This article reported the induction, purification and identification of a pathogenesis-related protein from the intercellular fluids of cucumber seedlings, which were treated with benzothiadiazole (BTH) or
Pseudoperonospora cubensis. Our results demonstrated that both BTH treatment and Pseudoperonospora cubensis inoculation could induce the exp ression of a 27 kD p rotein in intercellular fluids of cucumber leaves. This protein was purified by electroelution combined with SDS - PAGE, and analyzed by MALDI-TOF MS. The obtained pep tide mass fingerp rinting ( PMF) was searched in the protein data bank, indicating that it was an acidic chitinase. This was confirmed further by the assay of chitinase activity andWestern blotting.
Tetrap loidswere successfully induced from in vitro plantlets of diploid Gerbera jamesoniiBolus‘Cabana’and‘Dalma’(2n=2x=50) by dipping shoot tip s with colchicine. Colchicine at a concentration of 0.02% , 0.05% , 0.10% were tested for 24, 36 and 48 h. The results indicated that the most efficient
condition for inducing tetrap loids was treated with 0110% colchicine for 48 h. The highest mutation rate of‘Cabana’and‘Dalma’was 16% and 10%, respectively. As a whole, gerbrea shoots seemed be not sensibility to colchicines. Mutation budswere screened bymorphological app raisal, stomatal and cytological identification. The chromosome number of part mutants have doubled to 100 (2n=4x=100). As compared with diploid, tetraploid of Gerbera jamesonii Bolus was characterized by larger stoma area, larger flower head,thicker leaves color, leaves tend to round, thicker leaves, larger stem diameter and anthocyanin coloration of peduncle baseswere obviously strong. Finally, over 200 and 300 stable tetrap loids of‘Cabana’and‘Dalma’were respectively abtained.