Coffee Pests and their Management

Transcription

1 offee Pests and their Management Juan F. Barrera El Colegio de la Frontera Sur, Tapachula, Chiapas, Mexico The perennial and evergreen nature of the coffee plant (Coffea spp.) favors attack by a number of insects and mites (Table 17, Figs. 73 and 74). All portions of the plants are susceptible to attack, and damage may appear at the seed bed, nursery, plantation, or in the warehouse. Certain pests affect the coffee plant only temporarily, while others live for several generations on the plant. In some instances, the attack may cause the death of the plant, but in most cases the pests only weaken the plant, reducing yield. When the bean is attacked, quality also may be affected. Insects constitute the most numerous group of coffee pests; of more than 850 species of insects that feed on coffee in the world, approximately 200 (23.5%) have been reported in the tropical and sub-tropical areas in America. Out of these, hardly thirty species, mostly indigenous, cause losses considered important. The pests and the seriousness of the problems they cause vary from one country to another, and from one area to another. The coffee pest that is considered the most important in tropical America is the coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae), now cosmopolitan but originating in Africa. The coffee leaf miner, Leucoptera coffeella Guérin-Méneville (Lepidoptera: Lyonetiidae), and the root mealybugs (Pseudococcidae) are causing serious problems in several countries. Bugs of the genus Antestiopsis (Pentatomidae), which are very harmful in Africa, have not yet been reported in the American hemisphere. Most of the insects that are found in coffee plantations are beneficial because they contribute to plant pollination, degrade organic matter, or feed on phytophagous organisms. A study conducted in Mexico showed that parasitic and C Coffee Pests and their Management predatory organisms, which regulate the populations of many pests, represented 42% of the total of species collected in a coffee plantation. For this reason, it is important to protect and maintain the natural enemies of pests, avoiding the indiscriminate use of chemical pesticides and some agronomic practices that are harmful to natural control. The goal of this section is to describe the biological and ecological characteristics of the main insects and mites of C. arabica L. and C. canephora Pierre ex Froehner, the damage caused by these pests, their natural enemies, and pest management in coffee growing countries of tropical America. The pests to be described are listed in Table 17, which also includes the parts of the plant that are damaged and the development stage of the coffee plant that they damage. The criterion applied to include these organisms in the category of major pests, was that they were reported in at least one of the manuals on coffee pests that have been published in Brazil, Colombia, Costa Rica, Cuba, El Salvador, Guatemala, Honduras, Jamaica, Mexico or Venezuela. Coffee Berry Borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae) Distribution This is the most serious insect pest of coffee worldwide. It originated in Africa. In the Americas, it is found in coffee plantations from Mexico to Brazil, including some countries in the Caribbean region such as Cuba, Jamaica, the Dominican Republic and Puerto Rico. Damage and Economic Importance Coffee berry borer (Fig. 73) is a direct pest because it causes direct damage to the product to be harvested, the coffee bean. The attacked green, ripe and dry fruits or berries usually show a hole 961

2 962 Coffee Pests and their Management Coffee Pests and their Management, Table 17 The most common phytophagous insects and mites of coffee in tropical America Taxon (scientific and common name) Country where the insect/ mite is reported as coffee pest Developmental stage feeding in/on the plant Acari: Tarsonemidae Polyphagotarsonemus latus Brazil Nymph, adult Leaves (Banks) Acari: Tenuipalpidae Brevipalpus sp. Brazil, Jamaica, Mexico Nymph, adult Leaves Acari: Tetranychidae Olygonychus coffeae Guatemala, Mexico Nymph, adult Leaves (Nietner) Olygonychus ilicis (McGregor) Brazil, Guatemala Nymph, adult Leaves Olygonychus punicae (Hirst) El Salvador Nymph, adult Leaves Olygonychus yothersi Colombia, Costa Rica, Nymph, adult Leaves (McGregor) Venezuela Coleoptera: Anthribidae Araecerus fasciculatus (DeGeer) Coleoptera: Cerambycidae Plagiohammus maculosus (Bates) Plagiohammus mexicanus Breuning Plagiohammus spinipennis (Thomson) Coleoptera: Curculionidae Brachyomus quadrinodosus (Lacordaire) All coffee growing countries in America Larva, adult Plant parts affected Bean Costa Rica, El Salvador, Guatemala, Honduras, Mexico Larva Stem, root Mexico Larva Stem, root Mexico Larva Stem, root Venezuela Adult Leaves Cleistolophus similis Sharp Costa Rica Adult Leaves Compsus sp. Colombia Adult Leaves Epicaerus capetillensis Sharp Guatemala, Honduras, Adult Leaves Mexico Hypothenemus hampei Mexico to Brazil, including Larva, adult Fruit, bean (Ferrari) Cuba, Jamaica, Dominican Republic, and Puerto Rico Lachnopus buchanani Cuba Adult Leaves Marshall Macrostylus boconoensis Colombia, Venezuela Adult Leaves Bordón Pantomorus femoratus Sharp Costa Rica Adult Leaves

3 Coffee Pests and their Management 963 Coffee Pests and their Management, Table 17 The most common phytophagous insects and mites of coffee in tropical America (Continued) Taxon (scientific and common name) Country where the insect/ mite is reported as coffee pest Developmental stage feeding in/on the plant Pantomorus godmani Brazil Adult Leaves Crotch Steirarrhinus sp. Costa Rica Adult Leaves Xylosandrus morigerus (Blandford) Coleoptera: Scarabaeidae Plant parts affected Mexico to Brazil Larva, adult Young stems, branches Anomala sp. El Salvador Larva Root Dyscinetus picipes Burmeister Cuba Larva Root Phyllophaga spp. Widely distributed in coffee Larva Root plantations in America Phyllophaga latipes (Bates) El Salvador Larva Root Phyllophaga menetriesi El Salvador Larva Root (Blanchard) Phyllophaga obsoleta El Salvador Larva Root (Blanchard) Phyllophaga sanjosecola Costa Rica Larva Root Saylor Phyllophaga vicina Moser Costa Rica Larva Root Hemiptera: Aphididae Toxoptera auranti (Boyer de Fonscolombe) Nymph, adult Tropical and sub-tropical areas of the Old World. Widely distributed in coffee plantations in America Leaves, buds and other tender parts of the plant Hemiptera: Coccidae Coccus spp. Mexico Nymph, adult female Aerial part of the plant Coccus hesperidum L. Guatemala, Mexico Nymph, adult female Aerial part of the plant Coccus viridis (Green) Brazil, Colombia, Costa Rica, Cuba, Ecuador, El Nymph, adult female Aerial part of the plant Salvador, Guatemala, Honduras, Jamaica, Mexico, Puerto Rico, Surinam, Venezuela Parasaissetia sp. Colombia Nymph, adult female Aerial part of the plant Parasaissetia nigra (Nietner) El Salvador, Guatemala, Puerto Rico, West Indies Nymph, adult female Aerial part of the plant Saisettia spp. El Salvador, Mexico Nymph, adult female Aerial part of the plant

