Rearing (: ) on Artificial Diet and Cladodes1

Orville G. Marti, Ronald E. Myers, and James E. Carpenter

U.S. Department of Agriculture, Agricultural Research Service, Crop Protection and Management Research Laboratory, PG Box 748, Tifton, Georgia 31793 USA

J. Entomol. Sd. 43(1): 95-106 (January 2008) Berg, is an invasive that threatens Abstract The , Cactob/astiS cactorum economically and ecologically important native cacti in and the U.S. Southwest. The insect presently occurs along the coastal U.S. from Charleston, SC, to Dauphin Island, south of Mobile, AL, and in the interior of . Current control and eradication tactics include manual destruction of infested cactus and the Sterile Insect Technique (SIT), which involves the release of irradiated cactus to mate with wild moths and produce sterile offspring. The ability to rear the cactus moths in the laboratory has been crucial in research and development of survey and control techniques. Procedures for rearing the cactus moth in the laboratory on cactus cladodes and artificial diet are described and provide a foundation for the further development of mass-rearing protocols. Cactaceae, mass rearing, artificial Key Words CactoblastiS cactorum, Pyralidae, Opuntia, diet, , sterile insect technique

The cactus moth, CactoblastiS cactorum Berg (Lepidoptera: Pyralidae: Phyciti- nae), is an invasive species first detected in the continental in Florida in 1989 (Habeck and Bennett 1990, Zimmerman et al. 2001). It has since been detected in the interior of the Florida peninsula, up the east coast of the US as far north as Charleston, SC, and along the coast of the Gulf of Mexico as far west as Dauphin Island, south of Mobile, AL, (Soils et al. 2004, Carpenter, pers. obs.). This insect is recognized as a serious threat to native Opuntia species in the US and particularly in Mexico (Perez-Sandi 2001, Stiling and Moon 2001), where Opuntia species are widely used as food, livestock fodder, medicine, dye production, and fencing (Vigueras and Portillo 2001). Most importantly, Opuntia and other cacti are major components of local ecosystems in Mexico and the US Southwest. To avert the economic and ecological consequences that C. cactorum could have in Mexico and the U. S. Southwest, the US Department of Agriculture, in cooperation with Mexico, has developed procedures for using the Sterile Insect Technique (SIT) is reared in large numbers on against C. cactorum. In the SIT program, C. cactorum artificial diet in the laboratory and adults are irradiated with Co 60 , which produces complete sterility in females and partial sterility in males. Irradiated insects are then released in large numbers at the leading edge of the invasive population and at times

Received 18 June 2007; accepted for publication 16 July 2007. Mention of a product does not constitute an endorsement of its use by USDA. 2Address inquiries (email: Jim.Carpenter@ ars.usda.gov)

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which coincide with the presence of wild individuals available for mating. When irra- diated males mate with wild females, the Fl progeny of these matings are sterile. In order for the SIT program to succeed, large numbers of moths must be reared from egg to adult on artificial diet in a quarantined rearing facility (Carpenter et al. 2001). Mortality from disease in the rearing colony disrupts the SIT program by reducing the numbers of insects available for release. Disease problems have been more severe in insects reared on artificial diet than in those reared on Opuntia cladodes (Marti et al. 2007). Research is presently underway to develop an improved artificial diet which will be comparable to cactus cladodes in its ability to sustain the laboratory production of large numbers of C. cactorum for release in the SIT program. Until a satisfactory artificial diet has been fully developed and validated for several continuous genera - tions, we rely on Opuntia cladodes as the primary food source for Cactoblas f/s larvae. Here we provide a detailed description of the current procedures used at USDA- ARS Crop Protection and Management Research Unit (CPMRU) laboratory for rear- ing C. cactorum on artificial diet and on Opuntia cladodes. The components of the diet, its preparation, and the techniques for rearing and handling larvae and adults are the subject of ongoing research in an effort to develop the best procedures at lowest cost. The diet components in particular are subject to change and improvement.

