اثر مقادیر و روش‌های مختلف کاربرد پوتریسین بر عمر گلجایی، برخی شاخص‌های فیزیولوژیکی و فعالیت آنزیمی میخک (Dianthus caryophyllus L.)

نوع مقاله : مقالات پژوهشی

نویسندگان

1 دانشگاه آزاد اسلامی واحد رشت

2 دانشگاه آزاد اسلامی رشت

3 دانشگاه آزاد اسلامی، واحد رشت

10.22067/jhs.2021.71518.1075

چکیده

میخک (Dianthus caryophyllus L.) یکی از مهم‌ترین گل‌های شاخه‌بریده‌ی جهان است که ارزش بالایی در صنعت گلکاری دارد. این گل فرازگرا به اتیلن و تنش آبی پس از برداشت بسیار حساس است و عمر گلجایی نسبتاً پایینی دارد. بیشتر اثرات منفی روی گل‌های شاخه‌بریده ناشی از تولید اتیلن است. استفاده از ترکیبات کاهنده یا ممانعت‌کننده‌ی سنتز اتیلن راهی مؤثر در افزایش عمر پس از برداشت میخک است. هدف از پژوهش حاضر، افزایش عمر گلجایی گل شاخه‌بریده‌ی میخک رقم "تمپو" با استفاده از مقادیر 01/0، 02/0 و 05/0 میلی‌‌مولار پوتریسین و روش‌های کاربرد پیوسته، پالس و اسپری بود. یک آزمایش بر پایه‌ی طرح کاملاً تصادفی با 10 تیمار در 3 تکرار و 150 شاخه گل انجام شد. در این پژوهش، صفات عمر گلجایی، درجه بریکس، جذب آب، کاهش وزن تر، درصد ماده خشک، کاروتنوئید گلبرگ، کلروفیل برگ، نشت یونی، آنزیم پراکسیداز، آنزیم سوپراکسیددیسموتاز و اتیلن اندازه‌گیری شدند. نتایج نشان داد که بیشترین عمر گلجایی (14 روز) در گل‌های شاخه‌بریده‌ی تیمارشده با 02/0 میلی‌مولار پوترسین به صورت اسپری (محلول‌پاشی) مشاهده شد. این تیمار همچنین باعث تولید کمترین اتیلن (36/2 نانولیتر در لیتر در ساعت در گرم وزن تر)، بیشترین جذب آب (88/1 میلی‌لیتر در هر گرم وزن تر) و بیشترین فعالیت آنزیم سوپراکسید دیسموتاز (04/23 واحد آنزیم در هر گرم وزن تر) گردید. برخی شاخص‌های فیزیولوژیک و فعالیت آنزیمی دیگر نیز مورد ارزیابی قرار گرفتند. در صفات عمر گلجایی، جذب آب، درجه‌ی بریکس، درصد ماده‌ی خشک، میزان کاروتنوئید و فعالیت آنزیم‌های پراکسیداز و سوپراکسیددیسموتاز، کمترین ارزش در گل‌های شاخه‌بریده‌ی شاهد ثبت شد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Effect of different concentrations and application methods of putrescine application on vase life, some physiological parameters and enzymatic activity of carnation (Dianthus caryophyllus L.) flowers

نویسندگان [English]

  • Davood Hashemabadi 1
  • Seyyed Abbas Razi 2
  • Behzad Kaviani 3
2 Islamic Azad University Rasht
3 Islamic Azad University, Rasht
چکیده [English]

Introduction: Carnation (Dianthus caryophyllus L.) is one of the most important cut flowers of the world. This flower is sensitive to postharvest ethylene and water stress and has short vase life. The use of retardants or inhibitors compounds of ethylene is an effective way to increase the postharvest life of carnation. Polyamines consist in putrescine (diamine), spermidine (triamine) and spermine (tetraamine) as new groups of plant growth regulators that are involved in various processes including increasing cell division, increasing enzyme biosynthesis, regulation of different developmental stages, differentiation, flowering, embryogenesis, rooting and maturity. These compounds exert their anti-aging properties by competing with ethylene production. Polyamines are low molecular weight organic compounds with aliphatic nitrogen groups that have different hydrocarbon rings and two or more amino groups (positive charge agents). These organic compounds bind to cell membranes, nucleic acids, and other macromolecules and are involved in chromatin formation, ion channel control, free radical neutralization, and gene expression. Cell membrane strength and stability play an important role in increasing the post-harvest life of horticultural crops. Putrescine is the major polyamine in plants, which is a precursor to the synthesis of spermidine and spermine, and its positive effect on increasing the vase life of some cut flowers has been reported. Vase life of cut flowers of chrysanthemum, rose and gladiolus was increased by application of putrescine. The purpose of the present research was to increase the vase life of cut carnation flower using different concentrations of putrescine and its application methods.

