How does the life cycle of Clinodiplosis profusa (Cecidomyiidae) adjust to phenological variations of the host plant Eugenia uniflora (Myrtaceae) in sun and shade?

Galls are plant neoformations induced by specialized parasites. Since gall inducers rely on reactive plant sites for gall development, variations in abiotic factors that affect plant phenology are expected to impact the life cycle of gall inducers. To test the hypothesis that different light conditions affect both host plant and gall inducer life cycles, we studied the system Eugenia uniflora (Myrtaceae) - Clinodiplosis profusa (Cecidomyiidae), comparing plants occurring in sunny and shaded environments. We mapped phenological differences among individuals of E. uniflora occurring in the two environments and related them to the influence of luminosity on the life cycle of the gall inducer. Shade plants showed lower intensity of leaf sprouting throughout the year compared to sun-exposed plants, especially during the rainy season. Young and mature galls are synchronized with the peak of leaf sprouting at the beginning of the rainy season, lasting longer in sun-exposed plants - approximately two months longer compared to shade plants. The greater light intensity positively impacts the formation and growth of leaves and galls, with an extended period available for their induction and growth. Thus, light is an important factor for the development of gallers, considering that variations in luminosity influenced not only the phenology of the host plant, but also determined the life cycle of gall inducers. Furthermore, changes in plant-environment interactions are expected to affect the life cycle and richness of other host plant-gall inducer systems.

First trials exploring the potential of phytoseiid mites in managing lychee erinose mite, Aceria litchii (Keifer) (Acari: Eriophyidae), infestations on lychee plants.

Phytoseiid mites have been frequently found in association with the lychee erinose mite, Aceria litchii, on lychee plants in Brazil, suggesting that they are promising candidates as biological control agents against this pest. Here, we investigated whether phytoseiids would suppress A. litchii infestation, i.e. formation of erinea, on lychee plants under field conditions. Four groups of A. litchii-infested plants were randomly distributed in the field, with each group receiving either Phytoseius intermedius, Amblyseius herbicolus, A. herbicolus supplemented with cattail pollen or no predator. During a three-month period, the released predators, along with others present in the surrounding environment, were allowed to freely walk among all plants. In each plant, we evaluated the occurrence of phytoseiid species, their abundance, and the dynamics of erinea formation. A total of 2,097 mites, including 13 other phytoseiid species were identified. The most abundant species were Iphiseiodes zuluagai and Euseius ho, rather than the two predator species that were released. A. herbicolus and P. intermedius failed to establish populations in the majority of the plants, regardless of the presence of pollen, suggesting their ineffectiveness in controlling A. litchii infestations. While there was a significant difference in the proportion of erinea among the four treatments, this contrast was not associated with the presence of phytoseiids, suggesting that other factors might have hindered erinea formation on lychee plants. The reasons behind this outcome are further explored and discussed.

Microbiome and plant cell transformation trigger insect gall induction in cassava.

Several specialised insects can manipulate normal plant development to induce a highly organised structure known as a gall, which represents one of the most complex interactions between insects and plants. Thus far, the mechanism for insect-induced plant galls has remained elusive. To study the induction mechanism of insect galls, we selected the gall induced by Iatrophobia brasiliensis (Diptera: Cecidomyiidae) in cassava (Euphorbiaceae: Manihot esculenta Crantz) as our model. PCR-based molecular markers and deep metagenomic sequencing data were employed to analyse the gall microbiome and to test the hypothesis that gall cells are genetically transformed by insect vectored bacteria. A shotgun sequencing discrimination approach was implemented to selectively discriminate between foreign DNA and the reference host plant genome. Several known candidate insertion sequences were identified, the most significant being DNA sequences found in bacterial genes related to the transcription regulatory factor CadR, cadmium-transporting ATPase encoded by the cadA gene, nitrate transport permease protein (nrtB gene), and arsenical pump ATPase (arsA gene). In addition, a DNA fragment associated with ubiquitin-like gene E2 was identified as a potential accessory genetic element involved in gall induction mechanism. Furthermore, our results suggest that the increased quality and rapid development of gall tissue are mostly driven by microbiome enrichment and the acquisition of critical endophytes. An initial gall-like structure was experimentally obtained in M. esculenta cultured tissues through inoculation assays using a Rhodococcus bacterial strain that originated from the inducing insect, which we related to the gall induction process. We provide evidence that the modification of the endophytic microbiome and the genetic transformation of plant cells in M. esculenta are two essential requirements for insect-induced gall formation. Based on these findings and having observed the same potential DNA marker in galls from other plant species (ubiquitin-like gene E2), we speculate that bacterially mediated genetic transformation of plant cells may represent a more widespread gall induction mechanism found in nature.

Vascular implications of Dasineura sp. galls' establishment on Peumus boldus stems.

