Effect of Microclimate on the Mass Emergence of Hypothenemus hampei in Coffee Grown under Shade of Trees and in Full Sun Exposure

The rainfall regime has a significant impact on the microclimate and mass emergence of the coffee berry borer, Hypothenemus hampei (Coleoptera: Curculionidae) (CBB). Little is known, however, about the shade tree-microclimate-CBB mass emergence interaction. The objective of the present study was to compare the effect of microclimate on the mass emergence of CBB in a full sun-exposed plot with a plot shaded by trees. The experiment was conducted on a Robusta coffee farm in southern Chiapas, Mexico. In each plot, 18 traps baited with an alcohol mixture were installed to capture flying females, collecting caught individuals every hour from 8:00 to 18:00 h. A meteorological station recorded several microclimatic variables on 13 weekly sampling dates from February to May 2022. Significantly more CBB females were captured in the shaded plot. The largest number of CBB captures was recorded between 14:00 and 16:00 h for the shade plot and between 15:00 and 17:00 h for the sun-exposed plot. The mass emergence of CBB showed a positive association with precipitation, dew point, and wind speed samples and a negative association with maximum air temperature, average relative humidity, ultraviolet radiation, wind speed, and equilibrium moisture content. Our observations show that the relationship between shade trees, microclimate, and mass emergence of CBB is complex and that its study helps us to gain deeper insight into CBB bioecology and advance control techniques against this important pest.

Transformation of coffee-growing landscapes across Latin America. A review

In Latin America, the cultivation of Arabica coffee (Coffea arabica) plays a critical role in rural livelihoods, biodiversity conservation, and sustainable development. Over the last 20 years, coffee farms and landscapes across the region have undergone rapid and profound biophysical changes in response to low coffee prices, changing climatic conditions, severe plant pathogen outbreaks, and other drivers. Although these biophysical transformations are pervasive and affect millions of rural livelihoods, there is limited information on the types, location, and extent of landscape changes and their socioeconomic and ecological consequences. Here we review the state of knowledge on the ongoing biophysical changes in coffee-growing regions, explore the potential socioeconomic and ecological impacts of these changes, and highlight key research gaps. We identify seven major land-use trends which are affecting the sustainability of coffee-growing regions across Latin America in different ways. These trends include (1) the widespread shift to disease-resistant cultivars, (2) the conventional intensification of coffee management with greater planting densities, greater use of agrochemicals and less shade, (3) the conversion of coffee to other agricultural land uses, (4) the introduction of Robusta coffee (Coffea canephora) into areas not previously cultivated with coffee, (5) the expansion of coffee into forested areas, (6) the urbanization of coffee landscapes, and (7) the increase in the area of coffee produced under voluntary sustainability standards. Our review highlights the incomplete and scattered information on the drivers, patterns, and outcomes of biophysical changes in coffee landscapes, and lays out a detailed research agenda to address these research gaps and elucidate the effects of different landscape trajectories on rural livelihoods, biodiversity conservation, and other aspects of sustainable development. A better understanding of the drivers, patterns, and consequences of changes in coffee landscapes is vital for informing the design of policies, programs, and incentives for sustainable coffee production.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13593-021-00712-0.

The singular insemination status of Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae) females during the inter-harvest season of a coffee crop

The coffee berry borer, Hypothenemus hampei (Ferrari), can survive in residual coffee berries during the inter-harvest period, while new fructification only appears 2-3 months after the last harvest. The dispersal of colonizing females is an adaptation that enables the life cycle of the species to go ahead whenever his flight aptitude allows. This paper focuses on accurately determining the rate of inseminated females ready to reproduce when emerging from residuals berries to colonize new ones, which constitutes a characteristic of the live cycle far from common in Curculionidae. We dissected females caught in traps baited with a mixture of alcohols during the inter-harvest season, females from infested residual berries collected from branches, and virgin females obtained from pupae reared individually in the laboratory. After microscopic preparation with Giemsa stain, spermathecae were observed to identify the physiological status of each specimen. Out of the females found in the traps, 98.4% displayed recent and abundant insemination and 1.6% sporadic insemination. In contrast, in residual berries, most of females were recently inseminated (84.5%), followed by virgin females (10.5%) and older inseminated females (5%). In addition, the flight tests of the virgin females were negative. These results indicate that all colonizing females were inseminated, ready for flying and oviposition, females inside residual berries showed different physiological status, and virgin females could not migrate since they could not flight. The large number of inseminated females inside the residual berries, and the capacity of migrating females to colonize and reproduce, suggest that it is necessary to control residual berries and use traps to stop the dispersal and reproduction of this pest.

