Plant protecting and regulating compositions – Plant growth regulating compositions – Micro-organisms or from micro-organisms
Reexamination Certificate
2000-08-03
2001-08-14
Clardy, S. Mark (Department: 1616)
Plant protecting and regulating compositions
Plant growth regulating compositions
Micro-organisms or from micro-organisms
Reexamination Certificate
active
06274534
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
Kudzu (
Pueraria lobata
) is a perennial leguminous vine introduced from Japan that produces a large starchy tuber-like root system. Now infesting over 7 million acres of the southeastern United States, and spreading at a rate of 120,000 acres per year, this plant represents a serious threat to productivity in its growing region.
This invention relates to novel methods for the control of kudzu based upon the application of conidia of
Myrothecium verrucaria
in herbicidally effective amounts. These methods, due to their systemic nature, do in fact provide superior control of the weed as compared to known commercial alternatives.
2. Description of the Prior Art
Several methods are known in the art for using microorganisms to control weeds and other pest plants. As disclosed in U.S. Pat. No. 3,999,973 (Daniel et al.), the anthracnose fungus
Colletotrichum gloeosporiodes
has been used to control the weed northern jointvetch and another strain of the fungus has been used to control winged waterprimrose.
Colletotrichum malvarum
has been used to control prickly sida. These three pathogens have been combined to control all three target weeds at once. In other experimental work, the fungus
Alternaria macrospora
has been used to control spurred anoda (
Anoda cristata
) [H. L. Walker,
Weed Science
, Vol.29, pp.505-507, 1981].
Research activity involving
M. verrucaria
is noted on page 8 of the IBG News, Vol.4, No. 1, May 1995 issue. U.S. Pat. No. 4,390,360 (Walker), describes “Control of Sicklepod; Showy Crotaria and Coffee Senna With a Fungal Pathogen” using a specific host strain of the fungus
Alternaria cassiae
to produce typical weed lesions which kill or suppress the respective weeds. U.S. Pat. No. 4,419,120 (Walker), discloses “Control of Prickly Sida, Velvetleaf, and Spurred Anoda With Fungal Pathogens” using a specific host strain of the fungus
Fusarium lateritium
to kill or suppress the respective weeds. U.S. Pat. No. 4,715,881 (Andersen et al.), details “Control of Eastern Black Nightshade With a Fungal Pathogen” using a strain of
Colletotrichum coccodes
which is pathogenic towards eastern black nightshade (
Solanium prycanthum
). U.S. Pat. Nos. 4,718,935 and 4,767,441 (Walker et al.), describe a “Method for the Preparation of Mycoherbicide-Containing Pellets” characterized by alginate gel pellets containing living fungus capable of producing conidia when exposed to sufficient light and moisture. U.S. Pat. Nos. 4,724,147 and 4,818,530 (Marois et al.), detail the “Preparation of Pellets Containing Fungi for Control of Soilborne Diseases”, in which fungi are first selected and grown for a time sufficient to produce inoculum. The fungal propagules are harvested, homogenized and diluted with sodium alginate solution. Pelletization is then accomplished by dropwise addition of the fungal propagule-alginate mixture into a solution of calcium chloride or calcium gluconate. The resulting alginate gel pellets containing living fungi can then be dried and used to inoculate agricultural fields infested with soilborne plant diseases. U.S. Pat. No. 5,192,541 (Savage et al.), describes “Weedkilling
Xanthamonas campestris
”, in which novel microorganisms useful in controlling unwanted grasses and other weeds are discovered through a unique process which involves isolating plant pathogens from asymptomatic plants. U.S. Pat. No. 5,393,728 (Charudatten et al.), details a “Broad Spectrum Bioherbicide to Control Several Species of Pigweeds”, in which a novel Phomopsis sp. fungus is used as an effective broad-spectrum bioherbicide for controlling pigweed.
