Transformation and Expression of Two Insect-Resistant Genes to Hybrid Triploid of Chinese White Poplar Resistance to Insect of Transgenic Populus tomentosa Clone-85 plants with Two Insect-resistant Genes SELECTION AND INSECT RESISTANCE OF TRANSGENIC HYBRID POPLAR 741 CARRYING TWO INSECT-RESISTANT GENES The survival and escape of Agrobacterium tumefaciens in triploid hybird lines of Chinese white poplar transformed with two insect-resistant genes Researches on the insect-resistant effect of transgenic hybrid poplar 741 with two insect-resistant genes Exogenous Gene Expression on Transgenic Populus×euramericana cv. ‘74/76‘ Carrying Bivalent Insect-Resistant Genes An effective Transformation System of Sophora japonica Analysis of Main Characteristic of White Poplar Hybrid 741 Transformed Two Insect-Resistant Genes