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Trichoderma has been known to control soil-borne pathogens and to enhance plant growth and development. The objective of the study was to evaluate dispersal of Trichoderma via irrigation water in container production. 3.81 × 30 cm PVC pipes were filled with Sunshine Mix #5 up to 25 cm. Ten tomato seeds, boiled and coated with T. harzianum, were placed at 0.5 cm depth in each pipe. All treatments were irrigated carefully with 100 ml of DD water from top every 2 days. Before and one hour after irrigation the potting mix was sampled from 5 depths at 5.5 cm intervals every 2 days for 8 days to determine Trichoderma density. Trichoderma density was significantly higher in after irrigation. Trichoderma dispersed up to 25 cm deep in container potting mix after 4 days via irrigation water. This study successfully demonstrates that Trichoderma can be rapidly dispersed via irrigation water.

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Magnetic Resonance Imaging (MRI) is currently considered as a nondestructive and noninvasive method for observing the distribution, concentration, and status of water in biological materials. However, effects of static magnetic fields of MRI systems on plant growth and development remain controversial. This study was conducted to investigate the water imbibition and radicle growth of Pisum sativum (cv. Little Marvel), Zea mays (cv. Pioneer 3379), and Glycine max (cv. Forrest) seeds oriented to four directions and exposed to six different magnetic field strengths commonly used in MRI systems.

Seeds were embedded in a water saturated synthetic foam medium, and were oriented, with respect to their hilum or embryo, to the east, south, west, or north. Seeds were then exposed to either 2, 4, 6, 8, 10, or 15 kilogauss static magnetic fields for 48 hours (water imbibition) or 54 hours (radicle growth).

The orientation of seeds and the magnetic field strengths had no effect on water imbibition or radicle growth of seeds tested. However, long term exposure retarded pea radicle growth in 2 KG treatment, enhanced soybean radicle growth in 10 KG treatment, but had no effect on corn radicle growth.

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A top-and-bottom split root system of Lycopersicon lycopersicum `Burpee's Pixie' was developed using a nonferromagnetic phenolic foam growing medium. The objective of the study was to observe hydrodynamic activity in the roots and substrate when one side of the split root system was dehydrated. After withholding water for 22 days from the top block, the plant and substrate were scanned for 46.5 hours every 30 min using a Siemens 1.5 tesla magnetron whole body imaging system operating at 63 MHz. Resulting images were compiled into a time lapse movie and clearly showed selective root hydration and dehydration on the dry side of the split root system. Those changes in the root MRI signal intensity suggest a cyclic hydration of the roots and a partitioning of water among roots in dry environment.

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Nuclear Magnetic Resonance Imaging is currently being investigated as a nondestructively and noninvasively observing plant-water relationships, Researchers have not considered the effects of magnetic fields on plant growth and development. This study was conducted to investigate the effects of magnetic fields on seed water imbibition and radicle growth. Corn (cv. pioneer 3379), pea (cv. little marvel), and soybean (cvs. forrest and D86-4669) seeds were embedded in petri dishes with water saturated Smither's oasis porus foam, and were oriented for the East, South, West, and North. Seeds were exposed to either 1.5 Tesla or 1×10-10 Tesla static magnetic field for 48 hours. Changes in seed weights and radicle lengths were measured. Results showed that the strong magnetic field and seed orientations had no effect on the water imbibition rate. However, growth of corn and pea radicles was affected by the magnetic field. The 1.5 Tesla magnetic field enhanced the growth of corn radicle length, whereas it retarded the growth of pea radicles.

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Nuclear Magnetic Resonance Imaging is currently being investigated as a nondestructively and noninvasively observing plant-water relationships, Researchers have not considered the effects of magnetic fields on plant growth and development. This study was conducted to investigate the effects of magnetic fields on seed water imbibition and radicle growth. Corn (cv. pioneer 3379), pea (cv. little marvel), and soybean (cvs. forrest and D86-4669) seeds were embedded in petri dishes with water saturated Smither's oasis porus foam, and were oriented for the East, South, West, and North. Seeds were exposed to either 1.5 Tesla or 1×10-10 Tesla static magnetic field for 48 hours. Changes in seed weights and radicle lengths were measured. Results showed that the strong magnetic field and seed orientations had no effect on the water imbibition rate. However, growth of corn and pea radicles was affected by the magnetic field. The 1.5 Tesla magnetic field enhanced the growth of corn radicle length, whereas it retarded the growth of pea radicles.