Some chewing larvae are capable of inducing galls in the host vascular cylinder, e.g. Dasineura sp. (Cecidomyiidae) on Peumus boldus stems. Due to the medicinal and economic importance of P. boldus, the anatomical and functional implications of establishment of Dasineura sp. on P. boldus stems were investigated. We asked if establishment of Dasineura sp. in P. boldus stems induces abnormalities at the cellular and organizational level of the vascular system that increase during gall development in favour of the hydric status of the gall. Anatomical alterations induced in the stems during gall development were determined. Cytohistometric analyses in mature galls were compared to non-galled stems, and water potential and leaf area of non-galled stems were compared with galled stems. Dasineura sp. establishes in the vascular cambium, leading to delignification and rupture of xylem cells, inhibiting formation of phloem and perivascular sclerenchyma. Gall diameter increases together with larval feeding activity, producing a large larval chamber and numerous layers of nutritive tissue, vascular parenchyma, and sclerenchyma. These anatomical alterations do not affect the leaf area of galled stems but favour increased water flow towards these stems. The anatomical alterations induced by Dasineura sp. in P. boldus stems guarantee water and nutrient supply to the gall and larva. After the inducer exits stems, some host branches no longer have vascular connections with the plant body.

Population Genetic Analysis of Fusarium decemcellulare, a Guaraná Pathogen, Reveals High Genetic Diversity in the Amazonas State, Brazil.

Guaraná is indigenous to the Brazilian Amazon where it has cultural and agroeconomic significance. However, its cultivation is constrained by a disease termed oversprouting of guaraná caused by Fusarium decemcellulare, with yield losses reaching as high as 100%. The disease can affect different parts of the plant, causing floral hypertrophy and hyperplasia, stem galls, and oversprouting of vegetative buds. To date, no study has been conducted characterizing the genetic diversity and population structure of this pathogen. Here, we report genetic diversity and genetic structure among 224 isolates from eight guaraná production areas of Amazonas State, Brazil, that were genotyped using a set of 10 inter-simple-sequence repeat (ISSR) markers. Despite moderate gene diversity (Hexp = 0.21 to 0.32), genotypic diversity was at or near maximum (223 multilocus genotypes among 224 isolates). Population genetic analysis of the 10 ISSR marker fragments with STRUCTURE software identified two populations designated C1 and C2 within the F. decemcellulare collection from the eight sites. Likewise, UPGMA hierarchical clustering and discriminant analysis of principal components of the strains from guaraná resolved these same two groups. Analysis of molecular variance demonstrated that 71% of genetic diversity occurred within the C1 and C2 populations. A pairwise comparison of sampling sites for both genetic populations revealed that 59 of 66 were differentiated from one another (P < 0.05), and high and significant gene flow was detected only between sampling sites assigned to the same genetic population. The presence of MAT1-1 and MAT1-2 strains, in conjunction with the high genotypic diversity and no significant linkage disequilibrium, suggests that each population of F. decemcellulare might be undergoing sexual reproduction. Isolation by distance was not observed (R2 = 0.02885, P > 0.05), which suggests that human-mediated movement of seedlings may have played a role in shaping the F. decemcellulare genetic structure in Amazonas State, Brazil.

Gall-inducing Eriophyes tiliae stimulates the metabolism of Tilia platyphyllos leaves towards oxidative protection.

Red galls have high levels of anthocyanins which perform different physiological functions, such as antioxidants and protection against UVB radiation. High levels of anthocyanins and other polyphenols have been associated with low photosynthetic pigment content. In environments with high levels of UVB radiation, it would thus be expected that red galls would have high anthocyanin and polyphenol levels and low photosynthetic pigment contents, enabling the gall with high antioxidant capacity compared to its host organ. The red galls induced by Eriophyes tiliae, and their host environment of Tilia platyphyllos leaves in the Mediterranean climate of Chile, were investigated in relation to their anatomy, histochemistry, pigment, sugar, protein, and polyphenol contents, and antioxidant capacity. The anthocyanin, sugars, and polyphenol contents and the antioxidant capacity were increased in galls. Photosynthetic pigment and protein contents were higher in non-galled leaves. The high levels of anthocyanin and total polyphenols increase the galls' antioxidant capacity in the high UV radiation environment of a Mediterranean climate. The establishment of E. tiliae induced redifferentiation of nutritive tissue, rich in sugars, proteins, and lipids, and an inner epidermis with trichomes and long emergences. E. tiliae galls' structural and metabolic features are probably enhanced towards mite nutrition and protection. The current results shed light on the role of anthocyanin in the antioxidant protection of plant galls in environments with high UV irradiance.

