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Effect of sugarcane varieties on the development of Mahanarva fimbriolata (Hemiptera: Cercopidae)
GARCíA,JOSé F.; PRADO,SIMONE S; VENDRAMIM,JOSé D.; M. BOTELHO,PAULO S.;
Revista Colombiana de Entomología , 2011,
Abstract: the sugarcane spittlebug, mahanarva fimbriolata (hemiptera: cercopidae), is considered the most important pest of sugarcane harvested without the burning of trash, or green cane, in brazil. the objective of this work was to compare the biology of m. fimbriolata on six sugarcane varieties: sp79-1011, sp80-1816, sp80-1842, sp81-3250, rb72454, and rb835486. the experiments were conducted at a temperature of 25 ± 1°c, rh of 70 ± 10%, and a photoperiod of 14:10 [l:d]. variety rb72454 outperformed the rest, reducing the nymphal population that fed on its roots by 50%. with regard to adults, variety sp81-3250 allowed greater mean longevity of males (38 days) and females (51 days), greater mean oviposition period (46 days), and higher mean fecundity (1215 eggs/female); these parameters were statistically different from those obtained with other varieties. for the eggs, there was no significant effect of variety on developmental time or viability. consequently, the variety sp81-3250 should be avoided in areas predisposed to the occurrence of m. fimbriolata.
Feeding site of the spittlebug Mahanarva fimbriolata (St?l) (Hemiptera: Cercopidae) on sugarcane
Garcia, José Francisco;Grisoto, Eliane;Botelho, Paulo Sérgio Machado;Parra, José Roberto Postali;Appezzato-da-Glória, Beatriz;
Scientia Agricola , 2007, DOI: 10.1590/S0103-90162007000500014
Abstract: the sugarcane spittlebug mahanarva fimbriolata (st?l) (hemiptera: cercopidae) is a pest of mechanically-harvested sugarcane in brazil, when trash burning is not performed. to better understand the differences in feeding behavior of adults and nymphs of this pest and the subsequent disorders that arise, stylet penetration through fixation, staining and sectioning was investigated. nymphs cause a "physiological disorder" damaging the tracheary system of the roots, slowing or preventing water and nutrient flow, with phloem and xylem dehydration. nymphs insert their stylets through the epidermis, crossing the cortex, endodermis and pericycle before reaching the vascular cylinder, where they feed in the sieve-tube elements of the primary phloem. in contrast, adults feed on leaves, causing "sugarcane burn", and reducing plant photosynthesis. adults introduce the stylets into the leaf blade through the stomata, passing the chlorophyll-bearing parenchyma cells before reaching the metaxylem in the vascular bundles.
Effect of sugarcane varieties on the development of Mahanarva fimbriolata (Hemiptera: Cercopidae) Efecto de variedades de ca a de azúcar en el desarrollo de Mahanarva fimbriolata (Hemiptera: Cercopidae)
JOSé F. GARCíA,SIMONE S PRADO,JOSé D. VENDRAMIM,PAULO S. M. BOTELHO
Revista Colombiana de Entomología , 2011,
Abstract: The sugarcane spittlebug, Mahanarva fimbriolata (Hemiptera: Cercopidae), is considered the most important pest of sugarcane harvested without the burning of trash, or green cane, in Brazil. The objective of this work was to compare the biology of M. fimbriolata on six sugarcane varieties: SP79-1011, SP80-1816, SP80-1842, SP81-3250, RB72454, and RB835486. The experiments were conducted at a temperature of 25 ± 1°C, RH of 70 ± 10%, and a photoperiod of 14:10 [L:D]. Variety RB72454 outperformed the rest, reducing the nymphal population that fed on its roots by 50%. With regard to adults, variety SP81-3250 allowed greater mean longevity of males (38 days) and females (51 days), greater mean oviposition period (46 days), and higher mean fecundity (1215 eggs/female); these parameters were statistically different from those obtained with other varieties. For the eggs, there was no significant effect of variety on developmental time or viability. Consequently, the variety SP81-3250 should be avoided in areas predisposed to the occurrence of M. fimbriolata. El salivazo, Mahanarva fimbriolata (Hemiptera: Cercopidae), es considerada la principal plaga de la ca a de azúcar cosechada sin previa limpieza a fuego, o ca a verde, en el Brasil. El objetivo de este trabajo fue comparar la biología de M. fimbriolata sobre seis variedades de ca a de azúcar: SP79-1011, SP80-1816, SP80-1842, SP81-3250, RB72454 y RB835486. Los experimentos se llevaron a cabo a una temperatura de 25 ± 1°C, UR de 70 ± 10% y un fotoperíodo de 14:10 [L:O]. La variedad RB72454 superó las demás, reduciendo en 50% la población de ninfas alimentadas en sus raíces. En relación con los adultos, la variedad SP81-3250 permitió mayor longevidad promedio de machos (38 días) y de hembras (51 días), mayor periodo promedio de oviposición (46 días) y elevada fecundidad promedio (1215 huevos/hembra); estos parámetros fueron estadísticamente diferentes de los obtenidos en las otras variedades. Para los huevos, no hubo efecto significativo de variedad sobre el periodo de desarrollo o la viabilidad. Siendo así, la variedad SP81-3250 debe ser evitada en áreas propicias para la presencia de M. fimbriolata.
