Raoiella Indica Research Articles

Exudate droplets incorporated on eggs by Raoiella indica Hirst female during oviposition may avoid the predation of Amblyseius largoensis (Muma).

Raoiella indica Hirst has rapidly and widely spread throughout the New World since 2004, primarily infesting coconut palms and interacting with the predator Amblyseius largoensis (Muma). Although A. largoensis feeds on R. indica at all stages of development, it cannot naturally reduce its population to levels that do not impact the host plant. Raoiella indica possesses dorsal setae that secrete exudates during all post-embryonic developmental stages, and females have a behavior that deliberately deposits droplets on the freshly laid egg, possibly as a defense strategy against predation in vulnerable stages. In this context, we analyzed whether the presence or absence of droplets in R. indica eggs affects predation using A. largoensis as a biological model. Thus, we evaluated whether some biological and behavioral characteristics of A. largoensis could be affected by the consumption of R. indica egg masses washed or unwashed with water. Also, we performed a chemical analysis of the droplets exuded by R. indica and provided a description of the oviposition behavior of R. indica. The predator showed a higher consumption rate and preference for washed eggs. The results suggest that the exudate droplets have defensive functions, which are incorporated by the female onto the egg during oviposition and subsequently during a patrolling behavior, as they lose their effect after being washed with water. Although the droplets do not prevent the predator from feeding, they reduce the number of R. indica eggs consumed without affecting the growth of A. largoensis.

Acaricidal and repellent activities of botanical extracts on Raoiella indica Hirst (Acari: Tenuipalpidae) in Northeast Brazil

ABSTRACT The toxicity and repellence of aqueous extract of Sarcomphalus joazeiro (Mart.) Hauenschild (Rhamnaceae) leaves and hexane extract of Annona muricata L. (Annonaceae) seeds in different concentrations were evaluated on Raoiella indica Hirst (Acari: Tenuipalpidae). To determine the toxicity, banana leaf discs were immersed in the extract solutions and infested with adult females of R. indica. Mortality was assessed after 72 hours. Repellence was evaluated on banana leaf discs treated or not with the extract solutions. After 72 hours, mortality ranged from 24% to 72% for the S. joazeiro extract and from 33.75 to 96.25% for the A. muricata extract. Concentrations of 20% and 25% (m/v) of S. joazeiro extract, and 0.1%, 0.2%, 0.4%, 0.8% and 1.00% (v/v) of A. muricata extract were considered toxic because the mortality caused by them (62%, 72%, 33.75%, 40%, 66.25%, 88.25%, and 96.25%, respectively) differed from the untreated (16% and 1.25%, respectively). No S. joazeiro extract concentration caused repellence, but concentrations of 0.4%, 0.8%, and 1% (v/v) of A. muricata extract were repellent to the mite. Both evaluated extracts have potential for use in the management of R. indica due to their toxicity, especially that of A. muricata, which is also repellent to the mite.

Acaricidal potential of Bidens pilosa in the control of the red palm mite

Raoiella indica Hirst, 1924 (Prostigmata: Tenuipalpidae), is one of the leading pest mites on plants of the Arecaceae family, especially palm and banana trees. This species has a high reproductive capacity and rapid dissemination, but the control methods available for this species are still limited. Therefore, this work aimed to evaluate the acaricidal effect of blackjack (Bidens pilosa) on adult individuals of R. indica. The experiment was conducted in a completely randomized design, using the plant structures of blackjack to prepare the extracts. The experimental units consisted of coconut leaf discs (4 cm), with moistened cotton at the bottom of the Petri dish (10.0 × 1.2 cm), and around the disc to maintain turgidity and prevent mites from escaping. Spraying was carried out on 12 adult females of R. indica per sample unit, with seven repetitions for each concentration, using an airbrush with a constant pressure of 1.3 psi and 1 mL of solution per repetition plate. The acaricidal effect was evaluated 12, 24, 36, 48, 60, and 72 hours after spraying. The mortality of R. indica was proportional to the increase in the concentration of the blackjack plant extract, and the lethal concentrations obtained, CL50 and CL 90, were estimated between 1.49% and 4.19%, indicating the acaricidal potential of B. pilosa. Phenolic compounds were the majority of compounds found in this study.

