Study On Key Factors Affecting Cold Storage Of Tulip Bulbs

Tulip is a famous bulblous flower. The demand for ornamental application is increased continuously every year, but the domestic tulip still face to some problems, such as degenerated seriously, poor quality, less variety, can not supply the domestic market, and therefore dependence on imports. To achieve the domestic production of bulb, the key issue of bulb storage must be solved. In this paper, the effects of moisture content and tunic damage on cold storage of tulip bulb "Apeldoorn" were studied, The results showed that:1. The tulip bulbs with moisture content 66.5 %, 64.4%, 62.8 % were obtained by drying in the air. in cold storage period, the decrease of fresh weight reduced and the increase rate of circumference increased along with reduction of moisture contents. The tendencies of respiration rate of bulbs with different moisture content were consistent, the respiration rate decreased at the first, then increased in 8 weeks, but remain at a relatively low level. Soluble sugar content increased, and the bulbs with low moisture content maintained at a high level, and starch content declined slowly in the storage period, the bulbs with moisture content 66.5% was lowest, went against long-term storage, growth of bulbs after planting showed that the plant height and flower height of bulbs with low moisture content were better than high moisture content's. So the bulbs with moisture content 62.8% were best.in the storage.2. According to the condition of tunic damage,the Tulip bulbs will be divided to: the bulbs of 1/3 tunic damage, the bulbs of 2/3 tunic damage, the bulbs of tunic damage completely, the bulbs of no tunic damage were control. In cold storage period, the fresh weight reduced, and the circumference increased,and the more serious of tunic damage ,the bigger of fresh weight reduced and the smaller of circumference increased .At the begin of the storage,the respiration rate of each group increased sharply.and declined rapidly, men began to rise in 12 weeks,the respiration rate of the bulbs of tunic damage completely dropped sharply to the lowest level, this may be the performance of respiration weakness. The more serious of tunic damage, the higher of SOD, POD,CAT activity and MDA content. In cold storage period, the PPO activity of control was lowest,and the activity of the bulbs of tunic damage completely was highest. Cultivation tests showed that tunic damage of bulbs did not affect the germination, the rate of flowering of bulbs of tunic damage completely reduced. The more serious of tunic damage, the lower of plant height and flower height. This showed that the tunic damage of Tulip bulb closely related to the storage quality.