Study On Propagation Technology Of Virus-free Production Seedlings Of Strawberry

With the improvement of people’s living standards,the demand for fruits and vegetables with high nutritional value is increasing.As one of the representative fruit vegetables,the development of strawberry is particularly rapid.Therefore,the demand for seedlings is also increasing.However,asexual propagation of seedlings of seedings by the traditional methods are far from meeting the needs of production and development.Moreover,the cultivated seedlings are generally infected with viruses,causing excellent varieties to degenerate and resistance declining,the output drops,and the quality deteriorates.So cultivating non-toxic strawberry seedlings is the development trend in strawberry cultivation.The methods growing seedlings affects quality of the seedlings.Conventional open field,elevated facility,and trough substrate growing seedlings methods have their advantages and disadvantages respectively in present.Therefore,the experiment effectively combined the strawberry stem tip tissue culture technology with the production seedling breeding technology,obtained high-quality detoxified original seedlings through strawberry tissue culture and rapid propagation technology,and compared the effects of different breeding methods on the growth and development of plants,the advantages and disadvantages.It aims to provide theoretical support for the selection of the best breeding methods for strawberry production seedlings.The results are as below:1.Comparing the sterilization effect of strawberry stem tips in 0.1% Hg CI₂ for different treatment time,it is found that the optimum time was 8 min for both ‘Hongyan’ and ‘Suizhu’,and the survival rates were86.70% and 60.00%,respectively.2.The best media for strawberry shoot tip differentiation were screened.For ‘Hongyan’ variety,the best induction medium was 0.3 mg/L6-BA+0.1 mg/LNAA,the survival rate was the highest with up to82.30%;The subculture medium was 0.5 mg/L6-BA+0.1 mg/LNAA,its proliferation coefficient was the highest with 5.20;For rooting the optimum medium is 1/2MS,and the rooting rate is the highest with 100%.For ‘Suizhu’ variety,the best primary medium was 0.5 mg/L6-BA+0.1 mg/LNAA with the highest survival rate of 93.33%;In the subculture medium of 0.5 mg/L6-BA+0.2 mg/LNAA,the proliferation fold is as high as 4.21;The rooting rate is as high as 100% in the rooting medium of 1/2MS+0.1 mg/LNAA.3.Different propagation methods have different effects on strawberry plants.In general,the overall effect of seedlings from protected facilities was better than that from traditional open-field.Comparing efficiency of seedling propagation,the number of stolons per plant of ‘Hongyan’ reached 10.51 by the trough substrate breeding method on 120 days after planting,and the number of seedlings per plant reached33.30.In terms of the survival rate of seedlings transplanted,the survival rate of the seedlings from trough substrate and elevated cutting all reached 100%,and which was higher than that from open-field.Comparing the agronomic characteristics of the seedlings,the growth status of seedlings from trough substrates is good,and there is no significant difference in stem thickness and petiole length from elevated cuttings,but both of them were different significantly to seedlingsfrom open field in plant height,leaf area,chlorophyll content an so on.In terms of biomass,above ground fresh weight and dry weight,under ground fresh weight and dry weight of strawberry seedlings from trough substrate were higher than that from other two methods with14.87 g/plant,3.83 g/plant,4.38 g/plant and 1.92 g/plant,respectively.Inspecting the occurrence of diseases and insect peststhe incidence rate of powdery mildew and anthracnose in the seedlingsfrom tall frame was the lowest with 15% and 4%,respectively,however,there is no significant difference to seedlings from trough substratesand the incidence rate of the two diseases in seedlings from open field is the highest.As to phenology,the flowering and fruiting stages of seedlings from trough was earlier than those from tall-frame and open field.In the aspect of fruit quality,the seedlings from three seedling growing methods have not obvious differences except for acidity.On the whole,the trough-type substrate breeding method is the best.