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Abstract Savory (Satureja rechingeri L.) is one of Iran’s most important medicinal plants, having low irrigation needs, and thus is considered one of the most valuable plants for cultivation in arid and semi-arid regions, especially under drought conditions. The current research was carried out to develop a genetic algorithm-based artificial neural network (ΑΝΝ) model able of simulating the levels of antioxidants in savory when using soil amendments [biochar (BC) and superabsorbent (SA)] under drought. Data under different watering schemes and different levels of soil amendments showed that both BC and SA have mitigating effects over drought stress by optimizing enzymatic and non-enzymatic antioxidant traits (POD, CTA, and APX enzymes). Specifically, using biochar and superabsorbent led to improved homeostasis under water deficit as reflected by lower MDA levels. An ANN model with a 3-10-6 topology was found to be the best model to predict polyphenols (PHE), proline (PRO), peroxidase (POX), catalase (CAT), ascorbate peroxidase (APX) levels, and indicator of oxidative stress malondialdehyde (MDA). The model’s efficiency was established using the R-value as the statistical parameter, and simulated GA-ANN data were highly correlated with experimental findings. Across enzymatic antioxidants, APX had the best model fit, having an R-value of 0.9733. On the other hand, POX had a lower predictive correlation (R = 0.8737), indicating a lower capacity of the ANN system in forecasting this parameter. On the other hand, MDA (R = 0.9690) had an elevated assimilation performance over PHE (R = 0.9604) and PRO (R = 0.9245) levels. The current study shows the potential of the ANN model in predicting the content of enzymatic and non-enzymatic antioxidants in savory plants under drought stress as a non-invasive, low-cost experimental alternative.

Satureja rechingeri is a valuable medicinal plant, but its growth can be significantly impacted by water deficit stress. To investigate the effects of biochar (BC) and hydroretentive polymers (HPs) on various eco-physiological traits of savory under a water deficit, an experiment was conducted over two consecutive cropping seasons (2017–2019). A randomized complete block design with a split-plot factorial arrangement and three replications was used. The treatments consisted of three levels of irrigation (95 ± 5, 75 ± 5, and 55 ± 5% FC), which were applied to the main plots, and combinations of two levels of biochar and two levels of HPs, which were applied to subplots. The results show that a water deficit reduced the relative water content (RWC), chlorophyll content, and dry matter yield of the shoots. Furthermore, the activity of catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX), and malondialdehyde (MDA) increased in two-year-old plants. The MDA content significantly decreased by 15.6% in the second year compared to in the first year under a water deficit. The application of HPs caused a decrease of 26.4%, 32.5%, and 27.5% in POD, CAT, and APX enzyme activities, respectively, compared to their control levels. In the biochar treatment, there was a significant reduction in the activity of POD, APX, and CAT in the leaves.

IntroductionRain-fed Lentil (Lens culinaris Medik.) is vulnerable to weed competition because of its tiny stature, slow establishment, and limited vegetative growth. Weed control is necessary for maximum seed yield and seed quality. Crop yield losses are primarily a result of competition with weeds for nutrients, moisture and space. Therefore, weed control at this period plays an important role to gain high roduction. Although the vast majority of lentil production is under rain-fed conditions, there is a little published information on weed control with herbicides in rain-fed lentils. Herbicides due to efficiency and expense savings play a essential role in weed control. The purpose of this research was to determine the best time to application effective herbicides in weeds control for the maximum rain-fed Lentil production in Khorramabad. Materials and MethodsThe Lentil (Lens culinaris Medik.) field experiment was carried out as split plot based on complete randomized block design with three replications during 2017-2018 in Khorramabad (48.21°E, 33.29°N, 1170 m above sea level, 450 mm average yearly