First-instar Nymphs Research Articles

Sublethal effects of a pyrethroid insecticide on cuticle thickness, wing size and shape in the main vector Triatoma infestans.

Exposure to sublethal doses of insecticide may affect biological traits in triatomines. We investigated the effects of toxicological phenotype (pyrethroid resistance status) and exposure to sublethal doses of deltamethrin on two traits of Triatoma infestans Klug (Heteroptera: Reduviidae) using a phenotypic plasticity experimental design. First-instar nymphs from 14 and 10 full-sib families from pyrethroid-susceptible and pyrethroid-resistant populations, respectively, were used. For the susceptible population, we treated first instars topically with acetone (control) or deltamethrin (treatment) once. For the resistant population, instars were treated once, twice and three times as first, third or fifth-instar nymphs, respectively. We measured cuticle thickness, wing size and wing shape of 484 emerging adults, and tested for treatment effects using mixed ANOVA and MANOVA models. Toxicological phenotype, exposure to deltamethrin and full-sib family exerted significant effects on cuticle thickness, wing size and wing shape. Adult triatomines previously treated with deltamethrin developed significantly thicker cuticles than control triatomines only in the resistant population and significantly bigger wings in both populations. Mean cuticle thickness and wing size increased with increasing exposures to deltamethrin. Exposure to sublethal doses of deltamethrin generated morphological modifications that may affect insect survival and flight dispersal, and hence may have evolutionary and epidemiological consequences.

Taxonomic notes on the genus Cyphococcus Laing (Hemiptera: Coccomorpha: Coccidae), with description of a new species from India.

The adult female, first-instar nymph, male pupa and adult male of a new species of the genus Cyphococcus Laing (Hemiptera: Coccomorpha: Coccidae) from India, C. williamsi Joshi Rajgopal sp. n., are described and illustrated. This is the first record of the genus Cyphococcus and the subfamily Cyphococcinae from the Oriental region. Information on distribution, biology, host plants, associated coccinellid predators and hymenopteran parasitoids is given.

Taxonomic and identification review of adventive Fiorinia Targioni Tozzetti (Hemiptera, Coccomorpha, Diaspididae) of the United States.

This work provides general descriptions, illustrations, molecular diagnostic data, taxonomic keys, slide mounting recommendations, and Florida distribution records for Fiorinia Targioni Tozzetti species occurring in the USA. Species treated are F.externa Ferris, F.fioriniae (Targioni Tozzetti), F.japonica Kuwana, F.pinicola Maskell, F.phantasma Cockerell & Robinson, F.proboscidaria Green, and F.theae Green. New descriptions of second-instar males and females of all seven species in addition to first-instar nymphs and adult females of F.phantasma and F.proboscidaria are presented. Taxonomic keys to second-instar males and females are developed for the first time and previously available taxonomic keys to first-instar nymphs and adult females are improved. DNA sequences were used to further evaluate the monophyly of Fiorinia and provide additional diagnostic tools for Fiorinia species. Multigene phylogenetic analyses, COI barcoding methods, and examination of type material indicate that F.yongxingensis Liu, Cai & Feng, 2020, syn. nov. is a junior synonym of F.phantasma. A morphological survey of the genus demonstrates, for the first time, the utility of second-instar males for diagnostics. This study will help inform regulatory and pest management decisions by facilitating morphological and molecular identification of adventive Fiorinia species occurring in the USA.

Exposure Route Affects the Toxicity Class of Thiamethoxam for the Predatory Bug, Orius albidipennis (Hemiptera: Anthocoridae) by Changing Its Fitness.

In many cases, pesticides' side effects on natural enemies have closely related to their exposure route. We assessed long-term lethal and sublethal effects of thiamethoxam (TMX) on the predatory bug, Orius albidipennis (Reuter), fed on Aphis gossypii Glover (Hemiptera: Aphididae), through three exposure routes. First-instar nymphs were treated with the maximum field recommended concentration (MFRC), ½ MFRC, and ¼ MFRC of TMX for 24 h. Based on the results, the soil-application treatment (bottom-up effect: plant-aphid-predator) led to the lowest survival reduction. In contrast, leaf-dip (residual contact) and aphid-dip (oral exposure route) treatments decreased the survival severely. While the soil-application treatment had no significant effect on adult longevity and egg production, all tested concentrations of TMX in the leaf-dip and aphid-dip treatments negatively affected both traits. The egg hatchability was not affected by the insecticide in all exposure routes. Among all treatments, ¼ MFRC of TMX in the residual contact and oral treatments shortened the egg incubation period compared to control, but others failed to affect it. Finally, based on the criteria provided by the International Organization for Biological and Integrated Control (IOBC) regarding toxicity classification, systemic (soil) application of TMX was harmless for this predator. However, it was moderately harmful and harmful (depending on concentration) to the predator through the residual contact and oral exposures, even at ¼ MFRC. Given our results, the soil-application of TMX is compatible with O. albidipennis, and it can improve conservation approaches of the predator in the integrated management of A. gossypii.

