نشریه گیاه پزشکی کاربردی
سال هشتم شماره 1 (پیاپی 25، شهریور 1398)

In order to identify the plant parasitic nematodes, some soil and root tissues of plants samples were collected from different crops in of Eshtehard and Nazarabad, Alborz province, through 2017-8. After transferring the samples to the laboratory, soil and root washing operations, nematode extraction, transferring and fixing in pure glycerin were performed. Permanent microscopic slides and incisions were made from different parts of the body of some species. After microscopic observations, the necessary measurements and drawing of the required images, the extracted species were identified using different keys. During the survey and morphological studies, six nematode species of three genera were identified as follows: Aphelenchus avenae, Paraphelenchus myceliophthorus, Aphelenchoides centralis, Aphelenchoides fuchsi, Aphelenchoides parabicaudatus, Aphelenchoides varicaudatus Among the identified nematodes, the species Aphelenchoides fuchsi is reported for the first time in Alborz province and for the second time in the world. Aphelenchoides varicaudatus is also reported for the second time in Iran.

Native strains of Bacillus thuringiensis (Bt) were isolated from forest soils of the different areas of Golestan Province and Cry and Vip genes, responsible of the effective toxin, were monitored. From a total of 42 soil samples examined through selective sodium acetate detention, 160 Bt isolates were separated. After planting the colonies, specific staining and microscopic identification were observed in 40% of isolates crystalline proteins that are toxic to many insects. Molecular study showed that in 12 isolates, gene Cry1 existed. Genetic structure tests for presence of 3 gene Cry1A (including Cry1Ac, Cry1Ab, Cry1Aa) and genes Cry1I, Cry1F, Cry2, Cry 9, Vip3Aa was carried out using the 8 pair of specific primers. Genes Cry1Ab, Cry2, Cry F were observed in all isolates, but the genes of Cry1Aa, Cry1I, Cry1Ac had very low frequency (Lower than 20%) or not found in any of the isolates. The results of this research could be very useful for tracking native Bt isolates that contain effective crystalline proteins for insects

During the growing seasons of the years 2013-2014, Alborz, Mazandaran, Markazi and Tehran provinces were surveyed to assess the distribution of PNRSV and ToRSV in rose plants, field bindweed and common sow thistle weeds grown nearby the sampled roses. A total numbers of 600 symptomatic and asymptomatic rose leaves and 50 weeds were sampled. Using with the DAS-ELISA serological test, samples were tested. Results indicated that roses are infected to PNRSV with the infection rates of 39.24%, 30.7%, 44.8% and 38.1% and to ToRSV with the infection rates of 38%, 25.6%, 32.3% and 28.3% through in Tehran, Alburz, Mazandaran and Markazi respectively.  It was also revealed that PNRSV and ToRSV was respectively 26% and 18% incidence in weeds. Infected samples were mechanically inoculated on herbaceous propagative and indicator plants using with the potassium phosphate buffer pH 7.1 containing the antioxidant materials. To confirm the presence of viral infections in diseased roses and indicator plants, infected plants were analyzed by RT-PCR, using PNRSV-specific primers to amplify a related portion of the PNRSV and ToRSV genomes. Those infected samples have positively reacted with the both specific primers and desired DNA fragments with the size of about 210bp for the coat protein of PNRSV and 500bp for the polymerase of ToRSV were amplified for them. By this research and for the first time, presence of PNRSV and ToRSV in rose plant and herbaceous weeds was assessed.

Watermelon with a vast area of cultivation is one of the most important products of the North Khorasan Province and the city of Esfarayen. In these areas, Tetranychus urticae can be considered as one of the most important pests of this product; the uncontrolled use of chemical pesticides causes the population to become resistant to pesticides and remains; poisons are very important for their fresh food; Plant nutrition quality hosts a factor influencing pest growth and reproduction. In order to investigate the effect of nutrition in field conditions on different biological stages of T. urticae, an experiment in the form of a randomized complete block design with seven treatments (chicken manure, cow manure, sheep manure, NPK, NPK + Humic acid, Humic acid and control) in Three sampling times were performed in 2015 in Esfarayen city. The results showed that the largest population of T. urticae in chicken manure on biological stages (egg, larva, nymph and adult), respectively, with an average (34.1 ± 27.12, 78.1 ± 04.12, 35.1 ± 04 . 8 and 69.1 ± 73.12) and the lowest number in the NPK + Humic acid fertilizer granulation in biological stages (egg, larva, nymph and adult), respectively (67.0 ± 16.4, 55.0 ± 88.2, 38.0 ± 18.2 and 67.0 ± 07.5) was observed. The results of this research granular fertilizer treatment Humic acid and Humic acid + NPK granulated onion fields in order to control the two-spotted spider mite is considered