Abstract:
The potential of verrnicompost, an organic biofertilizer made from earlhworm activity,
to improve soil fertility and crop productivity has drawn considerable interest. This
study investigates the effect of vermicompost on the growth and yield of different
cowpea varieties. (Vigna unguiculata). A pot experiment was conducted with varying
levels of vermicompost application, and its impact was compared to chemical
fertihzation methods. This experiment was laid out in Complete Randomized Design
(CRD) with replicates having the following treatments: T1 - Control (lkg soil alone),
T2- 25% vermicompost * 75'/o soil (2509 vermicompost i 7509 soil),T3- 50yo
vermicompost + 50% soil (5009 vermicompost + 5009 soil), T4- I5o/o vermicompost *
25% soil (7509 vermicompost + 2509 soil), T5- I00% vermicompost (1 kg
vermicompost alone) and T6- chemical fertlhzer.
Vermicompost application significantly improved growth and yield parameters of
cowpea varieties compared to the control and chemical treatment (p<0.05). The highest
plant height (50.94 + 3.00 cm by Bombay), number of leaves (39.00 r 1.22 by MI 35),
number of branches (14.20 + 1.48 by MI 35), number of nodes in main stem (20.00 +
2.45 by MI 35), Leaf arca index (19.26 + 14.91 cm2 by Bombay) were observed under
100% vermicompost. The lowest days to flowering (34.80 + 0.83 by Waruni and
Dawala), the lowest days to first mature pc,,,ls (47 .40 + 1.14 by Waruni), the longest
plant length (16.24 + 0.68 cm by ANKCP 2)., the highest number of seeds per pods
(11.00 + 1.58 by ANKCP 2), the highest number of pods per plant (4.40 ,L l.l4 by
Waruni),the highest seed length (0.72 +0.08 mm by Bombay), and highest dry pod
weight (2.60 + 0.10g by Bombay) were also recorded under I00% vermicompost,
showing significant differences from control and chemical applications.
There is a significant effect of fertilizer concentration and variety on plant height,
number of leaves, number of branches, number of nodes in main stem, leaf area index,
days to flowering, days to first mature pods, the plant length, seeds per pods, pods per
plant and seed length mainly affected by only fertilizer concentration. These findings
suggest that vermicompost can be a useful tool for improving the quality and yield of
different cowpea varieties in organic farming.