Environmental Factors Undermine Genetic Expression of Tiller Dynamics in Wild Rice

Tillering is a principal trait for the study of branching and production of more number of panicles for increased grain production in many cereal crops. Most of the semi-dwarf high yielding rice cul-tivars exhibit a remarkable degree of stability with respect to their tillering ability and maintain almost a constant tiller number which is genetically fixed for a particular cultivar. However, tiller production in wild species of rice is largely determined by environmental parameters, which su-persede genetic features for expression of complete tillering ability. Two species of wild rice like Oryza nivara and Oryza rufipogon were tested for influence of manipulated growing conditions on tiller dynamics by comparing their growth in natural habitats and cemented pots filled with ma-nure added soil. The results revealed a significant enhancement in the number of tiller production as well as biomass accumulation of each tiller with more grain yield in the cultivated conditions in both the species in comparison to the wild situations. The dryland inhabitant O. nivara became mono-tillering and deep water species O. rufipogon produced as many as five tillers with relatively lesser grain yield in their natural environments compared to their cultivated counterparts. From these observations, it is concluded that expression of genetic potential for tiller production i