4 964 Coffee Pests and their Management Coffee Pests and their Management, Table 17 The most common phytophagous insects and mites of coffee in tropical America (Continued) Taxon (scientific and common name) Saisettia coffeae (Walker) Saisettia olae (Oliver) Country where the insect/ mite is reported as coffee pest Brazil, Costa Rica, Cuba, El Salvador, Guatemala, Honduras, Mexico, Dominican Republic, Venezuela Brazil, Cuba, Guatemala, Mexico Developmental stage feeding in/on the plant Nymph, adult female Nymph, adult female Toumeyella sp. Venezuela Nymph, adult female Root Toumeyella liriodendri Guatemala Nymph, adult female Root (Gmelin) Hemiptera: Cerococcidae Cerococcus catenarius Fonseca Hemiptera: Diaspididae Plant parts affected Aerial part of the plant Aerial part of the plant Brazil Nymph, adult female Aerial part of the plant Chrysomphalus sp. Guatemala Nymph, adult female Aerial part of the plant Chrysomphalus dictyospermi (Morgan) Ischnaspis longirostris (Signoret) Lepidoshaphes beckii (Newman) Selenaspidus articulatus (Morgan) Hemiptera: Margarodidae Guatemala Nymph, adult female Aerial part of the plant Colombia, Cuba, Guatemala Nymph, adult female Aerial part of the plant Venezuela Nymph, adult female Aerial part of the plant Colombia, Ecuador, Mexico Nymph, adult female Aerial part of the plant Icerya purchasi Maskell Venezuela Nymph, adult female Aerial part of the plant Hemiptera: Ortheziidae Insignorthezia insignis Browne Brazil, Colombia Nymph, adult female Aerial part of the plant Praelongorthezia praelonga (Douglas) Hemiptera: Pseudococcidae Brazil Nymph, adult female Aerial part of the plant Brevicoccus sp. Guatemala Nymph, adult female Root Ceroputo sp. Costa Rica Nymph, adult female Root Dysmicoccus sp. Colombia, Ecuador Nymph, adult female Root Dysmicoccus bispinosus (Beardsley) Brazil, Guatemala, Honduras, Mexico Nymph, adult female Root Dysmicoccus brevipes (Cockerell) Costa Rica, El Salvador, Guatemala, Honduras, Mexico Nymph, adult female Root

5 Coffee Pests and their Management 965 Coffee Pests and their Management, Table 17 The most common phytophagous insects and mites of coffee in tropical America (Continued) Taxon (scientific and common name) Country where the insect/ mite is reported as coffee pest Developmental stage feeding in/on the plant Plant parts affected Ferrisia virgata (Cockerell) Brazil, Mexico, West Indies Nymph, adult female Aerial part of the plant Geococcus sp. Mexico, Venezuela Nymph, adult female Root Geococcus coffeae Green El Salvador, Guatemala, Nymph, adult female Root Honduras, Surinam Geococcus radicum Green El Salvador Nymph, adult female Root Neochavesia caldasiae Colombia Nymph, adult female Root (Balachowsky) Rhizoecus sp. Mexico, Venezuela Nymph, adult female Root Rhizoecus andensis Hambleton Colombia Nymph, adult female Root Rhizoecus coffeae Laing Costa Rica Nymph, adult female Root Paraputo sp. Guatemala Nymph, adult female Root Planococcus citri (Risso) Planococcus halli Ezzat & McLonnell Pseudococcus elisae (Borchsenius) Pseudococcus longispinus (Targioni-Tozzeti) Pseudococcus jongispinus Targioni-Tozzetti Brazil, Colombia, Costa Rica, Cuba, El Salvador, Guatemala, Honduras, Jamaica, Mexico, Puerto Rico Nymph, adult female Guatemala Nymph, adult female Root Guatemala Nymph, adult female Root Guatemala Nymph, adult female Root Root, aerial part of the plant Mexico Nymph, adult female Aerial part of the plant Puto sp. Costa Rica Nymph, adult female Root Puto antioquensis (Murillo) Guatemala Nymph, adult female Root Rhizoeccus campestris Guatemala Nymph, adult female Root (Hambleton) Rhizoeccus caticans Guatemala Nymph, adult female Root (Hambleton) Rhizoeccus kondonis Kuwana Guatemala Nymph, adult female Root Rhizoeccus nemoralis El Salvador, Honduras Nymph, adult female Root Hambleton Hymenoptera: Formicidae Acromyrmex spp. Venezuela Adult Leaves Acromyrmex coronatus (F.) Brazil Adult Leaves Acromyrmex octospinosus (Wheeler) Trinidad Adult Leaves

