626 Invasive Stink Bugs and Related Species (Pentatomoidea)
as vectors, including Lygaeidae, Rhyparochromidae, Stenocephalidae, and Pentatomidae (Camargo and
Wallace 1994). Edessa loxdalii Westwood was able to transmit Phytomonas sp. to seedlings of Cecropia
palmata Willd. in Suriname and 51% of the wild population harbored these organisms in the salivary
glands (Kastelein 1985; cited in Camargo and Wallace 1994). Only one instance of pathogenicity of a latex-
inhabiting species has been reported, in cassava (Vainstein and Roitman 1986). However, the insect vector
was never determined and the cassava cultivar susceptible to infection is no longer grown (Camargo 1999).
Fruit-inhabiting forms, isolated from tomato, corn, and other crops, are vectored by a number of het-
eropterans, including coreids (Jankevicius et al. 1989) and the pentatomids Nezara viridula (Gibbs 1957)
and Arvelius albopunctatus (De Geer) (Kastelein and Camargo 1990). In both pentatomid species, the
flagellates are found in the digestive tract and the salivary glands. This group of trypanosomatids is not
of serious economic concern. Infection is suspected to cause fruit spotting (Camargo 1999), but infected
fruits may be unblemished and there is no clear evidence of pathogenicity.
Phloem-limited trypanosomatids are by far the most economically damaging, contributing to substan-
tial losses in coconut, oil palm, and coffee production in South America. The vector of coffee necrosis,
caused by Phytomonas leptovasorum Stahel, has not been determined. Ochlerus spp. (Pentatomidae:
Discocephalinae: Ochlerini) harbor the trypanosome, but transmission has not been demonstrated exper-
imentally (Vermeulen 1968; cited in Camargo 1999). Suspicion also has fallen on two species of the
pentatomid genus Lincus Stål, namely L. spathuliger Breddin (Stahel 1954; cited in Dollet 1984), and
L. styliger Breddin (Dollet 1984), but, again, no transmission could be shown.
Two serious diseases of palms transmitted by phloem-limited trypanosomatids, hartrot of coconut
and “marchitez sorpresiva” (sudden wilt) of oil palm, are caused by Phytomonas staheli McGhee and
McGhee and were shown to be transmitted by pentatomids in the genus Lincus (Camargo and Wallace
1994). The palm diseases caused by trypanosomatids are restricted to Central and South America and
the Caribbean. Several species of palms other than the major economic species also are affected by
Phytomonas staheli, including açaí (Camargo et al. 1990 and references therein, Meneguetti and Trevisan
2010). A wilt of ornamental red ginger [Alpinia purpurata (Vieillard) K. Schumann] in the Caribbean is
caused by a similar strain of this trypanosomatid (Dollet et al. 2001).
13.6.2 Coconut
Hartrot of coconut, Cocos nucifera L., is a lethal wilt that has been reported from Brazil, Columbia,
Ecuador, Suriname, Trinidad, Costa Rica, and French Guiana (Dollet 1984, McCoy et al. 1984, Resende
et al. 1986). Leaves wilt and turn brown, starting from the lowest leaves and advancing upwards. Floral
buds become necrotic, unripe fruit drops, the apical shoot rots, and eventually the entire heart of palm
is destroyed, including the roots. From visible symptoms to death takes 10 weeks to several months
and because the spread is rapid, entire plantations may be demolished by this disease (Bezerra and
Figueiredo 1982, Dollet 1984, Camargo 1999).
Hartrot first was noted in Suriname over 100 years ago, but the etiological agent remained unknown
until 1976, and the relationship between the trypanosomatid and its insect vectors was not established
until the 1980s (Camargo 1999). Early studies linked the disease to the genus Lincus, but, often, the
transmission studies used a mix of species, or identification was taken only to genus. Taxonomic work
by Dolling (1984) and Rolston (1983, 1989) has helped to clarify the vectors. Hartrot, most likely, is
transmitted in French Guiana by L. bipunctatus (Spinola) (Louise et al. 1986, as L. croupius Rolston);
this species can acquire trypanosomatids in the laboratory from diseased coconut, which then can be
recovered from the salivary glands (Dollet et al. 2002). Cage studies documented transmission of har-
trot from wild-collected bugs to healthy coconut palms, but two other species, L. dentiger Breddin and
L. apollo Dolling, also were included initially in these experiments (Louise et al. 1986). In Suriname,
L. vandoesburgi Rolston and L. lamelliger Breddin occur on diseased coconut, and one or both species
are responsible for disease transmission (Asgarali and Ramkalup 1985; cited in Camargo and Wallace
1994). In Brazil, L. lobuliger Breddin is the vector (Resende et al. 1986).
A simulation model incorporating the plant, the trypanosomatid Phytomonas staheli, and the vector
Lincus lobuliger was developed for coconut in Brazil. These bugs gather on the undersides of leaf petioles,
feeding from the phloem sap of stipules. At night, adults and nymphs may be found moving about on the