EFFECTS OF CARBOFURAN ON ARTHROPOD POPULATIONS AND CROP YIELD IN HAYFIELDS

1972 ◽  
Vol 104 (9) ◽  
pp. 1433-1437 ◽  
Author(s):  
C. D. Dondale

AbstractCarbofuran was applied to three hayfields at a rate of 0.56 kg/ha in early June. This caused significant reductions of Thysanoptera, phytophagous Coleoptera larvae (including the alfalfa weevil, Hypera postica (Gyl.)), and Cicadellidae. It caused similar reductions in Araneida and parasitoids. The differences between treated and untreated plots were no longer significant by September. Carbofuran did not significantly affect the yield of air-dried hay or of crude protein.

2004 ◽  
Vol 39 (4) ◽  
pp. 598-610 ◽  
Author(s):  
Hayes B. Goosey ◽  
Patrick G. Hatfield ◽  
Sue L. Blodgett ◽  
S. Dennis Cash

Fall regrowth of alfalfa, Medicago sativa (L.), serves as a major source of winter pasture for Montana sheep producers. In years of drought, alfalfa fields are extensively winter/spring grazed; however, the impact on crop health is unknown. Alfalfa paddocks were continuously grazed for 95 d in 2002 and 98 d in 2003 during winter and spring to determine the impact on spring and summer alfalfa regrowth, nutrient quality characteristics, and alfalfa weevil, Hypera postica Gyllenhal, densities. Grazed and non-grazed forage yield, crude protein (%), and acid and neutral detergent fibers (%) did not differ at harvest (P> 0.17) during either study year. Acid and neutral detergent fibers (kg/ha) were greater (P < 0.05) in non-grazed compared to grazed plots during 2002–2003. Alfalfa weevil densities were lower in grazed than non-grazed plots (P< 0.03) over four sampling dates during both study years. Winter/spring sheep grazing appears to offer potential for alfalfa weevil management without compromising yield or nutritive factors of subsequent alfalfa production.


2000 ◽  
Vol 35 (2) ◽  
pp. 129-135 ◽  
Author(s):  
Sue L. Blodgett ◽  
Andrew W. Lenssen ◽  
S. Dennis Cash

Successful implementation of early harvest techniques for alfalfa weevil larval, Hypera postica Gyllenhal, management depends on synchronization between alfalfa growth sufficient for harvest and economic populations of the insect, conditions that frequently occur in Montana. Field trials were conducted in 1996 and 1997 to determine if the addition of raking to timed harvest would improve the efficacy of alfalfa weevil larvae management, an important cultural control of alfalfa weevil larval populations. Post-baling mean number of alfalfa weevil larvae in stubble were 4.3 (SE = 1.6) and 7.5 (SE = 1.1) per 0.1 m2 for cutting with raking and cutting alone, respectively, (P = 0.06). Nutritive value of forage, as estimated by crude protein and neutral and acid detergent fiber concentrations, did not differ between treatments. Harvest combined with early raking effectively reduced alfalfa weevil larvae populations over cutting alone without compromising nutritive value of forage.


1991 ◽  
Vol 123 (1) ◽  
pp. 197-203 ◽  
Author(s):  
Christopher M. Maund ◽  
T.H. Hsiao

AbstractEncapsulation of Bathyplectes curculionis (Thomson) and B. anurus (Thomson) (Hymenoptera: Ichneumonidae) was investigated by dissecting parasitized larvae of three strains of the alfalfa weevil, Hypera postica (Gyllenhal) (Coleoptera: Curculionidae). In laboratory studies, there was no encapsulation of B. curculionis in the western strain of the weevil, a significant level of encapsulation in the eastern strain of the weevil, and nearly complete encapsulation in the Egyptian strain of the weevil. The rickettsia, Wolbachia postica Hsiao and Hsiao, found only in the western strain, was not involved in encapsulation. Variation in encapsulation was due to biological differences between weevil strains. Encapsulation rates among field populations of the western and Egyptian weevils were lower than in the laboratory. Encapsulation rates of weevil populations from zones in which western and Egyptian strains overlap in southern Utah, and between eastern and western strains in Colorado, were intermediate to rates of parental strains. These results imply that B. curculionis effectiveness against the western alfalfa weevil will decline with mixing of weevil strains. Bathyplectes anurus did not evoke encapsulation and was able to develop equally well in all three weevil strains. Our findings illustrate the importance of investigating the compatibility between alfalfa weevil strains and their parasitoids in devising a sound biological control strategy.


2005 ◽  
Vol 137 (4) ◽  
pp. 488-491
Author(s):  
Qodrat Sabahi ◽  
Khalil Talebi

The alfalfa weevil, Hypera postica (Gyllenhal) (Coleoptera: Curculionidae), can severely damage the first cutting of alfalfa, Medicago sativa L. (Fabaceae), in much of Iran. The pest has been parasitized by several parasitoids including Oomyzus incertus (Ratzeburg) (Hymenoptera: Eulophidae), a gregarious larval endoparasitoid. This wasp can parasitize up to 30% of weevil larvae in alfalfa fields in northern Iran. It produces three to four generations per year, and the female prefers the fourth instar of the host for oviposition. Each female lays 2 to 22 eggs per host, which hatch within 47–60 h. The life cycle is completed in about 2 weeks, upon pupation inside the host. This species is predominantly present during the summer months in alfalfa fields (Streams and Fuester 1967).


2008 ◽  
pp. 110-110
Author(s):  
George Hangay ◽  
Severiano F. Gayubo ◽  
Marjorie A. Hoy ◽  
Marta Goula ◽  
Allen Sanborn ◽  
...  

1976 ◽  
Vol 108 (6) ◽  
pp. 649-654
Author(s):  
G. A. Surgeoner ◽  
C. R. Ellis

AbstractCarbofuran at 2 oz AI/acre caused a 94% reduction in 3rd- and 4th-instar larvae of alfalfa weevil. There was a 67% reduction in 1st- and 2nd-instar larvae which were protected within the buds. Carbofuran did not reduce the percentage parasitism by Bathyplectes curculionis (Thomson) although the total parasitoids that developed per unit area was less.


1960 ◽  
Vol 53 (1) ◽  
pp. 178-179 ◽  
Author(s):  
George O. Poinar ◽  
George G. Gyrisco

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