Effectiveness of orally-delivered double-stranded RNA on gene silencing in the stinkbug Plautia stali.

Development of a reliable method for RNA interference (RNAi) by orally-delivered double-stranded RNA (dsRNA) is potentially promising for crop protection. Considering that RNAi efficiency considerably varies among different insect species, it is important to seek for the practical conditions under which dsRNA-mediated RNAi effectively works against each pest insect. Here we investigated RNAi efficiency in the brown-winged green stinkbug Plautia stali, which is notorious for infesting various fruits and crop plants. Microinjection of dsRNA into P. stali revealed high RNAi efficiency-injection of only 30 ng dsRNA into last-instar nymphs was sufficient to knockdown target genes as manifested by their phenotypes, and injection of 300 ng dsRNA suppressed the gene expression levels by 80% to 99.9%. Knockdown experiments by dsRNA injection showed that multicopper oxidase 2 (MCO2), vacuolar ATPase (vATPase), inhibitor of apoptosis (IAP), and vacuolar-sorting protein Snf7 are essential for survival of P. stali, as has been demonstrated in other insects. By contrast, P. stali exhibited very low RNAi efficiency when dsRNA was orally administered. When 1000 ng/μL of dsRNA solution was orally provided to first-instar nymphs, no obvious phenotypes were observed. Consistent with this, RT-qPCR showed that the gene expression levels were not affected. A higher concentration of dsRNA (5000 ng/μL) induced mortality in some cohorts, and the gene expression levels were reduced to nearly 50%. Simultaneous oral administration of dsRNA against potential RNAi blocker genes did not improve the RNAi efficiency of the target genes. In conclusion, P. stali shows high sensitivity to RNAi with injected dsRNA but, unlike the allied pest stinkbugs Halyomorpha halys and Nezara viridula, very low sensitivity to RNAi with orally-delivered dsRNA, which highlights the varied sensitivity to RNAi across different species and limits the applicability of the molecular tool for controlling this specific insect pest.

Biological, epidemiological and population structure analyses of vitiviruses in Iran

The presence of three vitiviruses associated with grapevine rugose wood disease, i.e. grapevine virus B (GVB), grapevine virus E (GVE) and grapevine virus F (GVF), was studied in 650 grapevine samples collected from eight viticulture growing provinces of Iran. RT-PCR assays conducted on these samples showed that 69.5% of the grapevine material is infected at least with one virus; of which GVE was the prevailing virus (29.5%), followed by GVF (23.6%) and GVB (16.4%). The genetic variability and population structures of vitiviruses found in Iran were thoroughly analyzed by sequencing the complete coat protein gene of 29 isolates from different regions. BLAST analysis disclosed 81–96%, 77–80% and 87–96% identities at the nucleotide level and 91–98%, 80–85% and 93–97% identities at the amino acid level between Iranian GVB, GVE and GVF, respectively; and their corresponding reference isolates from the GenBank. The phylogenetic analyses showed two divergent evolutionary lineages for each vitivirus species that were related to the geographic origin of isolates. The high FST values found among GVE and GVF populations indicated that both viruses are under different evolutionary constraints in Iran, suggesting more than one origin. The neutrality analysis also suggested that GVE and GVF in Iran and in the world were inferred from the old presence of GVB, through gene flow and positive selection pressures that shaped the genetic structure of vitiviruses populations. The transmission trial conducted with Planococcus ficus under controlled conditions showed that GVE can be transmitted by the first-instar nymphs.

Description of a new species of Kermicus Newstead (Hemiptera: Coccomorpha: Pseudococcidae) from bamboo in southeast China.

