湘南烟区不同增温方式培育烤烟壮苗研究

Breeding of robust seedling of flue-cured tobacco in different heating systems in Southern Hunan

为克服湘南烟区冬季漂浮育苗受低温寡照影响导致烟苗生长发育不良的障碍,培育抗逆性强的高茎壮苗,研究了采用加盖小棚并加热棚内空气、提高育苗池水温、加盖小棚3种增温方式对烤烟漂浮苗农艺性状及主要生理指标的影响。结果表明,加热棚内空气、提高水温比对照和加盖小棚处理可缩短育苗期10～20 d;加热棚内空气和提高水温处理的漂浮苗叶宽、茎围、地上部鲜重和根系鲜重均明显大于对照和加盖小棚处理,但茎高小于加盖小棚处理和对照;加热棚内空气和提高水温可明显提高漂浮苗的根系活力;增温方式处理的漂浮苗游离脯氨酸含量均极显著低于对照;提高水温处理的漂浮苗叶片叶绿素含量极显著高于对照和加盖小棚处理,加热棚内空气和提高水温均能有效促进烟苗的生长,提高烤烟壮苗率。

To avoid growth retardation of tobacco floating seedling caused by low temperature and short photoperiod in Southern Hunan in the winter, and to cultivate high-stem robust seedling with strong resistance to unpleasant environmental conditions, three systems were used to increase temperature in the workplace, namely, small shed plus air-heating in the shed, seedling pond with increased temperature and small shed. And the agronomic traits and physiological indexes of flue-cured tobacco floating seedling were observed. The results show that heating air or water temperature treatment can reduce breeding period byl0-20 d comparing to shed treatment and CK. Leaf width, stem circumference, fresh weight of the above-ground part and root of floating seedlings from air-heating or water temperature increased treatment were greater than but the stem height were shorter than those of shed treatment and CK. Increasing the temperature of the air and the water can obviously improve the root vigor of the floating seedling. Free pro-line content of CK in each growing period was significantly higher than those in three temperature-increased treatments. Chlorophyll content of floating seedling with increased water temperature was significantly higher than those in small shed treatment and CK. Conclusively, increasing air or water temperature can effectively promote the growth of tobacco seedlings and raise the rate of robust seedling of flue-cured tobacco.