Background & Aim:Currently, the use of beneficial microorganisms with the hope to reduce the adverse effects of drought has been the focus of attention. In present study, the effects of plant growth promoting rhizobacteria (PGPR) and drought stress on essential oil (EO) and physiological status of Thymus daenensis Celak, were investigated. Experimental: The experiment was arranged as a factorial pattern in a randomized complete design with three replications. Factors were four irrigation regimes included: well-watered (A: absence of stress), irrigation after depletion of 20-25% of field capacity (L: low stress), irrigation after depletion of the 35-40% of field capacity (M: mild stress) and irrigation after depletion of the 55-60% of field capacity (S: severe stress). Also, two PGPR treatments, non-inoculation (C: control) and inoculation with PGPR were conducted. Results:The results showed that drought stress reduced root and shoot dry weight, relative water content, photosynthetic pigments and gas change parameters but PGPR inoculation improved all of them. Proline, malondialdehyde, electrolyte leakage and stomatal resistance increased with increasing water stress, but PGPR inoculation ameliorate these increases in corresponding treatments. PGPR inoculation increased essential oil production although this increase was not statistically significant but water stress decreased it.Recommended applications/industries:The results suggest that PGPR inoculation could be an excellent strategy to alleviate adverse effects of water stress in Thymus daenensis cultivation in drought stress conditions. Therefore, farmers in semiarid regions could produce T. daenensis by using of PGPR at low water stress for the highest economic amount of extracted essential oil. تفاصيل المقالة

Salinity stress is a limiting factor for plant growth and production. To reduce the salinity effects, humic acid was applied in soil, and its mitigation effect was studied on Satureja khuzistanica Jamzad. The research was conducted as a factorial experiment based on a completely randomized block design with four replications at Lorestan University. The factors included salinity stress (0, 25, 50, 75, and 100 mM NaCl) and humic acid (0, 10, 20, 30, and 40 mg/kg soil). Results showed that salinity stress decreased plant height, dry weight, leaf number, root length, chlorophyll, and carotenoids. However, it significantly increased flavonoid contents and SOD, CAT, and GR activities. Essential oil (EO) quantity and quality were affected by salinity. The EO percentage and yield decreased by salinity. Forty-three constituents were identified, among which carvacrol, γ-terpinene, α-terpinene, myrcene, p-cymene, α-thujene, citronellol, and α-pinene were the major compounds according to their contents and formed more than 94% of the EO. The percentage of some of the other constituents decreased to zero under specific salinity and humic acid treatments. The application of humic acid could mitigate salinity effects on growth and EO production. However, there was an interaction between salinity and humic acid on EO yield and quality. It seems that the application of humic acid is useful for improvement EO yield of S. khuzestani, but the amount of its application depends on the EO consumers’ favorite. تفاصيل المقالة

Soybean (Glycine max L.) is considered as one of the major sources of oil and protein. In this study, the effects of vermicompost (VC) and sulfur (S) on soybean photosynthesis responses, yield, and grain quality were studied. To this end, a split-plot design field experiment based on randomized complete blocks with nine treatments and three replications was conducted in Aligudarz city Lorestan province, Iran in 2017. The first factor included Vermicompost treatments (0, 4 and 8 t h-1) as the main plot and the second factor included sulfur treatments (0, 250 and 500 kg h-1) as the sub plot. Results of the present study revealed that VC application significantly increased the stomatal conductance (gs), transpiration rate (E), net photosynthetic rate (PN), chlorophyll a (Chl a), chlorophyll b (Chl b), chlorophyll a+b (Chl a+b), carotenoids (Car), grain yield (GY), grain oil content (GOC), and grain protein content (GPC) of soybean. Furthermore, S application (250 kg h-1) improved the important traits in comparison to the control treatments. A significant interaction was found between VC and S treatments, suggesting the combined application of VC and S may improve soybean physiological responses, yield and grain quality in comparison to the VC and S treatments alone. تفاصيل المقالة

Despite the increasing rate of nanoparticles (NPS) production and their application in agriculture, few studies have focused on their effect on plant growth. So, the present research was conducted in laboratory and greenhouse conditions. First, superparamagnetic iron oxide nanoparticles (SPIONS) with a humic acid coating (Fe3O4/HA) were synthesized in laboratory conditions by the chemical coprecipitation method. The effectiveness of the synthesized nanoparticles in vegetative growth and nutrients uptake of chrysanthemum cut flower (Chrysanthemum morifolium) were evaluated in greenhouse conditions with four replications in a completely randomized design. The treatments consisted of 10, 20 and 40 mg/L of pure Fe from the source of Fe3O4/HA NPS and 1.4 mg/L of pure Fe from two sources of iron chelates which contained Fe-EDTA(Fe-Ethylenediaminetetraaceticacid) and Fe-EDDHA [Fe-ethylenediaminedi(O-hydroxy phenylaceticacid)] were considered as control treatments in the open hydroponic cultivation system. The results of the laboratory experiment indicated that the synthesis of Fe3O4/HA by the chemical coprecipitation method led to the production of nanoparticles with an average diameter of 8.38 nm and superparamagnetic properties. The greenhouse experiment demonstrated that the application of Fe3O4/HA significantly increased Fe uptake, chlorophyll and vegetative growth of the plants versus the control treatments. The highest rates of Fe, N, P, K, Ca, Mg, Mn, and B uptake were observed at the NP rate of 20 mg/L. The branch number per plant, stem height, and total dry weight of the plants were significantly increased by 25, 38, and 39.5% versus the treatment of Fe-EDTA and by 50, 36, and 48% versus the treatment of Fe-EDDHA, respectively. It is concluded that magnetite NPs with a humic acid coating resolved Fe deficiency and increased chrysanthemum growth. تفاصيل المقالة