A new species, Kermicus huizhouensis Wu Huang sp. n. (Hemiptera: Coccomorpha: Pseudococcidae), is described and illustrated based on the adult female, second instar female and first-instar nymph. It was collected at Qianfeng village, Huiyang District, Huizhou City, Guangdong Province, P. R. China, inside the stem of bamboo Bambusa rigida (Poaceae) and attended by the ant Tetraponera binghami (Forel) (Hymenoptera: Formicidae). It differs from K. wroughtoni Newstead, 1897 by the adult female lacking multilocular disc pores in the marginal region of the venter, and both the adult female and first-instar nymph having the anal ring bearing 16-20 setae. Keys to genera of legless mealybugs on bamboo based on adult females, and the immature stages of Kermicus, are provided.

Water Loss and Desiccation Tolerance of the Two Yearly Generations of Adult and Nymphal Kudzu Bugs, Megacopta cribraria (Hemiptera: Plataspidae).

Water loss rate, percentage total body water content (%TBW), cuticular permeability (CP), and desiccation tolerance were investigated in adult and immature stages of the invasive kudzu bug, Megacopta cribraria (Fab.) (Hemiptera: Plataspidae), a serious soybean pest and an urban nuisance. Adults and all five nymphal instars were weighed prior to and 2, 4, 6, 8, 10, and 24 h after desiccated at 30 ± 1°C and 0-2% RH. Both % initial mass and %TBW loss increased linearly with time of desiccation. Rates of loss ranged from approximately 1-7%/h. Mortality occurred at 10 h after desiccation. Desiccation tolerance (%TBW lost at death) ranged between 25.6% for first-generation adult females and 75% for first-generation fifth-instar nymphs. First-generation first-instar nymphs had significantly greater %TBW (88.9%) than the other generations and instars, whereas second-generation fifth instars had the lowest %TBW (62.4%). The CP value of first-generation adult females (12.3 ± 1.6 µg cm-1 h-1 mmHg-1) was the greatest across generations. First-generation first instars had the greatest mass loss (111.11 mg/g) among all instars and generations, whereas overwintered second-generation adult females had the lowest mass loss (18.39) across generations. This study demonstrated that desiccation stress differentially affected the survival of adult and nymphal kudzu bugs and may imply that environmental stress can affect the relative abundance of this species in the fields and around homes.

Functional analysis of Ultrabithorax in the wing-dimorphic planthopper Nilaparvata lugens (Stål, 1854) (Hemiptera: Delphacidae)

The homeotic complex (Hox) gene Ultrabithorax (Ubx) plays pivotal roles in modifying specific morphological differences among the second (T2), the third thoracic (T3), and the first abdomen (A1) segment in several insects. Whether Ubx regulates wing dimorphism and other morphological traits in the delphacid family (order Hemiptera) remains elusive. In this study, we cloned a full-length Ubx ortholog (NlUbx) from the wing-dimorphic planthopper Nilaparvata lugens, and identified two NlUbx isoforms. RNA-interference (RNAi)-mediated silencing of NlUbx in short-winged BPH nymphs significantly induced the development of wing-like appendages from T3 wingbuds, and this effect is likely mediated by the insulin/insulin-like signaling pathway. RNAi knockdown of NlUbx in long-winged BPH nymphs led to a transformation from hindwings to forewings. Additionally, silencing of NlUbx not only dramatically changed the T3 morphology, but also led to jumping defect of T3 legs. First-instar nymphs derived from parental RNAi had an additional leg-like appendages on A1. These results suggest that Ubx plays a role in determining some morphological traits in delphacid planthoppers, and thus help in understanding evolution of morphological characteristics in arthropods.

Biology, feeding and oviposition preference of Helopeltis theivora, with notes on the differential distribution of species of the tea mosquito bug species complex across elevations

Abstract Cocoa (Theobroma cacao L.) is an important beverage crop and commercially grown as a plantation crop. With the changing climate, the tea mosquito bug species complex, viz., Helopeltis theivora, H. bradyi and H. antonii, is emerging as a major threat to cocoa cultivation in India. Among the species of this complex H. theivora is responsible for causing considerable damage. The present investigations were carried out to find a weak link in the life cycle of H. theivora so it can be managed effectively. Specimens of the tea mosquito bug were found to first appear during the first week of September in South India. Helopeltis theivora requires on average 29.28 days to complete its life cycle on cocoa. The highest level of natural mortality was recorded in the first-instar nymph. The total developmental period of the fifth-instar nymph was significantly longer than that for the other nymphal instars. The sex ratio reflects that the population is highly female-biased, which may contribute to the dominant nature of this species in the cocoa ecosystem. Observation of the feeding and oviposition behavior of H. theivora revealed that the insect prefers to feed and oviposit on developing pods rather than on leaves and shoots. Analysis of the species distribution of tea mosquito bug at different elevations revealed that cocoa gardens situated less than 300 meter above mean sea level are dominated by H. theivora, whereas gardens situated more than 300 meter above mean sea level are dominated by H. bradyi. This separation of species across elevation may be driven either by abiotic or biotic factors.

