Download or read book The Biology and Control of Hydrilla Verticillata L f Royle written by Adam J. Cauldwell and published by . This book was released on 1982 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Biological Control of Hydrilla Verticillata L f Royle with Lytic Enzyme producing Microorganisms written by Judith C. Pennington and published by . This book was released on 1985 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hydrilla Hydrilla Verticillata L F Royle written by Kenneth A. Langeland and published by . This book was released on 1990 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Aquatic Plant Control Research Program Biological Control of Hydrilla Verticillata L f Royle with Lytic Enzyme Producing Microorganisms written by Judith C. Pennington and published by . This book was released on 1985 with total page 45 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bacteria and fungi isolated from the microsphere of hydrilla were screened for production of the lytic enzymes cellulase and pectinase. Lytic enzyme-positive isolates were successively subcultured on restrictive media in the laboratory to enhance enzyme production. Twenty-two of the enzyme-enhanced isolates were assayed using hydrilla sprigs in test tubes to determine their ability to infect the plant. Seven cellulase-producing fungi produced significantly greater damage to hydrilla than exhibited by treated or untreated controls. Six of these were assayed using hydrilla plants in 75.7-l aquaria. None of the fungi significantly damaged hydrilla in the aquaria. Inoculum for the aquarium assay consisted of filtered organisms, whereas whole inoculum including nutrient growth medium (PDB) and accumulated exogenous metabolites (e.g. cellulase) was used in the preliminary test tube assay. This difference in inoculum for the two assays and the negative results of the aquarium assay suggested that the isolates required nutrient or metabolite supplements in the inoculum to inflict damage on hydrilla. Results showed that whole inoculum produced significantly greater damage than filtered organisms and that nutrients must be present for the organisms to impact hydrilla. Results of the two assays also showed that greenhouse plants were more resistant to attack than field plants.

Download or read book Evaluation of Fungi for Biological Control of Hydrilla Verticillata L f Royle written by Gary F. Joye and published by . This book was released on 1989 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Aquatic Plant Control Research Program Chemical Control of Hydrilla in Flowing Water Herbicide Uptake Characteristics and Concentrations Versus Exposure written by Thai K. Van and published by . This book was released on 1988 with total page 51 pages. Available in PDF, EPUB and Kindle. Book excerpt: Most alternative techniques for management of hydrilla (Hydrilla verticillata (L.f.) Royle) have been developed for lentic systems, and thus their use in flowing water is usually limited. Control of hydrilla in flowing water is difficult because the herbicide may be in contact with the plant for a matter of hours or minutes before being swept away by the current. This study was conducted to develop strategies for hydrilla control in flowing water. Specific objectives were: (a) to determine the susceptibility of the monoecious hydrilla to registered aquatic herbicides, (b) to provide information on the minimum contact time required for control of monoecious and dioecious hydrilla with diquat, endothall, and fluridone, and (c) to examine time-course uptake characteristics of these herbicides by hydrilla. All results presented in this report were from laboratory studies and should be verified and field trials in natural environments. Keywords: Aquatic plants; Weed control; Marine biology; Herbicides; Diquat; Endothall; Fluridone.

Download or read book Genetic Structure of Hydrilla Verticillata L f Royle in Eastern China and the Republic of Korea written by Dean A. Williams and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Invasion Biology of Hydrilla Verticillata Lf Royle in New Zealand written by Deborah Ellen Hofstra and published by . This book was released on 1997 with total page 598 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluation of Fungi for Biological Control of Hydrilla Verticillata L f Royle written by Gary F. Joye and published by . This book was released on 1989 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Growth and Rooting Depth Characteristics of Hydrilla Verticillata L f Royle and Myriophyllum Spicatum L on Fertilized and Unfertilized Sediments written by Dwilette G. McFarland and published by . This book was released on 1994 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Managing Hydrilla Field Trials Using Biological and Chemical Control Technologies Alone and in Combination written by and published by . This book was released on 1999 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This technical note describes the results of two field studies to evaluate the effectiveness of a granular formulation of the fungal pathogen Mycoleptidiscus terrestris (Gerd.) Ostaseski (Mt), against the noxious aquatic weed, hydrilla (Hydrilla verticillata (L.f.) Royle). The efficacy of integrating this biological control agent with herbicides to improve long-term management of hydrilla was also investigated.

