The Growth of the Coffee Berry

In Kenya the coffee berry stays in the ‘pin-head’stage for approximately 6–8 weeks after flowering. A periodof rapid growth follows which ends when the berry is about 17weeks old. Thereafter, a small loss of fresh weight seems tooccur while the dry weight remains constant for about two weeks.At this stage the beans have attained their final size but drymatter can be as low as 9 per cent. Until the time when ripeningbegins, the fresh weight of the berry increases little whilethe dry weight increases regularly. In this period dry weightis laid down mainly in the beans which attain their final dryweight when the berry is still green. During ripening of theberry (which is in fact ripening of the pulp) the fresh weightof the beans drops slightly due to loss of water. Both freshweight and dry weight of the pulp (including parchment) increaseconsiderably during ripening by approximately 121 per cent.and 106 per cent. respectively.     

Characterization of Colletotrichum kahawae Isolates Causing Coffee Berry Disease in Angola

Coffee Berry Disease, caused by Colletotrichum kahawae, is a major limitation for Arabica coffee cultivation in Africa and for which genetic control is only partially effective. As part of the effort to re‐launch coffee cultivation in Angola, our aim was to study the diversity of this pathogen and so contribute to more effective breeding for disease resistance. A collection of 30 C. kahawae isolates showed limited diversity in genetic and colony characters. However, some isolates are distinct, suggesting that breeding for disease resistance in Angola should be dependent on an adequate knowledge of the diversity of local and neighbouring C. kahawae isolates. Analysis of C. kahawae nrDNA nucleotide sequences showed distinct lineages clustering within the broad diversity of C. gloeosporioides, prompting further studies aimed at understanding the origin and pathogenic specialization of C. kahawae.     

Parasitism of the Coffee Berry Borer Hypothenemus hampei by Trichogramma pretiosum in the Laboratory

Parasitism of the coffee berry borer, Hypothenemus hampei (Ferrari) by Trichogramma pretiosum Riley resulted in high mortality of developing parasitoids and a low prevalence of adult emergence. A laboratory colony of T. pretiosum reproducing in H. hampei failed after three generations. Adult female T. pretiosum that developed in H. hampei were smaller and produced fewer eggs than conspecifics that developed in a standard lepidopteran host, Sitotroga cerealella (Olivier). Parasitoids that emerged from H. hampei preferentially parasitized S. cerealella over H. hampei. We conclude that T. pretiosum has little potential for biocontrol of the coffee berry borer.     

On the Form of the Male Reproductive Organs of Glossina (Diptera—Glossinidae)

The male reproductive organs of Glossina morsitans are described. It is shown that the common ejaculatory duct does not loop over and round the rectum as previous authors have suggested. The functional significance of the form of the common ejaculatory duct is discussed.     

Twig-Nesting Ants: The Hidden Predators of the Coffee Berry Borer in Chiapas,Mexico

Coffee is a globally important crop that is subject to numerous pest problems, many of which are partially controlled by predatory ants. Yet several studies have proposed that these ecosystem services may be reduced where agricultural systems are more intensively managed. Here we investigate the predatory ability of twig-nesting ants on the main pest of coffee, the coffee berry borer (Hypothenemus hampei) under different management systems in southwest Chiapas, Mexico. We conducted both laboratory and field experiments to examine which twig-nesting ant species, if any, can prey on free-living borers or can remove borers embedded in coffee fruits and whether the effects of the twig-nesting ant community differ with habitat type. Results indicate that several species of twig-nesting ants are effective predators of both free-living borers and those embedded in coffee fruits. In the lab, Pseudomyrmex ejectus, Pseudomyrmex simplex, and Pseudomyrmex PSW-53 effectively removed free-living and embedded borers. In the field, abundance, but not diversity, of twig-nesting ant colonies was influenced by shade management techniques, with the highest colony abundance present in the sites where shade trees were recently pruned. However, borer removal rates in the field were significant only in the shadiest site, but not in more intensively managed sites. This study provides evidence that twig-nesting ants can act as predators of the coffee berry borer and that the presence of twig-nesting ants may not be strongly linked to shade management intensity, as has been suggested for other arthropod predators of the borer.     

