Most of the yield of wheat is contributed by the main shoot and a few tillers. We hypothesize that a wheat plant with two to three tillers and restricted growth of unproductive tillers will maximize grain yield. The tin mutant wheat is ideal for modulating tillering and identifying the optimal tiller number. Tiller inhibition in tin is associated with precocious stem internode elongation. Internodes in tin start to elongate immediately after the transition of the shoot apex from vegetative to flowering phase. Internode elongation indirectly reduces tillering by limiting supply of sugars to tiller buds. By modulating flowering time, thus the timing of internode elongation in tin, the number of productive tillers could be specified and the yield per shoot and per plant could be analyzed. Besides precocious internode elongation, the tin tends to stunt in long days and lower temperatures. Identifying the molecular basis of precocious internode elongation and stunting will be useful for improving tillering and yield of wheat. Therefore, this project has the following two objectives: a) modulating timing of internode elongation in tin indirectly by inducing flowering at different times and investigating its effect on tiller number and yield. b) Transcriptome analysis to identify molecular mechanisms controlling precocious internode elongation and stunting in tin.