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Heterodera schachtii is the most important nematode of sugar beet worldwide. Application of organic matter can reduce populations of plant-parasitic nematodes. In this study, the inhibitory effects of creeping thistle, tall sisymbrium, liquorice, narrow-leaf plantain, wild lettuce, castor bean, French marigold, cornflower, wild safflower and arugula on sugar beet cv. Sharif and H. schachtii were investigated in two microplot experiments. The first experiment was conducted in pasteurized mixed field soil and river sand, and the second in field soil, both with an initial population of 4200 eggs/plant. Also, the effects of the treatments on nematode egg hatching and root penetration were studied in a glasshouse experiment. The results showed that adding plant powders to pasteurized soil had no significant effect on the infected sugar beet growth indices. However, except marigold, the other treatments caused a relative increase in taproot weight of 5% to 241% compared to the control. Cornflower, wild lettuce and wild safflower increased taproot weight more than twofold compared to the control. Moreover, creeping thistle, castor bean and plantain caused a relative decrease in nematode final population and reproduction factor. In field soil, castor bean, marigold, wild lettuce, cornflower and sisymbrium increased taproot weight by at least twofold, and arugula increased sugar content by 1.2-fold. The treatments had no significant effect on the nematode indices. Plantain and wild lettuce caused a relative decrease in the nematode reproduction factor. In glasshouse experiment, wild lettuce caused the greatest reduction in egg hatching and safflower reduced nematode penetration into the roots.

Reducing the damage of the cyst nematode Heterodera schachtii is one of the research fields in sugar beet producing countries. Using chemical fertilizers can improve soil fertility and reduce damages of plant parasitic nematodes. In this study, the effects of ammonium sulfate, calcium sulfate, zinc sulfate, potassium sulfate, potassium nitrate, sodium silicate, triple superphosphate, iron sequesterine and sulfur on H. schachtii and growth parameters of susceptible sugar beet cultivar (cv Sharif) were investigated in two experiments. The first experiment was performed in plastic pots containing 6 kg of pasteurized field soil and river sand (1:1), and the second one in pots filled with 9 kg of field soil for four and five months, respectively, both under microplot conditions. Fertilizers were mixed with pots soils before sowing and the nematode was inoculated by adding 200 g of infested soil containing 18 cysts with 4200 eggs. The results showed that chemical fertilizers and sulfur did not have significant effects on growth of the infected sugar beet plants in pasteurized mixed or field soils, and some of them reduced it. In the pasteurized soil, zinc sulfate 50 kg/ha, iron sequestrene 5 kg/ha, sodium silicate 10 kg/ha and triple superphosphate 100 kg/ha caused a relative decrease of more than 67% in the nematode final population and reproduction factor. In the field soil, these indices in triple superphosphate 100 kg/ha and sulfur 100 and 200 kg/ha were lower than other treatments, but were at the same statistical level with the control. The third experiment was performed in small containers filled with infested soil to investigate the effects of treatments on nematode egg hatching in greenhouse. The results showed that the highest hatching was happened in the treatment of ammonium sulfate 200 kg/ha, which was statistically at the same level with triple superphosphate 100 kg/ha.

Phytochemicals of some plants are suppressive to the root-knot nematodes (Meloidogyne spp.). In this study, effects of aqueous extract or dry powder of several plants on the activity of M. incognita and M. javanica were investigated. Treatment of second stage juveniles (J2s) of the nematodes with aquatic extracts of 25 plant species under laboratory conditions showed that after 48 hours, extracts of eruca, ornamental chili pepper, tarragon, caster bean, sesame, thistle, chinaberry and dyer's crotoncaused more than 50% mortality of the J2s of both nematodes. In pasteurized‏ soil, extracts of scarlet sage and safflower seed with 78.9% and 46.9% reduction of reproduction factors (RFs) of M. incognita and M. javanica, respectively, were the most effective plants in treatment of tomato plants (cv. Early Urbana) with 13 different plant extracts. In addition, eruca and creeping thistle extracts reduced RFs of both species. None of the treatments affected fresh and dry shoot weight of tomato. In field soil, extracts of eruca and caster bean with 57.2% and 51.0% reduction of RFs of M. incognita and M. javanica in tomato plants, respectively, were the most effective extracts among eruca, caster bean, tarragonand creeping thistle plants. All treatments significantly increased the fresh shoot weight of infected tomato. In pasteurized‏ soil, scarlet sage powder with 70.3% and creeping thistle with 49.7% had the highest effect on RF reduction of M. incognita as compared to ornamental chili pepper, castor bean, chinaberry and safflower seed.

