Numerical taxonomy was used for identification and grouping of the genera, species, and populatio... more Numerical taxonomy was used for identification and grouping of the genera, species, and populations in the families Merliniidae and Telotylenchidae. The variability of each of 44 morphometric characters was evaluated by calculation of the coefficient of variability (CV) and the ratio of extremes (max/min) in the range of 1,020 measured females. Also correlation and regression analyses were made between characters to find potential collinearities. Hierarchical cluster analysis (HCA) was used for (i) grouping 21 genera in the superfamily Dolichodoroidea based on literature data coded for states of 18 diagnostic characters, and (ii) for grouping Iranian populations belonging to selected genera. Furthermore, STEPDISC analysis was used for (i) grouping 11 genera of Merliniidae and Telotylenchidae based on the measurements of 35 characters from 1,007 Iranian female specimens, and (ii) grouping measured females of eight species of Amplimerlinius and Pratylenchoides. The multivariate data a...
In order to identify the Aphelenchina species nematodes of crop plants, 250 soil samples were col... more In order to identify the Aphelenchina species nematodes of crop plants, 250 soil samples were collected from different fields in Jiroft and Kahnoj regions, Kerman province. The nematodes were extracted from soil by centrifugal flotation technique. The extracted nematodes were transferred to glycerin. The permanent slides were mounted. The nematodes were identified by morphological and morphometrical characters. In this study nine species of three genera Aphelenchoides, Aphelenchus and Paraphelenchus from suborder Aphelenchina were identified viz, Aphelenchoides. astrecaudatus, A. curiolis, A. limberi, A. obtosicaudatus, A. parabicaudatus, A. sacchari, A. spicomucronatus, Aphelenchus avenae and Paraphelenchus. amblyurus. Among these species Aphelenchoides curiolis, A. obtusicaudatus and Paraphelenchus amblyurus is reported from Iran for the first time.
Two assays were carried out in Badjgah, Fars province, the south of Iran, with the purpose of est... more Two assays were carried out in Badjgah, Fars province, the south of Iran, with the purpose of establishing the development time of Heterodera filipjevi life cycle phases in wheat roots and also to study the effect of the certain cereals including bread wheat, durum wheat, barley, corn and millet on the nematode population densities. Results of field microplots showed that hatching of eggs was occurred at 2-6 °C. The second stage juveniles (J2) were observed in the roots within periods with 13 °C average temperature and with no precipitation. Juveniles (J3) and (J4) were appeared within the roots at 110 and 120 days after penetration, respectively. The white females adhered to the roots and males in soil were found 7 and 14 days later, respectively. Cyst formation occurred about two months after observing white females; In short, the process of H. filipjevi development was completed during 197 days. Results of greenhouse assay showed that the studied nematode species reproduced best ...
In this research the comparison among capability of some microelements to decrease Cereal Cyst Ne... more In this research the comparison among capability of some microelements to decrease Cereal Cyst Nematode population and increasing wheat yield were investigated. The treatment included: 0.1 g urea, 0.2 g,potassium sulfate, 0.1 g super phosphate, 0.1 zinc sulfate, 0.1 urea + 0.1 zinc sulfate,0.1 urea + 0.1 g super phosphate, 0.1 g urea + 0.2 potassium sulfate, 0.1 g super phosphate + 0.2 g potassium sulfate, 0.1 g zinc sulfate + 0.1 super phosphate, 0.1 g zinc sulfate + 0.2 g potassium sulfate and combination of all fertilizer with fertilizer calculate critical levels in the field based on physical and chemical analysis. In completely randomized complete block design pattern with three replication in greenhouse conditions was designed. Statistical analysis showed that the treatment in this experiment to see each other and control have a significant impact on both cases so that the minimal contamination by counting the average number of cysts/100 g soil and number of eggs and j2 per gr...
