Experimental and Applied Acarology最新文献

Neoseiulus californicus (McGregor) is one of the main predators belonging to the family Phytoseiidae classified as a type II generalist predator that has been used to control greenhouse pests such as thrips, eriophyids, and spider mites. One of the significant ways to recognize the efficacy of the phytoseiid predatory mites is the study of their foraging behavior. Mutual interference is a negative relationship between a predator's searching efficiency and its density. This study appraised the effect of the age-dependent mutual interference of N. californicus on larvae and nymphs of Tetranychus urticae Koch under laboratory conditions at 25 ± 1℃, 70 ± 5% RH and a photoperiod of 16 L: 8D h. To determine the per capita searching efficiency and interference coefficient, Nicholson's model and linear regression were used, respectively. The results showed that the total predation of N. californicus reared on T. urticae nymphs was significantly affected by predator density and age. In addition, per capita searching efficiency of the predator significantly declined with predator density, which is the result of mutual interference. Furthermore, the slope of the linear regression (m) between the logarithm of per capita searching efficiency and the logarithm of the predator density increased, ranging from - 0.465 in 5-day-old individuals to -0.1452 in 40-day-old individuals. The negative effects of mutual interference decreased along with growing age. Our findings showed that in different tested ages, the rate of interference among adults differed compared to immature individuals. These results suggest that age-specific differences in mutual interference should be considered when optimizing the mass rearing and field release of predators for the biological control of T. urticae.

Herewith we present the first detection of Amblyomma lepidum (Dönitz, 1909) on cattle in Zimbabwe. Zimbabwe's smallholder farmers rely heavily on their livestock, mainly cattle and goats. Even though great importance is placed on cattle farming, no systematic surveillance of tick and tick-borne diseases is currently being conducted in the country. Forming part of the Amblyomma genus, A. lepidum is a brightly ornate tick with great vector potential, which could have harmful effects on cattle and cattle farming in Zimbabwe. This report documents the presence of both male and female A. lepidum ticks that were morphologically identified, and with the use of two ribosomal genes, were molecularly characterised as A. lepidum. Hypotheses can be made as to how this tick was introduced into Zimbabwe; however, its presence highlights the need for a systematic surveillance programme to track not only new introductions, such as the aforementioned, but the current distribution of this tick population in Zimbabwe.

Chigger mite larvae are well adapted parasites, mainly of vertebrates, and can play a role as potential vectors for pathogens, as is the case of the bacteria Orientia tsutsugamushi. In Brazil, 63 species of chiggers have been cataloged, eight of which were found parasitizing bats. Until now, no studies have monitored pathogens of bat-associated chigger species in the Americas. Here, we provide information about the detection of Ehrlichia sp. (16S rRNA gene) in Perissopalla ipeani Brennan larvae collected parasitizing the bat species Carollia perspicillata in Brazil.

The biology and predation of the generalist predator, Chrysoperla carnea (Stephen) (Neuroptera: Chrysopidae) were studied while feeding on motiles of two economically important spider mite pests: citrus brown mite (CBM), Eutetranychus orientalis (Klein) (Acari: Tetranychidae) and date palm mite (DPM), Oligonychus afrasiaticus (McGregor) (Acari: Tetranychidae) under low relative humidity (RH) (35 ± 5%). Results showed that the predator larvae did not pupate when fed on CBM and DPM motiles at both low and high RH. The shortest total predator larval duration was against motiles (14.65 ± 0.15 days) and eggs (15.42 ± 0.80 days) of CBM at low and high RH, respectively. Adult longevity, however, was higher when C. carnea was fed on the eggs of Ephestia cautella (Walker) (Lepidoptera: Pyralidae) (male: 32.00 ± 1.61 days; female: 36.75 ± 0.25 days) than CBM eggs (male: 13.00 ± 0.00; female: 31.00 ± 2.00). The highest total predation by the predator larvae were found against the eggs of CBM (12671.11 at high RH) followed by motiles of CBM and DPM (4696.53 and 4088.16 at low RH), respectively. Considering the significance of CBM and DPM as a pest in the arid climate of Saudi Arabia, it is essential to understand how C. carnea responds to these pests at low RH. These results depict that the predator larvae voraciously fed on eggs and motiles of mite pest species revealing its potential use as a biological control agent against spider mites at both low and high RH levels. The high predation rate and completion of life cycle on the eggs of CBM could also be considered as satisfactory indication of the potential use of C. carnea larvae for spider mite management. The inability of the predator larvae to complete the life cycle against motiles of CBM and DPM could help to devise a management plan for multiple/repeated releases of the predator larvae.

