Arboriculture & Urban Forestry 33(6): November 2007 403 Table 5. Paclobutrazol enhanced recovery of leaf PI, necrosis, and chlorophyll content of containerized English oak (Quercus robur L.) placed outdoors with time (9 weeks) based on quadratic regression analysis after the cessation of 3 weeks of drought.z PI Treatment Control 2 mL (0.06 fl oz) PBZ foliar spray 4 mL (0.12 fl oz) PBZ foliar spray 5 mL (0.15 fl oz) PBZ root drench 10 mL (0.3 fl oz) PBZ root drench Regression: y a+ bT + cT2 y –2.39 + 2.52T – 0.21T2 y –1.58 + 2.55 – 0.19T2 y 1.36 + 0.70T + 0.02T2 y 0.62 + 1.30T – 0.06T2 y 0.17 + 2.66T – 0.28T2 r2 Leaf necrosis Regression: y a+ bT + ct2 0.90 y 4.06 + 0.05T – 0.04T2 0.83 y 1.97 – 0.20T + 0.01T2 0.87 y 2.47 – 0.34T + 0.02T2 0.47 y 2.15 – 0.20T + 0.00T2 0.77 y 2.33 – 0.25T + 0.01T2 r2 Chlorophyll content Regression: y a+ bT + cT2 0.89 y 22.3 + 9.98T – 1.07T2 0.91 y 34.8 + 2.48T + 0.22T2 0.73 y 28.4 + 11.47T – 0.38T2 0.90 y 51.2 – 4.48T + 1.83T2 0.86 y 34.8 + 8.32T – 0.21T2 r2 Electrolyte leakage (%) Regression: y a+ bT + cT2 0.95 y 28.2 – 1.56T – 0.21T2 0.98 y 13.0 –3.32T + 0.25T2 0.93 y 8.94 – 0.04T – 0.13T2 0.77 y 15.3 – 2.07T – 0.00T2 0.81 y 9.48 – 0.28T – 0.19T2 r2 0.92 0.85 0.83 0.96 0.93 zPBZ-treated plants: PI and leaf chlorophyll content, values mean of ten trees, five leaves per tree. Electrolyte leakage values mean of ten trees, two leaves per tree. Leaf necrosis values mean of ten trees. Controls: PI and leaf chlorophyll content, values mean of two trees, five leaves per tree. Pn and electrolyte leakage values mean of two trees, two leaves per tree. Leaf necrosis values mean of two trees. y leaf PI, necrosis, chlorophyll content, and electrolyte leakage value; a leaf PI, necrosis, chlorophyll content, and electrolyte leakage of control value (calculated intercept); b rate of PI, necrosis, chlorophyll content and electrolyte leakage with time (T); c rate of change of leaf PI, necrosis, chlorophyll content, and electrolyte leakage. PBZ paclobutrazol; PI chlorophyll fluorescence. tegrity compared with non-PBZ-treated trees (controls). Overall, recovery (PI, leaf chlorophyll content, necrosis, elec- trolyte leakage) rates of drought-damaged trees treated with PBZ ranged from 20% to 50% higher than non-PBZ-treated trees (Tables 5 and 6). In all cases, control trees (non-PBZ- treated) had the least capacity for recovery. In both English and evergreen oak, no major differences in recovery rates were recorded between PBZ-treated trees irrespective of Table 6. Paclobutrazol enhanced recovery of leaf PI, necrosis, and chlorophyll content of containerized evergreen oak (Quercus ilex L.) placed outdoors with time (9 weeks) based on quadratic regression analysis after the cessation of 3 weeks of drought.z PI Treatment Control 2 mL (0.06 fl oz) PBZ foliar spray 4 mL (0.12 fl oz) PBZ foliar spray 5 mL (0.15 fl oz) PBZ root drench 10 mL (0.3 fl oz) PBZ root drench Regression: y a+ bT + cT2 y 0.88 + 0.309T + 0.07T2 y 0.16 + 1.99T – 0.13T2 y –0.20 + 3.04T – 0.30T2 y 1.33 + 0.807T + 0.02T2 y 1.57 + 1.79T – 0.14T2 r2 Leaf necrosis Regression: y a+ bT + cT2 0.93 y 4.06 – 0.14T – 0.0212 0.94 y 2.62 – 0.01T – 0.01T2 0.90 y 3.29 – 0.50T + 0.04T2 0.97 y 3.01 – 0.10T – 0.01T2 0.95 y 2.54 + 0.20T – 0.00T2 r2 Chlorophyll content Regression: y a+ bT + cT2 0.92 y 46.7 + 3.60T + 0.20T2 0.70 y 88.1 + 5.97T – 0.52T2 0.96 y 55.2 + 6.44T + 0.64T2 0.96 y 61.3 + 7.53T – 0.01T2 0.93 y 82.0 + 0.52T + 0.83T2 r2 Regression: y a+ bT + cT2 0.90 y 31.5 – 5.81T + 0.45T2 0.88 y 20.1 – 1.66T – 0.14T2 0.89 y 20.7 – 2.57T + 0.09T2 0.71 y 16.1 – 0.17T – 0.32T2 0.88 y 10.9 + 1.36T – 0.40T2 Electrolyte leakage (%) r2 0.90 0.95 0.87 0.82 0.99 zTwo milliliters PBZ foliar spray and 5 mL (0.15 fl oz) PBZ root drench-treated plants: PI and leaf chlorophyll content, values mean of eight trees, five leaves per tree. Pn and electrolyte leakage values mean of eight trees, two leaves per tree. Leaf necrosis values mean of eight trees. Four milliliters PBZ foliar spray and 10 mL (0.3 fl oz) PBZ root drench-treated plants: PI and leaf chlorophyll content, values mean of six trees, five leaves per tree. Pn and electrolyte leakage values mean of six trees, two leaves per tree. Leaf necrosis values mean of six trees. Controls: PI and leaf chlorophyll content, values mean of four trees, five leaves per tree. Pn and electrolyte leakage values mean of four trees, two leaves per tree. Leaf necrosis values mean of four trees. y leaf PI, necrosis, chlorophyll content, and electrolyte leakage value; a leaf PI, necrosis, chlorophyll content, and electrolyte leakage of control value (calculated intercept); b rate of PI, necrosis, chlorophyll content, and electrolyte leakage with time (T); c rate of change of leaf PI, necrosis, chlorophyll content, and electrolyte leakage. PBZ paclobutrazol; PI chlorophyll fluorescence; Pn photosynthetic CO2 fixation. ©2007 International Society of Arboriculture
November 2007
| Title Name |
Pages |
Delete |
Url |
| Empty |
Search Text Block
Page #page_num
#doc_title
Hi $receivername|$receiveremail,
$sendername|$senderemail wrote these comments for you:
$message
$sendername|$senderemail would like for you to view the following digital edition.
Please click on the page below to be directed to the digital edition:
$thumbnail$pagenum
$link$pagenum
Your form submission was a success. You will be contacted by Washington Gas with follow-up information regarding your request.
This process might take longer please wait
