{"title":"تأثیر دما و تنش خشکی بر جوانه¬زنی بذر تاج خروس خزنده (Amaranthus viridis L.) و خوابیده (Amaranthus blitoides S. Watson)","authors":"مرجان دیانت","doi":"10.22067/jpp.v31i4.61569","DOIUrl":"https://doi.org/10.22067/jpp.v31i4.61569","url":null,"abstract":"Introduction: Slender amaranth (Amaranthus viridis L.) and prostrate pigweed (Amaranthus blitoides S. Watson) are two common weeds in vegetables and summer crop fields of Iran. The two Amaranthus species have all the attributes required by ecologically successful annual weeds: rapid growth, early reproduction and continuous seed production. Knowledge of the germination requirements of these weeds will helps determine the proper conditions for germination and emergence and allow better management of them. Water and temperature are determining factors for seed germination of weed. Both factors can, separately or jointly, affect the germination percentage and germination rate. Water stress is one of the main constraints on plant growth and the most common environmental stresses around the world. Water stress affects the different aspects of plant growth and causes reduction and delay in seed germination. Seed germination of all plant species requires a minimum of water to be absorbed and swelled and that is why osmotic potential should not be less than a certain amount. \u0000Materials and Methods: Seeds were harvested from vegetable fields of Karaj. For breaking dormancy, seeds were treated with concentrated sulfuric acid for two minutes. Two experiments were conducted at Islamic Azad University, Science and Research Branch, Ecology lab, in 2016. First experiment was based on completely randomized design with 4 replications .The seeds were treated with different temperatures (5, 10, 15, 20, 25, 30, 35, 40 and 45oC). Germination percentage and germination rate were measured and seed were considered to have germinated with the emergence of the radical. Intersected lines model is used to determine the cardinal temperature. Second experiment was conducted to determine the effects of simulated dry conditions (use PEG) and temperature on seed germination of slender amaranth and prostrate pigweed. Exposure to polyethylene glycol (PEG-6000) solutions has been effectively used to mimic drought stress with limited metabolic interferences as those associated to the use of low molecular weight. Over a 21d period, germination was studied in 5, 10, 15, 20, 25, 30, 35, 40 and 45°C constant temperatures and water potentials of 0, -0.2, -.04, -.06, -0.8 and -1.0 MPa. The number of 25 seeds were placed into petri dishes, then 10 ml of prepared drought solution was added to each petri dishe. Petri dishes, then, were placed in germinator in circadian alternation of 12 h light and 12 h darkness, under 9 temperatures and a relative humidity of 65 %. Data were statistically analyzed using analyses of variance in the SAS 9:1 software. Probabilities of significance were used to indicate significance among treatments and interaction effects. FLSD (p<0.05) was used to make comparisons among treatments. \u0000Results and Discussion: In the first experiment, analysis of variance showed that temperature had a significant effect on seed germination percentage and germination rate. Base, o","PeriodicalId":31229,"journal":{"name":"Majallahi hifazati giyahan","volume":"31 1","pages":"690-699"},"PeriodicalIF":0.0,"publicationDate":"2018-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48708192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
مهناز کیخسروی, حسین صادقی نامقی, مجتبی حسینی, غلامحسین مروج
{"title":"بررسی پویایی جمعیت شته ی رز Macrosiphum rosae (L.)) روی ارقام مختلف گل رز (Rosa hybrida) و تنوع زیستی شکارگر های آن در مشهد","authors":"مهناز کیخسروی, حسین صادقی نامقی, مجتبی حسینی, غلامحسین مروج","doi":"10.22067/JPP.V30I1.45882","DOIUrl":"https://doi.org/10.22067/JPP.V30I1.45882","url":null,"abstract":"شته ی Macrosiphum rosae L یکی از مهم ترین آفات گل رز در ایران و سایر نقاط جهان محسوب می شود. تغییرات جمعیت این شته روی شش رقم مختلف گل رز با نمونه برداری های هفتگی از اواخر اسفند 1391 تا آخر اسفند 1392 مورد بررسی قرار گرفت. همزمان، تنوع زیستی بندپایان شکارگر شته رز در ایستگاه های مورد مطالعه با استفاده از شاخصهای تنوع زیستی شانون- وینر و یکنواختی پیلو محاسبه شد. نتایج نشان داد که شته ی رز در طول فصل زراعی روی هر 6 رقم دارای دو اوج جمعیتی در بهار و پاییز می باشد. تجزیه و تحلیل آماری داده ها نشان داد که میانگین تعداد شته روی ارقام رز مورد ارزیابی دارای تفاوت معنی دار بودند (P<0/01). رقم های بلسینگ و آیس برگ به ترتیب با میانگین تراکم 3/43±254/62 و 2/10±656/12 شته در نمونه دارای بیش ترین و کمترین آلودگی به شته ی رز بودند. ارقام جوزفین بروس (با میانگین تراکم 9/30±245/56 شته)، پیکادیلی (با میانگین تراکم 1/44±789/52 شته)، مینیاتور (با میانگین تراکم 8/24±121/41 شته) و فیری (با میانگین تراکم 9/24±598/35 شته) به ترتیب در بین دو رقم بلسینگ و آیس برگ قرار گرفتند. محاسبه ی مقادیر شاخص تنوع زیستی شانون- وینر شکارگرهای شته ی رز روی ارقام مختلف نشان داد که بیشترین مقدار این شاخص (65/1) مربوط به رقم جوزفین بروس در تاریخ 10/02/1392، و کمترین مقدار شاخص (38/0) مربوط به رقم آیس برگ در تاریخ 29/09/1392 برآورد شد. همچنین، کمترین مقدار شاخص یکنواختی پیلو مربوط به رقم جوزفین بروس (49/0) در تاریخ 17/02/1392 و بیشترین مقدار آن مربوط به رقم آیس برگ (98/0) در تاریخ 29/09/1392 برآورد شد. در میان شکارگرهای شته رز، مگس های گل با هفت گونه و فراوانی 91/38 و کفشدوزک ها با هشت گونه و فراوانی 12/30 به ترتیب غالب ترین شکارگرها بودند و سایر گونه های شکارگر بعد از این دو خانواده قرار گرفتند.","PeriodicalId":31229,"journal":{"name":"Majallahi hifazati giyahan","volume":"30 1","pages":"164-173"},"PeriodicalIF":0.0,"publicationDate":"2016-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68594281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}