coccinellids play a major role in aphid control. hippodamia variegata goeze is an aphidophagous predator of worldwide distribution that could be found in different parts of iran. one of the criteria for evaluating the efficiency of a predator is its response to change in prey population density (functional response). the functional responses of males and females of hippodamia variegata were stu...

in order to study different arrangements and weed controls effects on mung bean (vigna radiate l. wilczek) – black cumin (nigella sativa l.) intercropping an experiment was conducted at the research station of faculty of agriculture, ferdowsi university of mashhad, iran, during growing season 2005 – 2006. sixteen treatments comprising combinations of eight sowing patterns [a1: sole black cumin,...

Beginning in 2000, snap bean (Phaseolus vulgaris L.) crops exhibiting virus-like symptoms on the foliage (leaf distortion, yellow and green mottling, and mosaic) were increasing in frequency on a regional scale across the northern United States and Canada (10,20). These crops also produced fewer pods or pods that were either twisted or necrotic (hence unmarketable). Across the Midwest and north...

in several parts of the world, important yield losses are caused to faba bean due to attack by the black bean aphid aphis fabae scopoli. although resistance could be a good alternative to chemical control, its genetic basis is still largely unknown; and its phenotypic expression is still poorly described, making crucial the permanent evaluation of genetic resources available in different countr...

Although bell bean is a true vetch, it differs greatly from other vetches with its strong upright growth. It also has a relatively shallow, thick taproot, which may be useful for opening up heavy soils. Bell bean is often used in mixes with vetches, peas, or cereals. Because of its height and because it does not tolerate close mowing, it is often omitted from mixes in frost-prone areas. Bell be...

The aphid-ant mutualistic relationships are not necessarily obligate for neither partners but evidence is that such interactions provide them strong advantages in terms of global fitness. While it is largely assumed that ants actively search for their mutualistic partners namely using volatile cues; whether winged aphids (i.e., aphids' most mobile form) are able to select ant-frequented areas h...

The bacterial communities of aphids were investigated by terminal restriction fragment length polymorphism and denaturing gradient gel electrophoresis analysis of 16S rRNA gene fragments generated by PCR with general eubacterial primers. By both methods, the gamma-proteobacterium Buchnera was detected in laboratory cultures of six parthenogenetic lines of the pea aphid Acyrthosiphon pisum and o...