جستجوی مقالات مرتبط با کلیدواژه « climate condition » در نشریات گروه « گیاهپزشکی »

High temperatures and low-humidity are the favorable conditions for spider mites, Tetranychus urticae Koch and Schizotetranychus smirnovi Wainstein, to cause serious threat to quality and quantity of almond. This study was undertaken to understand population changes of the spider mites during the normal and dry years and to predict the possibility of the pest outbreak in order to develop a successful integrated management strategy. Population fluctuations of S. smirnovi and T. urticae were studied on almond (Mamaei variety), from April to October of 2007-2009, in Saman orchards, Chaharmahal va Bakhtiari province, Iran. Meteorological data of three nearest synoptic stations including Saman, Zaman khan and Shahre-kord were collected from the Chaharmahal va Bakhtiari meteorological organization. The Standardized Precipitation Index (SPI) was used to detect meteorological droughts based on the monthly rainfall input data of three synoptic stations. The results showed the year 2008 as an extremely dry year, while revealing 2007 and 2009 as normal years. Comparison of spider mite population density in this year (SPI < -2) with the normal years, 2007 (SPI = -0.53) and 2009 (SPI= 0.41), showed a significant increase in the population density of, S. smirnovi, (14.65 and 2.95 times) and T. urticae (7.28 and 2.87 times) compared to 2007 and 2009, respectively. Spearman’s correlation analysis showed significant negative correlation of mean precipitation with population density of, S. smirnovi, (r = -0.65, p=0.022), T. urticae (r = -0.73, p=0.0001), and the predatory thrips, Scolothrips longicornis Priesner, (r = -0.67, p=0.0001) during three studied years. In the drought year, the phytophagous mite’s population increased in response to high temperatures and low humidity. In a such year, the almond trees can be more vulnerable to mite damages and control is necessary.

Potato tuber moth, Phthorimea operculella, is one of the most important pests of potato in Iran. Biology of the pest on two commercial potato cultivars, Sante and Arinda, was studied in Andimeshk, north of Khuzestan province, Iran. Samplings were weekly performed from two separate fields cultivated by two cultivars during two agricultural seasons (2013-2015). Adults and immatures monitoring were done by using sex pheromone trap and direct count respectively. Results showed that adults occurred with two months difference in the first and second agricultural seasons which is related to different means temperature in the two studied seasons. Significant correlation was observed between adult densities and weekly means temperature. First adults appeared on both cultivars in early February and December in the first and second agricultural seasons and peaked at the end of March, respectively. The peaks of egg number were observed at The end of March for the first and second agricultural seasons, respectively. First larvae were observed in early and mid of March in the first and second years. Larvae peaked at The end of March and mid of April for the first and second years, respectively. No considerable difference was observed among occurrence, peak and activity time of the developmental stages of potato tuberworm on The two tested cultivars.