6 966 Coffee Pests and their Management Coffee Pests and their Management, Table 17 The most common phytophagous insects and mites of coffee in tropical America (Continued) Taxon (scientific and common name) Atta spp. Atta cephalotes (L.) Country where the insect/ mite is reported as coffee pest Guatemala, Ecuador, Nicaragua, Venezuela Colombia, Costa Rica, Mexico, Surinam, Trinidad Developmental stage feeding in/on the plant Adult Adult Plant parts affected Leaves Leaves Atta fervens Say Mexico Adult Leaves Atta insularis Guérin- Cuba Adult Leaves Méneville Atta laevigata Smith Brazil Adult Leaves Atta mexicana (Smith) Guatemala, Mexico Adult Leaves Atta sexdens (L.) Brazil Adult Leaves Atta sexdens rubropilosa Brazil Adult Leaves Forel Lepidoptera: Apateloididae Olceclostera moresca Colombia Larva Leaves (Schaus.) Lepidoptera Arctiidae Estigmene acrea (Drury) Colombia Larva Leaves Lepidoptera: Dalceridae Dalcera abrasa Herrich-Schaeffer Brazil Larva Leaves Zadalcera fumata Schaus Brazil Larva Leaves Lepidoptera: Elachistidae Stenoma cecropia Meyrick Colombia Larva Leaves Lepidoptera: Geometridae Glena sp. Brazil Larva Leaves Oxydia spp. Colombia Larva Leaves Oxydia saturniata Guenée Brazil Larva Leaves Lepidoptera: Limacodidae Phobetron hipparchia Brazil, Colombia Larva Leaves (Cramer) Sibine spp. Colombia Larva Leaves Lepidoptera: Lyonetiidae Leucoptera coffeella (Guérin- Méneville) Widespread wherever coffee is grown in the Neotropical area Larva Leaves Lepidoptera: Megalopygidae Megalopyge lanata (Stoll) Brazil, Colombia Larva Leaves Podalia sp. Brazil Larva Leaves

7 Coffee Pests and their Management 967 Coffee Pests and their Management, Table 17 The most common phytophagous insects and mites of coffee in tropical America (Continued) Taxon (scientific and common name) Lepidoptera: Noctuidae Agrotis spp. Country where the insect/ mite is reported as coffee pest Colombia, Costa Rica, Ecuador, El Salvador Developmental stage feeding in/on the plant Larva Plant parts affected Stems of small plants in germinating seedbeds or recently transplanted plants Agrotis ipsilon (Hufnagel) Brazil Larva Stems of small plants in germinating seedbeds or recently transplanted plants Agrotis repleta Walker Venezuela Larva Stems of small plants in germinating seedbeds or recently transplanted plants Feltia spp. Pseudoplusia includens (Walker) Spodoptera sp. Costa Rica, El Salvador, Venezuela Larva Honduras Larva Leaves Colombia, Costa Rica, Ecuador, El Salvador Larva Stems of small plants in germinating seedbeds or recently transplanted plants Stems of small plants in germinating seedbeds or recently transplanted plants Spodoptera eridania (Stoll) Venezuela Larva Stems of small plants in germinating seedbeds or recently transplanted plants Spodoptera frugiperda (Smith) Costa Rica, Brazil Larva Stems of small plants in germinating seedbeds or recently transplanted plants; leaves Trichoplusia ni (Hübner) Colombia Larva Leaves Lepidoptera: Psychidae Oiketicus geyeri (Berg) Brazil Larva Leaves Oiketicus kirbyi Brazil, Cuba Larva Leaves Lucas Lepidoptera: Saturniidae Automeris sp. Brazil, Colombia Larva Leaves Automeris complicata Walker Brazil Larva Leaves

8 968 Coffee Pests and their Management Coffee Pests and their Management, Table 17 The most common phytophagous insects and mites of coffee in tropical America (Continued) Taxon (scientific and common name) Country where the insect/ mite is reported as coffee pest Developmental stage feeding in/on the plant Plant parts affected Automeris coresus Boisduval Brazil Larva Leaves Automeris illustris Walker Brazil Larva Leaves Eacles imperialis magnifica Brazil Larva Leaves (Walker) Eacles masoni Schaus Ecuador Larva Leaves Lonomia circunstans (Walker) Brazil Larva Leaves Orthoptera: Gryllidae Paroecanthus guatemalae Guatemala, Honduras Adult female Stem, branch Saussure Paroecanthus niger Saussure El Salvador, Guatemala Adult female Stem, branch Orthoptera: Tettigoniidae Gongrocnemis sp. Guatemala Nymph, adult Leaves, buds, fruit pulp, beans Idiarthron atrispinum (Stål) Costa Rica, Guatemala Nymph, adult Leaves, buds, fruit pulp, beans Idiarthron subquadratum Saussure & Pictet Colombia, Guatemala, El Salvador, Honduras, Mexico Nymph, adult Leaves, buds, fruit pulp, beans on its apical portion. The hole is located at the center or ring of the berry s ostiole and the emission of sawdust can be observed through this hole. Its attack reduces the yield and affects the bean quality. Characteristic damage includes the rotting of developing beans as a result of saprophytic microorganisms that enter through the hole, the drop of young berries due to attack, and the loss of bean weight due to insect feeding. The borer can cause bean yield losses of 30 35% with 100% of perforated berries at harvest time; nevertheless, damage can be greater if harvest is delayed. All the commercial coffee varieties and species are attacked by this insect. However, it shows preference for C. canephora, and its multiplication is also higher on beans of this coffee species. Recently it was suggested that H. hampei serves as a vector for Aspergillus ochraceus Wilh., which produces ochratoxin A, a potent toxin that sometimes contaminates green coffee beans, roasted coffee, and coffee brews, including instant coffee. Description The egg is elliptical, crystalline and yellowish toward maturity. Its length varies from 0.52 to 0.69 mm. The larva is white-yellowish, without legs, with a C -shaped body and a wide thoracic region. The head is light brown, with visible and forward-extending mandibles. Visible hairs spread over the head and body. Females molt twice and males once. The length of the last larval instar is from 1.88 to 2.30 mm. The pre-pupa is similar to the larva, but its color is milky-white,

9 Coffee Pests and their Management 969 Coffee Pests and their Management, Figure 73 Some coffee pests: (a) Coffee berry borer, Hypothenemus hampei (Curculionidae) infesting a coffee berry; (b) Damage of coffee leaf by coffee leaf miner, Leucoptera coffeella (Lyonetiidae); (c) Root mealybugs (Pseudococcidae); (d) Scale insects on coffee leaf (Coccidae). its body is less curved, and it does not feed. The pupa is milky-white and yellowish towards maturity. Many of the adult s characteristics can be seen in the pupal stage. The pupa varies from 1.84 to 2.00 mm long. The adult is elongated with a cylindrical body slightly arched towards the end of the abdomen. It is about mm long and its body is bright black, although

10 970 Coffee Pests and their Management Coffee Pests and their Management, Figure 74 Some additional coffee pests: (a) Coffee branch perforated by Xylosandrus morigerus (Curculionidae); (b) Coffee stem attacked by a stem borer, Plagiohammus maculosus (Cerambycidae); (c) Aphids on coffee leaf; (d) Adults of a katydid, Idiarthron subquadratum; (Tettigoiidae) (e) Oviposition by a bush cricket, Paroecanthus (Gryllidae) on the stem of a coffee bush.