The Asian longhorned tick, Haemaphysalis longicornis Neumann, is a species commonly found in Central Asia, East Asia, and Australia, but it has recently emerged in the USA as a significant disease threat. The tick exhibits a fascinating biological trait, as certain populations are capable of reproducing both sexually and asexually via parthenogenesis. As a result, a single asexual female has the potential to initiate the establishment of a new population when introduced into a novel geographical region. Haemaphysalis longicornis is of considerable medical and veterinary importance, being associated with more than 30 human pathogens, including Anaplasma, Babesia, Bartonella, Coxiella, Rickettsia, Theileria, and others. It is also a competent vector for the severe fever with thrombocytopenia syndrome virus (Bunyaviridae, Phlebovirus) in Eastern Asia. The tick can also cause heavy infestations in cattle and transmit the hemoprotozoan parasite Theileria orientalis genotype Ikeda, resulting in significant economic losses within the cattle industry. In the present study, we report the morphological and molecular identification of H. longicornis in the European part of Türkiye. Additionally, we offer hypotheses regarding how H. longicornis ticks may have arrived in Türkiye, potential risks, and the necessary precautions that should be taken.

The spider mite species Tetranychus gloveri Banks has emerged as a major pest of adenium in Kerala, South India. The sole reliance on synthetic acaricides for mite management has led to the development of resistance in T. gloveri populations, highlighting the need for alternative management strategies. The phytoseiid mite, Neoseiulus longispinosus Evans is a widely distributed predator of spider mites, adaptable to warm temperatures. The present study evaluates the efficacy of N. longispinosus against T. gloveri on adenium in the laboratory through functional and numerical response studies and in the polyhouse by a pot culture experiment. The functional response of N. longispinosus was studied on different life stages of T. gloveri, while the numerical response was studied on adult T. gloveri at different densities in a modified Munger cell. The pot culture experiment was conducted in completely randomised design (CRD) by releasing predators twice at 10-day intervals, at different predator-prey ratios of 1:25, 1:50, 1:75, 1:100, and 1:125 on adenium plants infested with T. gloveri. The functional response of N. longispinosus to all life stages of T. gloveri provided evidence for a Type-II response. The predator consumed all stages of T. gloveri, exhibiting the highest preference for the eggs, followed by the larvae, protonymphs, deutonymphs, and adult stages. The numerical response studies carried out at different densities revealed that the oviposition rate of the predator increased with an increase in prey density and prey consumption, recording a maximum of 3.05 eggs/day at the prey density of 12. In the polyhouse, the narrow predator-prey ratios of 1:25 and 1:50 significantly reduced the mite population to the tune of 94.50 and 61.95 per cent, respectively, after two releases of the predator, while the ratio 1:75 brought about 28.98 per cent reduction. However, wider predator-prey ratios were not effective.

This study evaluated the acaricidal activity of the natural terpene linalool against Rhipicephalus microplus larvae. Four tick populations from different cattle farms with a history of acaricide resistance were selected. The Larval Packet Test (LPT) was used to determine the lethal concentrations (LC50 and LC90) of linalool, cypermethrin, and the combination of LC50 linalool and cypermethrin. Linalool was tested at concentrations ranging from 0.0975 to 50%, while cypermethrin was tested between 0.01% and 3%. The results demonstrated that linalool alone had LC50 values varying across the populations, ranging from 0.5 to 4.33%, and LC90 values ranging from 2.57 to 7.61%. When linalool was combined with cypermethrin, the required concentrations of cypermethrin to achieve LC50 and LC90 were significantly reduced (p ≤ 0.05). This reduction in cypermethrin dosage was observed across all tested populations, indicating that linalool can enhance the acaricidal efficacy of cypermethrin. Integrating linalool with cypermethrin could therefore be valuable for tick management strategies, particularly in reducing reliance on high doses of these acaricides.

Amblyseius orientalis Ehara (Mesostigmata: Phytoseiidae) has garnered significant attention as an effective predatory mite for controlling spider mites in fruit production in China. However, despite its considerable potential for pest management, A. orientalis may face food shortages during transportation and field application. Currently, there is a lack of information on the effects of starvation on the development, survival, and reproductive capacity of A. orientalis. In this study, we evaluated the impact of starvation on the development, survival and reproduction of A. orientalis. We found that female adults exhibited greater tolerance to starvation than larvae and protonymphs. Approximately 50% of the female adults survived after eight days of starvation. Interestingly, starvation during the early developmental stages extended lifespan, nearly doubling male longevity from 20.56 to 38.00 days, and increasing female longevity from 44.68 to 70.31 days. However, starvation in female adults reduced egg production from 18.46 to 5.33 eggs over a period of ten days, while male reproductive abilities increased from 18.46 to 19.41 eggs. Additionally, the sex ratio of the offspring was not influenced by paternal starvation, but maternal starvation resulted in a male-biased offspring ratio. In conclusion, our study demonstrates that A. orientalis can tolerate starvation at various life stages, enabling it to withstand food shortages during both transportation and application.