Slow wilt: another form of Marchitez in oil palm associated with trypanosomatids in Peru

Abstract

Another form of Marchitez manifestation affecting oil palm (Elaeis guineensis) has been observed since 2002 in the Alto Huallaga area from Peru. Externally, the disease appears as chlorosis, drying and breaking of the lower leaves, rot in fruit bunches, accumulation and rot of spears. Internally, the meristem presents brown lesions with a yellowish halo around its base. A high proportion (94%) of affected plants showed trypanosomatids in their roots. After follow up asymptomatic plants for 22 months, 85% develop symptoms of slow wilt. After the appearing of the symptoms the affected plants die between 5 and 8 months. Lincus spurcus population present in affected plants was evaluated and 44% were positive for trypanosomatids. In addition, trypanosomatids were observed in wild plants such as Acalypha cuneata, Urera caracasana, Trema micrantha, Cecropia spp., present in areas with incidence of the disease. The chlorosis, the long period of incubation and the time evolution of the disease are different in comparison with sudden wilt, suggesting a new disease manifestation affecting oil palms. The presence of Lincus positive to trypanosomatids leads us to propose an association of these parasites with slow wilt as reported for sudden wilt.

New records and update on the geographic distribution of fifteen species of Lincus Stål, 1867 (Insecta: Hemiptera: Pentatomidae) associated with palms and coconut trees in the Neotropics

“…Distribution data (Table 2) are from Rolston (1983), Llosa et al (1989) andDi Lucca et al (2013). Breddin, 1908 Figures 1N, 2, 4J; Tables 1, 2 Body castaneous, measuring between 11.50-12.50 mm, with 1 + 1 yellow spots on apex of radial veins.…”

“…The causal agent of hartrot and Marchitez is a protozoan of the family Trypanosomatidae, Phytomonas staheli McGhee & McGhee, 1979. This pathogen can be transmitted by pentatomids of the tribe Ochlerini as Macropygium Spinola, 1837, Ochlerus Spinola, 1837, and mainly Lincus Stål, 1867 (Couturier & Kahn 1989, 1992Camargo 1999;Howard 2001;Mitchell 2004;Di Lucca et al 2013).…”

“…Lincus is distributed exclusively in the Neotropical region, already recorded in Bolivia, Brazil, Colombia, Ecuador, French Guiana, Panama, Peru, Surinam, and Venezuela. The majority of described species are from Peru (Rolston 1983(Rolston , 1989Dolling 1984;Couturier & Kahn 1989, 1992Llosa et al 1990;Dollet et al 1993;Di Lucca et al 2013;Maciel et al 2015;Campos & Roell 2017). Lincus was revised in the late 20 th century by Rolston (1983) who provided the description of the majority of currently known species and a key to their identification.…”

“…hebes, L. malevolus and L. spurcus, and Campos & Roell (2017) described L. curvatus collected in palms in Ecuador. Currently, Lincus comprises 36 described species (Rolston 1983a(Rolston , 1989bDolling 1984;Campos & Grazia 2006;Grazia et al 2015;Campos & Roell 2017), and 15 of them have already been reported on palms and coconut trees (Stahel 1954;Desmier de Chenon 1984;Dolling 1984;Louise et al 1986;Resende 1986;Rolston 1989;Camargo 1999;Alves de Souza 2000;Panizzi et al 2000;Mitchel 2004;Di Lucca et al 2013;Maciel et al 2015;Campos & Roell 2017).…”

Description of the males of Lincus singularis and Lincus incisus (Hemiptera: Pentatomidae: Discocephalinae)

“…Spanish-speaking countries) diseases in palm trees (Arecaceae) in South America, being of economic interest in crops of E. guineensis (African oil palm) and Cocos nucifera L. (coconut) (DESMIER DE CHENON 1984, COUTURIER & KAHN 1989, PERTHUIS et al 1985, PANIZZI et al 2000, DI LUCCA et al 2013; for a review see HOWARD 2001). Although eleven species of Lincus have been reported on palm trees (HOWARD 2001), the genus was not listed as a possible vector of oil palm diseases until the 1980's (COUTURIER & KAHN 1992).…”