11 Coffee Pests and their Management 971 yellowish when emerging from the pupa. The head is ventrally located and is protected by the pronotum. The antennae are elbowed and clubbed at the ends. Mouthparts are the typical chewing type and the elytra are convex and possess longitudinal grooves that alternate with longitudinal series of bristles. Females have well-developed wings that allow them to fly, while the males wings are atrophied. Females are easily differentiated from males because they are larger. Biology and Ecology Adult females initiate the infestation. In general, a berry is infested by a single female. If the coffee bean is watery or milky, the insect tends to abandon it and the bean usually rots. But if the bean consistency is hard enough, the founding female constructs a gallery where she lays the eggs. The eggs are oviposited one by one, forming small groups within the coffee bean. The female lays from 1 to 3 eggs per day during the first days; afterwards, the egg laying diminishes gradually. Both the founding female and the larvae build tunnels in the bean, where they also feed. Pupation takes place within the coffee bean where the larva hatched. The duration of the biological cycle, from egg to adult, varies according to the temperature: 21 days at 27 C, 32 days at 22 C and 63 days at 19.2 C. As the first adult offspring appear, the population inside an infested bean typically consists of individuals in all stages of development, of which there are approximately 10 females for each male. Mating is conducted between siblings inside the bean. The mated females leave the bean where they developed to look for another where they will oviposit. Several generations occur while berries are available. After coffee harvest, the borer continues to reproduce in the non-harvested berries located on the plant and on the ground. In locations with low rainfall, where there is a clearly defined period between harvests, the adults find refuge in the black, dry berries. Adult females emerge massively from these old berries with first rainfall, initiating the infestation by attacking berries from the earliest flowerings of the new harvest. Natural Enemies Coffee berry borer is attacked by several natural enemies. Four parasitoid species from Africa are the best known: Prorops nasuta Waterston (from Cameroon, Ivory Coast, Zaire, Kenya, Tanzania, Togo, Uganda) and Cephalonomia stephanoderis Betrem (Ivory Coast, Togo) (both Hymenoptera: Bethylidae), and two solitary ectoparasitoids of the larva, pre-pupa and pupa, Heterospillus coffeicola Schimideknecht (Hymenoptera: Braconidae) (Cameroon, Zaire, Kenya, Tanzania, Uganda) (a free-living wasp that deposits a single egg near a borer s egg cluster in a recently attacked berry) and Phymastichus coffea LaSalle (Hymenoptera: Eulophidae) (Togo, Kenya) (a gregarious endoparasitoid of H. hampei adults which parasitizes the borer during the berry perforation). Other parasitoids that have been reported attacking H. hampei include Aphanogmus dictyna (Waterston) (Hymenoptera: Ceraphronidae) (Uganda), Sclerodermus cadavericus Benoit (Hymenoptera: Benthylidae) (Uganda, Zaire, Kenya), Cephalonomia hyalinipennis Ashmead (Mexico) and Cryptoxilos sp. (Hymenoptera: Braconidae) (Colombia). In Brazil and Colombia, there are reports of an undescribed species of Cephalonomia parasitizing H. hampei. Some of the predators that have been recorded include Dindymus rubiginosus (F.) (Hemiptera: Pyrrhocoridae) (Indonesia), Calliodes, Scoloposcelis (Hemiptera: Anthocoridae) (Colombia), and Leptophloeus sp. near punctatus Lefkovich (Coleoptera: Laemophloeidae) (Togo, Ivory Coast). However, most of the predators of H. hampei reported from around the world (most of them anecdotal records) have been ants (Hymenoptera: Formicidae), including Azteca instabilis (F. Smith),

12 972 Coffee Pests and their Management Crematogaster curvispinosa Mayr, C. torosa Mayr, Dolichoderus bituberculatus Mayr, Pheidole radoszkowskii Mayr, and Solenopsis geminata (F.). Unknown species of Azteca, Brachymyrmex, Paratrechina, Pheidole, Prenolepis and Wasmannia have been recorded as well. Several entomopathogenic fungi attack the coffee berry borer, but Beauveria bassiana (Balsamo) Vuillemin is the most common species infecting H. hampei adults under natural conditions. Other fungi recorded infecting H. hampei are Fusarium oxysporum Schlechtend, F. avenaceum (Fr.) Sacc., Hirsutella eleutheratorum (Nex ex Gray) Petch., Metarhizium anisopliae (Metschnikoff) Sorokin, Nomuraea rileyi (Farlow) Samson, Paecilomyces amoenoroseus (Hennings) Samson, P. farinosus (Holm. ex S.F. Gray), P. fumosoroseus (Wize) Brown & Smith, P. javanicus (Friederichs & Bally) Brown & Smith, P. lilacinus (Thom.) Samson, and Verticillium lecanii (Zimmerman). Some of these fungi, such as M. anisopliae and P. lilacinus, have been isolated from H. hampeiinfested berries collected from the soil. Metaparasitylenchus hypothenemi Poinar (Tylenchida: Allantonematidae), an entomopathogenic nematode attacking H. hampei adults, has been reported in Mexico and appears to have a wide distribution in coffee plantation in Mexico and Central America This nematode cause sterility in female borers. The natural parasitism by an undescribed species of Panagrolaimus (Rhabditida: Panagrolaimidae) has been reported in H. hampei in India and Mexico. M. hypothenemi and Panagrolaimus sp. were found infecting the same H. hampei adults in Mexico. Species from Heterorhabditidae and Steinernematidae (Rhabditida) are able to infect H. hampei in the laboratory, but this has not been observed in the field. In Colombia, infections in the coffee berry borer caused by bacteria such as Bacillus sp. and Serratia sp. were observed. Also, infections of proteobacterium Wolbachia in H. hampei adults have been reported from samples around the world. The microsporidian Mattesia sp. was observed in a population of laboratory-reared insects. Management An integrated pest management strategy is used against the coffee berry borer. The principal tactics are cultural control, biological control, use of traps baited with attractants, and chemical control with synthetic insecticides. Sampling infested berries is used for pest control decision-making. Sampling Infested Berries The proportion of infested berries is calculated based on the following sampling protocol: in an area of 1 5 ha, 20 uniformly distributed sites are selected; at each site five coffee plants in a row are selected; 20 berries of each coffee plant are examined (without tearing them off), and the number of perforated berries is recorded. Cultural Control There are a number of cultural practices that may be used to minimize damage by borers. The berries left on the plant before maturity and on the ground after harvest are collected and boiled for 5 min to eliminate the borers in them. This practice is also called manual control or rere. Weeds are controlled after the harvest in order to facilitate the collection of berries from the ground and to increase the mortality of H. hampei by dehydration of the berries. The coffee and shade plants are pruned to create less favorable environmental conditions for multiplication of the borer. Coffee plant density is decreased because high sowing densities favor infestation. The coffee plants are fertilized so that they have more uniform flowerings. Varieties with the same fruiting pattern are used because the early flowering varieties are an infestation source for late flowering varieties; however, coffee varieties or species which flower earlier or later than the main variety can be used as trap crops, if managed properly. The harvest is conducted as the fruits ripen.