Rearing Protocol

Mass-rearing of C. cactorum on Opun f/a cladodes and artificial diet are fundamen- tally similar, differing principally in the source of the diet, with the former collected from natural host in the field and the latter prepared in the laboratory from ingredi- ents purchased commercially. From the time that cocoons are gathered at the end of the larval period until hatch of eggs in the succeeding cycle, procedures and equip- ment for harvesting and handling of cocoons and pupae, management of adults, and incubation of eggsticks are identical, or nearly so. We have, therefore, provided parallel descriptions of the respective procedures for the cladode-reared and diet- reared colonies, and combined as much as possible the subsequent descriptions of similar or identical procedures. Rearing Cactoblastjs cactorum on Opuntia cladodes. Whereas artificial diet is prepared in the laboratory from commercially purchased components, the use of Opuntia cladodes (=pads) as food for C. cactorum larvae requires a reliable year- round source of suitable cladodes. Not all Opuntia species are a suitable food source for C. cactorum (Perez-Sandi 2001). Opuntia -indica (L.) and 0. stricta (Haworth) are the most common and best-suited species in the vicinity of Tifton, GA, and can be located in the wild, usually along fence rows where they are often planted for orna- mental value. Old stands may be composed of many individual plants, either planted by property owners or propagated from seeds or fallen cladodes. The size of the laboratory colony should be scaled to the availability of wild plants and sites should be visited on a rotating basis to avoid overharvesting of cladodes and to allow time for new growth. Alternatives to harvesting of cladodes from the wild include farming of Opuntia locally or contracting with growers to have cladodes shipped from areas where the plants are more abundant. Before any new source of Opuntia is used in rearing the laboratory colony, tests should be conducted on a small portion of the colony to verify the acceptability and suitability of the cladodes. Collect mature ("2-year") cladodes as food for the colony. These are dark green and no thicker than -2 cm. The younger cladodes are thin and light green and a few 97 MARTI et al.: Rearing Cactob/astiS cactorum of these are collected to feed newly-hatched larvae. Cladodes are grasped with tongs, removed with a knife or pruning tool, and placed in a plastic tub for transport to the laboratory, where they may be stored up to several weeks in a cold room at 12 C. Remove spines from cladodes using scissors, heavy forceps, a scraper, or knife. Wash by soaking in cool or cold tap water with detergent, and scrub with a brush to remove all traces of dirt, rinse, then set them on the counter to dry. Avoid washing cladodes in hot water, as this may cook them. Cut large cladodes into two smaller pieces (-10 x 20 cm) and store them in the cold room until needed. Store young cladodes for neonates intact in a separate container in the cold room and cut them just before use. When eggs darken, place an eggstick with no more than -100 eggs into a 30-ml plastic cup with a 2 x 2 cm piece of young cladode so that food is immediately available to the neonates upon hatching. C. cactorum neonates will die within several hours if food is not available, but they may be held for several days in the cups as long as they have not completely consumed their food. We have recently begun placing only 1 eggstick per cup. In the event that disease problems arise later, the larvae from the entire container are discarded and the loss is limited to larvae developing from a single eggstick. Each container is provided with a 10 x 27 cm grid, made from hardware cloth, in which 2 cm at each of the long ends has been bent at right angles. This grid is used to support the cladode(s). Approximately 150 mL of a mixture of cat litter and sand is added to the bottom of the container to soak up excess moisture dripping from the cladode as the larvae develop. When containers have been prepared and neonates are ready, place a 2 x 2 cm piece of cladode containing approx. 70-100 C. cactorUm neonates on top of the cladode, secure the lid, label the container, and place the container in a chamber or incubator room at 26 C, 12:12 In photoperiod, and 70% or higher relative humidity (Fig. 1). Check the containers 10-14 d after inoculation and at least once weekly thereafter. Place a fresh cladode under the old one if larvae are still feeding inside it. As the old cladode is consumed, the larvae migrate to the fresh one and begin feeding. The larvae feed on the interior contents of the cladodes and do not consume the large fibers or the exterior cuticle. The remains of old cladodes should be checked for the presence of larvae and cocoons and discarded if none are present. Return any larvae to the container and remove and incubate the cocoons. Discard excess frass, silk, and dead larvae. From this point, the collection and management of cocoons and management of adults from cladode-reared larvae is identical to that of the diet- reared larvae. C. cactorum artificial diet is Rearing Cactoblastis cactorum on artificial diet. made from commercially available components. Because there are several suitable sources for the diet components, we list here only the components and not the sources. The diet consists of the following: water (2.5 L), agar (45 g), mold inhibitor (15 ml of a solution consisting of propionic , 418 ml; phosphoric acid, 42 ml; and water 540 ml), sucrose (100 g), cholesterol (3.2 g dissolved in 15 ml liquid soy lecithin just before use), ascorbic acid (9.6 g), potassium sorbate (4.2 g), white kidney beans (630 g, ground in a hammer mill with a 0.238 cm screen), Brewers yeast (186 g), malic acid anhydrous (15 g), citric acid anhydrous (5 g), and oxalic acid dihydrate (5 g). All of the diet components, except water and the soy lecithin, are dry and can be weighed in advance on a balance and stored in individual containers in the laboratory Iq

