فصلنامه مطالعات حفاظت گیاهان
سال سی و ششم شماره 2 (تابستان 1401)

 Every year, soli-borne pathogens of beans cause a lot of damage to this crop. Caudex and root rot of beans caused by Macrophomina phaseolina, Rhizoctonia solani, and Fusarium solani are among the most common diseases of this plant. Cultivating resistant species and maintaining shifting cultivation are among the most effective methods of controlling this disease Disease caused by Rhizoctonia solani include seedling death and in some cases cause rot of aerial parts. Macrophomina phaseolina is a plant-borne pathogen that has a wide range of hosts and causes extensive damage to farmers around the world each year. This fungus is a polyphage and causes disease in more than 500 different plant species such as soybeans, peas, pines, kiwis, cotton and sesame, peanuts, cotton, sunflower, melon. Fusarium solani f.sp. phaseoli Burk, is a fungus isolated from peas and red beans, it is present in most soils and causes disease on legumes and plants that grow in hot and humid conditions.

 A factorial experiment in the form of Completely Randomized Design is conducted in order to evaluate the resistance level of beans species to these fungi. The factors consisted of species (five levels, containing Sadri, Shazand, Saleh, Dorsa, and Goli species) and fungi species (8 levels: each of three fungi alone, combined with each other, and a control sample without any fungus). The reaction of beans species was by calculating the severity of disease and evaluating dry and fresh weight of aerial organs and root and height of the bushes. Steps to perform the test: 1- Preparation of seedbed for planting and sowing seeds of bean cultivars 2- Planting seeds and start growing seedlings 3- Inoculation of seedlings 4- Determining the severity of the disease 5- Measuring the height of aerial parts of seedling.

 Plants are equipped with several defense mechanisms to resist the attack of various pathogens. These include pre-existing structural or biochemical defenses that prevent pathogens from invading, or a series of induced structural and biochemical defenses after an attack. In natural ecosystems, most of the existing pathogenic models are the result of long-term evolution of both the host and the pathogen, and there is usually a high genetic diversity between plants and microbial populations. Today, with the widespread cultivation of cultivars with a uniform genetic background, it has led to the increasing development of susceptible strains of pathogens and the occurrence of widespread epidemics of plant diseases. Therefore, there is a great need to produce lasting resistance to pathogens in plants. Rhizoctonia solani, Macrophomina phasolina and Fusarium solani are fungi with widespread global damage to crops. Therefore, strategies to reduce the quantitative and qualitative damage of these fungi should be studied. In this study, it was observed that beans infected with Macrophomina phasolina, the first symptoms after about four weeks, were yellowing of leaves, wilting of the plant and discoloration of root vascular tissue to reddish-black brown. Also, plants infected with Fusarium solani and Rhizoctonia solani turned the root skin brown. With the spread of disease-causing fungi, necrosis of the crown and roots of tissues was observed. In this case, the color of the vessels changed and turned yellow to brown. Restriction of root development, slow growth of plant shoots, symptoms of leaf yellowing and paleness similar to the symptoms of nutrient deficiency and wilting and leaf fall were the obvious symptoms of these diseases. The results of this study showed that Sadri and Darsa cultivars had relative resistance to all three fungi alone, but Sadri cultivar also showed relative resistance to binary combinations of fungi. But none of the cultivars used were resistant to all three fungi. The experimented species reacted differently to the pathogenic fungi. The maximum and minimum severity of the disease was observed in Goli and Sadri species respectively. The maximum height of seedling was observed in Sadri and Shazand species infected with R. solani and M. phaseolina pathogenic fungi and the combination of these two fungi with Shazand. The maximum dry and fresh weight of aerial organs and roots of infected seedlings was observed in Sadri species infected with F. solani fungus.

The research results indicated that Sadri species, with minimum severity of disease and maximum height and fresh and dry weight of aerial organs and root, was the most resistant species to all three fungi solely and combined.

One of the most important problems facing modern agriculture is soil born plant pathogens control, especially root-knot nematodes. Chemical control, crop rotation and using resistance cultivar are common methods in control of most plant pathogens; however, there are low efficacy in control of root-knot nematodes regarding host wide range, long-term survival ability in soil and plant residual even in absence of host. One of the new methods in the management of root-knot nematodes is resistance induction in host using chemical compounds and microorganisms.  In this method there are not any side effect. The aim of this study was to investigate the effectiveness and mechanisms involved in induced resistance by three chemical compounds (Hexanoic acid, Thiamin and Riboflavin) accompanied by Trichoderma harzianum BI in tomato plants against Meloidogyne javanica. The objectives of this study were addressed by monitoring the activity of peroxidase, polyphenol oxidase, catalase, phenylalanine ammonia lyase, accumulation of total phenolic compounds and nematode disease indexes.

This study was conducted in the Faculty of Agriculture, Ferdowsi University of Mashhad and was performed with susceptible cultivar to root knot nematode (Early Urbana). 2-4 leaf stage tomato seedlings were transferred to 3 Liter pots filled with 2 liter sterile soil and maintained under greenhouse condition to the end of experiment. 2000 Meloidogyne javanica J2 larvae (N) were added to each pot. Tomato plants were treated with Trichoderma harzianum BI (TH) with a population of 1×107 spores/mL, Hexanoic acid (HX), thiamine (TI) and riboflavin (RB) with a concentration of 20 mM. Distilled water was used as control treatment. Sampling was performed at specific time points from each pot and the samples were transferred to the laboratory. Enzyme extract was extracted from tomato roots to assay the Peroxidase (POD), Poly phenol oxidase (PPO), Catalase (PAL) and Phenylalanine ammonia lyase (PAL) enzyme activity. Also total phenol content and nematode pathogenicity indexes were measured at the end of the growing season.

