G. T. Behere

A Brave New World for an Old World Pest: Helicoverpa armigera (Lepidoptera: Noctuidae) in Brazil

The highly polyphagous Old World cotton bollworm Helicoverpa armigera is a quarantine agricultural pest for the American continents. Historically H. armigera is thought to have colonised the American continents around 1.5 to 2 million years ago, leading to the current H. zea populations on the American continents. The relatively recent species divergence history is evident in mating compatibility between H. zea and H. armigera under laboratory conditions. Despite periodic interceptions of H. armigera into North America, this pest species is not believed to have successfully established significant populations on either continent. In this study, we provide molecular evidence via mitochondrial DNA (mtDNA) cytochrome oxidase I (COI) and cytochrome b (Cyt b) partial gene sequences for the successful recent incursion of H. armigera into the New World, with individuals being detected at two sites (Primavera do Leste, Pedra Preta) within the State of Mato Grosso in Brazil. The mtDNA COI and Cyt b haplotypes detected in the Brazilian H. armigera individuals are common throughout the Old World, thus precluding identification of the founder populations. Combining the two partial mtDNA gene sequences showed that at least two matrilines are present in Brazil, while the inclusion of three nuclear DNA Exon-Primed Intron-Crossing (EPIC) markers identified a further two possible matrilines in our samples. The economic, biosecurity, resistance management, ecological and evolutionary implications of this incursion are discussed in relation to the current agricultural practices in the Americas.

Host Plants Alter the Reproductive Behavior of Pieris brassicae Lepidoptera Pieridae and its Solitary Larval Endo-Parasitoid, Hyposoter ebeninus Hymenoptera Ichneumonidae in a Cruciferous Ecosystem

ABSTRACT The behavior of most destructive pest of cabbage, Pieris brassicae and that of its potential parasitoid, Hyposoter ebeninus, were studied under the influence of 4 common Brassica host plantspecies, cabbage, broccoli, cauliflower and knol-kohl. These host plant species were found to have considerable influence on egg distribution and leaf surface preference for oviposition and pupation. The number of egg masses was highest on knol-khol; however, the number of eggs per mass was highest on cabbage. Similarly, larval incidence was also highest on cabbage throughout the season, indicating that cabbage is the most preferred host. Natural parasitism on P. brassicae larvae by Hyposoter ebeninus was higher on knol-khol and cabbage. The weight of the third instar parasitized caterpillars was the highest on cabbage, suggesting that cabbage is the most favorable of these 4 hosts of P. brassicae for mass rearing of H. ebeninus. The development time of H. ebeninus was also shortest for cabbagereared larvae. Also the cocoon weight of the parasitoid was significantly higher when its host larvae were reared on cabbage. Overall from this study it can be concluded that, of the host plants evaluated, cabbage was preferred for oviposition by P. brassicae and its parasitoid. In addition, cabbage was found to be the best host plant for producing excellent quality H. ebeninus parasitoids.

First Report of Elephant Beetles in the Genus Xylotrupes Hope (Coleoptera: Scarabaeidae) Attacking Guava