13 Biological Control The natural enemies most often used against the borer in tropical America have been the parasitoids C. stephanoderis, P. nasuta and P. coffea, and the entomopathogenic fungus B. bassiana. These three parasitoids were introduced to tropical America from Africa. They are established in most of the countries where they have been released. Nevertheless, classical biological control with these African parasitoids has not been sufficient to reduce the borer population below the economic injury level. Yearly inoculative and inundative releases of parasitoids have been used with better results. However, inundative releases are expensive because mass rearing methods and facilities have not been developed for area-wide releases. Parasitoids are produced for inoculative releases in laboratories where the borer is reared mostly in parchment coffee (35% humidity) for use in rearing the parasitoids. A rearing system for H. hampei in an artificial diet has been developed; however, its application for mass production of parasitoids is not fully employed. An alternative and less intensive rearing system to produce parasitoids for inoculative releases is production of the parasitoids in rural areas, also known as parasitoid rural rearing. In this system, the coffee growers rear the parasitoids at their farms or communities. Such rearing is conducted using coffee berries infested by the borer in the field. Regardless of the rearing method used, annual releases of parasitoids are needed to manage the borer population. The use of B. bassiana for borer control is more developed than is the use of parasitoids. Its success has resulted from the relatively easy propagation, formulation and application of this fungus. Strains of B. bassiana are commonly collected for mass production from infected H. hampei females in the field. Rice grains are used as the propagation substrate for this entomopathogen. The fungus requires high relative humidity for germination of the spores and it is very susceptible C Coffee Pests and their Management to sunlight. Early in the morning is the most effective time to apply it in the field, when the borer is starting to penetrate the coffee berry. Insect Traps Traps are used for monitoring and control of the coffee berry borer. They are made using 2 L plastic bottles into which one or more windows have been cut to allow the entry of flying females. Borers are attracted by a mixture of methanol and ethanol (1:1 or 3:1) and they are caught and drowned in the water placed at the bottom of the trap. Typically, traps are deployed per hectare. Each trap is suspended from a branch of a coffee plant at m above the ground. Borers captured are removed from the traps and counted weekly. The best time to use the traps for H. hampei control is after the harvest, during the massive emergence of females from old berries. Better results for suppression of insect infestation in the next harvest can be obtained by combining the use of traps with strict sanitation. Chemical Control There are several chemical insecticides used for borer control, among which endosulfan is outstanding for its ability to cause high mortality of H. hampei. However, this organochlorine insecticide is being seriously questioned for negative side effects (it is highly toxic to fish and bees, and it causes secondary pest outbreaks by eliminating the natural enemies); borer resistance (apparently this pest is not resistant to endosulfan in tropical America; nevertheless, there is concern about the development of resistance, as in the case of New Caledonia); and sanctions in the international market due to the possible presence of residues in the coffee bean. The insecticide should only be used if the borer population reaches the economic threshold. The best time for spraying is when the adult borer starts 973

14 974 Coffee Pests and their Management penetrating the fruit, at the so-called semi-consistency stage of development (about 20% dry weight in the bean). This period varies, according to the temperature, from 90 to 140 days after the main flowering. Formerly, treatments were throughout the plantation, but now sprays are directed only at infested areas. Coffee Leaf Miner, Leucoptera coffeella (Guérin-Méneville) (Lepidoptera: Lyonetiidae) Distribution This species is found in the Neotropics: Mexico, Central America, South America and the Caribbean region. It is widespread wherever coffee is grown. Damage and Economic Importance In some areas of tropical America, the coffee leaf miner is considered to be the principal insect pest of coffee; certainly this is the case in some coffee-growing areas in Brazil. Leaves are the only plant organs damaged by this insect. The damage is caused by the larva. Four larvae per leaf may cause leaf drop. The affected leaves show irregular light-brown spots. If the damaged surface of the leaf is rubbed, the leaf separates into two layers and between them is found a small white worm, from 2 to 5 mm in size. The coffee leaf miner lesions may be confused with the symptoms of Anthracnose (Colletotrichum sp.), but in the latter case the leaf layers do not separate when rubbed. Four months after flowering, a reduction in the rate of growth of the coffee berries and an increase in leaf production take place; this allows the plant to compensate for the damage caused by the miner. But when the fruit growth starts again, if there is more than one leaf miner lesion per leaf it will result in economic damage. The damage increases if simultaneously the plant is under drought stress. Attack of coffee by leaf miner can cause severe defoliation. In Ecuador, defoliation between 70 and 90% has been reported on C. arabica and from 30 to 40% on C. canephora. The lack of leaves on the plant reduces the photosynthetic activity, and consequently the availability of nutrients for the fruits. In Brazil, when 94 95% of the leaves were mined, a reduction in yield between 68 80% has been observed. Description The egg is oval, translucent yellow and similar to a flattened volcano in profile. It is 0.28 mm long, 0.18 mm wide, and 0.08 mm tall. The larva has a dorsoventrally flattened body with a more pronounced flattening of the head and the first thoracic segment. The true legs are found on the 1st, 2nd and 3rd thoracic segments but four pairs of prolegs occur on the 6th, 7th, 8th and 13th abdominal segments. It has four larval instars. The larva attains a length of 4.5 mm. The pupa is white in the initial stage and ochre towards maturity, except for the dorsal portion, which remains white. The pupa is covered by a white cocoon which resembles an elongated H or X. The adult is a small moth between 2.0 and 3.0 mm long with its body covered by silvery scales. The antennae are long and thin. The front wings possess a gray oval point distally, surrounded by a black line and edged by a yellow stripe that extends along the margin. Males tend to be slightly smaller than females. Biology and Ecology The female usually lays its eggs irregularly on the upper surface of the darkest, most mature leaves, particularly on the middle and lower parts of the coffee plant. Eggs are laid individually or in small clusters of up to seven eggs, with a total fecundity that varies between 30 and 80 eggs. Upon hatching, the larva makes a semi-circular cut at its base