U.S. Pat. No. 5,747,029 (Walker et al.), hereby incorporated by reference, teaches methods for the biological control of various weeds including sicklepod, pigweed, spurred anoda, jimsonweed, and hemp sesbania using the fungus
M. verrucaria
. This work, while showing that
M. verrucaria
is effective in controlling a number of varieties of weeds in several different types of important agricultural crops, shows that effective control of a given species is more the exception than the rule and that the host range for this fungus was not predictable (Col. 2, lines 66-67). Effective control, where it occurred, also required the presence of a dew period. The prior art as a whole teaches that fungi developed as biological herbicides should be restricted in host range to a limited number of plant species.
SUMMARY OF THE INVENTION
We have now discovered means for the effective biological control of kudzu (
Pueraria lobata
) using the fungus
M. verrucaria
. The fungus is isolated, produced, compositioned and applied to kudzu by methodology taught in U.S. Pat. No. 5,747,029 (Walker et al.), which is herein incorporated by reference.
In accordance with this discovery, it is an object of the invention to provide means for the effective biological control of kudzu.
Other objects and advantages of the invention will become readily apparent from the ensuing description.
DEPOSIT OF BIOLOGICAL MATERIAL
M. verrucaria
(Alb. and Schwein) Ditmar ex Fr. is on deposit with the Department of Biological Sciences, Louisiana Tech University in Ruston, La., at the United States Department of Agriculture, Agricultural Research Service, Southern Weed Science Research Unit in Stoneville, Miss.; and was placed on deposit with the International Mycological Institute, Bakeham Lane, Egham Surrey, UK, on May 18, 1994, as IMI number 361690. The deposit was placed in the patent collection of the International Mycological Institute on Jun. 21, 1995, under the terms of the Budapest Treaty, and has been assigned accession number IMI 368023.
According to M. Tulloch, (The Genus Myrothecium Tode ex Fr.
Mycologiical Papers
130, 1-42, 1972),
M. verrucaria
is described as follows: “Spore mass wet, black, convex surrounded by wet floccose margin. Spores broadly fusiform, one end pointed the other protruding and truncate, in erythrosin and NH
4
solution with a fantailed appendage on the pointed end, 6.5-8×2.3-5 microns.”
The
M. verrucaria
used in this invention was isolated from diseased plants of sicklepod, a new host record for this fungus.
DETAILED DESCRIPTION OF THE INVENTION
The fungus may be cultured by conventional means, such as those disclosed in U.S. Pat. No. 5,747,029 (Walker), hereby incorporated by reference. Conidia produced are then formulated in aqueous solution and compositioned with a surfactant such as Silwet L-77 (trademark); a silicone-polyether copolymer spray adjuvant, OSI Specialties, Inc., Charlotte, N.C. Other useable surfactants include Tween-20 [oxysorbic (20 POE) (polyoxyethylene sorbitan monooleate)], Tween-80 (Polysorbate 80) and Sterox [nonoxynol (9 to 10 POE) [a-(p-onylphenyl)-w-hydroxypoly(oxyethylene)]]. Useable compositional concentrations of the conidia range from about 2×10
6
to about 2×10
8
conidia/ml of solution, with the surfactant being present in amounts ranging from about 0.02% to about 0.4% (vol/vol), preferably about 0.1 to about 0.3% (vol/vol). Application is made to the kudzu at a rate ranging from about 5 to about 100 gallons per acre, preferably about 40 to about 60 gallons per acre. Effective control of the kudzu is herein defined as achieving a biocidal rate of 90% or greater within 14 days of application. Efficacy does not require the presence of a dew period as indicated by growth chamber and greenhouse tests, and is similarly tolerant under field conditions to temperatures up to about 40° C.
The experimental parameters used in examples cited for this invention are not intended to limit the scope of this invention. Modification of factors such as inoculum concentrations, parameters for inoculum production, surfactants, application methods, and other factors, would be expected to influence efficacy of this invention. Parameters were selected to enable detection of interactions, to document the relationship of this invention to the prior art, and to illustrate that the unique and surprising characteristics o
Abbas Hamed K.
Boyette Clyde D.
Walker Harrell L.
Clardy S. Mark
Fado John D.
Lipovsky Joseph A.
Silverstein M. Howard
The United States of America as represented by the Secretary of
LandOfFree
Control of kudzu with a fungal pathogen derived from... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Control of kudzu with a fungal pathogen derived from..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Control of kudzu with a fungal pathogen derived from... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2485396