Studie On The Spore Tissue Culture And Shade Tolerance Of Three Ferns In The Eastern Mountainous Area Of Liaoning

Pteridophytes have high ornamental and ecological value,In order to strengthen the development and application of wild ferns and enrich the species of landscape plants,In this experiment,three kinds of ferns in northern areas: Adiantum pedatum,Dryopteris crassirhizoma,Dennstaedtia wilfordii spores and plants were used as test materials for tissue culture The factors affecting the spore reproduction of three fern species and the negative tolerance of the plants were studied under the conditions.In order to realize the rapid propagation of three kinds of ferns and know the best shade intensity,lay a foundation for the large-scale production and introduction of wild ferns.The main results of this test are as follows:1.Low concentration(100 mg·L^-1)GA₃ treatment had no significant effect on increasing the spore germination rate of three ferns collected that year.High concentration(300,500mg·L^-1)GA₃ treatment Inhibit spore germination and even prevent spore germination.2.The optimal medium for spore germination of A.pedatum is MS+NAA0.1mg·L^-1+6-BA0.1 mg·L^-1,spore germination rate is 57.00%.The optimal medium for the spore germination of D.crassirhizoma and D.wilfordii was MS and1/2MS,germination rates reached 69.16% and 34.35%,respectively.Low concentration NAA combined with 6-BA(both0.1 mg·L^-1)can increase the spore germination rate of A.pedatum.When the NAA concentration increased above 0.5 mg·L^-1,it inhibited the spore germination of A.pedatum,and the D.crassirhizoma and D.wilfordii fern not sensitive to the change of NAA concentration.When the concentration of 6-BA was higher than 0.5 mg·L^-1,the spore germination of three ferns was inhibited significantly.The best medium for A.pedatum proliferation and GGB induction was MS medium with 6-BA2.0 mg·L^-1,and the proliferation coefficient of protoplast could reach 4.02 after 40 days.MS medium with 6-BA1.0 mg·L^-1was the best medium for the proliferation of protoplasts of D.wilfordii.3.The germination of fern spores in the test varieties was light-type and could not germinate under dark conditions.4.Shading had no significant effect on the fresh weight and specific leaf weight of D.crassirhizoma;there was no significant effect on the fresh weight of fern leaves in D.wilfordii,but the specific leaf weight was significantly higher than other treatments under 70% shading conditions,and accumulated The largest amount of dry matter;the fresh weight and specific leaf weight of A.pedatum under 70% shading and 90% shading treatments were also significantly higher than those under 50% shading treatment.Low light is not conducive tothe accumulation of carbohydrates.The soluble sugar content of the three ferns was significantly higher than that of 90% treatment at 50% to 70% shading.5.With the increase of shade intensity,the chlorophyll content of all three ferns showed an upward trend,and the ratio of chlorophyll a/b decreased,showing adaptation to low light environment.6.Under the condition of strong light（50% shading）,free proline accumulation in D.crassirhizoma the MDA content reached the highest value,and it gradually decreased with the increase of shading intensity.The strong light adversely affected its membrane oxidation.Causes damage;MDA and free proline content in D.wilfordii are not sensitive to changes in light intensity,showing the strongest adaptive ability;A.pedatum accumulates the largest amount of free proline,MDA under 90% shade conditions Then it reaches the highest value under the condition of 50% shading,and gradually decreases with the decrease of shading intensity.Excessive and weak light will adversely affect its growth.7.Based on comprehensive indicators,the optimal shading intensity of D.crassirhizoma and A.pedatum is 70%,and the D.wilfordii can grow normally in the range of 50 ～ 90%.