Effects of Time and Method of Pig Manure Application on Growth ...

PAT 2011;7 (1): 103 -116 ISSN: 0794-5213; Iren et al.,, <strong>Effects</strong> <strong>of</strong> <strong>Time</strong> <strong>and</strong> <strong>Method</strong> <strong>of</strong> <strong>Pig</strong> <strong>Manure</strong> <strong>Application</strong> .. 106
gives a plant population <strong>of</strong> 450 plants per bed (450/4.5 m 2 ) <strong>and</strong> 1,000,000 plants per
hectare. The plots were kept weed free throughout the cropping period by h<strong>and</strong> pulling
because <strong>of</strong> the closeness <strong>of</strong> the plants. Watering was done 2 times a day (morning <strong>and</strong>
evening) at the initial stage <strong>of</strong> development, <strong>and</strong> later reduced to once (evening only)
every day, due to good canopy development that shaded the ground <strong>and</strong> reduced soil
moisture loss.
Ten plants in each plot were r<strong>and</strong>omly selected <strong>and</strong> tagged. From the tagged
plant in each treatment plot, plant height, number <strong>of</strong> leaves per plant, fresh yield <strong>and</strong> dry
matter yield were measured. Plant height was measured with a meter rule as the height
from the base <strong>of</strong> the crop (ground level) to the tip <strong>of</strong> the plant, while the number <strong>of</strong>
leaves was taken to be the fully opened leaves per plant. These measurements
commenced 3 weeks after planting <strong>and</strong> continued at weekly interval until the end <strong>of</strong> the
experiment. Harvesting was done at 5 weeks after planting (5 WAP) by uprooting the
entire plant from an area <strong>of</strong> 100 cm x 100 cm at the centre <strong>of</strong> each plot. Fresh yield data
was taken at the time <strong>of</strong> harvest, where the weight <strong>of</strong> the uprooted plants were
determined plot by plot after rinsing the roots free <strong>of</strong> s<strong>and</strong>. For dry matter
determination, the ten tagged plants from each treatment plot were uprooted, rinsed, <strong>and</strong>
oven-dried at 65 0 C to constant weight (Maerere et al., 2001) <strong>and</strong> the weight
determined.
The data were subjected to analysis <strong>of</strong> variance (ANOVA) using the general
linear models (GLM) procedures <strong>of</strong> the Statistical Analysis Systems programme (SAS,
1989) to determine treatment effects. Treatment means, where significant, were
separated using Fisher’s Least Significant Difference (FLSD) at 0.05 probability level
(Wahua, 1999).
Results <strong>and</strong> discussion
Effect <strong>of</strong> time <strong>and</strong> method <strong>of</strong> pig manure application on Amaranthus height
The time <strong>of</strong> manure application independently affected Amaranthus height in
both years (Table 1) with the one week before planting (1WBP) time producing the
tallest plant at all stages <strong>of</strong> measurements (3 WAP, 4 WAP, 5 WAP), followed by the at
planting (AP) time <strong>of</strong> manure application, while the shortest plant was obtained from
the two weeks after planting (2 WAP) time <strong>of</strong> application. From the overall effect <strong>of</strong>
time <strong>of</strong> manure application on plant height in both years (Table 2), the highest plant
height <strong>of</strong> 17.79 cm at the growth stage <strong>of</strong> 3 WAP was obtained from the 1 WBP time <strong>of</strong>
application but it was not significantly different from the other times <strong>of</strong> application
except the 2 WAP time <strong>of</strong> manure application which had a mean height value <strong>of</strong> 14.10
cm. At the growth stage <strong>of</strong> 4 WAP, the tallest plant <strong>of</strong> 37.79 cm obtained with the
1WBP time <strong>of</strong> application was significantly (P< 0.05) higher than the heights obtained
from the other times <strong>of</strong> manure application except the AP time <strong>of</strong> application.The height