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One of the motivating reasons for the development of hydroponics was avoidance of root pathogens. Hydroponics involves growing crops in relatively sterile media, isolated from the underlying soil which may have disease pressure. However, even when hydroponics is coupled with controlled environments such as high tunnels and climate-controlled greenhouses, soil-borne pathogens can enter the growing area and proliferate due to optimal environmental conditions for pathogen growth. Control of root pathogens is difficult and usually achieved through synthetic fungicides since few biocontrol options are available. Compost water extracts (CWE) have recently been gaining the attention of greenhouse growers because they may be a low-cost, environmentally friendly approach to control root disease. CWE are mixtures of compost and water incubated for a defined period of time, either with or without aeration, and with or without additives intended to increase microbial populations, which in turn suppress disease. Much anecdotal, but very little scientific, evidence exists describing CWE effect on suppressing soil-borne pathogens. The present study 1) examined the effect of an aerated CWE on disease suppression at the laboratory scale and in container studies using different soilless substrates, 2) investigated a phenotypic change at the root level caused by CWE that may be associated with disease suppression, and 3) isolated some factors in the production of CWE that affect the ability of a CWE to suppress disease. The common model pathogen-host system of Fusarium solani f.sp. pisi and pea was used to examine CWE-induced disease suppression, with information then being translatable to similar patho-systems involved in greenhouse crop production. In the first study, laboratory-based root growth and infection assays resulted in 100% suppression of F. solani when roots were drenched in CWE. These protected seedlings were then taken to a greenhouse and transplanted into fine coconut

Recent national and local science education reform efforts to promote scientific and hydrologic literacy call for a new vision of science teaching. This is a vision where the understanding of science concepts is emphasized over the memorization of facts, and where students are engaged in "inquiry-based" laboratory experiences rather than the typical "cookbook" laboratory experiences. In order to align with this vision, reformbased instructional practices need to be employed. Two such practices used in the general education hydrology courses at the University of Arizona are described in the two manuscripts that make up the bulk of this study. The first manuscript concerns Vee maps, which support inquiry and conceptual understanding. The second manuscript discusses the use of Teaching Teams to support inquiry activities in the classroom by enlisting peer assistants to help the groups during Vee map, or other inquiry-based, investigations. Taken as a whole, these manuscripts focus on two reform-based instructional methods that can be used to promote student learning in general education hydrology.