اثر نسبت نيتروژن (نيتراتي و آمونيومي) بر ميزان ماده خشك و محتوي رنگيزه هاي فتوسنتزي و تركيبات بيوشيميايي قند و پرولين اندام هاي هوايي و ريشه گياه دارويي بالنگو(lallemantia royleana L.) تحت شوري

Effect of nitrate and ammonium nitrogen ratio on dry matter content and content of photosynthetic pigments and biochemical components of sugar and proline of aerial parts and root of lallemantia royleana L. under salinity

تنش شوري يكي از عوامل مهّم كاهش رشد و عملكرد گياهان دارويي به خصوص در مناطق خشك و نيمه خشك مي‌باشد. مطالعه اي به منظور ارزيابي تحمّل به شوري و تأثير منابع مختلف كودهاي نيتروژنه و نحوه اعمال آن بصورت فاكتوريل در سه تكرار در گلخانه پژوهشي دانشگاه شاهد بر گياه دارويي بالنگو صورت گرفت. عامل شوري (آب مقطر، 40، 80، 120 و 150 ميلي مولار) و نسبت منبع نيتروژن (نيترات:آمونيوم) (0 : 100، 75 : 25، 50 : 50، 25 :75 و 100 : 0) در نظر گرفته شدند. نتايج نشان داد محتواي پرولين، قند، رنگيزه‌هاي فتوسنتزي، محتواي عناصر سديم و پتاسيم اندام هوايي و فعاليت آنزيم نيترات ردوكتاز و ميزان ماده خشك اندام زميني و خشك اندام هوايي تحت تاثير شوري و منبع تغذيه نيتروژن قرارگرفتند. مقايسه ميانگين نشان داد شوري باعث افزايش 55/5 درصدي پرولين و 24/9 درصدي قندهاي محلول در اندام‌هاي هوايي گرديد. ازطرف ديگر با افزايش شوري ميزان سديم به طور معني‌داري افزايش يافته(18) و سديم مانع جذب پتاسيم(12) شد. همچنين شوري باعث كاهش فعاليت آنزيم نيترات ردوكتاز(24 درصد) در بالنگو گرديد. اما افزايش نيتروژن آمونيومي باعث افزايش فعاليت آنزيم نيترات ردوكتاز در برگ (16/3 درصد)، ساقه (3/35 درصد) و ريشه (7/16 درصد) گرديد. از سوي ديگر افزايش نسبت نيتروژن آمونيومي باعث كاهش وزن تر و خشك اندام زميني و اندام هوايي گياه بالنگو شد كه اين نشان دهنده ثر سوء آمونيوم بر روي گياه بالنگو بوده است.

Introduction: Lallemantia royleana L. is a plant of the Lamiaceae family. Its grain has about 18% protein and 20% fat content. Salinity stress is one of the important factors in reducing the growth and yield of medicinal plants, especially in arid and semi-arid regions. Nitrogen deficiency in arid and semi-arid soils is also significant. The relative adaptation of plants for the use of nitrate and ammonium is different. Therefore, the reaction of plants, especially medicinal plants, is different in the choice of the form of nitrogen (nitrate or ammonium) after absorption and prior to entering the organic nitrogenous compounds, thus, it becomes more complicated in terms of salinity stress. This study aimed to evaluate the effect of different sources of nitrogen fertilizers and salt tolerance on balangue herbs. In this study, the response of the herbal medicine to the nitrogen source is evaluated under salinity conditions. Material and Methods: This research was carried out in the research greenhouse of the Soil Department of Faculty of Agriculture, Shahed University of Tehran. The study was factorial based on randomized complete block design (RCBD) in three replications and in early stages of seedlings growth. The treatment composition included the product of salinity factor levels and the ratio of nitrogen change. Factor of salinity (control, 40, 80, 120 and 150 mM) and nitrogen source levels (Hoagland, 0:100, 25:75, 50:50, 75:25 and 0:100 ammonium: nitrate) and were done in a greenhouse. The greenhouse temperature is 22-25 ° C and the intensity of light is provided by a combination of fluorescent lamps and tungsten lamps. Before applying the factors, seeds were first disinfected 30% with sodium hypochlorite 5% and then washed with distilled water several times. After germination of the seeds and proper growth of root and stem, seedlings were transferred to the hydroponic culture medium. The data were analyzed using SAS software, including statistical analysis of variance of data related to different traits. Charts were also drawn by EXCEL software. Duncan test was used to compare the means. Results and Discussion: The experiment result showed that content of proline, glucose, pigments photosynthesis, and shoot elements content of sodium and potassium and nitrate reductase enzyme activity and morphological dry ground and shoot dry weight were significant, respectively. Comparison of the means was showed that salinity content of proline (55.5 %), glucose (24.9 %) increased in the shoot. In the other hand, with increasing salinity, sodium rate (18 %) increased significantly, potassium uptake (12 %) was prevented by sodium. Also, salinity reduced the nitrate reductase activity (24%) in balango. However, the increase of ammonium nitrogen increased nitrate reductase activity in leaf (16.3%), stem (35.3%) and root (16.6%). While, an increase in the ratio of ammonium nitrogen resulted in a decrease in fresh and dry weight of the balango and airspace of the plant, it represents the destructive effect of ammonium on the plant