Doctoral Dissertations
Date of Award
12-1992
Degree Type
Dissertation
Degree Name
Doctor of Philosophy
Major
Plant, Soil and Environmental Sciences
Major Professor
Robert M. Hayes
Committee Members
John H. Reynolds, William A. Krueger, G. Neil Rhodes Jr, Otto J. Schwartz
Abstract
Field, greenhouse and laboratory experiments were conducted to investigate whole plant and cellular response of wild garlic to thifensulfuron-methyl.
Thifensulfuron-methyl activity on wild garlic was evaluated as influenced by rate and time of application, antagonism and sequential application. Phytotoxicity to small grains was also assessed. Thifensulfuron-methyl at 9 g ai ha⁻¹ was the lowest rate observed that suppressed aerial bulblet production greater than 90% when compared to the standard treatment of 2,4-D. Suppression was greatest at the 35 g ai ha⁻¹ applied in late March to early April. The lowest rate for reduction of underground bulbs was 35 g ai ha⁻¹ applied in late March.
Tank-mixing metribuzin at 210, 420 and 630 g ai ha⁻¹ with thifensulfuron-methyl antagonized the letter's activity on wild garlic aerial bulblet suppression. Reduction in underground bulb and aerial bulblet weight was antagonized by tank-mixing metribuzin with thifensulfuron-methyl. The antagonism of thifensulfuron-methyl only occurred for rates of 4 to 9 g ai ha⁻¹ and was totally overcome at 17.5 g ai ha⁻¹.
Sequential applications of thifensulfuron-methyl followed by metribuzin at 12 or 24 h or metribuzin followed by thifensulfuron-methyl at 12 or 24 h did not result in antagonized activity of thifensulfuron-methyl on wild garlic whole plant growth or aerial bulblet production. The lower rates of thifensulfuron-methyl followed at 12 h by metribuzin at 630 g ai ha⁻¹ was antagonized as evidenced by increases in underground bulb weights.
Thifensulfuron-methyl decreased bulb quality, shoot weight, number of roots per bulb and root and shoot length even at 4 g ai ha⁻¹ in the greenhouse. The addition of 420 g ai ha⁻¹ to all rates of thifensulfuron-methyl reduced the letter's ability to inhibit shoot growth. Thifensulfuron-methyl applied at rates up to 35 g ai ha⁻¹ was not phytotoxic to wheat or barley.
Thifensulfuron-methyl reduced shoot and root growth of aerial bulblets in sterile culture. The amino acids valine, leucine and isoleucine were inconsistent in overcoming the effects of thifensulfuron-methyl on aerial bulblet growth. All concentrations of thifensulfuron-methyl except 0.001 rag L⁻¹ inhibited growth of soft offset bulbs following 10 d of exposure. The addition of valine, leucine and isoleucine did not totally nullify the activity of thifensulfuron-methyl on soft offset bulb growth.
Recommended Citation
Oakes, John London, "Whole plant and cellular response of wild garlic (Allium vineale L.) to thifensulfuron-methyl. " PhD diss., University of Tennessee, 1992.
https://trace.tennessee.edu/utk_graddiss/7574