Root-promoting Seedling Raising Technology And Its Effect On Drought-resistance Of Seedlings Of Quercus Mongolica

Quercus mongolica is a zonal tree species in western Liaoning province. However, the root growth of Q. mongolica seedlings is the main root growth, lateral roots are slender and fibrous roots is extremely few.Then in afforestation experiment it was found that the survival rate of Q. mongolicain tree planting was very low and afforestation is difficult in the arid and semi arid areas.In this paper, discusst the impact of root and seedling growth seedlings as well as drought tolerance on Q. mongolica seedlings by physical treatment, application of plant growth regulators and mycorrhizal regulation of three methods and to provide a theoretical basis and method, which is cultivate seedlings of Q. mongolica, improve the the survival rate of Q. mongolica seedlings planting was in the arid and semi arid areas. The results are as follows:1.The physical treatment, radicle-breaking off method can significantly promote the seedling growth of Q. mongolica seedlings. In seedling hardening period, the height of Q. mongolica seedlings by radicle-breaking off method is 12.89cm, the diameter is 4.20mm, the root length thanlcm is 34.1 number, the root length than 5 cm is 5.1 number. Q. mongolica by multiple-radicle method can not promote the height and diameter growth, but it can significantly increase the seedlings root growth. In seedling hardening period, the root length thanl cm of Q. mongolica seedlings by multiple-radicle method is 32.9 number, the root length than 5 cm is 6.8 number.2.The growth regulators treatment, four treatments which are 300mg·1-1 of IBA,50mg·1-1 of NAA, 200mg·1-1 of ABT3 and 100+100 mg·1-1 of NAA+ IBA can significantly promote the seedlings and root growth. Considing the impact of on seedling morphology by four treatments, the most significant effect on the growth of Q. mongolica seedlings is 300 mg·1-1 of IBA. In seedling hardening period, the height of Q. mongolica seedlings by 300 mg·1-1 of IBA is 14.33cm, the diameter is 5.64mm, the root length than lcm is 61.0 number, the root length than 5 cm is 19.7 number.3.The Pisolithus tinctorius which is mix ectomycorrhizal fungi 017 treatment is best effect the seedling growth of Q. mongolica. In seedling hardening period, the height of Q. mongolica seedlings by Pisolithus tinctorius which is mix ectomycorrhizal fungi 017 is 14.84cm, the diameter is 5.80mm, the root length than 1cm is 65.4 number, the root length than 5 cm is 8.0 number.4. Comparing effect Q. mongolica seedlings growth by the optimal method of 3 measures which is physical, growth regulators and mycorrhizal fungi material, the Pisolithus tinctorius which is mix ectomycorrhizal fungi 017 is the best method of effecting the growth on Q. mongolica, by follow is the 300mg'1-1 of IBA method, the less effective methodis radicle-breaking off method.5. The trend of photosynthetic rate under six promoting seedlings root method on Q. mongolica is similar, which is showed a bimodal curve. In this experiment under the different concentrations of PEG stress, the photosynthetic rate of promote root treatment on Q. mongolica seedlings in the order are:the Pisolithus tinctorius which is mix ectomycorrhizal fungi 017> growth regulator>the physical treatment.The protetctive enzyme(SOD, POD, CAT) with the increase of stress time activity of Q. mongolica seedlings which deal with six root promoting method is increased firstly and hen showed a downward trend. The protetctive enzyme of SOD and CAT activity reached the maximum stress at the third day; the protetctive enzyme of POD activity reached the maximum stress at the forth day. In different water stress the protective enzyme activities(SOD, POD, CAT) of promote root treatment on Q. mongolica seedlings in the order are:the Pisolithus tinctorius which is mix ectomycorrhizal fungi 017> growth regulator> the physical treatment.It can conclusion that the best method to promote the Q. mongolica seedlings growth and drought tolerance enhancement is the Pisolithus tinctorius which is mix ectomycorrhizal fungi 017. In the culture of drought and the eco- Q. mongolica seedlings, Pisolithus tinctorius which is mix ectomycorrhizal fungi 017 should priority used, or use 300mg·1-1 of IBA treatment seeds, and other promote technical measures.