 Based on the results, the highest POD and PPO enzyme activities were measured in TH + HX + N, TH + RB + N and TH + TI + N treatments, respectively, at a time point of 72 hours after treatment. The highest CAT enzyme activity was also recorded in the treatments TH + HX + N, TH + RB + N and TH + TI + N, respectively, at 96 hours after treatment application, the highest PAL enzyme activity was recorded in TH + HX + N, TH + RB + N and TH + TI + N treatments, respectively, at a time point of 120 hours after treatment. The highest total phenol content of roots  were measured, respectively,  in TH + RB + N, TH + HX + N and TH + TI + N treatments with values of 125.33, 114.67 and 109.33 mg gallic acid per gram roots. Also, nematode pathogenicity indexes including gall index, number of egg sacs and number of eggs in each egg sac were measured 45 days after the start of the experiment and a significant difference was observed in all treatments compared to the control treatment. The lowest values of pathogenicity indices were recorded in TH + HX + N, TH + RB + N and TH + TI + N treatments, respectively. Systemic resistance in plants can be induced with biotic and abiotic agents. The effects of chemical and microorganisms on plants resistance induction were investigated in many studies. However, effect of these agents on plant parasitic nematodes were considered less than other pathogens. Capability of different Trichoderma isolates on nematodes damage reduction are reported in many different studies. Several biocontrol mechanisms are reported for Trichoderma. As biocontrol ability of an isolate can be different mechanisms consequence. Effect of different chemical such as Hexanoic Acid, Thiamin and Riboflavin on plant disease have been investigated, however, there are little known about the effects of these chemicals on plant parasitic nematodes. The use of these chemicals as an enhancer of plant resistance to pathogens, due to their low risk to humans and the environment has been increasingly welcomed by researchers.

The results showed significant effect of used treatments on the reduction of root-knot nematode damage in tomato plants. These results justify further studies to investigate and identify the mechanisms of these compounds mode of action on increasing host resistance against this pathogen.

 One of the most important diseases of cucumber is cucumber stem and root rot by agent Fusarium oxysporum f.sp. radicis-cucumerinum. The use of resistance inducers, which on the one hand activate the plant's defense mechanisms before confronting the pathogen and on the other hand do not pose environmental risks, has been considered by researchers in recent years. Recently, the use of sodium silicate as a potential activator of acquired resistance is being developed. Sodium silicate plays an important role not only in systemic acquired resistance but also in the expression of genetic resistance and stimulates the production of pathogen-related proteins (markers of systemic acquired resistance). The use of sodium silicate increases the tolerance of plants to environmental stresses and increases the quality and quantity of agricultural products. Hence it modulates the time and amount of plant defense responses and acts as a secondary messenger in induced systemic resistance.The effect of sodium silicate was investigated in order to induce defense reactions in cucumber cultivars and control the disease.

First, different concentrations of sodium silicate were applied on the growth of the pathogen in the laboratory. The effect of different concentrations of sodium silicate on pathogen growth was tested by mixing with culture medium. Different concentrations of sodium silicate (1, 2, 4 mM) are each combined in 100 ml of PDA culture medium and poured into 9 cm culture dishes. The percentage of sodium silicate inhibition on fungi is calculated according to the following formula: N = A-B / A. The effects of different concentrations of sodium silicate were applied in the soil on cucumber in the greenhouse. At time intervals of 0, 48, 72 and 96 hours after inoculation with pathogen, sampling of treated seedlings was performed to measure secondary metabolites and enzymatic activity. Disease severity, growth factors, production of secondary metabolites and activity of defense enzymes in cucumber plant and thus disease control were evaluated. Disease severity and growth factors were studied in a completely randomized design and Biochemical factors in a completely randomized design with factorial arrangement in which the main factors are the applied treatments and the sub-factors are the sampling times with three replications.

Sodium silicate showed a direct antifungal effect on fungal growth after 5 days and by increasing its concentration up to 4 mM caused a significant increase in antifungal effects. A significant decrease in colony diameter compared to the control was observed only at concentrations of 2 and 4 mM . This effect was observed as termination the growth of fungi at 72 hours after cultivation of fungi in culture medium containing sodium silicate. This effect remained stable with increasing incubation time. Fusarium fungi are root pathogens and reduce the absorption of water and minerals and clog the vessels, thus directly affecting the growth parameters in the roots and green parts of the plant. Infected control compared to healthy control showed a significant decrease in all growth parameters measured. Disease severity and growth factors were significantly affected by the effects of sodium silicate at a probability level of 1%. Application of sodium silicate in all concentrations had favorable results in significantly reducing the symptoms of the disease. Application of sodium silicate in diseased plants improved growth parameters. The mean value of growth parameters in different treatments and their treatment grouping based on LSD test is done at 5% probability level. Based on the results of this study, a decrease in chlorophyll and carotenoids and an increase in phenolic compounds and antioxidant enzymes and proline were observed in infected control plants compared to healthy controls. In this study, in the presence of sodium silicate in diseased plants, the amounts of pigments, phenol, flavonoids, anthocyanins, proline, protein and the activity of oxidative enzymes were significantly increased compared to the infected control.

According to the results, sodium silicate had direct antifungal effects in culture medium. In addition, a reduction in disease severity was observed in plants treated with sodium silicate in the greenhouse. Sodium silicate can be used as a chemical stimulant of plant defense and plant growth enhancer, for effective protection of cucumber plant against disease. Therefore, induction of resistance has found its place as a new technology for controlling plant diseases and its effect has been proven in laboratories and some farms.

