Abstract:
Leafy vegetables refer to the edible leaves of plants, which may be accompanied by tender petioles
and shoots. These vegetables are widely available across the world owing to their unique
characteristics. Among all leafy vegetables, the sessile weed (Alternanthera Sessillis), locally known
as Mukunuwanna is the most commonly consumed in Sri Lanka. Heavy use of agrochemicals is a
major problem with leafy vegetables because it poses serious health risk. Thus, it ought to be a top
priority to find out how to manage pests and diseases in leafy vegetables cultivation without using
chemicals. This experiment was conducted at the Agriculture Research Center, Thelijjawila during
2021 January to October to evaluate the curative effect of sprays of mancozeb (2 g/L), spent
mushroom substrate (1:3 w/v), cinnamon leaf extract (1:4 w/v) against Cercospora leaf spot and
white rust diseases in sessile weed. The experimental design was Randomized complete block
design(RCBD) with 3 replicates. Mukunuwanne variety “Pliyandala selection” was used in the
experiment. Disease severity percentage and yield (Mt/ha) were recorded. Disease severity
percentage was calculated using the ratio of number infected leaves to number of non-infected leaves
of randomly taken plants using 1×1 quadrat. Data were analyzed using STAR statistical software
package. Among the three treatments use of Mancozeb (2 g/L) found to be promising over other two
and compared the control as well. However, Cinnamon leaf extract (1:4 w/v) and spent mushroom
substrate (1:3 w/v) showed similar level of disease severity. The two diseases could be controlled at
a significant level with any of the tested treatments and also gave a yield advantage.
