Volumetric soil moisture content was monitored each year
with a portable soil moisture monitoring device known as
Diviner 2000, starting from 35 days after planting (DAP).
Details of the procedures were stated in Ref. [2].
Soil moisture data were recorded first on weekly basis and
later on daily basis when the impact of water stress became
very critical in each year. Data were downloaded from the
Diviner 2000 display unit on a desktop computer.
Data were also recorded on several physiological and
agronomic traits but only those of days to 50% silking (DTS),
plant height (PLHT), ear aspect (EASP), number of ears per
plant (EPP), and grain yield (GY) are presented in this report.
DTS was recorded as the number of days from planting to
when 50% of plants in a plot had emerged silks. PLHT was
measured in centimeters (cm) as the distance from the base of
the plant to the height of the first tassel branch. Ear aspect
(EASP) was visually rated on a scale of 1e5, where 1 ¼ clean,
uniform, large, and well-filled ears and 5 ¼ rotten, variable,
small, and partially filled ears. EPP was computed as the
proportion of total number of ears divided by the number of
plants harvested. All ears harvested from each plot were
shelled and weighed to determine grain weight and a representative
sample was taken to determine percent moisture.
Grain yield (GY), measured in kg ha1 adjusted to 15%
moisture content was calculated from grain weight and percent
moisture.