precipitation) Iran. The following herbicides were used: Oxyfluorfen (EC 24%) 1 Li ha-1, Isoxaflutole (SC 480) 200 Ml ha-1, Flumetsulam(WG 800) 20 g ha-1, Metribuzin (WP 70%) 500g ha-1, Pendimethalin Aria(EC33%) 4 li ha-1, Pendimethalin Prowl (CS45.5%) 4li ha-1, Imazethapyr (SL10%) 350 ml ha-1 and Pendimethalin prowl 2li ha-1plus Imazethapyr 350 ml ha-1. Herbicide applicatioin time at 3 levels; IAP application (Immediately after planting), PRE application and IBCE (eraly post herbicide application at fourth lentil node stage) was assigned to the main and sub plots respectively. The fields were in wheat cultivation in the year before the experiments. The soil at the test sites was a silty loam with a pH of 7.9 and organic matter of 1.11%. Lentil was sown at a density of 75 kg seed ha-1 by hand on December 21, 2017. Herbicides were sprayed with an electric knapsack sprayer MATABI (calibrated to deliver 300 L ha-1. In order to evaluate the effect of treatments on weeds density and biomass, at the beginning of lentil flowering, sampling was done from a surface of 0.3 m-2 area and weed density and weed biomass recorded. At lentil physiological maturity, the yield and yield components were measured by harvesting lentil plants from a 1-m2 area in each plot (Izadi & Maghsoudi, 1400). The data were subjected to the analysis of variance using SAS. Means were compared using Duncan's Multiple Range test at P=0.05 level of significance. Results and DiscussionThe results indicated that the lowest weed density and weed biomass were associated with Flumetsulam and Prowl plus Imazethapyr. The average weed densities for the postemergence and preemergence treatments of the eight evaluated herbicides were 14.9% and 31.0% lower, respectively, compared to the herbicide application immediately after planting. The least herbicide injury effects on the Lentil crop were assigned to the Pendimethalin Aria, Pendimethalin Prowl, Prowl plus Imazethapyr, Imazethapyr and Flumetsulam. In the case of Oxyfluorfen herbicide, weed density for early postemergence application treatment was 84.1% lower than in PRE application. In the case of Isoxaflutole herbicide, the mean weed density for application immediately after planting was 79.3% lower than for early post-application. In the case of Flumetsulam herbicide, the mean of weed biomass for application immediately after planting was 73.3% and 66.6% less than preemergence and early post-application, respectively. With the exception of Flumetsulam herbicide, there was no significant difference between the different herbicide application times in terms of weed biomass. The highest average Lentil grain yield per unit area was observed when Flumetsulam herbicide was applied immediately after planting. On the other hand, the lowest average Lentil grain yield per unit area was recorded when Isoxaflutole herbicide was applied immediately after planting. No significant differences in Lentil grain yield per unit area were found between the different application times for the herbicides Metribuzin and Imazethapyr. Based on cluster analysis grouping of relative efficacy of control treatments, immediately after planting application or preemergence application of Flumetsulam and early postemergence application of Imazethapyr were better than the other herbicide treatments for Lentil weed control, whereas the lowest relative efficacy was related to preemergence application of Oxyfluorfen, immediately after planting application of Isoxaflutole and Metribuzin, and preemergence application of Pendimethalin Arya. ConclusionBased on the results of this research, the application of flumezolam immediately after planting (20 g ha-1) and imazatapir( 350 ml ha-1) as pre-emergence application have had more efficiency for weed control in lentil than other herbicide treatments, while the pre-emergent application of oxyfluorfen, the application immediately after planting of isoxaflotel and metribyozin have had the effects of plant burning on lentil crops and the pendimethalin Aria herbicide is not recommended in lentil farms because of to the lack of control of broadleaf weeds under normal conditions in lentil fields. In general, among the experimental treatments, in terms of the level of control efficiency and the level of safety for the lentil crop, the application of flumetsulam immediately after planting was the best herbicide treatment.