Polymorphic microsatellite loci in the Coffee Berry Borer,Hypothenemus hampei (Coleoptera,Scolytidae)

Microsatellite loci were isolated from the coffee berry borer, Hypothenemus hampei, which is regarded as the major pest in coffee cultures. Seven polymorphic loci were obtained from an enriched genomic library. A low to moderate genetic diversity was observed per locus, with an observed number of alleles ranging from two to five in the 39 unrelated individuals sampled from Ethiopia. A clear deficit of heterozygotes within the population (mean heterozygosities, H_O = 0.10/H_E = 0.50) and an extreme inbreeding (F_IS, 0.70–1.00) were demonstrated. Cross‐species amplifications showed that some of the markers could be useful in two closely related Hypothenemus species.     

Reaction of Some Coffea arabica Genotypes to Strains of Colletotrichum kahawae, the Cause of Coffee Berry Disease

Pathogenicity tests were performed on 11 genotypes of Coffea arabica using single‐isolate suspensions of Colletotrichum Kahawae obtained from 90 monoconidial isolates. The objective of this study was to estimate the proportion of pathogenic variation corresponding 10 differences in aggressiveness and virulence (races). A large part of the variation in the pathogen population was due to aggressiveness. The differential effects were too small to suggest conclusively that races exist. This paper discusses the possible causes for the observed small differential interaction and suggests breeding strategies that not only prevent possible adaptation of the pathogen to resistant varieties but also limit variation for resistance due to differences in aggressiveness of the pathogen.     

A Keystone Ant Species Provides Robust Biological Control of the Coffee Berry Borer Under Varying Pest Densities

Species’ functional traits are an important part of the ecological complexity that determines the provisioning of ecosystem services. In biological pest control, predator response to pest density variation is a dynamic trait that impacts the provision of this service in agroecosystems. When pest populations fluctuate, farmers relying on biocontrol services need to know how natural enemies respond to these changes. Here we test the effect of variation in coffee berry borer (CBB) density on the biocontrol efficiency of a keystone ant species (Azteca sericeasur) in a coffee agroecosystem. We performed exclosure experiments to measure the infestation rate of CBB released on coffee branches in the presence and absence of ants at four different CBB density levels. We measured infestation rate as the number of CBB bored into fruits after 24 hours, quantified biocontrol efficiency (BCE) as the proportion of infesting CBB removed by ants, and estimated functional response from ant attack rates, measured as the difference in CBB infestation between branches. Infestation rates of CBB on branches with ants were significantly lower (71%-82%) than on those without ants across all density levels. Additionally, biocontrol efficiency was generally high and did not significantly vary across pest density treatments. Furthermore, ant attack rates increased linearly with increasing CBB density, suggesting a Type I functional response. These results demonstrate that ants can provide robust biological control of CBB, despite variation in pest density, and that the response of predators to pest density variation is an important factor in the provision of biocontrol services. Considering how natural enemies respond to changes in pest densities will allow for more accurate biocontrol predictions and better-informed management of this ecosystem service in agroecosystems.     

The Distribution of Nerve Growth Factor in the Male Sex Organs of Mammals

Abstract: The Nerve Growth Factor (NGF) content of male sex organs of the mouse, rat, guinea pig, hamster, rabbit, human, and bull has been investigated using both a biological assay and a two-site radioimmunoassay. The prostate glands of the rabbit and bull have been found to contain moderate levels of NGF, these being lower than the concentrations found in the guinea pig prostate and mouse submaxillary glands. The sex organs investigated of the mouse, rat, hamster, and human contained no detectable NGF activity. Genital organs, other than the prostate glands, of the guinea pig and rabbit were also devoid of NGF. The NGFs from the rabbit and bull are immunologically related to those found in the submaxillary glands of the mouse and the prostate glands of the guinea pig, but immunodiffusion and radioimmunoassay experiments show that there are also clear differences between the NGFs. The use of a two-site radioimmunoassay, based on purified antibodies against mouse submaxillary gland NGF, for the determination of NGF levels in species other than the mouse, is described. It is essential during such applications to compensate for the fact that the NGFs from different species are sufficiently distinct that only part of the antibody population (raised against mouse NGF) is capable of recognizing NGF from species other than the mouse. The results of radioimmunoassay and biological assay determinations are in reasonable agreement, if corrections for this feature are made.     

