1. Introduction

Plant biomass plays an important role in sustaining environment and life including human life on earth. The earth system is a closed system except for its absorption of solar energy. Green biomass is the only component of the earth system that captures bursts of solar energy, converts them, and allocates them to flows to other components and consumers of the ecosystem. In an ecosystem, where green biomass is the primary producer, humans occupy almost all positions, primary, secondary, or tertiary, within the consumer chain. Humans derive their essentials – food, fiber, fuel, and fodder – directly from green biomass and indirectly through other primary and secondary consumers of green plants. Hence, performance of green biomass growth in an ecosystem is not only important for smooth functioning of all components of the earth system but also for human existence in a befitting manner.