Nitidulid beetles infesting California dates

Abstract

California desert region has suitable temperatures for growing dates, producing' all but 10 per cent of the United States crop. This crop rose from 1 million pounds in 1926 to 33 million pounds in 1946, just twenty years later (Nixon, 1951). In 1924 a total of 546 acres was planted to dates; in 1950 this had increased to 5,114 acres, of which 4,140 acres were bearing' (Byrd and Blair, 1951). In the same period a tremendous increase took place in acreage of other crops grown in the date-producing' region. Irrigation projects now being' completed along the lower Colorado River are resulting' in an even greater expansion of agriculture in this area. Nitidulid beetles also find the Coachella Valley temperuture suitable for rapid gTo\vth and reproduction except for a f'ew winter months. Because of beetle infestation all dates are fumigated before entering the packing house. This necessitates the building of fumigation chambers, Uuder conditions of severe infestation, grading costs mount because of the added time necessary to segregate the infested dates from the sound ones. Although the larvae and adults feed directly on the fresh and dried fruit, the loss due to the amount of fruit actually consumed is insignificant in comparison with the loss due to the presence of excreta, larvae, adults, and the moulting skins in and on the infested dates. In many instances these dates are very difficult to segregate because there is no visible indication that the insects or their remains may be in the seed cavity. These are termed "hidden culls" by the industry. The beetles also serve as mechanical carriers of mold and souring organ-iS1l1S, which cause additional fruit spoilage. In 1945, a year of abnormally high humidity and rainfall, one half to three fourths of the date crop was lost because of molds, souring, and beetle infestation (Barnes and Lindgren, 1946). This paper is concerned with the four species of beetles that predominate on dates in the Coachella Valley. The four species, closely related members of the family Nitidulidae, are the corn-sap beetle, Carpophilus dimidiatus (Fab.); the dried-fruit beetle, C. h.emipterus (Linn.)-also called fig-or two-spotted beetle; the pineapple beetle, Urophorus humeralis (Fab.) ; and the yellowish nitidulid, Ho.ptoncus Luieolus (Er.).

Chemical characterization of fruit and fungal volatiles attractive to dried-fruit beetle,Carpophilus hemipterus (L.) (Coleoptera: Nitidulidae)

“…For example, in dates, Carpophilus spp. were found preferentially in those fruits that were infested with fungi (Lindgren and Vincent, 1953). C. hemipterus is a transmitting agent of fig smut caused by Aspergillus niger (Caldis, 1930) and has been incriminated as a vector of brown rot in stone fruits and pome fruits, as well (Tate and Ogawa, 1975).…”

The khapra beetle,Trogoderma granariumEverts

“…humidities. The methods used in these tests were similar to those used by Lindgren and Vincent (1953) on nitidulid larvae and adults.…”

Behavior of Carpophilus hemipterus in a vertical flight chamber: transition from phototactic to vegetative orientation

“…Nitidulidae, commonly referred to as sap beetles, feed on decaying fruit and vegetables (Lindgren & Vincent, 1953;Miller & Mrak, 1953;Windels et al, 1976), on fungal mats under bark (Neel etal., 1967;Hinds, 1972), on carrion (Abbott, 1937), and on a variety of flowers (Gazit et al, 1982;Nagel et al, 1989). While the majority of nitidulid species perform beneficial roles as detritivores, predators or pollinators, a few species are pests because they have been implicated in the transmission of oak wilt disease (Ceratocystis fagacearum (Bretz)) (Dorsey & Leach, 1956;Juzwik & French, 1986), corn ear rot (Fusarium sp.)…”