Transgene stability of transgenic hybrid of Populus〔(Populus tomentosa ×P. bolleanaP. tomentosa〕 and its effect on soil microorganisms STUDIES ON PHOOTOSYNTHETIC PROPERTIES OF POPULUS DELTOIDES cv. QTL Analysis of Leaf Morphology and Spring Bud Flush in (Populus tomentosa×P. bolleanaP. tomentosa