Population suppression of phylloxera gallicolae and radicicolae forms on grapevines with the use of synthetic insecticides / Supressão populacional de fase galícola e radícola da filoxera em videira com a utilização de inseticidas sintéticos

The grapevine phylloxera Daktulosphaira vitifoliae (Fitch, 1856) is the main insect pest of viticulture globally. Infestations can occur in the aerial part of the plant (gallicolae form) and roots (radicicolae form). In this study, the effect of insecticides on the populations suppression of the gall and root forms of phylloxera one vine was evaluated. For the gallicolous form, the thiamethoxam (Actara 250 WG®, 40g c.p./100L-1), flupyradifurone (Sivanto® Prime 200 SL, 75mL c.p./100L-1), and sulfoxaflor (Closer® SC, 40mL c.p./100L-1) were evaluated in the field, under natural infestation, using rootstock plants 'Paulsen 1103' (Vitis berlandieri x V. rupestris). For the root stage, an experiment was carried out in a greenhouse using rooted seedlings of 'Cabernet Sauvignon' (Vitis vinifera) grown in pots artificially infested with 200 phylloxera eggs per plant. After 80 days of infestation, the thiamethoxam (0.2g p.c./plant), flupyradifurone (0.8mL p.c./plant), sulfoxaflor (0.3mL/plant) and imidacloprid (Proved 200 SC, 0.7 mL/plant) were applied via drench. For the gallicolae form, an application of the flupyradifurone provided a gall reduction of 90% at 28 days after the first application (DAFA). While for thiamethoxam, 3 applications were needed at weekly intervals to maintain the same level of control. For sulfoxaflor, a second application at 14 DAFA was necessary to provide a level of control above 90%. For the root stage, the insecticides sulfoxaflor and imidacloprid showed the best results, with 96 and 89% of control over nymphs and adults, respectively. The insecticides flupiradifurone and sulfoxaflor are suitable for the chemical control of phylloxera in the vine.

A filoxera-da-videira Daktulosphaira vitifoliae (Fitch, 1856) é o principal inseto-praga da viticultura mundial. As infestações podem ocorrer na parte aérea (forma galícola) e raízes (forma radícola). Neste trabalho foi avaliado o efeito de inseticidas na supressão de populações da forma galícola e radícola da praga em videira. Para a fase galícola, os inseticidas thiamethoxam (Actara 250 WG®, 40g p.c/100L-1), flupiradifurona (Sivanto® Prime 200 SL, 75mL p.c/100L-1) e sulfoxaflor (Closer® SC, 40mL p.c/100L-1) foram avaliados a campo, sob infestação natural, utilizando plantas do porta-enxerto 'Paulsen 1103' (Vitis berlandieri x V. rupestris). Para a fase radícola foi conduzido um experimento em casa-de-vegetação a partir de mudas enraizadas de 'Cabernet Sauvignon' (Vitis vinifera) cultivadas em vasos infestados artificialmente com 200 ovos da filoxera por planta. Após 80 dias da infestação, os inseticidas thiamethoxam (0,2g p.c./planta), flupiradifurona (0,8mL p.c. /planta), sulfoxaflor (0,3mL/planta) e imidacloprido (Provado 200 SC, 0,7 mL/planta) foram aplicados via drench. Para a fase galícola, uma aplicação do inseticida flupiradifurona proporcionou uma redução de galhas de 90% aos 28 dias após a primeira aplicação (DAPA). Enquanto que para o thiamethoxam, foram necessárias três aplicações em intervalos semanais para manter o mesmo nível de controle. Para o sulfoxaflor, foi necessária uma segunda aplicação aos 14 DAPA, para proporcionar um nível de controle acima de 90%. Para a fase radícola, os inseticidas sulfoxaflor e imidacloprido apresentaram os melhores resultados, com 96 e 89% de controle sobre ninfas e adultos respectivamente. Os inseticidas flupiradifurona e sulfoxaflor são alternativas aos neonicotinoides (imidacloprido e thiametoxam) para a supressão populacional da filoxera na cultura da videira.

Occurrence and characterization of insect galls in two reserves of the Peruvian Amazon / Ocorrência e caracterização de galhas de insetos em duas reservas da Amazônia peruana

Abstract An insect gall inventory was carried out in two reserves of the Peruvian Amazon, Allpahuayo-Mishana National Reserve and Quistococha Regional Reserve, both situated in Iquitos, northeastern Peru. Four vegetation types were surveyed between December, 2021 and December, 2022: terra firme forest, white-sand wet forest, and white-sand dry forest in Allpahuayo-Mishana National Reserve, and palm swamp forest in Quistococha Regional Reserve. Overall, we found 262 gall morphotypes, distributed across 75 host species representing 66 plant genera and 30 families. Fabaceae was the plant family with the greatest number of gall morphotypes (n = 48), followed by Calophyllaceae (n = 21) and Euphorbiaceae (n = 20). The plant genera that supported the highest diversity of galls were Caraipa (n = 17), Eschweilera (n = 16), Tapirira (n = 16), Micrandra (n = 14), and Iryanthera (n = 10). The plant species Tapirira guianensis (n = 16), Caraipa utilis (n = 14), Micrandra elata (n = 14), Eschweilera coriacea (n = 11), and Sloanea parvifructa (n = 10) exhibited the highest richness of galls. Among the host plants, C. utilis stands alone as the only species noted as both endemic to the Amazonian region and bearing a Vulnerable (VU) conservation status. The leaves were the most attacked organs (90% of all galls). Most morphotypes are glabrous (89%), green (67%), globoid (53%), and one-chambered (91%). We found galling insects belonging to the orders Diptera, Thysanoptera, Lepidoptera, and Hemiptera. The galling insects of Cecidomyiidae (Diptera) were the most common, inducing 22% of the gall morphotypes. In addition to the gallers, we also observed the presence of successors, cecidophages, and parasitoids. Among the sampled vegetation types, the terra firme forest presented the highest richness of gall morphotypes and host plant species. This is the first systematic inventory of insect galls in this part of the Peruvian Amazon.

