Effect of fertilizer application on tea plant productivity and phytochemicals in prepared black tea

Figures & data

Table 1. Fertilizer mixtures

Fertilizer mix	Application
Organic application (T1)	200 g vermicomposting per bush
Inorganic application (T2)	(urea 2.5 g + 5 g Di-ammonium phosphate (DAP) + 1 g Potash) per bush

Figure 1. The length of buds of different tea varieties under organic (T1) and inorganic treatments (T2).

* Bars sharing similar letters are not significantly different by LSD at p > 0.05

Figure 2. The breadth and weight of buds of different tea varieties under organic (T1) and inorganic treatments (T2).

* Bars sharing similar letters are not significantly different by LSD at p > 0.05

Table 2. T test for the physical properties of tea plant with organic and inorganic treatments

Tea varieties	Leaf specimens	Bud		1st leaf		2nd leaf
	Physical parameters	/t-value/	p-value	/t-value/	p-value	/t-value/	p-value
AV2	Weight (g)	5.883484	0.004171*	3.333974	0.044587*	23.2517	2.03E-05*
	Length (cm)	11.9182	0.00127*	2.288618	0.149311	106.75	1.81E-06*
	Breadth (cm)	2.65165	0.056884	8.812002	0.000915*	7.397576	0.005109*
PB-312	Weight (g)	4.52267	0.010637*	3.87298	0.017948*	21.9107	0.000208*
	Length (cm)	16.3565	0.000497*	19.4155	0.000298*	29.4553	7.91E-06*
	Breadth (cm)	2	0.139326	13.0052	0.00586*	8.10931	0.001257*
Takda 78	Weight (g)	5.753965	0.010429*	18.97857	4.54E-05*	11.555	0.00032*
	Length (cm)	15.411	0.000594*	10.95592	0.000394*	8.85438	0.000898*
	Breadth (cm)	8.12624	0.001247*	9.888666	0.000587*	6.14701	0.003552*
Bb-157	Weight (g)	4.54344	0.045185*	13.75	0.000162*	30.7439	7.56E-05*
	Length (cm)	1	0.391002	45.1668	2.39E-05*	19.9189	0.000277*
	Breadth (cm)	2.44949	0.070484	17.6392	6.07E-05*	17.6392	6.07E-05*
Gumti	Weight (g)	10	0.002128*	7.3413	0.001833*	56.0811	6.05E-07*
	Length (cm)	4.810702	0.040597*	8.140806	0.001239*	25.1029	0.000139*
	Breadth (cm)	1.73925	0.156975	6.25	0.003341*	8.75	0.00094*

*Significant at p < 0.05, E denotes the exponential

Figure 3. The length, breadth and weight of first leaf of different tea varieties under organic (T1) and inorganic treatments (T2).

* Bars sharing similar letters are not significantly different by LSD at p > 0.05

Figure 4. Caffeine (%) content of different varieties of (a) fresh leaves and (b) black tea under organic (T1) and inorganic treatments (T2).

* Bars sharing similar letters are not significantly different by LSD at p > 0.05. Alphabets “a-d” is used for fresh leaves while “m-p” is used for black tea.

Table 3. T test for the chemical properties of tea leaves and its black tea with organic and inorganic treatments

Variety	Parameters	/t-value/ between T1 and T2 for leaves	p-value	/t-value/ between T1 and T2 for black tea	p-value
Bb-157	Total Flavonoid content (mg QE/g dry extract)	7.16	0.00201*	44.18	1.6E-06*
	Total Polyphenols content (mg GAE/g dry extract)	62.98	3.81E-07*	41.57	3.1E-05*
	% DPPH inhibition)	11.79	0.0003*	18.10	0.00037*
	Caffeine (%)	0.069	0.947	3.595	0.036*
AV2	Total Flavonoid content (mg QE/g dry extract)	77.81	4.68E-06*	73.45	5.56E-06*
	Total Polyphenols content (mg GAE/g dry extract)	123.55	2.57E-08*	88.95	4.58E-08*
	% DPPH inhibition	5.64	0.01105*	3.34	0.044*
	Caffeine (%)	2.658	0.076	2.17	0.161
Takda 78	Total Flavonoid content (mg QE/g dry extract)	23.08	2.08E-05*	2.13	0.001 *
	Total Polyphenols content (mg GAE/g dry extract)	122.626	1.20E-06*	14.36	0.004*
	% DPPH inhibition	14.6	0.0007*	14.01	0.00015*
	Caffeine (%)	0.25	0.81	1.6	0.18
PB-312	Total Flavonoid content (mg QE/g dry extract)	50.05911	9.53E-07*	38.42	3.88E-05*
	Total Polyphenols content (mg GAE/g dry extract)	194.7434	4.17E-09*	161.58	8.8E-09*
	% DPPH inhibition	4.71407	0.01807*	2.78	0.049*
	Caffeine (%)	0.079	0.94	0.75	0.49
Gumti	Total Flavonoid content (mg QE/g dry extract)	39.04405	2.57E-06*	113.77	1.5E-06*
	Total Polyphenols content (mg GAE/g dry extract)	115.9107	1.42E-06*	111.4	3.89E-08*
	% DPPH inhibition	26.49	1.2E-05*	39.35	2.49E-06*
	Caffeine (%)	3.11	0.052	2.29	0.08

*Significant at p < 0.05, QE = Quercetin equivalent, GAE = Gallic acid equivalent, E denotes the exponential

Figure 5. TPC (mg GAE/g dry extract) of different varieties of (a) fresh leaves and (b) black tea under organic (T1) and inorganic treatments (T2).

* Bars sharing similar letters are not significantly different by LSD at p > 0.05. Alphabets “a-j” is used for fresh leaves while “m-r” is used for black tea.

Figure 6. TFC (mg QE/g dry extract) of different varieties of (a) fresh leaves and (b) black tea under organic (T1) and inorganic treatments (T2).

* Bars sharing similar letters are not significantly different by LSD at p > 0.05. Alphabets “a-h” is used for fresh leaves while “m-t” is used for black tea.

Figure 7. % DPPH scavenging activity of different varieties of (a) fresh leaves and (b) black tea under organic (T1) and inorganic treatments (T2).

* Bars sharing similar letters are not significantly different by LSD at p > 0.05. Alphabets “a-f” is used for fresh leaves while “m-s” is used for black tea.

Figure 8. Correlation plot between TFC, TPC, % DPPH scavenging activity, and caffeine content of black tea.

Figure 9. Bi-plot distributions of different samples with grouping TFC, TPC, % DPPH scavenging activity, and caffeine content (a) black tea under organic and inorganic treatments (b) black tea under organic treatment only. Here, A, B, G, P, and T denote AV2, Bb-157, Gumti, PB-312, and Takda 78, respectively, while T1 and T2 denote organic and inorganic, respectively.