52a Reunião Anual da Sociedade Brasileira de
Zootecnia
Zootecnia: Otimizando Recursos e Potencialidades
Belo Horizonte – MG, 19 a 23 de Julho de 2015
Selecionando genótipos do gênero Paspalum para resistência à cigarrinha-das-pastagens Notozulia entreriana
(Berg, 1879) (Hemiptera: Cercopidae)1
José Raul Valério2, Fabrícia Zimermann Vilela Torres2, Marcos Rafael Gusmão3, Ewerton da Costa Lira4, Glenda
Moreira Weis5, Welligton Valadão Ferreira de Paula6, Marlene Conceição Monteiro Oliveira7
1
Activity component of the Embrapa Cattle-Southeast Forage Evaluation program
Scientific Researcher, Embrapa Beef Cattle, 830 Radio Maia Ave.; Campo Grande, MS 79106- 550, Brazil; [email protected];
[email protected]
3
Scientific Researcher, Embrapa Cattle-Southeast, São Carlos, SP, Brazil; [email protected]
4
Embrapa scholar, Agronomy student at Dom Bosco Catholic University (UCDB), Campo Grande, MS, Brazil; [email protected]
5
CNPq scholar, Agronomy student at Dom Bosco Catholic University (UCDB), Campo Grande, MS, Brazil; [email protected]
6
UNIPASTO scholar, Agronomy student at Dom Bosco Catholic University (UCDB), Campo Grande, MS, Brazil; [email protected]
7
AGRAER/MS. Rural Development Technician at Embrapa Gado de Corte; [email protected]
2
Resumo: Os danos causados pelas cigarrinhas representam problema relevante dentro da Bovinocultura de corte
nacional. As cigarrinhas reduzem a produção, a qualidade e a capacidade de suporte das pastagens. A importância
desses insetos se deve, em grande parte, às extensas monoculturas estabelecidas com um número reduzido de
espécies de gramíneas forrageiras. A diversificação de pastagens com o uso de gramíneas resistentes às cigarrinhas
apresenta grande potencial, havendo, portanto, a necessidade de se encontrar fontes de resistência a estes insetos.
Neste ensaio, 21 genótipos do gênero Paspalum foram comparados quanto à resistência à cigarrinha Notozulia
entreriana, através dos parâmetros, percentual de sobrevivência de ninfas e, duração do período ninfal. O ensaio foi
conduzido em casa de vegetação. Objetivou-se identificar os genótipos menos adequados para o desenvolvimento e
sobrevivência do inseto. As infestações foram feitas três meses após o plantio, utilizando-se cinco ovos por vaso.
Houve dez repetições para cada genótipo. Como critério de seleção, tem-se adotado a escolha dos genótipos nos
quais são constatados níveis de sobrevivência abaixo da média do ensaio, menos um desvio padrão e, períodos
ninfais acima da média do grupo, mais um desvio padrão. Com base nesse critério, selecionaram-se dois genótipos
de códigos BRA10537 e BRA19186. Outros dez genótipos, com baixa sobrevivência, estiveram próximos de
atender ao critério de seleção e deverão ser reavaliados.
Palavras–chave: gramínea forrageira, ninfas, resistência de plantas a insetos
Selecting genotypes of the genus Paspalum for resistance to the pasture spittlebug Notozulia entreriana
(Berg, 1879) (Hemiptera: Cercopidae)
Abstract: Spittlebugs are important biotic restrictions in the Brazilian Beef Cattle Industry. Such insects reduce
forage production and quality, resulting in lower stocking rates. The importance of these insects is due, in large
part, to the extensive monocultures established with a reduced number of forage grasses species. Pasture
diversification including spittlebug resistant grasses has great potential. It is, therefore, of great importance to find
sources of resistance to this group of insects. In the present work, 21 genotypes of the genus Paspalum were
evaluated for resistance to the spittlebug Notozulia entreriana, based on the parameters, nymphal survival and
duration of the nymphal period. The assay was conducted in the greenhouse. The plants were infested, three months
after planting, with five spittlebug eggs per pot, in ten replications. The emerging adults were collected daily. As
screening criterion, only the genotypes presenting, simultaneously, percent of nymphal survival below the average
for the group, minus the correspondent standard deviation and, nymphal period above the average for the group plus
the respective standard deviation, are selected as resistant. Two Paspalum genotypes (codes BRA10537 and
BRA19186) were selected as more resistant in this trial. Ten other Paspalum genotypes, presenting low
survivorship, were close to fulfill with the established criterion and, for this reason, will be reevaluated.
