Effect of Tithonia diversifolia Mulch on Atta cephalotes (Hymenoptera: Formicidae) Nests

Abstract

Recent studies have shown an insecticidal effect of Tithonia diversifolia (Hemsl.) Gray (Asterales: Asteraceae) foliage on workers of Atta cephalotes L. and inhibitory effects of this plant on the growth of the symbiotic fungus Leucoagaricus gongylophorus (A. Müler) Singer. To evaluate the potential of T. diversifolia as a biological control treatment of this important pest, we assessed the effect of green manure (mulch) of this plant on natural nests of A. cephalotes, in Cali, Colombia. Three treatments were randomly assigned to 30 nests: 1) green mulch of T. diversifolia, 2) green mulch of Miconia sp., Ruiz & Pav. and 3) unmulched control. Every 2 wk for 6 mo, the surface of the nests was completely covered with leaves. Physical and chemical parameters of nest soil were assessed before the first and after the last application of the mulch. Ant foraging in T. diversifolia-treated nests decreased by 60% after the initial applications of the mulch, while nest surface area decreased by 40%. When the nests covered with T. diversifolia were opened, it was observed that the superficial fungus chambers had been relocated at a greater depth. In addition, microbial activity and soil pH increased by 84% and 12%, respectively, in nests covered with plant residues. In conclusion, the continued use of T. diversifolia mulch reduces foraging activity and negatively affects the internal conditions of the colonies, thereby inducing the ants to relocate the fungus chambers within the nests.

Aktivitas Insektisida Ekstrak Tithonia Diversifolia (Hemsl.) a Gray (Asteraceae) Terhadap Ulat Daun Kubis Plutella Xylostella (L.) (Lepidoptera: Yponomeutidae)

“…(Osipitan & Oseyemi, 2012). Tithonia diversifolia juga dapat dimanfaatkan untuk mengendalikan Sitophilus zeamais (Onekutu et al, 2015) dan Atta cephalotes (Hymenoptera: Formicidae) (Zanetti et al, 2014, Rodriguez et al, 2015. Tithonia diversifolia diketahui mengandung beberapa senyawa metabolit sekunder diantaranya seskuiterpena, diterpena, monoterpena, dan kandungan alisiklik yang bersifat toksik yang berasal dari bagian daun, batang, atau bunga .…”

Insecticidal and Cholinesterase Activity of Dichloromethane Extracts of Tithonia diversifolia on Atta cephalotes Worker Ants (Formicidae: Myrmicinae)

“…Furthermore, ethanol extract from T. diversifolia dry leaves will produce 100% worker ant mortality in only eight days [10]. Recently, in a study conducted under natural conditions, Rodriguez et al [11] observed that green manure made with T. diversifolia will induce the displacement of the fungus-rearing chambers to deeper zones as well as the construction of new chambers outside the areas of manure degradation. Thus, due to its antifungal and insecticidal properties, the sunflower shows great potential for the control of leaf-cutter ants as well as other agricultural pests.…”

CONSTITUINTES QUÍMICOS E ATIVIDADE INSETICIDA DE Miconia ferruginata

“…sobre o fungo Leocoagaricus gongylophorus. 16 Extratos de M. affinis foram testados sobre os fungos fitopatogênicos (Botryotinia fuckeliana, Magnaporthe oryzae, Phytophtora infestans e Septoria tritici). 17 A cultura do milho é de suma importância para a economia do Brasil, sendo este o terceiro maior produtor mundial.…”