الفهرس 
Controlling salt stressOnly 14 pages are availabe for public view
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Abstract
This investigation was conducted to confirm the effect of paclobutrazol (PBZ) the gibberellin biosynthesis inhibitor and its physiological mechanism on salt stress, based on our preliminary observations on grapes and guava. The soil experiment was conducted during two successive seasons : 1994 and 19951and the hydroponic experiment was during spring 1995 and winter 1996 at the department of t greenhouse on the University of Georgia Campus (Athens, GA, USA). A.., Soil experiment : One-year old rooted cuttings of ’Manzanillo’ lorticulture live and ’Nemaguard’ peach were transplanted to 20cm pots in 1994 and 30cm pots in 1995 filled with field soil (from the horticultural farm of the University of Georgia), sand, and pine bark with a ratio of 3:3:4 respectively. During the first week of March 1994 and 1995, and irrigated and fertilized until late May for peach. Olives were transplanted on April 15, and irrigated and fertilized until July 1, 1994, but in 1995 experiment was run simultaneously with peach. Plants were arranged in a randomized complete block design and at the end of the day salt solutions and paclobutrazol sprays (200 mglliter in 1994 and 1995 for peach and 1994 for olive, but the concentration was increased for olive only to 300 mglliter in 1995) were applied to appropriate plants and repeated every month. Salt solutions were derived from six stock solutions CaCI, (2M), NaCl (4M), KC1 (IM), MgSO, (IM), K2S04 (IM), and Na,SO, (1 M), to yield a balance of cations and anions with sodium adsorption ratio (SAR) of either 6 or 1 2, but SAR 12 only in 1995 1 CI-: 1 SO:- as milliequivalent. Salt solutions were concentrations of 0 , 500, 1000, and 2000 mglliter for peach in 1994 and 0, 1000, and 2000 mglliter in 1995, and 0, 2000, 4000, and 6000 mglliter for 1 39, olive in 1994 and 0, 4000, and 8000 mglliter in 1995. Plants were irrigated with one liter of salt solution as needed and leached with tap water after every fourth irrigation to prevent salt accumulation. The electrical conductivity (EC) in the drainage water; was reached about 6 dS1m for peach and about 12 dS/m for olive for the highest concentrations. During the growing season, leaf expansion was measured every other day, area per leaf was obtained from the final leaf expansion readings, relative water content, photosynthesis, stomata1 conductance and intercellular CO, was measured. While, leaf area, dry weight, nutrient elements, CI and Na content and partitioning, and non-structural carbohydrates were measured following plant harvest.