In this article we will discuss about the external and internal symptoms of virus infection in plants. External Symptoms of Virus Infection: These are further divided into two main categories: (a) Primary symptoms and (b) Systemic symptoms. (a) Primary Symptoms: These are the initial symptoms and are the result of local reaction at the spot of inoculation. These symptoms appear [...]
Let us make an in-depth study of the structure, distribution and role of isoprenoids (Terpenoids) as secondary metabolites in plants. 1. Monoterpenes (C10): These terpenes contain 10-C atoms and are built up of two iso- preneitnits. There structure may be (i) acyclic, (ii) cyclohexanoid (mono, bi or tricyclic) and (iii) cyclopentanoid. Monoterpenes are chiefly found in resin ducts in leaves, [...]
The following points highlight the three groups of nitrogen containing secondary plant products. The products are: 1. Alkaloids 2. Cyanogenic Glycosides and Glucosinolates and 3. Non-Protein Amino Acids. 1. Alkaloids: Alkaloids are an extremely heterogeneous group of so called secondary metabolites containing one or more nitrogen atoms, usually in a heterocyclic ring. However, all compounds with heterocylic ring and containing [...]