حبیب الله چاره گانی

Tomato is attacked by root-knot nematodes (Meloidogyne spp.), reducing crop yield. The negative consequences on the environment and the high cost of producing chemical nematicides limit their application. The use of chemical fertilizers with a direct and indirect effect on the population of nematodes is considered as an environmentally friendly alternative solution. In this research, the effect of recommended minimum and maximum concentrations of Zima (soil conditioner), Nemo (growth enhancer) and Bonza (root growth stimulant) fertilizers was investigated in reducing the damage caused by M. javanica in tomato plants under greenhouse conditions. For this purpose, four-leaf stage tomato seedlings were treated with the concentrations 0.5% and 1% of Zima fertilizer, 0.1% and 0.3% of Nemo fertilizer, and 0.1% and 0.3% of Bonza fertilizer and simultaneously inoculated with 6000 nematode eggs and kept in greenhouse conditions. Sixty days after nematode inoculation, the results showed that nemo at the rate of 0.3% significantly increased the vegetative indices of healthy and infected plants. Also, the concentration of 0.5% Zima fertilizer decreased the number of eggs, galls and eggmasses in the root system, and the reproduction factor of nematode by 57.4, 34.6, 43.7, and 56.9%, respectively, compared to the control. The results of the research showed the importance of modifying the soil structure and compensating essential nutrients to reduce the damage of root-knot nematodes in tomato plants.

The pinto bean with a considerable amount of protein plays a key role in human life. Plant parasitic nematodes are known to attack pinto bean plants worldwide. Root-knot nematodes (Meloidogyne species) causes extensive damage to legume fields annually. The use of chemical fertilizers leads to instability in agricultural systems and endangers human health. The use of organic fertilizers can be a suitable alternative. The present study examined the effects of different concentrations of pigeon and poultry manures on M. javanica-infected pinto bean under greenhouse conditions. Poultry and pigeon manures were individually mixed with steam-sterilized soil at three different concentrations [1, 2, and 3% (w/w)] and the soil was poured into the 1.5 kg plastic pot. Pinto bean seeds were sown in pots and the seedlings were watered until the end of the test and fertilized as needed. Seedlings at the four-leaf stage were inoculated with 4000 eggs of M. javanica. The plants were harvested after 60 days and plant growth indices and nematode population indices were determined. The experiment was conducted in completely randomized design tests with five repetitions. The results showed that application of 2% poultry manure was the best treatment that increased shoot length, fresh and dry shoot weight, and fresh root weight in nematode-infected plants. In addition, this amount of poultry manure resulted in a reduction in the number of galls, egg mass and eggs in the root system, the number of second stage juveniles in the soil and the reproductive factor compared to the untreated inoculated control. The results of this study showed that under greenhouse conditions, the effect of poultry manure in reducing nematode damage to pinto beans was greater than that of pigeon manure.

Root-knot nematodes, Meloidogyne spp. cause 5% of the global crop losses. Silver nanoparticles (AgNPs) are a potentially effective nematicide. There are many methods to synthesize metallic nanoparticles, including using organic compounds, which are clean and environmentally friendly. In the present studies, the efficacy of as-synthesized AgNPs using Malva sylvestris extract (Ms-AgNPs) on egg hatching and mortality of the second-stage juveniles (J2) of M. javanica in vitro, and on the growth parameters of nematode infected tomato plant under greenhouse conditions was investigated. The results showed that increasing Ms-AgNPs concentration decreased the hatching rate and increased the mortality of J2. Ms-AgNPs at 107, 164 and 250 ppm reduced J2 numbers by 30, 50, and 70%, respectively, and were established as lethal doses for nematode control. Ms-AgNPs at a dosage of 250 ppm reduced the number of eggs in the root system and the nematode reproduction factor by 60.4 and 56.3%, respectively, and increased shoot length and shoot fresh weight by 11.2 and 14%, respectively. Ms-AgNPs at a very low concentration reduced the population of M. javanica without causing any harmful effects on tomato. Therefore it can be used in nematode control strategies due to its environmentally friendly composition.

The Root-knot nematodes (Meloidogyne spp.) are one of the most damaging plant pathogens with a wide host range and cause major losses to agricultural crops. The use of resistant cultivars is considered a safe, economical, and effective method to control these nematodes.