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Fig. 1. A 21 x 30 x 8 cm plastic container with one mature Opuntia cladode is shown supported on a grid and inoculated with several 2 x 2 cm squares of young cladode upon which Cactoblastis cactorum neonates have fed for several days. A mixture of cat litter and sand is spread on the bottom for moisture control. Several plastic cups containing additional squares of young cladodes with neonates await placement in containers.

or used immediately. If extensive mold growth is observed on frass, methyl paraben (6 g) may be optionally added to the above as an additional mold inhibitor. Autoclave three 1-L flasks of tap water for 10.5 min at 124.2 kPa in the chamber and jacket, at a temperature of 250 C. While the water is being autoclaved, add the cholesterol to the lecithin in a 30-ml plastic cup or small beaker and allow it to dissolve. Stir any undissolved cholesterol into the lecithin before adding the mixture to the blender. Any commercial 4 L blender is satisfactory. After the water has been autoclaved, measure 2.5 L with a graduated cylinder and pour it into the blender. Add the agar first and stir it into the hot water, then add the other ingredients with the ground kidney beans added last. Stir the mixture with a spatula, then blend for 1 min with the lid in place. Cover a 28 x 43 cm cookie tray with aluminum foil and pour the mixture into it to a depth of about 2 cm and allow it to cool and harden for several hours. Turn the hardened sheet of diet over onto a towel MARTI et al.: Rearing Cactob/astis cactorum 99 spread on a laboratory counter and allow additional time for excess moisture to evaporate from the newly-exposed surface. Cut the diet into 4 x 4 x 2 cm individual squares with a knife or cookie cutter. To cover the diet squares with wax, grasp each square of diet on one side and dip for 1-2 sec into molten beeswax at 250 C. The wax hardens quickly and the process is repeated by holding the square on the other side and dipping it into the wax again so that each square of diet is completely coated with wax. Store the coated diet in plastic containers at room temperature until needed but do not refrigerate or the wax will become brittle. Avoid beeswax with pesticide resi- due, as this may kill neonates. The larvae do not consume the wax. Its presence helps delay desiccation of the diet and provides protection for the larvae as a simulated cactus cladode. The pH of the diet is 4.1 and can be adjusted by altering the proportions of the organic acid components (Fig. 2). When containers and diet have been prepared and eggs have begun to darken, place one square of diet into each container and place a single eggstick directly on top of the diet, secure the lid, label and date the containers, and place them in a chamber or incubator room at 260, 12:12 In photoperiod, and 70% or higher relative humidity. The larvae hatch and chew a small hole through the wax coating of the diet square and begin feeding. Alternatively, a small hole may be punched through the wax and the eggstick inserted a few millimeters. This method provides the larvae with a pre- existing entry point to the diet. The larvae generally leave and enter the diet square en masse and deposit most of their frass outside the diet square. No support grid or cat litter are required in containers in which C. cactorum larvae are reared on artificial diet. A grid and/or cat litter is needed only for cladode-reared larvae because of the high water content of cladodes (Fig. 3). The larval rearing containers should be checked 10-14 d after eggs hatch and once weekly thereafter. Place a fresh diet square adjacent to the old one before it is completely consumed. As the old diet is consumed, the larvae migrate to the new one and begin feeding. Check old diet squares and discard them if no larvae and cocoons are present. Return any larvae to the container and remove and incubate the co- coons. Excess frass, silk, and dead larvae should be discarded. As the larvae grow, they consume their food more quickly than when they were small. Care must be taken to ensure that food is constantly available, otherwise small larvae die in 1-3 d and larger larvae produce abnormally small pupae. Check containers before an approach- ing weekend or holiday. Label containers so that they can be checked at the proper dates (Fig. 4). From this point, the management of diet-reared larvae is identical to that of the cladode-reared larvae. Procedures common to both rearing methods. At an incubation temperature of C. cactorum 26 C, C. cactorum larvae require about 30 d to reach the pupal stage. larvae are gregarious and prefer to feed together in large numbers. Cannibalism is not known to be a problem with this species, but overcrowding should be avoided. Larval growth and survival have been found to be satisfactory with approx. 70-85 larvae per container for cladode rearing, though this may differ according to diet and container size. A 0.5 I container with artificial diet can support about 75-100 larvae and larger containers can support proportionately more. Smaller containers are preferable be- cause fewer larvae are lost if the whole container is discarded due to disease. After feeding for 30 or more days, larvae evacuate their gut contents, spin a cocoon, and molt to the pupal stage. Usually the larvae leave the food source and climb to the top edge of the container or to the lid. If large numbers of larvae are present in a container, some will spin cocoons near the food source or in the frass and