Keywords: forage grass, froghopper, host plant resistance, insecta
Introduction
Spittlebugs are autochthonous sucking insects that have adapted to various introduced grasses in Brazil,
particularly those belonging to the genera Brachiaria, Panicum, Pennisetum and Cynodon. Such insects reduce
forage production and quality, resulting in lower stocking rates (Valério et al., 2001). Chemical control, widely used
in high-value crops, is too costly and seldom used for pastures in Brazil. Considering that the importance of these
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52a Reunião Anual da Sociedade Brasileira de
Zootecnia
Zootecnia: Otimizando Recursos e Potencialidades
Belo Horizonte – MG, 19 a 23 de Julho de 2015
insects in Brazil, in large part, is due to the extensive monocultures established with a reduced number of forage
grasses species, pasture diversification, including spittlebug resistant grasses, has great potential. The objective of
the present work was to evaluate genotypes of the genus Paspalum, from the germplasm available at Embrapa
Cattle-Southeast, for resistance to the forage spittlebug Notozulia entreriana.
Material e Methods
The assay was conducted in the greenhouse using, with minor modifications, methodology described by
Lapointe et al. (1992). Twenty one genotypes were initially established in a hydroponic system, then planted in
small plastic cups and, posteriorly transferred to 17 cm diameter plastic pots. Each of these pots was covered with
aluminum tops, which have a central opening for the grass stems. This is done in order to stimulate abundant
superficial rooting at the soil surface and hence provide enough feeding sites for the newly hatched nymphs. The
plants were infested three months after planting with five eggs per pot. There were ten replications for each
genotype in a complete randomized assay. Close to adult emergence, the pots were individually caged. The
emerging adults were collected daily. As screening criterion, only the genotypes presenting, simultaneously,
percentage of nymphal survival below the average for the group, minus the correspondent standard deviation and,
nymphal period above the average for the group, plus the respective standard deviation, were selected as resistant.
Brachiaria decumbens cv. Basilisk was included as the susceptible check whereas Paspalum atratum cv. Pojuca,
and B. brizantha cv. Marandu, as the resistant ones.
Results and Discussion
The survival rates varied from 4 to 100%, the average being 38.9 ± 29.5% for the group. For nymphal
period, the variation was from 27.4 to 35.5 days, with an average of 30.6 ± 2 days (Fig. 1). In accordance with the
adopted screening criterion, only two genotypes (codes BRA10537 and BRA19186) were selected as more resistant
in this trial. The nymphal survivals for these genotypes were 5 and 6%; whereas the duration of the nymphal
periods were, 35.5 and 34.5 days, respectively. The genotype BRA19186 has been previously evaluated at Embrapa
Beef Cattle, confirming spittlebug resistance not only to N. entreriana but also to other spittlebug species (Valério
et al., 2005; 2013; Pistori et al., 2008). Presumably the resistance exhibited by these plants is due to secondary
chemicals, being still necessary, additional studies to fully understand the basis of this resistance. All the remainder
evaluated hybrids in the present trial provided intermediate to high percentages of nymphal survivorship, showing
suitableness as host plants to this spittlebug species. Those four Brachiaria hybrids were then selected as resistant
to the pasture spittlebug N. entreriana through the mechanism of resistance termed antibiosis, impairing
development and survival of the nymph.
Figure 1. Selecting genotypes of the genus Paspalum for resistance to the pasture spittlebug Notozulia
entreriana based on nymphal survival and duration of the nymphal period
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52a Reunião Anual da Sociedade Brasileira de
Zootecnia
Zootecnia: Otimizando Recursos e Potencialidades
Belo Horizonte – MG, 19 a 23 de Julho de 2015
Conclusions
Source of high levels of antibiosis to the pasture spittlebug Notozulia entreriana was found among
genotypes of the genus Paspalum. Considering that the data obtained in this experiment for the genotype
BRA19186 (P. regnellii) confirm high level of antibiosis; this plant, in relation to spittlebug resistance, holds great
potential to become a new Paspalum cultivar.
Acknowledgements
Financial support from EMBRAPA, CNPq, FUNDECT/MS and, UNIPASTO, is gratefully acknowledged.
References
Lapointe, S. L.; Serrano, M. S.; Arango, G. L.; Sotelo, G. and Cordoba, F. 1992. Antibiosis to spittlebugs
(Homoptera: Cercopidae) in accessions of Brachiaria. Journal Economic Entomology 85:1485-1490.
Pistori, M. G. B.; Valério, J. R.; Chermouth, K. da S. and Oliveira, M.C.M. 2008. Resistência de acessos da
gramínea forrageira do gênero Paspalum à cigarrinha Mahanarva fimbriolata (Hemiptera: Cercopidae). In: Anais
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