In recent years, non-chemical control of common species of the root-knot nematodes (Meloidogyne spp.), including soil enrichments by organic matters, animal manures and chemical fertilizers has received considerable attention. In 2014, in an experiment, effects of two levels (10 and 25 mg/kg) of sulfur fertilizers viz. ammonium sulfate, calcium sulfate, potassium sulfate, magnesium sulfate and zinc sulfate, and the levels of 25 and 50 mg/kg of elemental sulfur on the activity of the root-knot nematode M. incognita, in pasteurized soil were studied in greenhouse. Seedlings of cucumber cv. Negin at three or four-leaf stages were inoculated with two eggs or second stage juveniles of the nematode/g of soil. The results of two trials showed that magnesium sulfate 10 mg/kg caused 179% increase in the yield on average. The highest reduction was recorded in the number of eggs/g of root and reproductive factor in 25 mg/kg level of calcium sulfate with 71.6% and 58.6%, decrease followed by 25 mg/kg sulfur with 69.1% and 57.0% decrease respectively. The treatment of 50 mg/kg of sulfur was also in the next rank.

Legumes may be considered as the second most important source of high-quality protein after cereals. According to available reports, more than 35 species of nematodes belonging to 20 different genera of plant parasitic or fungal nematodes including Aphelenchoides, Basiria, Boleodorus, Criconemoides, Helicotylenchus, Hemicriconemoides, Heterodera, Hoplolaimus, Malenchus, Meloidogyne, Merlinius, Paratylenchus, Pratylenchoides, Pratylenchus, Rotylenchulus, Trophorus, Tylenchorhynchus, Tylenchus, Xiphinema and Zygotylenchus are reported from the legume fields worldwide. Kermanshah province with a cultivated area of 135060 hectares is the second legume producer in Iran. Plant parasitic nematodes associated with legumes have been identified in some provinces of Iran including Markazi (Khomein county), Lorestan and North Khorasan. Despite the fact that the province has been cultivated in such large area and the amount of legume production has been high in the country, so far no comprehensive study has been done on the identification of plant parasitic nematodes in Kermanshah province. In a few surveys, only three species of plant parasitic nematodes namely Pratylenchus thornei, Pratylenchoides ritteri and Paratylenchus elachistus have been recovered from chickpea fields in this province. Therefore, the aim of this research was to identify and determine the dominant species of important plant parasitic nematodes in the legume fields and determine their distribution in Kermanshah province. In order to identify and determine distribution of the most common plant parasitic nematodes, 173 root and soil samples were collected from legume fields (chickpea, lentil and faba bean) in several localities of Kermanshah province, during years 2016-2017. After extraction, fixation and transferring to anhydrous glycerol, the nematodes were mounted on microscopic slides and studied by using a light microscope, equipped with digital camera. Finally, they were identified using available identification keys. Based on morphometric and morphological characteristics, in this study, 19 species of the infraorder Tylenchomorpha viz. Aphelenchoides graminis, A. obtusus, Aphelenchus avenae, Ditylenchus adasi, D. equalis, D. medicaginis, D. myceliophagus, D. parvus, Filenchus vulgaris, Helicotylenchus scoticus, Merlinius brevidens, Nagelus obscurus, Neopsilenchus magnidens, Pratylenchus thornei, Pratylenchoides ritteri, Scutylenchus rugosus, S. tartuensis, Trophorus ussuriensis and Tylenchorhynchus parvus were identified. The species F. vulgaris, D. medicaginis, P. ritteri, H. scoticus, M. brevidens and T. parvus were the most common species in the legume fields of Kermanshah province with 33.8, 29.4, 27.9, 26.5, 13.2 and 13.2 percent frequency rates, respectively. Among 12 cities under legumes cultivation in the province, Kermanshah with 16 species, Ravansar and Gilan gharb each with nine species, Eslam Abad and Kerend Gharb each with seven species, had highest number of the nematode species. In chickpea fields, F. vulgaris, P. ritteri, H. scoticus and D. medicaginis were the most prevalent species, in lentil fields D. medicaginis, H. scoticus, T. parvus, F. vulgaris and S. tartuensis had higher frequency rates, and in faba bean fields D. medicaginis, M. brevidens and A. avenae were highly distributed species. The species Aphelenchoides obtusus, which has not been previously described in Iran, is described in full, and the males of A. obtusus is reported for the first time from Iran. Also A. graminis, D. medicaginis and P. ritteri which are more common or have morphological or morphometric diversity were described briefly. Seven species namely Aphelenchoides graminis, A. obtusus, Ditylenchus equalis, Nagelus obscurus, Scutylenchus tartuensis, Trophurus usuriensis and Tylenchorhynchus parvus are reported for the first time from legume fields in Iran. These seven species with together six other species namely D. adasi, D. parvus, Helicotylenchus scoticus, Merlinius brevidens, S. rugosus and Neopsilenchus magnidens are reported for the first time from Kermanshah province. In the present paper, description of four species with together their morphometric data and illustrations (line drawings or photomicrographs) are provided. Also discussions were made on the diagnosis and relationships of these four species either with other populations or closely related species. Among the 19 identified species, it seems that Pratylenchoides ritteri (with potential damaging effects on legumes), and Ditylenchus medicaginis and Helicotylenchus scoticus (with high frequency and distribution in the studied regions) should be considered as important species for conducting further supplemental surveys in Kermanshah province. A very damaging species of nematodes to legumes, Pratylenchus thornei, was found only in 4.4 % of the studied fields, and the other important group of nematodes, root-knot nematodes (Meloidogyne spp.) were not recovered from the legume fields of Kermanshah province.