Biology and fertility life table of Mahanarva fimbriolata (St?l) (Hemiptera: Cercopidae) in sugarcane
Garcia, José Francisco;Botelho, Paulo Sérgio Machado;Parra, José Roberto Postali;
Scientia Agricola , 2006, DOI: 10.1590/S0103-90162006000400001
Abstract: mahanarva fimbriolata (st?l) (hemiptera: cercopidae) is the most important pest of sugarcane harvested without the use of fire to burn leaf trash. its biology was studied for three generations in order to obtain basic information about its life cycle. a fertility life table was used to evaluate the quality of laboratory-reared insects. data were obtained at a temperature of 25 ± 1oc, rh of 70 ± 10%, and a 14-hour photophase. the incubation period lasted 21 days with a viability of 81%; the nymph stage had a duration of 37 days, with a 94% viability; the male and female longevities were 18 and 23 days, respectively, with a pre-oviposition period of 5 days and an oviposition period of 16 days, with a fecundity of 342 eggs, with a life-cycle (egg-adult) of 60 days. a net reproductive rate (ro) of 131 females produced per female per generation was measured, with a finite rate of increase (l) of 1.085. the fertility life table proved to be adequate to be evaluate the quality of laboratory-reared m. fimbriolata populations.
Screening of entomopathogenic nematodes to control Mahanarva fimbriolata (Hemiptera: Cercopidae)
DE PAULA BATISTA,ELDER SIM?ES; AUAD,ALEXANDER M.; DE RESENDE,TIAGO TEIXEIRA; DE OLIVEIRA MONTEIRO,CAIO MáRCIO;
Revista Colombiana de Entomología , 2011,
Abstract: we aimed to screen entomopathogenic nematodes (epns) strains against the root spittlebug, mahanarva fimbriolata. an assay was performed at laboratory in which nymphs of the insect were exposed to seven epns strains (steinernema anomali, s. carpocapsae, s. feltiae, s. riobravis, heterorhabditis amazonensis rsc5, h. bacteriophora hp88 and h. baujardi lpp7) under three concentrations (200, 400 and 800 epns/nymph). after the laboratory screening a greenhouse assay was carried out using the most pathogenic strains. increasing concentration didn't increase nymph mortality at laboratory. the root spittlebug nymphs were susceptible to all strains, with 48% (s. carpocapsae) and 72% (s. feltiae) pathogenicity extremes. a decrease in efficiency was observed in greenhouse tests compared with laboratory tests.
