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Impact of cultivation systems on Dichelops melacanthus (Dallas) (Heteroptera: Pentatomidae) population and damage and its chemical control on wheat
Chocorosqui, Viviane R.;Panizzi, Ant?nio R.;
Neotropical Entomology , 2004, DOI: 10.1590/S1519-566X2004000400014
Abstract: results of field evaluations indicated that the neotropical pentatomid dichelops melacanthus (dallas) is associated with wheat, triticum aestivum l. in the no-tillage cultivation system, adults and nymphs were mostly found on the soil, near the plant stems and underneath crop residues of the preceding summer crop, usually soybean, glycine max (l.) merrill, or corn, zea mays l. wheat grown under the conventional cultivation system showed minimal bug attack. d. melacanthus caused substantial damage to no-tillage wheat plants, particularly to seedlings. bug attack reduces the number of seed heads of up to 34%. seed yield was reduced in 31% due to the bugs' feeding, compared to plants free of damage. all developmental phases of the wheat plant were susceptible to the attack of d. melacanthus, and the greatest yield reduction occurred from stem elongation (26.5%) to milky grain stage (33.1%). seed treatment using insecticides was efficient, greatly reducing the grain production losses.
Danos do percevejo barriga-verde Dichelops melacanthus (Dallas) (Heteroptera: Pentatomidae) em trigo
Manfredi-Coimbra, Silvana;Silva, Jovenil José da;Chocorosqui, Viviane Ribeiro;Panizzi, Ant?nio Ricardo;
Ciência Rural , 2005, DOI: 10.1590/S0103-84782005000600003
Abstract: the objective of this study was to evaluate the reaction of two cultivars of wheat to the damage caused by adults of the green belly stink bug, dichelops melacanthus (dallas), confined on the culture from the beginning of tillering. the effect of different infestation levels (0, 2, 4, 8 and 16 bugs m-2) on the number of tillers m-2, number of spikes m-2, weight of 1,000 seeds (g), and yield (kg ha-1) was evaluated on wheat cvs. ?br 18' and ?brs 193', in londrina, paraná state. the number of tillers m-2 increased linearly on ?br 18' and in a quadratic form on ?brs 193', with the increase of the number of bugs m-2; the number of spikes m-2, the weight of 1,000 seeds, and the yield decreased linearly with the increase of the infestation level on both cultivars. ?brs 193' was the most susceptible to the attack of d. melacanthus, showing a reduction of 254.4kg for each unit of increase in the number of bugs m-2.
Photoperiod influence on the biology and phenological characteristics of Dichelops melacanthus (Dallas, 1851) (Heteroptera: Pentatomidae)
Chocorosqui, V. R.;Panizzi, A. R.;
Brazilian Journal of Biology , 2003, DOI: 10.1590/S1519-69842003000400012
Abstract: the influence of the photoperiod on the biology and seasonal morphs of dichelops melacanthus (dallas, 1851) was studied in the laboratory. four different photoperiods (11, 12, 13, and 14 hl = hours of light) were tested, keeping the temperature at 25 ± 1oc and the relative humidity at 65 ± 5%. nymph developmental time tended to be longer under shorter photophases (11 and 12 hl). the 14-hour photophase (long day) resulted in lower nymph mortality rates. females maintained at 13 and 14 hl showed greater weight gain (1st-28th day) than females under 12 hl. d. melacanthus showed reproductive oligopause induced by short photophases, especially when exposed to 11 hl. under 13 and 14 hl, 85% and 65% of females oviposited, respectively, in comparison to 10% and 15% of females ovipositing under 11 and 12 hl, respectively. fecundity (number of egg masses and number of eggs/female) was greater in the longer than under the shorter photophases. seasonal dimorphism induced by photoperiod was observed in d. melacanthus adults. under short-day conditions (11 and 12 hl), adults showed short and rounded shoulder spines, grayish brown abdomen (mainly in 11 hl), high lipid contents, and lower percentage of mature reproductive organs. under long-day conditions (13 and 14 hl), the stink bugs showed greatly developed shoulder spines, green abdomen, low lipid contents, and mature reproductive organs.
Photoperiod influence on the biology and phenological characteristics of Dichelops melacanthus (Dallas, 1851) (Heteroptera: Pentatomidae)  [cached]
Chocorosqui V. R.,Panizzi A. R.
