Sugarcane response to two biotic stressors: Diatraea saccharalis and Mahanarva fimbriolata

In a field experiment in 2007/08 in São Paulo state, Brazil cane was exposed to sugarcane borer (Diatraea saccharalis) and spittlebug (Mahanarva fimbriolata) alone or in combination. Plots comprised 2 m(2) caged and uncaged sugarcane stalks. Compared with the caged (un-infested) control, spittlebug nymphs decreased cane yield by 17.6%, whereas infestation from spittlebug nymphs + sugarcane borer combined and sugarcane borer alone, decreased cane yields by 15.5% and 6.9%, respectively. There was no significant difference among the treatments in levels of soluble solids and cane sucrose content.

Influence of Mahanarva fimbriolata (Stål) (Hemiptera: Cercopidae) injury on the quality of cane juice

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Ultrastructural study of the salivary glands of the sugarcane spittlebug Mahanarva fimbriolata (Stal, 1854) (Euhemiptera : Cercopidae)

Spittlebugs are insects that suck sap from plants and regurgitate saliva containing toxic enzymes into the leaves. As a consequence, the conductive channels are blocked resulting in dry leaves, thus giving a burned aspect to the plantation. This work performed ultrastructural analyses of the salivary glands of the sugarcane spittlebug Mahanarva fimbriolata, since these organs produce the enzymes that are injected into the plants, thus being responsible for the economic losses in the production of sugarcane. Three kinds of secretory cells are found in principal gland, forming the lobules I-IV. The main differences among these cells relate to size, morphology and electron density of the secretory vesicles. The accessory glands contain different secretory vesicles to those in the principal gland. Muscular cells are found around the entire gland. The different secretory vesicles found in both principal and accessory glands indicate that the gland produces different substances or that the secretion in the interior of cells passes through a maturation process. (c) 2005 Elsevier Ltd. All rights reserved.

Ultrastructural study of the ovary of the sugarcane spittlebug Mahanarva fimbriolata (Hemiptera)

The present study describes the ultrastructure of meroistic telotrophic ovaries of the sugarcane spittlebug Mahanarva fimbriolata. In this type of ovary, nurse cells, oogonia, and prefollicular tissue are located at the terminal (distal) regions or tropharium of ovarioles. Oocytes in different developmental stages, classified from I to V, are observed in the vitellarium. Stage I oocytes do not exhibit intercellular spaces in the follicular epithelium, suggesting that synthesis and production of yolk during this stage occurs only through endogenous processes. Small yolk granules of different electron densities are present in the cytoplasm. Few lipid droplets are observed. Stage 11 oocytes exhibit small intercellular spaces in the follicular epithelium. More protein as well as lipid yolk granules are observed in the cytoplasm. In stage III oocytes, intercellular spaces in the follicular epithelium are larger than those observed in the previous stage. Electrondense protein granules of various sizes, larger than those observed in stage 11 oocytes predominate in the cytoplasm. Smaller lipid droplets are also present. In stage IV oocytes, the follicular epithelium exhibits large intercellular spaces. Our data clearly indicate that the opening of these spaces in the follicular epithelium of M. fimbriolata oocytes increases as the intake of exogenous proteins intensifies, that is, in stages IV and Voocytes. During these stages, granular yolk becomes viscous due to the lysis of granules. In stage Voocytes, viscous yolk predominates in the cytoplasm. This type of yolk, however, has not been described for other orders of insects. The chorion of M. fimbriolata oocytes consists of an external layer (exochorion) and an internal one (endochorion), which is in direct contact with the oocyte. Numerous small pores that probably facilitate oxygenation of the internal structures inside the eggs are observed in the exochorion. (c) 2006 Elsevier Ltd. All rights reserved.

