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Field host-range surveys and fixed plot trials were undertaken in Jamaica to gain an understanding of the host range of the fly Melanagromyza eupatoriella (Diptera: Agromyzidae), a potential biological control agent of the neotropical shrub Chromolaena odorata in South Africa. The fly larvae form helical mines in growing, vegetative stem tips, causing them to wilt and die. Seventy-seven sites at which C. odorata was present along with 30 other species of Asteraceae were surveyed for the presence of damage similar to that caused by M. eupatoriella. Twelve of these sites, chosen for the high (>10) number of M. eupatoriella mines present on C. odorata, were used to determine the abundance of 19 Asteraceae species encountered and the proportion of shoot tips with helical mines on each of these species. Similar mines were found on six species other than C. odorata: Mikania micrantha, M. cordifolia, Bidens alba, B. pilosa, B. reptans and Calea jamaicensis. Damaged plant material was field-collected from M. micrantha, C. odorata and B. alba and the causative herbivores (all Agromyzidae) were preserved for identification. Mines on Mikania species were longer than those caused by M. eupatoriella, and the species collected from M. micrantha was tentatively identified as Melanagromyza vulgata. Helical shoot-tip mines on Bidens species continued internally to completion further down the stem, unlike those of M. eupatoriella, where pupation occurs near the base of the helical mine. Only adult females were reared out of B. alba, therefore the fly could only be identified as a Melanagromyza species. The proportion of shoot tips with helical mines was highest on the two Mikania species, intermediate on C. odorata, and lowest on B. alba. For the quantitative, 12-site survey, five plant species in addition to C. odorata were present at four or more sites, and were significantly less likely than C. odorata to host M. eupatoriella. A fixed-plot trial was undertaken using two forms of C. odorata (plants from Jamaica and the southern African biotype), six Asteraceae (all encountered in the host-range sur-veys) and two crop species. Over 19 months, both C. odorata forms were attacked by M. eupatoriella and one mine was encountered on B. alba. The surveys, trials and identification of insects indicate that shoot-tip mines caused by M. eupatoriella were encountered only on C. odorata, out of 31 Asteraceae and two other plant species. Further laboratory-based host-range trials are required, should there be a need for this insect as a biocontrol agent in future.

Cacao is an economically important commodity in Jamaica. Knowledge of the genetic diversity of Jamaican cacao germplasm is essential for their conservation and management. In spite of cacao’s economic importance in Jamaica, the crop is under studied, therefore limiting sound decisions toward improving productivity. Assessment of germplasm and on-farm genetic diversity is required to assist selecting superior genotypes to propagate and distribute across the island, as well as to use them as parental clones in breeding programs. Using 94 single nucleotide polymorphism (SNP) markers, 140 Jamaican cacao samples from two germplasm collections and a farmer’s estate along with 150 reference samples were analyzed. The principal coordinate analysis demonstrated that the majority of the Jamaican cacao selections were hybrids derived from five original germplasm groups, including Criollo, Amelonado and three Upper Amazon Forastero groups. Among the Upper Amazon groups, the Bayesian clustering analysis revealed that the Parinari (PA) ancestral lineage contributed the most (29.9%) to the Jamaican cacao germplasm. The germplasm collections showed greater diversity in terms of ancestral contributions compared to the farmer’s estate. However, the genetic differentiation between the three collecting sites was small (Fst = 0.036), indicating that samples collected from the three sites were derived from a common pool of germplasm. The current study supports the historical records and clarified the ancestry of Jamaican cacao. Although the majority of the cacao genetic groups were observed in the Jamaican cacao collections, several diversity gaps were found in both germplasm collections and in the farmer’s estate, especially germplasm with disease resistance to cacao frosty pod rot that was recently found in Jamaica.

