Studies On Regeneration Of Strawberry Leaves In Vitro Culture

Factors affecting the high efficient regeneration of adventitions shoots were studied by using lfaves of in vutro cultured shoots of widely used strawberry culturar "Toyonoka" and "redrich", including genotypes, basal media, culture conditions of subculture shoots, methods of inoculation, the length of darkness, light intensity , plant growth regulators and AgNO3. The high efficient regeneration system of adventitious shoots was established and the critical concentration of kanamycin was examined.Main achievements were as follows:1.For "Toyonoka" , newly and fully unfolded young leaves from sub-cultured for 30 to 35 days under 20001x light intensity were most responsive to regeneration.2.Regeneration efficencies were same on the basal medium of MS and MS+B5, It indicated the influence of B5 organic matters on induction of leaf disks was not substantial for the two cultivars. But Regeneration efficencie of "Toyonoka" was higher in the LS than others. So LS was the best basal medium for "Toyonoka"3. Cutting the leaf into two parts was an appropriate way of inoculation. Regeneration efficentcies were same when the adaxial surface and abaxial surface were kept in contact with the media surface for the two cultivars. A period of darkness was necessary to the high efficient regeneration system of adventitious shoots.4. TDZ combined with NAA increased regeneration efficiency dramatically for "Toyonoka" , the optimal shoot regeneration media was LS+TDZ1.5~ 2. 0mg/L+NAA0.05 mg/L5. AgNO3 restrained formation of callus, and Ag+ could not increase regeneration of "redrich" leaves.6. Kanamycin was proved to be an efficient inhibitor for regenra-tion of strawberry leaves. For "Toyonoka" , the critical concentration of 50mg/L, kanamycin could be used to choose transplanted shoots.