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Fig. 2. After diet has hardened in the cookie tray, it is turned over onto a towel on the - counter and allowed additional time to dry and then cut into squares with a large knife. Squares are dipped into molten beeswax to give them a thin protective coating.

silk at the edges and bottom of the container. Containers need to be checked for cocoons before the container is emptied and cleaned for the next cycle of larvae. Cocoons of the same age are gathered by hand from the larval rearing containers, placed into separate containers, and incubated at 26 C to allow the adults to emerge. Because larvae of the same age pupate over a period of several days or a week, several collections are needed to gather them all. Pupae may be left in the cocoons to allow the adults to emerge on their own or may be extracted manually from the

I r MARTI et al.: Rearing Cactoblastis cactorum 101

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Fig. 3. A 19 x 29 x 9 cm container with fresh diet and a piece of older diet upon which larvae (not visible) are feeding. Diet can be formed into any convenient shape.

cocoons. For manual extraction, the pupa should first be allowed to harden for several days. Each cocoon is then picked up and a small tear or cut made in the silk at the wider anterior end. The pupa is pushed from the opposite end of the cocoon through the hole. Pupae freed from cocoons may be sexed and sorted by gender. Optionally, pupae may be removed from cocoons by using 6% sodium hypochlo- rite to dissolve the silk. A group of about 30 cocoons are placed into a small sieve and dipped into the sodium hypochlorite for no more than 18 sec. This is an exothermic reaction producing much heat and foam. The pupae must be rinsed vigorously in running tap water for 2 min then placed on paper towels to dry. Lack of care with this technique will result in death of the pupae. Several hundred pupae of the same age and approximately equal numbers of each gender are placed into a shallow dish or Petri dish lid in a mating cage. Alter- natively, for research purposes or disease control, individual pairs may be mated separately in containers as small as a 30-ml plastic cup provided with a ventilated lid and a small piece of cactus. For mass rearing, however, larger mating cages are used. These are transparent polycarbonate plastic containers such as Rubbermaid® type 6,308 or 6,318, which are 20 x 20 x 18 cm and 26 x 28 x 30 cm, respectively. A 9-cm hole suitable for manual access is cut into one side of the cage and stocking cloth is glued to the edge of the hole. One side can be cut out and screen glued in place to provide ventilation. The lid serves as the bottom. The presence of large

