Benzimidazole fungicides

Their development and commercial success was favoured by the coincidence of resistance to benzimidazole fungicides. 

M Hiemstra, JA Joosten, A De Kok. Fully automated solid-phase extraction cleanup on-line liquid chromatographic determination of benzimidazole fungicides in fruit and vegetables. J AOAC Int 78 1267-1274, 1995. 

Benzimidazole carbamates are usually analyzed by HPLC. Different stationary phases have been assayed, and alkyl-bonded-silica-based phases have generally been considered the most useful separation mode, although polymer-based columns performed better in separating benzimidazole fungicides (20). Buffered water and methanol (124,20) or acetonitrile (125) have been used as mobile phases. 

The much wider disease control spectrum of the benzimidazole fungicides (eg. benomyl, BCM, thiabendazole) - permitted far wider usage. In the beginning, these were suitable for control of numerous plant diseases, but a new phenomenon soon emerged - resistance Due to the specific mode of action of these fungicides, resistance could appear quite rapidly. The conventional fungicides previously used had a broad biocidal activity and resistance had never been experienced. 

The need for new fungicides for stone fruits has increased because of the development of benzimidazole-resistant Monilinla fructicola (8,9,30) and Coccomyces hiemalls (10) in important stone fruit production areas of the eastern United States. Resistance has been a major problem for stone fruit growers because alternative fungicides are less effective, more costly or require more frequent applications than benzimidazole fungicides. The recent registrations of iprodione and triforine for control of stone fruit diseases have helped to alleviate problems caused by benzimidazole resistance. 

Halko, R., C. Padron Sanz, Z. Sosa Ferrera, and J.J. Santana Rodriquez. 2004. Determination of benzimidazole fungicides by HPLC with fluorescence detection after micellar extraction. Chromatographia 60 151-156. 

Hine, R.B., Johnson, D.L., Wenger, C.J. (1969) Persistence of two benzimidazole fungicides in soil and their fungistatic activity against Phymatotrichum omnivorum. Phytopathology 59, 798-801. 

Uses Benomyl is a crystalline solid compound. It has little or no odor, and the USEPA has grouped it under GUP. Benomyl is a systemic benzimidazole fungicide that is selectively toxic to microorganisms and invertebrates, especially... 

All benzimidazole fungicides (benomyl, carbendazim, fuberidazole, thiabendazole) and thiophanate fungicides are cross-resistant. However, the reeently diseovered fungicide, zoxamide, which also inhibits the B-tubulin assembly, is not cross-resistant in oomycetes... 

Benzimidazoles have been applied rather more as herbicides, and in veterinary problems. There are, for example, many benzimidazole fungicides and herbicides, and the antihelimin-thics thiabendazole (197 R = H) and cambendazole (197 R = NHC02Pr ) are of proven efficiency both for human and veterinary use. There are also some fungicides known among the 2-aminoimidazolines. 

Chemicae/Pharmaceuticae/Other Ceass Benzimidazole fungicide... 

Mull RL and Hershberger LW (2001) Inhibitors of DNA biosynthesis-mitosis Benimidizoles - the benzimidazole fungicides benomyl and carbendazim. In Krieger R (ed.) Handbook of Pesticide Toxicology, 2nd edn., pp. 1673-1699. San Diego, CA Academic Press. 

Benzimidazole fungicides (Figure 1) are in wide use, as they are highly effective against various diseases present in commercially important crops. However, the intense, continuous use of... 

Some years ago, two groups of compounds, i.e. If-phenylcarbamates and N-phenylformamidoximes were synthesized in Japan and their specific antifungal activity against benzimidazole-resistant strains was reported ( 2, 3J. In France, where benzimidazole-resistant strains of the gray mold Botrvtis cinerea predominate in some areas, a N-phenylcarbamate compound diethofencarb is already in use as a mixture with a benzimidazole fungicide carbendazim. 

Benzimidazoles. Thiabendazole, and a few years later, benomyl, were introduced as postharvest fungicides 1n the late 1960s. These outstanding compounds (benzimidazole fungicides) provided excellent control of both fruit decay and Penicmium sporulation (1,2). 

Virtually all benzimidazole-resistant isolates of Penicilllum are cross-resistant to all other benzimidazole fungicides (7,8,13,14). Furthermore, many of these isolates show resistance also to the unrelated postharvest fungicides, SOPP, biphenyl, sec-butylamine, and guazatine (13,14,17,18). Multi-resistant biotypes apparently emerged from a benzimidazole-resistant population that was subjected to the selection pressure of the unrelated fungicides. 

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