Response of drought and nutrient stressed loblolly pine grown in native soil and overburden material from the Post Oak Savannah of Texas /
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| Other Authors: | , , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1986.
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| Online Access: | Link to OAKTrust copy |
| Abstract: | Four sources (GR1-1, GR1-2, GR1-6, and S2PT10) of loblolly pine (Pinus taeda L.) were used to evaluate the growth and internal water relations of seedlings in two separate experiments. In the first study, seedlings were grown in mixed overburden and native soil material. Mixed overburden material proved to be the better growth media. Pressure-Volume curves generated from pressure chamber measurements revealed no differences between the internal water relations of seedlings of the four sources grown in either media. The second study utilized the same four pine sources and mixed overburden material. After four months of growth, treatments of water stress (watered every five days and fertilized once a week), nutrient stress (watered on alternate days and not fertilized), water and nutrient stress (watered every five days and not fertilized), and no stress (watered on alternate days and fertilized once a week) were imposed for 80 days. Above ground growth was found to be sensitive to nutrient stress, and below ground growth was sensitive to moisture stress. GR1-6 and GR1-1 exhibited superior growth over S2PT10 and GR1-2. S2PT10 exhibited excellent above ground growth, but poor below ground growth. GR1-2 was the poorest overall performer for growth parameters measured. Water relation data revealed some adaptation in the drought hardy sources, GR1-1, GR1-2, and GR1-6, to water stress conditions through lowered osmotic potential at full turgor, symplastic volume, and elasticity values. The nutrient stress treatments may have resulted in the loss of membrane integrity as symplastic volume values in these treatments increased as the study progressed, indicating the collection of apoplastic water. Needle area per tree was determined and transpirational water loss was gravimetrically estimated. S2PT10 and GR1-1 had significantly more area per tree than GR1-2. The no stress treatment resulted in the largest needle area per tree. The nutrient stress and combined stress treatments resulted in the least surface area per tree. GR1-6 lost more transpirational water in response to treatments of no water stress as compared to the other sources. All sources responded similarly to the water stress treatments with reduced rates of transpiration. The nutrient stress treatment exhibited the greatest transpirational water loss. |
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| Item Description: | Typescript (photocopy). Vita. "Major subject: Forestry." |
| Physical Description: | xviii, 180 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references (leaves 141-146). |