15 and penetrates rapidly into the leaf, where it moves about, mining the palisade parenchyma tissue. When ready to pupate, the fully developed larva leaves the gallery very early in the morning, making a semi-circular cut on the face of the leaf, through which it slips down by a silk thread which it secretes from the mouth. Cocoon formation and pupation take place on the lower face of the coffee leaf, often on a curvature of the leaf or close to a protruding vein. The duration of the life cycle, from egg to adult, lasts between 25 and 75 days, depending on the temperature. Several generations occur annually, particularly in coffee plantations with full sunlight or only lightly shaded. The abundance of L. coffeella is significantly affected by the onset of rainfall, and by natural enemies, which are very numerous after the end of the dry season. Natural Enemies The coffee leaf miner is attacked by a large number of parasitoids; predators and some insect pathogens have also been recorded. More than 20 morphospecies of parasitoids wasps (Hymenoptera) have been reported in tropical America. Eulophidae are the most common parasitoids of L. coffeella; this group is largely unknown because keys for neotropical species do not exist. In Mexico, Neochrysocharis was the genus with the greater number of morphospecies, and also the one that was collected most frequently. It was followed, in order of abundance, by Pnigalio, Closterocerus, and Zagrammosoma. Of two braconids collected in Mexico, Stiropius letifer (Mann) was the most abundant and most widely distributed. Wasps (Vespidae) are the most important predators of coffee leaf miner in Brazil, but in Mexico, the most important predators are ants (Formicidae). The bacteria Pseudomonas aeruginosa (Schroeter) Migula and Erwinia herbicola (Löhnis) Dye, and the fungus Cladosporium sp., have been reported infecting L. coffeella. Management C Coffee Pests and their Management There are several useful approaches to management of coffee leaf miner. population. Sampling is recommended prior to initiating chemical control. Sampling Damaged Leaves The recommended sampling protocol follows: sampling is initiated when the coffee flowers, and is conducted monthly until the berries stop growing. The coffee plantation to be sampled is divided into areas not larger than one hectare. The sampling is conducted by selecting a zigzag path across the coffee plantation and by selecting 12 coffee plants at random. From each coffee plant, 25 leaves are selected at random, and the number of leaves with mines is recorded. The first two pairs of leaves at the tip of the branches are not sampled. Cultural Control The shade canopy of coffee plantation should not be trimmed immediately after harvest; it should be thinned only when the onset of the rainy season is imminent. Adequate soil fertilization is important. Thick mulch coverage of the soil should be maintained. High coffee plant densities should be avoided. The coffee plant should be pruned to stimulate vigorous growth. Damaged leaves should be collected and placed in containers that allow the escape of parasitoids but not of the coffee leaf miner. Biological Control The introduction of natural enemies into new areas has not been widely explored. The most important action conducted so far has been to protect the already existing natural enemies by 975

16 976 Coffee Pests and their Management avoiding the use of broad-spectrum, residual contact insecticides. The natural control exerted by the coffee leaf miner s natural enemies varies from 2 to 70%; however, in most cases it is unnecessary to resort to the use of chemical control. Regrettably, the use of chemical insecticides may eliminate a large portion of the beneficial organisms, causing pest resurgence and making it difficult to implement control. In certain countries like Honduras, high and recurring L. coffeella infestations have diminished significantly when the use of chemical control is not applied for several years and the beneficial fauna is restored. This supports the idea that coffee leaf miner control should not be based on use of insecticides in order to avoid disrupting the actions of parasitoids and predators. Chemical Control Numerous chemical insecticides can be used for suppression of L. coffeella and protection of foliage. These products include both organophosphate and pyrethroid insecticides. They are inexpensive and can be applied at the same time with other agrochemicals, but they are highly toxic and they are more likely to cause ecological disturbances. Organophosphorates are often applied twice at an interval of days, with an additional application in cases of severe attack. In the case of pyrethroids, one or two applications at an interval of days are recommended. The application of granular insecticides with systemic action to the soil is also recommended in cases where it is difficult to apply foliar sprays. Soil applications interfere much less with the natural enemies of the coffee leaf miner, and this approach can be used to control pests and soil diseases simultaneously. Granular insecticides should be shallowly buried at the drip line of the plant once a year during the rainy season. Where this type of product is used, it is recommended that harvest occur 90 days after application. Root Mealybugs (Hemiptera: Pseodococcidae) Distribution Root mealybugs are found in Neotropical countries where coffee is grown. The principal root mealybugs affecting coffee plants in tropical America are shown in Table 17. Damage and Economic Importance These insects attack the coffee plant roots and some species also affect the foliage. The foliage of attacked coffee plants appears withered, the color of the leaves fade, and they have copper, brown or necrotic edges. Additionally, total or partial leaf drop may occur. These symptoms are more evident during the dry season. In case of serious attacks by Dysmicoccus bispinosus (Beardly), a thick, cork-like, dark crust covers the main and secondary roots; the attacked roots lose their absorbent root hairs. Heavily attacked plants perish. Infestation appears to be associated with ants (Formicidae). The symptoms may be confused with the symptoms of fungal diseases and with physiological plant problems. In the case of Neorhizoeccus coffeae (Laing) and D. brevipes (Ckll.) infestations, the branches turn whitish and the affected root seems to be covered with flour, the crust separates easily, and considerable deteriorated tissue appears. The attacked plants have little anchorage and are easily dislodged. Root mealybugs have become important coffee pests in some areas of tropical America during the last 20 years. In Guatemala, the most harmful species is D. bispinosus; in Costa Rica, N. coffeae and D. brevipes; in El Salvador, D. brevipes, Rhizoeccus nemoralis Ham. and Geococcus coffeae Green; and in Colombia, Chavesia caldasiae (Balachowsky). At some coffee plantations in Colombia, Planococcus citri (Risso) has also appeared as a pest, causing up to 30% yield loss in the attacked trees. Other forms of damage caused by root mealybugs include excessive extraction of potassium, destruction of the absorbent root hairs,

