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161.
Mark W. Hester 《Restoration Ecology》2011,19(2):216-224
Planting multiple species in wetland restoration sites could potentially accelerate ecological succession while enhancing ecological services. Our study of thick‐mat floating marsh demonstrated that two species performed better than monocultures for developing a more structurally sound root mat. Although Panicum hemitomon is the typical dominant and focal species of all restoration efforts of this habitat type, we evaluated the effects of additional species, including Sagittaria lancifolia, a ubiquitous floating marsh constituent, and three laterally growing specialists (Alternanthera philoxeroides, Hydrocotyle ranunculoides, and Ludwigia peploides). In a mesocosm experiment, we found greater P. hemitomon biomass in monocultures but greater vegetative cover and total mat biomass with P. hemitomon plus L. peploides, but not greater biomass in the most species‐rich treatment or treatment with the greatest initial planting density. We conclude that L. peploides aids restoration of thick‐mat floating marsh by increasing mat buoyancy, enhancing lateral growth, and providing greater root mat structural integrity. This type of laterally growing specialist should accelerate coalescence of neighboring constructed and naturally formed mats. Planting species that occupy complementary niches should also minimize competition for key resources. 相似文献
162.
C. Lu I. K. Vasil 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1981,59(5):275-280
Summary Somatic embryogenesis was induced in proliferating leaf segments of Panicum maximum Jacq., cultured on Murashige and Skoog's nutrient medium containing 2,4-dichlorophenoxyacetic acid and coconut milk. The embryoids gave rise to plants on a medium containing gibberellic acid. The plants were successfully transplanted to soil and grown to maturity. Histological examination of proliferating leaves showed that the embryogenic callus tissue was formed by divisions in cells of the lower epidermis as well as the mesophyll tissue. The regenerated plants showed the normal chromosome number of 2n=4x=32.Florida Agriculture Experiment Station Journal Series No. 2775 相似文献
163.
W. W. Hanna C. Lu I. K. Vasil 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1984,67(2-3):155-159
Summary Plants were regenerated by somatic embryogenesis from cultured leaf segments of Panicum maximum Jacq. (Guinea grass). All plants were phenotypically similar to the donor plant from which expiants were obtained for culture. Examination of the cytological and morphological characteristics of the regenerated plants did not show any changes in mitotic (root tip) chromosome number, structural rearrangements of chromosomes, pollen stainability and morphological characteristics. 相似文献