ارزیابی اثر غلظت‌های مختلف و روش کاربرد یونیکونازول و سایکوسل بر رشد رویشی و خصوصیات بیوشیمیایی دورگ لیلیوم (longiflorum×asiatic cv. eyeliner)

پژوهش حاضر به منظور ارزیابی اثر کندکننده های رشد و روش کاربرد آن ها در تولید گیاه پاکوتاه لیلیوم (رقم آیلاینر) انجام گرفت. آزمایش به صورت فاکتوریل در قالب طرح کاملاَ تصادفی با دو فاکتور شامل استفاده از کندکننده های رشد (سایکوسل؛ صفر، 1000 و 1500 میلی گرم در لیتر) و یونیکونازول؛ صفر، 5 و 10 میلی گرم در لیتر) و نحوه کاربرد این مواد (محلول پاشی برگ و غوطه وری سوخ) انجام شد. با توجه به نتایج به دست آمده اثر تیمارها و نحوه کاربرد آن ها بر بیشتر صفات مورد بررسی معنی دار بود، به طوریکه کمترین ارتفاع ساقه با 67 درصد کاهش نسبت به شاهد، در تیمار محلول پاشی یونیکونازول با غلظت 10 میلی گرم در لیتر به دست آمد. همچنین بیشترین کلروفیل کل در همین تیمار به روش غوطه وری ثبت شد. کوتاه‌ترین زمان تشکیل غنچه در تیمار سایکوسل با غلظت 1500 میلی‌گرم در لیتر مشاهده شد. غوطه وری سوخ ها در کاهش زمان تشکیل غنچه در مقایسه با محلول پاشی موثرتر بود. قطر گل در تیمار 1500 سایکوسل به روش غوطه‌وری در حداکثر بود اما با تیمار 1000 سایکوسل به روش غوطه‌وری و تیمار یونیکونازول 10 میلی‌گرم در لیتر محلول‌پاشی تفاوت معنی داری نداشت. فعالیت آنزیم کاتالاز نیز در گیاهان محلول پاشی شده بیشتر از تیمارهای غوطه وری بود. بیشترین میزان فعالیت این آنزیم با 54.23 درصد افزایش نسبت به تیمار شاهد در تیمار سایکوسل 1500 میلی‌گرم در لیتر مشاهده شد. همچنین بیشترین فعالیت آنزیم گایاکول پراکسیداز در گیاهان محلول پاشی شده با 1000 میلی گرم در لیتر سایکوسل به دست آمد که تفاوت معنی داری با تیمار 1500 سایکوسل در روش غوطه وری نداشت. لذا با توجه به اینکه تیمار یونیکونازول 10 میلی گرم در لیتر تاثیر معنی داری در مقایسه با دیگر تیمارها در کاهش ارتفاع نشان داد، بنابراین استفاده یونیکونازول با غلظت 10 میلی گرم در لیتر به صورت غوطه وری و محلول پاشی در تولید گیاه گلدانی لیلیوم توصیه می شود.

the effect of different concentrations of uniconazole and cycocel and their application method on vegetative growth and biochemical properties of lilium hybrids (longiflorum × asiatic cv. eyeliner)

introduction plant size control is one of the most important factors in the production of ornamental plants. plant size can be limited by a variety of methods, including genetic control, environmental conditions, and the use of plant growth retardants. lily (lilium sp.) is one of the most important cut flowers with different species and cultivars. some lilies can grow up to one meter in height. usually the appropriate height of the stem for pot use is 40-30 cm, which is achieved by using growth regulators. this study aimed to investigate the role of uniconazole and cycocel to control height, quantitative and qualitative characteristics of lilium.materials and methods this study was carried out in a factorial experiment based on completely randomized design. uniconazole (0, 5 and 10 mg l-1) and cycocel (0, 1000 and 1500 mg l-1) were the first factor and application methods of the above compounds (immersion application and foliar application) was the second factor. disease-free bulbs (with a circumference of 15 cm) lily (longifiorum × asistic cv. eyeliner) was purchased from saei gol company in tehran. to apply the immersion treatment, the bulbs were immersed in a solution of cycocel (ccc) and uniconazole (un) for 7 minutes before planting. then they were planted in plastic pots. in foliar spraying treatments, the bulbs were first planted in pots and when the stem height reached 10 cm, they were sprayed with ccc and un. water was used for control treatment. leaf number, plant height, total chlorophyll, total phenol, flower diameter, enzyme activity (ppo, gpx or cat) and time of budding were measured. analysis of variance was performed using sas software and mean comparisons were analyzed by the least significant difference test.results and discussion the effect of growth retardant, the application method and their interaction was significant on stem height. the shortest plants were observed in foliage application of 10 mg l-1 un which was not significantly different from the concentration of 10 mg l-1 un in immersion method. the mechanism of growth retardants is to inhibit the biosynthesis of gibberellins. therefore, they act as anti-gibberellins to reduce plant height. uniconazole inhibits the biosynthesis of gibberellins by blocking kaurene oxidase, a p450 enzyme. the largest diameter of lily flowers was observed in immersion application of 1500 mg l-1 ccc however, there was no significant difference between flower diameter of mentioned treatment with immersion method of 1000 mg l-1 ccc and foliar application of 10 mg l-1 un. growth retardants increase endogenous cytokinin levels, resulting in increased cell division and improved flower growth and flower diameter. the effect of growth retardant on number of leaves was significant. the highest numbers of leaves were observed in 1000 and 1500 mg l-1 ccc. the effect of growth retardant, the application method and their interaction was significant on chlorophyll and phenol contents. the highest chlorophyll content was observed in immersion application of 10 mg l-1 un. growth retardants appear to increase chlorophyll content due to increased cytokines. the results of this study showed an increase in total phenol in plants treated with uniconazole 10 mg l-1. growth retardants have been reported to increase phenol content by increasing plant resistance to environmental stresses. catalase enzyme activity was significantly affected by growth retardant. the highest activity of cat enzyme was related to ccc at 1500 mg l-1. the effect of growth retardant and their interaction was significant on gpx enzyme activity. the highest enzyme activity was obtained in plants sprayed with 1000 mg l-1 ccc. growth retardants have been reported to increase enzyme activity, causing plant resistance to environmental stresses and delaying lipid peroxidation and membrane degradation.conclusion considering that one of the most important goals in the present study was the production of dwarf lilium, it can be said that uniconazole 10 mg l-1 (foliar application and immersion) had a significant effect in controlling stem height compared to other treatments. the effect of this treatment on other traits such as flower diameter, total chlorophyll and total phenol was also significant. the time of budding, leaf number and activity of cat and gpx enzymes was better in cycocel treatment with a concentration of 1500 mg l-1. therefore, the use of uniconazole can be recommended for the production of dwarf plants, considering that it works better in two important traits, including controlling stem height and increasing flower diameter. it is also suggested that since the cycocel treatment was effective in increasing enzymatic activity, the effect of this treatment on plant resistance to environmental stresses should be investigated.