In the present study, eight melon cultivars namely Ahlam, 105, Tracey, Ronak, Deltagrin, Mac, Holar, and Veno were evaluated for their response to M. javanica. The seeds were planted in 2 kg pots and maintained under natural conditions in Khormuj city, Bushehr province. Seedlings at the four-leaf stage were inoculated with 5000 eggs and second-stage juveniles. The factorial experiment was conducted in a completely randomized design with five replicates. Sixty days after nematode inoculation, the plants were harvested and the plant growth and nematode population indices were evaluated.

The results showed that the nematode reproduction factor was significantly lower in Ronak, Deltagrin, and Veno than in the other cultivars. No significant difference was observed in shoot fresh weight of nematode inoculated and non-inoculated plants of Ronak cultivar.

Ronak, Delta-green and Veno cultivars are less susceptible to M. javanica.

Plant-parasitic nematodes cause significant yield losses in a wide range of crops. Root-knot nematodes (Meloidogyne spp.) are the most important plant-parasitic nematodes, because they widely distributed all around the world and have wide host range. Chemical nematicide is one of the primary means of control for plant-parasitic nematodes. Due to negative impact of synthetic nematicides, it will be necessary to develop other management strategies for plant-parasitic nematodes which are safe for the environment and humans. Latest interest in organic farming lead to substitution for conventional nematicides by low-risk compounds such as natural products derived from plants. Also, biological control is an interesting option to control these nematodes. Effective microorganisms (EM®) consist of a mixture of live cultures of microorganisms such as photosynthetic bacteria, which they are reported to reduce the incidence of pathogenic microorganisms.

In the present study, the aerial parts of the marigold (Tagetes erecta) were collected from Shiraz, Iran. Marigold leaves dried in shade and finely grinded using an electric grinder and a stock solution (10% w/v) was prepared. Seeds of tomato (cv. Early-Urbana) were sown in plastic pots containing 1500 g of a sterilized mixture of farm soil (sandy loam soil) and cow manure. The pots were kept under greenhouse conditions with 16:8 h light to dark photoperiod and 27 ± 4 °C. Four-leaf stage seedlings were soil-drenched (50 ml per plant) with EM® or a mixture of equal amount of EM®+ marigold leaf extract at the rate of 5, 10, 15 and 20% and simultaneously inoculated with a suspension of M. javanica (6000 eggs per pot). The experiment was carried out in a completely randomized design with five replications. Sixty days after nematode inoculation, plants were harvested and the vegetative indices including shoots length, shoot fresh and dry weight and root fresh weight and the nematode population indices including the number of eggs as described by Hussey and Barker (1973), number of galls and egg masses per root system as described by Taylor and Sasser (1978) and the number of second stage juveniles (J2s) in the pot were recorded. Finally, the reproduction factor calculated as described by Sasser and Taylor (1978). Data were subjected to one-way analysis of variance (ANOVA) for plant growth parameters and two-way ANOVA for nematode population indices using SAS 9.1 program (Statistical Analysis System Institute Inc., USA). Treatment means were compared using least significance differences (LSD) at p<0.01.

Results showed that soil drenching of EM® and EM®+ marigold leaf extract increased the plant growth parameters on inoculated and non-inoculated plants as compared to control. The treatment with EM®+ marigold leaf extract at the rate of 20% was the most effective treatment and increased shoot length, shoot fresh weight and shoot dry weight of non-inoculated plants by 33, 39 and 11% respectively, as compared to non-inoculated control plants. In the case of inoculated plants, shoot length, shoot fresh weight, shoot dry weight and root fresh weight of treated plats with EM®+ marigold leaf extract at the rate of 20% were 34, 31, 15 and 11% higher than inoculated control plants. The number of eggs and egg masses per root system and the reproduction factor were significantly reduced in treated plants with EM®+ marigold leaf extract at the rate of 15 and 20%. EM®+ marigold leaf extract at the rate of 20% reduced the number of eggs, galls, egg masses per root system and the reproduction factor by 28, 40, 37 and 27% respectively, as compared to control. The lowest numbers of egg masses were observed in the root system of tomato plants treated with EM®+ marigold leaf extract at the rate of 20%. It had significant difference than other treatments, except EM® at the rate of 20%. These data for the first time in Iran, suggest that EM® might have utility in controlling root-knot nematodes. A mixture of EM® and marigold leaf extract was more effective than alone application of EM® for control of M. javanica. Findings from this study, suggest that a mixture of equal amount of EM® and marigold leaf extract at the rate of 20% reduced M. javanica reproduction rates in tomato plants grown in greenhouse.

