Nitrate reductase activity in two corn cultivars as affected by nitrate-nitrogen fertilization and water stress
1985
Nicor, H.C.
Seeds of UPCA Var 1 and Across 8075 were planted to sandy soil contained in clay pots. The plants were fertilized with nitrate-nitrogen equivalent to 0, 30, 60 and 90 ppm added to modified Hoaglands' solution. Drought was imposed by withholding water for a period of 10 days starting from 15 days after emergence. NRA [nitrogen reductase activity], RWC [relative water content], tissue nitrate, free poline, stomatal aperture, resistance, and density were determined every other day and at 24 hours after rewatering. Their effects under the conditions prevailing in the present study were shown to be transient and readily reversible upon rewatering. Stomatal responses to rehydration was rather slow because the control levels of the size of the aperture and resistance were far from being regained
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