Short-distance dispersal of Hypothenemus hampei (Ferrari) females (Coleoptera: Curculionidae: Scolytidae) during the coffee tree fruiting period

The coffee berry borer (CBB), Hypothenemus hampei (Ferrari), is a multivoltine species closely associated with coffee crops worldwide, causing severe damage to the bean. In Mexico, as in all tropical regions, CBB survives during the inter-harvest period in residual berries on the ground or in dry berries remaining on the branches, and then disperses in search of the first suitable berries. In this study, we investigated how CBB dispersed from the first infested nodes during the fruiting period of Coffea canephora Pierre, which provides a favourable trophic level for this insect. Forty-five branches equally distributed in 15 coffee trees, with one infested node and four uninfested nodes, were selected. The branches were subjected to three treatments over nine weeks: 1) glue between nodes with full protection, 2) glue between nodes without protection, and 3) no glue and no protection. In addition, 45 CBB-free branches were selected and subjected to the same three treatments. CBB colonization can occur in three ways: 1) from an infested node to an uninfested node on the same branch, 2) from infested berries to uninfested berries within the nodes, 3) from branches to other branches. We also found that CBB dispersal between nodes of the same branches never occurred by walking but by flying. Thus, in this context of coffee berry development and ripening, and unlike the phenological situation of the inter-harvest period, CBB continuously travels very short distances, thus limiting its control.

First instar larvae morphology of Opiinae (Hymenoptera: Braconidae) parasitoids of Anastrepha (Diptera: Tephritidae) fruit flies. Implications for interspecific competition

The morphology of the first instars of the Opiinae braconids Diachasmimorpha longicaudata, Doryctobracon areolatus, Doryctobracon crawfordi, Utetes anastrephae and Opius hirtus (the first is exotic, and the others are natives to Mexico), parasitoids of Anastrepha fruit flies, are described and compared. The possible implications on interspecific competition among these species are discussed. The most significant adaptations found were: (1) the mouth apparatus, where the large mandibles and fang-shaped maxillary lobes present in D. longicaudata and U. anastrephae larvae were absent in O. hirtus, D. areolatus and D. crawfordi larvae, and (2) the degree of mobility for exploration and escape, such as the lateral and caudal appendages that were only present in D. longicaudata (ventrolateral appendages in the base of the head capsule), U. anastrephae (caudal lobe with two appendages) and D. areolatus (caudal lobe with a round apex with a globular shape). The first instar larvae of the species D. longicaudata show morphological adaptations that apparently confer competitive advantages against the larvae of D. areolatus, D. crawfordi and O. hirtus. However, the first instar larvae of U. anastrephae show larger mandibles, an adaptation that could enable this species to resist competition from D. longicaudata.

Horizontal transmission of Beauveria bassiana in Anastrepha ludens (Diptera: Tephritidae) under laboratory and field cage conditions

The virulence of two products of the fungus Beauveria bassiana (LCPP and Bassianil) on adult Anastrepha ludens (Loew) (Diptera: Tephritidae) and their effect on the mating performance of infected males was evaluated in laboratory and field cage tests. The horizontal transmission capacity of the fungus during copulation or attempted copulation also was quantified using inoculated males as well as the impact of infection on female fecundity and longevity. Both fungal products were found to be highly virulent (LCPP, mortality = 98.7% at 1 x 10(8) conidia per ml, LT50 = 4.20 d, LC50 = 9.35 x 10(5) conidia per ml; Bassianil, mortality = 99.3% at 1 X 10(8) conidia per ml, LT50 = 4.04 d, LC50 = 2.69 x 10(7) conidia per ml). Mating success of inoculated males was not affected compared with the control group during the 3 d postinoculation. Horizontal transmission to females during the first day was 80.6 and 84.3% through mating and 15.4 and 21.6% through attempts to mate and contact during courtship for the LCPP and Bassianil products, respectively. The fertility of infected females was notably reduced, and longevity did not extend beyond 15 d. Our results suggest the possibility of using sterile flies as fungus vectors in sterile insect technique programs, but the potential benefits and shortcomings of this approach require further investigation.

Horizontal transmission of Beauveria bassiana in Anastrepha ludens (Diptera: Tephritidae) under laboratory and field cage conditions

The virulence of two products of the fungus Beauveria bassiana (LCPP and Bassianil) on adult Anastrepha ludens (Loew) (Diptera: Tephritidae) and their effect on the mating performance of infected males was evaluated in laboratory and field cage tests. The horizontal transmission capacity of the fungus during copulation or attempted copulation also was quantified using inoculated males as well as the impact of infection on female fecundity and longevity. Both fungal products were found to be highly virulent (LCPP, mortality = 98.7% at 1 x 10(8) conidia per ml, LT50 = 4.20 d, LC50 = 9.35 x 10(5) conidia per ml; Bassianil, mortality = 99.3% at 1 X 10(8) conidia per ml, LT50 = 4.04 d, LC50 = 2.69 x 10(7) conidia per ml). Mating success of inoculated males was not affected compared with the control group during the 3 d postinoculation. Horizontal transmission to females during the first day was 80.6 and 84.3% through mating and 15.4 and 21.6% through attempts to mate and contact during courtship for the LCPP and Bassianil products, respectively. The fertility of infected females was notably reduced, and longevity did not extend beyond 15 d. Our results suggest the possibility of using sterile flies as fungus vectors in sterile insect technique programs, but the potential benefits and shortcomings of this approach require further investigation.