Ornamental plants are grown for decorative purposes in gardens and landscape design projects, as houseplants, for cut flowers and specimen display. The cultivation of these, called floriculture, forms a major branch of horticulture. Nematodes are a diverse group of wormlike animals found in a number of habitats. Plant-parasitic nematodes are recognized as one of the greatest threats to crops throughout the world. Nematodes alone or in combination with other soil microorganisms have been found to attack almost every part of the plant including roots, stems, leaves, fruits and seeds. Hoplolaimidae is a family of plant parasitic nematodes. The common name, spiral nematode, is most often applied to nematodes in the genus Helicotylenchus, but it is also sometimes applied to other genera in the family Hoplolaimidae. These are called spiral nematodes because their bodies tend to curl into a spiral when the nematodes are relaxed or dead. The spiral nematodes have been reported in the worlds associated with various cultivated horticultural, agronomic, ornamental, and turfgrass plants.
Materials and Methodes: In order to identify the ornamental plants parasitic nematodes in Guilan province, 115 soil samples from rhizosphere of various species of ornamental plants in greenhouse and landscaping were collected from different parts, during the summer and fall in 2011-12. After extraction, fixation and transferring nematodes to anhydrous glycerol, the nematodes were mounted on permanent microscopic slides and nematode species were identified by using light microscope, equipped with drawing tube and digital camera, based on morphological and morphometric characters using valid identification keys.
In this research, 7 nematode species belonging to Hoplolaimidae family including Helicotylenchus dihystera, H. erythrinae¡ H. exallus, H. Microlobus, H. Pseudorobustus, H. sharafati and Scutellonema brachyurus were indentified. Two species, H. pseudorobustus and H. sharafati were reported for the first time from Iran.
H. microlobus is distinguished from close speciecs by lack of areolation on the tail, fusing of inner incisures of the lateral fields distally for about two annules and unclear phasmid. Distinguishable charatcters of H. Sharafati from close species are as below: less labial annules, angular spear knobs and differently shaped tail with characteristic endings of lateral fields. There is no measurement and description of H. erythrinae available in Iran so the description of this species is also illustrated.

For identification of nematode species of the genera Ditylenchus and Nothotylenchus, 341 plant and soil samples from farms, orchards and pastures of Fars, Kohgiluye and Boyer-Ahmad, Bushehr and Hormozgan provinces, and 32 samples from Mazandaran, Golestan, Hamadan, Lorestan and Ilam provinces were collected, during 2013-2016. After extraction, killing and fixing, the extracted nematodes were transfered to anhydrous glycerol. Species identification was done using light microscope equipped with digital camera, based on morphometric and morphological characters. The results showed that the genera were existed in 54.7% of the samples. In this study, 12 species of Ditylenchus and five species of Nothotylenchus were identified. D. myceliophagus and D. medicaginis with 38.8% and 38.1% frequency, respectively, and N. geraerti with 60% frequency were the most common species. The species N. basiri, D. geraert and D. solani are new records and were described for the first time from Iran. Moreover, descriptions of N. adasi and N. medians, and the identification key for the Iranian species of the genera Ditylenchus and Nothotylenchus were provided.