Canopy parkour: movement ecology of post-hatch dispersal in a gliding nymphal stick insect, Extatosoma tiaratum.

For flightless arboreal arthropods, moving from the understory into tree canopies is cognitively and energetically challenging because vegetational structures present complex three-dimensional landscapes with substantial gaps. Predation risk and wind-induced perturbations in the canopy may further impede the movement process. In the Australian stick insect Extatosoma tiaratum, first-instar nymphs hatch on the forest floor and disperse toward tree canopies in the daytime. Here, we addressed how their tactic responses to environmental cues and movement strategies are adapted to the canopy environment. Newly hatched nymphs ascend with high endurance, travelling >100 m within 60 min. Navigation toward open canopies is underpinned by negative gravitaxis, positive phototaxis and visual responses to vertically oriented contrast patterns. Nymphal E. tiaratum also use directed jumping to cross gaps, and respond to tactile stimulation and potential threat with a self-dropping reflex, resulting in aerial descent. Post-hatch dispersal in E. tiaratum thus consists of visually mediated displacement both on vegetational structures and in the air; within the latter context, gliding is then an effective mechanism enabling recovery after predator- and perturbation-induced descent. These results further support the importance of a diurnal niche, in addition to the arboreal spatial niche, in the evolution of gliding in wingless arboreal invertebrates.

Direct and Indirect Impact of Artemisia judaica Extract on Euseius scutalis

The potential of extract of Artemisia Judaica L. against the predator Euseius scutalis (Athias-Henriot) and two kinds of prey that fed on them, first-instar nymphs of whitefly and second instar larvae of onion thrips, The results showed that, the effect of extract on B. tabaci nymphs recorded great decline in the rate of mortality to 26.8% compared to 81.6% respectively; The same results on T. tabaci larvae were increased from 23.95% to 77% respectively, by increasing the applied concentration from 125 to 2000 ppm., while when newly emerged E. scutalis adult treated with the same concentration of extract increased total percent mortality such increase was concentration dependent. Indirect exposure technique of is more effective than the direct exposure technique. Therefore, when using the plant extract and the predator in one control program is recommended to spray the extract first and then release the predator about 48 hours later.

Life-History Data of a Mexican Population of Triatoma nitida (Hemiptera: Reduviidae).

This study reports the third collection of Triatoma nitida Usinger in Mexico, with a brief description of the collection area and an investigation of parameters related to its vectorial capacity. Whether a triatomine (Hemiptera: Reduviidae) species is a primary or secondary vector is determined by factors that include vectorial capacity, anthropophilic habits, geographic distribution, and capacity to invade and colonize human dwellings. However, when the primary vectors are removed, secondary vectors, such as T. nitida, can become important transmitters of Trypanosoma cruzi Chagas to humans. To estimate the vectorial capacity of T. nitida, the egg-to-adult development time, number of blood meals required to molt to the adult stage, accumulative mortality, onset time for feeding, and feeding and defecation times were examined. Triatoma nitida (n = 100) required a median of 590 d to complete its development time, with a median of 31 blood meals. Almost half (46.5%) of the nymphs died during the cycle. The onset of feeding time exceeded 5 min in all nymphal instars (except on fourth-instar) and adults and feeding times exceeded 22 min in all instars, except on first-instar nymphs. No defecation was observed for 65.6% (n = 383) of the triatomines during a 30-min observation period. Based on the six parameters, the vectorial capacity of T. nitida should be considered as low. However, surveillance programs should include this species because the potential importance of T. nitida as a vector has been demonstrated in other countries.

Sticky traps as an early detection tool for crawlers of Adelges tsugae (Hemiptera: Adelgidae).

We developed an approach using sticky trap arrays as an early detection tool for populations of first-instar nymphs of the hemlock woolly adelgid (Adelges tsugae Annand), a pest of hemlocks (Tsuga spp. [Pinaceae]) in North America. We considered the detection rate of at least one nymph from trapping arrays consisting of one to six sticky panels, where we varied both the surface area of each trap that we assessed and the length of the trapping duration. We also estimated the time needed to set up, service, and assess groups of traps and attempted to relate capture of nymphs on traps to incidence and abundance of A. tsugae in the canopy above the traps. Arrays consisting of two traps provided a detection rate of 75% when 87.5% of the surface area of each trap was assessed, a process that required 38 min per array. The probability of detecting nymphs on traps left in the field for 5-6 d was similar to that for traps left for 12 d. The number of nymphs trapped in an array predicted the probability of finding A. tsugae in the canopy but only when all six traps were fully assessed. To reliably detect incipient A. tsugae infestations, we recommend placing arrays of traps at 1 km intervals along the perimeter of a stand during peak activity of first-instar sistentes nymphs and servicing these arrays every 5-7 d.

