Abstract:
Mucuna bracteata is a legume with high biomass production and ability to cover the land
rapidly. It also identified as a potential cover crop for rubber plantations. However, its potential
of growing under coconut cultivation has not been investigated. Therefore, this study aimed to
assess the possibility of using Mucuna bracteata as a cover crop for coconut plantation in the low
country Intermediate Zone of Sri Lanka. A field experiment was carried out under 25 years old
adult coconut plantation on red yellow podzolic soil. Four treatments in this experiment were,
Mucuna bracteata planted in two rows in center of square {T1}, Mucuna bracteata planted in
three rows in center of square {T2}, Mucuna bracteata planted in four rows in center of square
{T3} and coconut without cover crop (control) {T4} and they were arranged in a Randomized
Complete Block design with four replicates. Soil properties were analyzed before and 75 days
after and ground cover were assessed 75 days after establishment. The highest ground coverage
of (81 %) and the lowest weed density were observed in coconut with Mucuna bracteata in
three rows. Mucuna bracteata planted plots had significantly (p < 0.05) lower bulk density (1.1 -
1.3 Mg / m3) than the control (1.5 Mg / m3) plots. Soil total nitrogen content of those treatments
(0.20 - 0.27 %) was also higher than the control (0.16 %) and there were no significant
difference between T2 and T3. According to the results of this study, it can be concluded that
Mucuna bracteata could be used as a cover crop under coconut in low country Intermediate
Zone of Sri Lanka. It also suggested that coconut with Mucuna bracteata planted in three rows
was the most suitable planting method for coconut cultivation which gave better ground cover,
lower soil bulk density and high soil nitrogen content than other treatments.
