Since its debut in 1982, The Land has embodied Walt Disney's vision, capturing the attention of millions of EPCOT guests with venues focusing on agriculture and environmental stewardship and sustainability. The Land pavilion spans more than 8 acres in the World Nature section of EPCOT at the Walt Disney World Resort in Lake Buena Vista, Florida. The pavilion houses three attractions, namely Soarin' Around the World, Awesome Planet, and the Living with the Land boat ride, complemented by a greenhouse walking tour entitled Behind the Seeds and two restaurants. Each attraction derives inspiration from nature and challenges mankind to be responsible stewards of planet earth. This feature article focuses on the Living with the Land boat ride attraction, which traverses greenhouses showcasing agricultural technologies and crops from around the world. The sections below describe both how various show elements are designed to engage guests and how the show is made possible by applying relevant science and technology.
The sweetpotato whitefly, Bemisia tabaci MEAM1, is one of the most devastating pests of row-crop vegetables worldwide, damaging crops directly through feeding and indirectly through the transmission of many different viruses, including the geminivirus Tomato yellow leaf curl virus (TYLCV). Y-tube olfactometer tests were conducted at different stages of TYLCV infection in tomatoes to understand how TYLCV affects B. tabaci behavior. We also recorded changes in tomato hosts’ color and volatile profiles using color spectrophotometry and gas chromatography-mass spectrometry (GC-MS). We found that the infection status of B. tabaci and the infection stage of TYLCV influenced host selection, with uninfected whiteflies showing a preference for TYLCV-infected hosts, especially during the late stages of infection. Viruliferous B. tabaci attraction to visual targets significantly differed from non-viruliferous B. tabaci. Late-stage infected hosts had larger surface areas reflecting yellow-green wavelengths and higher emissions of methyl salicylate in their volatile profiles. These findings shed new light on several critical mechanisms involved in the viral manipulation of an insect vector and its economically important host.
The addition of non-crop floral resources is known to improve the fitness of many beneficial arthropods. Orius insidiosus (Say; Heteroptera: Anthocoridae) is a predator of several economically important pests and is known to feed on pollen. Spanish needles, Bidens alba L., and Leavenworth's tickseed, Coreopsis leavenworthii Torrey & Gray (both Asteraceae), are two Florida native wildflowers that may serve as sources of pollen beneficial to O. insidiosus. The current study investigated the effects of adding flowers from C. leavenworthii and B. alba to the diet of captive O. insidiosus on longevity, nymphal development time, and cannibalism. A mixed diet of flowers and thrips prey increased O. insidiosus adult female longevity. Nymphal development time was reduced when B. alba was added to thrips when compared to a diet of thrips alone. Interestingly, cannibalism was low in all instances, suggesting a negligible effect of cannibalism on O. insidiosus except perhaps in extreme situations. These results indicate that B. alba and C. leavenworthii flowers can increase longevity and fitness of O. insidiosus, thus providing support for the use of these plants to enhance natural enemy services.
Insect-vectored plant pathogens are known to alter host-plant quality and associated cues, subsequently affecting the frequency of interactions with vectors and influencing pathogen transmission. It is unknown whether these changes deliver information highly specific to the vector and have evolved as a result of host manipulation or if they are more generalist indicator of plant status. In the current study, the responses of two thrips species, Frankliniella occidentalis Pergande, the vector of the tospovirus Tomato spotted wilt virus (TSWV) and a non-vectoring species, F. tritici Fitch, to pathogen-induced plant volatiles (PIPVs) in tomatoes were investigated. As the two species cohabit, and one is a vector of tospoviruses while the other is not, this system is perfectly suited to investigate the specificity of PIPVs to insect vectors. Both species were exposed to PIPVs of TSWV and the begomovirus Tomato yellow leaf curl virus (TYLCV) transmitted by the sweet potato whitefly, Bemisia tabaci Gennadius. Frankliniella tritici did not respond to PIPVs. F. occidentalis was attracted to both TSWV- and TYLCV-infected plants and showed no preference between plants infected by either virus. Volatiles from TSWV- and TYLCV-infected plants were collected and identified using GC–MS. Principal component analysis showed a clear differentiation between the volatiles of the uninfected and infected tomatoes. There was no differentiation between the volatile profiles of the two virus-infected tomatoes, suggesting that PIPVs may be a by-product of viral infection that elicit a generalist response in F. occidentalis and are likely not the result of host manipulation.