Root-knot nematodes, Meloidogyne species are among the most critical plant-parasitic nematodes attacking okra Abelmoschus esculentus (L.) Moench in tropical and subtropical regions. In the present study, the effects of various levels of zinc and iron on okra infected with M. javanica were investigated under greenhouse conditions in a completely randomized factorial design with five replications. Four-leaf stage seedlings of the susceptible okra, cv. Clemson Spineless were inoculated with 8000 eggs of M. javanica per pot. Five days later, the soil of each pot was treated with a combination of iron or zinc (0, 1, 3, and 6 mg∙kg-1 soil) from nano chelated iron and zinc fertilizer sources. Sixty days after inoculation, plants were harvested, and okra growth indices and nematode population indices were determined. Results showed that vegetative indices increased in most cases compared to non-treated plants. Fruit fresh weight of inoculated plants treated with iron at the rate of 1 mg∙kg-1 soil + zinc at the rate of 3 mg∙kg-1 soil from nano chelated iron and zinc fertilizer sources increased by 205%, compared to inoculated control plants. Combined application of iron at the rate of 6 mg∙kg-1 soil + zinc at the rate of 6 mg∙kg-1 soil from nano chelated iron and zinc fertilizer sources reduced the number of eggs, galls, and egg masses per root system and the reproductive factor (224, 415, 455 and 231%, respectively) compared to non-treated plants.

Root-knot nematode Meloidogyne javanica is the most economically important plant-parasitic nematode worldwide. Because of the environmental hazards of chemical nematicides used to control this nematode, there is an urgent need to replace these nematicides with alternative compounds that are environmentally friendly.

An experiment was conducted to control M. javanica infestation on tomato plants (cv. Early-Urbana) using wood vinegar at the rates of 0.3, 0.6 and 0.9 percent (v/v), Effective Microorganisms (EM®) at the rates of 5, 10 and 15 percent (v/v), humic acid at the rates of 0.2, 0.4 and 0.6 percent (v/v) and tervigo (positive control) at the rate of 0.4 percent (v/v), in greenhouse.

EM® at the highest concentration (15%) was the most effective organic compound which reduced the nematode indices. Shoot length, shoot fresh weight and shoot dry weight increased by 41, 28 and 36%, respectively. The number of eggs, galls, egg masses per root system and reproduction factor were decreased by 58, 48, 49 and 57% in treated tomato with EM® at the rate of 15%, compared to control (non-treated) plants, respectively.

The organic compounds used in the present study are effective to control M. javanica on tomato under greenhouse conditions.

Root-knot nematodes (Meloidogyne spp.) are among the most dangerous herbal parasites which destroy 8.8 to 14.6 percent of agricultural products annually. In vegetables, 50 to 80 percent damage caused by nematodes is normal. It is unavoidable to use safe methods for controlling root-knot nematodes. Plant parasitic nematodes can be inhibited using chemical fertilizers, which reduce the losses induced by plant parasites and increase total products. The aim of this study was to evaluate the effect of different levels of two macronutrients including nitrogen and phosphorous on the infection of M. javanica on eggplant (cv. Black Beauty) under greenhouse conditions.

In the current study, the levels of zero (N0), 50 (N1), 100 (N2), 200 (N3) mg nitrogen and zero (P0), 50 (P1), 100 (P2), 200 (P3) mg phosphorus per kg of soil were selected from nano-chelated nitrogen fertilizer and nano-chelated phosphorus fertilizer, respectively. The seeds of eggplant were planted in plastic pots containing 2 kg of culture media including equal amount of sand, farm soil and animal manure under greenhouse condition. The pots were irrigated daily and maintained at 27±4 °C with 16:8 h light: dark photoperiod. Four leaf stage seedlings were inoculated with five eggs and second stage juveniles of M. javanica per gram of soil, and 10 days after inoculation, different levels of fertilizers were added (100 ml per pot) to the pots through irrigation. Sixty days after inoculation, plant growth indices including shoot height, shoot fresh and dry weights and root fresh weight of the cultivated plants were recorded. Nematode population indices including number of galls and egg masses per root system, number of eggs in egg masses were also measured and finally the reproduction factor was calculated. The roots were gently washed with tap water and number of eggs in one gram of root were counted according to the procedure developed by Hussey and Barker (1973). One gram of root was stained with acid fuchsine according to the procedure developed by Byrd et al. (1983). The total number of eggs, galls and egg masses per plant root system was determined by multiplying with the root weight per plant. The final nematode population per pot was computed and finally, the reproductive factor (RF) of nematode was calculated by dividing the final nematode population by the initial nematode population (10000 eggs and second stage juveniles of M. javanica). Data on plant growth and nematode indices of the experiments were subjected to a factorial analysis of variance (Two-way ANOVA). Means were compared with least significant differences (LSDs) to identify significant difference at probability levels of P≤0.05 using SAS 9.1 software (Statistical Analysis System Institute Inc., USA) in a CRD (completely randomized design) with four replicates.