Age structure of bed bug (Heteroptera: Cimicidae) aggregations affects the nymphal feeding success

BackgroundBed bugs (Heteroptera: Cimicidae) are a group of blood-feeding ectoparasites. They mainly specialize on bats and birds, but a few species are important human pests. They exhibit several unique adaptations for their parasitic lifestyle. Among those, bed bug aggregations represent a striking example of a sub-social structure. However, their benefits for the bed bugs as well as their potential for bed bug control are largely unexplored. Young nymphs are known to disperse from the aggregations much less than older ones or adults. We therefore found possible that the aggregation age structure is connected with success in finding host and tested the effect of presence of adults on nymphal feeding success.ResultsWe tested the effect of presence of adults on feeding success of first-instar nymphs using an artificial feeding system. We found that presence of fed adults causes larger proportion of nymphs to feed.ConclusionsBased on our data, fed bed bugs seem to trigger the young nymphs to actively forage. Since the first instar is much less viable than later stages, our finding points to an adaptive behavior that economizes on foraging energy cost. In the context of bed bug control, knowledge on such behavior emphasizes the prevention of fed bed bugs from returning to harborages. Bed bug traps may thus be used not just as means of bed bug monitoring, but also as means of control.

Redescription of Neosimmondsia esakii Takahashi, 1939 (Hemiptera: Pseudococcidae)

Neosimmondsia esakiiTakahashi, 1939 is redescribed based on adult female syntypes and additional adult females from the Federated States of Micronesia. One of the examined syntypes is designated as lectotype. A complete illustration of the adult female is provided for the first time, and its diagnosis is amended. The first-instar nymph is illustrated for the first time. The host list of the species is enlarged to include Musaceae.

Description and Biological Studies of a New Species of Metaphycus Mercet, 1917 (Hymenoptera: Encyrtidae), A Parasitoid of Capulinia linarosae Kondo & Gullan.

The guava cottony scale, Capulinia linarosae Kondo & Gullan (Hemiptera: Eriococcidae), is an important pest of guava, Psidium guajava L. (Myrtaceae) in northern Colombia and Venezuela. A species of Metaphycus (Hymenoptera: Encyrtidae) is the only known primary parasitoid associated with this insect pest. The parasitoid is herein described as M. marensis Chirinos & Kondo, sp. nov., based on morphological characteristics of the adult female and male. Biological studies on adult longevity, fecundity, host preference, and sex ratio were conducted. The maximum longevity of the female and the male were 8.0 and 6.5 days, respectively, when fed with diluted honey. On average, a fed mated female laid approximately 40 eggs. Adult females of M. marensis were shown to prefer to parasitize 11- to 15-day-old adult females of C. linarosae and do not parasitize first-instar nymphs of the host eriococcid. The female-to-male sex ratio of the parasitoid was 2.24: 1. When ovipositing females of M. marensis were given only small-sized individuals (second-instar nymphs) of C. linarosae, generally the resulting progeny was a single male wasp. This parasitoid species has arrhenotokous reproduction and is a facultative gregarious parasitoid. These results show a short adult longevity, as well as a relatively low fecundity of the female compared with studies conducted on other Metaphycus species. This study provides essential baseline information for future biological control programmes for C. linarosae.

