Tobacco Tray Nursery Key Technologies

In order to explore the key technologies of flue-cured tobacco seedlings,and offering good quality seedling for flue-cured production,using plastic tray,Substrate composed of soil,yard manure,perlite,and the mode of gap watering,the several aspects were analyzed including vary seedling material,tray standard,different water management,the disinfectants effect to seedling tray and clipping leaf tools.At the same time the data were got including the growth characteristics in different growing stages and after transplant,the seedling physiologic characteristic,seedling qualities index,and the tobacco leaves qualities in the field.The research results showed:1 Influences of substrate contents on tobacco seedling growth in tray system.The higher emergence rates will get if the soil without disease is more than ashes.More yard manure does not benefit emergence of seedling,but benefit tobacco plant day matter accumulation in up ground and underground,and enhance seedling qualities.The substrate contents that soil without disease,yard manure and perlite equal to 5,3 and 2 is fit to seedling growth,getting higher emergence,faster growth speed,and better seedling quality, and this seedling is very fit to transplant.Using this substrate content,the seedling per plant can get 6.3 cm stem highness,1.7 cm stem perimeter,8.6 leaves,1.25 g(0.094 g) root fresh weigh(dry weigh),0.57 g(0.053 g) stem fresh weigh(dry weigh),2.90 g(0.236 g) leaves fresh weigh(dry weigh).2 Influences of tray standard on seedling.The deepness and substrate volume per hole will effect seedling growth.The 74 hole and 51 hole tray including 6-6.5 cm deepness benefit flue-cured seed emergence,young seedling growth and inducing transplanting seedling qualities.Both of them can nurse haleness transplant seedling with high quality, upgrowth root,sturdy stem.3 Influences of nutrition on seedling growth in tray system.There is good correlation between fertilizer quantity and nutrition content in substrate itself.Under the test substrate condition,fertilizer concentration per time from 150 mg/kg to 200 mg/kg can nurse higher quality transplant seedling.Fertilizer concentration per time up 200 mg/kg can enhance seedling's stem and leaf,but restrain root growth.4 Influences of Water deepness on flue-cured young seedling.The water content in substrate controlled by water volume in tray strongly effects emergence of flue-cured seed, the growth of seedling,and transplant seedling qualities finally.Before emergence of seedling,more water will get shorter emergence days.But after emergence,less water will benefit seedling growth,shorten seedling days.The water deepness with 2.5cm or so can get 90%and more emergence rates before emergence,bat after emergence the deepness with 0.5-1.5 cm water can benefit seedling growth and nursing stronger seedling.5 Influences of several disinfector on sanitizing effecting of seedling tray and clipper tools.Zhaoguan from 30 to 100 times can passivity the virus on seedling slim side root and slim bar leaf,and the 60 times Zhaoguan can totally passivity the virus in the juice of disease leaf.60 times Zhaoguan with 8%Ca(ClO₃)₂ can kill all of the virus in 20 minutes in TMV without protect of the leaf organ.Some strength Zhaoguan passivity TMV in slim root more than that of leaf,but the Ca(ClO3) is the other way round.6 Influences of various styles of seedling on tobacco plant growth and tobacco qualities.The photosynthesis rates and rising rates the tobacco plant from tray system and float system slow down less than that of traditional seedling system,but the chlorophyll a+b and root vigor were opposition due to the special seedling environment and management styles.That is the root in water and balanced nutrition,and exceptive clipper and smelting technology.The tobacco plant from tray system abloom 7 days later than traditional seedling system,and more 3 leaves than traditional system.About the chemistry content in tobacco leaves,there were nicotine,reducing sugar and total sugar.Compared with traditional seedling system,the leaves related with tray system have lower nicotine in middle and upper leaves,higher reducing sugar,and then there were obvious on upper leaves.