Chemical fungicides are widely used as effective control agents on a great diversity of fungal plant diseases. However, their excessive use, causes environmental pollution and health problems. Biological control as an environmentally friendly method can be a good alternative for chemical fungicides. Trichoderma is one of the antagonistic fungi with rapid adaptation to a wide variety of habitats. Trichoderma harzianum is a powerful agent for biocontrol of plant pathogens. It also can be used as a plant growth stimulant. However, its efficacy can be affected by biotic and abiotic factors, and encapsulation has been used to maximize its efficacy. Encapsulation process provides a protective barrier around the biocontrol agent, so the harmful external factors such as pH, humidity, and ultraviolet radiation do not damage its action. Encapsulation of the bioactive agents has been developed in recent years as a new potential tool for ecological and sustainable plant production. Encapsulation in biopolymer matrices has been recognized as an effective method for controlled release of a bioactive agent used for plant protection. Chitosan, the deacetylated derivative of chitin polysaccharide is one of the most important biopolymers that is widely used in biological and medical sciences especially for encapsulating essential oils and extracts due to its biocompatibility, low toxicity and biodegradability into safe byproducts. In this study, antifungal effects of nano capsulated Trichoderma extract (NCTE) and Trichoderma extract (TE) against Macrophomina phaseolina have been investigated.

 The nanocapsules were prepared by ionic gelation method. This is one of the most advantageous techniques for the production of nanocapsules. This technique is easy to perform and avoids the use of organic solvents. The biocompatible and biodegradable polymer, chitosan, was used as a capsule coating agent. After extraction of T. harzianum secondary metabolites, encapsulation process was carried out. Tripolyphosphate was used as cross-linking agent in the encapsulation process. The surface morphology of the nanoparticles was considered using Field Emission Scanning Electron Microscopy (FE-SEM). The mean particle sizes of the prepared nanoparticles were measured by Dynamic Light Scattering (DLS) technique. For consideration of the antifungal effects of nano encapsulated Trichoderma extract (NCTE) and Trichoderma extract (TE) against Macrophomina phaseolina, strile potato dextrose agar (PDA) containing different concentrations of NCTE and TE were prepared. After 5 days, colony diameter of the pathogen was measured in all treatments. The inhibitory effect was calculated compared with the control. Data were statistically analyzed by SAS software.

 The obtained results indicated that the prepared nanoparticles were spherical in shape and the average size was equal to 77.91 nm with poly dispersity index (PDI) 0.23554. PDI value indicated the physical stability of the nanoparticles and prevented aggregation of the particles. Antifungal effects of NCTE and TE were observed in all treatments, however nanocapsules contains Trichoderma extract were more effective than Trichoderma extract. In each treatment containing TE and NCTE, maximum inhibitory effect was related to concenteration of 30 percent. In consideration of ihibition percent of NCTE and TE on M. phaseolina within 5 days, it was found that on the first and second days, inhibitory effect of TE was more than NCTE. However, on the third, fourth and fifth days, there were no statistically significant difference between treatments in TE while in NCTE, a significant increasing was observed. The reason for the high inhibition percent in TE treatment in the first and second days was related to rapid release of active ingredients in the culture medium and the passage of time had no effect on improving its yield. According to the results in this research, it can be concluded that chitosan nanoparticles will be a good carrier for Trichoderma extract encapsulation. It also improves their antifungal activity against M. phaseolina.

Nano-encapsulation of the bioactive compounds enhances physical stability, protects them from oxidation process, controlling their release, improves water dispersion of hydrophobic compounds and enhances their bioactivity efficacy. In this study, nano encapsulation of Trichoderma extract, increased its antifungal effects over time. Nano encapsulated particles containing antagonistic fungi were able to control the pathogenic fungus more effectively and in a longer period of time due to the controlled release of the fungal extract. Results showed that antifungal efficiency of T. harzianum was increased by nano encapsulation procedure. Since chitosan is a biodegradable polymer without any harms for safety, this technique can be suggested as a good candidate for biological control. Our future investigations are directed to test nanocapsules simultaneously loaded with biological agents on M. phaseolina under greenhouse and field conditions.

Noctuidae species are herbivores as caterpillars and some of them are most destructive crop pests. Moreover, they role as pollinators and prey in ecosystem. Early researches on Noctuidae of Iran were published more than 150 years ago. In recent two decades, Iranian researchers investigated the Noctuidae fauna of Iran and published several articles on different subfamilies. The subfamily Xyleninae may be paraphyletic and defined by plesiomorphic character states. Xyleninae in classic taxonomy is defined by the valva of male genitalia which is not as much constricted below the cucullus at the distal end of the clasper. The cuculus usually is expanded and bears a corona of stout setae. The ampulla is small and usually finger-like, except in Xylenina. Dorsal surface of saculus is usually irregular in direction to the base. Vesica is often short and tube-like or triangular with few basal cornuti and an elongated patch of spines on the apical half of the vesica. In female genitalia, the ductus bursae is short and heavily sclerotized; and the appendix bursae is small and inconspicuous or absent. It is worth mentioning that Lepidoptera species are one of the important elements of Zagros mountain ranges which dominated by oak forests. Their larvae are important leaf-eaters of oak plants. Therefore, the aim of this research was determining the moths’ fauna of Xyleninae subfamily belonging to Noctuidae in Zagros Mountains of Khuzestan and Ilam provinces. 