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Fig. 4. Small 400 ml circular plastic containers with large Cactoblastis cactorum larvae visible on artificial diet.

numbers of moths releases scales into the air. These must be controlled with a suitable air handling system with filters and employees should be provided with face masks and goggles if requested (Fig. 5). Large 1 x 1 x 1 m screen cages, provided with a piece of cactus, and containing up to 2000 cocoons, estimated by weight, may also be used for adult emergence. Smaller cages should be used for proportionately fewer cocoons. Adults usually mate 1 d after emerging and may mate several times. Females lay 1-4 eggsticks and these may be placed anywhere within the cage. Eggsticks should be gathered daily and incubated by age groups in labeled containers. Although adults may live up to 2 wks, females are no longer productive after 5-7 d of age. Adults have vestigial mouthparts and do not feed, but require a cage temperature of 25-30 C and relative humidity of 70% or higher. We use a 12:12 h photoperiod, although other light regimens are also satisfactory. C. cactorum females lay their eggs in long columns or stacks known as eggsticks. These contain 20-100 or more individual eggs. Eggsticks resemble cactus spines and can be collected from established C. cactorum colonies or in the wild from Opuntia cladodes in regions of the world where C. cactorum is common (e.g., Argentina, Islands, , , and the Gulf Coast of the US). If C. cactorum adults are available, they can be placed together in mating cages. Females usually begin to lay eggsticks on the second day after mating. Eggsticks of the same approximate age and source are gathered from the substrate to which they are attached and stored in convenient labeled containers until they are within a few days of hatching. Optionally, eggs may be counted under a stereoscopic microscope to place a specific number on the food source (Fig. 6). C. cactorum eggs require about 24-30 d incubation at 26 C. Slightly cooler or MARTI et al.: Rearing Cactob/astis cactorum 103

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Fig. 5. Mating cage with cactus cladode and Cactoblastis cactorum pupae

warmer incubation temperatures may be used, but we find that incubation at 26 C is satisfactory. An environmental chamber or rearing room on a 12:12 h photoperiod and a relative humidity of 70% or higher is used. A relative humidity near 100% is pref- erable, but in practice this is often difficult to maintain. As individual eggs mature, they darken several days before hatching and the eggsticks should then be placed on the food source. Avoid exposing eggsticks to temperature extremes. We have encountered major problems with viral and microsporidian diseases in larvae reared on artificial diet, particularly in earlier versions of the diet. The cladode- reared colony has been relatively free of viral disease, perhaps because of protection conferred by the natural food. Larvae can be checked for the presence of microspo- ridian spores on a compound microscope, but suspected viral disease must be con- firmed by electron microscopy (Marti et al. 2007). Discard all larvae from a container if any are found positive for disease. Once a colony is infected with microsporidia, eradication can be difficult. Strict attention to cleanliness is essential. Containers with larvae dying from microsporidian infection have a characteristic odor. Antibiotics such as Fumagilin-BTM may be used to treat eggsticks for spores adhering to the external surface, but its effectiveness is not established in the case of C. cactorum.