Effects of chemical fertilizers on Meloidogyne incognita activity and Pseudomonas fluorescens CHA0 were studied in vitro. The results showed that the chemical fertilizers increased 67.0-94.8% mortality of the second stage juveniles and decreased 43.8-80.8% egg hatching of the nematode, but did not inhibit the bacterium growth on NA and LB culture fertilizer. Effect of combined application of P. fluorescens CHA0 and chemical fertilizers, on the activity of M. incognita and growth indices of infected tomato plant cv. Early Urbana was studied in greenhouse in three turns. Results showed that application of triple superphosphate, sulphur, zinc sulphate and copper sulphate in combination with P. fluorescnse CHA0 significantly increased the growth parameters of tomato plants. In the first trial, combination of the bacterium with 50 mg/kg of nitrogen (urea) caused 54.9% and 67.3% reductions in galls and egg masses/gram of root, respectively, and with 10 mg/kg of phosphorus caused 18% reduction in reproduction factor (RF) of the nematode. In the second trial, the bacterium and 5 mg/kg of cupper caused 83.2% and 80.6% reductions in galls and egg masses/gram of root, respectively, and with 100 mg/kg of nitrogen caused 81.7% reduction in RF. In the third trial, the bacterium and 5 mg/kg of cupper caused 74.7% and 81.2% reductions in galls and egg masses/gram of root, respectively, and with 100 mg/kg of nitrogen caused 67.6% reduction in RF. Combination of P. fluorescens CHA0 and copper sulphate was the best treatment in increasing tomato growth parameters and decreasing the nematode indices.

Effect of 10% aqueous extracts of inhibitory plants viz. Plantago major, Ricinus communis, Eruca sativa and Tagetes sp. on Meloidogyne incognita activity and Pseudomonas fluorescens CHA0 was studied. The results showed that the extracts increased 31-42% mortality of the second stage juveniles and decreased 37.5-60.0% egg hatching of the nematode, but did not inhibit the bacterium growth. The combined effects of green manures of plants (12 g/kg of soil) and bacterium (cfu108) on activity of the nematode and growth parameters of tomato (Early Urbana) were studied in 3.5 kg pots, containing sterilized mixed or non-sterilized farm soils. The results showed that in presence of the nematode and in sterilized soil, marigold-bacterium with 66.2 and 60.9% increases, and in non-sterilized soil castor with 29.1 and 18.3% increases in shoot fresh and dry weights, respectively, had the highest impacts. Plantain-bacterium decreased 95.9 & 86.0% of eggs/g of root and 92.9 & 95.2% of nematode reproduction factor in sterilized or non-sterilized soils, respectively. In addition, plantain decreased 93.9 & 84.5% of eggs/g of root and 90.7 & 95.9% of nematode reproduction factor, respectively. The results of the greenhouse test on usage of eruca green manure and bacterium in 12 kg pots, containing sterilized mixed soil, showed that in the presence of nematode, eruca with 15.0, 2.2 and 48.3% increases in shoot fresh, shoot dry and fruit weights, respectively had the greatest impact. Moreover, eruca-bacterium decreased 55.2 and 52.4% of egg or gall/g root, respectively and 65.5% of reproduction factor.

Effects of aqueous extracts of plantain, castor, marigold and eruca on egg hatching and the mortality of second stage Juveniles (J2) of Meloidogyne incognita, was studied in vitro. Also the effects of their green manures (12 g/kg soil) and Paecilomyces lilacinus alone and in combination on the root-knot nematode and growth parameters of infected tomato (CV Early Urbana) in sterilized mixed soil and non-sterilized farm soil were studied, under greenhouse conditions. The results of in vitro test showed that all plants extracts increased the mortality of J2, and plantain and eruca reduced the egg hatching, significantly, and they had not negative effect on P. lilacinus. The result of greenhouse test in sterilized soil revealed that in the presence of the nematode, marigold- fungus spore suspension caused 140.5% increase in the shoot height of tomato plants. In addition, marigold treatments caused 11.4-11.8 and 20.1-23.1 folds and caster 10.0-10.1 and 10.0-17.7 folds in fresh and dried shoot weight, respectively. In non-sterilized soil, caster treatments with 47.9-67.5% and 32.4-140.5% increases in fresh and dried shoot weights have the highest effects. The nematode gall index in both tests was 4.2-5.0. Except for the treatment of plantain-fungus spore suspension with 84% decrease, the other treatments in sterilized soil test caused increases in the final population and reproduction factor of nematode. In non-sterilized soil, all treatments reduced gall and egg masses, but only plantain treatments and some of marigold and caster treatments reduced the reproduction factor of the nematode.