Introduction: One of the new methods in reducing the pollution caused by the use of herbicides and other agricultural chemical pesticides is the use of resistant and degrading bacterial isolates of these herbicides. This study was conducted to isolate and identify resistant bacterial strains from the soil of wheat fields using the three herbicides of Othello, Atlantis, and Puma Super. Materials and methods: To isolate and characterize resistant bacteria, samples were collected from wheat fields treated with Othello, Atlantis, and Puma Super herbicides. Isolates were selected based on the growth on the Standard Succinate Medium containing 10 percent of the mentioned herbicides. The representative isolates were identified based on biochemical tests and amplification of the 16S rRNA gene. Also, the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the representatives were measured. Results: A total of 17 isolates could grow on a growth medium containing 10% of the tested herbicides. Based on the valid biochemical and molecular test results, the representative strains were identified as Stenotrophomonas maltophilia, Ensifer adhaerens, Xanthomonas sp., Pseudoxanthomonas sp., and Acinetobacter sp. The Minimum inhibitory concentration (MIC) and Minimum Bactericidal Concentration (MBC) were attributed to Othello (0.28 and 0.4) and Atlantis herbicides (0.35 and 0.5) belonging to Acinetobacter and Xanthomonas (0.45 and 0.67) for Puma Super herbicides. Discussion and conclusion: According to the results of this study, herbicide-resistant bacteria identified in this study can be useful in plant biotechnology applications in polluted areas and can reduce environmental pollution regarding using these herbicides. However, further studies are needed in order to identify the degrading potential of the resistant strains.

To evaluate the effect of time and rates of imazethapyr application on weed control of bean field an experiment was conducted in Agricultural Research Station of Lorestan University based on the randomized complete block design (RCBD) with three replications in 2015-2016. In this experiment, the effects of pre planting, pre emergence and post emergence applications of imazethapyr with different rates (0.25, 0.5, 0.75 and 1 lit.ha-1) and pre planting imazethapyr mixed with soil (1 lit.ha-1) plus post emergence with weed control in two levels (control and non- control) was studied. The most important weed species in the experimental site were safflower (Carthamus oxyacantha), catchweed bedstraw (Galium tricornutum), wild mustard (Sinapis arvensis), cow cockle (Vaccaria grandiflora), chickweed (Conringia orientalis). Weed density in weedy control condition was estimated to be 133 plants.m-2. The results showed the maximum percentage of weed dry weight loss, as compared to not controlling weed due to imazetapir post-treatment application of 0.75 and 1 L.ha-1, was 86.95%. Also highest average root length (12.46 cm), root dry weight (95 g), number of branches (5.33), number of seeds per pod (9.3) and seed yield were observed in hand weeding. The highest plant height (88.33 cm) belonged to weed control treatment, the highest LAI (2.59) in herbicide usage, in pre planting (0.25 lit.ha-1), the highest average number of pod per plant (10 pod), number of pod per m-2 (100 pod) and biological yield (33367.1 kg.ha-1) resulted from pre emergence herbicide application (0.5 lit.ha-1). The highest of 100 seed weight (109.6 g) for pre planting herbicide application (1 lit.ha-1) plus herbicide post emergence application (1 lit.ha-1) was seen. The results also showed that, after hand weeding, the best concentration of imazethapyr pre emergence application (0.5 lit.ha-1) that it could decrease weed density by 99% as compared to not controlling weed. This treatment (imazethapyr pre emergence application (0.5 lit.ha-1) was the best treatment. Higher concentrations of herbicides also decreased bean yield because of burning, reduction in leaf area and photosynthesis.

