Tab. 1:
Weather conditions of the Čačak region (Western Serbia) for 2023 and 2024*
| Months | Average monthly air temperature (°C) | Total precipitation (mm) | ||||
|---|---|---|---|---|---|---|
| 2023 | 2024 | LTA | 2023 | 2024 | LTA | |
| Jan | 3.4 | 2.0 | 0.03 | 90.0 | 56.0 | 44.1 |
| Feb | 3.3 | 9.0 | 2.3 | 37.2 | 7.8 | 38.9 |
| Mar | 7.5 | 10.0 | 6.8 | 65.0 | 49.6 | 46.2 |
| Apr | 11.7 | 13.9 | 11.5 | 6.6 | 48.2 | 51.6 |
| May | 16.2 | 15.9 | 16.8 | 20.0 | 92.4 | 72.7 |
| June | 19.4 | 22.1 | 20.0 | 140.8 | 61.4 | 87.3 |
| July | 23.1 | 24.8 | 21.5 | 88.0 | 58.8 | 79.1 |
| Aug | 21.9 | 25.3 | 21.2 | 49.6 | 18.4 | 58.0 |
| Sep | 19.5 | 18.0 | 16.7 | 75.2 | 86.0 | 56.2 |
| Oct | 15.1 | 12.9 | 11.4 | 11.8 | 37.0 | 51.1 |
| Nov | 7.1 | 4.7 | 6.0 | 134.6 | 66.8 | 55.9 |
| Dec | 5.5 | 2.5 | 1.4 | 30.2 | 66.8 | 50.4 |
| Mean or total | 12.8 | 13.4 | 11.3 | 749.0 | 649.2 | 690.2 |
* Source: Republic Hydro-meteorological Bureau in Belgrade, Serbia (http://www.hidmet.gov.rs) LTA: normal refers to the long-term average (45-year average, i.e. 1965–2010 period)
Fig. 1:
Typical symptomatic fruits on a PPV-M-infected apricot cultivar ‘Precoce de Thyrinte’ tree in Prislonica village near Čačak city, Serbia (photo taken in mid-June 2024 by T. Milošević).
Tab. 2:
Impact of Sharka disease on fruit weight of apricot fruits from PPV uninfected and PPV infected trees
| Source of variation | Fruit weight (g) |
|---|---|
| Viral status (A) | |
| PPV unifected | 43.20 ± 1.89 a |
| PPV infected | 33.42 ± 1.47 b |
| Year (B) | |
| 2023 | 39.44 ± 1.97 a |
| 2024 | 37.18 ± 1.39 b |
| ANOVA (F test) | |
| A | * |
| B | * |
| A×B | ns |
Tab. 3:
Soluble solids content, titratable acidity, pH juice, ripening index and ash content in fruits from PPV uninfected and PPV infected apricot trees
| Source of variation | Soluble solids content (°Brix) | Titratable acidity (%) | pH juice | Ripening index | Ash (%) | |
|---|---|---|---|---|---|---|
| Malic acid | Citric acid | |||||
| Viral status (A) | ||||||
| PPV unifected | 12.86 ± 0.06 a | 1.80 ± 0.01 b | 1.72 ± 0.01 b | 3.46 ± 0.01 a | 7.40 ± 0.04 a | 0.63 ± 0.01 b |
| PPV infected | 11.45 ± 0.03 b | 1.89 ± 0.01 a | 1.80 ± 0.01 a | 3.47 ± 0.01 a | 6.06 ± 0.04 b | 0.70 ± 0.00 a |
| Year (B) | ||||||
| 2023 | 12.66 ± 0.03 a | 1.68 ± 0.00 b | 1.61 ± 0.00 b | 3.50 ± 0.01 a | 7.67 ± 0.02 a | 0.72 ± 0.01 a |
| 2024 | 11.64 ± 0.06 b | 2.01 ± 0.01 a | 1.92 ± 0.01 a | 3.42 ± 0.01 b | 5.78 ± 0.06 b | 0.62 ± 0.00 b |
| ANOVA (F test) | ||||||
| A | * | * | * | ns | * | * |
| B | * | * | * | * | * | * |
| A×B | * | * | * | * | * | * |
Tab. 4:
Impact of Sharka disease on sugar contents and sweetness index in apricot fruits
| Source of variation | Invert sugars (%) | Reducing sugars (%) | Sucrose (%) | Total sugars (%) | Sweetness index |
|---|---|---|---|---|---|
| Viral status (A) | |||||
| PPV unifected | 7.99 ± 0.09 a | 1.81 ± 0.02 a | 7.59 ± 0.01 a | 9.80 ± 0.01 a | 5.60 ± 0.01 a |
| PPV infected | 7.62 ± 0.01 b | 0.81 ± 0.01 b | 7.24 ± 0.01 b | 8.46 ± 0.01 b | 4.50 ± 0.05 b |
| Year (B) | |||||
| 2023 | 7.92 ± 0.01 a | 1.10 ± 0.01 b | 7.53 ± 0.01 a | 9.02 ± 0.01 b | 5.49 ± 0.01 a |
| 2024 | 7.68 ± 0.02 b | 1.52 ± 0.01 a | 7.30 ± 0.01 b | 9.23 ± 0.02 a | 4.62 ± 0.05 b |
| ANOVA (F test) | |||||
| A | * | * | * | * | * |
| B | * | * | * | * | * |
| A×B | * | * | * | * | * |
Tab. 5:
Content of chlorophyll and total carotenoids in apricot fruit
| Source of variation | Chlorophyll a (μg 100 g‒1) | Chlorophyll b (μg 100 g‒1) | Total chlorophyll (a + b) (μg 100 g‒1) | Total carotenoids (μg 100 g‒1) |
|---|---|---|---|---|
| Viral status (A) | ||||
| PPV unifected | 172.88 ± 0.72 a | 78.04 ± 2.49 a | 250.92 ± 2.92 a | 939.49 ± 4.36 a |
| PPV infected | 92.53 ± 0.65 b | 68.11 ± 2.55 b | 160.64 ± 2.13 b | 775.03 ± 2.67 b |
| Year (B) | ||||
| 2023 | 166.97 ± 0.85 a | 35.00 ± 1.77 b | 201.97 ± 1.90 a | 846.17 ± 3.69 b |
| 2024 | 98.44 ± 0.52 b | 111.16 ± 3.26 a | 209.59 ± 3.15 a | 868.35 ± 3.34 a |
| ANOVA (F test) | ||||
| A | * | * | * | * |
| B | * | * | * | * |
| A×B | * | * | * | * |
Tab. 6:
Content of total phenolics and total flavonoids in apricot fruit and their antioxidant capacity
| Source of variation | Total phenolic content (mg 100 g‒1) | Total flavonoid content (mg 100 g‒1) | Total antioxidant capacity (mmol 100 g‒1) |
|---|---|---|---|
| Viral status (A) | |||
| PPV unifected | 26.19 ± 0.34 a | 7.24 ± 0.12 a | 0.35 ± 0.01 a |
| PPV infected | 22.13 ± 0.18 b | 4.93 ± 0.11 b | 0.35 ± 0.00 a |
| Year (B) | |||
| 2023 | 25.87 ± 0.25 a | 7.04 ± 0.11 a | 0.36 ± 0.01 a |
| 2024 | 22.46 ± 0.27 b | 5.12 ± 0.12 b | 0.34 ± 0.00 b |
| ANOVA (F test) | |||
| A | * | * | ns |
| B | * | * | * |
| A×B | * | * | * |