Influence of nitrogen application on dry biomass allocation and translocation in two maize varieties under short pre-anthesis and prolonged bracketing flowering periods of drought.

Plants have evolved different mechanisms to survive under stress conditions. This field study was conducted to evaluate the influence of nitrogen (N) application on dry biomass allocation and translocation in two maize varieties under short pre-anthesis and prolonged bracketing flowering period of drought. Two maize varieties, 'Pioneer 30B80ʹ and 'Suwan 4452ʹ receiving N at 0 (control), 160 (optimal) and 320 (supra-optimal) kg ha−1 were subjected to short pre-anthesis and prolonged bracketing flowering periods of drought. Prolonged bracketing flowering period of drought had more suppressive effect on anthesis-silking interval, dry matter allocation and translocation, leaf greenness, contribution of current assimilates to grain (CCAG), kernel number, kernel weight and kernel yield of two maize varieties than a short pre-anthesis drought. Nitrogen application at optimal level was the best for all traits, except CCAG. The maize variety 'Pioneer 30B80ʹ performed better under both drought types due to more root xylem vessels of large size and more accumulation of dry matter in leaves and roots than the variety 'Suwan 4452ʹ. Therefore, the variety 'Pioneer 30B80ʹ may be planted in drought prone environments and may be used in breeding program aimed at developing drought-tolerant cultivars. [ABSTRACT FROM AUTHOR]