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International Journal of Horticulture 2014, Vol.4, No.14, 1
-
10
http://ijh.biopublisher.ca
9
Table 5 Growth and yield characters of pepper grown as affected by planting date (supplementary and full irrigation), and weekly and
fortnight irrigation regimes
Treatments
Root
length
(cm)
Root dry weight
(g)
Shoot dry weight
(g)
Leaf area
(cm
2
)
50% flowering
(days)
Fruit yield
(t/ha)
Harvest index
Sowing dates
December
17.7
23.0
127.4
4.3
75
8.8
0.53
January
18.6
71.0
147.0
6.2
70
8.3
0.52
LSD (0.05)
3.1
5.2
9.3
1.6
4.1
1.8
ns
Irrigation regimes
Weekly
17.1
45.5
141.4
5.6
75
9.0
0.54
Fortnightly
19.2
49.0
133.0
5.0
71
8.1
0.51
LSD(0.05)
2.4
2.5
5.8
0.6
2.4
2.3
ns
Sowing date x Irrigation regime
LSD (0.05)
*
*
*
*
ns
*
ns
Note: *(significant: P > 0.05), ns (not significant: P > 0.05)
Effects of irrigation interval
Irrigation regime affected shoot biomass and fruit
yield, In addition to higher roots and shoot dry
weights, leaf area and fruit yield were higher in
weekly irrigation (Table 5). Across the sowing dates
(December and January), fruit yields were lower under
fortnight irrigation (averaging 8.1 t ha
-1
) compared to
weekly (averaging 9 t ha
-1
) interval. About 6.4 and
8.2 % yield reductions were obtained under fortnight
compared with weekly irrigation. Irrigation regimes
(weekly and fortnight intervals) affected soil moisture
storage. The increases in yield under weekly irrigation
is attributable to improvements in fruit yield
components like number and weight of fruits per plant
and mean fruit weight (g.plant
-1
), these fruit yield
components were lower under fortnight irrigation.
Weekly irrigation provided more frequent replenishment
of depleted moisture from crop root zone, this might
have promoted uptake and use of moisture required
for fruit initiation and filling. Although, low to mild
moisture stress was obtained during establishment and
mid-season (1 – 7 WAT), imposition of weekly and
fortnight irrigation during the reproductive growth
was successful at alleviating greater soil moisture
deficit stress and sustained fruit yield. Irrigation
interval intervals, soil moisture depletion over two
sampling periods were summed to determine seasonal
water use by pepper and the results were presented in
Table 3 and 4. The results showed that application of
between 60 and 40 mm (41.4 and 20.7 litres) for the
weekly and fortnight irrigation intervals produced
seasonal moisture contents of 201 mm within crop
root zone was 164 mm. Although, the dry irrigation
treatment (fortnight interval) brought about yield
reductions however, about 24 % water savings
(reduced crop evapotranspiration) were obtained
under fortnight compared with weekly irrigation (60
mm). Water productivity values were 1.85 and 1.25
kg/ha/mm for the December and January sowings.
Planting date by irrigation interval interaction
The interaction of sowing date by irrigation interval is
significant on some growth and fruit yield characters
of pepper measured in this study (Table 5). This is an
indication that the two sets of treatments were
interdependence on pepper. The results of this study
demonstrated that irrigation regimes imposed
(fortnight and weekly) produced differences in water
use and fruit yields and the effects of irrigation will be
dependent on local weather conditions and crop
rooting characteristics such as rooting depth and
density. As sowing was delayed from December to
January, stressful growing environmental conditions
elicited by increasing intensities of soil moisture and
vapour pressure deficits and high air temperatures
could have lead to reductions in fruit yields across the
irrigation treatments. It is concluded that as
precipitation reduces over time especially during crop
growing seasons, the development of water-saving
management practices for sustainable agriculture now
and in the future is imperative.
Conclusion
The results of the field study conducted on sandy loam
Alfisol in an inland valley swamp (flood plain)