مطالعه تغییرات جمعیت نماتد ریشه گرهی در انار تحت شرایط باغ در شهرستان ساوه

Pomegranate is one of the susceptible plants to different species of Meloidogyne spp.. Pomegranate is widely grown in Saveh city and their infestation with these nematodes (M. incognita and M. javanica), management of them is a research priority. Knowing the changes in the nematode population during the year helps to find the best time to control it. Therefore, this research was conducted with the aim of studying the annual fluctuations of the root-knot nematode population in pomegranate under natural conditions in Saveh city. In this study, from one garden in Aghadre village of Saveh city with drip irrigation system, 5 trees with the same root stock (Malas Saveh) and the same age (about 19 years old) were sampled regularly once a month in the middle of the irrigation period. Sampling was done for two consecutive years. Simultaneously with each sampling, soil temperature and humidity were also determined and recorded. After analyzing the population data of nematode eggs and second-stage juveniles in the soil and roots obtained over two years, it was found that the nematode population increased in the conditions of the pomegranate orchards of Saveh city from the beginning of May when the soil temperature reached 20°C and above. in the first year, 6 population peaks were recorded in May, June, July, August, September and November and the highest average population of egg and second stage juvenile of nematode in the soil and roots is 27716 (per 200cm3 of soil and 3g of root) in the average soil temperature of 25.5°C in September. In the second year, 6 population peaks were recorded in the months of May, July, September, November and December and the highest population was recorded 20006 (per 200cm3 of soil and 3g of root) numbers in the soil temperature with an average of 17.5°C in November. This show that in Saveh city conditions, this nematode can be active in the temperature range of 17.5 to 25.5°C and under suitable nutritional and climatic conditions and appropriate soil temperature, has a population peak every 30 to 35 days, indicating the production of one nematode generation. Therefore, the root-knot nematode of pomegranates in the orchards of Saveh can have 6 generations annually.