Influence of benzimidazole fungicides on growth and foliar element accumulation of Agrostis palustris Huds. and Poa pratensis L.

Abstract

The effect of two benzimidazole fungicides, 2-(4-thiazolyl) benzimidazole (thiabendazole) and methyl l-(butylcarbamoyl)-2-benzimidazole carbamate (benomyl) on growth and foliar element accumulation of 'Penncross' and 'Seaside' cultiyars of. Agrostis palustris Huds. and 'Merion' cultivar of Poa pratensis L: was investigated ina series ,of greenhouse and field plot experiments. In the greenhouse, soils.with varying concentrations of the materials were seeded. with 'Penncross,' and 'Merion.In the field a 2 year old plant ing of the 'Seaside' cultivar (Agrostis palustris) was sprayed with thiabendazole, and benomyl formulations. Criteria employed for determining growth effectswere dry weight of foliage, dry weight of roots, and macro-and micro-element accumulation by the. foliage, Dry foliar weights of both Poa and Agrostis were increased by soil amendment with benomyl and thiabendazole, With Agrostis benomyl soil amendment increased foliar Κ and decreased P, Ca, Mg, Mn, B, and Na.Thiabendazole amendment increased Κ while decreasing Mg, Μn, and Na.In the field repeated foliar spray applications of benomyl increased Κ and Mg and decreased Cu and B.

Yield and Biochemical Response of Sugarbeet to Benomyl1

“…Although the inorganic constituents determined (Na+, K+, and CI-) appeared to decrease slightly under benomyl 1treatment, these decreases were not statistically significant. Other evidence confirms that alterations in some aspect of plant chemical composition can result from foliar application ofbenomyl (Warren et al, 1974:, Milosavljevic et al, 1975Joblin and Keogh, 1979;Tsvetkov and Zhilinskii, 1981 ).…”

“…Although we recognized that benomyl treatment might induce physiological effects, our decision to use the fungicide for our control treatment was based on the findings of Hanker and Kudelova (1976) whoreported no significant effect of benomyl at piant protectant levels on sugarbeet photosynthesis or on transport of 14 C labelled assimilate from leaf to root, and on the fact that there were no reports of benomyl effects on yield or chemical composition of disease-free sugarbeets. Subsequently, however, we noted occasional but accuumulating reports in the literature of measurable benomyl effects on some aspect of growth or yield in other crops (Cole et al, 1970;Warren et al, 1974;Milosavljevic et al, 1975;Griffiths and Scott 1977;Joblin and Keogh, 1979;Tripathi et al, 1980;Wtlkins, 1980). This led us to question our original hypothesis that there would be no effect on sugarbeet yield or chemical composition due to application of low doses ofbenomyl.…”