Effects of foliar application of inactivated yeast on the phenolic composition of Vitis vinifera L. cv. Agiorgitiko grapes under different irrigation levels

Figures & data

Figure 1 Grape growth (A) and juice composition (B) components at harvest.

Notes: Different letters within a parameter denote significant differences (Duncan’s test p≤0.05).

Abbreviations: BW, berry weight; C, control; IR, deficit irrigated; IR/SP, combined deficit irrigated and foliar sprayed; SP, foliar sprayed; SkW, skin weight; SeW, seed weight; °Be, Baumé degrees; TA, titratable acidity.

Table 1 Irrigation (I) and yeast application (Y) effects on grape growth components measured at harvest

Factors	Treatments	BW	SkW	SeW	°Be	TA	pH
I	Nonirrigated	1.57^b	0.355^b	0.089	12.3^b	4.92^a	3.63
	Irrigated	1.84^a	0.462^a	0.096	13.3^a	4.40^b	3.73
Y	Non-sprayed	1.72	0.425^a	0.093	13.0	4.56	3.70
	Sprayed	1.69	0.392^b	0.093	12.5	4.76	3.66
I×Y		ns	ns	ns	*	ns	ns

Notes: Statistically significant differences within a factor are indicated by different letters (p≤0.05);

* represents significance of the irrigation × yeast application (I×Y) interaction at p≤0.05.

Abbreviations: ns, not significant; BW, berry weight; SkW, skin weight; SeW, seed weight; °Be, Baumé degrees; TA, titratable acidity.

Table 2 Irrigation (I) and yeast application (Y) effects on phenolic potential of grapes

Factors	Treatments	Anthocyanins (mg/berry)	Anthocyanins (mg/berry g)	Total phenols (au/berry)	Total phenols (au/berry g)
I	Nonirrigated	1.25^b	0.83	1.87^b	1.25
	Irrigated	1.63^a	0.88	2.38^a	1.28
Y	Non-sprayed	1.63^a	0.91	2.36^a	1.32
	Sprayed	1.25^b	0.80	1.89^b	1.20
I×Y		ns	ns	***	ns

Notes: Statistically significant differences within a factor are indicated by different letters (p≤0.05);

*** represents significance of the irrigation × yeast application (I×Y) interaction at p≤0.001.

Abbreviations: ns, not significant; au, absorbance units.

Figure 2 Phenolic potential of grapes at harvest.

Notes: Different letters within a parameter denote significant differences (Duncan’s test p≤0.05).

Abbreviations: au, absorbance units; C, control; IR, deficit irrigated; IR/SP, combined deficit irrigated and foliar sprayed; SP, foliar sprayed.

Figure 3 Anthocyanin concentration (mg/g skin fresh weight) of Agiorgitiko grape skin at ripeness stage.

Notes: Different letters within a parameter denote significant differences (Duncan’s test p≤0.05).

Abbreviations: Dp, delphinidin-3-O-glucoside; Cn, cyanidin-3-O-glucoside; Pt, petunidin-3-O-glucoside; Pn, peonidin-3-O-glucoside; Mv, malvidin-3-O-glucoside; MvAc, malvidin 3-O-acetate-glucoside; MvCm, malvidin 3-O-coumarate-glucoside; TMA, total monomeric anthocyanins in mg of malvidin-3-O-glucoside/g of skins; TAE, total anthocyanin esters in mg of malvidin-3-O-glucoside/g of skins; C, control; IR, deficit irrigated; IR/SP, combined deficit irrigated and foliar sprayed; SP, foliar sprayed.

