Cocos nucifera coir-mediated green synthesis of Pd NPs and its investigation against larvae and agricultural pest

Figures & data

Figure 1. Experimental setup for larvicidal activity.

Figure 2. Adulticidal bioassay (anti-feedent method).

Figure 3. Collection of C. maculates egg for ovicidal activity.

Figure 4. UV–visible spectrum of Pd NPs at various intervals.

Figure 5. XRD pattern of Pd NPs.

Figure 6. FT-IR spectrum of Pd NPs.

Figure 7. TEM and particle size histogram of Pd NPs.

Figure 8. Zeta potential of Pd NPs.

Table 1. Larvicidal activity of synthesized Pd NPs against dengue vector A. aegypti.

			95% Confidencelimits (ppm)			95% Confidencelimits (ppm)
Concentration(ppm)	Mortality^a (%)	LC50 (ppm)	LCL	UCL	LC90 (ppm)	LCL	UCL	χ^2 value
100	12.8 ± 1.4	250.13	233.39	266.86	412.35	387.94	442.34	2.417
200	38.4 ± 1.2
300	62.8 ± 2.5
400	86.3 ± 2.6
500	98.6 ± 2.4

LC_50: lethal concentration brings out 50% Mortality and LC₉₀: lethal concentration brings out 90% mortality. LCL: lower confidence limit; UCL: upper confidence limit. Values in a column with a different superscript alphabet are significantly different at p < 0.05 (ANOVA; LD- Tukey’s Test). Values represent the mean ± SD of five replications.

^a Mortality of the larvae observed after 24 h of exposure period WHO (2005).

Table 2. Anti-feedent activity of Pd NPs and C. nucifera methanolic extract using C. Maculates.

	Anti-feedent activity (%)
Concentration(mg/L)	Pd NPs	C. nucifera coir methanolicextract
1.25	53.09 ± 0.28	54.6 ± 0.31
2.5	66.59 ± 0.24	68.47 ± 0.35
5	86.12 ± 0.32	86.12 ± 0.42
10	97.35 ± 0.27	91.98 ± 0.31
20	92.31 ± 0.31	99.01 ± 0.18

Anti-feedent activity assayed by the N/P-NPs with 0.5% DMSO with distilled water at different concentrations. Values in a column with a different superscript alphabet are significantly different at p < 0.05.

Table 3. (a) Ovicidal activity of Pd NPs.

	%Ovicidal activity concentrations tested (ppm)
Exposure (h)	1.25	2.5	5	10	20
24	65.84 ± 0.68	72.65 ± 0.41	74.22 ± 0.75	82.44 ± 0.41	92.84 ± 0.12
48	73.66 ± 0.58	77.39 ± 0.57	77.92 ± 0.22	85.93 ± 0.37	98.16 ± 0.14
72	92.11 ± 0.16	88.91 ± 0.40	93.91 ± 0.36	100.00 ± 0.00	100.00 ± 0.00
96	97.39 ± 0.10	98.54 ± 0.21	95.62 ± 0.31	100.00 ± 0.00	100.00 ± 0.00

Table 4. Oviposition deterrent activity using Pd NPs and C. nucifera coir methanolic extract against C. maculates.

	% Oviposition deterrent
Concentration(mg/L)	Pd NPs	C. nucifera coir methanolicextract
1.25	81.81 ± 0.66	83.63 ± 0.52
2.5	83.91 ± 0.43	91.48 ± 0.41
5	95.45 ± 0.55	97.52 ± 0.23
10	97.52 ± 0.21	100.0 ± 0.00
20	100.0 ± 0.00	100.0 ± 0.00

Values represent mean ± SD of five replications.