Resumo Um inventário de galhas de insetos foi realizado em duas reservas da Amazônia peruana, Reserva Nacional Allpahuayo-Mishana e Reserva Regional Quistococha, ambas situadas em Iquitos, nordeste do Peru. Quatro tipos de vegetação foram pesquisados entre dezembro de 2021 e dezembro de 2022: floresta de terra firme, floresta úmida de areia branca e floresta seca de areia branca na Reserva Nacional Allpahuayo-Mishana, e floresta de pântano de palmeiras na Reserva Regional Quistococha. No total, encontramos 262 morfotipos de galhas, distribuídos em 75 espécies hospedeiras representando 66 gêneros de plantas e 30 famílias. Fabaceae foi a família de plantas com o maior número de morfotipos de galhas (n = 48), seguida por Calophyllaceae (n = 21) e Euphorbiaceae (n = 20). Os gêneros de plantas que apresentaram a maior diversidade de galhas foram Caraipa (n = 17), Eschweilera (n = 16), Tapirira (n = 16), Micrandra (n = 14) e Iryanthera (n = 10). As espécies de plantas Tapirira guianensis (n = 16), Caraipa utilis (n = 14), Micrandra elata (n = 14), Eschweilera coriacea (n = 11) e Sloanea parvifructa (n = 10) apresentaram a maior riqueza de galhas. Dentre as plantas hospedeiras, C. utilis destaca-se como a única espécie listada como endêmica da região amazônica e com um status de conservação Vulnerável (VU). As folhas foram os órgãos mais atacados (90% de todas as galhas). A maioria dos morfotipos é glabra (89%), verde (67%), globoide (53%) e possui apenas uma câmara interna (91%). Encontramos insetos galhadores pertencentes às ordens Diptera, Thysanoptera, Lepidoptera e Hemiptera. Os insetos galhadores da família Cecidomyiidae (Diptera) foram os mais comuns, induzindo 22% dos morfotipos de galhas. Além dos galhadores, também observamos a presença de sucessores, cecidófagos e parasitoides. Entre os tipos de vegetação amostrados, a floresta de terra firme apresentou a maior riqueza de morfotipos de galhas e espécies de plantas hospedeiras. Este é o primeiro inventário sistemático de galhas de insetos nesta região da Amazônia peruana.

Entomogenous galls and their associated fauna in deciduous dry forest and woodland vegetation remnants (Caatinga) in the Northern Depressão Sertaneja, Brazil / Galhas entomógenas e sua fauna associada em remanescentes de floresta seca e vegetação lenhosa decídua (Caatinga) na Depressão Sertaneja Setentrional, Brasil

Abstract A survey and characterization of entomogenous galls and their associated fauna were carried out in six remnants of Caatinga in the Northern Depressão Sertaneja, in the states of Paraíba, Rio Grande do Norte and Ceará. We identified 41 gall morphotypes in 24 plant species, belonging to 12 botanical families. Fabaceae had 29.2% (n = 12) of the total number of gall morphotypes found. Leaves (61%) and stems (25%) were the most attacked organs. Most morphotypes are glabrous (75.6%), while only 24.4% exhibit trichomes. Most galls were induced by insects of the Cecidomyiidae family. The associated fauna comprised successors, cecidophages, tenants, and parasitoids. Sucessors were found in four morphotypes of galls and included spiders and four orders of insects: Hemiptera, Coleoptera, Lepidoptera, and Hymenoptera (Formicidae). The tenants were represented by Tanaostigmoides (Tanaostigmatidae). The parasitoids, found in 18 morphotypes (43.9%), were represented by six families of Hymenoptera. We recorded the occurrence of new types of galls in 12 species of host plants. These gall records are new references for the Northern Depressão Sertaneja in the studied states.

Resumo Realizou-se um levantamento e caracterização de galhas entomógenas e sua fauna associada em seis remanescentes de Caatinga presentes na Depressão Sertaneja Setentrional nos estados da Paraíba, Rio Grande do Norte e Ceará. Identificamos 41 morfotipos de galhas em 24 espécies de plantas, pertencentes a 12 famílias botânicas. Fabaceae abrigou 29,2% (n = 12) do total de morfotipos de galhas encontrados. As folhas (61%) e os caules (25%) foram os órgãos mais atacados. A maioria dos morfotipos é glabra (75,6%), enquanto apenas 24,4% exibiram tricomas. As galhas, em sua maioria, foram induzidas por insetos da família Cecidomyiidae. A fauna associada compreendeu sucessores, fungívoros, inquilinos e parasitoides. Os primeiros foram encontrados em quatro morfotipos de galhas, estando representados por aranhas e quatro ordens de insetos: Hemiptera, Coleoptera, Lepidoptera e Hymenoptera (Formicidae). Os inquilinos foram representados por Tanaostigmoides Ashmead, 1896 (Tanaostigmatidae). Já os parasitoides, encontrados em 18 morfotipos de galhas (43,9%), foram representados por seis famílias de Hymenoptera. Registramos a ocorrência de novos tipos de galhas em 12 espécies de plantas hospedeiras. Os registros de galhas também são novas referências para a Depressão Sertaneja Setentrional nos estados estudados.

