Studies On The Selection Of Suitable Bletilla Plants In Shanghai

The present thesis using analytic hierarchy process?AHP?is mainly about resource evaluation of twelve Bletilla germplasms,the resource evaluation system included ornamental characteristic,adaption,cultivation and management.Resistance experiments such as moisture resistance?salt tolerance?alkali resistance?sunburn resistance were studied on twelve Bletilla germplasms.Within an artificial system with excessive moisture of 80%,Bletilla 5 physiological parameters including malondialdehyde?MDA?contents,proline(P_ro)contents,cell membrane permeability,chlorophyll contents,and root dehydrogenase activity were monitored at 12,36,and60 hours post treatments.Within artificial system with excessive salinity of 0.073?0.219?0.365%,Bletilla physiological parameters including net photosynthetic rate?P_n?,stomatal conductance?G_s?,intercellular CO₂ concentration?C_i?,osmotic adjustment parameters such as soluble sugar contents?Ss??proline contents,cell membrane permeability,root-shoot ratio were monitored.Alkali resistance experiment were examined to determine their tolerance to excessive alkali,alkaline soil using NaHCO₃ and NaOH mixing solution into PH 8?9?10.Bletilla physiological parameters including net photosynthetic rate,cell membrane protection,soluble sugar contents,proline contents,biomass,plant water capacity,root-shoot ratio were monitored.Bletilla evaluation of ornamental characteristics in morphology,adaption in morphology and physiology,cultivation and management in manpower and time input of management.Comprehensive evaluation in Bletilla is going on accurately,screening out species with high ornamental value and growth well.The research is beneficial to promote the application of Bletilla in garden and horticulture,and expand cultivation and planting.It can not only provide new materials for germplasm innovation,but also enrich the diversity of garden plants,so as to form a better landscape and increase ecological benefits.The main findings are as follow:1?Comprehensive evaluation system of Bletilla germplasm resources as follow:three criterion layers included ornamental characteristic?0.453??adaption?0.306??cultivation and management?0.241?,thirteen index layers included flower color?0.315??florescence?0.164??amount of flowers?0.176??lip color?0.105??scapes showed roughness?0.116??flower show degree?0.124??growth vigor?0.246??moisture resistance?0.219??salt tolerance?0.158??alkali resistance?0.158??sunburnresistance?0.219??plant reproduction?0.362??degree of difficulty in cultivation and management?0.638?.2?The result of comprehensive evaluation screen out three germplasms with high ornamental value and growth well are Bletilla striata from Shanxi?Bletilla striata from Jiangxi?Bletilla striata from Chongqing.Comprehensive evaluation in ornamental characteristic?adaption?cultivation and management of Bletilla,the range of grades from high to low is Bletilla striata from Shanxi?Bletilla striata from Jiangxi?Bletilla striata from Chongqing?Bletilla striata from Hubei?Bletilla ochracea from Hubei?Bletilla striata from Anhui?Bletilla formosana from Yunnan?Bletilla striata from Sichuan?Bletilla ochracea from Guangxi?Bletilla ochracea from Shanxi?Bletilla formosana from Taiwan?Bletilla formosana from Sichuan.3?The twelve Bletilla germplasms in adaption of comprehensive evaluation had slight salt and alkali resistance,and were not sensitive to salt-alkali soil.The results showed that lower concentration of salt concentrations?100and 300 mmol·L^-11 of salinity?promoted the growth of Bletilla,improved net photosynthetic rate?P_n?and stomatal conductance?G_s?,increased the content of soluble sugar?SS?,proline?Pro?of Bletila,but reduced the intercellular CO₂ concentration?C_i?and membrane permeability.The higher salt concentration?500 mmol·L^-11 of salinity?had toxic effects on Bletilla.4?The study indicated that the Bletilla plants reached their maximum of regulatory capacity at 36 hr post treatment.Most of the examined Bletilla showed an initial decrease followed by an increase in the levels of MDA and cell membrane permeability;meanwhile,an initial increase followed by a decrease was observed for Pro and chlorophyll contents as well as for root dehydrogenase activity.