Frankliniella flower thrips are pests of numerous fruit and vegetable crops as they feed and reproduce in the flowers and fruits. The invasive Frankliniella occidentalis (Pergande) from the Southwestern United States, an economic pest in Florida since 2005, and the native Frankliniella bispinosa Morgan are both found in Florida strawberries. The objective of this research was to characterize injury to strawberry fruit from these species. Densities of 0, 2, 4, 8, 16, or 32 adult females of each species were caged on a strawberry plant with one flower. The cages were removed after 2, 5, or 10 d, and the number of surviving adults and the number of larvae determined. Injury was quantified on the mature fruit 21 d after thrips were introduced onto the experimental plant. Initial densities as low as two adult F. occidentalis females per flower decreased fruit set and increased cat-facing on the fruits that developed. There were no significant effects on fruit set and cat-facing by any initial density of F. bispinosa. Feeding by thrips on the small, green fruit affected the size and shape of the mature fruit: the diameters were decreased as a linear function of increased feeding by F. bispinosa, and the weights were decreased as a linear function of increased feeding by F. occidentalis. Overall, results showed that F. occidentalis was more damaging to strawberry than F. bispinosa. The differences in pest status between these common flower thrips species in Florida presents challenges to management programs.
Frankliniella invasor is an important pest of mango in Central America; however, information is limited concerning the activity of insecticides with different modes of action. Eight insecticides representing 5 different chemical classes were assayed for control of F. invasor in Costa Rica. The spinosyns, spinetoram, and spinosad were highly active, whereas malathion and alpha-cypermethrin were the least active. The neonicotinoids imidacloprid and thiamethoxam resulted in intermediate toxicity to this thrips pest.
The western flower thrips, Frankliniella occidentalis (Pergande), is a polyphagous pest that has been spread worldwide. The extensive use of insecticides in attempts to control its populations eliminates natural enemies and competitor flower thrips species, thereby increasing its populations. An unsustainable situation develops with concomitant resistant pest populations, secondary pest outbreaks, and environmental degradation. Integrated pest management utilizes knowledge of pest and natural enemy relationships to implement tactics that are environmentally friendly and sustainable. Minute pirate bugs are the most important worldwide predators of thrips. They can suppress and ultimately control Frankliniella species flower thrips. Flower samples taken at least weekly are needed to understand predator-prey dynamics. Shown here is the sampling of the flowers of fruiting vegetables and companion plants to estimate the densities of individual thrips and minute pirate bug species. Representative data illustrates how the protocol is used to determine the efficacy of management tactics over time and how to evaluate the benefits of predation by minute pirate bugs. The sampling protocol is similarly adaptable to sampling thrips and minute pirate bugs in other plant species hosts.
Cassava and cacao are 2 of the most important crops grown in Costa Rica, and also are major sources of income for rural farmers. These crops are frequently attacked by Corynothrips stenopterus Williams and redbanded thrips, Selenothrips rubrocinctus Giard (Thysanoptera: Thripidae). Most farmers who grow these crops apply synthetic insecticides on a calendar basis, but there are no well-established studies on the effectiveness or toxicity of different chemical insecticides on these species of thrips. The objective of this study was to determine the toxicity of 8 insecticides with different modes of action that are used in the control of other thrips species. Commercial formulations of chlorfenapyr, imidacloprid, chlorpyrifos, spinosad, malathion, thiamethoxam, spinetoram, and a-cypermethrin were evaluated on adults of both thrips species under laboratory conditions. Probit analyses showed that spinetoram, spinosad, and chlorfenapyr were the most effective against both thrips species, with median lethal dosages of 50% below 1 mu g per mL for both species: 0.12, 0.08, and 0.21 mu g per ml for C. stenopterus, and 6 x 10(-3), 0.06, and 0.53 mu g per ml for S. rubrocinctus. For the other 5 insecticides tested, C. stenopterus had a higher susceptibility than S. rubrocinctus. Among all the insecticides tested, malathion was the least efficacious against both thrips species. The mortality rate in the control treatments never exceeded 10%. The results of this study suggest that spinetoram, spinosad, and chlorfenapyr are the most efficacious insecticides for the control of both thrips species. These results should be complemented with field trials for confirmation.