An isolate of Cucumber mosaic virus was obtained from pepper in Guangzhou.The coat protein(CP)gene was amplified by RT-PCR using the genomic RNA as template and a pair of primers specific to CMV.Results of sequence analysis showed that the isolate was identified as an isolate of CMV，belonging to the subgroupⅠ.Forty-five pepper breeding lines was inoculated with CMV in seedling period.The results showed that 4 lines were resistant to CMV，and 20 lines were middle resistant.Five lines were selected possessing both CMV resistance and excellent agronomic characteristics.
Different rhizome lotus cultivars were attempted to identify on the basis of SSR primer pairs developed from lotus genome.Sixteen effective SSR primer pairs were screened，and six primer pairs CL1，CL2，CL4，CL9，CL14 and CL16 produced 15 polymorphic bands.The fingerprinting map was constructed and the 10 rhizome lotus cultivars could be identified by the combination and analysis of six primer pairs.The results indicated that it is feasible and effective to identify rhizome lotus cultivars by SSR markers.
The Chitinase gene was transferred into potato cultivar Desiree by protoplast PEG transformation method.The results showed that DNA at concentration of 75 μg?mL-1 led to the highest transformation efficiency.The delayed-selection method was used.The result of PCR showed that three regenerated plants were positive.
In this study，stalk waxless character was controlled by a pair of recessive nuclear genes，stalk wax is dominant，while waxless is recessive.The nuclear gene has no relation with genic male sterility gene(Ms)and fertility restoring gene(Msf).The results are concluded by crossing，backcrossing，selfing test of AB lines typeⅠ Zaoshenghuajing(with wax)and Huaguanqinggeng(waxless)，and the fertility and wax character of F1，F2 and BC1 were identified.
Grafted and own-rooted cucumbers were used to study the correlation between sensory evaluation and nutritional quality.The experiment studied the correlation between cucumber sensory evaluation and the contents of soluble sugar，soluble protein，free amino acids、dried matter，VC，titratable acid and tannin.Through correlation analysis and stepwise regression method，the results showed that sensory evaluation of own-rooted cucumber was better than that of the grafted one，the contents of soluble protein，free amino acids，VC and soluble sugar played a positive role in sensory evaluation，while tannin and titratable acid were negatively correlated with sensory evaluation.
Compared with own-rooted muskmelon Xiyu No.1 seedlings with weak hypoxia tolerance，the tolerance to hypoxia of muskmelon seedlings grafted with spong gourd and pumpkin was studied．The results showed that relative electronic conductivity，MDA content in the roots and leaves of grafted seedlings were evidently lower than that of own-rooted muskmelon seedlings under hypoxia stress.However，chlorophyll，the activity of roots，proline content and the activities of SOD，POD，CAT were evidently higher.There was a considerable difference of hypoxia tolerance between the two grafted seedlings due to the different roootstocks.The hypoxia tolerance is related to anti-oxidative ability and membrane stability in the seedlings.The results indicated that the hypoxia tolerance of muskmelon seedlings was increased through grafting with spong gourd and pumpkin.