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Recent trends in greenhouse container production suggest using ebb and flow irrigation for water conservation and pollution control. A major problem in this system is management of soil borne pathogens. Some species of Trichoderma, a beneficial fungi, are known to control Pythium and Phytopthora in container production. This study investigates the potential of applying a Trichoderma conidial spore suspension in an ebb and flow irrigation system. Trichoderma conidia were collected from culture and placed in 101 l stock solution tanks at 10-2 and 10-4 colony forming units (CFU) per ml. Six inch container grown Dendranthema grandiflora `Delano', were irrigated as needed. To determine Trichoderma density in the root environment, soil samples were acquired from the container at 7 day intervals. Results showed that initial population densities of 10-4 CFU/ml were required to achieve adequate container populations to control disease after one irrigation. This study successfully demonstrated that Trichoderma could be dispersed through irrigation water into container plants in an ebb and flow system.

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Experiments were conducted to investigate the feasibility of biological control measures to control Western Flower Thrips. Thrips population and preferred trap color were examined using sticky trap tapes in 5 fluorescent colors, orange, yellow, green, blue and pink. Results indicated that pink is more effective in attracting thrips than the traditional yellow or the newly acclaimed blue sticky traps on the market now. Studies were also conducted to determine if the entomogenous nematode (Steinernema feltiae) could invade and parasitize Western Flower Thrips, and which stage of the thrips life cycle was most susceptible to parasitization. Thrips were dissected and checked for nematode invasion at 24, 48 and 72 hours after inoculation. S. feltiae was found to invade the body cavity after 24 hours in the larval stage of Western Flower Thrips resulting in death.

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Trichoderm a spp. are currently being investigated for biological control of soil-borne pathogens and their potential to enhance plant growth and development. The influence of T. harzianum and T. hamatum on growth of 7 bedding plant species was Investigated. Trichoderm a formulated in peat moss and wheat bran, was mixed into germination and growing media at 1 × 106 cfu per gram of medium. Seeds were germinated in plugs and later grown in cellpacks containing a treated and non-treated medium until market stage. Plants were evaluated by measuring height, fresh and dry weight, and number and timing of flowering. Growth enhancement was found in marigold (14.8% dw), petunia (15.5% dw) and tomato (38.2% dw), however, no significant differences were seen in celosia, impatiens, salvi a and vinca. Results suggest that growth enhancement by Trichoderm a is species dependent and that Trichoderm a applied in the plug mix remains-effective through marketing stage.

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Experiments were conducted to investigate the feasibility of biological control measures to control Western Flower Thrips. Thrips population and preferred trap color were examined using sticky trap tapes in 5 fluorescent colors, orange, yellow, green, blue and pink. Results indicated that pink is more effective in attracting thrips than the traditional yellow or the newly acclaimed blue sticky traps on the market now. Studies were also conducted to determine if the entomogenous nematode (Steinernema feltiae) could invade and parasitize Western Flower Thrips, and which stage of the thrips life cycle was most susceptible to parasitization. Thrips were dissected and checked for nematode invasion at 24, 48 and 72 hours after inoculation. S. feltiae was found to invade the body cavity after 24 hours in the larval stage of Western Flower Thrips resulting in death.

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Control failures of many insecticides used against the western flower thrips (WFT), Frankiniella occidentalis (Pergande), have been reported from several locations by greenhouse operators. To document resistance, thrips were bioassayed by placing them in vials coated with doses of diazinon, methomyl, bendiocarb, dimethoate, azinphosmethyl and cypermethrin at (100, 50, 10, 5, 1, 0.5 and 0.1 g/vial). Adult female WFT were collected from a colony exhibiting control failures using organophosphate, carbamate and pyrethroid insecticides. A colony showing no resistance was used as a control. The LC50's of the resistant and susceptible strains were diazinon 49.3 and 4.6 g/vial, cypermethrin no mortality and 3.7 g/vial, and azinphosmethyl 20.2 and 2.l g/vial respectively. Results show resistance is present as well as cross resistance to diazinon and cypermethrin because the resistant population was never exposed to these compounds.

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