INVESTIGADORES
ZAVALA Jorge Alberto
artículos
Título:
Abnormally high digestive enzyme activity and gene expression explain the contemporary evolution of a Biabrotica biotype able to feed on soybeans
Autor/es:
CURZI, M.; ZAVALA J.A.; SPENCER, J.; SEUFFERHELD, M.
Revista:
Ecology and Evolution
Editorial:
Wiley-Blackwell
Referencias:
Lugar: Oxford; Año: 2012 vol. 2 p. 2005 - 2017
ISSN:
2045-7758
Resumen:
Western corn rootworm (Diabrotica virgifera) (WCR) depends on the continuous
availability of corn. Broad adoption of annual crop rotation between corn
(Zea mays) and nonhost soybean (Glycine max) exploited WCR biology to provide
excellent WCR control, but this practice dramatically reduced landscape
heterogeneity in East-central Illinois and imposed intense selection pressure.
This selection resulted in behavioral changes and ?rotation-resistant? (RR)
WCR adults. Although soybeans are well defended against Coleopteran insects
by cysteine protease inhibitors, RR-WCR feed on soybean foliage and remain
long enough to deposit eggs that will hatch the following spring and larvae will
feed on roots of planted corn. Other than documenting changes in insect mobility
and egg laying behavior, 15 years of research have failed to identify any diagnostic
differences between wild-type (WT)- and RR-WCR or a mechanism that
allows for prolonged RR-WCR feeding and survival in soybean fields. We documented
differences in behavior, physiology, digestive protease activity (threefold
to fourfold increases), and protease gene expression in the gut of RR-WCR
adults. Our data suggest that higher constitutive activity levels of cathepsin L are
part of the mechanism that enables populations of WCR to circumvent soybean
defenses, and thus, crop rotation. These new insights into the mechanism of
WCR tolerance of soybean herbivory transcend the issue of RR-WCR diagnostics
and management to link changes in insect gut proteolytic activity and
behavior with landscape heterogeneity. The RR-WCR illustrates how agroecological
factors can affect the evolution of insects in human-altered ecosystems.Diabrotica virgifera) (WCR) depends on the continuous
availability of corn. Broad adoption of annual crop rotation between corn
(Zea mays) and nonhost soybean (Glycine max) exploited WCR biology to provide
excellent WCR control, but this practice dramatically reduced landscape
heterogeneity in East-central Illinois and imposed intense selection pressure.
This selection resulted in behavioral changes and ?rotation-resistant? (RR)
WCR adults. Although soybeans are well defended against Coleopteran insects
by cysteine protease inhibitors, RR-WCR feed on soybean foliage and remain
long enough to deposit eggs that will hatch the following spring and larvae will
feed on roots of planted corn. Other than documenting changes in insect mobility
and egg laying behavior, 15 years of research have failed to identify any diagnostic
differences between wild-type (WT)- and RR-WCR or a mechanism that
allows for prolonged RR-WCR feeding and survival in soybean fields. We documented
differences in behavior, physiology, digestive protease activity (threefold
to fourfold increases), and protease gene expression in the gut of RR-WCR
adults. Our data suggest that higher constitutive activity levels of cathepsin L are
part of the mechanism that enables populations of WCR to circumvent soybean
defenses, and thus, crop rotation. These new insights into the mechanism of
WCR tolerance of soybean herbivory transcend the issue of RR-WCR diagnostics
and management to link changes in insect gut proteolytic activity and
behavior with landscape heterogeneity. The RR-WCR illustrates how agroecological
factors can affect the evolution of insects in human-altered ecosystems.Zea mays) and nonhost soybean (Glycine max) exploited WCR biology to provide
excellent WCR control, but this practice dramatically reduced landscape
heterogeneity in East-central Illinois and imposed intense selection pressure.
This selection resulted in behavioral changes and ?rotation-resistant? (RR)
WCR adults. Although soybeans are well defended against Coleopteran insects
by cysteine protease inhibitors, RR-WCR feed on soybean foliage and remain
long enough to deposit eggs that will hatch the following spring and larvae will
feed on roots of planted corn. Other than documenting changes in insect mobility
and egg laying behavior, 15 years of research have failed to identify any diagnostic
differences between wild-type (WT)- and RR-WCR or a mechanism that
allows for prolonged RR-WCR feeding and survival in soybean fields. We documented
differences in behavior, physiology, digestive protease activity (threefold
to fourfold increases), and protease gene expression in the gut of RR-WCR
adults. Our data suggest that higher constitutive activity levels of cathepsin L are
part of the mechanism that enables populations of WCR to circumvent soybean
defenses, and thus, crop rotation. These new insights into the mechanism of
WCR tolerance of soybean herbivory transcend the issue of RR-WCR diagnostics
and management to link changes in insect gut proteolytic activity and
behavior with landscape heterogeneity. The RR-WCR illustrates how agroecological
factors can affect the evolution of insects in human-altered ecosystems.