fateme Hasanzadeh Naranjboni; reza ebrahimi; B. Moradi; T. Raiesi
Abstract
Introduction: Type and source of fertilizer in fruit trees nutrition play an important role in increasing yield and fruit quality, shelf-life prolonging and reducing waste in harvested fruit. Evaluation of the possibility of integrated use of organic and inorganic fertilizers or gradual replacement of ...
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Introduction: Type and source of fertilizer in fruit trees nutrition play an important role in increasing yield and fruit quality, shelf-life prolonging and reducing waste in harvested fruit. Evaluation of the possibility of integrated use of organic and inorganic fertilizers or gradual replacement of chemical fertilizers with organic manures is necessary in nutrition of kiwi vines, due to environmental issues resulted due to application of chemical fertilizers as well as increasing market value of organic fruits. Studies in this regard, especially comparison between organic manure and chemical fertilizer effects in kiwi fruit production is very limited. Therefore,this research was performed to investigate the short-term effects of four types of organic fertilizers as compared to chemical fertilizers over the amount of nutrients in leaves and fruits in Kiwi- Hayward variety.
Materials and Methods:This short-term field research was conducted in a randomized complete block design with six treatments including (azola, azocompost,vermicompost, cow manure, chemical fertilizer and control treatments) and four replications inHorticultural Science Research Institute, Citrus and Subtropical Fruits Research Center in Ramsar.Fertilizers were mixed with topsoil in canopy,weed control and drop irrigation was performed. The amount of nutrients, including nitrogen, phosphorus, potassium, calcium and magnesium in kiwi leaves and fruits were measured. In addition, relationship between nutrients in leaves and fruit yield was examined. The correlation analysis between mineral elements and the characteristics of qualitative and quantitative fruit firmness, dry matter, total soluble solids, titratable acidity and ratio of soluble solids to titratable acidity was performed. Stepwise regression equation between treatments with nitrogen, phosphorus, potassium and calcium was written on kiwifruit leaves and fruit. In addition, stepwise regression, the overall equation between yield and nutrient content of kiwifruit were reported.
Result and Discussion: The results showed that concentration of nitrogen, phosphorus, potassium, calcium and magnesium in leaves and fruits in Kiwi trees are higher than control treatment and the amounts of these elements in leaves and fruit werein optimum condition. Fertilization increased the amount of nitrogen, phosphorus, potassium, calcium and magnesium in leaves and fruit of kiwifruit trees in fertilizer treatments, compared to the control. Azocompost treatment had the highest amount of nitrogen and calcium in leaves and fruit compared to other treatments. Azocompost and vermicompost treatments had the highest potassium content in the leaf. As well as cow manure, vermicompost and Azocompost treatments resulted in the highest amount of potassium in fruit. Increasing theamount of nutrients in the leaves of kiwifruit had a direct impact. The correlation between the amount of elements in the leaves and fruit showed a direct and significant relationship between nitrogen, phosphorus and potassium leaves and nitrogen, phosphorus and potassium in fruits. Increasing of nutrients in kiwifruit leaves had a direct and positive impact on fruits. In stepwise regression equation there was a significant relationship between the yield andamounts of nitrogen, phosphorus and potassium and kiwi fruit trees, and by increasing of these elements and yield wasincreased. Correlation analysis between minerals and firmness in kiwifruit showed that there are negative correlations between the nitrogen content in mature fruit and firmness at harvest time at probability level 5 percent. In addition, positive and significant correlation between the calcium content in mature fruit and firmness, as well as between the percentage of dry matter and phosphorus and potassium contents of mature fruit at harvest time was obtained. Results showed that a significant negative correlation was between soluble solids with calcium and between titratable acidity with phosphorus, and of soluble solids ratio to titratable acidity with nitrogen and phosphorus the mature fruit at harvest mature fruit.
Conclusion: In general, according to these research results we can say that use of organic fertilizers like chemical fertilizers in kiwifriut orchards increasethenutrient amounts in leaves and fruit of kiwifruit. In addition,there was a significant positive correlation between quantitative and qualitative characteristics of kiwifruit and its leaf and fruit nutrients. Nitrogen, phosphorus and potassium have significant positive effect in increasing fruit yield.Chemical fertilizers leaching and environmental problems caused by the consumption of these fertilizers, motivated to useof organic fertilizers, such as vermicompost and azocompost in kiwifruit orchards, in order to produce fruit in north of the country.
amir ranjbar; H. Emami; Ali reza Karimi; R. Khorassani
Abstract
Introduction: Saffron is one of the most important economic plants in the Khorasan province. Awareness of soil quality in agricultural lands is essential for the best management of lands and for obtaining maximum economic benefit. In general, plant growth is a function of environmental factors especially ...
