aphids in unsprayed canola (brassica napus linnaeus) fields in isfahan province (central iran) were sampled for two growing seasons, 2011-2013. sampling unit was a whole plant and 20 plants were sampled weekly. in the laboratory, heat-extracting and sub-sampling techniques were used to estimate the density of aphids. to determine the relationship between population growth rate of the aphids and...

Laboratory bioassays were done to determine the level of resistance to endosulfan, cypermethrin, deltamethrin, methamidophos, profenofos and chlorpyrifos in field populations of cabbage aphid, Brevicoryne brassicae (L). Comparison between Multan and Kabirwala strains revealed that the level of resistance in Multan strain was comparatively higher to methamidophos, profenofos and chlorpyrifos as ...

Rapeseed (Brassica napus L. ssp. oleifera Metzg) is attacked by a wide range of pests. Breeding resistant cultivars one the best methods protecting crops against insects, and non-cultivated species Brassicaceae can be used as resistance donors. In this study, we investigated relationship between nutrient content to two commonly occurring pests (Delia radicum Brevicoryne brassicae) in 12 hybrid ...

1. Plants are frequently under attack by multiple insect herbivores, which may interact indirectly through herbivore-induced changes in the plant's phenotype. The identity, order, and timing of herbivore arrivals may influence the outcome of interactions between two herbivores. How these aspects affect, in turn, subsequently arriving herbivores that feed on double herbivore-induced plants has n...

Induced plant defence in response to phytophagous insects is a well described phenomenon. However, so far little is known about the effect of induced plant responses on subsequently colonizing herbivores in the field. Broccoli plants were induced in the belowground compartment using (i) infestation by the root-herbivore Delia radicum, (ii) root application of jasmonic acid (JA) or (iii) root ap...

biological characteristics of chrysoperla carnea (stephen.) fed on hyalopterus pruni (goff), brevicoryne brassicae (l.) and aphis pomi (degeer) were studied under laboratory conditions. developmental time of c.carnea on the above mentioned aphids were 24.75, 25.77 and 30.75 days, respectively. preimeainal mortality was 60.69, 43.75 and 63.1%, respectively. female longevity of c.carnea was equal...