Effects of transplanting small seedling under plastic film mulching on growth and development of flue-cured tobacco.

The results of field and pot experiments showed that transplanting 35~45-day-old tobacco seedlings under plastic film mulching could enhance the daily mean temperature of soil surface and 5~10 cm soil layer by 2~3 ℃ within 5 days after transplanting.Comparing with the conventionally transplanted large seedlings upon plastic film mulching,the transplanted small seedlings under plastic film mulching had poorer quality at transplanting and lower survival rate after transplanting,but they had early-developed root system with strong activity after transplanting,and their plants had stronger growth potential and better agronomic traits such as stem girth,plant height and maximum leaf area.There were no significant differences in yield per unit area,the output value per unit area,average price and superior leaf proportion of flue-cured tobacco among different treatments.