Anatomical profiles validate gall morphospecies under similar morphotypes.

Plant galls are generated by the stimuli of gall-inducing organisms on their hosts, creating gall morphotypes that vary in color, shape, size, and tissue organization. Herein, we propose to compare the structural features of gall morphotypes on the superhost Croton floribundus (Euphorbiaceae) in order to recognize gall morphospecies, i.e., galls with similar shapes but different internal structures. Non-galled leaves and galls were analyzed macroscopically, histologically, and histochemically for the detection of primary metabolites, and the results obtained were used for statistical analyses of similarity. Among the eight gall morphospecies, four are globoid, two are lenticular, one is fusiform and one is marginal leaf rolling. Stomatal differentiation and the occurrence of different types of trichomes were impaired in some gall morphospecies. Three patterns of organization of the ground system are recognized, ranging from the maintenance of mesophyll cells that differentiate into palisade and spongy cells dorsiventrally to the formation of a complex cortex with three morphofunctional layers. The marginal leaf rolling galls have the simplest anatomical structures, quite similar to those of the non-galled host leaf, while lenticular, globoid (types I to IV), and fusiform galls are anatomically more complex. Herein, we report on eight gall morphospecies occurring on C. floribundus, which are distinguished by morpho-anatomical attributes and show the disruption of the morphogenetic patterns of the host leaf toward the morphogenesis of unique gall features.

Subtle structures with not-so-subtle functions: A data set of arthropod constructs and their host plants.

The construction of shelters on plants by arthropods might influence other organisms via changes in colonization, community richness, species composition, and functionality. Arthropods, including beetles, caterpillars, sawflies, spiders, and wasps often interact with host plants via the construction of shelters, building a variety of structures such as leaf ties, tents, rolls, and bags; leaf and stem galls, and hollowed out stems. Such constructs might have both an adaptive value in terms of protection (i.e., serve as shelters) but may also exert a strong influence on terrestrial community diversity in the engineered and neighboring hosts via colonization by secondary occupants. Although different traits of the host plant (e.g., physical, chemical, and architectural features) may affect the potential for ecosystem engineering by insects, such effects have been, to a certain degree, overlooked. Further analyses of how plant traits affect the occurrence of shelters may therefore enrich our understanding of the organizing principles of plant-based communities. This data set includes more than 1000 unique records of ecosystem engineering by arthropods, in the form of structures built on plants. All records have been published in the literature, and span both natural structures (91% of the records) and structures artificially created by researchers (9% of the records). The data were gathered between 1932 and 2021, across more than 50 countries and several ecosystems, ranging from polar to tropical zones. In addition to data on host plants and engineers, we aggregated data on the type of constructs and the identity of inquilines using these structures. This data set highlights the importance of these subtle structures for the organization of terrestrial arthropod communities, enabling hypotheses testing in ecological studies addressing ecosystem engineering and facilitation mediated by constructs. There are no copyright restrictions and please cite this paper when using the data in publications.

Complex meristematic activity induced by Eucecidoses minutanus on Schinus engleri turns shoots into galls.

PREMISE: Gall-inducing organisms change the development of their host plant organs, resulting in ontogenetic patterns not observed in the non-galled plants. Distinct taxa induce galls on Schinus spp., manipulating meristematic patterns in the host plant in distinct ways. Here we report ontogenetic novelties induced in the lateral buds of S. engleri by Eucecidoses minutanus, a Cecidosidae, whose galls have been poorly understood. METHODS: The anatomy, histochemistry, and histometry of galls in distinct phases of development, non-galled buds, and stems of Schinus engleri were analyzed in parallel with the instars of E. minutanus to detail the morphogenetic changes in the host with each larval stage. RESULTS: Ontogenetic phases of the galls were intricately associated with larval development. First and second-instar larvae induced pericycle and pith cells to dedifferentiate into the gall inner meristem, where hyperplasia and cell hypertrophy characterized the growth and development phase of the gall. The innermost layers were lipid-rich nutritive cells that lined the larval chamber. Additional vascular bundle rows were produced in young galls. Third and fourth instar-larvae were associated with the gall maturation phase: centripetal lignification of the outer parenchyma cell layers, epidermal stratification, and activation of a cambium-like meristem (CLM). The CLM activity resulted in new layers of nutritive cells that differentiated inward as the first layers of nutritive cells were consumed by E. minutanus larvae, and, also, in more parenchyma cell layers that formed outward. All tissues between the innermost layer of nutritive tissue that surround the gall chamber and the outermost layer of the dermal system that externally covers the gall form the gall wall, and increased in thickness until the end of gall maturation. CONCLUSIONS: E. minutanus induces a structurally complex globoid stem gall, modifying all host plant tissues and stimulating a novel meristematic pattern in S. engleri. The gall developmental stages are each related to specific gall-inducing instars, as gall development progresses according to the development of E. minutanus.

