The Effects of Divergent Selection for Root Capacitance in Maize

Root capacitance was divergently selected using a full sib recurrent selection scheme at 20% selection rate in Pool 16. Cycle bulks from four cycles were evaluated under drought stressed, N stressed and optimal conditions. Root capacitance increased with the high capacitance selection("strong root") at 1.29 nF cycle -1 and decreased with the low capacitance selection ("weak root") at -0.99 nF cycle -1 . Grain yield increased in both selections under stress conditions but increased in root and decreased in stalk under optimal conditions. Aboveground biomass increased in root at 0.35 t/ha cycle -1 and decreased in stalk at 0.25 t/ha -1 cycle -1 across environment. The anthesis silking interval decreased in both populations while leaf senescence decreased more in root. Thus, selection for high or low root capacitance may affect plant characteristics that are of importance under stress conditions.