Grasses growth inhibition

According to the investigations of Moreland (1969) terbutol inhibits the growth of roots and rhizomes at the terminal meristems. Root growth of seedling grass is inhibited—leaves become deformed and do not grow. These symptoms indicate that terbutol, like other carbamates, is a mitosis poison. 

The inhibiting effect on grass growth of propham, the first active representative of the chemically related carbamate compounds was recognised as early as 1941, but the herbicidal action of the thiocarbamate group was discovered much later. 

Sensitive grass weeds rapidly absorb alloxydim-sodium, which is then rapidly translocated apoplastically and symplastically. Growth inhibition, chlorosis, antocyanide formation are manifested by the treated plant, and finally, necrotic wilt. The biochemical mode of action of the herbicide is not yet precisely known (Iwataki and Hirono, 1978). 

Inhibition of root growth in wheat caused by the grass herbicide haloxyfop [2-(4-[(3-chloro-5-trifluoromethyl)2-pyridinyl)oxo]phenoxy)propanoic acid) is accompanied by a relative increase in linolenate in the membrane lipids of the root tips (Banas et aL, 1993a). A number of substances which counteract the growth inhibition also counteract the increase in linolenate (Banas et aL, 1993b). In order to elucidate possible relationship between these antagonistic compounds and their effect on polyunsaturated fatty acid content, we report in this communication the effect of two of these substances, salicylic acid (SAL) and salicylhydroxamic acid (SHAM), on the production of polyunsaturated fatty acids in vivo and in vitro,... 

Cineoles are monoterpenes present in the essential oils of many aromatic plants (e.g. Laurus nobilis L., Salvia spp., Eucalyptus spp., Xanthoxylum rhetsa D. C., and Artemisia spp). Many classes of volatile monoterpenes inhibit plant growth (e.g. [36]). Growth inhibition of grasses by volatile monoterpenes released by Salvia leucophylla is most effective during seedling development and establishment [6]. 

DCPA inhibits the growth of grass species by dismpting the mitotic sequence, probably at entry (190). DCPA influences spindle formation and function (181) and causes root-tip swelling (182) and britde shoot tissue (191). It has been reported that DCPA, like colchicine and vinblastine, attests mitosis at prometaphase and is associated with formation of polymorphic nuclei after mitotic arrest (192). Pronamide also inhibits root growth by dismpting the mitotic sequence in a manner similar to the effect of colchicine and the dinitroanilines (193,194). Cinmethylin and bensuhde prevent mitotic entry by unknown mechanisms (194). 

Figure 3. Histograms showing growth response of cress, barnyard grass, and cucumber to 347 microbial isolates bioassayed on solid medium. Growth response 1) seedling growth minimal or germination nil, 2) pronounced inhibition, 3) slight inhibition, 4) growth comparable to controls, 5) stimulation over controls.

Weston LA, Putnam AR (1985) Inhibition of growth nodulation, and nitrogen fixation of legumes by quack grass. Crop Sci 25 561-565... 

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