Impact of Raoiella indica Hirst (Acari: Tenuipalpidae) Infestation on Nitrogen Concentration of Areca catechu L.

Different tenuipalpid phytophagous mites might infest the foliage and nuts of the areca palm and cause significant damage. Raoiella indica (Hirst), has been known as a serious pest of areca palm. In the present study, concentration has been fixed on exploring the feeding impact of R. indica through the quantitative estimation of nitrogen concentration of mite-infested and uninfested leaves by ‘Kjeldahl method (1883)’. Results of the study have exposed that the feeding activity of the mite on the leaves of A. catechu has induced severe reduction in the levels of ‘total nitrogen’. The percentage loss of ‘total nitrogen’ was estimated to be 37- 62% in RPM-infested Areca leaves. Loss of nitrogen content as evidenced during the present study disclosed the potential of R. indica on A. catechu.

Efficiency of Citrus limon L. Ripe Peel Extract In The Control of Raoiella indica (HIRST, 1924) (Prostigmata: Tenuipalpidae)

Purpose: This study aimed to evaluate the acaricidal potential of the aqueous extract obtained from the ripe peels of Citrus limon on adults of Raoiella indica. Theoretical Reference: R. indica is a phytophagous mite that primarily attacks plants of the Arecaceae family. As it is considered a relatively new pest in Brazil, there are few control methods available, with synthetic chemical control being the primary one. Method: The ripe peels of C. limon were dried and ground into a fine powder, which was used to formulate extract concentrations of 0.00, 1.00, 1.64, 2.70, 4.44, 7.30, and 12.00%. The extracts were sprayed on 12 adult females of R. indica per experimental unit, with 7 repetitions for each concentration. Mortality was assessed at 24, 48, and 72 hours after spraying. Results and Conclusion: The mortality of R. indica increased as the concentrations of the ripe peel extract of C. limon increased, reaching 88% for the highest concentration after 72 hours of application. Research Implications: The aqueous extract of ripe peels of C. limon demonstrated acaricidal efficiency against R. indica under controlled conditions. Originality/Value: This work adds value to the study of alternative methods of agricultural pest control, as a means of promoting more economically and ecologically sustainable management.

SEMENTES DE MAMÃO EM DIFERENTES ESTÁGIOS DE DESENVOLVIMENTO SÃO EFICAZES NO CONTROLE DO ÁCARO VERMELHO DA PALMEIRA?

Objective: To evaluate the acaricidal potential of papaya fruit seed (C. papaya L.) extracts at different phenological stages of development on the red palm mite. Methods: Extracts from green and ripe seeds, diluted at different concentrations, were sprayed on adult mites in a completely randomized design using Petri dishes with discs of dwarf coconut leaf. The acaricidal effect was assessed at intervals of 12 hours up to 72 hours after spraying. Results and Conclusion: The mortality of Roiella indica was proportional to the increase in extract concentrations for both green and ripe papaya fruit seeds. It was concluded that aqueous extracts from green and ripe papaya fruit seeds exhibit acaricidal activity against adult red palm mites under laboratory conditions. Research Implications: Papaya seeds at different stages effectively controlled red palm mites under laboratory conditions. Originality/Value: This research contributes by exploring the potential of an agricultural residue as a pest control agent in agriculture and demonstrating its potential for more sustainable agricultural practices.

