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Information storage technologies are changing, so this project is focused on the future and the use of new videodisc technology. A model plant science inquiry-learning tool was developed for vocational agriculture students using advanced video and computer technology. The interactive videodisc lesson, which focuses on plant identification, was designed to increase learning and allow teachers to spend more time with students.

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Gibberellic Acid (GA3) was applied to `Venus' table grape flower clusters seven days after full bloom at 0, 150 and 300 ppm in 1987 and 1988. For both years, berry, cluster and average individual seed trace weights were not significantly affected by GA3 treatment. Total seed traces/berry were reduced an average of 50%, resulting in one seed trace/berry for GA3 treated clusters compared to two seed traces/berry for the control. Yield was increased in 1988 with the 300 ppm rate.

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Gas exchange (assimilation, transpiration, water use efficiency, and conductance) of `Shawnee' blackberry were measured under field conditions with a portable system (ADC-IRGA with Parkinson Leaf Chamber). Gas exchange primocane pentifoliate leaflets were similar. Gas exchange rates of leaves along a cane exhibited a quadratic function of leaf position with leaves in lower-mid sections (relative position 0.3 - 0.5) having higher A, TR, WUE, gs than either basal or apical leaves. Leaves subtending fruiting laterals on fruiticanes had higher assimilation than similar age leaves on primocanes but did not differ in Tr, WUE, or gs. Primocanes had estimated dark respiration rates of 0.33mg·dm-1.hr-1, estimated light compensation at 14-20 mol.m-2.s-1, estimated light saturation at 1000-1100 mol.m-2.s-1 with maximum A rates ranging from 24-30 mg CO2.dm-1.hr-1. Measurements were made at field temperatures ranging from 24-35 C. Although temperature response was not measured, correlation indicated that Tr, WUE, and gs were more closely related to temperature than A. Similarly, Tr and WUE were more closely related to gs than A (r = 0.6 to 0.8).

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An investigation was conducted over 2 years to evaluate the effect of N rate and time of application on fruit composition of `Arapaho' thornless erect blackberry (Rubus L., subgenus Eubatus). N from ammonium nitrate was applied at 56 or 112 kg·ha-1 in single applications, or at 112 kg·ha-1 as a split application with 0 kg·ha-1 as the control. Increasing N rates increased fruit N and pH but did not affect soluble solids concentration, titratable acidity, sugar-acid ratio, and total solids. Timing of N application had no effect on the fruit characteristics measured.

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