TITLE:
Environmental Factors Undermine Genetic Expression of Tiller Dynamics in Wild Rice Oryza nivara and Oryza rufipogon
AUTHORS:
Ekamber Kariali
KEYWORDS:
Oryza nivara, Oryza rufipogon, Tillering, Spikelets
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.5 No.18,
August
7,
2014
ABSTRACT: 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 cultivars 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 supersede 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 manure 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 is
amenable to fluctuation of environmental factors in the wild species of rice
and their capacity for adaption to inclement growth conditions.