Associations among the important characters measured in crosses of winter and spring wheat cultivars (triticum aestivum L. em thell)

The time, duration and rate of grain filling and physiological maturity were recognized as important in determining earliness and grain yield of wheats. High coefficients of determination for grain yield and whole plant dry weight also suggested possible high response of source to sink in crosses of winter and spring wheat cultivars. From the direct and indirect associations of grain yield, it would appear that a shorter duration of grain filling along with a shorter lag period from heading to anthesis are important for higher rates of grain filling if negative associations between earliness and grain yield are to be avoided.