Numerous night samplings were done to study the fauna of Xyleninae subfamily (Lep.: Noctuidae) in Zagros Mountains in the provinces of Khuzestan and Ilam during 2018-2019. Sampling was performed by light traps powered by 12 volt batteries and 8 watt UVB light tubes. Sampling areas were two locations in Khuzestan province namely Imamzadeh Abdollah village in Baghmalek (31°22'24"N, 50°07'51"E, 1540 m and 31°23'10"N, 50°09'29"E, 2360 m) and Shelal village in Andika (32°16'19"N, 49°33'07"E, 1700 m and 32°19'10"N, 49°35'06"E, 1465 m) as well as two locations in Ilam province namely Kabir-Kouh in Abdanan (33°02'57"N, 47°18'04"E, 1215 m and 33°03'53"N, 47°18'40"E, 1730 m) and Protected Area of Manesht and Ghelarang (33°34'47"N, 46°33'52"E, 1455 m and 33°34'33"N, 46°36'15"E, 2215 m). The specimens and genitalia slides were deposited in the Insect and Mite Collection of Ahvaz (IMCA), Plant Protection Department, Shahid Chamran University of Ahvaz.

 A total of 28 species belonging to 19 genera of Xyleninae were collected and identified. Among them, 9 and 15 species were new to the fauna of Khuzestan and Ilam provinces, respectively. Furthermore, Dichonia pinkeri (Kobes, 1973) is newly recorded from the fauna of Iran. Notes on the bionomy and distribution of the collected species as well as diagnostic characters and illustrations of wing patterns and genitalia for the D. pinkeri were presented. According to the results, 9 species have not been recorded in the previous investigations in Khuzestan province. These species are as follows; Caradrina boursini, Hoplodrina ambigua, Polyphaenis monophaenis, Apamea syriaca fuscorhoda, Sesamia sp., Atethmia centrago, Evisa schawerdae, Leucochlaena muscosa, Pseudenargia deleta. 15 out of 17 collected species in Ilam were new for the fauna of this province. Because this province was less explored previously for Noctuidae fauna. This indicates that we are still far from a complete provincial list of the Noctuidae in Iran. It needs more samplings especially in area and times which less explored already and using different methods such as bait traps. We didn’t present the results on Agrochola species here and will treat them separately. 13 species were collected in both studied provinces, among which two species Hoplodrina ambigua and Polyphaenis monophaenis were new for the fauna of Khuzestan and Ilam. This implies that habitat of such species are Zagros areas including oak forest vegetations and their distribution range may be further expanded in Zagros range. Comparing to the results of Esfandiari et al. (2011) on the noctuid fauna of sugarcane plantations in Khuzestan province, only Spodoptera exigua and Caradrina clavipalpis out of their 9 Xyleninae species were recorded in the present study. This is because of semidesert climate in sugarcane farms which differs from climate and land cover of our sampling areas. It is necessary to investigate the noctuid fauna, complete the checklists and provide identification catalogues for Iran. Also, larval stages and food plants must be studied in each area. Furthermore, we need local taxonomic revisions in some groups.

The green peach aphid Myzus persicae (Sulzer) (Hemiptera: Aphididae) is one of the severe pests of bell pepper Capsicum annuum L. in the greenhouse. Ladybird, Hippodamia variegata (Goeze), is an important general predator in both larval and adult stages to various aphid species, including, M. persicae. In this study, the effect of nutritional interaction among plant-herbivore-natural enemy under the influence of foliar application of iron, zinc, copper and manganese in bell pepper on the activity of digestive enzymes of the third and fourth instar larvae of H. variegata fed on M. persicae was examined.

 The experiments were performed as a completely randomized design with four replicates per treatment during 2020-2021 in the greenhouse and laboratory of the Department of Plant Protection, College of Agriculture, Lorestan University. The foliar application of micronutrient carried out at four-to six-leaf stage with a certain amount of each micronutrient fertilizer. Then, sufficient number of the third and fourth instar larvae of H. variegata were randomly collected from each treatment and replication. The samples transferred to 1 mL of distilled water, and homogenized with a hand pestle. Then, the samples centrifuged at 13000 g for 15 min at 4°C. The supernatants as the enzyme source were collected and reserved at −20°C for starting biochemical assays. The activity of digestive enzymes was measured according to the standard protocols.

The results showed that the amount of digestive enzymes activity of the third and the fourth instar larvae of H. variegata fed on M. persicae reared on the different micronutrient treatments were higher than the control treatment. The total protease and the trypsin activity were higher in the third instar larvae H. variegata reared on manganese (0.583 and 19.296 U/mg protein) and iron (0.574 and 18.426 U/mg protein), respectively. The highest and lowest activity of chymotrypsin, aminopeptidase and carboxypeptidase were found in the third instar larvae in manganese (15.518, 8.95 and 7.536 U/mg protein) and control (7.353, 2.139 and 2.665 U/ mg protein) treatments, respectively. The highest (18.952) and lowest (9.139 U/ mg protein) elastase activity were found in the third instar larvae on iron and control, respectively. The higher activity of α-amylase (25.20 U/mg protein) was observed in the third instar larvae of H. variegata in iron treatments then the other treatments. The total protease (0.183 U/ mg protein) and the chymotrypsin (10.396 U/ mg protein) of the fourth instar larvae predatory had higher activities with iron treatment and these enzymes had lower activities on control (0.036 and 6.763 U/ mg protein) and copper (0.059 and 6.655 U/ mg protein) treatments. The highest activity of trypsin and aminopeptidase were observed in the fourth instar larvae of H. variegata fed on M. persicae reared on iron (6.893 and 2.317 U/ mg protein) and the highest activity of elastase was found on iron (2.486) and zinc (2.251 U/ mg protein, respectively). Also, the lowest activity of trypsin, aminopeptidase and elastase were found on control. The carboxypeptidase activity was higher in the fourth instar larvae H. variegata fed on the all micronutrients than the control. Also, the highest and lowest activity of α-amylase were observed in the fourth instar larvae H. variegata fed on micronutrients of copper and iron (17.64 and 15.04 U/ mg protein) and control (9.160 U/mg protein), respectively.Discussion The results showed that the amount of digestive enzymes activity of the third and the fourth instar larvae of H. variegata fed on M. persicae reared on different micronutrient treatments were higher than the control treatment. Based on the results, the foliar application of plants with micronutrient fertilizers has a positive effect on the performance of predator of H. variegata through nutritional interaction and improving of the growth quality. Thus, the quality of host plants, as the first level of nutrition, has an important effect on the physiological characteristics of the predator on the third level of nutrition and show the positive effect of prey nutrients on the physiological performance of H. variegata that can be used in M. persicae management programs.

