This research was carried out for evaluating phenotypic diversity and traits correlation in 60 almond genotypes and cultivars in nursery conditions. After preparation land and the bitter seeds of Shahroud22 genotype as seedling rootstocks planted in the autumn 2005. After the seed germination in the spring of the next year, the results of recorded data in 3rd may of 2006 showed that the planted...

Maize (Zea mays L.) is a staple crop worldwide with extensive genetic variations. Various insects attack maize plants causing large yield loss. Here, we investigated the responses of maize B73, a susceptible line, and Mo17, a resistant line, to the aphid Rhopalosiphum padi on metabolite and transcriptome levels. R. padi feeding had no effect on the levels of the defensive metabolites benzoxazin...

The pea aphid, Acyrthosiphon pisum (Harris) (Hemiptera: Aphididae), shows wing polyphenism (winged and wingless morphs) in its life cycle. The winged morph is adapted for dispersal; its two developmental adult stages (for dispersal and reproduction) are based on its breeding periods. The two morphs show different phototactic behavior and the winged can change its preference to light according t...

In the north central United States, populations of the exotic soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), are highly variable across space, complicating effective aphid management. In this study we examined relationships of plant nutrients, landscape structure, and natural enemies with soybean aphid abundance across Iowa, Michigan, Minnesota, and Wisconsin, representing the ...

Luminescent signals can be used by animals for a number of purposes, including courtship and defense, sometimes by the same individual. However, the relative costs of producing these different behaviors are largely unknown. In the marine ostracod Photeros annecohenae, males utilize extracellular luminescence for complex courtship displays, and both males and females luminesce as a predation def...

Crops transformed to express Bacillus thuringiensis (Bt) toxins can cause close to 100% mortality of certain target pest species. This study assessed the effect of target pest reduction on the predatory insect Chrysoperla carnea (Stephens) in the presence of alternative prey. Numbers of lacewings recovered from Bt oilseed rape (cultivar Oscar, event O52) did not differ significantly from number...

The soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is native to Asia and was recently (2000) detected in North America. Since then, it has become a significant threat to U.S. soybean production. Although neonicotinoid insecticide seed treatments, imidacloprid and thiamethoxam, have been suggested as a method of control, the season-long efficacy is still uncertain. Therefore, th...

Host-searching and oviposition behaviors of parasitoids, and defensive responses of the hosts, are fundamental in shaping the ecology of host-parasitoid interactions. In order to uncover key behavioral features for the little known interactions between phorid parasitoids (Diptera: Phoridae) and their leaf-cutting ant hosts (Formicidae: Attini), host-related behavioral strategies (i.e., host sea...

yellow, and even drop. Other symptoms of direct feeding damage include plant stunting, poor pod fill, reduced Since 2000, the soybean aphid (Aphis glycines Matsumura) has pod and seed counts, smaller seed size, and nutrient become a major pest of soybean [Glycine max (L.) Merr.] in North America. In the USA, there are currently no commercial soybean deficiencies resulting in overall yield and q...