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The Strawberry
Published in N. A. Michael Eskin, Quality and Preservation of Fruits, 1991
Justin R. Morris, W. A. Sistrunk
Cultivars in use today are rigorously screened for plant and fruit characteristics before they are released from breeding programs. The most important plant characteristic is disease resistance, while vigor, growth habit, and runner development are also important. In terms of disease resistance there are several important diseases that are included in most screenings. Among these are numerous virus diseases, leaf blight (Dendrophoma obscurans), leaf scorch (Marssonina potentillae), leaf spot (Ramularia tulasnei), anthracnose (Collectotrichum fragariae), powdery mildew (Oidium fragariae), red stele (Phytophthora fragariae), and verticillium wilt Verticillian dehliae).
Plant Pathogens (Fungi): Biological Control
Published in Brian D. Fath, Sven E. Jørgensen, Megan Cole, Managing Biological and Ecological Systems, 2020
In conclusion, the full potential of controlling plant diseases with fungi still has not been realized. Only a small number of products are on the market, but this is a vast improvement compared to only five years ago. There are still many economic constraints in terms of the cost of development and registration of products and the low cost production of organisms in liquid fermentation or solid on substrates.[5,9] Like chemicals, the risks of fungal BCAs need to be addressed, including the displacement of nontarget microbes, allergenicity to humans and other animals, and toxigenicity and pathogenicity to nontarget organisms.[10] However, there are no existing chemical controls for many diseases, because of deregistration of pesticides, pathogen resistance to pesticides, and environmental concerns. These diseases may be the niches for fungal biocontrol agents. It is unlikely that biological control will succeed alone, but it needs to be integrated with other disease management strategies, including cultural control and genetic disease resistance.
Chlorinated Hydrocarbons
Published in Michael J. Kennish, Ecology of Estuaries: Anthropogenic Effects, 2019
Aquatic environmental surveys have focused on the uptake of PCBs by finfish and shellfish suitable for human consumption. Fish exposed to PCBs experience a higher incidence of fin erosion, epidermal lesions, blood anemia, and altered immune response. Studies have indicated a lower disease resistance in fish exposed to PCBs.62 The U.S. Food and Drug Administration (FDA) effectively controls public exposure to orally ingested PCBs, originally setting their upper limit in the edible portions of fish and shellfish at 5.0 ppm, and later lowering the tolerance level of PCBs to 2.0 ppm in August 1984, as a result of new toxicity data and declining incidences.
Closed-loop organic waste management systems for family farmers in Brazil
Published in Environmental Technology, 2022
René van der Velden, Warde da Fonseca-Zang, Joachim Zang, Dominic Clyde-Smith, Wilson M. Leandro, Priti Parikh, Aiduan Borrion, Luiza C. Campos
Biochar is known to be a good soil enhancer and is especially useful on infertile soil or in water restricted regions [17,38]. Applying biochar to the soil is an effective way to sequester carbon [51], making it a carbon-negative waste management option [17]. It also decreases nitrous oxide and ammonia emissions from fertiliser [48]. For farmers, it is useful because applying biochar improves cation exchange capacity (CEC) of the soil which increases nutrient retention [18], prevents soil acidification, and improves moisture retention [17]. Biochar also improves microbiological soil fertility [51] and disease resistance of plants [50]. These capabilities make the soil more resilient against climate variability [19] and reduce nutrient leaching and fertiliser requirement [18]. Overall, these effects accumulate to improve seed emergence, crop growth and productivity [48]. The technology for creating biochar is well-known, low cost and can be done with locally available materials [18].
Demographic responses of Cladocerans (Cladocera) in relation to different concentrations of humic substances
Published in Journal of Environmental Science and Health, Part A, 2019
Jose Luis Gama Flores, Maria Elena Huidobro Salas, S. S. S. Sarma, S. Nandini
Humification is a natural process playing a fundamental role in nutrient supply to primary producers.[1] During this process different products collectively called humic substances (HS) are liberated mainly into the water and soil.[2] Because humic substances have different functional groups, they often act as chemical stressors leading directly or indirectly to ecological problems.[1] Compared to non-humic substances such as carbohydrates and proteins which are easily degraded, humic substances are much more stable.[3] Humic substances are composed of humin (insoluble fraction), humic acid (soluble in alkaline solution), and fulvic acid (soluble in both acid and base solutions).[4] Fulvic acid, one of the components of humic substances in nature,[3] has been widely used in the agriculture sector as biostimulants.[5] Fulvic acid is also used to enhance the immunity of animals in the veterinary sector. However, in aquacultural operations, the use of humic substances has been low.[6] There is some indication that dietary intake of fulvic acid helps to enhance disease resistance in carps.[7]
Impact of zinc oxide nanoparticles in aqueous environments: influence of concentrations, natural organic matter and ionic strength
Published in Inorganic and Nano-Metal Chemistry, 2020
Deogratius T. Maiga, Hlengilizwe Nyoni, Thabo T. Nkambule, Bhekie B. Mamba, Titus Alfred Makudali Msagati
Zinc oxide nanoparticles, like titanium dioxide (TiO2) and silver (Ag) NPs, are widely used as engineered inorganic nanopesticides.[1,2] Nanopesticides have been found attractive for use as engineered nanoparticles (ENPs) due to the fact that they potentially improve plant disease resistance, stress resistance, utilization of nutrient and hence promote plant growth and increase quality and quantity of produce in agriculture. Therefore, nanopesticides are viewed as products of great significance in agriculture and food production chain.[3] The increase in the application of ZnO nanoparticles has led to a variety of potential ecotoxicological risks emanating from the discharge of ENPs to aquatic environments.[4,5] Previous research studies have revealed interesting findings on the fate and transport of ENPs that are discharged into the natural environment from commercial, agricultural and industrial products.[4,6–9] Some researchers have investigated their environmental fate, behavior, transport and ecotoxicity in the aquatic environment as a function of intrinsic properties of ENPs such as particles stability, particle concentrations (NPC), surface charge, size and shape.[5,9–11] Other researchers have reported that extrinsic factors such as ionic strength (IS), pH and natural organic material (NOM) tend to affect the mobility and fate of ENPs in aquatic system.[5,9,12–14]