Biological effects of the free and embedded metribuzin and tribenuron-methyl herbicides on various cultivated weed species

Abstract

The present study addresses the herbicidal activity and biological effects of the metribuzin (MET) and tribenuron-methyl (TBM) herbicides used to control various weed species (Amaranthus retroflexus, Sinapis arvensis, and Leucanthemum maximum). The effects of the free herbicides and the herbicides embedded in granules of degradable polymer poly-3-hydroxybutyrate [P(3HB)] blended with birch wood flour were compared. Metribuzin, regardless of the form, caused 100% mortality of the three weeds by day 21. The herbicidal activity of tribenuron-methyl was lower than that of metribuzin, but the embedded TBM was superior to the free herbicide in the length and strength of its action on the weeds. Both metribuzin forms dramatically decreased the main parameters of fluorescence: maximum quantum yield of photosystem-II [Y(II) max ], maximum quantum yield of non-photochemical quenching [Y(NPQ) max ], and maximum rate of non-cyclic electron transport [ETR max ] and concentrations of chlorophyll a and b. The effect of the embedded TBM on the photosynthetic activity of the weeds was lower in the first two weeks of the growth of herbicidetreated plants but lasted longer than the effect of the free TBM and increased over time. Embedding of metribuzin in the matrix of degradable blend did not decrease its herbicidal activity.

Effectiveness of slow‐release fungicide formulations for suppressing potato pathogens

“…In order to reduce the cost of such formulations and make them easily accessible, pesticides were embedded not only into the very expensive pure P(3HB) but also into the polymer filled with inexpensive natural materials (clay, peat, wood flour). The efficacy of formulations was confirmed in vegetable and cereal crops infested by weeds and infected by root rot pathogens 34–41 …”

“…The efficacy of formulations was confirmed in vegetable and cereal crops infested by weeds and infected by root rot pathogens. [34][35][36][37][38][39][40][41] Potato is one of the few industrially significant crops that reproduces vegetatively, is affected and accumulates pathogens in vegetative generations: viruses, bacteria, and fungi. The main source of infection is carbohydrate-rich tubers, which serve as a substrate for the development of pathogenic microorganisms that cause various diseases of this crop.…”

Comparative proteomic and physiological analyses reveal tribenuron‐methyl phytotoxicity and nontarget‐site resistance mechanisms in Brassica napus

“…Tribenuron‐methyl (TBM) is a postemergence herbicide belongs to the SU family and can effectively protect crops from both grass and broadleaf weeds (Volova et al, 2020). Despite the weed control successes with TBM in the field, its application is restricted since conventional rapeseed varieties are susceptible to SU herbicides and development of SU‐resistant rapeseed varieties might be an efficient way to solve this problem (Guo et al, 2020).…”