[Salt resistance of different tomato genotypes at seed germination stage]

Based on the cluster analysis of relative germination potential and relative germination rate under NaCl stress, fourteen tomato genotypes were clustered into two groups. Five tomato genotypes held high resistance to NaCl stress, and nine tomato genotypes were moderately NaCl- tolerant. The highly NaCl- tolerant genotypes wild Lycopersicon pimpinellifolium, Liaoyuanhongmanao and Hongbaoshi and the moderately NaCl- tolerant genotype Liaoyuanhongduoli were then under different Na(+)-salts and NaCl, Na+, and Cl- stresses. The responses of the four tomato genotypes to different Na(+)-salts stress were the same as those to NaCl stress. Among the test Na(+)-salts, NaHCO3 had the greatest impact. Under the stress of 100 mmol NaHCO3 x L(-1), the embryo's relative lengths of the four tomato genotypes were all below 8%. The inhibitory effect of test Na(+)-salts on tomato seed germination was in the order of NaNO3 < Na2SO4 < NaH2PO4 < NaCl < NaHCO3. As for NaCl, Na+ and Cl-, the Cl- had the smallest injury.