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Robert Krzyżanowski

Summary

Introduction: Rose grain aphid (Metopolophium dirhodum Walk.) is one of the most important pests on cereals in Poland. The economic importance of this pest has increased in recent years due to the increase in the area of maize cultivation. M. dirhodum is an oligophagic aphid feeding also on different rose species.

Objective: The purpose of the present study was to evaluate the dynamics of population of M. dirhodum on the saltspray rose.

Methods: The studies were conducted on saltspray rose stands at Aleksandria Park in Siedlce in 2005–2009. At each selected stand, 50 rose shoots were observed every 7 days from March to spring migration of the aphid.

Results: First fundatrices of the M. dirhodum on the R. rugosa were observed at the end of March. The rose-grain aphid population development on the primary host during May, and reached maximum population in the middle of May. During autumn, the aphid backed for overwintering on the primary host.

Conclusion: While the M. dirhodum population outbreaks, the aphid might be a serious pest of the saltspray rose.

Open access

Sylwia Goławska, Robert Krzyżanowski and Iwona Łukasik

Relationship Between Aphid Infestation and Chlorophyll Content in Fabaceae Species

We determined the chlorophyll a and b levels (SPAD readings) in uninfested leaves and in leaves after 7 and 17 days of aphid infestation in four Fabaceae species (Pisum sativum L., Vicia faba L., Trifolium pretense L, Medicago sativa L.). Feeding by pea aphids Acyrthosiphon pisum Harris (Hemiptera: Aphididae) caused significant loss of chlorophyll a and b in the infested plants. Uninfested leaves on both short- and long-infestation plants had significantly higher chlorophyll a and b than infested leaves.

Open access

Hubert Sytykiewicz, Paweł Czerniewicz, Iwona Sprawka and Robert Krzyżanowski

Abstract

We measured the total chlorophyll (Chl a+b) content in seedling leaves of fifteen maize cultivars infested by two studied aphid species (oligophagous Rhopalosiphum padi L., monophagous Sitobion avenae F.) 7 and 14 days after the beginning of infestation, using a SPAD-502 chlorophyll meter. Chlorophyll loss was more severe in R. padi-infested than in S. avenae-infested plants. Chlorophyll depletion was greater after long-term (14 days) than after short-term aphid infestation in the investigated host systems. Seedlings of Złota Karłowa and Tasty Sweet were more damaged by aphid feeding; Ambrozja and Płomyk plants were less damaged by aphid feeding.