Guava, Psidium guajava (L.) (Myrtaceae), is the fourth most intensely cultivated tree fruit on the Indian subcontinent (Chandy 2002). Guava is exceptionally hardy, and even on marginal lands it bears marketable fruit with high vitamin C content and maintains for its producers an attractive income versus investment profile (Singh 2010). In India, guava is cultivated on about 205,000 hectares which yield about 2,500 metric tons per annum (Anonymous 2011). The subtropical climatic conditions of the northeastern Indian state of Meghalaya generate a single, relatively well defined guava fruiting and harvest cycle. During April and May, guava produces its flowers and then fruits in September to October. A large number of insect pests have been reported to occur on guava, but only a few of those reported are known to constitute a significant impediment to the successful cultivation of this crop (Shylesha et al. 2000; Firake et al. 2013). Recently, adult specimens of the elephant beetle genus Xylotrupes Hope were found feeding on the flesh of guava fruits in Meghalaya (Fig. 1), causing considerable losses in yield (35–45%). Furthermore, the often minimal damage inflicted by these beetles on the mature fruits can predispose the fruits to secondary attack by other insects (Fig. 2) and pathogens, all of which can augment market losses. On occasion, up to 98% of fruit can be damaged by Xylotrupes. Three male specimens of Xylotrupes from Meghalaya were sequenced at the 5′ region of the COI gene (NCBI Accession No: KF494189) and these sequences were found by Jen-Pan Huang, University of Michigan (personal communication) to nest within an unpublished, large series of specimens sequenced at the same region of COI gene. The latter series was assembled from diverse localities across Southeast Asia and had been previously identified as Xylotrupes siamensis Minck by criteria in Rowland (2003, 2011). According to the latter evidence, the identity of the Xylotrupes beetles found attacking guava in Meghalaya is here assigned as X. siamensis. Xylotrupes siamensis is reddish brown to black in color and 30–40 mm in body length. The males bear cephalic and pronotal horns, and the females are smaller and do not bear horns (Endrödi 1985; Waite and Elder 2000). The genus Xylotrupes is one of the most widespread genera of large beetles in the world. Its natural distribution extends over nearly a third of the earth’s circumference from the high valleys of Himalayan Pakistan east and south into India, Southeast Asia, China, the Malay Archipelago, Australasia into Melanesia as far as Vanuatu in the South Pacific (CAB International 2002; Rowland 2003, 2011, in Foreword in Hwang 2011). Xylotrupes beetles are known to be polyphagous, feeding on bark, fruits, panicles, and inflorescences of a large number of host plants viz., Acacia mearnsii De Wild (Fabaceae), Toona australis Kuntz (Meliaceae), pineapple, longan, lychee (Waite and Elder 2000), bamboo, coconut, cashewnut, cinnamon, African oil palm, rubber, banana, plantain, sugarcane, potato (CAB International 2002), passion fruit (Shylesha and Rao 2004), maize, sword bean (Shylesha et al. 2006), okra (Nair et al. 2001), poinciana, gulmohar, cacao, and som (Eswarareddy and Rajan 2011). To our knowledge, infestation or management of Xylotrupes beetles on guava has not been previously reported. For this reason, we have initiated studies based upon quantifiable variables associated with feeding by X. siamensis on guava fruit in the orchards of our experimental farm in Meghalaya, so that feasible

Rapid Technique of Sex Differentiation in Immature Stage of a Parasitoid Wasp, Hyposoter Ebeninus Gravenhorst (Hymenoptera: Ichneumonidae)

ABSTRACT: Parasitoid populations having optimum male: female ratios are generally released in the field during the cocoon stage for an effective bio-control program. Due to the distinctive habit of forming a cocoon within the shrunken larval body of the host, cocoons of both sexes of the icheneumonid wasp, Hyposoter ebeninus, displayed morphological similarities. Therefore, male and female cocoons cannot be differentiated based on normal morphological parameters. In this report, we tested several combinations of morphological parameters and size indices and developed a simple technique for separation of sexes at the cocoon stage of this wasp. Among ten possible parameters tested, the weight of the cocoon was found to be the most appropriate and reliable parameter for sex separation with a 100% success rate. Since this technique involves only one parameter, it is simple, robust and requires minimum technical skill. This technique would be very useful for research workers, commercial biological control laboratories and other related agencies working on H. ebeninus.