Table 3 Irrigation (I) and yeast application (Y) effects on anthocyanin concentration (mg/g skin fresh weight) of Agiorgitiko grape skin at ripeness stage

Factors	Treatments	Dp	Cn	Pt	Pn	Mv	MvAc	MvCm	TMA	TAE
I	Nonirrigated	0.050	0.035	0.060	0.062	0.631	0.059	0.344	0.838	0.403
	Irrigated	0.057	0.034	0.068	0.064	0.736	0.061	0.377	0.959	0.438
Y	Non-sprayed	0.049^b	0.034	0.061	0.057	0.684	0.059	0.361	0.884	0.420
	Sprayed	0.058^a	0.036	0.067	0.069	0.683	0.062	0.360	0.913	0.421
I×Y		ns	ns	ns	ns	ns	ns	ns	ns	ns

Note: Statistically significant differences within a factor are indicated by different letters (p≤0.05).

Abbreviations: ns, not significant; Dp, delphinidin-3-O-glucoside; Cn, cyanidin-3-O-glucoside; Pt, petunidin-3-O-glucoside; Pn, peonidin-3-O-glucoside; Mv, malvidin-3-O-glucoside; MvAc, malvidin 3-O-acetate-glucoside; MvCm, malvidin 3-O-coumarate-glucoside; TMA, total monomeric anthocyanins in mg of malvidin-3-O-glucoside/g of skins; TAE, total anthocyanin esters in mg of malvidin-3-O-glucoside/g of skins.

Table 4 Irrigation (I) and yeast application (Y) effects on phenolic composition of Agiorgitiko grape skin and seeds at harvest

Factors	Treatments	Skin			Seeds
		SkC	TSkP	SkAA	SeC	TSeP	SeAA
I	Nonirrigated	2.21^a	11.91	0.04	16.27	53.08	0.13
	Irrigated	1.55^b	11.04	0.04	17.64	54.75	0.15
Y	Non-sprayed	1.86	11.98	0.04	18.90	57.26	0.16
	Sprayed	1.90	10.98	0.04	15.01	50.57	0.13
I×Y		ns	ns	ns	ns	ns	ns

Note: Statistically significant differences within a factor are indicated by different letters (p≤0.05).

Abbreviations: ns, not significant; SkC, skin tannins in mg catechin/skin g; SeC, seed tannins in mg catechin/seed g; TSkP, total skin phenols in g of gallic acid/skin g; TSeP, total seed phenols in g of gallic acid/skin g; SkAA, skin antioxidant activity in mM trolox/skin g; SeAA, seed antioxidant activity in mM trolox/skin g.

Figure 4 Phenolic composition of Agiorgitiko grape skin and seed at harvest: skin and seed tannins and phenols (A) and skin and seed antioxidant activity (B).

Notes: Different letters within a parameter denote significant differences (Duncan’s test p≤0.05).

Abbreviations: SkC, skin tannins in mg catechin/skin g; TSkP, total skin phenols in g of gallic acid/skin g; SeC, seed tannins in mg catechin/seed g; TSeP, total seed phenols in g of gallic acid/skin g; SkAA, skin antioxidant activity in mM trolox/skin g; SeAA, seed antioxidant activity in mM trolox/skin g; C, control; IR, deficit irrigated; IR/SP, combined deficit irrigated and foliar sprayed; SP, foliar sprayed.

Table 5 Irrigation (I) and yeast application (Y) effects on alcohol content, TA, pH, and color properties of the produced wines

Factors	Treatments	Alcohol (% v/v)	TA (g/L)	pH	Color intensity	Color hue
I	Nonirrigated	12.2^b	5.4^a	3.63^b	8.46	0.66^b
	Irrigated	13.5^a	4.9^b	3.73^a	8.50	0.73^a
Y	Non-sprayed	12.9	5.1	3.68	8.63	0.70
	Sprayed	12.9	5.2	3.68	8.32	0.69
I×Y		ns	ns	ns	ns	ns

Note: Statistically significant differences within a factor are indicated by different letters (p≤0.05).

Abbreviations: ns, not significant; TA, titratable acidity.

Figure 5 Alcohol content (% v/v), TA (g/L), pH, and color properties of the produced wines.

