Novel program for automatic calculation of EPG variables.

The electrical penetration graph (EPG) technique is the most powerful tool for studying the feeding behavior of pierce-sucking insects. However, calculating EPG variables is often very time-consuming, and consequently, several software programs have been developed for the automatic calculation of EPG variables. Here we present a new user-friendly Excel Workbook that uses a standardized list of EPG variables and follows expert guidelines for calculating them.

Sieve element occlusion provides resistance against Aphis gossypii in TGR-1551 melons.

Feeding behavior and plant response to feeding were studied for the aphid Aphis gossypii Glover on susceptible and resistant melons (cv. Iroquois and TGR-1551, respectively). Average phloem phase bout duration on TGR-1551 was <7% of the duration on Iroquois.

Faba bean forisomes can function in defence against generalist aphids.

Phloem sieve elements have shut-off mechanisms that prevent loss of nutrient-rich phloem sap when the phloem is damaged. Some phloem proteins such as the proteins that form forisomes in legume sieve elements are one such mechanism and in response to damage, they instantly form occlusions that stop the flow of sap. It has long been hypothesized that one function of phloem proteins is defence against phloem sap-feeding insects such as aphids.

Hitching a ride: Vector feeding and virus transmission.

The majority of plant viruses rely on insect vectors for transmission. Insects with piercing-sucking mouthparts are the most common and efficient vectors because, they are able to inject viruses into specific plant tissues. Acquisition and inoculation of viruses occurs during specific vector feeding behaviors, and feeding behavior varies greatly among insects with piercing-sucking mouthparts.

A virus capsid component mediates virion retention and transmission by its insect vector.

Numerous pathogens of humans, animals, and plants are transmitted by specific arthropod vectors. However, understanding the mechanisms governing these pathogen-vector interactions is hampered, in part, by the lack of easy-to-use analytical tools. We investigated whitefly transmission of Lettuce infectious yellows virus (LIYV) by using a unique immunofluorescent localization approach in which we fed virions or recombinant virus capsid components to whiteflies, followed by feeding them antibodies to the virions or capsid components, respectively.

Infection with a plant virus modifies vector feeding behavior.

Vector infection by some animal-infecting parasites results in altered feeding that enhances transmission. Modification of vector behavior is of broad adaptive significance, as parasite fitness relies on passage to a new host, and vector feeding is nearly always essential for transmission. Although several plant viruses infect their insect vectors, we have shown that vector infection by a plant virus alters feeding behavior.