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Fig. 6. Cactoblastis cactorum eggsticks on an Opuntia cladode

Microsporidia can be transmitted transovarially as well as through ingestion of infective spores. Uninfected larvae can be obtained after one or more generations by pairing adults in small containers and then examining them for spores after the female has ceased producing eggsticks. If either adult is positive, the eggs are discarded or used for research but not added to the colony. After all cocoons have been collected from a container, the remaining diet or cladode and cat litter are discarded and the grid and containers are scrubbed with a brush in hot water containing CloroxTM. Lids should be washed separately in cool water to avoid loosening the glue that secures the mesh ventilation. Gloves should be worn at all times and changed between servicing of containers. Containers of a variety of shapes and sizes are suitable for rearing C. cactorum larvae. They should, however, be transparent or translucent, have tightly fitting lids, and ventilation holes. C. cactorum larvae at CPMRU are reared to the pupal stage in Rubbermaid "Servin SaverTM 4.0 L (#7) translucent rectangular containers with lids. These are 19 x 29 x 9 cm and have a tightly-fitting lid to prevent escape of larvae. Two 6.5 cm ventilation holes are cut into the lid with a drill press. The cut surface of each hole is smoothed with a deburring tool and the perimeter on the underside of the lid is roughened to a width of -1 cm with sandpaper. The holes are covered on the underside with a fine mesh sheer curtain cloth, optionally supported by screen wire, and sealed in place with hot glue.

Results and Discussion

Survival of C. cactorum, particularly in a research facility in which diet development is an ongoing process, has been variable, with extremes of 0-100% sometimes en- countered in individual containers. Disease, inadequate diet, and unexplained factors all contribute to reduce the number of viable adults obtained from an eggstick con- taining an average of 75 eggs. Of these eggs, 99% hatch, but 50% of the larvae are 105 MARTI et al.: Rearing CactoblastiS cactorum generally lost, and another 10% are lost as pupae, with fewer than 1% lost as ab- normal adults, leaving about 33 adults as survivors. Outbreaks of virus have been sporadic in the diet-reared colony but rare in the cladode-reared colony. Microsporidia are present in both colonies. The current diet formula, rearing methods and diet presentation procedures have mitigated the disease problems associated with the diet-reared colony, resulting in a survival rate that is roughly comparable to the clad- ode-reared colony. However, the cost and space requirements for each are different. Insect rearing costs include labor, overhead, materials and equipment, and the diet itself. Calculations based only on cost and weight of the ingredients of C. cactorum artificial diet show that 4 diet cakes of 75 g each (300 g total) are required to produce 33 C. cactorum adults from an initial inoculation of 1 eggstick containing approxi- mately 75 eggs and that each diet cake costs 0.5 cent, or 2 cents total. This amounts to an estimated cost of $1 per 1650 adults, but does not include costs for labor, materials other than diet, facilities and utilities, or overhead. This ratio can improve to the extent that diet costs decrease and future developments in diet composition, rearing techniques, and disease control reduce attrition and increase the percentage of eggs that survive to the adult stage. colony, approximately half of the immature In the cladode-reared C. cactorum stages are lost to attrition, a figure similar to that experienced in the diet-reared colony. During the time required to rear 33 adults from 75 eggs, a total of 4 half- cladodes (approximately 650 g) are consumed or cladodes, or 2 full 0. ficus-indiCa destroyed. Because the cladodes are collected gratis from the wild, there is no in- trinsic purchase cost involved in collecting them (discounting fuel) except for the cost of labor, which was estimated to be $10 per hour. We therefore used the labor cost in collecting of cladodes as a means of comparison with the cost of the ingredients in the diet-reared colony. It was estimated that 1 h, or $10, was required to collect sufficient cladodes to supply 25 rearing containers with cladodeS for 1 complete rearing cycle. Based on 33 adults reared from each of these 25 containers, the $10 cost to rear 825 adults converts to an estimated $1 per 82.5 adults, a considerably lower return compared with rearing on diet. We have not tried to factor in other costs, or to determine the extent of which are considerable, in the rearing of C. cactorum, shared costs. These other costs include all labor involved in the rearing process after bringing the cladodes to the laboratory, facilities and utilities, overhead, and purchase C. of materials and equipment. Many of these other costs are also incurred in rearing cactorum on diet. These other expenses greatly increase the true rearing costs above that of the diet or of cladode collection. Most of the insects Space considerations are also a factor in rearing C. cactorum. in the diet-reared colony are maintained in a room 5.49 x 4.12 m, or 22.62 m2, containing 6 steel racks with 8 shelves each. Shelves are 60 x 175 cm and provide space for 75 round plastic containers (12 cm diameter) per shelf. These 6 racks, if filled with rearing containers, hold 75 x 8 x 6 = 3,600 containers. Based on the previous estimate of 33 adults per container, approximately 118,800 adults could be produced every 2 months from this room, or about 5,252 adults per square meter of floor space in the same period. Production could be increased with additional racks or by increasing the productivity per container to more than 33 adults from 75 eggs, or by improvements in diet or management techniques that would permit an initial in- oculation of more than 75 eggs. C. cactorum are maintained in several different rooms, the one Cladode-reared . The insect most similar to the diet-reared colony measuring 5.5927.8 x m4.982 m, or 106 J. Entomol. Sci. Vol. 43, No. 1 (2008)