Using different micronutrient fertilizers along with biological control agents such as ladybird H. variegata could be effective in integrated management programs of M. persicae through the growth quality improvement of the host plants.

 The idea of sustainable agriculture has been considered recently due to increasing knowledge and concerns about the destructive effects of chemical pesticides. Biological control is an ecologically based pest management strategy with an important role in achieving sustainable agriculture. The success of this beneficial method closely depends on taxonomy, since accurate identification of pests and their natural enemies has a great importance in biocontrol project’s achievement. The gall midges of the genus Feltiella are cosmopolitan species known as highly effective predators of tetranychid mites. Despite the high potential of Feltiella species as a biological control agent, F. acarisuga is the only species commercially available among eleven species of the genus. These predators are difficult to distinguish from each other because of the high similarity and low information about them. Comprehensive taxonomic studies are needed to identify promising species for the control of tetranychid mites. The aim of this study is to determine the status of the native Feltiella species in Iran emphasizing their molecular characteristics.

The native predatory gall midges larvae and pupae were collected periodically from the spider mites colony on various host plants (Urtica dioica, Lactuca scariola and Rubus sp.) in countrysides around Mashhad during 2018-2019 and maintained in a growth chamber (LD 16:8, 21±1°C, RH 75±5%) until emerging adults. Adults were preserved in ethanol for further analysis and identified morphologically based on male genitalia and other structures used in taxonomic treatments of the genus. The molecular genetic analysis was included DNA extraction using the Chelex 100 method, PCR amplification of the mitochondrial COI gene using the LCO/HCO universal primer pair, sequencing the gene, and matching the sequence with those of the related species using BLAST. Nucleotide divergence between sequences was estimated by Maximum Composite Likelihood model and by the Pairwise deletion method in MEGA-X software. Intra- and interspecific distances were calculated using ExcaliBAR software and their frequency distribution histogram was plotted using Excel software. The sequence data were analyzed through the neighbor-joining method using MEGA-X software. Evolutionary distances for the NJ method were computed by Kimura’s two-parameter distances. The resulting tree was subjected to bootstrap analysis with 1000 pseudoreplications. The cecidomyiid genus Endaphis was employed as an outgroup taxon to construct the phylogenetic tree.

Based on morphological studies, specimens of the native acarivorous gall midges from various localities in Mashhad were identified as Feltiella acarisuga Vallot. In spite of the morphological result, the DNA sequence of the native species was relatively different from the corresponding sequence of F. acarisuga available in GenBank. The sequence match between the two species was 92.74% in maximum. The match with F. acarivora sequences was also low (maximum 91.84%). Whereas the BLAST results of the indigenous species sequence matched the corresponding sequence of F. tetranychi with more than 99% homology. Comparing the nucleotide differences between the specimens of the present species with F. acarisuga and F. tetranychi also showed that our Feltiella is a distinct species from F. acarisuga, despite of morphological identification. In the histogram of nucleotide distances, intra and inter specific distances in the COI gene overlapped with each other which were related to the nucleotide distances between individuals of F. tetranychi species in the gene bank and individuals of the species collected in the present study. Based on the neighbor-joining tree inferred from partial sequences of the COI gene related to Feltiella species, Iranian indigenous species and F. tetranychi species were in the same ancestor, while individuals of F. acarisuga species were in separate ancestors from the native gall midges. Therefore, according to our molecular studies, the specimens of the native gall midges of Mashhad were F. tetranychi. The possible interpretation for the difference between morphological and molecular identification results in this study is the difficulty of distinguishing the two species from each other, due to their great morphological similarity. F. tetranychi has been mentioned as a possible synonym for F. acarisuga so far, because of the high morphological resemblance. Personal correspondence with international experts revealed that there are two taxa named F. tetranychi, one named by Rubsaamen and introduced as one of the synonymous names of F. acarisuga, and the other named by Kieffer which is an unknown species and mentioned as a possible synonym of F. acarisuga. To prove or disprove the hypothesis whether F. tetranychi is synonymous with F. acarisuga or completely separate from it, it is necessary to study voucher specimens of Feltiella species. Studying further populations of the gall midges on various hosts around the world through sequencing more than one molecular marker is also needed.

 In this study specimens of the native gall midges were identified as Feltiella acarisuga Vallot based on morphological identification, while molecular studies identified them as F. tetranychi. Since molecular identification is more accurate than morphological one, the present study can show how different the indigenous species is from the well-known commercial species F. acarisuga. The present native species probably has little ability to settle in artificial and manipulated environments despite of its activity in the nature of Mashhad. Its usage as a biological control agent for tetranychid mites requires further bio-ecological studies in the laboratory and its genetic comparison with known species in the world.

Cropping history can affect our knowledge about the compositions and diversity of weed communities in the soil. Weed Species composition and density are influenced by farming practices and vary from field to field and among areas within fields. Plants that escape control and produce seeds within the field can be considered as a major source of seed entering the soil. Crop rotation is an effective weed management tool which can change weed distribution pattern by increasing selection pressures. Two types of rotation including corn-winter wheat and fallow-winter wheat are the most common cropping systems in arid and semi-arid areas of Iran. The multiple tillage operations can affect the vertical distribution, germination and emergence of weed seeds in the soil. Weed seed bank density, species composition and diversity will change when crop management practices are altered.