The effects of some micronutrients (iron, zinc and silicon) and macronutrients (nitrogen, phosphorus and potassium) were evaluated on the root-knot nematode, Meloidogyne incognita and plant growth parameters of cucumber (Cucumis sativus cv. Negin) in two independent trials. Each of iron, zinc and silicon micronutrients was used at 5 mg/kg of soil, as iron sequestrene (Fe-EDDHA), zinc sulfate (ZnSO4) and sodium siliconate (Na2O3Si), respectively. Furthermore, nitrogen at 60, 120 and 180 mg/kg, phosphorus at 25, 50 and 75 mg/kg and potassium at 12.5, 25 and 37.5 mg/kg of soil were used as urea, triple superphosphate and potassium sulfate, respectively. At four-leaf stage seedlings, 8000 nematode eggs and juveniles (2 egg and juveniles/gr soil) were added around the roots. After 60-days, data analysis indicated silicon iron, significantly reduced the number of galls/g of root by 55 and 42% compared to control, in the two experiments, respectively, but none of these treatments resulted in significant positive effects on the growth or yield of the studied cucumber cultivar. When macronutrients were evaluated, results showed that N120P25K25 (120 mg/kg of Nitrogen, 25 mg/kg of phosphorus and 25 mg/kg of potassium) and N120P50K25 (120 mg/kg of nitrogen, 50 mg/kg of phosphorus and 25 mg/kg of potassium) significantly reduced the number of galls by 96 and 81% (experiment 3) and 79 and 70% (experiment 4) when compared with control, respectively. These both treatments also improved cucumber growth parameters such as shoot dry and fresh weights, root fresh weight and fruit yield.

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.

Root-knot nematodes (Meloidogyne spp.) are one of the main pests of cucumber production in greenhouses and farms. Applications of chemical and organic fertilizers are effective in reducing the damages caused by these nematodes. For this purpose, during 2013-2014, in an experiment, effects of 25, 50 and 100 mg/kg of elemental sulfur at planting time and 45 days before planting, in sterilized and non-sterilized soil were studied in two turns in greenhouse. First, two eggs or second stage juveniles of the nematode/g of soil and sulfur levels were mixed with the soil. Then cucumber seeds cv. Negin were sown immediately in the half of the pots and in the other half after 45 days. In order to evaluate the effect of sulfur evaporates on the initial nematode population, one half of 45 days pots were placed in plastic bags. The results of two trails showed that sulfur 50 mg/kg of soil in 45 days pots, filled with non-sterilized soil and placed inside plastic bags caused 36% increase in the shoot dry weight and 114% in the yield, on average. In addition, sulfur 100 mg/kg of soil caused 70% and 69% decreases in the final population and reproduction factor of the nematode, respectively.

Morphological observations are made on several populations of Hoplolaimus indicus and Hoplolaimus seinhorsti, recovered from rhizosphere of mango, tamarind, sour orange and sugarcane from the southern regions of Iran. Detailed studies on the two species Hoplolaimus dubius and H. indicus being separated from each other based on some morphological characters, revealed each of them having intra-specific and overlapping variations in morphology and morphometric ranges, enough for not separating two closely related aforementioned species and as a result, H. dubius is considered as a junior synonym of H. indicus. Observations on H. seinhorsti also supported the Siddiqi’s decision on the synonymy of Hoplolaimus sheri with H. seinhorsti. The results of the phylogenetic analyses using D2-D3 expansion segments of 28S rRNA gene were in agreement with the results of previous works, i.e. the classic scheme for assigning species of the genus into two "ancestral" and/or "derived" groups was supported. In phylogenetic trees inferred, using different analysis methods, the Iranian populations of H. indicus were located in the same clade with H. seinhorsti and H. columbus, belonging to "derived" group of species of the genus characterized by having six nuclei in pharyngeal glands, less than four incisures at each lateral field and anteriorly situated position of excretory pore to hemizonid.

Host preference of Helicotylenchus digitiformis Ivanova, 1967 on 10 common field crops including cantaloupe (Samsuri), canola (Golden), clover, corn (704-Hybrid), cotton (Deltapine 16), lucerne (Hamedani), sugar beet (Pb8), tomato (Rutgers), turf grass (Sport) and wheat (Shiraz) was studied in two separate trials. Tests were performed in randomized complete block designs, with initial field populations of 1.49 and 4.33 nematodes/g of soil, under greenhouse conditions. The results showed that all plants are hosts for the nematode but the highest final population and reproduction factor were happened on the cotton (Deltapine 16) and corn (hybrid 704). In addition, to determine the damaging levels of the nematode on corn (hybrid 704) and cotton (Deltapine 16), two tests were conducted in randomized complete block designs with initial field population, ½ field population and control (4.33, 2.16 and Zero nematodes/g of soil, respectively) and six replicates, under greenhouse and microplot conditions. The results showed that all of the field populations under greenhouse conditions and treatments with nematode under microplot conditions caused significantly decreases in most of growth indices of corn plants. Nevertheless, the nematode population has not any significant effect on the growth indices of cotton, although the nematode multiplied on it and reproduction factor was more than one. Also, similar tests were carried out on two local wheat cultivars (Shiraz and Pishtaz), with field population, ½ field population, 1/3 field population and control (1.49, 0.75, 0.50 and Zero nematodes/g of soil, respectively) in a randomized complete block design with five replicates, under microplot conditions. Results showed that only the field population significantly caused decreases in most of growth indices of wheat (Pishtaz).