Soil samples collected from different plants and localities in Iran yielded one new and three kno... more Soil samples collected from different plants and localities in Iran yielded one new and three known species of the genus Geocenamus with tessellated cuticle. Geocenamus conicaudatus n. sp. is characterised by a hemispherical cephalic region, set-off from the rest of body by a constriction, a slender stylet 17-20 µm long with laterally directed knobs, coarsely annulated cuticle with 32-34 longitudinal striae and a conical tail with smooth, finely rounded terminus. Morphological and molecular studies on the populations of G. paniculoides and G. tartuensis indicated that G. paniculoides may be considered as a valid species. Intraspecific variability of some characters of 30 Iranian populations of G. rugosus were studied. An identification key to 32 valid species of the genus Geocenamus is given.
Summary - Three teratocephalid species, viz. Teralocephalus lirellus, EweralOcephalus palustris, ... more Summary - Three teratocephalid species, viz. Teralocephalus lirellus, EweralOcephalus palustris, and MelaleralOCephaluscrassidens, were found in the rhizosphere ofwild and cultivated plants in the Province of Hamadan in the West of Iran. Two Iranian popu lations of T lirellus were compared with a Belgian population of the same species, kept in culture. Light and scanning electron microscopy of these species provided
Plant samples infected with Ditylenchus dipsaci were collected from alfalfa and garlic fields in ... more Plant samples infected with Ditylenchus dipsaci were collected from alfalfa and garlic fields in different regions of Iran. The nematodes were cultured on monoxenic carrot discs to obtain sufficient inocula. The host ranges of three garlic populations were tested on garlic, onion, fababean, common bean, sugar beet, pea and soybean. Alfalfa, Melilotus sp., common bean, clover, onion, garlic and sainfoin (Onobrychis viciaefolia Scop.) were tested with four alfalfa populations of D. dipsaci. The plants were inoculated with 200 D. dipsaci in 10µl of 1% CMC (Carboxymethyl cellulose) suspension, maintained in growth chamber at 20°C±2 for 16-hour light and 8-hours dark period, and high humidity was sustained for one week. The plants were harvested after eight weeks (some after four weeks) and the above ground parts were examined. The results indicated that onion and garlic were suitable hosts, pea and sugar beet and common bean (in two populations) poor hosts but Soybean was not a host for...
Seven species belonging to the genus Coslenchus were found in soil samples collected from the rhi... more Seven species belonging to the genus Coslenchus were found in soil samples collected from the rhizosphere of plants in cultivated or natural habitats in western Iran. C. japonicus Mizukubo et Minagawa, 1984 and C. polygyrus Bajaj et Bhatti, 1983 were found for the first time since their descriptions. These species, along with C. multigyrus Siddiqi, 1981, C. franklinae Siddiqi, 1981 and C. polonicus Brzeski, 1982, are new records for Iran. LM and SEM show the variable number of longitudinal lines in the lateral field of the first two species. Also the number of longitudinal ridges varies from 26 to 30 in C. polygyrus, and 19 to 26 in C. polonicus.
