نوع مقاله : مقاله پژوهشی
نویسندگان
1 استادیار، گروه گیاه‌پزشکی دانشکدۀ کشاورزی، دانشگاه کشاورزی و منابع طبیعی رامین، ملاثانی، اهواز
2 استادیار گروه گیاه‌پزشکی دانشکدۀ کشاورزی، دانشگاه کشاورزی و منابع طبیعی رامین، ملاثانی، اهواز
چکیده
کلیدواژه‌ها
عنوان مقاله [English]
نویسندگان [English]
Population dynamics and spatial distribution of two harmful species of Thysanoptera
prevalent on cereal crops (Thrips tabaci Lindman, 1888 and Haplothrips tritici Kurdjomove,
1912), were investigated during 2009-2011. Weekly sampling was carried out in a one hectar
of wheat field in Ramin University of Khuzestan, South-West of Ahvaz. Spatial distribution of
immature as well as adults of either species was investigated throughTaylor’s power law and
Iwao’s patchiness regression methods. The results revealed that the population peak for either
species occurs in late March and on the first to middle of April respectively for adults and for
larvae. Results of correlation between population dynamics (larval and adult stages) and the
factors temperature and precipitation revealed that thereis positive vs negative correlations
between population fluctuation and the factors of temperature vs humidity. An investigation of
the spatial distribution throughTaylor’s power law and Iwao’s patchiness regression method
indicated that larval stage and total stages in both species are clumped. Based upon R2 and F of
regression analysis, Iwaos patchiness provided a more adequate description of spatial
distribution than Taylor’s power law for either of the species. Because the seasonal peak in
these two species' density corresponded with the period of peak bloom, thus, in order to study
the population dynamics, the earing stage is the most suitable for sampling the thrips on wheat.
کلیدواژه‌ها [English]
)