Materials and Methods: A factorial experiment based on completely randomized design with 10 treatments in 3 replicates, 30 plots and 150 cut flowers was performed to investigate the effect of different concentrations of putrescine (0.01, 0.02 and 0.05 mM) and its application methods (continuous, pulse and spray) on vase life of cut carnation (Dianthus caryophyllus L.) flowers. Some other traits such as water uptake, dry mater percentage, decrease of fresh weight, the content of leaf chlorophyll and sepal carotenoid, POD and SOD enzymes activity, MDA, decrease of °Brix (sucrose percentage in flower stalk, soluble sugar in stem end and sepal), ionic leakage, ethylene were also measured. The statistical analysis of data was performed using SAS. The least significant difference (LSD) test at P < 0.05 was used for comparisons of different means of various treatments.

Results and Discussion: Results showed that the maximum vase life was recorded in cut flowers treated with 0.02 mM putrescine as spray application. This treatment, also caused to the lowest ethylene production, the highest water uptake and the highest superoxide dismutase enzyme activity. Some physiological parameters and enzymatic activity were also evaluated. In most traits, minimum values were recorded in control cut flowers. Water stress, reduction of carbohydrates, ethylene production and the presence of microorganisms are the most important factors in reducing the vase life of cut flowers. Polyamines have anti-stress and anti-aging roles, which play these regulatory processes by strengthening the plasma membrane, inhibiting the activity of hydrolytic enzymes, and inhibiting ethylene synthesis. Polyamines also bind to cell wall pectin to protect them against destructive cell wall enzymes, including pectinase. Polyamines delay flower maturation by inhibiting the production of enzymes essential for the synthesis of ethylene and inhibit the activity of ethylene. Increasing polyamines by inhibiting lipid peroxidation is probably one of the mechanisms responsible for the anti-aging effect of polyamines. Polyamines have antioxidant properties and they reduce the number of oxygen free radicals and the permeability of plasma membranes by decreasing the activity of lipoxygenase, thereby increasing the vase life and quality of flowers. The use of polyamines to increase the vase life of some cut flowers has been reported, which the results of the present study are consistent with the results of these studies. Treatment of 20 mg l–1 spermine and 10 mg l–1 putrescine had the greatest effect on increasing vase life and reducing senescence of cut Alstroemeria flowers. Spermidine delayed the aging of carnation flowers. In cut rose cv. ‘Doles Vita’ flowers, the use of polyamines increased vase life. Treatment of 2 mM spermidine was the most suitable treatment to increase the vase life of cut carnation cv. ‘Red Corsa’ flowers. Cut rose flowers treated with humic acid and putrescine had the highest vase life compared to the control. Polyamines increased the vase life of cut gladiolus flowers by increasing the stability of plasma membranes. The addition of polyamines to the carnation flower preservative solution reduced their aging and prevented the production of ethylene. Polyamines appear to increase vase life in cut flowers by inhibiting ACC-synthase activity and reducing ethylene production. SOD, POD and catalase (CAT) enzymes, as antioxidant compounds, protect plants against reactive oxygen species and free radicals. Polyamines neutralize free radicals and are also involved in the synthesis of enzymes. Binding of polyamines to proteins protects them from the damaging effects of reactive oxygen species and free radicals. Treatment of 20 mg l–1 spermine increased the activity of SOD enzyme in cut Alstroemeria flowers. Concentrations of 10 and 20 mg l–1 putrescine and spermine significantly increased catalase activity. Spermidine treatment significantly increased the activity of free radical scavenging enzymes such as SOD and CAT. Putrescine in sunflower stimulated the catalase enzyme. At the first onset of senescence, antioxidant enzymes such as POD increase in petal cells to reduce the damaging effects of reactive oxygen species.

کلیدواژه‌ها [English]

  • Ethylene
  • Polyamine
  • Postharvest longevity
  • climacteric flower

مقالات آماده انتشار، پذیرفته شده
انتشار آنلاین از تاریخ 12 مهر 1400
  • تاریخ دریافت: 01 مرداد 1400
  • تاریخ بازنگری: 31 شهریور 1400
  • تاریخ پذیرش: 12 مهر 1400