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Abstract Accumulation of heavy metal in agricultural land through traffic emission may result in soil contamination and elevated heavy metal uptake by crops, and thus affect food quality and safety. Therefore this study aims to : A -The first objective was to determine the effects of traffic pollution, dominantly presented by automobile on chemical composition, growth characters and yield of grapevine cv. flame seedless grown near the auto road . B -The second objective was to study the effect of humic acid, mono-calcium phosphate and mycorrhizal fungus on decrease the harmful effects of different levels of lead on the grape seedlings in two stages . The experimental works undertaken comprised two experiments which have been referred to as the ’Field Studies and ’Pot Studies. 1- Field Studies: It was conducted throughout two successive seasons of 2014 and 2015 on 6-year-old grapevine cv. Flame Seedless in a private vineyard located near the main road ( 5 m from roadside ) on Magaga region, el-Minya governorate, Egypt . The road, carrying more than 5.000 motor vehicles per day. Soil, grape leaves and fruits were sampled at a distance of 5, 50, 100 and 150 m from the roadside. This experiment investigate the effect of traffic pollution on chemical composition, growth characters and yield of Flame Seedless grapevines . 2- Pot Studies : A pot experiment was carried out during 2014 – 2015 seasons . In March 2014 stem cuttings cv. Flame Seedless were selected according to their uniformity in size (0.3 m height) and were transplanted to pots (4 kg soil capacity), Lead acetate at the rate of 0, 250, 500 and 1000 ppm were added in pots. After one week from addition of lead acetate the treatments were carried out using mono-calcium phosphate was added to the pot soil at the concentration ( 10g/kg soil ), humic acid was added to the pot soil at the concentration (4 g/ kg soil) and mycorrhizal fungus was added to the pot soil at the concentration ( 250 spores / kg soil ). In the end of growth season data of growth characteristics and chemical composition were recorded . In March,2015 Lead concentrations increased to ( 0,500,1000 and 2000 ppm ) and the previous treatments were replicated at the same concentrations . The previous determinations were analyzed . A- The results of Field Studies : 1- Effects of traffic pollution on vegetative growth parameters of grapevine : The results clearly indicate that all the growth parameters were suppressed gradually with the decrease in distances from roadside . Number of shoots/vine : Vines grown 5m from the roadside recorded the lowest number of shoots/vine (46.75 in the first season and 46.58 in the second season). Meanwhile, vines grown 150 m away from the roadside produced the highest number of shoots per vine (58.08 and 57.92 in both seasons , respectively). Shoot length: The highest values of shoot length (144.7 cm in the first season and 143.6 cm in the second season) were recorded for vines grown 150 m far from the motorway. The lowest significant values of shoot length (129.3 cm in the first season and 126.3 cm in the second season) were observed in vines grown closer to the roadside. Number of leaves per shoot : Vines grown 5m away from the roadside gave the lowest significant values which were 19.33 and 18.25 leaf / shoot in the first and second season, respectively. Vines grown 150 m from the roadside gave the highest significant values of 30.5 and 28.67 leaves per shoot in the first and the second respectively. Leaf area (cm2) : Leaf area for vines grown at distance of 5 m from the highway decreased by 12.43 % in the first season and by 11.38% in the second season comparing with leaf area of vines grown 150 m away from the roadside. Dry pruning weight (kg/vine) : The lowest significant in this respect were 1.46 and 1.32 kg/ vine for vines subjected to severe traffic pollution 5 m away from the roadside in the two successive seasons, respectively. 2. Effect of traffic pollution on yield parameters of grapevines: Number of clusters per vine : There has been a gradual increase in produced clusters per vine by growing far away from the roadside. Cluster weight : The heaviest cluster weight (497.5 in the 1st season and 485.0 g in the 2nd season) was recorded for vines grown 150 m away from the roadside. Vines grown 5 m from the road produced the smallest cluster (326.69 and 303.25 g ) in both seasons, respectively. Yield (kg/ vine): Yield of vines grown 5 m from the roadside decreased by 45.83 and 58.98 % compared to yield of vines grown at 150 m from the roadside in 2014 and 2015 seasons, respectively. 3- Effect of traffic pollution on fruit quality parameters of grapevines: Total soluble solids :In the first season, the highest value of TSS (18.09%) were recorded for vines grown 5 m away from the road followed by vines grown 50 m from the road then decreased up to 15.81% of berries grown 150 m from the roadside .The same trend was detected in the second season. Berry Acidity percentage (TA%) : The least berry acidity (0.53% in the 1st season and 0.51% in the 2nd season) was recorded for vines grown 5 m away from the road then it increased gradually to reach the maximum values in berries from vines grown 150 m from the roadside. 4. Effect of traffic pollution on lead content in vineyard soil, plant leaves and berries grapevines as affected by traffic pollution: Soil lead content : There were statistically significant differences between the distances in respect of the soil Pb concentration. Lead contents of the soil near to roadside (5- 50 m) were considerably higher than samples taken farther away from the road side (≥ 100 m) . Grape leaves lead content: Lead content in washed leaves of vines grown 150 m away from the roadside was 5.44 and 6.27 ppm during the 1st and the 2nd season, respectively, while the Pb content of washed leaves of vines grown 5 m from the road were 10.03, 12.02 ppm during the 1st and the 2nd season, respectively. Berry lead content: The obtained results revealed that vines grown at the distance of 150 m from the motorway gave the lowest significant values (4.21 and 4.23 ppm) followed by berries of vines grown 100 m from the highway (8.54 and 8.66 ) ppm in the first and second seasons, respectively. 