A field experiment was conducted to evaluate the effects of corn-wheat and fallow-wheat crop rotations on weed seed bank dynamics and seedling population during 2016-2018 growing season at Shiraz University. The fields divided into 10 by 10 meter grids. Soil samples were taken from 0-15 and 15-30 cm depths by soil sampler (auger) with 10 cm diameter. These samples collected after seedbed preparation and before crop sowing from 144 points. The samples of each depth were mixed together, placed in black plastic bags, and transferred to the laboratory. Then, 250g of the total soil was weighed and separated. These samples was placed in silk bags and washed with low water pressure. Finally, weed seeds dried, identified and counted to the level of species using a binocular stereomicroscope. Those seeds that were resistant to forceps pressure assumed as healthy seeds. Weed seedling population were calculated using a quadrat before and after application of herbicide at the same points were seed bank was carried out. Geostatistics technique was used to investigate density and spatial distribution of weed seedlings in two different crop rotations.

The highest frequency of weed seed bank belongs to Portalaca oleracea, Amaranthus retroflexus, Chenopodium album and Lamium amplexicaule. Relative density of P. oleracea and A. retroflexus seeds increased in corn-wheat rotation compared with fallow-wheat. The results showed that weed seed frequency was significantly affected by crop rotation and depth of plowing. As corn-wheat rotation had 33% increasing and fallow-wheat 19.44% decreasing of weed seed in 15-30 cm soil depth. The size of the total weed seed bank in corn-wheat caused a greater seed accumulation in the surface layer of the soil (0-15 cm). Weed seed density in corn-wheat rotation increased 89.79% and 62.85% in 0-15 and 15-30 cm, respectively during two years. Shannon diversity index increased by 12% in corn-wheat and decreased by 5.4% in fallow-wheat compared with the first year. Margalf index of corn-wheat rotation at 0-15 and 15-30 cm of soil depths decreased 33.70% and 38.25%, respectively, compared to the fallow-wheat rotation in the first year. Sorenson similarity index of corn-wheat and fallow-wheat at 0-15 and 15-30 soil depths was 0.82% and 0.80% during two years. The slope of linear regression also indicates that fallow-wheat weed seed bank (0.79) decreased more than corn-wheat rotation (0.47). Spatial distribution of weed seedlings showed that there is a large similarity in distribution patterns of total weed population between before and after herbicide application in two different rotations during the second year. However, distribution pattern of seedlings in corn-wheat rotation at the first year herbicide application was different after application of herbicide. Therefore, herbicide application can affect spatial distribution and number of weed seedling species.

Corn-wheat rotation as a high input level cropping system with deep tillage increases the size of the weed seed bank, especially in the soil surface layer (0-15 cm). While fallow-wheat rotation as a low input level cropping system causes a decreasing in weed seed bank dynamics, increasing in the diversity and richness of the seed bank and improving the soil structure by wheat residual on the soil during fallow system. The results of this study will be valuable in aiding the prediction of likely weed infestations in rotation systems. This ability to predict the size of weed seed bank, pouplation, diversity and emergence would also provide valuable input to population dynamics models that can be used in weed management.

 Broomrape (Phelipanche aegyptiaca) is one of the most important plant parasitic species which causes significant yield loss of different crops by colonizing roots and uptaking nutrients from the host plants. Haustoria attachment stage is the most important stage to study molecular mechanism of plant-parasite interaction. Identifying key genes in haustoria attachment stage may reveal novel strategies to control Broomrape. Transcriptome studies by Next-generation (high throughput, deep) sequencing have become an important tool in the molecular biology of plants in recent years. All stage-specific RNA-seq data are available on the plant parasite genome project database (http://ppgp.huck.psu.edu). Differential gene expression in haustoria attachment stage can detect candidate parasitism genes and contribute to understanding molecular basis of plant-parasite interaction. This information may reveal novel genetic strategies such as HIGS to control Phelipanche aegyptiaca efficiently.

Analysis of Transcriptome data from the plant parasite genome project database (http://ppgp.huck.psu.edu) at Haustoria attachment stage and imbibed seed stage  revealed 391 gene transcripts with differential expression in these stages (unpublished data). Among these transcripts, four transcripts with unknown functions were detected with a high fold change in expression in the haustoria attachment stage. In order to predict possible roles of these transcripts in broomrape-host interactions, we used genome walking method to extend these transcripts. DNA was extracted from Phelipanche aegyptiaca stem using CTAB method. The quantity and quality of DNA samples were determined using the NanoDrop and agarose gel electrophoresis. DNA was digested by four restriction enzymes, DraI, EcoRV, StuI, PvuII. Four DNA libraries were purified using SDS protocol and ligated to GenomeWalker Adaptor (GenomeWalker Adaptor 1 and GenomeWalker Adaptor 2). Gene specific primers (GSPs) were designed using Primer3plus for Oa548, Oa3391, Oa1635, Oa424 transcripts. Primary PCR was done using gene-specific primer 1 (GSP1) and adaptor primer 1 (AP1). 1 µl of each primary PCR were diluted into 49 µl of deionized water. Diluted primary PCR products were used as template for Secondary PCR. Primary PCR was done to amplify the unknown sequence using gene-specific primer 2 (GSP2) and adaptor primer 2 (AP2). Secondary PCRs desired bands were extracted form agarose gel using Genet Bio k-8000 kit. Extracted products were ligated to pTG19-T vector. Recombinant vectors were cloned to Escherichia coli competent cells using heat shock procedure and then cultured on LB plates. Colonies that contain recombinant vectors were detected using blue-white screening. Colony PCR was done to confirm the presence of inserted sequences. Selected colonies were incubated in 37C in LB media containing 100 microgram per ml Ampicillin. Plasmid extraction was done by Silica procedure. After sequencing by M13F and M13R, complete sequences were assembled using CAP contig assembly software. Fgenesh online software was used to predict gene structure by selecting Arabidopsis thaliana as organism. Gene prediction was done by AUGUSTUS. Complete sequences were more analyzed using Blast, CDD, Phobius prediction, HMMER, InterProScan.