Predation of Raoiella indica (Acari: Tenuipalpidae) by Stethorus tridens Gordon (Coleoptera: Coccinellidae)

The red palm mite (RPM), Raoiella indica Hirst (Acari: Tenuipalpidae), is an invasive species in several American countries and has a wide range of hosts, causing significant damage, mainly to coconut and banana crops. Previous studies conducted in America have focused on the biological control of RPM through predatory mites and insects. Stethorus tridens Gordon (Coleoptera: Coccinellidae) is considered a promising biocontrol agent of phytophagous mites it has been observed on several cultures, and has a high predatory capacity. The aim of this study was to investigate S. tridens preferences among different developmental stages of RPM and estimating the functional and numerical responses of S. tridens over its most preferred prey-stage. Furthermore, the prey preference of S. tridents was examined between eggs of Tetranychus evansi Baker and Pritchard (its natural prey) and eggs of RPM through two-choice and non-choice experiments. The results showed that S. tridens prey on all developmental stages of RPM, with a marked preference for eggs over other stages of RPM. The functional response of this predator was type III, as consumption increased rapidly at intermediate egg densities. Predation on RPM eggs was unable to stimulate S. tridens reproduction, even at the highest densities. When we compared the food preference of S. tridens to eggs of T. evansi and RPM, we found that the predator preferred tetranychids. The results of this study suggested that RPM can be used as alternative prey to S. tridents, serving as a source of energy and allows for maintenance but not its reproduction.

Resistance of dwarf Cocos nucifera L. (Arecaceae) cultivars to Raoiella indica Hirst (Acari: Tenuipalpidae).

The red palm mite Raoiella indica Hirst, 1924 (Acari: Tenuipalpidae) is an important pest of the coconut palm Cocos nucifera L. (Arecaceae) and has caused problems in coconut production worldwide. Research has been carried out aiming at controlling the mite through chemical, biological, alternative, and host plant resistance methods. Identifying coconut palm cultivars resistant to R. indica is important to reduce the problems caused to plantations. Therefore, the objective of this work was to evaluate the performance of R. indica in six dwarf coconut palm cultivars, to identify sources of resistance. The cultivars of the sub-varieties green, red, and yellow evaluated were Brazilian Green Dwarf-Jiqui (BGDJ), Brazilian Red Dwarf-Gramame (BRDG), Cameroon Red Dwarf (CRD), Malayan Red Dwarf (MRD), Brazilian Yellow Dwarf-Gramame (BYDG), and Malayan Yellow Dwarf (MYD). Confinement and free choice tests of R. indica on the cultivars were performed, in which biological parameters and preference were evaluated. Mite performance was different in the cultivars evaluated. In the confinement bioassay, R. indica had the worst performance in the cultivar BGDJ, the best performance in CRD, MRD, and BRDG, and intermediate performance in BYDG and MYD. In the free choice test, the cultivars MRD and MYD were preferred in relation to BGDJ, and CRD was less preferred in relation to BGDJ. Therefore, we considered that the cultivar BGDJ is the most resistant to R. indica, by antibiosis and antixenosis; CRD has resistance by antixenosis; and MRD, BRDG, BYDG, and MYD are susceptible.

Eruca Vesicaria (Arugula) Extract: Possible Acaricidal Effect Against Red Palm Mite

Purpose: Therefore, this study aimed to use the crude extract of Eruca vesicaria (arugula) leaves in the management of Raoiella indica. Theoretical reference: The red palm mite is an invasive species and is considered a pest of great importance for coconut and banana trees and other plants in the Arecaceae family. Therefore, this study aimed to use the crude extract of Eruca vesicaria (arugula) leaves in the management of Raoiella indica. Method: For this, fine powder from arugula leaves was used diluted in water and Tween® adhesive spreader, in concentrations of 1.0; 1.58; 2.51; 3.98; 6.31, and 10.0 %. These extracts were sprayed on 10 adult females of R. indica per sample unit, with 10 replicates for each concentration. The acaricidal effect was evaluated at different time intervals after spraying: 12, 24, 36, 48, 60, and 72 hours. Results and conclusion: The results demonstrate that mortality of the R. indica mite increases as the concentration of arugula vegetable extract increases, with lethal concentrations above 3.98 % being indicated for control. Research implications: The aqueous arugula extract, in its different concentrations, demonstrated acaricidal efficacy against the red palm mite under laboratory conditions. Originality/value: This text adds value to fields of study such as alternative insect control in crops and sustainability, proposing a change in the ecologically responsible behavior of farmers.

