温度对香蕉不定芽生长及抗氧化酶活性的影响

Effects of different temperatures on growth and root antioxidant enzyme activities of banana adventitious bud

为探明温度对香蕉不定芽生长及根系活力的影响,以巴西香蕉（Musa paradisiaca）为材料,在人工气候箱条件下研究温度对香蕉不定芽生长及抗氧化酶活性的影响。结果表明：SOD活性呈现上升-下降波动变化,POD活性先上升,培养15~20d达到最高后下降,培养45d后又缓慢上升,CAT活性整体先下降,培养45d后上升;在30℃以内,随温度升高,根系活力逐渐增加,培养20d后游离脯氨酸含量随温度升高而上升,培养50d开始下降,MDA含量先逐渐下降后上升,培养20d和45d较低;30℃最适宜香蕉不定芽生长,此条件下培养25d根系活力达最高（11.92mg/g·h）,游离脯氨酸（58.76μg/g）和MDA含量（7.15nmol/g）都较低,根茎叶生长旺盛（苗高5.02cm、叶数3.64片、根数4.63条、根长4.91cm）,是最适宜移栽的时间;培养45d根系活力为2.33mg/g·h,游离脯氨酸（94.83μg/g）和MDA含量（9.83nmol/g）都较低,根茎叶生长旺盛（苗高6.15cm、叶数4.97片、根数6.01条、根长6.06cm）,是次适宜移栽的时间。30℃最适宜香蕉不定芽的生长,培养25d是最适宜移栽的时间。

To clear the effects of temperature on the growth of banana adventitious bud and its root activity,taking ‘Brazil＇ banana （Musa paradisiaca） as materials in the artificial climate chamber conditions. The results showed that SOD activity first increased and then decreased. POD activity first elevated and reached the highest in the 15-20 d,and then declined and slowly improved after 45 d. CAT activity first fell and increased after 45 d. At 30℃,with the increase of temperature,root activity gradually increased and the free proline content after 20 d rose and began to drop at the 50th d. MDA content decreased gradually and then increased,was lower at the 20th d and the 45th d. Banana adventitious bud grew best at 30℃. At the 25th day under this condition,the root activity reached the highest （11.92 mg /g·h）,the contents of free praline （58.76 μg/g） and MDA （7.15 nmol/g） were low,and vigorous growing plantlets （height 5.02 cm,leaf numbers 3.64,root numbers 4.63±0.06,root length 4.91 cm） were most suitable for transplanting. At the 45th day under this condition,the root activity reached higher （2.33 mg /g·h）,the contents of free praline （94.83 μg/g） and MDA （9.83 nmol/g） were low,and vigorous growing plantlets （height 6.15 cm,leaf numbers 4.97,root numbers 6.01,root length 6.06 cm） were suitable for transplanting. The results suggested that 30℃ was most suitable for the growth of banana adventitious bud and the most suitable time for transplanting was to train for 25 days.