Partially modified Bt Cry1Ac gene and the arrowhead proteinase inhibitor (API) gene were used to construct a plant transformation vector pBtiA and this construct was transferred into the genome of the hybrid popla...Partially modified Bt Cry1Ac gene and the arrowhead proteinase inhibitor (API) gene were used to construct a plant transformation vector pBtiA and this construct was transferred into the genome of the hybrid poplar 741 [ Populus alba L.×( P. davidiana Dode+ P. simonii Carr.)× P. tomentosa Carr.] by Agrobacterium _ mediated transformation. Ten kanamycin resistant plants have been regenerated. Upon insect bioassay using Clostera anachoreta (Fabricius), three of the examined plants were demonstrated to be highly resistant to the testing insects. The mortality of insect larvae on one plant was higher than 90% in 6 days after infestation and the growth of the survival larvae were seriously inhibited. Results of PCR and Southern blot analysis indicated that both Bt Cry1Ac gene and API gene were integrated as a single copy into the genomes of these three plants when Cry1Ac gene fragment was used as the probe. Protein dot blot immunoassay and ELISA analysis revealed that at least the Cry1Ac protein was produced in these three transgenic plants and the expression levels were estimated to be approximately 0.015% of the leaf total soluble protein. This is the first report on insect resistant transgenic hybrid poplar 741 that expresses two insecticidal protein genes.展开更多
As a basic measure for forest management,pruning has an important impact on the tree trunk shape,wood qulity,etc. At present,in the process of growing fast-growing and high-yielding plantation,afforestation was took i...As a basic measure for forest management,pruning has an important impact on the tree trunk shape,wood qulity,etc. At present,in the process of growing fast-growing and high-yielding plantation,afforestation was took into account,whereas management after planting was ignored,which had much detrimental effect on woodland’s quality and productivity. The paper studied the topic to find a scientific pruning model that could provide a guideline for the management in forest production. The plantation and the intercropping of poplar-crop were pruned in four different levels in Hebei and Shandong province. The levels were respectively light p1 (1/6 crown was pruned),medium p2 (2/6 crown was pruned),strong p3 (3/6 crown was pruned),heavy p4 (4/6 crown was pruned) and the control (unpruned). Heights and diameters at breast height(DBH) were measured. Diameter growth and cutting-area increment in one year from ten parsed trees were counted. The volume growth of trunk (below 9 m) was calculated. The results were:1) the difference of relative growth rate for different pruning treatment was not significant (P<0.05),which demonstrated the nutrition for height growth came from the branches and leaves of the top crown; 2) The difference of relative growth rate of DBH was significant(P<0.01). That is,the greater of pruning intensity,the smaller relative growth in the DBH. 3) The stem growth of parsed disk at different height was fluctuant among the different treatments. From stem base (0.0 m) to 9 m height of the trunk,the stem increase of the lower half reduced along with the increase of pruning intensity,while the growth of the upper half in pruning trees was bigger than that of non-pruning ones. 4) The difference of volume growth rate for different treatments was significant,all of the pruning treatments were bigger than the control. The medium p2 had the biggest growth,and the order was CK<p4<p1<p3<p2,which suggested that reasonable pruning can improve the growth of volume. However an excessive pruning reduced volume growth. 5展开更多
基金ThePresidentialFoundationofTheChineseAcademyofSciences NaturalScienceFoundationofHebeiProvince China
文摘Partially modified Bt Cry1Ac gene and the arrowhead proteinase inhibitor (API) gene were used to construct a plant transformation vector pBtiA and this construct was transferred into the genome of the hybrid poplar 741 [ Populus alba L.×( P. davidiana Dode+ P. simonii Carr.)× P. tomentosa Carr.] by Agrobacterium _ mediated transformation. Ten kanamycin resistant plants have been regenerated. Upon insect bioassay using Clostera anachoreta (Fabricius), three of the examined plants were demonstrated to be highly resistant to the testing insects. The mortality of insect larvae on one plant was higher than 90% in 6 days after infestation and the growth of the survival larvae were seriously inhibited. Results of PCR and Southern blot analysis indicated that both Bt Cry1Ac gene and API gene were integrated as a single copy into the genomes of these three plants when Cry1Ac gene fragment was used as the probe. Protein dot blot immunoassay and ELISA analysis revealed that at least the Cry1Ac protein was produced in these three transgenic plants and the expression levels were estimated to be approximately 0.015% of the leaf total soluble protein. This is the first report on insect resistant transgenic hybrid poplar 741 that expresses two insecticidal protein genes.
文摘As a basic measure for forest management,pruning has an important impact on the tree trunk shape,wood qulity,etc. At present,in the process of growing fast-growing and high-yielding plantation,afforestation was took into account,whereas management after planting was ignored,which had much detrimental effect on woodland’s quality and productivity. The paper studied the topic to find a scientific pruning model that could provide a guideline for the management in forest production. The plantation and the intercropping of poplar-crop were pruned in four different levels in Hebei and Shandong province. The levels were respectively light p1 (1/6 crown was pruned),medium p2 (2/6 crown was pruned),strong p3 (3/6 crown was pruned),heavy p4 (4/6 crown was pruned) and the control (unpruned). Heights and diameters at breast height(DBH) were measured. Diameter growth and cutting-area increment in one year from ten parsed trees were counted. The volume growth of trunk (below 9 m) was calculated. The results were:1) the difference of relative growth rate for different pruning treatment was not significant (P<0.05),which demonstrated the nutrition for height growth came from the branches and leaves of the top crown; 2) The difference of relative growth rate of DBH was significant(P<0.01). That is,the greater of pruning intensity,the smaller relative growth in the DBH. 3) The stem growth of parsed disk at different height was fluctuant among the different treatments. From stem base (0.0 m) to 9 m height of the trunk,the stem increase of the lower half reduced along with the increase of pruning intensity,while the growth of the upper half in pruning trees was bigger than that of non-pruning ones. 4) The difference of volume growth rate for different treatments was significant,all of the pruning treatments were bigger than the control. The medium p2 had the biggest growth,and the order was CK<p4<p1<p3<p2,which suggested that reasonable pruning can improve the growth of volume. However an excessive pruning reduced volume growth. 5