Popular Article Journal Home: www.bioticainternational.com Article: RT0119 How to cite this article? Biotica Karthik and Kukanur, 2020. Gall Formers across Research [Orders. Research Today 2(5) Spl.: 294-295. [ Today 294 Abstract Vol 2:5 alls are abnormal swellings of plant host tissues produced 295 as a result of mechanical damage or feeding by organisms 2020 Spl. Glike . The present study provides brief information on understanding the basic mechanism behind gall formation and also about various gall forming insects. Total number of gall forming Gall Formers species ranges from 13,000 to 2,11,000 belonging to 24 families across six orders. across Insect Or- Introduction wide range of organisms are capable of inducing a ders variety of abnormal swellings on plant host tissues. G. Sai Karthik1* and Vinod S. Kukanur2 AThese swellings are termed as galls resulting from mechanical damage and salivary secretions that initiate increased production of plant growth hormones. Gall 1*Dept. of Entomology, Prof. Jayashankar Telangana State formation is brought by increasing cell size (hypertrophy) and/ Agricultural University, Hyderabad, Telangana (500 030), India or cell number (hyperplasia). All plant organs are amenable to 2International Crops Research Institute for Semi-Arid Tropics, galling. Galls act as physiological sinks providing insects with Hyderabad, Telangana (502 324), India essential resources needed for their growth and development. Gall producers have the power of manipulating the host’s machinery in their favour. Gall-forming insects belong to six orders distributed across 24 families of which two families (Cecidomyiidae: the gall midges, and Cynipidae: the gall ) are exclusively gall makers. The total estimated number of species ranges from 13,000 to 2,11,000. Open Access Homoptera all forming homopterans belongs to Cercopidae Corresponding Author (spittlebug), some Coccoidea, aphids (Aphididae G. Sai Karthik and Phylloxeridae). Aphididae includes gall-formers e-mail: [email protected] G (Eriosomatidae) and free feeding aphids. Phylloxeridae includes former Chermidae and Phylloxeridae. Keywords Chermidae: They feed exclusively on conifer hosts. Not all Galls, Insects, Diptera, Homoptera. species are gall formers. E.g.: Eastern spruce gall aphid. Phylloxeridae: They feed and form galls on deciduous trees. These galls are characterized by an opening, usually surrounded by hairy lobes. Eriosomatidae: Alternation of hosts is present where overwintering eggs are deposited on the primary host which is a tree and the secondary host is usually an herbaceous Article History plant, on which galls are not usually produced. Some other Received in 10th May 2020 gall producing hemipteran families include Tingidae Adelgidae, Received in revised form 15th May 2020 Asterolecaniidae, Cicadellidae, Coccidae, Diaspididae, Accepted in final form 16th May 2020 Eriococcidae, Kermidae and Psyllidae (Schick et al., 2009). Diptera ost of the gall forming insects belongs to the Diptera. They are tiny, mosquito like flies. The Cecidomyiidae E-mail: [email protected] M(gall midges) comprises of 5000 species, many of © 2020 294 Karthik and Kukanur, 2020

which are gall-formers. They are polyphagous whose larvae Cosmopterigidae, Gelechiidae, Lycaenidae, Pterophoridae, are characterized by a sclerotized structure called spatula and Tortricidae of Lepidoptera and thrips. They form mostly forms the galls whereas adult midges never form the galls. fusiform galls on stems and petiole. Gall formation is a result Examples include Sesamum gall fly (Asphondylia sesami), of rolling, folding of leaves and buds. Coccinia gall fly (Lasiptera falcata), Chilli blossom midge Another group of organisms called mites (Acarina) also form (Asphondylia capsici), Pine needle gall midge (Cecidomyia galls. These tiny mites over winter on their host plant and pinirigidae). Other dipteran families include Anthomyzidae, begin their feeding in spring using their piercing and sucking Chloropidae, Platypezidae and Tephritidae. mouth parts. Tarsonemidae and eriophyidae are the two major gall forming mites. Over 500 species of gall-forming mites have been described, primarily in the genus Eriophyes all-forming species occur in the Tenthredinoidea but also in the Phyllocoptes, Anthocoptes, Oxypleurites, and (), (gall wasps), and Chalcidoidea Epitremerus. Common galls caused by eriophyid mites include G(chalcids). Many of the gall forming erineum or velvet galls on pongamia, ash flower gall, maple (e.g., Pontania desmodioides, P. californica, and P. pisum) bladder gall etc (Schick et al., 2009). form large, fleshy, hollow galls on leaves of several species, particularly willows. Gall wasps are generally found on oak Conclusion and rose. Species may be parthenogenetic or may alternate nsect galls cause huge losses globally in wide range between parthenogenetic and bisexual generations. Examples of plants. It is important to know the vast diversity of include jumping oak gall, oak apple gall, oak bullet gall, and insect gall formers to estimate their losses and framing stem galls on rose. Gall-forming chalcids are minute insects I management strategies. which represent only a small portion of the chalcid group and are mostly entomophagous parasitoids. Other gall forming Reference hymenopteran families include , , Schick, K.N., Dahlsten, D.L., 2009. Gallmaking and insects. (Schick et al., 2009). In Encyclopedia of insects (pp. 404-406). Academic Press. Many other insect groups have species that induce galls but are of minor importance. They include Cerambycidae, Buprestidae and Curculionidae of Coleoptera, Aegeriidae,

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