How can we regulate an invasive alien species of high commercial value?Black locust(Robinia pseudoacacia L.)has a unique capacity for seed dispersal and high germination.Field surveys indicate that black locust increa...How can we regulate an invasive alien species of high commercial value?Black locust(Robinia pseudoacacia L.)has a unique capacity for seed dispersal and high germination.Field surveys indicate that black locust increases its growing area with sprouting roots and the elongation of horizontal roots at a soil depth of 10 cm.Therefore,a method to regulate the development of horizontal roots could be eff ective in slowing the invasiveness of black locust.In this study,root barrier panels were tested to inhibit the growth of horizontal roots.Since it is labor intensive to observe the growth of roots in the fi eld,it was investigated in a nursery setting.The decrease in secondary fl ush,an increase in yellowed leafl ets,and the height in the seedlings were measured.Installing root barrier panels to a depth of 30 cm eff ectively inhibit the growth of horizontal roots of young black locust.展开更多
Let be an injective function. For a vertex labeling f, the induced edge labeling is defined by, or;then, the edge labels are distinct and are from . Then f is called a root square mean labeling of G. In this paper, we...Let be an injective function. For a vertex labeling f, the induced edge labeling is defined by, or;then, the edge labels are distinct and are from . Then f is called a root square mean labeling of G. In this paper, we prove root square mean labeling of some degree splitting graphs.展开更多
Split-root solution culture was used to study the promoting effect of lanthanum on rice (Oryza sativa) growth and its physiological mechanisms. Results sho w that low concentration (0.05～1.5 mg·L -1) increases...Split-root solution culture was used to study the promoting effect of lanthanum on rice (Oryza sativa) growth and its physiological mechanisms. Results sho w that low concentration (0.05～1.5 mg·L -1) increases rice yield an d grain numbers. High concentration depresses grain formation (9～30 mg·L -1 ) and root elongation (1.5～30 mg·L -1). No significant influence on str aw dry weight was found over the whole concentration range except the 0.05 mg·L -1 treatment. With the increase of La concentration from 0.05 to 0.75 mg· L -1, catalase (CAT) activity in the first fully expandeing leaves and root s decreases. When La concentration is greater than 0.75 mg·L -1 or less than 9 mg·L -1, it significantly decreases superoxide dismutase activity ( SOD) in the leaves and roots. No significant effects were found on chlorophyll, protein and malondialdehyde (MDA) content. Possible mechanisms of La′s promotin g effect on rice growth and reduction effect of ·O- 2 were discussed.展开更多
We investigated the influence of season on the rooting be- haviour of eight important bamboo species viz., Bambusa balcooa, B. bambos, B. nutans, B. tuMa, B. vulgaris, Dendrocalamus giganteus, D. hamiltonii and D. str...We investigated the influence of season on the rooting be- haviour of eight important bamboo species viz., Bambusa balcooa, B. bambos, B. nutans, B. tuMa, B. vulgaris, Dendrocalamus giganteus, D. hamiltonii and D. strictus. We collected 2-3 node culm cuttings in three growing seasons viz. spring （March）, summer （June） and rainy （August） from superior candidate plus clumps （CPCs） centralized in the germplasm garden. Cuttings were placed horizontally in sand and were provided with intermittent misting at regular intervals. Bamboo species exhibited differential rhizogenesis behavior in different seasons. The study reveals significant variation in sprouting and rooting behaviour in different bamboo species. B. bambos had maximum rooting （78.89%）, followed by B. vulgaris （74.44%）. In general, the potential of different bamboo species for rooting was found to be in the order： B. bambos 〉 B. vulgaris 〉 B. balcooa 〉 D. hamiltonii 〉 B. tulda 〉 D. strictus 〉 D. giganteus 〉B. nutans. The maximum rooting was recorded in spring （56.67%）, which was closely followed by summer （54.58%）. In winter season, minimum rooting （36.67%） was observed. The interaction effect of species x season was also significant on sprouting and rooting pa- rameters. In B. balcooa, B. nutans, B. vulgaris, D. hamiltonii and D. strictus, cuttings collected in summer season showed maximum sprouting and rooting, whereas, B. bambos, B. tulda and D. giganteus had maximum rooting in spring. The maximum number of roots developed per cutting was observed in B. tulda （43.8） during spring season.展开更多
基金supported in part by the Research Faculty of Agriculture of Hokkaido University.
