Abstract:
Betel plant (Piper betle) leaves, harvested at
frequent intervals, result in the permanent
depletion of soil nutrients. Farmers often
complain that the amount of fertilizer
recommended by the Department of Export
Agriculture (DEA) is insufficient and there is a
tendency to overuse fertilizers. The study aimed to
assess the variability of soil fertility in betel
cultivations in the Kurunagala district. It
investigated the relationship between fertilizer
amounts and betel yield, along with relationship
of farm scale on soil fertility characteristics.
Thirty farmer fields were surveyed, measuring soil
fertility traits such as Nitrogen, Phosphorus,
Potassium, and soil pH. Of the selected fields,
84% betel poles were cultivated between 2 to 3
years, while 16% were less than 2 years old. The
survey found that 61% of farmers used cow dung
and 39% used green manure as organic fertilizer.
Harvesting was done every three weeks by 68% of
farmers and every two weeks by 32%. Chemical
fertilizers applied, biweekly by 72%, while the
remaining 28% did so every three weeks. All
farmers surveyed the used bed method and the
same chemical fertilizers mixture. The soil
analysis revealed that Wariyapola had the higher
nitrogen (2.48±0.8 mg/g), Phosphorus (0.13±0.01
mg/g), Potassium (0.06±0.01 mg/g) and soil pH
(5.63) values than Panduwasnuwara and
Bingiriya areas. There is a negative relationship
between amount of fertilizer applied and yield, but
the ratio of leaf length to leaf width had a positive
relationship. However, none of these differences
or relationship between farm scale and soil
fertility traits were statistically significant. The
results indicate that over-dosing with fertilizer
has no significant impact on betel yield
improvement, besides excessive use of chemical
fertilizers may increase cost and leads to nutrient
loss by leaching, runoff, and evaporation.