Structural and Nutritional Peculiarities Related to Lifespan Differences on Four Lopesia Induced Bivalve-Shaped Galls on the Single Super-Host Mimosa gemmulata.

Super-host plants are elegant models to evaluate the peculiarities of gall structural and nutritional profiles due to the stimuli of distinct gall inducers in temporal and spatial perspectives. Galls induced by congeneric insects, Lopesia spp. (Diptera, Cecidomyiidae) on the same host plant, Mimosa gemmulata Barneby (Fabaceae) were analyzed to estimate if variations of 1 or 2 months in gall lifespans may result in differences over the accumulation of nutritional resources, and their compartmentalization both in cell walls and protoplasm. Mimosa gemmulata hosts four Lopesia-induced galls: the lenticular bivalve-shaped gall (LG) with a 2-month life cycle, the brown lanceolate bivalve-shaped gall (BLG) and the green lanceolate bivalve-shaped gall (GLG) with 3 month-life cycles, and the globoid bivalve-shaped gall (GG) with a 4 month-life cycle. The comparisons among the four Lopesia galls, using anatomical, histometric, histochemical, and immunocytochemical tools, have demonstrated that the longest lifespan of the GG related to its highest increment in structural and nutritional traits compared with the LG, GLG, and BLG. The differences among the tissue stratification and cell wall thickness of the galls with the 2-month and the 3-month lifespans were subtle. However, the GG had thicker cell walls and higher stratification of the common storage tissue, schlerenchymatic layers and typical nutritive tissue than the other three gall morphospecies. The higher tissue thickness of the GG was followed by the formation of a bidirectional gradient of carbohydrates in the protoplasm, and the detection of xyloglucans in cell walls. Current data supported the presumption that the longest the lifespan, the highest the impact over the structural and nutritional metabolism of the Lopesia galls associated to M. gemmulata.

A compilation of host plants and their gall-inducing insects for the Caatinga Biome / Uma compilação de plantas hospedeiras e seus insetos galhadores para o bioma Caatinga

Caatinga is a seasonally dry tropical forest, one of the richest in plant species. Unfortunately, many groups of herbivorous insects associated with these plants are poorly known. This study aimed to investigate the diversity of gall-inducing insects (GII) and host plants (HP) in the Caatinga. For this, we compiled the information available in the literature of inventories on GII and their HP communities, and the described gall midge species. We found 100 species, 72 genera, and 32 families of HP hosting a total of 156 morphospecies of GII and 12 species of described cecidomyiids. Plant species with only one GII species represented 74% of hosts, but in super HP (i.e., HP with a high number of GII), despite the small number of HP species, there were many GII species. Fabaceae was also the most specious family, with 30% of HP species and 40% of GII. Furthermore, our results showed a low number of species of HP and GII for the Brazilian Caatinga, that we discussed this pattern with the following arguments, first, it is likely that the number of galling insect inventories for the Caatinga is under-sampled, second the Caatinga has a relatively smaller number of plant species when compared to other biomes, and finally, we argue that the Caatinga is a seasonally dry tropical forest where the deciduousness represents a relevant factor in the colonization and performance rates of GII.

A Caatinga é uma floresta tropical sazonalmente seca, uma das mais ricas em espécies vegetais. Infelizmente, muitos grupos de insetos herbívoros associados a essas plantas são pouco conhecidos. Este estudo teve como objetivo investigar a diversidade de insetos galhadores (IG) e plantas hospedeiras (PH) na Caatinga. Para isso, nós compilamos as informações disponíveis na literatura de inventários sobre a comunidade de IG e suas PH, e as espécies descritas de cecidomiídeos. Nós encontramos 100 espécies, 72 gêneros e 32 famílias de PH abrigando um total de 156 morfoespécies de IG e 12 espécies descritas de cecidomiídeos. Espécies de plantas com apenas uma espécie de IG representaram 74% das hospedeiras, mas para as super PH (ou seja, PH com alto número de IG), apesar do pequeno número de espécies de PH, havia muitas espécies de IG. Fabaceae foi a família mais rica, com 30% das espécies de PH e 40% dos IG. Além disso, nossos resultados mostraram um baixo número de espécies de PH e IG para a Caatinga brasileira, e discutimos esse padrão com os seguintes argumentos, primeiro, é provável que o número de inventários de insetos galhadores para a Caatinga seja subamostrado, segundo a Caatinga possui um número relativamente menor de espécies vegetais quando comparada a outros biomas e, por fim, argumentamos que a Caatinga é uma floresta tropical sazonalmente seca onde a deciduidade representa um fator relevante para as taxas de colonização e desempenho dos IG.

Apoplast-symplast compartmentalization and functional traits of iron and aluminum in promeristematic tissues of nematode induced galls on Miconia spp.