Brazilian Journal of Biology , 2003,
Abstract: The influence of the photoperiod on the biology and seasonal morphs of Dichelops melacanthus (Dallas, 1851) was studied in the laboratory. Four different photoperiods (11, 12, 13, and 14 hL = hours of light) were tested, keeping the temperature at 25 ± 1oC and the relative humidity at 65 ± 5%. Nymph developmental time tended to be longer under shorter photophases (11 and 12 hL). The 14-hour photophase (long day) resulted in lower nymph mortality rates. Females maintained at 13 and 14 hL showed greater weight gain (1st-28th day) than females under 12 hL. D. melacanthus showed reproductive oligopause induced by short photophases, especially when exposed to 11 hL. Under 13 and 14 hL, 85% and 65% of females oviposited, respectively, in comparison to 10% and 15% of females ovipositing under 11 and 12 hL, respectively. Fecundity (number of egg masses and number of eggs/female) was greater in the longer than under the shorter photophases. Seasonal dimorphism induced by photoperiod was observed in D. melacanthus adults. Under short-day conditions (11 and 12 hL), adults showed short and rounded shoulder spines, grayish brown abdomen (mainly in 11 hL), high lipid contents, and lower percentage of mature reproductive organs. Under long-day conditions (13 and 14 hL), the stink bugs showed greatly developed shoulder spines, green abdomen, low lipid contents, and mature reproductive organs.
Danos do percevejo barriga-verde Dichelops melacanthus (Dallas) (Heteroptera: Pentatomidae) em trigo  [cached]
Manfredi-Coimbra Silvana,Silva Jovenil José da,Chocorosqui Viviane Ribeiro,Panizzi Ant?nio Ricardo
Ciência Rural , 2005,
Abstract: O objetivo deste estudo foi avaliar a rea o de dois cultivares de trigo aos danos causados por percevejos adultos de Dichelops melacanthus (Dallas), confinados sobre a cultura a partir do início do perfilhamento. Foram comparados os efeitos de diferentes níveis de infesta o (0, 2, 4, 8 e 16 percevejos m-2) sobre o número de perfilhos m-2, número de espigas m-2, peso de mil sementes (g) e rendimento (kg ha-1) das cultivares ?BR 18' e ?BRS 193' de trigo, em Londrina, PR. O número de perfilhos m-2 cresceu linearmente para a cv. ?BR 18' e de forma quadrática para a cv. ?BRS 193' com o aumento do número de percevejos m-2; o número de espigas m-2, o peso de mil sementes, e o rendimento decresceram de forma linear com o aumento do nível de infesta o para as duas cultivares. ?Acv.BRS 193' foi mais suscetível ao ataque de D. melacanthus, apresentando uma redu o de 254,4kg para cada unidade de aumento no número de percevejos m-2.
Nymph and adult biology of Dichelops melacanthus (Dallas) (Heteroptera: Pentatomidae) feeding on cultivated and non-cultivated host plants
Chocorosqui, Viviane R.;Panizzi, Ant?nio R.;
Neotropical Entomology , 2008, DOI: 10.1590/S1519-566X2008000400001
Abstract: the biology of the pentatomid dichelops melacanthus (dallas) feeding on cultivated and non-cultivated plants was studied in the laboratory. nymph mortality varied from ≈ 60 on corn (seed mature) to 77% on wheat (ear immature); no nymphs survived on seedlings of corn or wheat. nymph developmental time on soybean, corn or wheat (seed, pod or ear) varied from 25.5 to 32.8 days. body weight at adult emergence was similar and greater on most foods than on wheat ear. nymphs fed preferentially on soybean (pod immature). on non-cultivated hosts, nymphs showed high mortality (73%) on crotalaria (pod immature); on tropical spiderwort (stem) all nymphs died. nymphs took longer time to develop on crotalaria and/or on spiderwort than on soybean. body weight at adult emergence did not differ on crotalaria or soybean. survivorship decreased with time on most foods, with ≈50% of adults alive at day 30. on corn and wheat seedlings ≈80% of adults were dead on day 20. adult longevity ranged 31-43 days, except on corn and wheat seedlings < 15 days. females % ovipositing peaked (≈76%) on soybean (pod or seed immature), and was minimum (≈9%) on wheat ear (immature); no females reproduced on seedlings of corn or wheat. preoviposition period was shorter (≈12 days) on soybean (immature pod or seed) and longer (≈37 days) on wheat (ear immature). fecundity was similar and higher on all foods than on wheat (ear immature). body weigh gain occurred on all foods, but on corn and wheat seedlings. adults fed preferably on soybean (pod immature and seed mature); wheat (seedling) was the least preferred food.