BUILDING TWO HOUSES ON A SINGLE HOST PLANT: GALLING INSECT SYNCHRONIZES ITS LIFE CYCLE WITH PLANT PHENOLOGY

Galls are specific interactions between specialist herbivores and their host plants. They are considered neoformed plant organs developed from cellular hypertrophy, tissue hyperplasia and cellular redifferentiation of the host tissues. Among several organisms capable of inducing galls, insects induce them with high morphological complexity. The induction and development of galls depend on the availability of responsive sites in the host plant that react to the chemical and/or mechanical stimuli of galling insects. The synchronization between the timing of availability of these responsive sites and the galling insect life cycle is essential for the establishment of the interaction. Galling insects are subject to several chemical, physiological and phenological changes in their host plant. Thus, changes in the host cycle may alter the insect's life cycle, distribution and abundance. This study focused on the morphological aspects and phenological relationship of the Matayba guianensis Aubl. (Sapindaceae) – Bystracoccus mataybae Hodgson, Isaias & Oliveira (Eriococcidae) system, carried out in a semi-deciduous forest located at the Estacao Ecologica do Panga (EEP), Uberlândia, MG, Brazil. We monitored the host plant phenology monthly from April 2015 to April 2016, and galls were sampled throughout the year to determine the stage of development of the galling insect. During leaf flushing, galling insects were collected every two days. The second-instar nymph induced leaf galls during leaf sprouting (peaks in September and October). The growth, development and maturation of the gall and of the galling insect occur concomitant to leaf maturation (peaks from February to May). Before the first leaves fall (August), the first-instar nymph moves from the senescent leaflet gall to branches and induces a stem gall, where it remains during part of the dry season until the next leaf flush. The synchrony between the life cycle of the galling insect and the host plant phenology maintains the univoltine cycle.

Taxonomy of coccids (Hemiptera: Coccidae: Coccus L.) associated with Crematogaster ants (Hymenoptera: Formicidae) in the stems of Macaranga plants (Euphorbiaceae) in Southeast Asia.

The Southeast Asian soft scale insects (Hemiptera: Coccomorpha: Coccidae) associated with ants of the Crematogaster borneensis-group (Hymenoptera: Formicidae) and living in the hollow stems of Macaranga plants (Euphorbiaceae) are revised taxonomically. Ten species of the genus Coccus L. are recognised: seven were described previously and three new species are described herein. The species are: Coccus caviramicolus Morrison, C. circularis Morrison, C. heckrothi Gullan Kondo sp. n., C. lambirensis Gullan Kondo sp. n., C. macarangicolus Takahashi, C. macarangae Morrison, C. penangensis Morrison, C. pseudotumuliferus Gullan Kondo sp. n., C. secretus Morrison and C. tumuliferus Morrison. All of these species are described or redescribed and newly illustrated based on the adult females, and a key to distinguish the species is provided. We designate a lectotype for C. macarangicolus. The first-instar nymphs of all species are morphologically extremely similar and therefore only the first-instar nymph of C. macarangae is described and illustrated. Seven of these species currently are known only from Macaranga, but C. macarangae, C. secretus and perhaps C. pseudotumuliferus have been recorded from the hollow stems of several other ant-plants and a few non-myrmecophytes. The Coccus species from Macaranga are closely related to C. hesperidum L., the type species of the genus, and therefore are retained in the genus Coccus even though the adult females exhibit a few morphological differences from C. hesperidum. The species of Coccus from Macaranga appear to be parthenogenetic because no male nymphs or adults have been found, despite extensive collecting.

Secondary metabolite contents in different parts of cassava plants infested by Phenacoccus manihoti Matile-Ferrero (Hemiptera: Pseudococcidae)

The objective of this study was to identify and quantify the secondary metabolites in different parts of cassava plants infested and non-infested by Phenacoccus manihoti. Experiments were conducted in a greenhouse at Embrapa Soja, Londrina, Parana, Brazil, with a completely randomized design involving a 3 × 2 × 2 factorial arrangement [i.e., three cassava cultivars (‘Baianinha,’ ‘Santa Helena,’ and ‘IAC-12’), two canopy strata (apical and basal), and two levels of P. manihoti infestation (infested and non-infested)]. Cassava cuttings were vertically positioned in 5-L plastic pots. To generate cassava plants infested with P. manihoti, leaves containing five mass-reared first-instar nymphs were collected and placed on shoot apices. After 48 h, samples were collected for a subsequent extraction of metabolites. Extract aliquots were analyzed by high-performance liquid chromatography to detect and quantify compounds. Extracts from the apical and basal leaves of ‘Baianinha,’ ‘Santa Helena,’ and ‘IAC 12’ cassava cultivars contained caffeic acid, p-coumaric acid, ferulic acid, rutin, and trace amounts of gallic acid. Caffeic acid was mainly detected in the basal leaf extracts for all evaluated cultivars. Additionally, ferulic acid levels were relatively high in the ‘Baianinha’ and ‘Santa Helena’ basal leaves. Furthermore, rutin concentrations were higher in apical leaves than in basal leaves for all three cultivars, regardless of whether the plants were infested by P. manihoti. The presence of P. manihoti induced the production of rutin in the apical leaves of ‘Baianinha’ plants.