Callose deposition is induced in plants by various stress factors such as when plants are attacked by herbivores and pathogens. Golden Promise. These two genes were previously found to be upregulated by the cereal pest Rhopalosiphum padi L.
All mutant lines had single base insertions, causing frame shifts and premature stop codons. However, we found no effect of these modified plant traits on barley resistance to R. Both genes were confirmed to be upregulated by R. Aphids are phloem-feeding insects. Out of approximately 4, species in the Aphididae family, ca are crop pests Blackman and Eastop, They damage plants directly when feeding on phloem sap, but also indirectly by vectoring viral diseases.
The most common aphid control method in field crops is to apply insecticides. To grow aphid-resistant cultivars is a control method that is more environmentally friendly, less risky for human health, less costly, and more easily applied. However, relatively few cultivars have been bred for resistance to their aphid pests so far. Among the examples are wheat and barley cultivars with resistance to one or both of Schizaphis graminis Rondani and Diuraphis noxia Kurdjumov Mornhinweg et al.
Plant resistance traits may confer both physiological antibiosis and behavioral antixenosis effects on the insect Smith, Causes for insect resistance are thus more complicated to study than causes for disease resistance.
However, compared to chewing herbivorous insects, aphids make only small mechanical damage to their hosts and aphids are relatively sedentary once they have accepted a plant to feed and reproduce on. Two of three aphid-resistance genes that have been sequenced so far, Mi-1 in tomato and Vat in melon, belong to the nucleotide-binding-site leucine-rich repeat NBS-LRR family of R genes Rossi et al.
