extremely significantP < 0.01
It can be seen from Table 2 that, among those three factors affecting plant height increment, the main effect of different ‘salt stress degrees’ was extremely significant ( P < 0.01), while the main effect of ‘varieties’ and ‘spraying GABA or not’ was least significant ( P > 0.05), with which the P value of ‘spraying GABA or not’ was 0.055.