During a survey conducted in apple orchards of Boyer-Ahmad and Dena regions, in summer of 2013 and 2014, a species of Tylenchus was recovered which was identified as T. naranensisMaqbool, Zarina & Ghazala, 1987 based on morphological and morphometric studies. This is a new report for Iran and describe here. Female: Ventrally curved to C-form, head continuous with body contour, cephalic framework weakly sclerotized with 4 annules, 2.3–3.4 µm high and 5.3–6.6 µm wide. Stylet delicate with conus in 5.3-5.7 µm, about 46–50% of total length, with small rounded to posteriorly directed knobs. Dorsal esophageal gland orifice at 0.8–1.4 µm of stylet base. Body cuticle finely striated, striations 1.0–1.5 µm apart in mid-body; lateral field 4.2–5.4 µm, about 19–26% of body width; four lines in lateral field. Procorpus cylindrical, as long as isthmus; median bulb oval and muscular, located at first half of the esophagus, 6.6–8.5 µm in width, with distinct cuticular thickenings; isthmus slender, nerve ring located at first half of isthmus, 64-86 µm from the anterior extremity. Hemizonid 1–2 annules anterior to excretory pore. Deirids near to excretory pore, 90-106 µm from the head apex.Excretory pore near anterior end of basal bulb; terminal bulb elongated, 8.0–9.5 µm across and 19–25 µm long; Vagina 6–12 µm and 30–40% of vulval body diameter; vulva with projected lips. Ovary outstretched, anteriorly directed with post-vulval uterine sac (7.5-13 µm long, half vulval body length). Tail conoid, ventrally curved with finely rounded tip; phasmid not seen. Morphometric of 14 females is given as below:....

Alfalfa with 78631 hectares area in East Azarbaijan province and approximately 6410 hectares in Ahar region is an important field crop in this area. There was no compre­hensive research about the plant parasitic nematodes associated with alfalfa، therefore during 2002-2003، 33 soil samples were collected from alfalfa fields of several locations in alfalfa fields in Ahar region، partly biodiversity plant parasitic nematodes in this crop were identified. Nematodes were extracted by combined sieving and centrifugal-floatation and were transferred to glycerin method. After preparation، microscopic slides were examined under the light microscope. Measurements and drawing of nematodes were carried out using a drawing tube equipped with the micro­scope. Different species were identified on the basis of morphological characters as well as morphometric parameters and available literature. In this survey، 20 species of 11 genera belonging to suborder Tylenchina included: Boleodorus thylactus، Coslenchus aquaticus، Criconemella antipolitana، Ditylenchus dipsaci، Ditylenchus medicaginis، Geocenamus brevidens، Geocenamus nanus، Geocenamus quadrifer، Helicotylenchus digonicus، Helicotylenchus pseudorobustus، Helicotylenchus، Paratylenchus italiensis، Paratylenchus tateae، Pratylenchus scribneri، Pratylenchus neglectus، Pratylenchus thornei، Psilenchus iranicus، Tylenchorhynchus parvus، Tylenchorhynchus striatus، Zygotylenchus guevarai were identified. Finally، Coslenchus aquaticus and Tylenchorhynchus striatus are new records of plant parasitic nematodes fauna from Iran.

The effect of several levels of DL-β-amino-n-butyric acid (BABA), salicylic acid (SA) and abscisic acid (ABA) on induction of systemic resistance against root-knot nematode, Meloidogyne incognita, in tomato was studied under growth chamber conditions. The experiment was laid out as completely randomized design with three replicates. Tomato (Solanum lycopersicum cv. Moneymaker) was planted in 1 kg plastic pots. At 4-leaf stage, foliar sprays and soil drenches were applied with 0, 0.25, 0.5 and 1 mM of SA and BABA. Foliar spray was also conducted with 0, 50, 100 and 200 µM of ABA. After 24 hours, pots were inoculated each with 1.3 J2 of the nematode per g. of soil. Plant and nematode related parameters were evaluated 60 days after inoculation. The data showed that none of the inducers had significant effect on plant growth indices. On the contrary, different levels of inducers significantly reduced nematode indices including number of galls, egg masses and eggs on root, number of eggs in egg masses and the reproduction factor in induced plants. The reproduction factor decreased about 60% in plants treated with 0.5 mM of SA and BABA and 17% in plants sprayed with 100 mM of ABA.These results indicate that root-knot nematode, M. incognita, can be controlled by application of SA, BABA and ABA, in tomato.