Introduction Chickpea is important due to its grain high protein. Chickpea is weak to compete with weeds because of the retard growth at the early stages. Therefore, weed control at this time plays an important role to gain high production. Chickpea is being grown in both dry land and irrigated systems, and growers in both systems are finding weed control to be a major obstacle to profitable production. Weed control is essential for maximum seed yield and seed quality. Selection of the herbicide plus cultivator between rows can effectively control weeds. Herbicide due to efficiency and cost savings play a basic role in weed management. Application of Isoxaflutole controlled weeds in chickpea fields with very low phytotoxicity on chickpea. But the risk of crop injury from Isoxaflutole has been reported to be greatest in soils with low organic matter content and high pH. The only herbicide registered for chickpea in Iran, is pyridate in 1998.Considering the importance of agriculture chickpea in Kermanshah and high cost of hand weeding in the fields, this study was projected to achieve the most appropriate herbicides in combination with mechanical methods (row cultivator), in order to optimally control weeds and increase the yield of chickpea. The objective of this research was to identify efficacious chemical weed-control plus cultivation options for rainfed production of chickpea in Kermanshah. Materials & Methods The experiment was carried out as strip plot based on complete randomized block design with four replications during 2014-2015 in Kermanshah province. The main factor included inter-row cultivation and without inter-row cultivation and the sub factor consisted of applications of Linuron (pre planting), Isoxaflutole (post emergence), Metribuzin (pre emergence), Paraquat (post emergence), Pendimethalin (pre emergence), Pyridate (post emergence) at rates 0.67, 0.48, 0.42, 0.05, 0.82, 1.5 kg a.i./ha respectively and hand weeding. Chickpea (ILC482) were sown on March 3th placing 45 seeds m-2 in rows 0.6 m apart. All herbicides were sprayed with an Elegance 18 electric knapsack sprayer equipped with flooding nozzle and calibrated to deliver 300 L/ha of spray solution at a pressure of 2.5 bar. Herbicides were applied in one-half of each plot, and the other half kept as its control. The inter-row cultivation was applied on April 29th 2014. Percent weed population and biomass reduction in all treatments was measured separately for each weed species by counting the number of weeds 30 days after treatment within two fixed 1m2 quadrates that were dropped in the treated and untreated halves of each plot. The data were subjected to the analysis of variance using SAS. Means were compared using Duncan's Multiple Range test at P=0.05 level of significance. Results & Discussion Results showed that cultivation between rows reduced population of Lambs quarters and Redroot Pigweed significantly. Linurin and Paraquat could not provide acceptable biomass and population reduction. But Pyridate, Isoxaflutole and Metribuzin could control satisfactorily weeds. None of herbicide treatments could reduce Field binweed populations satisfactorily, so that the highest population reduction was observed in Lambs quarters (100%) where sprayed with Metribuzin. Percent total weed density reduction by pyridate and Isoxaflutole was highest (78% and 57%). Metribuzin reduced total weed density by at least 71%. Hand weeding plus cultivation, Pyridate plus inter-row cultivation and pyridate, caused chickpea grain yield to increase by 44.83%, 44.46%, 40.58% respectively compared with weedy check. Isoxaflutole plus inter-row cultivation and Isoxaflutole caused chickpea grain yield to increase 37.18% and 34% respectively. The highest chickpea phytotoxicity (30%) was achieved where Linuron applied. Conclusion Overall results showed that pyridate at rate 1.5 kg a.i./ha is a suitable option for control of weeds and increasing the chickpea grain yield. The results also showed that inter-row cultivation had no significant effect on weed reduction and grain yield by pyridate and Isoxaflutole. In this study, isoxaflotle controlled a wide range of weeds. It is suggested that further studies be carried out on the use of this herbicide at different times of application (pre emergence and post emergence) and different amounts.