Trois espèces de Tératocephalides, #Teratocephalus lirellus$, #Euteratocephalus palustris$ et #Me... more Trois espèces de Tératocephalides, #Teratocephalus lirellus$, #Euteratocephalus palustris$ et #Metateratocephalus crassidens$ ont été récoltées dans la rhizosphère de plantes sauvages et cultivées dans la Province d'Hamadan dans l'Ouest de l'Iran. Deux populations iraniennes de #T. lirellus$ sont comparées avec une population belge en culture. L'étude de ces espèces en microscopie photonique et électronique a produit de nouvelles informations intéressantes. Des photos en microscopie électronique à balayage de zones fracturées de la cuticule d'#E. palustris$ ont montré des structures intracuticulaires plus ou moins en forme de fleur, structures qui ressemblent à celles identifiées chez #Achromadora micoletzkyi$ et #A. semiarmata$. #Euteratocephalus spiraloides$ est synonymisé avec #E. palustris$. Ces espèces sont identifiées pour la première fois en Iran. (Résumé d'auteur)
One new and one known species of the genus Stegelletina and three species of the genus Cervidellu... more One new and one known species of the genus Stegelletina and three species of the genus Cervidellus were found in soil samples from Iran. Stegelletina kheirii sp. n. is characterized by its convex-conoid tail with subacute terminus and by its anterior structure: labial probolae slender-conical with a single bifurcation, primary axils with single triangular guarding piece appearing as two refractive V-shaped elements, lip margins in secondary axils with four pairs of rounded tines, without refractive elements. S. kheirii sp. n. is close to S. similis and S. devimucronata but differs from both mainly in the shape of the tail terminus and absence of a V-shaped element in each secondary axil. Scanning electron microscopic study of C. neftasiensis and C. vexilliger showed that the extension of the lateral field on the tail and width of the phasmid opening are variable characters. S. devimucronata and C. cancellatus were also found and described here.
The sample size or the number of small fields to be sampled for root lesion nematodes was estimat... more The sample size or the number of small fields to be sampled for root lesion nematodes was estimated using CV as a measure of reliability and Taylor’s power law model as a descriptor of nematode spatial distribution in the irrigated wheat fields of Marvdasht region, in autumn 2006. Fifty-six fields were sampled following eight different sampling patterns including: 1-2, sampling the first and the second diagonal transects (D1 and D2 transects, respectively), 3-4, sampling in a line along/across cultivation rows in the middle of field (D3/D4 transects), 5, taking a composite sample from D1 to D4 (Mixed transect), 6-8, the average of D1 to D4 transects (D1-4), D1 and D2 transects (D1-2) and D3 and D4 transects (D3-4), respectively. The number of samples for estimation of population densities of root lesion nematodes with 85% reliability (the most reasonable reliability level for management decisions) were greatest for D3 and D4 patterns (73 and 72 fields, respectively) and smallest for...
Numerical taxonomy was used for identification and grouping of the genera, species, and populatio... more Numerical taxonomy was used for identification and grouping of the genera, species, and populations in the families Merliniidae and Telotylenchidae. The variability of each of 44 morphometric characters was evaluated by calculation of the coefficient of variability (CV) and the ratio of extremes (max/min) in the range of 1,020 measured females. Also correlation and regression analyses were made between characters to find potential collinearities. Hierarchical cluster analysis (HCA) was used for (i) grouping 21 genera in the superfamily Dolichodoroidea based on literature data coded for states of 18 diagnostic characters, and (ii) for grouping Iranian populations belonging to selected genera. Furthermore, STEPDISC analysis was used for (i) grouping 11 genera of Merliniidae and Telotylenchidae based on the measurements of 35 characters from 1,007 Iranian female specimens, and (ii) grouping measured females of eight species of Amplimerlinius and Pratylenchoides. The multivariate data a...
In order to identify the Aphelenchina species nematodes of crop plants, 250 soil samples were col... more In order to identify the Aphelenchina species nematodes of crop plants, 250 soil samples were collected from different fields in Jiroft and Kahnoj regions, Kerman province. The nematodes were extracted from soil by centrifugal flotation technique. The extracted nematodes were transferred to glycerin. The permanent slides were mounted. The nematodes were identified by morphological and morphometrical characters. In this study nine species of three genera Aphelenchoides, Aphelenchus and Paraphelenchus from suborder Aphelenchina were identified viz, Aphelenchoides. astrecaudatus, A. curiolis, A. limberi, A. obtosicaudatus, A. parabicaudatus, A. sacchari, A. spicomucronatus, Aphelenchus avenae and Paraphelenchus. amblyurus. Among these species Aphelenchoides curiolis, A. obtusicaudatus and Paraphelenchus amblyurus is reported from Iran for the first time.
