Resistance of Common Bean Genotypes to the Broad Mite, Polyphagotarsonemus latus (Banks, 1904) (Acari: Tarsonemidae): Offspring Development and Biochemical Basis

The broad mite (BM) Polyphagotarsonemus latus is a pest of great prominence for several crops, including the common bean (Phaseolus vulgaris). The objective of this study was to select resistant genotypes and to determine chemicals associated with resistance. In the first experiment, BM incidence was assessed for 36 genotypes in a greenhouse study. A group of 10 genotypes was selected according to the development of BM populations. Mite populations and phytometric and biochemical variables were then determined to study eventual differential genotypic responses to mite infestation. Lower numbers of mite mobile forms (larvae + adults) were found on Verdão, Negrão and Carioca Original genotypes. The magnitude of differences reached 5.4 times more BM in the IAC Alvorada than the Verdão genotype. Plant yields were reduced for the genotypes TAA Bola Cheia, IPR Sabiá, IPR Uirapuru, IAC Alvorada and Carioca Original when plants were infested with BM. The yields for LP 13833, BRS Esteio, Negrão 11, Verdão and MD 1133 were similar between infested and non-infested genotypes, indicating tolerance. Verdão and Negrão 11, besides the tolerance, exhibited low offspring development, indicating antibiosis and/or antixenosis. Higher phenolic compound levels were found in the Verdão genotype. Increased contents of catalase and peroxidase were detected for Negrão 11 genotype when infested with BM. This work allowed the detection of common bean genotypes that express resistance and tolerance to BM. These genotypes can be used in places with a history of BM infestation, or used in breeding programs to incorporate these characteristics in other genotypes.

Population Trend, Crop Loss Assessment & Acaricidal Management of Polyphagotarsonemus latus (Banks) (Acari: Tarsonemidae) Infesting Mungbean Under Gangetic Basin Of West Bengal, India

Mungbean (Vigna radiata (L.) Wilczek), also known as green gram, is one of the important pulse crops grown in West Bengal, India. Mungbean is affected by various insect and non-insect pests, among which the yellow mite, Polyphagotarsonemus latus (Banks) plays an important role amounting huge crop loss. The peak population of the mite (23.2 mites/sq.cm leaf area) encountered during the initial budding stage of the crop and declined thereafter at the end of flowering stage. A tune of 50–80 % crop loss was estimated due to its infestation. Among seven acaricides tested, Dicofol, Diafenthiouron and Spiromesifen showed higher efficacy against the mite than the other acaricides used. The yellow mite is a regular and major pest of mungbean which appeared in a severe form in the farmer field especially during pre-kharif season which can be manage successfully by application of two successive round of acaricides like diafenthiouron or dicofol at 10 days interval during early reproductive stage of the crop that ensure the flowering and fruit setting of the crop giving satisfactory yield. The present study provides an important finding regarding the peak season of infestation by yellow mite and the effective measures to be taken against it which will help the mung bean growers to combat the loss from this havoc.

Evaluation of indigenous fungal entomopathogens and aqueous leaf extract of Annona muricata against Polyphagotarsonemus latus infesting Jatropha curcas in Indonesia

Puspitarini RD, Afandhi A, Fernando I. 2021. Evaluation of indigenous fungal entomopathogens and aqueous leaf extract of Annona muricata against Polyphagotarsonemus latus infesting Jatropha curcas in Indonesia. Biodiversitas 22: 2648-2655. The broad mite Polyphagotarsonemus latus (Banks) (Acari: Tarsonemidae) has been known to cause a great deal of injury on Jatropha curcas (L.) plantation in Indonesia. Isolation of indigenous fungal entomopathogens from rhizosphere soils, followed by pathogenicity assay was conducted to find an effective isolate for controlling P. latus. Additionally, the potential combination of the selected isolate and soursop (Annona muricata L.) aqueous leaf extract (SLE) was investigated. A total of 24 isolates were obtained by using the insect bait method. Four fungal isolates, namely Paecilomyces sp. 1., Lecanicillium sp., Beauveria sp., and Fusarium sp. 1, showed high conidial viability and were chosen as representatives to assess their pathogenicity against P. latus. Among the tested isolates, Beauveria sp. which had the highest conidial viability among the tested isolates, needed a shorter period to completely kill the tested mites. However, the compatibility test revealed the deleterious effect of SLE on Beauveria sp. SLE at all concentrations showed a very toxic effect on the fungus, therefore the two must be applied separately. Our results provide useful information on the effectiveness of indigenous entomopathogenic fungi Beauveria sp. and aqueous leaf extract of A. muricata as an alternative tool to control the broad mite P. latus on the J. curcas plantation.

Pongamia oil soap for the management of chilli mite, Polyphagotarsonemus latus Banks and its impact on spider population

Field experiment was conducted to check the efficacy of the pongamia oil soap along with Spiromesifen and Neem oil soap at different concentrations in controlling chilli mite, Polyphagotarsonemus latus and its impact on spider population. Spiromesifen was found effective against chilli mite and showed persistent action in the field, whereas pongamia oil soap reported an immediate control over the pest but its effectiveness declined with time and concentration. Among the botanicals, 3% pongamia oil soap was found effective and was followed by the 2% pongamia oil soap. Pongamia oil soap proved effective against mite up to seven days after the treatment and the effect declined by 14 days after the spray. The botanicals as well as the chemical spiromesifen were found safe to spiders in the field.

First report of Polyphagotarsonemus latus (Banks) in Apaxtleco chili (Capsicum annuum L.) cultivated in greenhouse

Objectives: To generate information about a new host of the Polyphagotarsonemuslatus (Banks) mite, and to understand the damages caused by the cultivation ofApatlexco chili pepper (Capsicum annuum L.) in the northern region of the state ofGuerrero.Design/Methodology/Approach: The identification of the mite was carried out throughtaxonomic keys and the damages caused in vegetative shoots, mature leaves andflower buds were described.Results: The P. latus mite was identified as causing important damage to the crops ofAplaxtleco chili pepper grown in greenhouses in the state of Guerrero, Mexico, and thisis the first report of this mite in the Aplaxtleco chili pepper crop grown in greenhouses inthe state of Guerrero, Mexico.Findings/Conclusions: Economic income is obtained from the cultivation of Aplaxtlecochili peppers, a characteristic crop of the municipality of Aplaxtla, in the northern zone of Guerrero; therefore, knowing the identity of the P. latus mite in the Aplaxtleco chili cropwill help to suggest effective control methods to obtain higher yields.