The nutritive tissues of galls induced by Ditylenchus gallaeformans (Nematoda) have promeristematic capacity, which may turn these galls into sinks of Al on their Melastomataceae Al-accumulating hosts. Such a sink of Al may affect gall growth and mineral nutrient intake. Based on the fact that galls are good models for plant developmental studies, we aimed to understand how Al-accumulating host plants in the Cerrado environment deal with Al toxicity in subcellular levels. Here, we used the ICP-OES method to check the variations on mineral nutrients, and the morin, hematoxylin, and Prussian blue stainings for Al and Fe histolocalization in galls induced on four Miconia species of the Brazilian Cerrado. We confirmed the new Al-accumulating feature for two Miconia species of the Cerrado environment. Furthermore, we found that Al accumulates in lesser concentrations in gall tissues than in non-galled tissues of the Miconia hosts. Staining methods indicated that the polyphenols avoid Al-binding to the apoplast and the nucleolus of the promeristematic cells, and mediated its binding to parenchyma cell walls. As well, we inferred that Fe3+ is transported by xylem and stored in gall parenchyma, where it is reduced to Fe2+, being available in gall nutritive cells. Our results demonstrated an Al compartmentalization between the apoplast and symplast of the inner cell layers in galls, as well as indicated the phenolics action against Al-toxicity and toward Fe availability for the diet of Ditylenchus gallaeformans.

Plant-galling insect interactions: a data set of host plants and their gall-inducing insects for the Cerrado.

Recent decades have seen increased research interest in the processes and mechanisms related to insect gall richness and host plants. The data set provided here includes 968 records of interactions between galling insects and host plants for the Cerrado biome. The data set comprises 505 species of 222 genera and 67 families of host plants. The botanical families most represented in the data set are Asteraceae, Fabaceae, Myrtaceae, Malpighiaceae, and Melastomataceae, which account for ~48.5% of all records and 52% of the total number of species. The gall-inducing insects listed in the data set include 48 species of Cecidomyiidae and one species of Tephritidae. This data set is the first to compile inventories of plant-galling insect communities and information about the diversity and distribution of insect galls and their host plants in the Cerrado. The data set reveals knowledge gaps and opportunities for future research on patterns of diversity and distribution, and provides a basis for generating and testing new ecological hypotheses. Please cite this data paper when using the current data in publications and let us know how the data are used in the publications. There are no copyright restrictions.

Hemicelluloses and associated compounds determine gall functional traits.

The intriguing questions concerning gall development refer to the processes of the remodelling of the host plant organ. Such processes involve the restructuring of cell walls and can be influenced by phenolics, indole-3-acetic acid (IAA) and reactive oxygen species (ROS). Alterations in cell walls demand the interference in the coupling of cellulose fibrils and hemicelluloses (xyloglucans) at specific stages of gall development. In addition to cell wall remodelling, hemicelluloses, such as the, xyloglucans and heteromannans can act as reserve carbohydrates, while xylans provide rigidity to the secondary cell walls. Developmental traits of the lenticular, fusiform and globoid galls on Inga ingoides (Fabaceae) were analysed using anatomical, cytometric, histochemical and immunocytochemical tools. Phenolics, IAA and ROS accumulated in similar gall tissue compartments, and may have influenced the restructuring of hemicelluloses and pectins. Contrary to expectations, cell wall flexibility regarding the dynamics of xyloglucans and cellulose fibrils does not relate to a temporal scale. The detection of xyloglucans in nutritive cell walls relate to carbohydrate nutritional resources to the galling insect, while xylans were associated to the lignified cell walls. Heteromanans were not detected, either in non-galled or galled tissues. The patterns of cell expansion during gall development relied on the relationship among phenolics, ROS and IAA with the hemicelluloses (xyloglucans and xylans) and cellulose fibrils. Although cell wall dynamics is specific to each gall morphotype in I. ingoides, the xyloglucans function as carbohydrate reserve to the gall inducers, which constitutes a functional trait common to the three morphotypes.

The mechanism of plant gall induction by insects: revealing clues, facts, and consequences in a cross-kingdom complex interaction

Galls are defined as modifications of the normal developmental design of plants, produced by a specific reaction to the presence and activity of a foreign organism. Although different organisms have the ability to induce galls in plants, insect-induced galls are the most elaborate and diverse. Some hypotheses have been proposed to explain the induction mechanism of plant galls by insects. The most general hypothesis suggests that gall formation is triggered by the action of chemical substances secreted by the gall inducer, including plant growth regulators such as auxins, cytokinins, indole-3-acetic acid (IAA), and other types of compounds. However, the mode of action of these chemical substances and the general mechanism by which the insect could control and manipulate plant development and physiology is still not known. Moreover, resulting from the complexity of the induction process and development of insect galls, the chemical hypothesis is very unlikely a complete explanation of the mechanism of induction and morphogenesis of these structures. Previous and new highlights of insect gall systems with emphasis on the induction process were analyzed on the basis of the author's integrated point of view to propose a different perspective of gall induction, which is provided in this article. Due to the extraordinary diversity of shapes, colors, and complex structures present in insect galls, they are useful models for studying how form and structure are determined at the molecular level in plant systems. Furthermore, plant galls constitute an important source of material for the study and exploration of new chemical substances of interest to humans, due to their physiological and adaptive characteristics. Considering the finely tuned control of morphogenesis, structural complexity, and biochemical regulation of plant galls induced by insects, it is proposed that an induction mechanism mediated by the insertion of exogenous genetic elements into the genome of plant gall cells could be involved in the formation of this kind of structure through an endosymbiotic bacterium.