The association between the exotic species Raoiella indica Hirst and the predator Amblyseius largoensis (Muma) may cause displacement of the native species Oligonychus pratensis (Banks)

The association between the exotic species Raoiella indica Hirst and the predator Amblyseius largoensis (Muma) may cause displacement of the native species Oligonychus pratensis (Banks)

BIOLOGICAL CONTROL OF DATE PALM RED MITE RAOIELLA INDICA USING ORGANIC MITICIDE

The red palm mite Raoiella indica Hirst is spread throughout the Caribbean islands, Florida, northern South America, and Mexico, and it negatively impacts palm and banana species. Different acaricides were used to control R. indica infestations of date palms in the UAE, but the majority of these acaricides are strong chemicals with high toxicity to non- target pests. The present study was conducted in the UAE on the red palm mite R. indica on infected date palms. One of the commercial botanical acaricides, namely M Impact, was tested for the control of R. indica in comparison with a market product containing abamectin. Raoiella indica mortality was 79.40% after the first spray and 70.23% after the second spray in the treatment of M Impact, with a 58.4% reduction in eggs. In the market product containing 3.5% w/v abamectin, mortality was 46.53% after the first spray and 41.22% after the second spray, with a 34.2% reduction in egg mortality. In this study, it was demonstrated that the organic miticide M Impact outperformed its chemical counterpart, abamectin. Organic miticides have provided significant and long-term control of the date palm red mite, R. indica.

Selectivity of acaricides to Neoseiulus barkeri (Hughes) (Acari: Phytoseiidae)

AbstractNeoseiulus barkeri Hughes has been used to control several pests, including the red palm mite, Raoiella indica Hirst. However, in some situations, the exclusive use of biocontrol agents is not sufficient to prevent the damage caused by pests. In these scenarios, the integration of chemical and biological controls is desired. For that purpose, the determination of selective acaricides, avoiding or reducing deleterious effects on the biological control agent is desirable. This study evaluated the lethal and sublethal effects of acaricides (abamectin, azadirachtin, fenpyroximate and pyridaben) on the predatory mite N. barkeri. We investigated the toxicity and selectivity of the acaricides and the survival, fertility, egg viability and instantaneous growth rate (ri) of N. barkeri exposed to acaricides. Additionally, we classified the acaricides according to the scale proposed by the International Organization for Biological Control (IOBC). Among the acaricides evaluated, abamectin was selective for N. barkeri because the estimated lethal concentration (LC50) for N. barkeri was higher than that for R. indica. None of the acaricides affected predator survival curves. However, azadirachtin and fenpyroximate reduced the average predator survival time. Pyridaben was the only acaricide that reduced the fertility of N. barkeri females and, consequently, their instantaneous growth rate (ri). All the acaricides affected the viability of N. barkeri eggs. Pyridaben was classified as moderately harmful, whereas other acaricides were classified as harmless.

Pollen as sole food source for two generalist predatory mite species (Acari: Phytoseiidae)

Amblyseius largoensis and Typhlodromus ornatus (Acari: Phytoseiidae) are generalist predatory mites that naturally inhabit coconut plantations and other tropical crops. We assessed the suitability of two coconut pest mites, Raoiella indica (Acari: Tenuipalpidae) and Aceria guerreronis (Acari: Eriophyidae); the storage mite Tyrophagus putrescentiae (Acari: Acaridae); honey; and the pollens of castor bean, Ricinus communis, and cattail, Typha domingensis, and their mixture, as food sources for the mass rearing of A. largoensis and T. ornatus. Both pollens, supplied singly or mixed, generated the highest progeny production by both A. largoensis and T. ornatus, and were therefore selected for further life table studies. The pollen diets did not influence the survival of A. largoensis whereas there was higher survivorship of T. ornatus fed on the mixed pollen diet than on R. communis pollen alone. The maximum oviposition rate of both A. largoensis and T. ornatus occurred at the beginning of adulthood, irrespective of the pollen diet. Overall, the life table parameters indicated that the pollen of R. communis for A. largoensis, and R. communis with the mixed pollen diet for T. ornatus, were the best regarding population growth and reproduction. Collectively, our results indicate that A. largoensis and T. ornatus can survive and reproduce excellently when fed solely on R. communis or on the mixed pollen diet. In addition, these results point to the potential of pollen supplementation for the enhancement of the efficiency of these predators in conservation biological control.

