Velvetleaf theophrasti

A variety of chemicals may be leached from the aerial portions of plants by rainwater or by fog-drip (16) including organic acids, sugars, amino acids, pectic substances, gibberellic acids, terpenoids, alkaloids, and phenolic compounds. Colton and Einhellig (17) suggested that leaf leachates of velvetleaf (Abutilon theophrasti) may be inhibitory to soybean (Glycine maxT We have recently discovered specialized hairs on the stems of velvetleaf plants which exude toxic chemicals. 

Pigweed Amaranthus spp., foxtail Setaria spp., velvetleaf Abutilon theophrasti Medikus Carpetweed Mollugo verticillata L., common... 

Phenolic acids interfere with many major physiological processes of higher plants (35). These disruptions of function include an alteration of plant water balance. We found depression of leaf water potential to be an early indicator of allelochemical stress from ferulic and p-coumaric acids (42). Likewise one mechanism of allelopathic action by cultivated sunflower, velvetleaf Abutilon theophrasti Medic.), Koahia [Koahia saoparia (L.) Schrad.], and several other weeds was water stress (43-45). Since some allelochemicals interfere with plant-water relationships, it seemed logical that their action might be most critical at times when plants are under water stress from other causes. 

Sun JS, Foy CL (1996) Structurally related organosilicone surfactants, their physicochemical properties and effects on uptake and efficacy of primisulfuron in velvetleaf (Abutilon theophrasti Medicus). FRI Bulletin 193 225-230 (Proceedings of the fourth international symposium on adjuvants for agrochemicals, 1995)... 

Gronwald, J.W., R.N. Anderson, and C. Yee (1989). Atrazine resistance in velvetleaf (Abutilon theophrasti) due to enhanced atrazine detoxification. Pestic. Biochem. Physiol., 34 149-163. 

Andersen, R.N. and J.W. Gronwald (1987). Noncytoplasmic inheritance of atrazine tolerance in velvetleaf (Abutilon theophrasti). Weed Sci., 35 496 -98. 

Anderson, M.R and J.W. Gronwald (1991). Atrazine resistance in a velvetleaf (Abutilon theophrasti) biotype due to enhanced glutathione 5-transferase activity. Plant Physiol., 96 104-109. 

Gray, J.A., D.E. Stoltenberg, and N.E. Balke (1995a). Absence of herbicide cross-resistance in two atrazine-resistant velvetleaf (Abutilon theophrasti) biotypes. Weed Sci. 43 352-357. 

Begonia, M.F.T., Kremer, R.J. Chemotaxis of deleterious rhizobacteria to velvetleaf (Abutilon theophrasti) seeds and seedlings. FEMS Microbiol Ecol 1994 15 227-236. 

Owen, A., Zdor, R. Effect of cyanogenic bacteria on the growth of velvetleaf (Abutilon theophrasti) and corn (Zen mays) in autoclaved soil and the influence of supplemental glycine. Soil Biol Biochem 2001 33 801 -809. 

Colton, C. E. and Einhellig, F. A. 1980. Allelopathic mechanisms of velvetleaf (Abutilon theophrasti Medic., Malvaceae) on soybean. Amer. J. Bot. 67, 1407-1413... 

Several chemical herbicides were examined for efficacy on velvetleaf (Abutllon theophrasti Medic.) after placement in a dew chamber for 20 h at 25 C. Because many chemical herbicides have a label restriction that defines a drying time prior to exposure of herbicide-treated weeds to rainfall, drying time was varied prior to placement in a dew chamber. Bentazon [3-(l-methylethyl)-(lH)-... 

Greenhouse Bioassay. Sandy loam soil was treated with clomazone at rates ranging from 0.063 to 1.0 kg/ha and thoroughly mixed to incorporate the chemical into the soil. The bioassay was conducted by planting wheat (Triticum aestivum) and velvetleaf (Abutilon theophrasti) into the test soils and visually assessing plant injury in the form of bleaching (0 to 100 scale) 2 weeks after planting. 

Table 9.4 Specific Activity of Glutathione Transferase Isolated from Atrazine-Resistant (R) and -Susceptible (S) Biotypes of Velvetleaf (Abutilon theophrasti)...

In soils without a history of EPTC or butylate use, R251005 increased velvetleaf (Abutilon theophrasti Medic.), common cocklebur (Xanthium strumarium L.), and Pennsylvania smartweed (Polygonum pensylvanicum L.) control compared to EPTC alone (Table XI). In an EPTC history soil, Texas panicum (Panicum texanum L.) control was also increased (Table XI). 

Powell, R. G. and G. F. Spencer, Phytochemical inhibitors of velvetleaf (Ahutilon theophrasti) germination as models for new biorational herbicides, in Biologically Active Natural Products Potential Use in Agriculture (H. G. Cutler, ed.), ACS Symposium Series 380, 211-232, American Chemical Society, Washington, DC, 1988. 

Wolf, R. B., G. F. Spencer, and W. F. Kwolek, Inhibition of velvetleaf Abutilon theophrasti) germination and growth by benzyl isothiocyanate, a natural toxicant. Weed Sci., 32, 612-615 (1984). 

Trewiasine (13), from the seeds of Trewia nudiflora (Eu-phorbiaceae), gives greater than 50% inhibition of radicle elongation with velvetleaf Abutilon theophrasti) (Malvaceae) (Powell and Spencer, 1988). 

In addition to the 8 Ib/acre tests, several compounds with prominent preemergence activity were retested at either 0.12, 0.25, 0.5, or 1.0 Ib/acre on the following plant species, as well as the five species listed above barnyard grass (Echinochloa crusgalli), velvetleaf (AbutiIon theophrasti), wild oat (Ayena fatua), zinnia... 

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