Introduction There are many different factors that affect yield and quality of agricultural crops, including weed management. The abundance, distribution, density and composition of weed species in a cropped field varies due to the nature of the crop, cultural practices and cropping pattern/system, soil type, moisture availability, location and season, therefore identification of weed flora is important to identify the proper weed control options and enables farmers to use the best management strategies. Common Bean (Phaseolus vulgaris L.) is an increasingly important cash crop for growers in western provinces of Iran. Due to the lack of basic information about the weed diversity in common bean fields in Lorestan province which is the mean producer of bean in Iran), the current study was conducted for exact identification of flora condition of weeds. Materials & Methods The present investigation was carried out to find out weed floristic composition in common bean fields of Azna (33°45΄ N latitude, 49°45΄ E longitude, with a mean altitude of 1871 m above sea level), in the North of Lorestan province during 2014. In this study, 34 fields of bean using method of stratified random-sampling, and by assigning the suitable number of the samples for each level, were selected. The longitude and latitude and sea level of different fields were recorded exactly by global positioning system (GPS). In order to determine the density and composition of weeds, sampling in each field done using the pattern of W. According to the pattern of the W, 9 points in each field were selected and the distance between two sampling points was 20 meters and in each point by using a 0.5 m × 0.5m quadrate the density and composition of weed species was determined. For data analysis of weed flora in the fields, frequency, abundance index, distribution uniformity and mean density were calculated using appropriate equations. Weed frequency indicates the proportion of fields where the species was found. The diversity of weed species was described by species richness and weed density was determined by counting the number of plants in each sampling quadrate. Cluster analysis was done by JMP software using the data related to species richness index, species diversity and similarity. Results & Discussion In the current experiment, 23 weed species from 14 families were collected and identified at the different bean fields in the studied region. The highest number of weed species belongs to Poaceae family (five species) and Asteraceae family (three species). Based on results, 78% and 22% of weed species were dicotyledonous and monocotyledon respectively. Among the identified weed about 65% were annual and the remaining species were biennial or perennial. It seems that intensive and high input cultivation of common bean in the studied region affected the composition and diversity and density of weeds. Previous studies also showed that perennial weed communities under less cultivation and reduced tillage systems are often more frequent whearase in conventional systems the annual weed are dominant. Kenaf (Hibiscus cannabinus L.), Field Bindweed (Convolvulus arvensis) and Redroot Pigweed (Amaranthus retroflexus L.) had the highest and Black Nightshade (Solanum nigrum L.) and Goat's Beard (Tragopogon pratensis L.) had the lowest density, uniformity and abundance in the common bean fields. The density of the weed species varied considerably in the different fields and the maximum density of weed (5.5 plants. m2) in the fields was recorded for Hibiscus trionum. The most important noxious weed of studied regions were Field Bindweed (Convolvulus arvensis), (Sorghum halepense (L.) Pers.)، (Cynodon dactylon (L.) Pers.) and (Echinochloa crus-galli (L.) Beauv.). The highest value of species richness index (27.5) and Simpsons diversity index (0.94) were recorded for Southwest, whereas the lowest value of species richness index (17.14) and Simpsons diversity index (0.86) calculated for Southeast regions. Results of another study showed that species richness is related to geographical condition and increase with the height. Decrease of species richness in plain areas suggests that agronomic management has a strong effect on species diversity and weed abundance during the time. Conclusion The occurrence of numerous weed species in bean fields means that different methods of weed control must be selected because some of these weeds such as redroot pigweed (Amaranthus retroflexus L.) can produce a lot of small seed which may increase the problem of weeds in further years. The higher number of dicotyledonous weeds means that special cautions for the use of chemical herbicides is necessary because many of recommended herbicides for broadleaf weeds could result in serious damages to the common bean fields. It seems that in these conditions considering the integrated weed management (IWM) methods is justified.