Recently, the use of superparamagnetic iron oxide nanoparticles (SPIONS) as a new and promising source of iron in agriculture has been suggested that further investigation is needed before extensive field use. In a greenhouse experiment, the effect of coated magnetite nanoparticles with humic acid (Fe3O4/HA NPs) was investigated on iron deficiency chlorosis and photosynthesis efficiency compared to iron chelates of Fe-EDTA (Fe-Ethylenediaminetetraacetic acid) and Fe-EDDHA [Fe-Ethylene diamine-di (o-hydroxyphenylacetic acid)] as control treatments in chrysanthemum cut flower (Chrysanthemum morifolium) in the open hydroponic cultivation system. The feasibility of absorption and translocation of nanoparticles in the plant was evaluated by vibrating sample magnetometry (VSM). The results of tracing by magnetization measurement was demonstrated that NPs penetrated in root and transferred to the aerial parts of chrysanthemum. The greenhouse experiment demonstrated that the application 20 mg/L Fe3O4/HA NPs in nutrient solution significantly (P تفاصيل المقالة

آزمایش مزرعه‌ای، بر اساس سناریوهای استاندارد مورد تأیید IPCC (A1B، A2، B1) توسط مدل گردش عمومی جو (HadCM3) با استفاده از مدل ریز مقیاس (LARS-WG) با هدف بررسی اثر تغییر اقلیم بر پاسخ مراحل فنولوژیک گیاهان سه کربنه، در مزرعه تحقیقاتی دانشکده کشاورزی دانشگاه لرستان در دو سال زراعی 93 و 94 در یک مکان با تیمار اجزاء مکمل مخلوط ماشک برگ درشت و جو در 5 سطح، علف هرز در چهار سطح و کمپوست نیز در چهار سطح با آزمایش فاکتوریل 5×4 در قالب طرح بلوک های کامل تصادفی برای سال هدف 2055 میلادی (1445 شمسی) به‌صورت دیم اجراء شد. پارامترهای اقلیمی دما، بارندگی و تابش روزانه در دوره زمانی مورد مطالعه با استفاده از مدل LARS-WG شبیه سازی شدند. نتایج نشان داد که کاهش طول دوره رشد و عدم برخورد با دماهای فوق مطلوب و فرار از تنش‌های خشکی آخر فصل به علت منطبق بودن دوره رشد با فصل رشد، کاهش ریسک مخاطرات محیطی در سال های آتی را سبب شده و پایداری عملکرد نیز حاصل می‌گردد. بنابراین با وجود کاهش احتمالی تبخیر و تعرق گیاهان مرجع، شرایط زراعی آینده در خرم آباد به‌منظور تولید علوفه ارگانیک و کنترل بیولوژیک علف‌های هرز تحت اثر تغییرات اقلیمی، حاکی از میسر بودن امکان کشت بوده و اثرات منفی تغییر اقلیم بر تولید محصول کاسته می‌شود. تفاصيل المقالة

جهت تعیین اثر کشت مخلوط بر رشد و نمو علف‌های هرز، آزمایشی در مزرعه تحقیقاتی دانشکده کشاورزی دانشگاه لرستان در دو سال زراعی 94-1393 و 95-1394 بصورت فاکتوریل در قالب طرح بلوک‌های کامل تصادفی با سه تکرار و در یک مکان بصورت دیم با فاکتور علف هرز در 4 سطح (وجین کامل، یکبار وجین، دو بار وجین و عدم وجین) و فاکتور مخلوط افزایشی در 5 سطح 100:0 (کشت خالص جو)، 100:40 (ماشک برگ درشت:جو)، 100:70، 100:100 و 0:100 (کشت خالص ماشک برگ درشت) اجراء شد. کشت مخلوط ماشک برگ درشت:جو در مقایسه با تیمارهای خالص، با افزایش راندمان کنترل علف‌های هرز (WCE) بیانگر کاهش تعداد گونه، رشد و نمو آن‌ها بود، از طرفی عامل سال، بر نقش سیستم مخلوط و تکمیل اثر این روش بر رشد و نمو علف‌های هرز موثر بود، به‌طوری‌که در سال اول و دوم، نسبت 100:100 و 100:70 (ماشک برگ درشت:جو) در ممانعت از توسعه فلور طبیعی، ترکیب مناسبی شناخته شدند. تفاصيل المقالة