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Abstract:From the flowers of Sarcococca coriacea, a triterpenoic acid, oleanolic acid, a pentahydric sugar alcohol, xylitol along with the mixture of steroidal glycosides, stigmasterol-3-O-β-D-glucopyranoside and β-sitosterol-3-O-β-D-glucopyranoside have been isolated by chromatographic technique. Their structures were established on the basis of IR,

Biotic and biotic constraints are yield limiting factors in maize producing regions. Among these gray leaf spot is a yield limiting foliar disease of maize in high land regions of Asia. This review is done from related different national and international journals, thesis, books, research papers etc. The objectives of this review are to become familiar with genetics and inheritance, epidemiology, symptoms and disease management strategies etc. High relative humidity, temperature, minimum tillage and maize monoculture are important factors responsible for disease development. The sibling species of Cercospora zeae-maydis (Tehon and Daniels, 1925) Group I and Group II and Cercospora sorghai var. maydis (Chupp, 1954) are associated with this disease. Pathogens colonize in maize debris. Conidia are the source of inoculums for disease spread. Severe blighting of leaves reduces sugars, stalk lodging and causes premature death of plants resulting in yield losses of up to 100%. Disease management through cultural practices is provisional. The use of fungicides for emergencies is effective however; their prohibitive cost and detrimental effects on the environment are negative consequences. The inheritance of tolerance is quantitative with small additive effects. The introgression of resistant genes among the crosses of resistant germplasm enhances the resistance. The crosses of resistant and susceptible germplasm possess greater stability than the crosses of susceptible and resistant germplasm. The development of gray leaf spot tolerant populations through tolerance breeding principle is an economical and sustainable approach to manage the disease.Journal of Maize Research and Development (2015) 1(1):71-85DOI: http://dx.doi.org/10.5281/zenodo.34286

Formylation and acetylation of 7-t-butyl-1,3-dimethylpyrene selectively afforded the 5-mono-and 5,9-di-substitution products depending on the Lewis acid catalyst used, while bromination and nitration afforded the 6-substitution product.

A series of 2,11-dithia[3]metacyclo[3H1,3)pyrenophanes are obtained by the coupling reaction of the corresponding 1,3-bis(bromomethyl)pyrene and bis(sulfanylmethyl)benzenes in ethanol under the high dilution conditions. The conformational studies of dithia[3]metacyclo[3H1,3)pyrenophanes as well as the ring current interactions derived from pyrene ring are described.