Genetic characterization of Bactrocera fruit flies (Diptera: Tephritidae) from Northeastern India based on DNA barcodes

Abstract The Northeastern region of India, one of the mega biodiversity hot spots has enormous potential for the production of fruits and vegetables. Fruit flies of the genus Bactrocera Macquart are important pests of fruits and vegetables, and one of the limiting factors in successful production of these commodities. The relationship among some of the species is unclear due to their high molecular and morphological similarities. Moreover, due to the significant morphological resemblance between fruit fly species, reliable identification is very difficult task. We genetically characterized 10 fruit fly species of the genus Bactrocera by using standard DNA barcoding region of COI gene. The characterization and identification of eight species were straight forward. This study was unable to establish the molecular identity of Bactrocera sp. 2. Within the 547 bp region of partial COI gene, there were 157 variable sites of which 110 sites were parsimony informative, 153 were synonymous substitutions and 4 were non-synonymous substitutions. The estimate of genetic divergence among the ten species was in the range of 0–21.9% and the pairwise genetic distance of Bactrocera. (Bactrocera) dorsalis (Hendel) with B. (B.) carambolae was only 0.7%. Phylogenetic analysis formed separate clades for fruit and vegetable infesting fruit flies. B. (B.) aethriobasis Hardy, B. (B.) thailandica and B. (B.) tuberculata (Bezzi) have been reported for the first time from the Northeastern India. The information generated from this study would certainly have implications for pest management, taxonomy, quarantine and trade.

First Report of the Mealybug Formicococcus polysperes (Hemiptera: Pseudococcidae) Infesting Ginger in India

ABSTRACT: The mealybug Formicococcus polysperes Williams (Hemiptera: Pseudococcidae) is here reported for the first time attacking ginger rhizomes (Zingiber officinale Roscoe (Zingiberaceae)) in Meghalaya State of India. Plants infested by the sap-sucking nymphs and adults of this mealybug turned yellow within 1 to 2 weeks and then started drying from the tip downwards. Infested rhizomes shriveled and eventually dried out. Fields and a nearby storage facility experienced up to 48% crop loss due to the infestation. In this paper we describe the plant damage and the morphological characteristics of F. polysperes from Meghalaya.

First Report of Tiracola plagiata Walker (Lepidoptera: Noctuidae) Attacking Dolichos Bean, Lablab purpureus L. from Meghalaya, India

ABSTRACT: The banana fruit caterpillar, Tiracola plagiata Walker (Lepidoptera: Noctuidae: Hadeninae) is reported for the first time attacking the dolichos bean, Lablab purpureus L. The caterpillars feed on leaves as well as pods and frequently cause severe losses (68–72%). This is a new insect pest observed on dolichos bean plants in the last three years. Therefore, we studied basic biological and some quantifiable parameters associated with the infestation of T. plagiata on bean plants, so that feasible management strategies against this pest can be formulated. In the laboratory, T. plagiata took 81.67±4.41 days to complete its life cycle. Adults were positively phototrophic; therefore light traps could be an effective control option for this pest.

First report of coconut case caterpillar, Mahasena corbetti Tams (Lepidoptera: Psychidae) from India

Coconut case caterpillar or Bagworm, Mahasena corbetti Tams (Lepidoptera: Psychidae), is a destructive polyphagus pest in Southeast Asia and some islands of the Pacific. Considering the rapid expansion of the distribution range of M. corbetti, this species is included in the list of dangerous pests in plant quarantine act of Malaysia. M. corbetti is also considered as a pest of quarantine importance in many countries. During 2015–2016, severe incidence of M. corbetti was observed for the first time on arecanut (Areca catechu L.) plants in Sohbar and adjoining villages of East Khasi Hills district of Meghalaya state (India). This is the first report on occurrence of M. corbetti in India. We are reporting the infestation, natural field parasitism and description of life stages of M. corbetti infesting arecanut plants in India. Considering the taxonomic complexities in identification and destructive nature of bagworms, we have also developed DNA barcode for this species by sequencing standard barcoding region of mitochondrial cytochrome oxidase I (COI) gene. This report would serve as a preliminary foundation for reliable diagnosis of M. corbetti and also for creating awareness among the arecanut growers and other related functionaries in India and nearby countries.