Identification of defensive compounds in metathoracic glands of adults of the stink bug Dichelops melacanthus (Hemiptera: Pentatomidae)
Marques, Francisco A.;Wendler, Edison P.;Maia, Beatriz Helena L. N. Sales;Ventura, Maurício U.;Arruda-Gatti, Iara Cintra;
Journal of the Brazilian Chemical Society , 2007, DOI: 10.1590/S0103-50532007000600020
Abstract: the contents of metathoracic glands of adults of the stink bug dichelops melacanthus (hemiptera: pentatomidae) were analyzed. compounds were identified by gas chromatography (gc), coupled gc-mass spectrometry and matching retention indices and mass spectra with those of authentic samples. tridecane was the major component followed by lesser and approximately equal amounts of (e)-4-oxo-2-hexenal and (e)-2-octenal. other compounds identified include (e)-2-hexenal, decane, (e)-2-hexenyl acetate, undecane, (e)-4-oxo-2-octenal, dodecane, (e)-2-octenyl acetate, 1-tridecene, tetradecane and pentadecane.
Nymph developmental time and survivorship, adult longevity, reproduction and body weight of Dichelops melacanthus (Dallas) feeding on natural and artificial diets
Panizzi, Ant?nio R.;Duo, Leandro J. S.;Bortolato, Nágila M.;Siqueira, Fábio;
Revista Brasileira de Entomologia , 2007, DOI: 10.1590/S0085-56262007000400013
Abstract: the biology of nymphs and adults of the neotropical pentatomid, dichelops melacanthus (dallas), feeding on the natural foods, soybean, glycine max (l.) merrill immature pods, and corn, zea mays l. immature seeds, and on an artificial dry diet, was studied in the laboratory. nymph developmental time was shorter on the natural foods (ca. 21-22 days) than on the artificial diet (28 days), and most nymphs reached adulthood on the food plants (55% on soybean and 73% on corn) than on the artificial diet (40%). fresh body weight at adult emergence was similar and higher for females raised as nymphs on the natural foods, compared to females from nymphs raised on the artificial diet; for males, weights were similar on all foods. mean (female and male) survivorship up to day 20, decreased from 55% on soybean to 40% on corn, down to 0% on the artificial diet. total longevity for females was higher on soybean, while for males was similar on all foods. about three times more females oviposited on soybean than on corn, but fecundity/female was similar on both foods. on the artificial diet, only one out of 30 females oviposited. fresh body weight of adults increased significantly during the first week of adult life, and at the end of the 3rd week, weight gain was similar on all foods.
Rostrum length, mandible serration, and food and salivary canals areas of selected species of stink bugs (Heteroptera, Pentatomidae)
Depieri, Rogério A.;Panizzi, Ant?nio R.;
Revista Brasileira de Entomologia , 2010, DOI: 10.1590/S0085-56262010000400008
Abstract: laboratory studies were conducted to compare rostrum length morphology of mandible serration and area of food and salivary canals of dichelops melacanthus (dallas) (dm), euschistus heros (f.) (eh), nezara viridula (l.) (nv), and piezodorus guildinii (westwood) (pg) (heteroptera: pentatomidae). nv showed the longest (5.9 mm) and pg the shortest (3.5 mm) rostrum length; dm and eh were intermediate. length and width of mandible tip areas holding serration was bigger for nv (106.0 and 30.2 μm, respectively) and smaller for pg (71.1 and 23.7 μm), with all species having four central teeth and three pairs of lateral teeth. the inner mandible surface showed squamous texture. cross-section of food and salivary canals (fc and sc) indicated greater area for nv and dm compared to eh and pg; however, the ratio fc/sc, yielded the highest relative area for pg.
Egg parasitoid wasps as natural enemies of the neotropical stink bug Dichelops melacanthus
Laumann, Raúl Alberto;Moraes, Maria Carolina Blassioli;Silva, Joseane Padilha da;Vieira, Afranio Márcio Corrêa;Silveira, Samantha da;Borges, Miguel;
Pesquisa Agropecuária Brasileira , 2010, DOI: 10.1590/S0100-204X2010000500002
Abstract: the objective of this work was to determine the potential of five species of scelionidae wasps - telenomus podisi, trissolcus basalis, trissolcus urichi, trissolcus teretis and trissolcus brochymenae - as natural enemies of the neotropical stink bug dichelops melacanthus, and to determine if the presence of eggs of other stink bug species influences the parasitism and development of the parasitoids. two kinds of experiments were done in laboratory: without choice of hosts (eggs of d. melacanthus) and with choice (eggs of d. melacanthus and of euschistus heros). biological parameters, including proportion of parasitism, immature survivorship, progeny sex ratio, immature stage development period, and host preference were recorded. all the evaluated parasitoids can parasitize and develop on d. melacanthus eggs. the first choice of eggs did not influence the proportion of d. melacanthus eggs parasitized by tr. basalis, tr. teretis or tr. brochymenae. however, d. melacanthus eggs as the first choice of te. podisi and tr. urichi increased, respectively, 9 and 14 times the chance for parasitism on eggs of this species. behavioral and ecological aspects of parasitoids should be considered prior to their use in biological control programs.
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