Download or read book Biological Control Agents of Hydrilla Verticillata written by Richard H. Markham and published by . This book was released on 1986 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since its introduction into Florida in the early 1960s, the submerged aquatic plant Hydrilla verticillata has become a serious weed problem in the waterways of the southern United States. Since East Africa forms part of the natural distribution of hydrilla, a search for potential biological control agents in the region was carried out by the Commonwealth Institute of Biological Control from 1981 to 1984. Hydrilla was found to have a wide but disjunct distribution in Uganda (Lake Kioga), Rwanda (Lake Bulera and Mukungwa River), and Burundi (Lake Tanganykia). In Kenya, despite an intensive search, only a single population, probably of exotic origin, was found. The range of the plant appears to have been reduced (especially in Lake Victoria), probably by man-made changes in the environment. In East Africa hydrilla appears to be nonaggressive, and plants in most habitats are small in stature, forming mats on the hydrosoil and rarely reaching the surface. Plant growth appears in general to be constrained by fish grazing, but in Lake Tanganyika hydrilla is seasonally attacked by larvae of a chironomid which destroys many of the apical meristems and curtails upward growth of the plant. This species was not successfully reared, but should be further studied for possible introduction into the United States as it is damaging to hydrilla and may be specific for hydrilla. Pyralid larvae were found on hydrilla at one site but these were not damaging, and the plant was not a preferred host in that region.

Download or read book Aquatic Plant Control Research Program Growth and Rooting Depth Characteristics of Hydrilla Verticillata L f Royle and Myriophyllum Spicatum L on Fertilized and Unfertilized Sediments written by and published by . This book was released on 1994 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: In a series of controlled greenhouse experiments, growth and rooting depth characteristics of Hydrilla verticillata (L.f.) Royle and Myriophyllum spicatum L. were examined relative to sediment-N availability, over a range of sediment depths from 10 to 60 cm. Each species was grown separately on fine- textured, inorganic sediment, either amended with ammonium chloride (N-amended) or rendered N-poor due to previous support of submersed macrophyte growth (nonamended). For both species, diminished biomass production was accompanied by increased root-to-shoot ratios and increased rooting depth (to 60 cm) on nonamended sediment. High production levels in Myriophyllum and Hydrilla on N- amended sediment were unaffected by sediment depth, indicating (along with high tissue N concentrations) that the availability of N under those conditions was nonlimiting. With increased depth of nonamended sediment, both Hydrilla and Myriophyllum increased production and mitigated N-deficiency in plant tissues by increasing root accession of this nutrient from greater sediment depths. This ability, speculated here to be more or less developed in other macrophyte species, may affect the outcome of interspecific interactions, particularly when N concentrations in sediment are low. Aquatic plants, Nitrogen, Sediment composition, Hydrilla, Nutrient limitation, Sediment nutrient availability, Myriophyllum, Nutrient uptake, Submersed macrophytes.

Download or read book Mass Rearing Hydrellia Pakistanae Deonier a Biological Control Agent of Hydrilla Verticillata L f Royle for Release and Establishment written by and published by . This book was released on 2001 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two insect biocontrol agents of Hydrilla verticillata, Hydrellia pakistanae Deonier, from southern India, Pakistan, and northern China, and H. balciunasi Bock, from Australia, have been reared at the U.S. Army Engineer Research and Development Center, Waterways Experiment Station (WES), Aquatic and Wetlands Research and Development Support Facility, Vicksburg, MS, since 1990. Currently, H. pakistanae is still in production; however, the H. balciunasi colony was disbanded in 1994. One main concern with greenhouse/laboratory-rearing procedures used at WES was whether they impacted insect quality. Various quality parameters measured included sex ratio, weight, female egg-laying, and developmental time. Quality data collected from 1990 to 1992 remained fairly uniform, indicating that the quality parameters did not seem to be affected by the rearing procedures. Production costs, however, became a major issue. Based on labor and materials, the cost of producing a single Hydrellia spp. was estimated to be $0.50 per insect. Large numbers of insects are needed for successful field establishment, and current fly production prices made it prohibitive for wide-scale production. Future plans for alternate rearing techniques include construction of a series of outdoor ponds. These ponds would allow for the creation of a large number of high-quality insects and decrease production costs associated with rearing Hydrellia spp.

Download or read book Cryptic Speciation Genetic Diversity and Herbicide Resistance in the Invasive Aquatic Plant Hydrilla Verticillata L f Royle Hydrocharitaceae written by Lori Kim Benoit and published by . This book was released on 2011 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Genetic Relationships Among Invasive Hydrilla Hydrilla Verticillata L f Royle Biotypes in the US and Their Implications for Management written by Nathan E. Harms and published by . This book was released on 2014 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Developing Methodologies to Assess the Influence of Nutritional and Physical Characteristics of Hydrilla Verticillata on Its Biological Control Agents written by and published by . This book was released on 2002 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This technical note describes experimentation used to develop methods of culturing Hydrilla verticillata (L. f.) Royle (hydrilla) to obtain plants with consistent but wide-ranging nutritional and physical characteristics. Results of this research will allow laboratory testing of the impacts of the structural and nutritional quality of hydrilla on insect and fungal pathogen biological control agents.