Breeding And Utilization Of Ornamental Sweetpotato (Ipomoea Batatas (L) Lam.)

It is a novel idea for sweetpotato to be used as an ornamental plant. Ornamental svveetpotato has been researched and used in USA, Cananda and some other developed countries, while little research on ornamental svveetpotato has been done in China. Therefore, a systematical research on breeding and utilization of ornamental sweetpotato was done in this paper:1. There are several evaluation indexes for ornamental plants, including ecologic adaptation, gardening efficiency, ornamental character, diseases and insect resistance, pollution resistance and economy efficiency, but ecologic adaptation is one of the most important indexes. Tolerance to low light and low temperature are two very important indexes of ecologic adaptation. Investigation has been made on sweetpotato tolerence to low light and low temperature. The results showed that there was a different adaptation to low light and low temperature between two varieties tested. Both varieties had higher water content with 176 μ mol · m-2 · s-1 light intensity treatment than that of 44 u mol · m-2 · s-1 treatment. SOD activity of two varieties decreased obviously as light intensity decreased. POD activity of L80-62 increased as light intensity decreased. However, POD activity of NC193 was the highest at 8800 Lux light intensity and the lowest at 352 u mol · m-2 · s-1 light intensity. In the cold resistance experiment, SOD activity, POD acrivity, and MDA concentration of two varieties increased firstly and then decreased and even declined to previous level after 72 hour chilling. SOD activity, POD acrivity, and MDA concentration of two varieties was lower at 10 ℃ than that of 5 ℃ . Protein concentration of two varieties increased gradually firstly and decreased after 48 hours treatment. However, at 72 hours chilling treatment, protein contration of two sweetpotato varieties re-increased. Protein concentration of sweetpotato was higher at 10℃ than that of 5℃ treatment. SOD activity, POD activity, protein concentration, and MDA concentration of L80-62 was higher than that of NC193 at 5℃. POD activity and protein concentration of L80-62 was higher than that of NC193 at 10℃ while SOD activity and MDA concentration of L80-62 waslower than that of NC193.2. According to the newest issue of sweetpotato descriptors and data Standard in our country, evalution method and indexes of ornamental sweetpotato has been put forward, which including morphological characters, such as upper leaf color, leaf color, stem color, leaf shape, stem thickness, vine length, and plant shape and ecolopical characters such as naturally flowering,...