Two assays were carried out in Badjgah, Fars province, the south of Iran, with the purpose of est... more Two assays were carried out in Badjgah, Fars province, the south of Iran, with the purpose of establishing the development time of Heterodera filipjevi life cycle phases in wheat roots and also to study the effect of the certain cereals including bread wheat, durum wheat, barley, corn and millet on the nematode population densities. Results of field microplots showed that hatching of eggs was occurred at 2-6 °C. The second stage juveniles (J2) were observed in the roots within periods with 13 °C average temperature and with no precipitation. Juveniles (J3) and (J4) were appeared within the roots at 110 and 120 days after penetration, respectively. The white females adhered to the roots and males in soil were found 7 and 14 days later, respectively. Cyst formation occurred about two months after observing white females; In short, the process of H. filipjevi development was completed during 197 days. Results of greenhouse assay showed that the studied nematode species reproduced best ...
In this research the comparison among capability of some microelements to decrease Cereal Cyst Ne... more In this research the comparison among capability of some microelements to decrease Cereal Cyst Nematode population and increasing wheat yield were investigated. The treatment included: 0.1 g urea, 0.2 g,potassium sulfate, 0.1 g super phosphate, 0.1 zinc sulfate, 0.1 urea + 0.1 zinc sulfate,0.1 urea + 0.1 g super phosphate, 0.1 g urea + 0.2 potassium sulfate, 0.1 g super phosphate + 0.2 g potassium sulfate, 0.1 g zinc sulfate + 0.1 super phosphate, 0.1 g zinc sulfate + 0.2 g potassium sulfate and combination of all fertilizer with fertilizer calculate critical levels in the field based on physical and chemical analysis. In completely randomized complete block design pattern with three replication in greenhouse conditions was designed. Statistical analysis showed that the treatment in this experiment to see each other and control have a significant impact on both cases so that the minimal contamination by counting the average number of cysts/100 g soil and number of eggs and j2 per gr...
Soil samples collected from different plants and localities in Iran yielded one new and three kno... more Soil samples collected from different plants and localities in Iran yielded one new and three known species of the genus Geocenamus with tessellated cuticle. Geocenamus conicaudatus n. sp. is characterised by a hemispherical cephalic region, set-off from the rest of body by a constriction, a slender stylet 17-20 µm long with laterally directed knobs, coarsely annulated cuticle with 32-34 longitudinal striae and a conical tail with smooth, finely rounded terminus. Morphological and molecular studies on the populations of G. paniculoides and G. tartuensis indicated that G. paniculoides may be considered as a valid species. Intraspecific variability of some characters of 30 Iranian populations of G. rugosus were studied. An identification key to 32 valid species of the genus Geocenamus is given.
Summary - Three teratocephalid species, viz. Teralocephalus lirellus, EweralOcephalus palustris, ... more Summary - Three teratocephalid species, viz. Teralocephalus lirellus, EweralOcephalus palustris, and MelaleralOCephaluscrassidens, were found in the rhizosphere ofwild and cultivated plants in the Province of Hamadan in the West of Iran. Two Iranian popu lations of T lirellus were compared with a Belgian population of the same species, kept in culture. Light and scanning electron microscopy of these species provided
Plant samples infected with Ditylenchus dipsaci were collected from alfalfa and garlic fields in ... more Plant samples infected with Ditylenchus dipsaci were collected from alfalfa and garlic fields in different regions of Iran. The nematodes were cultured on monoxenic carrot discs to obtain sufficient inocula. The host ranges of three garlic populations were tested on garlic, onion, fababean, common bean, sugar beet, pea and soybean. Alfalfa, Melilotus sp., common bean, clover, onion, garlic and sainfoin (Onobrychis viciaefolia Scop.) were tested with four alfalfa populations of D. dipsaci. The plants were inoculated with 200 D. dipsaci in 10µl of 1% CMC (Carboxymethyl cellulose) suspension, maintained in growth chamber at 20°C±2 for 16-hour light and 8-hours dark period, and high humidity was sustained for one week. The plants were harvested after eight weeks (some after four weeks) and the above ground parts were examined. The results indicated that onion and garlic were suitable hosts, pea and sugar beet and common bean (in two populations) poor hosts but Soybean was not a host for...