Female reproductive system of the sugarcane spittlebug Mahanarva fimbriolata (Auchenorrhyncha): Vitellogenesis dynamics and protein quantification

The present study aimed describing the ovaries of the sugarcane spittlebug Mahanarva fimbriolata which are meroistic telotrophic with nurse cells and oocytes located in the tropharium. SEM revealed paired ovaries located dorsolaterally around the intestine, and oocytes exhibiting shapes ranging from round (less developed) to elliptic (more developed), suggesting a simultaneous, although, asynchronous development. Based on histological data we classified the oocytes in stages from I to V. Stage I oocytes exhibit follicular epithelium with cubic and/or prismatic cells, fine cytoplasmic granules. Stage II oocytes present intercellular spaces in the follicular epithelium due to the incorporation of yolk elements from the hemolymph. Small granules are present in the periphery of oocytes while larger granules are observed in the center. Stage III oocytes are larger and intercellular spaces in the follicular epithelium are evident, as well as the interface between follicular epithelium and oocyte. Yolk granules of different sizes are present in the cytoplasm. During this stage, chorion deposition initiates. Stage IV oocytes exhibit squamous follicular cells and larger intercellular spaces when compared to those observed in the previous stage. The oocyte cytoplasm present granular and viscous yolk, the latter is the result of the breakdown of granules. Stage V oocytes exhibit a follicular epithelium almost completely degenerated, smaller quantities of granular yolk and large amounts of viscous yolk. Based on our findings we established the sequence of yolk deposition in M. fimbriolata oocyte as follows: proteins and lipids, which are first produced by endogenous processes in stages I and II oocytes. Exogenous incorporation begins in stage III. In stages I and II oocytes, lipids are also produced by follicular epithelial cells. The third element to be deposited is polysaccharides, mainly found as complexes. Therefore, the yolk present in the oocytes of this species consists of glycolipoproteins. Molecular weights of proteins present in M. fimbriolata oocytes ranged from 10 to 92 KDa, differently from vitellogenin, the most common protein present in insect oocytes, weighing approximately 180 KDa. (c) 2006 Elsevier Ltd. All rights reserved.

Meiotic chromosomes and nucleolar behavior in testicular cells of the grassland spittlebugs Deois flavopicta, Mahanarva fimbriolata and Notozulia entreriana (Hemiptera, Auchenorrhyncha)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influência dos estressores bióticos Diatraea saccharalis (Fabr.) (Lepidoptera: Crambidae) e Mahanarva fimbriolata (Stål) (Hemiptera: Cercopidae) na produtividade e qualidade tecnológica da cana-de-açúcar

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Identificação em cana-de-açúcar de genes de resistência a Mahanarva fimbriolata (Stål, 1854) (Hemiptera: Cercopidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Danos causados por Mahanarva fimbriolata (STAL, 1854) na qualidade da cana e processo fermentativo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Infestação de Mahanarva fimbriolata (Stal, 1854) e controle químico na qualidade da matéria-prima e classificação do caldo de cana

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Incidência de Diatraea saccharalis Fabr., 1794 (Lepidoptera: Crambidae) e Mahanarva fimbriolata Stal, 1854 (Hemiptera: Cercopidae), produtividade e qualidade tecnológica da cana-de-açúcar em função da irrigação e da fertilização nitrogenada

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Diatraea saccharalis (Fabr.) (Lepidoptera: Crambidae) e Mahanarva fimbriolata (Stal) (Hemiptera: Cercopidae) em cana-de-açúcar: impacto na qualidade da matéria-prima, açúcar e etanol

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Qualidade da matéria-prima, microbiota fermentativa e produção de etanol sob ataque de Mahanarva fimbriolata em cana-de-açúcar

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Seleção e avaliação de campo de isolados de Metarhizium anisopliae (Metsch.) Sorok. para o controle da cigarrinha-da-raiz da cana-de-açúcar, Mahanarva fimbriolata (Stal,1854) (Hemiptera: Cercopidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Resistência de variedades de cana-de-açúcar à Cigarrinha-das-raízes Mahanarva fimbriolata (Stål) (Hemiptera, Cercopidae)

Pós-graduação em Agronomia - FEIS