Studies On Tissue Culture And The Response To NaCl Stress Of Seedling Of Salix Matsudana×Alba

The coast of our country is a natural resources treasure-house, the potential of development in forestry is very big.Take Jiangsu province as an example, the whole circumlittoral pool area has 7,080,000 hm2, have a national pool 20% of total area around or so, among them 140,000 hm2 can be provided as the area of development in forestry.Salix matsudana×alba is a new cross breed variety with high resistance to wind and salinity or alkaline soil, so it was suitable for afforestion in special conditions such as salina. It was introduced from New Zealand, breeded in USA.The understanding for this new product is still not overall currently, especially in our country artificial cultivation field,at present,current situation and prospect for this new speices is still a blank.Its economy value of the exhumation is also not thorough.Therefore,the improvement to the coast of Jiangsu is going to whole country of saline alkali land, protect a circumlittoral pool ecosystem environment, greenery and beautification seashore city, raise the people's economic income,to which, the enlarging developments of making use of this new speices will contribute greatly.The potted plant in salinity stress and tissue culture of Salix matsudana×alba were studied in this thesis, in order to discuss the response of cutting seedling to the salinity stress and found out applicable method for tissue culture; The callus induced in the process of tissue culture was also studied on its resistance to the salinity stress, expecting obtaining mutation with high salinity resistance.These can provide practice foundation to Salix matsudana×alba and the other cross breed varieties.The analysis showed that:1.As the concentration of salinity and the time increased, the survival rate, the growth of height and caliper all descended. After 20d NaCl stress, seedlings in treatment 1.0% all died, those in 0.8% and 0.6% partly died(die rate:88.9%, 11.2%), but those in 0.4% and 0.2% grew very well.2.The relative conductivity of leaf ascended with increasing NaCl concentration in the late treatment(after ten days).3.The root vigor, the content of chlorophyll first ascended then descended with increasing NaCl concentration.4.When NaCl≤0.4%,the activities of POD and SOD in leaves ascended more or less,when NaCl≥0.6%,the activities of POD and SOD quickly descended with increasing NaCl concentration.5.The content of soluble sugar descended with increasing NaCl concentration. The content of proline ascended when NaCl≤0.4%,but descended when NaCl≥0.6%.6.The results of tissue culture showed that the stems with buds were the best explants for tissue culture, and the best sterilization method for explants was soaked in ethanol for 15s then HgCl for 8min. The tube culture could avoid cross contamination in inoculation and Vc could prevent the explants from browning; but in subculture, the jam bottle culture was propitious for the callus multiplication, 6-BA and NAA both are 0.3mg·L-1, the callus could multiplicate and differentiate into stem and leaves.7.The callus could grow well in the culture medium with NaCl concentration of 0.5%, and could grow commonly in that of 0.75%, but would browned and gradually die in that of 1.0%. The callus with salinity resistance to NaCl concentration of 0.1% was expected to be obtained.