In this study we successfully extended the genomic sequences for two candidate transcript that showed increase expression in attachment stage. The sequence of Oa1635 and Oa424 transcripts was extended from the end of the 5`using the genome-walking method to determining the DNA sequence of unknown flank genomic regions and study the role of these sequences in plant-parasite interaction. Using this technique, 587bp and 165bp of new DNA sequences were obtained for Oa424 and Oa163, respectively. Analysis of homology using BLASTX algorithm for Oa424 showed 71.57% similarity (e-value: 2e-41) with unknown protein (XP_011081407.1) containing the transposase domain. Also, the results of CDD tool predicted the DDE_Tnp_ISL3 domain in position between 257 and 466 bp (e-value: 7.31e-14). For Oa1635 transcript, the results of homology analysis using BLASTX algorithm showed 72.73% (2e-9) similarity with retrovirus-related polyprotein sequence from transposon tnt 1-94 (GFP84907.1). As the regulatory function of proteins with mutant-like transposase domains, the two transcripts Oa424 and Oa1635 may play a key role in haustoria development and plant-parasitic interaction. Signal peptides have observed in these sequences suggesting that these transcripts encodes secretory proteins from haustoria to plant-parasite interaction.

Bioinformatics analysis on extended sequence, identified transposase domains which may have regularity role in parasitic process such as haustoria development or penetration. These genes may play important roles in plant-parasite interaction and developing molecular strategies to control this parasitic plant.

Integrated weed control in medicinal plants is one of the most important components of sustainable production. The dill seed production could be affected mainly by weed interference because of low competitive ability of this medicinal plant against weeds. So, this study was conducted in order to evaluate the effect of different doses of trifluralin in integration with non-chemical weed control options including living mulch, straw mulch and one time hand weeding on weeds, yield components, grain and essential oil production of dill.

 The study was conducted in Research Field of Agriculture-Jahad in Khoda Afarin County in East Azarbaijan Iran in 2019 as factorial experiment based on randomized complete block design with three replications. The first factor was application of different rates of trifluralin at four levels including 0, 480, 720 and 960 g ai ha-1 of trifluralin herbicide and the second factor was different levels of non-chemical weed control consisted of planting the living mulch of fenugreek (Trigonella foenum-graecum L.), planting the living mulch of bitter vetch (Vicia ervilla L.), application of wheat straw mulch, one time hand weeding 50 days after emergence of dill and control (without non-chemical weed control). Also the weed-free treatment during whole growth season was considered in the experiment.

The results indicated that the interaction effect of herbicide dose × non-chemical weed control method was significant (p ≤ 0.01) on weed density and biomass. At all non-chemical control levels, increasing the trifluralin dose reduced the weed density and the lowest weed density (2.33 Plant m-2) was observed in one time hand weeding and straw mulch treatments. The weed density at all non-chemical control levels decreased compared with that in without non-chemical control. Increasing the trifluralin dose decreased the weed biomass at all non-chemical control levels, and the lowest weed biomass was observed in one time hand weeding treatment + 960 g ai ha-1 of trifluralin (78 g m-2) that caused 86% reduction in weed biomass compared with control treatment. At all non-chemical control levels, the weed biomass decreased compared with that in without non-chemical control. Comparison of weed biomass among the different mulch treatments indicated that except in control (0 g ai ha-1 of trifluralin), the weed biomasses were not significantly different under all herbicide doses. The effect of non-chemical control level was significant on plant height, number of umbels per plant and 1000-grain weight of dill. The means comparison indicated that among the non-chemical weed control treatments the greatest plant height (97 cm), number of umbels per plant (31.8) and 1000-grain weight (192.8 g) were obtained in wheat straw mulch application. Also increasing the herbicide dose, improved the number of umbels per plant and 1000-grain weight of dill as the highest values were observed in 960 g ai ha-1 of trifluralin. The interaction effect of herbicide dose × non-chemical weed control method was significant on grain number per plant and grain yield of dill. At all non-chemical control levels, the grain number per plant enhanced by increasing the trifluralin dose. Comparing the non-chemical control treatment showed that the highest grain number per plant was observed in straw mulch application treatment and other non-chemical weed control treatments were not significantly different. The all non-chemical weed control treatments increased the grain number per plant compared with that in control treatment. By increasing the trifluralin dose under all non-chemical control treatments the grain yield of dill enhanced. Also the grain yield increased significantly at all non-chemical control treatments compared with those in without non-chemical control and the greatest grain yield of dill was observed in straw mulch application treatment + 960 g ai ha-1 of trifluralin (9842 kg ha-1) that indicated 6% reduction compared with weed free treatment. Also the grain yield in this treatment increased by 89.7% compared with that in without control and 0 g ai ha-1 of trifluralin (weed-infested treatment). The grain yield of dill in one time hand weeding treatment was higher than those in fenugreek and bitter vetch living mulch treatments. Also in living mulch treatments there were no significant difference between dill grain yield of 480 and 720 g ai ha-1 of trifluralin. The effects of herbicide dose and non-chemical weed control treatment were significant on essential oil content and yield of dill. The essential oil content and yield increased by increasing the herbicide dose and the highest essential oil content (1.46%) and yield (110.34 kg ha-1) were observed in 960 g ai ha-1 of trifluralin. The essential oil content and yield incresead at all non-chemical control treatments compared with that in without control treatment. The highest essential oil content (1.38%) was obtained in straw mulch treatment that was not significantly different with that in one time hand weeding (1.35%) treatment. The highest essential oil yield (100.6 kg ha-1) was obtained in straw mulc treatment that was not significantly different with that in one time hand weeding (96.43 kg ha-1).