Screening of Metarhizium anisopliae (Metsch.) Sorok. strains against Mahanarva fimbriolata (Stal, 1854) (Hemiptera: Cercopidae)/ Sele o de isolados de Metarhizium anisopliae (Metsch.) Sorok. a Mahanarva fimbriolata (Stal, 1854) (Hemiptera: Cercopidae)  [cached]
Daniella Macedo,Sérgio Batist Alves,Solange Aparecida Vieira
Semina : Ciências Agrárias , 2006,
Abstract: The mechanized harvest of sugarcane results in accumulation of mulch on the soil and promotes favorable temperature and moist to development of sugarcane root spittlebug, Mahanarva fimbriolata (Stal, 1854) (Hemiptera: Cercopidae). High populations of this pest causes serious damages to plants and high costs with insecticides. This research work tested strains of Metarhizium anisopliae (Metsch.) Sorok. pathogenic to sugarcane root spittlebug using a new methodology. The selection was carried out in laboratory conditions. Nymphs were sprayed with 2 mL of a suspension containing 5x107 conidia/mL and maintained in roots of sugarcane. The corrected mortality was evaluated five days after pulverization and ranged from 10.5 to 60% and the more pathogenic strains caused mortality from 46.5 to 59.7%. A colheita mecanizada de cana-de-a úcar, sem a queima da palhada, proporciona acúmulo de matériaorganica no solo tornando o ambiente favorável ao desenvolvimento da cigarrinha-da-raiz, Mahanarva fimbriolata (Stal, 1854) (Hemiptera: Cercopidae). Em elevadas infesta es essa praga tem causado prejuízos devido aos grandes danos nas plantas e aos gastos com agrotóxicos. O objetivo da pesquisa foi selecionar isolados de Metarhizium anisopliae (Metsch.) Sorok. patogênicos para cigarrinha-da-raiz, usando uma nova metodologia. A sele o foi feita em condi es de laboratório, utilizando-se ninfas coletadas a campo que foram pulverizadas com o fungo e mantidas em raiz de mudas de cana-de-a úcar. A mortalidade corrigida ao quinto dia após a inocula o variou de 10,5 a 60%, sendo que os isolados mais patogênicos causaram mortalidades de 46,5 a 59,7%.
Selección de nematodos entomopatogenicos para el control de Mahanarva fimbriolata (Hemiptera: Cercopidae) Screening of entomopathogenic nematodes to control Mahanarva fimbriolata (Hemiptera: Cercopidae)
ELDER SIM?ES DE PAULA BATISTA,ALEXANDER M. AUAD,TIAGO TEIXEIRA DE RESENDE,CAIO MáRCIO DE OLIVEIRA MONTEIRO
Revista Colombiana de Entomología , 2011,
Abstract: Se seleccionaron aislamientos de nematodos entomopatogénicos (NEPs) contra el salivazo de los pastos, Mahanarva fimbriolata. Se desarrolló un experimento en laboratorio donde ninfas de salivazo se expusieron a siete aislamientos (Steinernema anomali, S. carpocapsae, S. feltiae, S. riobravis, Heterorhabditis amazonensis RSC5, H. bacteriophora HP88 y H. baujardi LPP7) en tres concentraciones (200, 400 y 800 NEP/ninfa). Luego de la selección de los aislamientos más virulentos en laboratorio, se efectuó un experimento en invernadero. El aumento de la concentración no proporcionó incremento en la mortalidad ninfal de M. fimbriolata en laboratorio. Las ninfas de salivazo fueron susceptibles a todos los aislamientos, destacándose S. riobravis con un 90% de mortalidad, y S. feltiae con un 80%. El desempe o en invernadero no fue diferente entre los aislados, alcanzando una mortalidad ninfal de 48% (S. carpocapsae) y 72% (S. feltiae). Hay disminución de la eficiencia de los nematodos en invernadero comparada con la eficiencia en laboratorio. We aimed to screen entomopathogenic nematodes (EPNs) strains against the root spittlebug, Mahanarva fimbriolata. An assay was performed at laboratory in which nymphs of the insect were exposed to seven EPNs strains (Steinernema anomali, S. carpocapsae, S. feltiae, S. riobravis, Heterorhabditis amazonensis RSC5, H. bacteriophora HP88 and H. baujardi LPP7) under three concentrations (200, 400 and 800 EPNs/nymph). After the laboratory screening a greenhouse assay was carried out using the most pathogenic strains. Increasing concentration didn't increase nymph mortality at laboratory. The root spittlebug nymphs were susceptible to all strains, with 48% (S. carpocapsae) and 72% (S. feltiae) pathogenicity extremes. A decrease in efficiency was observed in greenhouse tests compared with laboratory tests.