In nematode inoculated plants, the difference between shoot height and shoot fresh and dry weight of treated plants by phosphorus at the rate of 100 mg/kg soil and non-treated by nitrogen (N0P3) with control plants (N0P0) was significant. Similar results were observed in nematode inoculated plants treated by nitrogen and phosphorus at the rate of 50 and 100 mg/kg soil, respectively (N1P3), with nematode inoculated plants treated by nitrogen at the rate of 50 mg/kg soil and non-treated by phosphorus (N1P0), nematode inoculated plants treated by nitrogen and phosphorus at the rate of 100 and 100 mg/kg soil, respectively (N2P3), with nematode inoculated plants treated by nitrogen at the rate of 100 mg/kg soil and non-treated by phosphorus (N2P0) and also nematode inoculated plants treated by nitrogen and phosphorus at the rate of 200 and 100 mg/kg soil, respectively (N3P3), with nematode inoculated plants treated by nitrogen at the rate of 200 mg/kg soil and non-treated by phosphorus (N3P0) (P≤0.05). The results showed that using 100 mg nitrogen and 100 mg phosphorus per kg of soil from nano-chelated nitrogen fertilizer and nano-chelated phosphorus fertilizer, as the best treatment used in this experiment, decreased number of eggs, galls and egg masses per root system and reproduction factor of nematode by 53, 52, 62 and 55%, respectively. Therefore, nano-chelated nitrogen and phosphorus fertilizers, as two chelated fertilizers produced using nanotechnology, can decrease the population of M. javanica in eggplant cultivated in the greenhouse. Soil drenching of these water-soluble nano-fertilizers 10 days after infection of the eggplants by M. javanica can also reduce the population of nematode.

Background and Objectives Bacterial leaf blight of rice, caused by Xanthomonas oryzae pv. Oryzae, is a destructive bacterial disease of rice in growing regions of this plant worldwide. Although the application of chemicals significantly reduces plant diseases, planting resistant cultivars remains the most effective strategy to control crop diseases. This study aims to evaluate the resistance of four rice cultivars Hashemi, Lenjan, Firuzan and Gilane to bacterial blight, under growth chamber conditions. Materials and Methods The population growth and symptom development were monitored after introduction of bacterial suspensions (107 cfu ml–1) into leaf intercellular spaces. In this investigation, the effects of Xanthomonas oryzae pv. oryzae stress on the activity of superoxide dismutase, catalase and peroxidase in different rice leaves were evaluated. Antioxidant assays were performed with leaf samples collected on 4th day after infection (4th DAI), 8th DAI and 12th DAI. Results After infiltration of different cultivars with the bacterium, the highest populations were detected in Hashemi cultivar, followed by Gilane and Firuzan cultivars 14 and 16 days after infiltration. At 12th DAI, the higher peroxidase activity was observed in Lenjan cultivar. At 12th DAI, the activity of superoxide dismutase was increased 33.3, 23.5, 15.5 and 33.3 percent, respectively, in Lenjan, Gilane, Hashemi and Firuzan cultivars compared to the control. Discussion The present study showed that based on the population dynamics of Xanthomonas oryzae pv. oryzae in different rice leaves, pathogenicity (percentage of necrotic area per leaf) and antioxidant activity, Hashemi was the most susceptible cultivar and Lenjan was the most resistant cultivar to bacterial blight.