Las agallas se definen como modificaciones del diseño y desarrollo normal de las plantas debido a una reacción específica a la presencia y actividad de un organismo foráneo. Aunque diferentes grupos de organismos tienen la habilidad de inducir agallas en plantas, las agallas inducidas por insectos son las más elaboradas y diversas. Algunas hipótesis han sido propuestas para explicar el mecanismo de inducción de las agallas de insectos. La hipótesis más general sugiere que la formación de las agallas es disparada por la acción de sustancias químicas secretadas por el insecto inductor, incluyendo reguladores de plantas como auxinas, citoquininas, ácido-3-indolacético (AIA) o bien otros tipos de compuestos. No obstante, el modo de acción de estas sustancias químicas y el mecanismo general por medio del cual el insecto podría controlar y manipular el desarrollo y fisiología de la planta es aún desconocido. Más aún, como resultado de la complejidad del proceso de inducción y desarrollo de las agallas de plantas inducidas por insectos, la hipótesis química es una explicación insuficiente e incompleta en relación con el mecanismo de inducción y morfogénesis de estas estructuras. Previas y nuevas evidencias relacionadas con el sistema de agallas de insectos, con énfasis en el proceso de inducción, fueron analizadas desde un punto de vista integral del autor para proponer en este artículo una perspectiva diferente sobre la inducción de este tipo de estructuras. Debido a la extraordinaria diversidad de formas, colores y estructuras complejas presentes en las agallas de insectos, las mismas constituyen modelos útiles para estudiar cómo la forma y la estructura son determinadas a nivel molecular en los sistemas vegetales. Además, las agallas de plantas son un importante origen de material para el estudio y exploración de nuevas sustancias químicas de interés humano, debido a las características fisiológicas y adaptativas que presentan. Considerando el control fino del proceso de morfogénesis, regulación bioquímica y complejidad estructural de las agallas de insectos, se propone que un mecanismo de inducción mediado por la inserción de elementos genéticos exógenos dentro del genoma de las células de la planta que forman la agalla podría estar involucrado en la formación de este tipo de estructuras, vía una bacteria endosimbiótica.

A new cecidogenous species of many-plumed moth (Alucitidae) associated with Cordiera A. Rich. ex DC. (Rubiaceae) in the Brazilian Cerrado

Larvae of many-plumed moths (Alucitidae), especially in the world-wide genus Alucita Linnaeus, 1758 are known as borers or gall-inducers on flowers, fruits and shoots of a few dicotyledonous families, including Bignoniaceae, Caprifoliaceae and Rubiaceae. However, there is no study available on the biology of the monotypic, Neotropical genus Prymnotomis Meyrick, 1931 except for its original description that was based on a single male, the holotype of Prymnotomis crypsicroca Meyrick, 1931 from Espirito Santo, Brazil. We describe here a second species for this genus, Prymnotomis cecidicola sp. nov. whose larvae induce galls on Cordiera elliptica (Cham.) Kuntze (Rubiaceae), a dioecious plant with dimorphic inflorescences found in the Brazilian Cerrado, Planaltina City, Federal District. Adults, larvae, pupae and galls are illustrated under light and scanning electron microscopy. Galls are green, spherical, unilocular and develop individually on C. elliptica flower buds. During development they look like fruits in shape and colour but are larger, do not have style scars when on female plants, and are induced also in male inflorescences. Pupation occurs outside the gall within a silk cocoon, presumably in the litter. A preliminary analysis of DNA barcode sequences including putative members of other alucitid lineages and Neotropical BINs (Barcode Index Number) supports Prymnotomis cecidicola sp. nov. as an independent phylogenetic unit, with 12 to 18% divergence. Its nearest-neighbour was the BIN cluster 5 (BOLD:AAA0842) that includes specimens from Costa Rica.(AU)

New distribution record, host plant and notes on natural history of Tomoplagia rudolphi (Lutz & Lima, 1918) (Diptera: Tephritidae)

In the state of Rio Grande do Sul, there are few records of geographical distribution and host plants to species of Tomoplagia Coquillett, as well as other genera of Tephritidae, especially those associated with plants of the family Asteraceae. Here, we report the first occurrence of Tomoplagia rudolphi (Lutz & Lima, 1918) in the state of Rio Grande do Sul, inducing stem galls in Vernonanthura tweediana (Baker) H. Rob. (Asteraceae, Vernonieae), whose plant becomes a new host record for this species. In this way, is increased to nine species of Tomoplagia recorded for Rio Grande do Sul. Biological and morphological data and photos of gall, larvae, pupae at new host and distribution map of the species in Brazil are provided.(AU)