جستجوی مقالات مرتبط با کلیدواژه "صیفی جات" در نشریات گروه "گیاهپزشکی"

Web spider mites population playing a major pests on vegetable crops during hot summer months. Effectiveness three biomite doses (1, 1.5 and 2 ppm) on cucumber, muskmelon, watermelon in comparison effects of Neem-Azal 1.2% EC, Propargite 570EW, Abamectin 1.8% EC, 1.5 ml/l detergent liquid soap and water sprayed in controlled agent were evaluated against Tetranychus urticae in Esfahan, Khorasan Razavi and Kerman provinces respectively. Complete randomized block designed with three replications used and each replicate consisted at least 50 cultivated plants in each block. Treatment done when at least 5 mobile spider mite stages in 40% randomly collected leaves observed. By random collection of 30 leaves from each treatment determined, effects of them determined at one day before and 3, 7, 14 days after. Collected data converted into mortality% and mean mortality% analysis done with SAS software. Mean spider mite under leaf side of muskmelon in Khorasan Razavi observed 6 to 12 times and 3-5 times higher in Esfahan and Kerman respectively. Highest mean of 61.6 spider mites recorded under sider of muskmelon leaf for 2 ml/l of biomite treatment in Khorasan Razavi. Higher biomite doses effects recorded 73.46% for 2ml/l up to 7 days in Esfahan and 65.56% and 82.67% up to 14 days after recorded in Khorasan Razavi and Kerman without any phtyotoxicity on plant parts in all treatments. Spraying 2 ml/l of biomite at early morning hours under spider mite incidence, provided higher efficiency, longer toxicity period for controlling vegetable spider mites.

Application of botanical-pesticides especially during fructification reduces the health impacts of organic pesticides. Efficacy of different doses of GC-mite (0.3, 0.5 and 1 ml/lit water) with a short pre-harvest interval were investigated in the control of active stages of Tetranychus urticae and Aculops lycopersici in comparison with hexythiazox (10% EC( with the dose of 0.5 ml/lit and abamectin (1.8% EC) with the dose of 0.75 ml/lit on greenhouse cucumber and tomato. Experiment was conducted in a Randomized Complete block design with six treatments and three replications in a long row of 10 to 20 meters of planted crops. Treatments were sprayed when an average of 5 spider mites/under side of cucumber leaf and 10 eriophyid mites/cm2 in the middle portion of underside of tomato leaves were observed. Sampling of live mites was done randomly by collection of 30 leaves from each host plant at the interval periods of one day before and 1day (except cucumber), 3, 7, 14 days after treatments. Statistical analyses of mortality percentage of the treatments were performed by SAS software and grouping was performed by Duncan multiple range test. Although mean mortality% of T. urticae between treatments was not statistically significant (p.0.05) at different intervals, but the mortality% of 0.3 and 0.5 ml/lit of GC-mite increased from 71.48% and 66.66% at day 3 to more than 98% at day 14. The effects of 0.3 and 1 ml/lit of GC-mite in control of A. lycopersici also recorded an increase in mortality% from 60.82% and 67.11% at one day after spraying to 87.08% and 92.90% at 7 days after spraying and decreased at 14th day after spraying. The most suitable and effective spraying time of various doses of GC-mite is at the beginning of the activity of both the pests’ population in the greenhouses.

The pythium spp. are known as the principle agents of seedling blight, damping-off and root rot of cucurbits. This study was performed for determination of Pythium species involved in this diseases as well study their pathogenecity on different cucurbits. The numerous samples were taken at cultivation seasons 2006- 2007 from the fields of cucumber, tomato, egg plant, muskmelon, cucurbit, melon, and watermelon, situated in Mashhad, Chenaran, Ghochan, Fariman, Torbtejam, Gonabad, Kashmar, Khvaf, Neishboor, Sabzevar, Torbateheydarieh, Kalat, Dargaz, Sarakhs, and Taibad (North East of Iran). sixty pythium isolates were obtined from the diseased samples in total. They were identified based on morphological and micrometric characteristics. The results showed that 46. 44% are belonging to the P. ultimum var. ultimum, 16. 66% to the P. aphanidermatum, 13. 33% to the P. amasculinum, 10% to the Pythium Group HS, 16. 6. 66% to P. oliganderum, 3. 33% to the P. paroecondrum, and 3. 33% to the P. echinulatum. The P. amasculinu، P. echinulatum and P. paroecondrum are the first report from Iran. The Pythium Group HS and P. oliganderum are also the first report from cucurbits in Iran. The pathogenesity test of isolates showed that P. ultimum var ultimum، Pythium Group HS، P. paroecondrum، P. aphanidermatum and P. echinulatum are pathogenic on cucumber, tomato, egg plant, muskmelon, cucurbit, melon, and watermelon, while P. amasculinum was not Pathogenic on melon and cucurbit.