Hypera brunnipennis, the Egyptian
alfalfa weevil, is a true weevil in the family Curculionidae. The name is sometimes
found spelled in the literature as Hypera brunneipennis
or Pytonomus brunneipennis
Boheman. The weevil adults are light
brown with dark brown and grey markings on their backs and are about 0.2
inches long. Adult also emerge from a
summer aestivation in late autumn or winter and migrate to alfalfa fields to
feed, mate and lay eggs. Females
chews openings in the plant stem where eggs they lay eggs. The eggs may be laid in living or dead stems near the soil
surface or in plant fragments on the ground.
Eggs will hatch in five to ten days depending on the temperature. The hatched larvae are very small
legless. Their color is greenish and they
attain a length of only one-quarter inch when grown, and their color assumes
a lighter green with a whitish strip on their back. The head is dark brown to black.
The weevils feeds on
alfalfa plant terminals of the first growth after winter. This feeding does not cause much damage to
alfalfa but produces stem scars.
However, later the larvae begin to feed on terminal buds and leaves
and slowly move down the plant feeding on young developing leaves. Succeeding instar larvae cause the most
damage by feeding on interveinal alfalfa leaf tissue, skeletonizing,
bronzing, and subsequently defoliating plants, which of course reduces
photosynthsis and the damage to regrowth buds can stunt growth and kill
alfalfa stems. Most damage usually
occurs under field windrows because harvesting moves weevil larvae under cut
hay where they feed on new growth.
There is considerable damage to the first and sometimes to second and
third hay cuttings.
Ongoing biological control research
involves both insect parasitic and predatory species and entomopathogenic
fungi.
REFERENCES:
Amira, A. Ibrahim & A. H. El-Heneidy. 1981. Immature stages of Bathyplectes curculionis Thoms.
(Hymenoptera: Ichneumonidae). Res.
Bull 1544, July 1981, Ain Shams University, Fac. of Agric., Cairo, Egypt.
El-Sherif, S. I., M. F. S. Tawfik & A. H. El-Heneidy. 1978. The biology of the Egypt alfalfa weevil, Hypera brunneipennis Boh. (Coleoptera, Curculionidae).
Beitrage Trop. Landwirt. Veterinarmed. 16 (1): 79-89, Germany.
Gonzalez, D., L. Etzei, M. Esmaili,
A. H. El-Heneidy & I. Kaddou. 1980. Distribution of Bathyplectes curculionis and Bathyplectes
anurus (Hym.: Ichneumonidae) from Hypera (Col.: Curculionidae) on alfalfa
in Egypt, Iraq and Iran. Entomophaga 25
(2): 111-121, France.
Hassanein, Fawzia A. & A. H. El-Heneidy. 1988. Comparative study of the parasitism by Microplitis rufiventris Kok.
(Hymenoptera: Braconidae) and Periboae
orbate Wied. (Diptera: Tachinidae) on main lepidopterous pests in
vegetable crop fields in Egypt. Bull.
Soc. Ent. Egypte, Econ. Ser. 17: 127-135.
Smetana, A., eds. 2013. Catalogue of Palaearctic Coleoptera,
Volume 8: Curculionoidea II. Apollo
Books. ISBN 978-90-04-25916-4.
El Husseini, M. M. M. 2019. Management
of the Egyptian alfalfa weevil, Hypera
brunneipennis (Boheman) (Coleoptera: Curculionidae), in the
alfalfa, Medicago sativa L.,
using the entomopathogenic fungus, Beauveria
bassiana (Balsamo) Vuillemin. Egypt J. Biol. Pest Control 29: 82.
El-Sheikh, W. E. A. 2019.
Population Dynamics and Seasonal Development of the Egyptian Alfalfa
Weevil, Hypera brunneipennis
(Boh.), (Coleoptera: Curculionidae) in El-Farafra Oasis, New Valley
Governorate, Egypt. J. Plant Prot.
and Path., Mansoura Univ. 10(6):
311-316.
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