Abstract:
Intercropping with filler crops can enhance space utilization, resource efficiency, and
yield stability in vegetable cultivation. In Sri Lanka, the standard okra spacing of 90
x 60 cm leaves gaps that can be used to grow filler crops like chili, improving land
use. This study evaluated the effects of chili filler planting and nutrient management
on the growth and yield of okra using a split-plot design with three replicates. Main
plot treatments included; (1) okra with chili (variety MI 02) as filler crop and (2) okra
without filler crops. Subplot treatments comprised; (1) recommended dosage of
inorganic fertilizer (RDIF) and (2) integrated nutrient management (50% RDIF +
50% compost). Key parameters measured included plant height, leaf count, SPAD
readings, length, weight, count, and diameter of pods. The okra yield was measured
based on the main plot area of 108 m², while the chili yield was measured based on
the subplot area of 54 m². Data was analyzed in SAS OnDemand for academics using
the PROC MIXED procedure, with means compared via Tukey’s test at a 0.05
significance level. Results indicated no significant yield differences (p>0.05)
between okra with (7.85±0.78 kg plot-1) and without (7±0.78 kg plot-1) filler planting.
Furthermore, the interaction effect was not significant. However, filler planting has
increased okra yield by 11% compared to okra without filler crop. The chili crop
produced an average yield of 287.6±142.24 g plot-1 with inorganic fertilizers and
222.16±55.60 g plot-1 with integrated nutrient management. Non-filler plots with
inorganic fertilizer achieved the highest dry biomass (1.01±0.082 kg) and pod
diameter (1.97±0.03 cm), while intercropped plots with inorganic fertilizer exhibited
the highest pod count (9±0.31). In conclusion, intercropping okra with chili optimizes
land use, increases yield, and promotes sustainable farming by maximizing resource
efficiency and productivity. This strategy maximizes yield and economic returns for
farmers.
