Study Of Strawberry Intensive Seedling Key Technology Under High Temperature

Strawberry belongs to the rosaceae perennial herbaceous plants; it is fond of cool climate. Strawberry cultivation area is increasing year after year in our country, but we need transplant strawberry seedling every year, so the demand of strawberry seedlings is very large, and strawberry seedlings are in high temperature season. At present, the strawberry seedlings production is extensive outdoor production in general, so we must urgent need of intensive production, which could improved the quality of strawberry seedlings. Therefore, with strawberry stolons seedlings as material, through the morphological, physiological, seedling rate and seedling index and so on, selecting the proper strawberry seedling substrate, temperature, light and rooting agent for high temperature season, the main research results were as follows:1. By comparing the effects of 3 single substrate and 4 kinds of mixed-substrate on the growth and physiological characteristics of strawberry seedlings, the suitable substrate for high temperature season was selected, using the Fragaria×ananassa Duch. cv.’Benihoppe’as experimental material. The results showed that the photosynthetic rate and nitrate reductase activity of strawberry seedling were significantly higher than other treatments under the substrate E (cotton seed hulls:perlite=2:1), and the seedlings were growing well, the seedling plant fresh weight under the substrate E was 42% higher than F treatment (rice husk:turf:chicken manure=1:1:1), the seedling plant dry weight under the substrate E was 30% higher than D (turf:perlite=2:1). Comprehensive comparison, during the high temperature season, the mixed-substrate (cotton seed hulls:perlite=2:1) was more suitable for strawberry nursery, which was conducive to the growth of strawberry seedlings.2. With increasing temperature, nitrogen metabolism key enzyme activity showed the trend of first increased and then decreased in strawberry seedling leaf under the 20 to 35℃, for example nitrate reductase, glutamine synthetase and glutamate synthase. Chlorophyll content and photosynthetic rate of strawberry seedling leaf had also similar trends; Leaf relative conductance rate and the content of MDA also increased. At the 25℃ temperature, the chlorophyll content and photosynthetic rate of strawberry seedlings was the highest, and the nitrogen metabolism level highest; Leaf relative conductivity and MDA content were lower. So strawberry seedlings rate was the highest under the 25℃.3. During the high temperature season, natural light led to the stomatal closure, the intercellular carbon dioxide content and water use efficiency decreased, therefore, to a certain extent, which inhibited the growth of strawberry seedlings. Shading treatment not only improve strawberry seedling leaf chlorophyll content and photosynthetic rate, water use efficiency, apparent quantum efficiency and carboxylation efficiency, transpiration rate and stomatal conductance was higher, which could improve the strawberry seedlings photosynthetic rate, promote seedling growth, in the shoot and root growth of good, fresh weight value is bigger; the shading rate was 45% in the treatment of strawberry nursery effect best, but shading rate is too high is not conducive to the growth of the seedlings of strawberry. Therefore, in high temperature season, seedling, the treatment of 45% shading rate was better to growth and cultivation of strawberry seedling.4. Using’IBA’,’863’and’KPK’three different rooting agent, those can significantly promote the growth of strawberry seedlings roots, which showed that the number of root and root surface area increased, especially the strawberry seedling root tip number is 21.5 by the rooting agent’863’ processing, and plant root surface area was 30.5cm2; In the aspect of promoting root length had a similar effect. Rooting agent not only promoted the root, also promoted the accumulation of dry matter. In short, rooting agent improved the summer strawberry seedling rate and seedling index. So we suggested that rooting agent’863’was better to strawberry seedling in high temperature season.5. Comparing with conventional seedling, tray intensive seedling not only could improve the quality of strawberry seedlings and after transplant seedling survival quickly, which increased production and increase the profit of the cultivation; the results showed that per 667m2 could increase the efficiency by more than 11%. Therefore, the technology of tray intensive seedling could be widely used in production, and the application prospect is good.