Self-incompatibility system can be divided into two basic groups: 1. Heteromorphic Systems 2. Homomorphic Systems. Group # 1. Heteromorphic Incompatibility: This incompatibility refers to those plants where the same species produces more than one morphological types of flower, where the relative length of the style (distyly and tristyly) and stamens differ. In distyly the plants produce two forms of flowers, [...]
In this article we will discuss about:- 1. Distribution of Sporopollenin 2. Chemistry of Sporopollenin 3. Production and Deposition 4. Functions. Distribution of Sporopollenin: It was first observed and named as "sporonin" by John (1814) and latter characterized by Berzelius (1830). Fossil green algae dating back to Devonian period have been shown to contain sporopollenin. The oldest sporopolleninous acritarchs occur [...]
In this article we will discuss about:- 1. Meaning of Pollen Viability 2. Variations in the Viability of Pollen 3. Causes for the Loss 4. Factors. Meaning of Pollen Viability: Pollen viability refers to the ability of the pollen to perform its function of delivering male gametes to the embryo sac. This functional property of the pollen after their release [...]