Design and evaluation of traps for Idiarthron subquadratum (Orthoptera: Tettigoniidae) with farmer participation in coffee plantations in Chiapas, Mexico

Three new types of traps designed and made by farmers were evaluated for capture of Idiarthron subquadratum Saussure & Pictet. Bag, sack, and fabric traps were compared with previously used bamboo internode traps. A participatory methodology was used involving farmer interviews and workshops to design and make the traps. Farmer participation was useful for obtaining information on perceptions, knowledge, and control activities of I. subquadratum. The bag trap captured a greater number of individuals than the bamboo and fabric traps, but its captures were similar to those of sack trap; captures were similar in bamboo, sack, and fabric traps. When captured individuals were analyzed by stage of development, no significant differences between types of traps were detected for captured adults. The number of individuals captured in the traps showed a similar trend to that counted in nocturnal sampling. A significant positive relationship was detected between numbers of adults captured and the damage of leaves and fruits. Taylor's Power Law indicates that I. subquadratum individuals were more abundant in some traps than in others. With densities greater than five individuals per trap, a smaller number of bag traps was required to estimate the same population compared with the other types of traps. Sampling procedure that used the bag traps had the lowest cost. This study shows that resource-poor coffee, Coffea arabica L., farmers had accumulated knowledge of I. subquadratum based on unpublished data and experience and that they were capable of applying this knowledge to develop an economical and more suitable technology for their conditions.

Farmers' perceptions, knowledge, and management of coffee pests and diseases and their natural enemies in Chiapas, Mexico

Small farmers' perceptions of coffee Coffea arabica L. herbivores and their natural enemies, how those perceptions relate to field infestation levels, and pest management practices being implemented by members from two organic and nonorganic coffee grower organizations in the Soconusco region, southeastern Mexico, were analyzed through an interview survey, diagnostic workshops, and field sampling. The terms pest, disease, and damage were commonly used as synonyms. The major phytophagous species, as perceived by the interviewees, were Hypothenemus hampei (Ferrari), and to a lesser extent the fungi Corticium koleroga Cooke (Höhnel) and Hemileia vastatrix Berkeley & Broome. Among the nonorganic farmers, other nonpest-related constraints were regarded as more important. Awareness of the existence of natural enemies was low, despite more organic farmers have used the ectoparasitoid bethylid Cephalonomia stephanoderis Betrem against H. hampei. Labor supplied by household members was most frequent for pest control; only organic farmers exchanged labor for this purpose. The levels of infestation by H. hampei, Leucoptera coffeella Guérin-Méneville, and C. koleroga were lower within the organic coffee stands. However, a low effectiveness for pest control was commonly perceived, probably due to a feeling, among the organic farmers, of a low impact of their pest management extension service, whereas a lack of motivation was prevalent among the nonorganic farmers, shown by a concern with their low coffee yields and the emigration of youth. The importance of understanding farmers' perceptions and knowledge of pests and their natural enemies and the need for participatory pest management approaches, are discussed.

Effect of Beauveria bassiana and Metarhizium anisopliae (Deuteromycetes) upon the coffee berry borer (Coleoptera: Scolytidae) under field conditions

The effect of three strains of the fungus Beauveria bassiana (Balsamo) Vuillemin and two strains of Metarhizium anisopliae (Metschnikoff) Sorokin upon the coffee berry borer, Hypothenemus hampei (Ferrari), was studied in three coffee farms at different altitudes (450-1,100 m above sea level) in Soconusco, Chiapas, Mexico. The maximum average percentage mycosis varied according to altitude. At 450 m asl (El Rincon) mycosis was 14.3% for B. bassiana and 6.3% for M. anisopliae; at 880 m asl (Santa Anita) mycosis was 40.6% for B. bassiana and 12.6% for M. anisopliae, and at 1,100 m asl (Alpujarras) 33.9% for B. bassiana and 22. 1% for M. anisopliae. The effect of fungal mycosis through time was not significant (P > 0.01) in any of the farms, but there was a significant difference between the strains of the fungus (P < 0.01); the best strains being Bb25 and Ma4 at the lower altitude, Bb26 and Ma4 for the middle altitude and Bb26 and Ma4 at the higher altitude. Environmental factors such as temperature, relative humidity and rain were not correlated with the percentage mycosis caused by B. bassiana and M. anisopliae. However, in the case of B. bassiana there was a significant, positive correlation (P < 0.01) between the infestation levels of the pest and the mycosis response of the entomopathogen.