The effect of several rhizobacteria isolates on activity of root-knot nematode, Meloidogyne incognita, was studied under laboratory and greenhouse conditions. Initially, 52 rhizobacteria isolates from the rhizosphere of cucumber, eggplant and tomato plants and their inhibitory effects on egg hatching and mortality of the second stage juveniles (J2s) were investigated in vitro. Then, nine most effective isolates were selected and identified by biochemical and morphological tests. Using filtered culture of five isolates of Pseudomonas fluorescens and one isolate of P. putida, Bacillus subtilis, B. brevis, and Serratia sp., caused 35-48% reduction in egg hatching and 32.2-48.8% increase in the mortality of J2s. The inhibitory effects of the isolates on nematode activity and growth indices of tomato cv. Early Urbana were evaluated under greenhouse conditions. Treatment of the sterilized and non-sterilized field soil and mixture of sand and field soil (3:1 ratio) with suspension of 108CFU ml-1 bacteria and four eggs and J2s of nematode (per g soil) significantly reduced nematode reproduction factor and increased the growth indices of tomato plants. The results showed that nematode indices were reduced more in non-sterilized soil, compared to sterilized soil. The isolates of P. putida, P. fluorescens PF19 and Bacillus subtilis were the most effective isolates in reduction of nematode population.

After studying of the plant parasitic nematodes، collected from different plants and regions of Iran، seven species belong to Paratylenchus، including P. arculatus، P. colinus، P. conicephalus، P. neoprojectus، P. similis، P. straeleni and P. veruculatus were identified. Among them، P. colinus، P. neoprojectus and P. veruculatus are new records for Iranian nematode fauna that full description of them and also that of P. straeleni were given. These species were collected and identified from different hosts and localities as follows: P. colinus from the rhizosphere of apple trees in Divandareh، Kurdistan province، P. neoprojectus from both shade-trees in Tabriz and apricot seedlings in Sanandej، and P. veruculatus from sugarcane fields of Khuzestan province. Furthermore، a dichotomous key for identification of Iranian species of this genus was presented.

The stem and bulb nematode، Ditylenchus dipsaci (Kühn، 1875) Filipjev، 1936 is one the most destructive plant-parasitic nematode which is widely distributed in temperate regions of the world. It is a serious pest on a wide range of crops including lucerne، red clover، sugar beet، maize، onion، garlic، strawberry and many other agricultural and horticultural plants، especially flower bulbs such as narcissus، hyacinth and tulip. Ditylenchus dipsaci has been reported from alfalfa، garlic and onion from Iran. Occurrence of D. dipsaci on strawberry، which was first reported in 1913 from Britain، has not already been observed in Iran. During a survey of the strawberry fields in Bahnamir and Babol cities of Mazandaran province، symptoms of disease including dwarf، leaf shrinkage and deformities، reduced petiole length and surface of lamina، reduced fruit size and reduced fruit setting in severe infections were observed. The nematodes in the soil and aerial parts of the infected strawberry plants were extracted by tray method، fixed and transferred to the anhydrous glycerin. After preparing permanent slides، the nematode was studied by light microscopy. On the basis of morphological and the following morphometric characters، the population extracted from infected strawberry، identified as Ditylenchus dipsaci: Females (n = 10): L = 1169 ± 122 (1011-1411) µm، a = 44. 1 ± 2. 9 (40. 7-51. 0)، b = 6. 3 ± 0. 8 (5. 0-7. 2)، c = 14. 9 ± 1. 6 (13. 2-18. 6)، c'' = 5. 1 ± 0. 4 (4. 6-5. 7)، stylet = 11. 1 ± 0. 7 (10. 2-11. 8) µm، V = 78. 9 ± 2 (74. 5-81. 3). Males (n = 5): L = 1183 ± 175 (947-1430) µm، a = 50. 2 ± 4 (46. 2. -50. 8)، b = 6. 4 ± 0. 8 (5. 8-7. 6)، c = 14. 8 ± 1. 2 (13. 5-16. 2)، c'' = 4. 8 ± 0. 5 (4. 2-5. 5)، stylet = 11. 4 ± 0. 2 (11. 1-11. 6) µm، spicules = 26 ± 1 (24. 8-27) µm، gubernaculum = 7. 7 ± 0. 3 (7. 3-8. 0) µm. Initial investigation indicated that approximately 90% and 40% of 20 and 10 strawberry fields in Bahnamir and Babol cities، respectively، showed the symptoms of disease. The occurrence of disease in different fields was estimated between 20-70%، with respect to the age of cultivation. The average number of nematodes in infected shoots obtained from five plant samples per each field was 147 nematodes per gram of plant tissue.