Root-knot nematodes(Meloidogyne spp.) are the most important parasitic nematodes infecting cucurbits plants. These nematodes cause 5% loss in crop production and also provide favorable conditions for co-infection with other plant pathogens. Trichoderma harzianum Rifai is a potential bio-control agents for controlling the plant pathogens, including plant parasitic nematodes. In order to find the effective isolate/s of T. harzianum for management of root-knot nematodes on cucumber, a suspension of 107 spores/ml of four isolates of T. harzianum with 36, 39, 42 and 43 codes was evaluated by soil drenching method. Twenty four hours after soil drenching of fungus isolates, four leaf stage seedlings of cucumber (cv. Super Dominus) were inoculated with 2000 eggs and second stage juveniles of Meloidogyne javanica and kept for two months in the greenhouse and the experiment was conducted as a completely randomized design with four replicates. The results showed that the isolate Th42 was the most effective isolate on reducing the biological activity of nematode as compared to other treatments. The isolate Th42 reduced the number of eggs, galls, egg masses and reproductive factor by 69.2, 81.8, 88.6 and 70%, respectively, as compared to control treatment.

Wheat bacterial blight disease caused by the bacterium Pseudomonas syringe pv. syringae (Pss) is one of the important diseases of wheat in the world. The expanding the diseases resistance to chemical compounds has led to the researches into the new antimicrobial agents finding.  Studies have shown that plant essential oils induce biological activity against plant pathogenic bacteria and can be used as an environment friendly and safe way to control the disease. These compounds have the least harm to the ecosystem and can be used as an alternative to toxic compounds for controlling plant diseases. This study was designed to evaluate the antimicrobial activity of the essential oils obtained from the aerial parts of Rosmarinus officinalis, Mentha spicata and Thymus daenensis, against Pss on wheat cultivars Pishtaz, Sirvan and Chamran under greenhouse conditions. In this study, all essential oil treatments significantly reduced the severity of wheat bacterial blight, especially on Pishtaz cultivar, and the percentage of necrotic area on the leaf 30 days after bacterial inoculation. The highest reduction in the severity of the disease was obtained by Mentha spicata and Thymus daenensi essential oils. The findings of the present study suggest that essential oils of Rosmarinus officinalis, Mentha spicata and Thymus daenensis are capable to be used as antimicrobial agents.

Gorgan in Golestan province is substantially considered as an important region for production of agricultural crops in Iran. Plant-parasitic nematodes may cause direct or indirect damages to the plants in this region. Although some members of Merliniidae, Telotylenchidae or Pratylenchidae (Nematoda: Tylenchoidea( have been reported from different crops of Gorgan so far, there is no adequate and accurate information on these nematodes in association with many agricultural crops in Gorgan for making decisions on their management. The aim of the present study is to identify plant-parasitic nematodes of these three families in the agricultural field crops of Gorgan region and to determine their frequencies in the studied area. In order to identify the plant parasitic nematodes from the families of Merliniidae, Telotylenchidae and Pratylenchidae associated with the important field crops of Gorgan, Iran, 64 soil samples were collected from different parts of the region during 2014-2015. The nematodes were extracted, fixed and transferred to anhydrous glycerin. The permanent slides were prepared from the extracted nematodes and necessary measurements were made. Finally, the nematodes were identified based on morphological and morphometric characters, using available identification keys. In this study, 11 species belonging to seven genera were identified as Amplimerlinius macrurus, Merlinius brevidens, M. microdorus, Paramerlinius hexagrammus and Pratylenchoides ritteri from family Merliniidae, Tylenchorhynchus brassicae and T. crassicaudatus from family Telotylenchidae, and Pratylenchus neglectus, P. sefaensis, P. thornei and Zygotylenchus guevarai from family Pratylenchidae. Tylenchorhynchus crassicaudatus was found in the rhizosphere of soybean plants in Gorgan. Description, morphometrics, line drawings and photomicrographs were provided for this new record of nematodes. Among the identified species, P. sefaensis, M. brevidens and M. microdorus were the most distributed species, with 26.6, 25.0 and 23.4 % relative frequencies, respectively. Tylenchorhynchus crassicaudatus is reported for the first time in Iran and cited here. Furthermore, differences of morphological and morphometric characters of this species with other closely related species namely T. thermophiles, T. paratriversus, T. kashmirensis and T. mashhoodi are discussed. The morphological and morphometric characters of the present population are congruent to those of the type population type, except for hyaline region of tail being slightly shorter (4-7 vs 7-13 µm). Our population differs from the closely related species in some features related to female tail (shape, length and the number of annuli on the ventral side), in the absence of post-rectal sac, spicules and gubernaculum lengths, distance of DGO from stylet knobs and position of vulva.