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Introduction: Saffron is one of the most important economic plants in the Khorasan province. Awareness of soil quality in agricultural lands is essential for the best management of lands and for obtaining maximum economic benefit. In general, plant growth is a function of environmental factors especially chemical and physical properties of soil (20). It has been demonstrated that there was a positive and high correlation between soil organic matter and saffron yield. Increasing the yield of saffron due to organic matter is probably due to soil nutrient, especially phosphorous and nitrogen and also improvement of soil physical quality (6, 28, 29). The yield of saffron in soils with high nitrogen as a result of vegetative growth is high (8). Shahandeh (6) found that most of the variation of saffron yield depends on soil properties. Due to the economic importance of saffron and the role of soil properties on saffron yield, this research was conducted to find the relationship between saffron yield and some soil physical and chemical properties, and to determine the contribution of soil properties that have the greatest impact on saffron yield in the Ghayenat area.
Materials and Methods: This research was performed in 30 saffron fields (30 soil samples) of the Ghayenat area (longitude 59° 10΄ 10.37˝ - 59° 11΄ 38.41˝ and latitude 33° 43΄ 35.08˝ - 33΄ 44΄ 02.78˝), which is located in the Khrasan province of Iran. In this research, 21 soil properties were regarded as the total data set (TDS). Then the principal component analysis (PCA) was used to determine the most important soil properties affecting saffron yield as a minimum data set (MDS) and the stepwise regression to estimate saffron yield. To estimate the yield of saffron in stepwise regression method, saffron yield was considered as a dependent variable and soil physical and chemical properties were considered to be independent variables.
Results and Discussion: According to the PCA method, among the 21 studied properties, 7 out of them including calcium, iron, zinc contents, sand, calcium carbonate equivalent percent, mean weight diameter of aggregates (MWD) and manganese (Mn) had the higher Eigenvalues. Therefore, the above properties were introduced as the most important soil properties in saffron fields. Calcium carbonate had the negative effect on the availability of micro-nutrients (26). Christensen et al. (15) found that by increasing the calcium carbonate in soil due to high pH and formation of insoluble components, the uptake of micro-nutrients is especially limited.
The results of stepwise regression method (equation 1) showed that soil acidity (pH), zinc content, bulk density, MWD, iron content, salinity (EC), organic carbon and available potassium in soil were the most important properties that affect the yield of saffron, so that the determination coefficient (R2) of the regression model was high (Table 2) and it can explain 74% of the variation of saffron yield.
Y = 6924.51 – 1187.31 pH – 89.65 EC + 71.6 Fe – 826.02 Zn + 471.55 OC, + 5490.96 K + 1353.56 BD + 752.82 MWD (1)
where Y: saffron yield (kgha-1), pH: soil acidity, EC: electoral conductivity (dSm-1), Fe: iron concentration (mgkg-1), Zn: zinc concentration (mgkg-1), OC: organic carbon (%), K: soil potassium (%), BD: soil bulk density (Mgm-3), and MWD: mean weight diameter of aggregates (MM).
Based on the absolute values of standard ß in the regression model (Table 3), pH value and then after Zn concentration had the most effect on saffron yield. In general, responses of different plants to soil pH is varied, and saffron grows satisfactory in pH = 7.8 (5). Soil pH influences the uptake of soil nutrients by plants (15), so that this parameter had the most effect on saffron yield and by increasing the soil pH, the yield of saffron decreases. According to the regression model, Zn concentration was the second parameter in saffron yield. Zn has the important role in structure of plant enzymes (30). After these 2 parameters, Bd, MWD, Fe concentration, EC, Organic carbon and K concentration in soil had more effect on saffron yield (Table 3).
Conclusion: According to both PCA and regression methods, the concentration of iron and zinc and MWD were determined as the important and effective soil properties on saffron yield in the Ghayenat area. In addition, soil pH in stepwise regression method and calcium carbonate in PCA method were determined as the effective properties on saffron yield. Therefore, it is suggested that the parameters of Zn, Fe, and MWD along with soil pH and calcium carbonate which were regarded individually in two methods, were considered as the most soil properties in saffron yield.
