Abstract:
Six Pioneer corn hybrids were grown in
Kansas and four of the six hybrids within
three locations in Utah. The Utah hybrids
were harvested between the one-quarter and
one-half milk line stages of kernel maturity,
whereas the Kansas hybrids were harvested at
approximately 90% of kernel maturity.
Location had a significant effect on the
agronomic characteristics and chemical
composition of the hybrids. Whole-plant dry
matter (DM) and digestible DM yield, grain
yield, and percent grain were higher in the
Kansas-grown corn. The greater yield and
proportion of grain were results of the excellent
growth conditions i n 1992 and their advanced
stage of kernel maturity at harvest.
Experimental hybrid X0811 yielded the
highest whole-plant DM, grain, stover, and
digestible DM among the Kansas corns.
Hybrid X0811 also had the highest whole-plant
and stover in vitro DM digestibility
(IVDMD), the highest whole-plant and
stover crude protein (CP), and the lowest
whole-plant and stover neutral detergent fiber
(NDF) and acid detergent fiber (ADF)
contents among the Kansas corns. Hybrid
X0811 had the highest stover and digestible
DM yields, whole-plant C P and IVDMD, and
stover IVDMD and the lowest stover NDF
and ADF contents among the Utah hybrids.
The high digestible DM yields of hybrid
X0811 emphasize the contribution of the
stover fraction, in addition to the proportion
of grain, to the quality of the whole-plant
forage.