Premium
Analysis of wheat resistance to the cereal aphid Sitobion avenae using electrical penetration graphs and flow charts combined with correspondence analysis
Author(s) -
Caillaud Claudia M.,
Pierre J. S.,
Chaubet B.,
Pietro J. P.
Publication year - 1995
Publication title -
entomologia experimentalis et applicata
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.765
H-Index - 83
eISSN - 1570-7458
pISSN - 0013-8703
DOI - 10.1111/j.1570-7458.1995.tb01904.x
Subject(s) - sitobion avenae , phloem , biology , aphid , homoptera , xylem , botany , pest analysis , horticulture , poaceae , aphididae , agronomy
The behaviour of Sitobion avenae (F.) was compared on resistant wheat lines of Triticum monococcum (L.) and a susceptible variety of Triticum aestivum (L.). Firstly, stylet penetration activities were monitored with the Electrical Penetration Graph (EPG) technique and subsequently analysed using flow charts combined with correspondence analysis. Plant resistance was shown to be associated with repeated penetrations without access to either the xylem or the phloem, and with numerous failures in starting a sustained sap ingestion (as represented by pattern E2). Access to sieve elements of the phloem did not seem to be much affected on resistant plants but it took the aphid three times as long to produce a sap ingestion pattern when maintained on the resistant line T. monococcum n ° 44 (Tm44) as compared with aphids maintained on susceptible plants. As a result the total time spent in ingesting from sieve elements was reduced by 72% on Tm44. Secondly, direct observations of freely‐moving apterous adults were performed. Aphids did not discriminate between resistant and susceptible wheat during the first 30 min of access to test leaves, but only 4 out of 25 aphids were still probing after eight hours on resistant Tm44. The relevance of these results to possible location of the resistance factor(s) are discussed. Although detection of plant resistance before sieve elements are reached can not be rigorously excluded, the factors involved in T. monococcum resistance to S. avenae undoubtedly occur within the phloem vessels.