Study On Leaf Photosynthetic Characteristic And Cold Resistance Of Some Cultivars Of Aglaonema Commutatun

Most of red leaves cultivars of Aglaonema commutatun have red leaf spots, veins orleaf margins, with a long ornamental period, and easy to form large blocks of colorlandscape features, and making up for deficiencies of the urban landscape and indoor shortflower season, and having broad applying prospects, but having fewer research on it.The anatomic structure of8varieties, that were,‘Silver King’,‘Lemon beauty’,‘Dragon fire’,‘Glitter’,‘Red Narrow’,‘Red Valentine’,‘Lady Valentine’,‘Sunrise’ ofAglaonema commutatum were observed and compared. The results were shown that, leavesof7varieties were kind of bifacial leaves but ‘Sunrise’ was kind of equilateral leaves, thepore were most distributed in lower eqidermis and main veins in the varieties of ‘SilverKing’,‘Glitter’ and ‘Lemon beauty’, while distributed in upper and lower epidemis in thevarieties of ‘Lady’ and ‘Red Valentine’, and distributed in the lower eqidermis in thevarieties of ‘Sunrise’,‘Red Narrow’ and ‘Dragon fire’. Upper and lower epidermis wascomposed of a layer of cells, and there were not relationship with different varieties in thesize of epidermis, having only one layer of palisade tissue in7varieties but ‘Sunrise’. Therelationship of leaf structure with coloring mechanism was also discussed.The net photosynthetic rate, transpiration rate, stomatal conductance, and concentrationof chlorophyll, carotenoids and anthocyanin conteint of leaf margin and mesophyll for8cultivars of Aglaonema commutatun, that were,‘Silver King’,‘Lemon Beauty’,‘Glitter’,‘Red Narrow’,‘Red Valentine’,‘Sunrise’, were determined respectively. The results wereshown that the net photosynthetic rate of red leave cultivars were more or less lower thangreen leave cultivars, the chlorophyll content has been found having a positive correlationwith net photosynthetic rate（r=0.953**）, and the optimal photosynthetic characteristicsmostof most varieties were obteined between600and1400μmol/(m2s).These index such as the plan appearance changing, chlorophyll content, permeability ofplasma membrane, and MDA content for13varieties of Aglaonema commutatun, that were4green leave cultivars and9red leave cultivars, were determined respectively after beingexperienced the natural cooling process in simply shed for2months. The results were shown that:1) the common green cultivers such as ‘Golden Jewelry’,‘Treubii’,‘Snowwhite’and ‘Silver queen’had poor cold hardiness ability.2) The cold hardiness of red leavescultivars may be divided into4categories from strong to weak,‘Peacock’ had the strongestcold hardiness in all cultivars, than these cultivars such as ‘Red Dragon’,‘Midnightgirl’,‘Red Valentine’,‘Lady Valentine’,‘Bond’,‘Glitter’,‘Polar Light’,‘Sweet Dream’,‘Sunrise’, had the2ndcold hardiness, while these cultivars such as ‘Dragon Fire’,‘LemonBeauty’and ‘Lipstick’ had poor cold hardiness ability somewhat like green cultivers.3) Itwas seemd that these red cultivars with the stronger cold hardiness ability had highercotaint of MDA, lower cotaint of chlorophyll, and vice versa.4) These red cultivars such as‘Peacock’,‘Red Dragon’,‘Midnight girl’,‘Red Valentine’,‘Lady Valentine’,‘Bond’,‘Glitter’,‘Polar Light’and‘Sunrise’ can be apllied for open field cultivation in Ghangzhou area, whilethese cultivars such as ‘Sweet Dream’,‘Red Narrow’,‘Dragon Fire’,‘Lemon Beauty’and‘Lipstick’ can be apllied for protected cultivation.