In order to identify the plant-parasitic nematodes associated with medicinal plants in Boyer-Ahmad region, Iran, 84 soil and root samples were collected during 2015-2016. The nematodes were extracted from soil samples, according to the sieving-centrifugal flotation method, and then fixed and transferred to glycerin according to the modified De Grisse’s method. Identification of the nematodes insides the roots was also done with the Hooper’s staining technique. After microscopic observations of the permanent slides, the necessary measurements were made. Finally, the extracted nematodes were identified at species level using available diagnostic keys. In this study, 28 species belong to 14 genera were identified as follow:Amplimerlinius globigerus, Aphelenchoides cyrtus, A. haguei, A. varicaudatus, Helicotylenchus digitiformis, H. digonicus, H. exallus, H. pseudorobustus, H. varicaudatus, H. vulgaris, Longidorus africanus, Meloidogyne hapla, M. javanica, Merlinius brevidens, Mesocriconema antipolitanum, M. lobellum, Nagelus obscurus, Pratylenchoides ritteri, Pratylenchus cruciferus, P. curvicauda, P. delattrei, P. neglectus, P. sefaensis, P. sudanensis, P. thornei, Rotylenchus cypriensis, Scutylenchus rugosus, Xiphinema pachtaicum, Zygotylenchus guevarai.
Mesocriconema lobellum and Pratylenchus sudanensis were recovered from the rhizosphere of marsh-mallow and horehound plants, respectively and are reported for the first time from Iran here.

Pseudomonas syringae pv. syringae (Pss), the causal agent of bacterial canker of stone fruits, is a dangerous pathogen that attacks more than 200 different plant species. Due to the importance of disease, the purpose of this study was to identify the causal agent of the disease in Kohgiluyeh and Boyerahmad province and comparing the resistance of some cherry cultivars to this pathogen. During 2015-2016, 33 bacterial strains were isolated from stone fruit plants with canker, gummosis, and leaf spot symptoms from different regions of Kohgiluyeh and Boyer-Ahmad province. Isolates were rod-shaped, motile, gram-negative, obligate aerobe, oxidase negative, catalase, levan and tobacco hypersensitive reaction positive, arginine dihydrolase and potato rot negative. The genes responsible for syringomycin synthesis (syrB) and syringomycin secretion (syrD) were detected in all isolates. All strains were able to produce necrosis spots on cherry fruit but showed different virulence. Regarding the phenotypic characteristics, pathogenicity test and PCR results of this study, all isolates were identified as Pss. To study the resistance of cherry plants, Takdaneh Mashhad, Ghaheri and Surati cultivars were selected. There was a significant difference between different cultivars, based on the number of the necrotic lesion on the leaf, length of the necrotic region on the branch and bacterial population in leaf tissue. Among the different cherry cultivars studied in this research, Takdaneh Mashhad cultivar was the most susceptible and Surati cultivar showed the least sensitivity to Pss.

One of the most devastating plant parasitic nematodes of the world is the root lesion nematode Zygotylenchus guevarai. This nematode was recorded from most of the countries in association with the roots of various hosts. In a lovage (Levisticum officinale ) farm with vascular wilt symptoms at Boyer-Ahmad county, the fungus Fusarium oxysporum was isolated from the infected roots and plant-parasitic nematode Zygotylenchus guevarai was also recovered from the roots and rhizospheric soil. After that, infected lovage plants with Z. guevarai were treated by 0.0, 0.05 and 0.1 g cadusafos (Rugby)/Kg of soil. The experiments were carried out in a completely randomized design with four replications under greenhouse conditions and distilled water treatment was used as control. Results showed that Rugby with concentration of 0.05 g/Kg of soil showed 81, 47.9 and 48 while concentration of 0.1 g/Kg of soil showed 91.4, 73.7 and 73.5 percent reduction of nematode population in soil, final population and reproduction factor, respectively. Also, Rugby with concentration of 0.05 and 0.1 g/Kg of soil showed 281 and 149 percent increase in nematode population in root, respectively.