5- Effect of traffic pollution on leaf biochemical parameters of grapevine : Total carbohydrates: The highest significant values were 17.14% in 2014 and 16.96% in 2015 for vines grown 150 m from the roadside. Also, the lowest significant values(16.35% in the first season and 16.29% in the second season ) were observed in vines grown 5 m away from the road. Total protein: The average total protein values were 8.07, 8.29, 8.55 and 8.78 g/100g dry weight for vines grown at 5, 50, 100, and 150 m apart from the roadside, respectively in the first season, while they were 7.80, 8.05, 8.25 and 8.40 g/100g dry weight in the second season, respectively. Free proline : The highest significant values of free proline were 78.50 mg/100g in first season and 80.32 mg/100g in the second season for vines grown 5 m away from the roadside. While, vines grown 150 m apart from the road recorded the lowest significant values in this respect. 6- Effect of traffic pollution on leaf NPK content of grapevines : In general values of some nutrients (nitrogen, phosphors and potassium) increased significantly by increased the distance from roadside. 7- Effect of traffic pollution on membrane stability index (MSI%) and chlorophyll fluorescence of grapevines: Membrane Stability Index ( MSI % ) :Vines grown at 5m apart from the roadside had the lowest significant value of MSI (46.73% in the first season and 45.72 %in the second season). Chlorophyll Fluorescence : It could be noticed that traffic pollution resulted in a negative effect on photosynthesis. 8 - Effect of traffic pollution on the average rate of dust fall on grapevine leaves : It can be seen that the average of weight of grape leaf dust tend to decreased as we move away from road and increased in samples near the road. B –The Results of Pot Experiment : 1-Effects of Humic acid (HA), Mono Calcium Phosphate (MCP) and Mycorrhizae fungi (AM) on vegetative growth of grape seedlings grown in lead- polluted soil : Plant height: Incorporating any of soil remediation agents i.e humic acid, mono calcium phosphate or mycorrhizae fungi had a positive effect on plant height of grape seedlings grown in lead- polluted soil compared with untreated plants. Leaves number per plant : Under the same level of soil pollution, addition of any of soil remediation agents significantly increased number of leaves per plant when compared to non remediated plants and no significant differences were recorded between humic acid, mono calcium phosphate or mycorrhizae in terms of their effects on number of produced leaves. Leaf area (cm2 ) : Addition of soil remediation agents, humic acid, mono calcium phosphate or mycorrhizae fungi had an increase effect on leaf area of grape seedlings grown in leadpolluted soil compared with untreated plants. Plant dry weight (g) : There is a positive effects of addition of Humic acid (HA), Mono Calcium Phosphate (MCP) and Mycorrhizae fungi (AM) to lead polluted soil on plant dry weight (g) compared with untreated plants. 2-Effects of Humic acid (HA), Mono Calcium Phosphate (MCP) and Mycorrhizae fungi (AM) on leaf lead content of grape seedlings grown in lead- polluted soil: In the first season, at the lead soil pollution rate of 250 ppm, results showed that concentration of Pb in grape seedling leaves was reduced by 25, 21.63 and 20.25 % due to application of mono-calcium phosphate, humic acid and Mycorrhizae fungi, respectively compared to control. While at the Pb soil pollution rate of 1000 ppm, results showed that concentration of Pb in grape seedling leaves was reduced by 29.49, 23.36 and 22.25 % due to application of mono-calcium phosphate, humic acid and Mycorrhizae fungi, respectively compared to the non remediated control. This trend was detected in the second season. It is clear that contents of leaf lead (Pb) was lowered by phosphate treatment than in those from other treatments. 3. Effects of Humic acid (HA), Mono Calcium Phosphate (MCP) and Mycorrhizae fungi (AM) on leaf biochemical composition of grape seedlings grown in lead- polluted soil: Total carbohydrates : Under the same level of soil pollution, addition of humic acid or mycorrhizae significantly increased leaf carbohydrates when compared to non remediated plants. Mono calcium phosphate tends to improve leaf carbohydrates content more than humic acid or mycorrhizae. Leaf total protein (% ) : Soil addition of any soil remediation agents i.e humic acid, mono calcium phosphate or mycorrhizae increased leaf protein content of grape seedlings grown in lead- polluted soil compared with untreated plants. Their soil application significantly increased leaf protein content of seedlings grown in lead- polluted soil at any of the tested Pb concentrations compared to the non remediated treatments. Leaf proline content (mg/ 100 g) : Marked reductions in proline concentrations were achieved by mono-calcium phosphate treatment followed by humic acid and mycorrhizae fungi treatments. The findings showed that treated with monocalcium phosphate show less stress indices under soil Pb pollution. 4- Effects of Humic acid (HA), Mono Calcium Phosphate(MCP) and Mycorrhizae fungi (AM) on chlorophyll fluorescence and membrane stability index (MSI) of grape seedlings grown in lead- polluted soil : The results show that the mono calcium phosphate, humic acid, and mycorrhizae fungi remediation agents were found to increase the percents of chlorophyll fluorescence and MSI when compared to plants grown in un-remediated contaminated soil under all levels of lead pollution . Its clearly that the application of mono-calcium phosphate ( 10 g / kg soil) , humic acid ( 4g/kg soil ) and mycorrhizae fungi ( 250 spores/ kg soil ) treatments can be applied for reducing leaf lead content and increasing the growth of grape seedlings . It is clearly that contents of leaf lead was lower by phosphate treatment than in those from other treatments . Such strategies may help ameliorate the pollution of on soil by heavy metals . |