Alternative Management of Raoiella Indica Hirst, 1924 (Acari: Tenuipalpidae) With Passion Fruit Seed Extract

Objective: The aim of this work was to evaluate the acaricidal potential of the passion fruit seed extract (Passiflora edulis) in controlling the red palm mite (R. indica). Theoretical framework: Raoiella indica is a pest mite of agricultural interest, considered one of the main pests of banana, coconut, date palm, and ornamental crops. Method: The experiment was conducted in a completely randomized design using passion fruit seed extract, with 7 repetitions and 12 R. indica individuals per repetition. The concentration tested was 1.0; 1.72; 2.95; 5.08; 8.73, and 15.0 %. The experimental units consisted of coconut leaf discs (4 cm in diameter) with moist cotton at the bottom of the Petri dish (10.0 x 1.2 cm) and around the disc to maintain turgidity and prevent the mites from escaping. The application was carried out using an airbrush, connected to a compressor calibrated with a constant pressure of 1.3 psi and 1 mL of solution per plate. The evaluation was conducted at intervals of 24, 48, and 72 hours following the extract's spraying. Results and discussion: Mortality was observed in the dose-response model, the concentration of 15 % showed mortality rates greater than 98.8 % of individuals. Amounts of phenolics of 10.242, tannins of 14.837, and flavonoids of 9.700 in mg g-1 were found, attributing the mortality of individuals to the presence of these compounds. It was concluded that the passion fruit seed extract has an acaricidal effect on R. indica in the laboratory. Implications of the research: Alternative pest management has grown substantially in recent years, given the demand for more sustainable products in the agricultural field. The use of botanical extracts is beneficial to the environment, as it does not promote soil and water contamination and can be an efficient method for controlling agricultural pests. Originality/value: This article adds value to research areas such as alternative management of agricultural pests, and sustainability and suggests a change in the environmentally conscious behavior of rural producers.

Effect of study area extent on the potential distribution of Species: A case study with models for Raoiella indica Hirst (Acari: Tenuipalpidae)

Ecological niche models are used to quantify the relationships between known occurrence records of a given species and environmental variables at these locations. Maxent is among the most widely used algorithms for modeling species distribution and has demonstrated better performance compared to other methods. However, the extent of the study area is a critical issue in the development of presence-only species distribution models because it encompasses the region used to extract the background points employed to characterize the environments accessible to the species. Thus, this study evaluated the effect of the extension of the study area on the species distribution modeling with the Maxent algorithm and occurrence data from the invasive species Raoiella indica Hirst (Acari: Tenuipalpidae). The increase in the study area extent inflated most of the threshold-dependent and -independent metrics used to assess model performance. The selection of the study area also affected the predicted suitable areas for the species (its potential distribution). The analysis shows that models developed with smaller study areas resulted in model overfitting and an increase in false-negative predictions. The extent of the area used during model training has a strong influence on the model outputs, with significant consequences for predicting the potential distribution of invasive species and thus for the areas under risk of invasion.