Seven species belonging to the genus Coslenchus were found in soil samples collected from the rhi... more Seven species belonging to the genus Coslenchus were found in soil samples collected from the rhizosphere of plants in cultivated or natural habitats in western Iran. C. japonicus Mizukubo et Minagawa, 1984 and C. polygyrus Bajaj et Bhatti, 1983 were found for the first time since their descriptions. These species, along with C. multigyrus Siddiqi, 1981, C. franklinae Siddiqi, 1981 and C. polonicus Brzeski, 1982, are new records for Iran. LM and SEM show the variable number of longitudinal lines in the lateral field of the first two species. Also the number of longitudinal ridges varies from 26 to 30 in C. polygyrus, and 19 to 26 in C. polonicus.
Trois espèces de Tératocephalides, #Teratocephalus lirellus$, #Euteratocephalus palustris$ et #Me... more Trois espèces de Tératocephalides, #Teratocephalus lirellus$, #Euteratocephalus palustris$ et #Metateratocephalus crassidens$ ont été récoltées dans la rhizosphère de plantes sauvages et cultivées dans la Province d'Hamadan dans l'Ouest de l'Iran. Deux populations iraniennes de #T. lirellus$ sont comparées avec une population belge en culture. L'étude de ces espèces en microscopie photonique et électronique a produit de nouvelles informations intéressantes. Des photos en microscopie électronique à balayage de zones fracturées de la cuticule d'#E. palustris$ ont montré des structures intracuticulaires plus ou moins en forme de fleur, structures qui ressemblent à celles identifiées chez #Achromadora micoletzkyi$ et #A. semiarmata$. #Euteratocephalus spiraloides$ est synonymisé avec #E. palustris$. Ces espèces sont identifiées pour la première fois en Iran. (Résumé d'auteur)
One new and one known species of the genus Stegelletina and three species of the genus Cervidellu... more One new and one known species of the genus Stegelletina and three species of the genus Cervidellus were found in soil samples from Iran. Stegelletina kheirii sp. n. is characterized by its convex-conoid tail with subacute terminus and by its anterior structure: labial probolae slender-conical with a single bifurcation, primary axils with single triangular guarding piece appearing as two refractive V-shaped elements, lip margins in secondary axils with four pairs of rounded tines, without refractive elements. S. kheirii sp. n. is close to S. similis and S. devimucronata but differs from both mainly in the shape of the tail terminus and absence of a V-shaped element in each secondary axil. Scanning electron microscopic study of C. neftasiensis and C. vexilliger showed that the extension of the lateral field on the tail and width of the phasmid opening are variable characters. S. devimucronata and C. cancellatus were also found and described here.
The sample size or the number of small fields to be sampled for root lesion nematodes was estimat... more The sample size or the number of small fields to be sampled for root lesion nematodes was estimated using CV as a measure of reliability and Taylor’s power law model as a descriptor of nematode spatial distribution in the irrigated wheat fields of Marvdasht region, in autumn 2006. Fifty-six fields were sampled following eight different sampling patterns including: 1-2, sampling the first and the second diagonal transects (D1 and D2 transects, respectively), 3-4, sampling in a line along/across cultivation rows in the middle of field (D3/D4 transects), 5, taking a composite sample from D1 to D4 (Mixed transect), 6-8, the average of D1 to D4 transects (D1-4), D1 and D2 transects (D1-2) and D3 and D4 transects (D3-4), respectively. The number of samples for estimation of population densities of root lesion nematodes with 85% reliability (the most reasonable reliability level for management decisions) were greatest for D3 and D4 patterns (73 and 72 fields, respectively) and smallest for...
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