17 Coffee Pests and their Management 977 development of small rotting areas which tend to atrophy, and enhanced entry of plant pathogens. This damage creates a general condition of weakness, slow growth and plant death in many cases. Dysmicoccus brevipes weakens the coffee plants but it rarely kills them. In Costa Rica, plants with more than 20 mealybugs per liter of soil are more susceptible to infection by the fungus Cercospora coffeicola Berk & Cooke. Damage is more apparent on nutrient-deficient soils, and where weeds are abundant. Plants in seed beds and tree nurseries are also attacked. The varieties of C. arabica grown in Central America (e.g., Caturra, Catuaí, Bourbon) are susceptible to the mealybug attack, while tolerance has been observed on C. canephora, C. dewevrei De Wild. & Durand, and C. excelsa Chev. Description Mealybug eggs are small (0.5 mm). The nymphs are oval, slightly swollen, usually white, yellow or pinkcolored, and covered by a white waxy-mealy dust with waxy filaments projecting laterally. The female nymphs molt three times, and the males, contrary to the females, form a waxy cocoon in the third instar, where they pupate. The adult females have no wings and they are similar to the nymphs but larger. Smaller species, such as Geococcus and Rhizoecus, are from 1.5 to 2.0 mm long and the larger ones, such as Dysmicoccus and Pseudococcus, are from 2.5 to 5.0 mm long. Males are white, fragile-looking, smaller than the females, and they possess a pair of wings and a pair of terminal filaments. Biology and Ecology Mealybugs generally live attached to the coffee root, forming numerous colonies. Their reproduction may be sexual or parthenogenetic (partial or total). Eggs are laid in groups and covered by a layer of cotton-like wax or by an egg sac of crystalline wax filaments. A single female may deposit eggs. Other species, such as Pseudococcus adonidum (L.) are oviparous. Females die shortly after the eggs hatch. Upon eclosion, the small nymphs start looking for an appropriate place to settle on the plant root; at the selected site, they insert their mouthparts, and feed by suctioning the sap from the root. Some of them settle down permanently on a site until they reach maturity, and others may change their feeding site by moving short distances. Depending on the type of soil, the humidity, aeration and age of the coffee plant, they usually place themselves between 10 and 60 cm under the soil surface, their population diminishing as the soil depth increases. Different species prefer different parts of the root. For example, D. brevipes and R. nemoralis prefer the main and the lateral roots, while G. coffeae attacks the absorbent roots; the smaller species attack the whole root system near the soil surface. As they feed and develop, the nymphs and adults excrete their characteristic waxy cover and form compact colonies. Mealybugs excrete sugary substances (honeydew), which supports the growth of fungi (i.e., Bornetina), which contribute to formation of the thick, cork-like, dark crust covering and sheltering the mealybug colony; a succession of crusts give a knotty appearance to the root. The sugary substances also attract certain ant species, which live in a symbiotic association (trophobiosis) with the mealybugs. In exchange for the sugary foodstuff, the ants give them protection and transportation from one root to another and from one plant to another. The ants that associate with mealybugs in South America and in some of the Caribbean Islands are in the genus Acropyga. In Colombia, the Hope ant (A. robae Donisthorpe) and the Amagá ant (A. fuhrmanni Forel) are associated with N. coffeae and C. caldasiae, respectively. In Guatemala, D. bispinosus seems to be associated with the presence of the ant Solenopsis geminata (F.). P. citri does not produce large quantities of sugary excretions when it lives on the plant roots, and is not attractive to ants. In certain cases, the mealybugs have lived for more than a year in the absence of ants. The life cycle, from egg to adult, requires from 30 to 120 days, according to the species and the

18 978 Coffee Pests and their Management temperature. Five generations develop per year in the case of D. bispinosus. Root mealybugs develop better during the rainy season, particularly in low or medium altitude plantations in Central America. Other conditions that favor their development are sandy, acid ph, and medium moisture soils. In Colombia, the damage caused by Rhizoecus sp. seems to increase in old, poorly fertilized plantations, and in Guatemala D. bispinosus is found most frequently in 1 5 year-old plantations. Mealybugs are polyphagous, also attacking other plants such as shade trees (Inga spp.), cassava (Manihot esculenta Crantz), sugarcane (Saccharum), banana trees (Musa), lemon trees (Citrus) and some herbs that grow on the coffee plantation. In Costa Rica, Anredera ramosa (Moq.) Eliasson is an alternate host of D. brevipes; in El Salvador, D. bispinosus has been found associated with Lantana camara L. Natural Enemies In general, the literature on coffee mealybugs in tropical America does not make reference to their natural enemies. In Cuba, Coccidoxenoides peregrinus (Timberlake) (Hymenoptera: Encyrtidae) is cited as a solitary, primary endoparasite of the pseudococcid complex in coffee. Other natural enemies of mealybugs reported in Cuba are Diadiplosis cocci Felton (Diptera: Cecidomyiidae), Leptomastix dactylopii Howard (Hymenoptera: Encyrtidae) and Signiphora sp. (Hymenoptera: Signiphoridae). Management There are management options for mealybugs, but insecticides are normally used once pest populations develop. Sampling Sampling should preferably be conducted on young coffee plantations (up to 6 years old). Plants near ant nests should be examined critically; from 15 to 20 plants/ha should be checked, paying more attention to those that are close to the ant nests and/or possess yellow leaves. The surrounding shade trees and bushes should also be checked. The plants are checked by moving the stems in all directions in order to gain visibility of the base of the roots. Cultural Control Mealybugs should not be present in the seed bed and tree nursery. The limits of any infestation sites should be determined and marked. Adequate fertilization should be provided, including addition of organic matter to the soil. Physical conditions of the soil should be improved in order to avoid floods. Planting coffee trees on land previously supporting plants that are highly susceptible to mealybugs (e.g., cassava, sugarcane) should be avoided. Alternate host plants should be eliminated from the plantation. Severely damaged plants should be removed and burned. Biological Control This is practically unexplored in the coffee growing countries of tropical America. Plant Resistance to Insects In Guatemala, some research has been conducted which supports the use of plants grafted on resistant rootstocks of C. canephora (genotypes 3757, 3754, 3751, 3581, 3752 and 3756) and C. dewevrei. Chemical Control Systemic organophosphorate and carbamate insecticides produce good results, although they are expensive. The presence of mealybugs in seed beds or on plants younger than 1 year old is sufficient

