were 235 species of medicinal and aromatic plants belonging to 202 genera and 87 families reported from the different forest areas of Sirumalai hills. Among the 235 species, 178 medicinal plants and 57 medicinal and aromatic plants were included. The plants were reported with its common/vernacular name, morphology of parts used, description, chemical constituents and medicinal / commercial properties. There were 93 trees, 34 shrubs, 85 herbs, 22 climbers and one epiphyte with medicinal properties reported from the present survey.The present survey also will helpful for the conservation and sustainable utilization of these species

Increase in the number of people with poor health has made the alternative medical practitioners and pharmaceutical companies to exploit many important medicinal plants. Among these, some rare medicinal plants are also under severe threat due to unscientific management practices, ever increasing demand for its phytochemicals, poor seed viability and over exploitation of the plant parts like bark, flowers, seeds etc., which has resulted in the dwindling of population of RET plants in the wild. By considering the promising medicinal important and its limited distribution, an efficient and reproducible method of micro propagation through shoot tip, nodal and inter nodal explants of six medicinally important rare species has been developed. The book have detailed information on the protocol for the multiplication of some medicinally promising plants. This direct method would be highly useful for the conservation of this vulnerable species from extinction.

Presence of heavy metals in the soil and water is an inevitable evil in modern day due to industrialization. Heavy metal stress is one of the major abiotic stresses that cause environmental pollution in recent decades. These metals unlike other organic pollutants are not degraded and converted into harmless compounds via biological processes. Hence, they can persist for a long time in the environment and enter into food chain. The effects of aluminium and zinc on growth and Biochemical components were investigated in 20 days old seedlings of Pennisetum americanum (L). Leek and Phaseolus aureus in Hoagland's solution spiked with various concentrations of aluminium and zinc. Total chlorophyll content, glucose and protein declined progressively with increasing the concentration of heavy metals. A significant increase of proline, amino acids and other enzymes were detected in primary leaves after exposure to heavy metals. The strongest effect on these chemicals was found in plants exposed to Aluminium.

Soil salinity is a major constraint to food production because it limits crop yield and restricts use of land previously uncultivated.Ubiquitously, no toxic substance restricts plant growth more than does salt. Salt stress presents an increasing threat to plant agriculture. Among the various sources of soil salinity, irrigation combined with poor drainage is the most serious, because it represents losses of once productive agricultural land.The mechanism of plant salt tolerance is a topic of intense research in plant biology. The book covers detailed information to understand the control of ion homeostasis and osmotic regulation, and to use the knowledge to engineer crop plants with enhanced salt tolerance.