نوع مقاله : مقالات پژوهشی
نویسندگان
دانشگاه ولی عصر (عج) رفسنجان
چکیده
خاک‌های ایران عمدتاً آهکی هستند که در آن‌ها کمبود عناصر کممصرف از جمله منگنز به دلیل pH بالا و تثبیت عناصر غذایی مشاهده می‌شود. هدف این مطالعه بررسی اثر منگنز بر رشد و ترکیب شیمیایی نهال‌های پسته در تعدادی از خاک‌های آهکی با خصوصیات فیزیکی و شیمیایی متفاوت بود. برای این منظور یک آزمایش گلخانه‌ای به صورت فاکتوریل در قالب طرح کاملاً تصادفی با سه تکرار انجام شد. تیمارها شامل سه سطح منگنز (0، 10 و 20 میلی‌گرم منگنز در کیلوگرم خاک به صورت سولفات منگنز) و 12 نوع خاک متفاوت از منطقه‌ی رفسنجان در جنوب ایران بود. نتایج نشان داد که کاربرد 10 میلی‌گرم منگنز در کیلوگرم خاک باعث افزایش برخی پارامترهای رشدی گردید. ترکیب شیمیایی (غلظت و جذب) اندام هوایی نهال‌های پسته هم تحت تأثیر کاربرد منگنز قرار گرفت. کاربرد منگنز غلظت و جذب آهن، غلظت روی و مس را در اندام هوایی نهال پسته کاهش داد بهطوریکه بالاترین غلظت این عناصر در تیمار شاهد مشاهده شد. کاهش غلظت عناصر مس و روی در تیمار 10 میلی‌گرم منگنز در کیلوگرم خاک از لحاظ آماری معنی‌دار نبود ولی در تیمار 20 میلی‌گرم در کیلوگرم معنی‌دار شد.
کلیدواژه‌ها
عنوان مقاله [English]
Growth and Chemical Composition of Pistachio Seedlings under Different Levels of Manganese in Greenhouse Conditions
نویسندگان [English]
- T. Poorbafrani
- A. Tajabadi Pour
- V. Mozafari
- A.R. Akhgar
Vali-e-Asr University of Rafsanjan
چکیده [English]
Introduction: Pistachio is one of the most important crops in many regions of Iran with respect of production and export. There are more than 470000 ha of nonbearing and bearing pistachio trees mainly in Kerman province. Despite the economic importance of this crop, very little information is available on its nutritional requirements. Pistachio trees like other crops need to macro and micro nutrients. one of these elements is manganese (Mn). Manganese is an essential mineral nutrient, playing a key role in several physiological processes, particularly photosynthesis, respiration and nitrogen assimilation. This element is normally supplied to the plants by soil. Therefore, soil conditions affect its availability to plants. Soils with high pH, calcareous soils, especially those with poor drainage and high organic matter, are among the soils which produce Mn-deficient plants. Calcium carbonate is the major inactivation factor of Mn in calcareous soils. The soils of Iran are predominantly calcareous in which micronutrients deficiency, including Mn, is observed due to the high pH and nutrient fixation. The objective of this research was to examine the effect of manganese application on growth and chemical composition of pistachio seedlings in some calcareous soils with different chemical and physical properties.
Materials and Methods: For this purpose a greenhouse experiment was carried out as factorial (two factors including soil type and Mn levels) experiment in completely randomized design with three replications. Treatments were consisted of three levels of Mn (0, 10 and 20 mg Mn Kg-1 soil as Manganese sulfate) and 12 different soils from Rafsanjan region in Southern Iran. Soil samples were air dried and crushed to pass through a 2-mm sieve, and some physical and chemical properties of soils such as texture, electrical conductivity, pH, organic matter content, calcium carbonate equivalent, cation exchange capacity and iron, manganese, copper and zinc availability were determined. Then plastic pots were filled with 5 kg of these soils. Pistachio seeds (cv Badami Zarand) were placed in muslin sacks and pretreated for 24 h with Benomyl solution. The germinated seeds were planted in each pot, and each pot was irrigated with distilled water. Nitrogen and phosphorous were applied uniformly to all pots at the rate of 50 mg kg−1 soil as ammonium nitrate and potassium dihydrogen phosphate forms, respectively. Zinc, iron and copper also were added to treatments at level of 5 mg kg−1 soil as zinc sulfate, iron sequestrine138 and copper sulfate. After 24 weeks, the seedlings were cut at the soil surface, and the roots were washed free of soil. Leaves, stems and roots were dried at 70 oC for 48 h in an oven. The total leaf, stem, and root dry weights were recorded. The ground plant samples were dry- ashed at 550oC, dissolved in 2 N HCl, and made to volume with hot distilled water. Plant Mn, Cu, Zn and Fe concentrations determined by atomic absorption spectrophotometry. All data were statistically analyzed according to the technique of analysis variance (ANOVA) by MSTATC.
Results and Discussion: Results indicated that the application of manganese increased leaf, stem and root dry weight of pistachio seedlings so that the maximum amount of the dry weight of roots stems and leaves of pistachio seedlings were observed at 10 mg Mn kg-1soil. Application of 10 mg Mn kg-1 soil increased leaf, stem and root dry weight by 19.2%, 25.2% and 23.9% in comparison to control, respectively. Chemical composition (concentration and uptake) of shoot of pistachio seedlings was also affected by Mn application. Mn application decreased the concentration and uptake of iron, concentrations of copper and zinc in Pistachio seedling shoots so that the highest concentrations of these elements were observed in control treatment. Reductions in concentrations of zinc and copper elements in 10 mg Mn kg-1 treatment were not statistically significant but in 20 mg Mn kg-1 treatment they were significant.
Conclusions: The results of this research showed that the application of 10 mg Mn kg-1soilto highly calcareous soils significantly increased most of growth parameters of pistachio seedlings in comparison to control. Although higher amounts of manganese (20 mg Mn kg-1 soil) reduced the growth parameters than the previous level. In overall, the results of this study indicated that for optimum growth and chemical composition of pistachio seedlings in calcareous soils, application of 10 mg Mn kg-1 sol is necessary.
کلیدواژه‌ها [English]
- Calcareous soils
- chemical composition
- Manganese
- Pistachio
)
ارسال نظر در مورد این مقاله