19 Coffee Pests and their Management 979 justification for insecticide application. On plantations older than 3 years, insecticide application is made if more than 1.6 colonies per plant, on average, are found. In no case should the damage be allowed to exceed 25% of the absorbent roots. Insecticides are applied on the drip line of the plant if the damage is on the small roots. If the damage is on the main root a funnel-shaped hole should be made around the tree trunk, the insecticide should be poured in and the hole should be covered again with soil, adding also a layer of dead leaves. Application of granular insecticides is made at the beginning of the rainy season or 3 months before starting the harvest. Scale Insects, Mealybugs and Related Foliage Pests (Hemiptera) Distribution Different scale insects, mealybugs and related foliage pests live on the coffee plant. The geographic distribution of some is restricted to a few countries of tropical America, whereas others are distributed more widely. Some are reported attacking the coffee plant only in South America, others only in Central America or the Caribbean (Table 17). Damage and Economic Importance Scale insects, mealybugs and related species attack the aerial part of the coffee plant and, in some species, also the root (e.g., Planococcus citri [Risso]). The leaves, fruit, branches and young tissues of the aerial part of the attacked coffee plant often support colonies or groups of circular, oval or elongated scales, which may be flattened or swollen, with a soft or hard consistency. In other cases, colonies of insects have a soft body covered with white, cotton-like filaments. These insects cause damage by removing large quantities of sap, which causes plant malnutrition. Also, sticky honeydew and blackish molds can be found covering the foliage. When Capnodium (sooty mold) and Meliola (black mildew) fungi grow on the honeydew excreted by the scales, they interfere with photosynthesis. Ants are present where scale insects are feeding. In cases of severe attack, a dirty appearance on the plant, general weakening, growth delay, yellowing and drop of foliage and fruit are observed. With the articulated scale, Selenaspidus articulatus (Morgan), old attacks may be recognized because the site where the scales were located turns yellow or discolored, resembling infection by the coffee rust fungus (Hemileia vastatrix Berk. and Br.). Some species, such as the green scale, Coccus viridis (Green), are considered to be quite important to coffee production, though some attack a number of different cultivated plants. Severe infestations of C. viridis may kill young tree nursery plants. The incidence of these pests is highest on coffee plantations lacking adequate shading. Pest Description The following cases are presented as examples: C. viridis adult females are motionless, oval, sometimes asymmetric, very flat and pale yellow. They have some black spots centrally, and they tend to be soft and elastic. They are about 2.2 mm wide and 4.0 mm long. The presence of males is very rare. Saisettia coffeae (Walker) adult females are motionless, almost spherically shaped and dark brown. They are mm in diameter. The males are winged. P. citri adult females are mobile, oval, pale yellow or dark orange, with very clear segments on the body, and 4.0 mm in size. They are covered with a dusty white glandular secretion except for a longitudinal stripe dorsally. They have filaments laterally. Males are smaller (1.0 mm), violet to yellow in color, and they have well-developed wings. Biology and Ecology The biology of these insects varies among species and can be quite complex. The first instar

20 980 Coffee Pests and their Management has legs and antennae and is very active. To feed, the insects attach and insert their mouthparts. After the first molt, they generally lose their legs and antennae and the insect becomes sessile. By then, it begins to secrete a waxy, scale-shaped layer that covers the body. In the case of scales of the family Diaspididae, this layer of scale is almost always separated from the insect s body. Adult females remain under this cover and they produce their eggs or directly give birth to the nymphs therein. The location on the plant, and the age of the plant they prefer to attack, depends on the species of scale: C. viridis is commonly located along the leaf veins, on the back of the leaves, on young buds and on seed bed coffee fruits of nursery plants; S. articulatus is found mainly on the leaves and fruits of production plants; the round scale, Parasaissetia sp., mostly attacks the stems and branches of coffee plants younger than 1 year; the black scale, Ischnaspis longirostris (Signoret), infests the leaves, branches and fruits of old, poorly attended coffee plantations; Cerococcus catenarius Fonseca gathers in the form of a line or chain along the trunks and branches; P. citri attacks new branches, leaves, flower buds, fruit peduncles and fruits; Orthezia spp. attack branches, leaves and fruits, mostly of robusta coffee in Brazil. The males develop very much like the females except that in the last stage, before transforming into adults, they go through a pupal stage; the wings develop externally over the pupa. Most of the scales reproduce parthenogenetically. Some species are oviparous (S. coffeae, S. olae [Oliver]) and others are viviparous (Coccus hesperidum L.). The total number of eggs produced per female varies among the species; for example: C. viridis, between 50 and 600 eggs; Orthezia praelonga Douglas, more than 200 eggs; C. catenarius, about 900; S. coffeae can lay up to 1,600 eggs. The complete life cycle, from egg to adult, lasts between 40 and 60 days. The scale insects are more abundant during the dry season and at the onset of the rainy period. Hard rains and natural enemies are important factors in the mortality of these pests. Natural Enemies These insects are susceptible to a large number of parasites, predators and pathogens as natural enemies. Management Sampling During the dry season, inspections should be conducted to check for the presence of scales and related species in the coffee plantation, as well as on other plants cultivated nearby or at the same time. Cultural Control The nursery shading should be reinforced during the dry season. Affected plants should not be transplanted. Weeds should be suppressed. The pests should be kept under control on host plants existing in or near the coffee plantations. Sanitary pruning should be performed to eliminate (by burning) old and unproductive branches infested by the pests. Biological Control Natural enemies should be protected and preserved, using insecticide only if necessary. Chemical Control Chemical control is directed only at infested plants, after checking to determine that the scale colonies are alive. For better control, mineral oil is added to the insecticide solution, with applications made every 15 days until the problem is corrected. The oil should not be used during flowering or during sunny periods of the day. During the rainy season, granulated insecticides may be used.