Introduction Mungbean [Vigna radiata (L.)Wilczek] is the most important source of protein in south and southeast Asia. This plant, have the most important sources of protein in arid and semiarid regions and played a major role in the economy of the regions. Seed mung bean has 51% carbohydrate, 26% protein, 10% moisture, 4% mineral and 3% vitamin. This crop can be successfully grown on marginal lands where other crops perform poorly. Legumes, have mainly poor competition against weeds. Yield decrease in crops due to the presence of weed, depending on the area and specific weed species its area. Raman & Krishnamoorthy (2005) reported that mungbean yield decreased in infested treatment to weeds to 35 percent. Optimum plant population density is an important factor to realize the potential yields as it directly affects plant growth and development. The sowing rate of 20 kg h-1 usually recommended for small to medium seed varieties might be too low to obtain optimal yield. Barary et al. (2002) observed the effect of row and plant spacing on seed yield but it was not significant. Among the yield components, number of pods plant-1 and number of grains pod-1 and 1000 seed weight decreased with increasing seed rate. Determining the optimum plant density is very important to obtain maximum quantity and quality of economic yield. Reports show that the suitable density range of mung bean depends on the distance between plants. This study was conducted to investigate the effect of density on the morpho-physiologic traits and seed yield of the mung bean and to determine the optimum planting density on weed management in the Khorramabad. Materials & Methods Field experiments were conducted at Lorestan Agricultural and Natural Resources Research Center, Khorramabad, Iran (48.36° E, 33.48° N, altitude), 1,125 m above the sea level with annual average precipitation and temperature of 471.5 mm and 17.7 C˚, respectively. The fields were in fallow in the preceding year of the experiments. The soil at the test sites were a clay-silt with a pH of 7.7 and organic matter of 1.0% in 2014. Prato cultivar has a 1000-seed weight of approximately 25 g. Layout system was randomized complete block design (RCBD) with factorial arrangements, with 8 treatments in 3 replications. Weed factor with two levels (controlled and uncontrolled) and seed rate per unit area (25, 50, 75 and 100 kg. h-1) equivalent (6, 12, 18 and 24 plant m-2) was calculated for each plot. In this experiment, after sowing mapping, evaluated treatments were randomly assigned to experimental plots and any density considered on the 6 lines with 6 meters length, rows spacing of 60 cm and 5 cm sowing depth. Seeds planting was done by hand in June 12, 2014. Irrigation was done immediately after planting. Due to climatic conditions, farm irrigation was carried out flooding until the end of the growing season (every 10 days). In the plots of interference treatment no operations performed against the weed control. Assessing the density and weeds biomass were randomly at flowering time of crop with samples of the two frame 0.5× 0.5m per plot. Density and dry matter of weeds were counted and measured. At the end of the growing season after physiological maturity with marginal effects deletion (half a meter from the beginning and end of each row) area of 6 m-2 from 4 central rows of each plot was measured to estimate biomass, yield and seed yield by 14% seed moisture. Determining of morphological traits and yield components was selected 10 plants from each plot at final harvest. The traits measured, including biological and seed yield, plant density, pod number per plant, seed number per plant and seed weight per plant. Analysis was done by analysis variance and by using SAS 9.1. For comparing regression coefficient and latitude of origin two treatments consisting weed free and weed infested in level of seed amount was used. Results & Discussion The experimental maximum yield (2011 kg. h-1) was achieved for weed control treatment with crop density of 25 kg. h-1, while, the lowest yield (672.7 kg. h-1) was related to weedy plots with crop density of 100 kg. h-1. The study revealed that crop density of 25 kg. h-1 mung bean (Vigna radiate) (equivalent to 60 plant. m-2) is optimum to obtain maximum mung‌ bean yield. Results also indicated mung‌ bean yield increased by 82.7 by weed control, the importance of weed interference in reducing mung‌ bean yield and necessity of weed control to achieve higher yields. Among the yield components, number of pods plant-1 and number of grains pod-1 and 1000 seed weight decreased with increasing seeding rate. It seems that seeding rate of 25 kg.h-1 reduced mung bean density in area unit, and increased weed growth probably due to abundance of resources. However, seed rate of 100 kg. h-1, the Conclusion Generally, the results of this research showed that selecting mung bean varieties with runner type and optimum density performance used against weeds can increase competitive pressure. Weeds management by weeding out, not only makes more seed yield but also prevented environmental damage and will help environmental sustainability.

Effects of different periods of weed control in paddy rice (Oryza sativa L.) were studied in Veysian region of Lorestan province in 2004. The experiment was conducted in a randomized complete block design with four replications and 10 treatments of hand weeding in two series included weed free and weed infested plot up to 14, 28, 42 and 56 days after transplanting, plus weed free and weed infested control. Based on 5 and 10% acceptable yield loses, the critical periods were between 11 to 40 and 14 to 30 days after transplantation, respectively. Weed competition before and/or after these critical periods had negligible effects on grain yield of rice. This period, based on growing degree days (GDD) was 198-768 GDD for 5% acceptable yield loss. Increasing periods of weed interference in the early stage of the crop resulted in a steady decline in grain yield. Yield losses equivalent to 47 kg/ha of grain resulted for each day that weed control was delayed between 14 and 28 days after transplanting.