Introduction Neglected tropical diseases (NTDs) in developing countries like the Caribbean, negatively affect multiple income-generating sectors, including the tourism industry upon which island states are highly dependent. Insect-transmitted NTDs include, but are not limited to, malaria, dengue and lymphatic filariasis. Control measures for these disease, are often ignored because of the associated cost. Many of the developing country members are thus retained in a financially crippling cycle, balancing the cost of prophylactic measures with that of controlling an outbreak. The purpose of the paper is to bring awareness to NTDs transmitted by insects of importance to humans, and to assess factors affecting such control, in the English-speaking Caribbean. Method Comprehensive literature review on reports pertaining to NTDs transmitted by insects in the Caribbean and Latin America was conducted. Data search was carried out on PubMed, and WHO and PAHO websites. Results and conclusion Potential risk factors for NTDs transmitted by arthropods in the English-speaking Caribbean are summarised. The mosquito appears to be the main insect-vector of human importance within the region of concern. Arthropod-vectors of diseases of veterinary importance are also relevant because they affect the livelihood of farmers, in highly agriculture based economies. Other NTDs may also be in circulation gauged by the presence of antibodies in Caribbean individuals. However, routine diagnostic tests for specific diseases are expensive and tests may not be conducted when diseases are not prevalent in the population. It appears that only a few English-speaking Caribbean countries have examined secondary reservoirs of pathogens or assessed the effectivity of their insect control methods. As such, disease risk assessment appears incomplete. Although continuous control is financially demanding, an integrated and multisectoral approach might help to deflect the cost. Such interventions are now being promoted by health agencies within the region and various countries are creating and exploring the use of novel tools to be incorporated in their insect-vector control programmes., Highlights • Neglected tropical disease transmitted (NTDs) by insects in English-speaking Caribbean • Past and current challenges associated with the control of NTDs transmitted by insects in the English-speaking Caribbean. • Potential risks factors of arthropod-borne diseases in the English-speaking Caribbean. • Highlights on research areas that could strengthen elimination strategies of insect transmitted NTDs in the Caribbean.

The frequent use of endosulfan in agricultural activity on steep slopes in Jamaica and subsequent contamination of rivers by the residues resulted in a need to assess the levels of bioaccumulation of sub-lethal doses of the insecticide in river fauna using Tilapia fish as a test subject. Bioconcentration of I±- and I²-endosulfan by the Red Hybrid Tilapia, from 0.0075 mg L-1 in the surrounding water, reached a peak (0.578 ppb and 0.442 ppb, respectively) in one to four hours but fluctuated during the rest of the 72-h observation period. A similar pattern of bioaccumulation was recorded when the fish were exposed to 0.015 mg L-1, except that the peak bioaccumulation of I±- and I²-isomers after one hour of exposure were 0.54 and 0.44 mg L-1, respectively. The contaminated fish (from 24-h exposure to 0.015 mg L-1) eliminated only 18 to 31% of endosulfan residues after 24 h and 26 to 39% after 72-h exposure to uncontaminated water. During the process of bioconcentration, endosulfan was metabolized to endosulfan lactone and sulfate; the degradation was more during the elimination process when exposed to clean water. Maximum amounts of I±-and I²-endosulfan and their metabolites were partitioned in gonads > liver > gills > skin/muscle/bone.

Exposure of mature red hybrid Tilapia sp. to a range of sub-lethal concentrations of endosulfan for 21 days induced a spectrum of often not clearly distinguishable Behavioural Toxic Symptoms (BTS), ranging from reversible to eventually fatal responses. The No Observed Effect Concentration (NOEC: Below the threshold of BTS) and the Lowest Observed Effect Concentration (LOEC: Above the threshold of low intensity and reversible BTS and below the threshold of any mortality) were 25% to 50% of the fish) were 0.01 and 0.02 mg L?1, respectively. The 3-day and 21-day LC50 values were 0.031 and 0.016 mg L?1, respectively.

The toxic effects of the alkaloids, Norharman and a mixture of L-N-Methylcrotonosine/Linearisine (M/L mixture), on two organisms, Gambusia puncticulata and Veronicella sloanei were determined. The effect of the alkaloids on the fecundity of Thiara granifera was also investigated. Norharman was harmless to G. puncticulata but the M/L mixture inflicted 55.5% mortality on fish populations. The alkaloids had narcotizing, repellent and anti-feedant effects on V. sloanei. The M/L mixture suppressed the development of hatchlings in the brood pouches of T. granifera. Norharman and the M/L mixture reduced the number of hatchlings released from the brood pouches of T. granifera by 60 and 40%, respectively.

Multiple sizes of Sea bream were collected from Kingston Harbour, Jamaica, to assess steady state bioaccumulation of polychlorinated biphenyls (PCBs) in a tropical fish. Sea beam fork lengths ranged from 7.3 to 21.5 cm (n = 36 fish) and tissue lipids decreased with body length. Larger fish had lower δ13C isotopes compared to smaller fish, suggesting a change in diet. Linear regressions showed no differences in lipid equivalent sum PCB concentrations with size. However, differences in individual congener bioaccumulation trajectories occurred. Less hydrophobic PCBs decreased with increasing body length, intermediate PCBs showed no trend, whereas highly hydrophobic (above log KOW of 6.5) PCBs increased. The different congener patterns were interpreted to be a result of decreases in overall diet PCB concentrations with increased fish length coupled with differences in PCB toxicokinetics as a function of hydrophobicity yielding dilution, pseudo-steady state and non-steady state bioaccumulation patterns.