文摘How can we regulate an invasive alien species of high commercial value?Black locust(Robinia pseudoacacia L.)has a unique capacity for seed dispersal and high germination.Field surveys indicate that black locust increases its growing area with sprouting roots and the elongation of horizontal roots at a soil depth of 10 cm.Therefore,a method to regulate the development of horizontal roots could be eff ective in slowing the invasiveness of black locust.In this study,root barrier panels were tested to inhibit the growth of horizontal roots.Since it is labor intensive to observe the growth of roots in the fi eld,it was investigated in a nursery setting.The decrease in secondary fl ush,an increase in yellowed leafl ets,and the height in the seedlings were measured.Installing root barrier panels to a depth of 30 cm eff ectively inhibit the growth of horizontal roots of young black locust.
文摘Let be an injective function. For a vertex labeling f, the induced edge labeling is defined by, or;then, the edge labels are distinct and are from . Then f is called a root square mean labeling of G. In this paper, we prove root square mean labeling of some degree splitting graphs.
文摘Split-root solution culture was used to study the promoting effect of lanthanum on rice (Oryza sativa) growth and its physiological mechanisms. Results sho w that low concentration (0.05～1.5 mg·L -1) increases rice yield an d grain numbers. High concentration depresses grain formation (9～30 mg·L -1 ) and root elongation (1.5～30 mg·L -1). No significant influence on str aw dry weight was found over the whole concentration range except the 0.05 mg·L -1 treatment. With the increase of La concentration from 0.05 to 0.75 mg· L -1, catalase (CAT) activity in the first fully expandeing leaves and root s decreases. When La concentration is greater than 0.75 mg·L -1 or less than 9 mg·L -1, it significantly decreases superoxide dismutase activity ( SOD) in the leaves and roots. No significant effects were found on chlorophyll, protein and malondialdehyde (MDA) content. Possible mechanisms of La′s promotin g effect on rice growth and reduction effect of ·O- 2 were discussed.
基金supported by National Mission on Bamboo Applications (NMBA),Department of Science & Technology,New Delhi, India
文摘We investigated the influence of season on the rooting be- haviour of eight important bamboo species viz., Bambusa balcooa, B. bambos, B. nutans, B. tuMa, B. vulgaris, Dendrocalamus giganteus, D. hamiltonii and D. strictus. We collected 2-3 node culm cuttings in three growing seasons viz. spring （March）, summer （June） and rainy （August） from superior candidate plus clumps （CPCs） centralized in the germplasm garden. Cuttings were placed horizontally in sand and were provided with intermittent misting at regular intervals. Bamboo species exhibited differential rhizogenesis behavior in different seasons. The study reveals significant variation in sprouting and rooting behaviour in different bamboo species. B. bambos had maximum rooting （78.89%）, followed by B. vulgaris （74.44%）. In general, the potential of different bamboo species for rooting was found to be in the order： B. bambos 〉 B. vulgaris 〉 B. balcooa 〉 D. hamiltonii 〉 B. tulda 〉 D. strictus 〉 D. giganteus 〉B. nutans. The maximum rooting was recorded in spring （56.67%）, which was closely followed by summer （54.58%）. In winter season, minimum rooting （36.67%） was observed. The interaction effect of species x season was also significant on sprouting and rooting pa- rameters. In B. balcooa, B. nutans, B. vulgaris, D. hamiltonii and D. strictus, cuttings collected in summer season showed maximum sprouting and rooting, whereas, B. bambos, B. tulda and D. giganteus had maximum rooting in spring. The maximum number of roots developed per cutting was observed in B. tulda （43.8） during spring season.