Induction of insect plant resistance to the spittlebug Mahanarva fimbriolata St?l (Hemiptera: Cercopidae) in sugarcane by silicon application
Kornd?rfer, AP;Grisoto, E;Vendramim, JD;
Neotropical Entomology , 2011, DOI: 10.1590/S1519-566X2011000300013
Abstract: changes in the agroecosystem with the increase of green cane harvesting in brazil affected the insect populations associated to this crop, and secondary pests like the spittlebug mahanarva fimbriolata st?l, became much more important. many studies have demonstrated the active role played by silicon in plant defense against herbivory. the objective of this study was to evaluate the effects of silicon applications on the biology of the spittlebug reared on two resistant (sp79-1011 and sp80-1816) and one susceptible (sp81-3250) sugarcane cultivars. sugarcane plants were grown under greenhouse conditions and submitted to different treatments: with and without silicon fertilizer in two different soil type (sandy and clay soil). the newly hatched nymphs were transferred to sugarcane roots and placed into boxes with lids, to keep a moistened and dark environment favoring their growth and maintenance of the root system, providing food access to the developing nymphs. after emergence, adult males and females were placed in cages for mating and oviposition. the silicon absorbed and accumulated in the plant caused an increase in nymphal mortality, and depending on the sugarcane cultivar tested this element also provided an increase in the duration of the nymphal stage and a decrease in the longevity of males and females. 'sp79-1011' presented the highest silicon content in leaves, and m. fimbriolata had the highest nymph mortality and the shortest female longevity. the pre-oviposition period, fecundity and egg viability were not affected by the silicon content in plants or the cultivar used.
Economic injury level for sugarcane caused by the spittlebug Mahanarva fimbriolata (St?l) (Hemiptera:Cercopidae)
Dinardo-Miranda, Leila Luci;Pivetta, Jo?o Paulo;Fracasso, Juliano Vilela;
Scientia Agricola , 2008, DOI: 10.1590/S0103-90162008000100003
Abstract: the sugarcane spittlebug, mahanarva fimbriolata (st?l), is currently one of the most important pests of the sugarcane crop in brazil. in spite of its economic importance, advances in the management of this pest have been limited by the lack of information on the economic injury level. in this study, the economic injury level for m. fimbriolata was estimated in a field experiment, over areas harvested in september, applying thiamethoxam at 200 g a.i. ha-1 or imidacloprid at 720 g a.i. ha-1. in one of the experiments, insecticide applications were made at pest infestation values of 4.2 (11/12/04), 7.1 (01/11/05), or 16.3 (01/18/05) insects m-1, and in experiment 2 when pest populations were 5.6 (11/12/04), 8.5 (01/11/05), or 15.3 (01/11/05) insects m-1. control plots without insecticide were maintained. after the applications, spittlebug infestations were estimated monthly, and the experiments were harvested in september 2005. spittlebug control with the application of insecticides resulted in stalk and sugar yield increases in relation to the control, for both experiments. applications performed under smaller infestations resulted in higher yields than applications made under higher populations. there were no differences between insecticides in one of the experiments; in the other, however, thiamethoxan contributed to greater yield increases than imidacloprid. insecticide applications made under lower infestations resulted in greater profits. regression analyses allowed the estimation of the pest economic injury level to be between 2 to 3 insects m-1 for the conditions of this experiment.
Influence of Mahanarva fimbriolata (St?l) (Hemiptera: Cercopidae) injury on the quality of cane juice
Madaleno, Leonardo L.;Ravaneli, Gisele C.;Presotti, Leandro E.;Mutton, Miguel A.;Fernandes, Odair A.;Mutton, Márcia J.R.;
Neotropical Entomology , 2008, DOI: 10.1590/S1519-566X2008000100010
Abstract: mahanarva fimbriolata (st?l) is an important pest in latin america and causes significant reduction in sugarcane productivity. there is no information regarding the effect of this pest on the quality of cane juice used for sugar and alcohol production. this work aimed at evaluating the quality of sugarcane juice from plants attacked by spittlebugs. the experiment was arranged in a completely randomized design with 15 replications, and comprised two treatments: control and chemical treatment with thiamethoxam. an average of 9.2 ± 4.44 spittlebug nymphs m-1 were found in the plots prior to insecticide application. nymphs were counted 18, 35, 55, and 82 days after the initial sampling (december/2003). during the mid growing season (july 2004), the juice was extracted from stalks and analyzed for brix, pol, rs, ph, fiber, purity, trs, dextran, starch, and total phenolic compounds. stalk yield was also measured. chemical treatment was efficient in reducing spittlebug population, and elevated both stalk yield and juice ph. the accumulated infestation expressed as insect-days was significantly and negatively correlated to yield, pol, ph, and purity. the concentration of phenolic compounds increased with pest infestation, while dextran and starch levels were not affected. the infestation of 2.4 and 7.3 nymphs m-1 day-1 caused reductions of 8.3% and 29.8% in yield; 1.9% and 5.8% in pol; 0.4% and 1.1% in ph and 0.4% and 1.2% in purity, respectively, in comparison to areas where the pest population was extremely low (< 0.1 nymphs m-1).
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