Bacterial blight disease of rice, caused by Xanthomonas oryzae pv. oryzae, is one of the most important diseases of rice worldwide. Incidence of this disease has been reported in Iran. In present study, antibacterial effects of some medicinal plants of Kohgiluyeh and Boyer-Ahmad province on this bacterium as well as on Pseudomonas fluorescens CHA0 was investigated. Antimicrobial effect of essential oils of Thymus daenensis, Rosmarinus officinalis, Foeniculum vulgar, Mentha spicata, Mentha piperita and Pelargonum graveolens was determined by agar diffusion method, under laboratory condition. Minimal inhibitory concentration (MIC) and Minimal bactericide concentration (MBC) of essential oils were also determined. The results showed that, at the concentrations of 4 and 100 mg/ml, the essential oil of T. daenensis had the highest antibacterial effect and at the concentration of 4 mg/ml, Mentha spicata had the lowest antibacterial effect. At the concentration of 1 mg/ml, essential oils of Mentha piperita, Mentha spicata and Foeniculum vulgar showed the most antibacterial activity. It was found that Xanthomonas oryzae pv. oryzae was the most sensitive to Thymus daenensis with MIC of 0.122 mg/ml and MBC of 0.245 mg/ml, while Pseudomonas fluorescens CHA0 was the most sensitive to Foeniculum vulgar with MIC of 1.95 mg/ml and MBC of 3.90 mg/ml.

The effect of different concentrations of mallow (Malva sylvestris) and poppies (Papaver rhoeas) leaves and walnut (Juglanse regia) green husks extracts were investigated on hatching and mortality of second-stage juveniles of Meloidogyne javanica under experimental conditions. In J2 mortality test, the extracts were used in 14 levels of mallow (0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.75, 1, 1.25, 1.5 and 2%), 7 levels of poppy (0.5, 1.5, 2, 2.5, 3, 3.5 and 4%) and 8 levels of walnut green husks (1, 2, 3, 3.5, 4, 4.5, 5 and 6%). In three independent tests, controlling effect of 100 milliliters of the obtained lethal concentrations (LC20, LC50 and LC80) of each extracts (0.36, 0.58 and 0.94% for mallow; 2.3, 2.9 and 3.8% forpoppies; 2.68, 4.07 and 5.18% for walnut green husks) on M. javanica were evaluated under the greenhouse condition. According to the results of this study, the nematicidal effect of all tested extracts against M. javanica was proved under laboratory conditions. In greenhouse trials, any increase in the concentration of plant extracts significantly improved the growth indices of tomato plants and also the obtained LC80of mallow, poppy and walnut green husks extracts significantly reduced the number of galls by 59, 71 and 74%, respectively, and the reproduction factor by 56.7, 85 and 87%, respectively, when compared to the control.

Root lesion nematodes are one of the most important and fatal plant parasites. They often move between soil and host plants roots, during all stages of their life. Root lesion nematodes migrate and feed within the roots, therefore they cause necrotic lesions on the surface and throughout the cortex of infected roots. Their attack to the root can result stunting of plant root system as well as reduction in plants growth and eventually host kill. Different management methods such as the planting of resistant genotypes, crop rotation, fallow periods and use of biological control agents are successfully practiced against these nematodes. In this paper a brief discussion of economic damages, importance, taxonomy, biology and symptoms of Pratylenchus thornei attack and the most efficient management methods are presented.

Root-knot nematodes are one of the most important plant parasitic nematodes. The damage of these nematodes on tomatoes is estimated about 20-30%. One of the latest methods for controlling pests and plant diseases is application of organic products and use of natural ingredients with microbial and herbal origin. In order to reduce the damage of root-knot nematode in tomato plants, the nematicidal effects of aqueous extract of oak (Quercus branti L.) were evaluated on root-knot nematode, Meloidogyne javanica in vitro as well as in greenhouse conditions. An experiment was conducted in a completely randomized design. The treatments consisted of 1- plant parts (leaf and fruit) 2- plant extracts (at five concentrations, 1%, 2%, 3%, 5% and 7% for laboratory tests, and 0.05%, 0.1%, 0.15%, 0.25% and 0.35% (g dry powder in 100 grams of soil) for greenhouse experiments). Extracts of different parts of both tested plants caused maximum mortality of the second stage larvae, at the rates of 5% and 7%. Leaf and fruit extract at the rate of 7% caused 100% larval mortality. In case of reproduction factor, none of treatments had hazardous effect on plant growth including root and shoot length, fresh and dry weight. Between all treatments, the best treatment was identified at the rate of 0.35%, which was effective enough against nematode and also had no harmful effect on the tested plant.

