This paper aims to confirm the optimal pruning intensity to promote paulownia growth. Annualdynamic of 8 growth indicators for pruning of three-year-old Paulownia to promote trunk extension weresimulated under 7 treat...This paper aims to confirm the optimal pruning intensity to promote paulownia growth. Annualdynamic of 8 growth indicators for pruning of three-year-old Paulownia to promote trunk extension weresimulated under 7 treatments. The results showed that annual growth process could be modeled reliably byRichards function. Eight growth parameters were developed including fast-growing point (t0), initialpoint of fast-growing period (t1), final point of fast-growing period (t2), fast-growing period (t), growthperiod (Dg), maximum day increment (AGRmax), maximum annual increment (A). Effects of pruning topromote trunk extension on growth parameters were analyzed. Paulownia remaining 3~6 lower branchesafter pruning had relatively longer fast-growing period (t), growth period (Dg), higher average day increment(Am), maximum day increment (AGRmax) and maximum annual increment (A). Therefore, lower diametergrowth of original trunk did not decrease significantly, and upper diameter growth increased to someextent. Height and diameter growth of grafting trunk, and form ratio of grafting trunk were relatively higher.Total stock volume increment was improved significantly under the condition that stock volume incrementof original trunk did not decrease.展开更多
Inorder to carry out trunk extension by lateral buds ,the laws of trunk extension and branching sprouted from lateral buds were investigated in 1-year-old seedlings of P.tomentosaxP,fortunei 33 under natural condition...Inorder to carry out trunk extension by lateral buds ,the laws of trunk extension and branching sprouted from lateral buds were investigated in 1-year-old seedlings of P.tomentosaxP,fortunei 33 under natural conditions.The results indicated：（1）Under conditions of high density and extensive management,42%of individuals in P.tomentosaxP.fortunei 33 showed pseudo dichotomous branching characteristics and could not extend their trunks in the second year.But other individuals showed the characteristics of sympodial branching and pseudo monopodial branching （not from terminal buds ）and could realize natural trunk extension.All the 3types of branching could be called branching of pseudo asis;（2）The stem form quotieties of extended trunk in all individuals wrer larger in the second year ,but only 14%of them could straight extend their trunks and 86%of them needed2-3years to reach straight trunk estension;（3）Among individuals which could extend their trunks ,from upper lateral buds to lower lateral buds on trunks ,the lengths and diameters of branches sprouted from lateral buds became smaller and smaller ,but the angles of branching up to trunk became larger and larger ,and the fourth pair of lateral branches reached to the largest,Under the fourth pair ,the angles of branches became smaller again and those branches all died.展开更多
文摘This paper aims to confirm the optimal pruning intensity to promote paulownia growth. Annualdynamic of 8 growth indicators for pruning of three-year-old Paulownia to promote trunk extension weresimulated under 7 treatments. The results showed that annual growth process could be modeled reliably byRichards function. Eight growth parameters were developed including fast-growing point (t0), initialpoint of fast-growing period (t1), final point of fast-growing period (t2), fast-growing period (t), growthperiod (Dg), maximum day increment (AGRmax), maximum annual increment (A). Effects of pruning topromote trunk extension on growth parameters were analyzed. Paulownia remaining 3~6 lower branchesafter pruning had relatively longer fast-growing period (t), growth period (Dg), higher average day increment(Am), maximum day increment (AGRmax) and maximum annual increment (A). Therefore, lower diametergrowth of original trunk did not decrease significantly, and upper diameter growth increased to someextent. Height and diameter growth of grafting trunk, and form ratio of grafting trunk were relatively higher.Total stock volume increment was improved significantly under the condition that stock volume incrementof original trunk did not decrease.
基金Foundation of Research Startup for Returned Student From Abroad Science Foundation of Henan Province forDistinguished Young Scholars(No.002).
文摘Inorder to carry out trunk extension by lateral buds ,the laws of trunk extension and branching sprouted from lateral buds were investigated in 1-year-old seedlings of P.tomentosaxP,fortunei 33 under natural conditions.The results indicated：（1）Under conditions of high density and extensive management,42%of individuals in P.tomentosaxP.fortunei 33 showed pseudo dichotomous branching characteristics and could not extend their trunks in the second year.But other individuals showed the characteristics of sympodial branching and pseudo monopodial branching （not from terminal buds ）and could realize natural trunk extension.All the 3types of branching could be called branching of pseudo asis;（2）The stem form quotieties of extended trunk in all individuals wrer larger in the second year ,but only 14%of them could straight extend their trunks and 86%of them needed2-3years to reach straight trunk estension;（3）Among individuals which could extend their trunks ,from upper lateral buds to lower lateral buds on trunks ,the lengths and diameters of branches sprouted from lateral buds became smaller and smaller ,but the angles of branching up to trunk became larger and larger ,and the fourth pair of lateral branches reached to the largest,Under the fourth pair ,the angles of branches became smaller again and those branches all died.
