Study On The Effects Of Exogenous IAA And GA₃ On The Formation Of Compression Wood Of Pinus Massoniana Lamb.

Masson pine is the main timber species in south-central of china with high economic value,the wood is widely used in papermaking,construction,furniture and other industries.Masson pine made a great contribution for the country's forestry industry and industrial.Masson pine trees as a fast-growing economy is affected by the prevailing winds,slope,rain,snow and the external environment in the growth process can easily form a compression wood.Compression wood is generally considered to be a defect of wood,pine compression wood has seriously hampered the efficient use of Masson pine timber and related industries,the study mechanism of formation of compression wood softwood trees cultivation and processing of It has important significance.In this paper,the growth of the field and greenhouse cultivation Masson pine branches are used as research object.The inclined Masson pine branches were applyed different concentrations of gibberellin?GA₃?and auxin?IAA?.The effect of exogenous IAA and GA₃ on the formation of the stress wood of Pinus was analyzed and compared.the results are as follows:?1?The effects of different concentrations of IAA and GA₃ on the growth of pinus: the growth of tilt Masson pine were promoted by exogenous hormones IAA?0.01 mg·g-1?,GA₃?10 mg·g-1?,IAA + GA₃?0.01 mg·g-1 + 10 mg·g-1?but were inhibed by IAA?10mg·g-1??2?The effects of different concentrations of IAA and GA₃ on the the tilt of Masson pine shoot's xylem and phloem of different growth.The growth of xylem and phloem of promoted Masson tilt shoot were significantly promoted by treatment with IAA?0.1mg·g-1?,IAA?1mg·g-1?,GA₃?10mg·g-1?,IAA+GA₃?0.01mg·g-1+10mg·g-1?.the growth of xylem growth were inhibited by treatment with IAA?10 mg·g-1?but Compared with other treatment groups,the effect of phloem growth was not obvious.the growth of xylem growth was not significant effect treatment with IAA?0.01mg·g-1??3?The effects of different concentrations of IAA and GA₃ on the the tilt of Masson pine tracheid length.The effect of IAA?0.01 mg·g-1?on the cell growth of Pinus was not obvious.The number of the tracheid and tracheid length were promoted on the upside of Inclined branch but the number of the tracheid and cell wall thickness underside of the Inclined branch were inhibited by applying IAA?0.01 mg·g-1?,GA₃?10 mg·g-1?,IAA + GA₃?0.01 mg·g-1 + 10 mg·g-1??4?The effects of different concentrations of IAA on the microfibril angle of compression wood for tilt Masson pine,IAA?0.1 mg·g-1?,IAA?1 mg·g-1?,IAA?10 mg·g-1?of Pinus massoniana tilt on the underside of the branches secondary cell wall micro fibril angle size of the tube,with the increase of concentration of IAA applied,Masson Pine pressure tracheid microfibril angle decreases gradually.?5?Masson Pine decline branches on the side of applying different concentration of IAA?0.1 mg·g-1?,IAA?1 mg·g-1?,IAA?10 mg·g-1?of Pinus massoniana wood pressure pigment content,with the increase of IAA concentration should be the relative content of compression wood lignin decreased gradually.