Root-knot nematodes (Meloidogyne spp.) are the most important plant pathogenic nematodes that reduce yield of economic plants worldwide. Infection by the root-knot nematodes cause gall formation on roots, prevent the normal growth and finally severe reduction in tomato production. In this experiment, effect of two plant species including Prangos ferulacea and Satureja hortensis against M. javanica, were investigated under greenhouse and laboratory conditions. The experiment was laid out in a randomized complete design with four replicates. Under laboratory conditions, combination treatment were used with 1: leaves of Prangos ferulacea and Satureja hortensis and 2: seven concentrations of leaves extract including 0.5, 1, 2, 3, 5, 7 and 9% w/v. Results showed that at 9% w/v, the highest percentage of mortality of second stage larvae (100%) was caused by both extract under. Under greenhouse conditions, five doses of leaf powder including 0.1%, 0.15%, 0.25%, 0.35% and 0.45% were applied. In greenhouse experiment, 0.45% of leaves powder of both plants showed more efficiency than the other doses.

In order to identify the plant parasitic nematodes of the families Dolichodoridae and Pratylenchidae (Nematoda: Tylenchomorpha) collected from green space and gardens in Shiraz, Iran, 67 soil and root samples were collected from different localities of the region during 2014-2015. The nematodes were extracted, fixed and transferred to glycerin according to the De Grisse method. The permanent slides were prepared from the extracted nematodes and studied by light microscope. In this study 15 species namely Amplimerlinius globigerus, Merlinius brevidens, Trophurus pakendorfi, Tylenchorhynchus clarus, T. dubius, T. iphilus, T. mashhoodi, T. teeni, Pratylenchus ekrami, P. thornei, P. unzenensis, Zygotylenchus guevarai, Helicotylenchus digonicus, H. pseudorobustus and Rotylenchus buxophilus were identified. The species T. pakendorfi, T. iphilus and P. ekrami as new records of Iranian nematode fauna, along with P. unzenensis are redescribed.

During a compatible interaction, root-knot nematodes (Meloidogyne spp.) induce the root cells dedifferentiation into multinucleate feeding cells, known as giant cells. Hyperplasia and hypertrophy of the cells surrounding the head of nematode lead to the formation of a root gall. Different studies showed that the transformation of root cells into hypertrophied feeding structures, with unique morphology and functions, require some changes in the expression of a large number of genes. Previous approaches, based on differential gene expression between healthy and infected plants, analyses of known candidate genes by promoter GUS fusion or in situ hybridization and promoter trap strategies, have resulted in the characterization of about 50 genes of plant that are up regulated and 10 genes that are down regulated in giant cells. Microarray technology makes it possible to generate large-scale information about patterns of gene expression during plant–nematode interactions. A DNA microarray is a collection of microscopic DNA spots attached to a solid surface. Each DNA spot contains 10−12 moles of a specific DNA sequence, which are known as probes. These can be a short section of a gene or other DNA element that are used to hybridize a cDNA or cRNA sample that called as target. Probe-target hybridization is usually detected by detection of fluorophore or silver labeled targets.

Effect of different levels of nitrogen, phosphorus, iron and zinc on the activity of root-knot nematode (Meloidogyne javanica) on cucumber, cultivar Super Amelia, and the vegetative growth indices of the host plant, was investigated under greenhouse conditions. Combination of levels 0, 50, 100, 200 and 400 mg/kg of soil of nitrogen and 0, 25, 50 and 100 mg/kg of soil of phosphorous, from urea and triple superphosphate sources, respectively, also combination of 0, 2.5 and 5 mg/kg of soil of zinc and iron, from zinc sulfate and Fe-chelat sources, respectively were tested in 1.5 kg pots filled with field soil, in two independent experiments The experiments were done in randomized complete block designs, each with five replicates. Each pot was inoculated with five eggs or juvenile two/gram of soil, at six-leaf stage of plant. The results showed that application of 100 mg of nitrogen and 100 mg of phosphorus per kg of soil, also five mg of zinc and 2.5 mg iron per kg of soil caused a significant increase in the plant shoot length, shoot fresh and dry weight. The number of eggs, egg masses and galls were also decreased.