containers in the cladode-reared colony are rectangular, with dimensions of 20.3 x 30.5 cm, although containers of other sizes have been used in the past. This room contains 10 racks of 8 shelves each, with 16 containers per shelf, for a total of 1280 containers. Based on the estimate of 33 adults from each container, this room pro- duces 42,240 adults every two months, or about 1519 adults per square meter of floor space every two months, considerably fewer that the diet-based production, and at greater cost. Our long-term objective is not to continually produce C. cactorum with Opuntia cladodes as the food source. Cost and labor considerations favor rearing this species on artificial diet unless specific research, such as food preference trials, require the use of Opuntia. C. cactorum as an emergent threat requires, however, that the initial rearing of this species take place on cladodes while the artificial diet undergoes development to a point at which management can confidently replace the former with the latter in a mass-rearing facility for this species.

Acknowledgments

The authors gratefully acknowledge the valuable technical assistance of Susan Drawdy, who was largely responsible for development of procedures for rearing C. cactorum on cladodes and for management of that colony, and Robert Caldwell, who constructed large numbers of a variety of different containers for use in rearing of larvae and as mating cages for adults. References Cited

Carpenter, J. E., K. A. Bloem and S. Bloem. 2001. Applications of Fl sterility for research and management of Cactoblastis cactorum (Lepidoptera: Pyralidae). Fla. Entomol. 84: 531-539. Habeck, D. H. and F. D. Bennett. 1990. Cactoblastis cactorum Berg (Lepidoptera: Pyralidae), a Phycitine new to Florida. Florida Dept. Agric. Cons. Serv. Div. of P1. Indust. Circ. No. 333. Marti, 0. G., E. L. Styer, R. E. Myers and J. E. Carpenter. 2007. Viruses in laboratory-reared cactus moth, Cactoblastis cactorum (Lepidoptera: Pyralidae). Fla. Entomol. 90: 274-277. Perez-Sandi, C. M. 2001. Addressing the threat of Cactob/astis cactorum (Lepidoptera: Pyrali- dae), to Opuntia in Mexico. Fla. Entomol. 84: 499-502. Solis, M. A., S. D. Hight and D. R. Gordon. 2004. Tracking the cactus moth, Cactoblastjs cactorum Berg., as it flies and eats its way westward in the U.S. News Lepidopt. Soc. 46: 3-7. Stiling, P. and D. C. Moon. 2001. Protecting rare Florida cacti from attack by the exotic cactus moth, Cactoblastis cactorum (Lepidoptera: Pyralidae). Fla. Entomol. 84: 506-512. Vigueras G., A. L. and L. Portillo. 2001. Uses of Opuntia species and the potential impact of Cactoblast,s cactorum (Lepidoptera: Pyraiidae) in Mexico. Fla. Entomol. 84: 493-498. Zimmerman, H. G., V. C. Moran and J. H. Hoffmann. 2001. The renowned cactus moth, Cactoblastis cactorum (Lepidoptera: Pyralidae): its natural history and threat to native Opun- tia floras in Mexico and the United States of America. Fla. Entomol. 84: 543-551.