To identify the faunal parasitic nematodes of Mazandaran, Guilan and Ardebil provinces, roughly 30 soil samples were collected from the rhizosphere of forest trees during 2005-2009. Nematodes were extracted from soil through centrifugal flotation technique. The extracted nematodes were transferred to pure glycerin using common methods. Permanent slides were made and nematodes identified as based on their morphological and morphometric characteristic. Throughout the study, three species of genus Nagelus belonging to family Belonolaimidae were identified viz, N. hehxagrammus, N. neohexagrammus and N. obscuruss from which the second species is introduced as a new record within the nematode fauna of Iran. It could be separated from most closely related species namely N. grandis, N. affinis and N. hexagrammus by its possession of well developed cephalic framework, six annules on head, areolated lateral fields, length of stylet and number of annules on tail.

The effect of rhizosphere bacteria on root-knot nematode (Meloidogyne javanica) was investigated on cucumber under greenhouse conditions. The bacteria were isolated from infected cucumber, tomato and cedar from Garmsar, Marvdasht and Shiraz, as well as cedar, grass and wheat from Bajgah. After sampling, purification, rearing on root of tomato and identification of M. javanica species, the effect of 40 isolates were investigated on hatching (in 3 and 8 days after bacteria inoculation) and the activity of second stage juvenile of the nematode (24, 48 and 72 hours after adding bacteria) in vitro condition. Then 10 best isolates were used on cucumber (Super Amelia) in greenhouse. All isolates increased growth of the plants and decreased the indices of the nematode. Pseudomonas fluorescens CHAO was the most effective isolate and caused about 55.31% and 55.72% reduction in the gall number and also respectively 91.13% and 82.84% reduction in reproduction factor (RF) in the first and second experiments. The second one was an isolate of Pantoea sp. Additionally the effects of P. fluorescens, Bacillus subtilis and Pantoea sp. on the infected cucumber (Super Amelia) to M. javanica, as single application and in combination was tested. The results indicated that using combination of three bacteria are more effective than application of single and combination of two bacteria on increasing growth of plant and reducing indices of the nematode.

In the study of nematode collection of Nematology Laboratory of Tarbiat Modares University, seven species of the family Dolicodoridae belonging to the genera Merlinius, Tylenchorhynchus and Quinisulcius were identified viz, M. bavaricus, M. brevidens, M. plerorbus, T. divittatus, T. goffarti, T. latus and Q. capitatus. Among these species, M. bavaricus, M. plerorbus and T. divitatus are new records for nematodes fauna of Iran. M. bavaricus is distinguished from other species by cephalic skeleton not refractive and fine striae on head and body, thin stylet with rounded knobs, bilobed spermatheca and tail length unstriated terminus. The female characters of Merlinius plerorbus include constricted head, stylet 15-16 µm long, 39-50 µm long tail with 24-32 annules, a smoothly rounded terminus and lobed spermatheca. T. divittatus is distinguished from related species by having lateral fields marked by only three incisures, a well set-off lip region bearing six to seven annuls, stylet 17-20 µm long, presence of a post-anal extension of the intestine and phasmids located behind middle of tail.

Pratylenchus neglectus and P. thornei are the common root-lesion nematodes in irrigated wheat and corn fields in Marvdasht region, Iran. Quiescence of these nematodes in response to water stress (anhydrobiosis) and their return to active stage in wet condition is their important strategy to survive in dried soil. Anhydrobiotic states and infectivity of these two root lesion-nematodes were studied under laboratory, greenhouse, microplats and field conditions. The laboratory results indicated that the highest percentage of quiescent P. thornei became active after the infested dried soil was wetted and kept at 25 °C for 72 hrs. In the greenhouse, 86.3% of P. neglectus were alive in 4 cm air-dried soil layer after 4 months. In microplats, without rainfall the populations of two species remained constant for eight months; however, in plots that received natural rainfalls, the populations of both species were dramatically decreased. Under field conditions, all stages of nematodes survived in anhydrobiotic state. In general, anhydrobiosis is important in relation to population maintenance and survival of root lesion nematodes during winter and summer in Marvdasht region.