Notes: Different letters within a parameter denote significant differences (Duncan’s test p≤0.05).

Abbreviations: TA, titratable acidity; C, control; IR, deficit irrigated; IR/SP, combined deficit irrigated and foliar sprayed; SP, foliar sprayed.

Table 6 Irrigation (I) and yeast application (Y) effects on anthocyanin concentration of the produced wines

Factors	Treatments	Dp	Cn	Pt	Pn	Mv	MvAc	MvCm	TMA	TAE
I	Nonirrigated	8.91	7.70	12.14	11.06	141.34	18.92	18.38	181.15	37.30
	Irrigated	9.26	7.65	14.60	12.80	205.86	24.91	26.17	250.17	51.08
Y	Non-sprayed	8.98	7.63	12.78	11.84	176.40	21.49	20.11	217.62	41.60
	Sprayed	9.19	7.72	13.97	12.01	170.81	22.34	24.44	213.70	46.78
I×Y		ns	ns	ns	ns	ns	ns	ns	ns	ns

Abbreviations: ns, not significant; Dp, delphinidin-3-O-glucoside; Cn, cyanidin-3-O-glucoside; Pt, petunidin-3-O-glucoside; Pn, peonidin-3-O-glucoside; Mv, malvidin-3-O-glucoside; MvAc, malvidin 3-O-acetate-glucoside; MvCm, malvidin 3-O-coumarate-glucoside; TMA, total monomeric anthocyanins in mg of malvidin-3-O-glucoside/g of skins; TAE, total anthocyanin esters in mg of malvidin-3-O-glucoside/g of skins.

Figure 6 Anthocyanin concentration of the produced wines.

Notes: Different letters within a parameter denote significant differences (Duncan’s test p≤0.05).

Abbreviations: Dp, delphinidin-3-O-glucoside; Cn, cyanidin-3-O-glucoside; Pt, petunidin-3-O-glucoside; Pn, peonidin-3-O-glucoside; Mv, malvidin-3-O-glucoside; MvAc, malvidin 3-O-acetate-glucoside; MvCm, malvidin 3-O-coumarate-glucoside; TMA, total monomeric anthocyanins in mg of malvidin-3-O-glucoside/g of skins; TAE, total anthocyanin esters in mg of malvidin-3-O-glucoside/g of skins; C, control; IR, deficit irrigated; IR/SP, combined deficit irrigated and foliar sprayed; SP, foliar sprayed.

Table 7 Irrigation (I) and yeast application (Y) effects on phenolic composition of the produced wines

Factors	Treatments	Anth	TC	TT	TP	OD280	AA
I	Nonirrigated	205	177	2.29	139	49.9	9.00
	Irrigated	266	177	2.36	180	52.0	8.73
Y	Non-sprayed	245	178	2.14	144	50.1	9.12
	Sprayed	226	176	2.51	175	51.7	8.61
I×Y		ns	ns	ns	ns	ns	**

Notes: **Represents significance of the irrigation × yeast application (I×Y) interaction at p≤0.01.

Abbreviations: ns, not significant; Anth, total anthocyanins in mg/L; TC, tannins in mg of catechin/L of wine; TT, total tannins in g/L of wine; TP, total phenols in mg of gallic acid/L of wine; OD280, total polyphenol index; AA, antioxidant activity in mM trolox/L of wine.

Figure 7 Phenolic composition of the produced wines.

Notes: Different letters within a parameter denote significant differences (Duncan’s test p≤0.05).

Abbreviations: Anth, total anthocyanins in mg/L; TC, tannins in mg of catechin/L of wine; TT, total tannins in g/L of wine; TP, total phenols in mg of gallic acid/L of wine; OD280, total polyphenol index; AA, antioxidant activity in mM trolox/L of wine; C, control; IR, deficit irrigated; IR/SP, combined deficit irrigated and foliar sprayed; SP, foliar sprayed.