Aphid populations (Hemiptera: Aphidoidea) depend of mulching in watermelon production in the Mediterranean region of Croatia

Abstract

Winged morphs of aphids were investigated under field conditions during 2008, 2010 and 2011 in the Mediterranean region of Croatia. Field experiments were conducted to record aphid diversity and compare polyethylene black mulch to straw mulch and bare soil in terms of their attractiveness to aphid species in a watermelon crop. Aphids were collected weekly using yellow water metal traps from May to July. During the study, 44 species in 31 genera were detected; 36 species in 24 genera were identified in 2008, 18 species in 15 genera were identified in 2010, and 34 species in 25 genera were identified in 2011. The overall seasonal percentage composition showed that Aphis fabae Scopoli and Myzus persicae (Sulzer) were consistently eudominant species, whereas Acyrtosiphon pisum (Harris) was consistently dominant. Cabbage aphid Brevicoryne brassicae (L.) was determined as the dominant species in 2008 and as eudominant species in 2011. Additionally, Macrosiphum rosae (L.) was twice recorded as the dominant species, whereas Aphis gossipii Glover was dominant once, and Phorodon humuli (Schrank) was eudominant once. Our study also demonstrated that mulching sporadically affected the abundance of individual species. The attractiveness of mulching for aphid species differed between the treatments. It was found that bare soil was attractive to A. pisum and M. rosae, black mulch was attractive to B. helichrysi and P. humuli, and straw mulch was attractive to four aphid species, of which two were eudominant, A. fabae and M. persicae. The presented species are mostly polyphagous, and their preference for certain mulches can be used in crop protection management.