Antifungal activity of biosynthesised copper nanoparticles evaluated against red root-rot disease in tea plants

Figures & data

Figure 1. Absorbance at 590 nm for copper nanoparticles synthesised by Streptomyces griseus cells. (a) Sample and (b) control.

Figure 2. TEM images of copper nanoparticles synthesised by S. gresius at various magnifications. TEM images of copper nanoparticles at various magnifications and different nanosize distribution (a–d).

Figure 3. Biosynthesised copper nanoparticle size distribution.

Figure 4. XRD pattern of biosynthesised copper nanoparticles.

Figure 5. Fourier transform infrared spectroscopy analysis of copper nanoparticles.

Table. 1. Edaphic parameters of P. hypolateritia infested tea soil in response to bulk and nano copper during 2011–2014.

	Bulk Cu				Nano Cu				Control
Edaphic parameters	3	6	9	12	3	6	9	12	3	6	9	12	SE±	CD at P = 0.05
pH	4.8	4.6	4.6	5.1	4.7	4.5	5.0	5.3	4.5	4.7	4.9	5.0	.067	0.00
EC (ds/m)	0.18	0.16	0.20	0.19	0.17	0.21	0.19	0.23	0.15	0.17	0.16	0.17	.005	0.00
WHC	31.7	35.3	27.0	23.3	27.7	24.0	33.5	29.7	32.0	28.3	25.7	29.5	1.13	0.02
OC	2.9	3.2	3.0	2.6	2.7	3.5	3.0	2.9	3.3	2.9	3.1	2.7	.15	0.01
N	2.6	3.0	2.8	2.5	2.7	3.1	3.6	2.9	2.4	2.9	2.6	2.3	.132	0.00
P	13.9	15.7	16.2	14.8	13.1	15.5	17.3	16.4	15.3	14.8	14.2	13.3	.327	0.00
K	63.0	58.3	53.0	49.5	56.0	64.5	71.3	68.0	57.3	61.5	52.0	46.5	1.71	0.01
Ca	158.4	246.0	191.2	174.5	161.9	234.3	196.7	192.0	165.4	251.0	210.7	182.5	11.19	0.03
Mg	86.1	99.4	122.7	114.9	121.4	97.8	117.0	88.3	111.2	92.5	125.4	83.6	3.44	0.02
Na	26.5	32.9	25.0	22.7	23.8	30.9	27.4	25.6	21.9	33.8	29.0	24.7	.81	0.00

Table 2. Effect of fungicide, bulk and nanocopper on red root-rot disease incidence and leaf yield during 2011–2014.

		Disease incidence (%)
T. No.	Treatments	Pre-treatment	Post-treatment*	Disease reduction (%)	Yield (kg ha^−^1 made tea)
T1	Carbendazim – 0.05%	40.9^a	17.5^f	57.2^a	3256^b
T2	Bulk copper	38.6^a	21.1^d	45.3^c	3177^c
T3	Nanocopper – 1 ppm	37.4^a	30.0^b	19.7^f	2981^e
T4	Nanocopper – 1.5 ppm	36.3^a	26.4^c	27.2^e	3027^d
T5	Nanocopper – 2.0 ppm	39.7^a	22.3^d	43.8^d	3143^c
T6	Nanocopper – 2.5 ppm	38.1^a	18.0^e	52.7^b	3565^a
T7	Infected control	40.5^a	51.7^a	−27.6^g	2734^f
	SE ±	0.37	1.17	2.65	36.3
	CD @ P = 0.05	0.68	0.00	0.00	0.00

Note: Mean values in each column followed by different letters are significantly different at P = 0.05, according to DMRT.

Figure 6. Total population of bacteria, fungi and actinomycetes in copper nanoparticles applied to tea soil.