Mating Behavior of the Coffee Berry Borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae)

The mating behavior of the coffee berry borer, Hypothenemus hampei (Ferrari), was observed under laboratory conditions. Pairs of adult virgin male and female beetles were placed in the wells of a polystyrene microtiter plate, one pair per well. The mating activity of each pair was recorded for 24?h. The mating behavior of the coffee berry borer was similar to that of other Scolytinae and was clearly divided into precopulatory, copulatory and postcopulatory phases. The beetles started to mate within a few hours of emergence. Repeated mating occurred during the 24-hour period and increased in frequency with age. However, we cannot address multiple matings in H. hampei, since we did not simulate the female-biased sex ratio of this species and the experimental design did not allow females to avoid additional mating attempts by males. In addition, further studies are necessary that focus on the effectiveness of sperm transmission and direct and indirect effects of multiple matings on the H. hampei females and their offspring.     

Strains of Colletotrichum coffeanum Noack Causing Coffee Berry Disease in Angola and Malawi with Characteristics Different to the Kenya Strain

Strains of Colletotrichum isolated from berries of Coffea arabica from Angola and Malawi were identified as C. coffeanum causing coffee berry disease (CBD). The isolates were highly aggressive to berries of the cultivar ‘Catimor’ and produced high numbers of acervuli and extremely large masses of pink conidia when cultivated in the dark. These strains are apparently different in aggressiveness and morphology to those described in the past from Kenya.     

Endocrine Organs of a Parasitic Male Deep-Sea Angler-Fish,Edriolychnus schmidti

The parasitic male deep-sea angler-fish Edriolychnus schmidti Regan 1925, which was described by Regan and Trewavas 1932, was reinvestigated with respect to the endocrine organs. Although the original microscopical sections are not in a good condition, it could be concluded that those organs which are involved in regulation of various internal environmental factors, as well as those involved in adaption to external factors, appear poorly developed or reduced. Mechanisms regulating reproductive activities seem to be well developed; a pronounced tuberis region is seen in the otherwise reduced brain and the peculiar pituitary gland appears to contain secretory active cells.     

Thermal Tolerance of the Coffee Berry Borer Hypothenemus hampei: Predictions of Climate Change Impact on a Tropical Insect Pest

Coffee is predicted to be severely affected by climate change. We determined the thermal tolerance of the coffee berry borer , Hypothenemus hampei, the most devastating pest of coffee worldwide, and make inferences on the possible effects of climate change using climatic data from Colombia, Kenya, Tanzania, and Ethiopia. For this, the effect of eight temperature regimes (15, 20, 23, 25, 27, 30, 33 and 35°C) on the bionomics of H. hampei was studied. Successful egg to adult development occurred between 20–30°C. Using linear regression and a modified Logan model, the lower and upper thresholds for development were estimated at 14.9 and 32°C, respectively. In Kenya and Colombia, the number of pest generations per year was considerably and positively correlated with the warming tolerance. Analysing 32 years of climatic data from Jimma (Ethiopia) revealed that before 1984 it was too cold for H. hampei to complete even one generation per year, but thereafter, because of rising temperatures in the area, 1–2 generations per year/coffee season could be completed. Calculated data on warming tolerance and thermal safety margins of H. hampei for the three East African locations showed considerably high variability compared to the Colombian site. The model indicates that for every 1°C rise in thermal optimum (T_opt.), the maximum intrinsic rate of increase (r _max) will increase by an average of 8.5%. The effects of climate change on the further range of H. hampei distribution and possible adaption strategies are discussed. Abstracts in Spanish and French are provided as supplementary material Abstract S1 and Abstract S2.     

