| Effects of roots exudates (RE) and decomposing matter of strawberry plants on rooting plant in vitro of strawberry were studied, and the methods of controlling the replant disease of strawberry were compared. Main achievements were as follows:1. The tissue culture methods were used to analyze the effects of roots exudates on rooting plant in vitro of strawberry (cv. Allstar). 50% RE and 100% RE were supplied in the 1/2 MS medium. Results showed that RE remarkably restrained the growth of rooting strawberry plants, reduced SODase activities, chlorophyll content and root TTC reducing activities, increased cell membrane relative permeability in leaves of rooting plants, and decreased the resistant ability of strawberry plants to the disease. Moreover, The higher concentration of RE supplied in the medium was, the bigger effects on rooting plant were. Therefore, it can be concluded that RE of strawberry was one of the factors inducing replant disease in strawberries.2. The effects of plant decomposing liquid on rooting plant in vitro of strawberry were also studied under tissue culture conditions. The results showed that rooting strawberry plants treated by plant decomposing liquid had lower plant height, shorter length of root, slighter plant fresh weight and root fresh weight, weaker SODase activities and root TTC reducing activities, lower chlorophyll content, higher MDA content and bigger cell membrane relative permeability in leaves of rooting plant than that treated by distilled water. The higher concentration of the same plant decomposing liquid added to culture medium was, the more obvious these effects were. In addition, effects on strawberry of three or six months decomposing liquid of the mixture of stem and leaf were biggest, that of one-month or three months root decomposing liquid and one-month decomposing liquid of the mixture of stem and leaf were bigger than that of six months root decomposing liquid. But the decomposing liquid of the strawberry replanted soil hadn't any significant influence on strawberry, despite how long the decomposing time was. Therefore, it was found out that the decomposing matter of strawberry plants was related to replant disease in strawberries.3. In this part of the experiment, different methods of controlling strawberry replanting diseases were compared on the soil with continuous 3 years cropping of strawberry (cv. Toyonoka). The soil treatments were soil sterilized with the mixture of 38% Formaparison and Potassium permanganate, soil sterilized with solar heat and unsterilized soil. Strawberry plants were inoculated with Glomous mosseae, Mycokick, AS818. In addition,another treatment was tested with root protecting membrane buried in the sterilized solar heated soil. The unsterilized soil and uninoculated strawberry plants were used as control. The results showed that the above controlling methods of replant disease in strawberries not only improved the growth, but also enhanced the physiological activities of replanted strawberries. Soil sterilized with solar heat + root protecting membrane increased dry weight of plant by 160.00% compared to control. Soil sterilized with solar heat+ Mycokick+ root protecting membrane could remarkably increase leaf area, length of petiole, height of plant and length of root by 333.33%, I01.96%192.55% and 205.83% respectively; enhance yield per plant by 76.07%, reduce death rate of planting by 157.41%; improve relative controlling effect by 64.24% as compared with control, respectively. It could be summarized that the root protecting membrane could lighten injury of pest and nematode in the soil to the strawberry plants and soil sterilized with solar heat+ Mycokick + root protecting membrane could significantly improve resistant ability of strawberry plants to the replant disease.4. Effects of RE, plant decomposing matter, Glomus mosseae, Mycokick, ASS 18 and root protecting membrane on chlorophyll content and SODase activities in leaves of replanted strawberry were studied, and the effects of all kinds of... |