 The all non-chemical weed control treatments decreased the weed density and biomass but the hand weeding and straw mulch treatments showed higher efficacy in weed biomass reduction compared with living mulch treatments (fenugreek and bitter vetch). The grain and essential oil production of dill in straw mulch and one time hand weeding treatments were greater than those in fenugreek and bitter vetch living mulch treatments. Therefore, the straw mulch and one time hand weeding could be recommended in integration with reduced doses of trfluralin for sustainable weed management of dill.

Rapeseed is one of the most important crops cultivated for oil extraction and has the highest annual growth rate (in terms of production) among the essential oilseeds in the world. Due to its slow growth rate, the rapeseed plant has little competitive ability against weeds in the early growing season, which causes it to be severely damaged by weed interference. Since the long-term presence of weeds in rapeseed could reduce its quality and yield, early weed control is essential to achieve economically acceptable yields.

In order to control broadleaf weeds in rapeseed fields, a factorial experiment based on a randomized complete block design with three replications was conducted in winter 2019 in Benvar Nazer region, Andimeshk county, Iran. The experimental factors included two types of rapeseed hybrids (Hayola 50 and Agamax) and clopyralid herbicide (1.5 L ha-1 recommended dose, EC30%, Aryashimi, Iran) application with a fixed dose of 1 lit ha-1 for all treatments along with oxadiazon herbicide (recommended dose of 3 L ha-1 for using in rice as pre-plant before the two leaved barnyard grass, EC12%, Shimagro company, Iran) at doses of 100, 175, and 200 ml ha-1, and oxadiargyl herbicide (recommended dose of 3-3.5 L ha-1 for using in rice as pre-emergence or at the beginning of weed emergence in transplanted rice, SC3%, Herbicide Production Company, Iran) with doses of 100, 125, and 150 ml ha-1. Weedy and weeding control (complete control by manual weeding) were considered as control treatments. Herbicides were applied by a 12 liter back sprayer equipped with a TJET 11003 nozzle, which was calibrated for spraying 200 liters per hectare, in the initial 2-leaf stage to the beginning of 4 true leaves for chemical control of weeds in the plots. The grass weeds were removed by hand. Broadleaf weeds were counted separately according to the weed species at before spraying, three and six weeks after spraying and were cut at the soil surface and dried at 70 °C in oven. Then, weed dry weight was measured with a digital scale 0.01 and the percentage reduction in density and dry weight of weeds were calculated. In addition, the amount herbicides used on rapeseed was visually assessed using the EWRS standard table. Then, yield and yield components of rapeseed including number of siliques, seed no. per silique, 1000-seed weight, seed yield, biological yield and harvest index were measured.

Results showed that the predominant weed species in the experimental plots included wild clover, queen anne᾿s lace, mallow, Anagalis spp., wild mustard, and field bindweed, which the highest frequency (31.29%) belonged to wild clover and the lowest frequency (1.03%) belonged to field bindweed. The ANOVA results showed that the reduction percentage of density and dry weight of weeds and seed yield were affected by experimental treatments; as the treatments of clopyralid + oxadiazon 100, clopyralid + oxadiazon 175, clopyralid + oxadiargyl 125 in Hyola50 hybrid and clopyralid + oxadiazon 175 in Agamax hybrid reduced the density and dry weight of weeds by 100%. While, the lowest reduction percentage of weed density and dry weight (44.74 and 55.33%, respectively) was observed in Agamax hybrid and clopyralid (1 L ha-1) treatment. Also, the highest and lowest herbicide injury on weeds were observed in clopyralid+oxadiazon 100 (9.67%) and clopyralid alone and combination of clopyralid+oxadiargyl 100 and 150 in Agamax hybrid (0%), respectively. The highest seed yield, biological yield and 1000-seed weight of rapeseed were observed in clopyralid+oxadiazon 200, oxadiargyl 125 and 150 (3377.6 kg ha-1, 11295 kg ha-1, and 3.27 g, respectively), and the lowest was observed in weedy control treatment (2064.2 Kg ha-1, 7458 Kg ha-1 and 2.87 g). 1000-seed weight is less affected by treatments and is a genetic trait. The highest and lowest number of seeds per silique under the influence of herbicide treatment were related to clopyralid+oxadiazone 175 and clopyralid+oxadiargyl 100 (23.33 and 18.17), respectively. An increase in the number of seeds per silique was observed with increasing the dose of herbicide oxadiazone in combination with clopyralid up to 175 ml ha-1. The highest number of siliques per plant was obtained in weeding treatment in Agamax hybrid with 189.33 silique per plant, which was significantly different from weedy control treatment. Also, the lowest number of weed control silique was obtained with Hayola 50 hybrid, which was not significantly different from clopyralid+oxadiazone 100 in Agamax hybrid.

According to the results, mixing herbicides is a solution to eliminate the competition of weeds with rapeseed and increase the yield so that the yield of up to 3.3 tons is obtained, which compared to clopyralide only as a control treatment. In general, the highest yield of rapeseed from plots treated with clopyralid+oxadiazon 200, oxadiargyl 125, and 150 were the best treatment in comparison with the applied treatments. The best treatment is the one in which rapeseed yield has been the highest. In addition, since clopyralid is a selective herbicide in rapeseed, it did not have sufficient efficacy due to poor control of important weeds such as wild mustard. It should also be noted that further testing of the above herbicide mixtures on rapeseed fields throughout the country is necessary in order to obtain the results that are the basis for recommending these mixtures in rapeseed.