Alternative Hosts for Bethylid Parasitoids of the Coffee Berry Borer, Hypothenemus hampei (Coleoptera: Scolytidae)

Three species of bethylid wasps, Prorops nasuta Waterston, Cephalonomia stephanoderis Betrem, and C. hyalinipennis Ashmead, attack the coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Scolytidae), by both predation and parasitism. C. hyalinipennis has only recently been reported to attack H. hampei. Its previously recorded hosts belong to the coleopteran families Curculionidae, Anobiidae, and Scolytidae. We evaluated five further coleopteran species, in the families Curculionidae, Bostrichidae, and Bruchidae, as alternative hosts. High proportions of all five species were both fed upon and oviposited on (normally by concurrent host feeding). Offspring developmental mortality varied greatly (12–95%) on different host species. Offspring production per host was about three times greater than on H. hampei when females were presented with the curculionids Caulophilus oryzae (Gyllenhal) and two species of Sitophilus. C. stephanoderis and P. nasuta are currently the main biological control agents of H. hampei: they have long been thought to be monophagous but C. stephanoderis has recently been reported to attack H. obscurus. We evaluated C. oryzae, as a potential host or prey for P. nasuta, and both C. oryzae and Sitophilus sp. for C. stephanoderis. Host feeding was very common in both parasitoid species. The majority of females also oviposited on C. oryzae (71% P. nasuta, 60% C. stephanoderis) and 20% of C. stephanoderis parasitized Sitophilus sp. Fifty-two percent of C. stephanoderis and 7% of P. nasuta offspring survived to adulthood when developing on C. oryzae. The lifetime fecundities of these parasitoids presented with these host species were, however, low (maximum 17 eggs, mean ≤ 8.25) and preoviposition periods were generally long (ca. 19 days). Adult female C. stephanoderis lived longer when presented C. oryzae rather than Sitophilus sp. Host feeding also increased longevity. We discuss these results in the context of mass rearing these bethylids for release as biological control agents.     

Beauveria bassiana -A Potential Mycopesticide for the Efficient Control of Coffee Berry Borer, Hypothenemus hampei (Ferrari) in India

The Coffee Berry Borer (CBB), Hypothenemus hampei (Ferrari) (Coleoptera: Scolytidae) has been a serious insect pest of coffee cultivars C. robusta and C. catimor in India since 1991, causing 40-80% coffee bean loss. To combat this important pest, an indigenous entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin was isolated from dead and moribund coffee berry borers from the wild. The fungus was cultured on yeast extractpeptone supplemented liquid medium. The mycelial mat was harvested from 12-day old cultures and lyophilized. A suspension of the most virulent isolate (Bb2) was prepared in sterile water and used as a mycopesticide. The laboratory studies were conducted on coffee berry borers by applying conidial suspensions at a dosage rate of 1 ×10 6 conidia ml -1 . Pest mortality with the Bb2 isolate increased from 69.3% to 95.3% with an increase in relative humidity (RH) at 25 ±2°C. Field experiments were conducted in a coffee plantation area in the Kodagu district of Karnataka, and the results showed that, under favourable environmental conditions (27- 29°C; 82-91% RH; 10-15 inches rainfall per year), the fungus required only eight days to colonize and kill the target pest. A maximum of 75.6% insect mortality was recorded 24 days after spraying. Large-scale field trials conducted in five plantation plots between September 1995 and September 1998 showed significant insect mortality both in C. robusta and C. catimor cultivars of coffee. The potential use of this indigenous fungal strain of B. bassiana as a mycopesticide for management of CBB in India is discussed.     

双雄性交配器官大口涡虫的首次发现

大口涡虫属所有物种均为雌雄同体,具一套交配器官。作者于2015年在广东省的两处淡水环境,首次发现2个具有双雄性交配器官的大口涡虫(Macrostomum sp.)标本。通过对活体、整装片、连续组织切片的显微镜观测,发现2只标本的两套交配器官呈左右排列;每套交配器官具备完整的假储精囊、储精囊、颗粒囊与交配刺;假储精囊与储精囊内具有精子;雄孔分别为1个与2个;交配刺的结构与中国已经记录的物种都不相同。本研究对其做了较为详细的描述,并初步探讨了大口涡虫多交配器官发生的原因。