Plants harbouring the red palm mite Raoiella indica Hirst (Acari: Tenuipalpidae) in Alagoas State, Northeast Brazil, with novel host associations

N/A

Effect of cues from Amblyseius largoensis (Muma) on the oviposition behavior of Raoiella indica Hirst

The ability of an organism to defend itself and protect its offspring is closely related to the evolutionary success of the organism. In this study, we examined the responses of red palm mite, Raoiella indica Hirst, to predation risk using cues from the predator Amblyseius largoensis (Muma). Females of A. largoensis were used for the production of cues for 4 h in two types of bioassays, a choice and no-choice tests. The oviposition rate of R. indica was evaluated until to 96 h. In addition, a walking behavior test was conducted (distance/time walked and resting time). For both tests, a control treatment without cues was done. In the no-choice bioassay, the oviposition rate of R. indica decreased by 55% when the cues were present. In the choice bioassay, the oviposition rate was similar to the control treatment, however most of the eggs were deposited in the site without cues. The walking behavior of R. indica was not affected by the presence of predator cues in no-choice bioassay. In choice bioassay, R. indica stayed longer in sites without cues. A. largoensis cues seem to be strong signs of predation risk affecting R. indica oviposition when there is no-choice, even after 96 h. R. indica shows that it is able to identify the cues of A. largoensis. We clearly evidenced the anti-predation behavior of R. indica, showing the trade-off between predation risk and reproduction on A. largoensis cues.

Extracts of plant residues from soursop peels in the management of palm red mite

Raoiella indica Hirst, 1924 (Prostigmata: Tenuipalpidae), is one of the main pest mites of palm and banana trees, causing significant damage in producing regions. Thus, the objective of this work was to evaluate the acaricidal effect of soursop peel extract (Annona muricata L.) on R. indica adults. The experiment was conducted in a completely randomized design using soursop peel extract, with 7 replications and 12 individuals of R. indica per replication. The experimental units consisted of discs of coconut palm leaves (4 cm in diameter), with cotton moistened at the bottom of the Petri dish (10.0 x 1.2 cm) and around the disc to maintain turgor and prevent mites from escaping. The application was carried out using an airbrush, connected to a calibrated compressor with a constant pressure of 1.3 psi and 1 mL of solution per plate. The acaricidal effect was evaluated 24, 48, and 72 hours after spraying. Mortality data were corrected and subsequently submitted to probit analysis (p≤0.05) using the statistical program R, with the LC50 and LC90 of the extract being calculated. The soursop peel extract at the maximum concentration used (15%) showed mortality of 80% of individuals of R. indica. The LC50 was 1.934%. It was concluded that extracts from soursop peel have acaricidal potential on R. indica in the laboratory.

Palm Red Mite Management with Soursop Seed Plant Residue Extracts

Raoiella indica Hirst, 1924 (Prostigmata: Tenuipalpidae), is one of the leading pest mites in palm and banana trees, however, there are few control methods available for this pest species. Therefore, this work aimed to evaluate the acaricidal effect of soursop seed extract (Annona muricata L.) on R. indica adults. The experiment was conducted in a completely randomized design using soursop seed extract with 7 replicates and 12 individuals of R. indica per replicate. The experimental units consisted of discs of coconut palm leaves (4 cm in diameter), with cotton moistened at the bottom of the Petri dish (10.0 × 1.2 cm) and around the disc to maintain turgor and prevent mites from escaping. The application was performed using an airbrush, connected to a calibrated compressor with a constant pressure of 1.3 psi and 1 mL of solution per repeat plate. The acaricidal effect was evaluated 24, 48, and 72 hours after spraying. Mortality data were corrected and submitted to Probit analysis (p ≤ 0.05) using the statistical program R, with the LC50 and LC90 calculated for the extract. At the maximum concentration (15%), the soursop seed extract showed mortality of 70% of individuals of R. indica, and the LC50 was 6.58%. It was concluded that the soursop seed extract showed acaricidal potential on R. indica in the laboratory.

Impacts of continental invasion of Raoiella indica in the Americas

The invasion of the Red Palm Mite (RPM), Raoiella indica, in the western hemisphere, is probably the most extensive, fastest, and better-documented plant pest arthropod invasion in recent decades. RPM was initially detected in the Lesser Caribbean Antilles, and it rapidly spread hooping through the islands and reaching continental areas in North, Central and South America.