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The study aimed to verify the identity of Thrips hawaiiensis (Morgan, 1913) (Thripidae: Thysanoptera) based on mitochondrial cytochrome C oxidase I marker and determine its seasonal abundance on Gran Naine, Tall Williams, and GCTCV-218 Cavendish banana plantations in Panabo City, B.E. Dujali, and Carmen in Davao del Norte, Philippines. Fifteen (15) flowering/fruiting plants per cultivar per plantation were selected. The survey was conducted on 11–29 Aug 2020, 14–26 Nov 2020, 08–18 Mar 2021, and 11–25 May 2021. Thrips were sampled from bunches consisting of flowers and fruits by the shaking/tapping method. Temperature and rainfall data were obtained from PAGASA. All thrips samples had a significant match with T. hawaiiensis (GenBank KX233567.1) having 100% query cover with 99.39–99.70% nucleotide identity. Female thrips were dominant on all Cavendish cultivars and in the dry season, their counts doubled, whereas male thrips counts increased more than five times. Analysis of variance between the mean numbers of thrips showed no significant difference among cultivars during the dry and wet seasons (p < 0.05). There was a significant difference between mean counts of female and first instar larvae but no significant difference between the mean counts of female, male, and second instar larvae in Panabo City; whereas in B. E. Dujali, and Carmen, there was a significant difference between the mean numbers of female, male, and first and second instar larvae but no significant difference between the mean numbers of male and first and second instar larvae (p < 0.05). Regression analysis showed that thrips abundance was slightly affected positively by maximum average temperature and seemingly not affected by rainfall.

New records of scarab pests of cacao (Theobroma cacao L.) were reported in the Philippines: the rhizotrogine chafer, Holotrichia bipunctata Brenske, 1892 (Coleoptera: Scarabaeidae: Melolonthinae: Rhizotrogini) and diplotaxine chafer Apogonia palawana Heller, 1897 (Coleoptera: Scarabaeidae: Melolonthinae: Diplotaxini). The feeding patterns of the two insect pests are characterized, and some integrated pest management recommendations were cited.

Papilio chikae and P. hermeli are two endemic swallowtail butterflies in the Philippines found primarily in the Cordillera region and Mindoro Island, respectively. Their species status is still subject to debate due to opposing interpretations of their genitalia and morphological traits. This study aims to delineate these taxa through the use of mitochondrial cytochrome C oxidase subunit I(COI) gene marker, with additional information on their cytochrome C oxidase subunit II(COII) gene. The COI nucleotide sequences from our Philippine P. chikae samples were surprisingly identical to P. hermeliEF514465.1 on the GenBank, whereas our P. hermelisamples showed a 100% similarity with P. hermeliEF514464.1.Based on our phylogenetic analysis, P. chikae and P. hermeli exhibit distinct COI barcodes supported by a high bootstrap value (85%). The P. hermeli voucher specimen with GenBank Acc. No. EF514465.1 clustered with our P. chikae samples, separate from the cluster containing our P. hermelispecimens. Nonetheless, the 3.1–3.4% genetic distance observed in the COI region supported by the formation of two separate clusters suggests species status for these taxa. Moreover, species-specific molecular markers obtained from the COII region displayed a 2.4% distance between these two taxa. These molecular markers could therefore be utilized to distinguish P. chikae from P. hermeli. Nevertheless, a thorough examination of their morphology, behavior, and ecology is still imperative to firmly establish their taxonomic status.

The mitochondrial cytochrome c oxidase subunit 1 (COI) nucleotide sequences of Unaspis mabilis Lit & Barbecho (Hemiptera: Diaspididae), are provided for the first time. The total genomic DNA of each scale insect was extracted from individuals infesting lanzones leaves from three selected sites in Los Baños, Laguna. A partial COI gene amplicon with approximately 750 bp was obtained using the primer pair PcoF1 and LepR1. Nucleotide sequence alignment showed no variation among the COI sequences from all the samples. BLASTn search yielded no significant match with any of the available sequences for Unaspis species. The closest hit was Aulacaspis tubercularis Newstead (GenBank Accession No. HM474091) with 87.4% nucleotide similarity. Nonetheless, phylogenetic analyses revealed that generated COI sequences from U. mabilis form a monophyletic clade with U. yanonensis and U. euonymi, with closer proximity to the former. These findings also strengthen the species status of U. mabilis under the genus Unaspis. The DNA barcodes generated from this study (GenBank Acc. Nos. MN114099, MN14101, and MN114102), could, therefore, be used to verify the species identity of other lanzones scale accessions, as well as monitor the distribution and spread of U. mabilis, which would greatly influence possible pest management options. KEYWORDS: cytochrome C oxidase I, COI, Lansium domesticum Correa, lanzones

A putative nucleopolyhedrovirus (NPV) from a field-collected local Spodoptera picta population was isolated for the first time. Its pathogenesis was described in S. picta larvae and was tentatively assigned the name Spodoptera picta nucleopolyhedrovirus or SppiNPV. With the objective of utilizing this SppiNPV as a biological control agent, its cross-infectivity to S. litura – a very important agricultural pest in the country – was evaluated. Third instar S. litura larvae were infected with approximately 100 occlusion bodies (OBs) of SppiNPV using artificial diet- incorporation. SppiNPV infection in S. litura was clearly observed as the 4th instar larvae exhibited pinkish coloration, a characteristic sign of NPV-infection. In addition, the integument of the mildly-infected larvae easily twisted when touched and often expelled slimy fluid from their mouth. At the advanced stage of infection, larvae became extremely fragile resulting in cuticles that were easily ruptured. At 6 d post-infection (dpi), 20% mortality was observed in the SppiNPV-treated S. litura. At 16 dpi, all the cutworms in the control set-up emerged as normal adults, while only three cutworms (10%) in the NPV-treated larvae emerged as adults but with short malformed wings and abnormally soft and fragile abdomen. The effect of SppiNPV on the weight gain of S. litura larvae was also monitored at 4 and 6 dpi. Although significantly higher weight (F = 5.09; df = 58; P > 0.0278) was recorded in the untreated cutworms than the NPV-treated cutworms at 4 dpi, weight gain did not significantly differ in SppiNPV-infected and untreated larvae. Overall, a significantly higher mortality of 46.67% (F = 25.37; df = 58; P > 0.0001) was recorded in SppiNPV-infected cutworm larvae. Further studies to characterize this novel SppiNPV, increase its virulence to S. litura through the continuous passage in S. litura, and optimize the amount of OB to be applied to ensure 100% mortality are recommended so that it can be used as a biological control agent with expanded host range.