Effects of Drought and Rewater on the Growth Indicators of Seedlings in Different Wheat Varieties (Lines)

Purpose To clarify the effects of drought and rewater treatment on the growth indicators of different wheat varieties.

Methods The drought-resistant variety Jingmai 12 and the drought-sensitive variety Yun 0073 were used as materials in this experiment. When the wheat was grown to the three-leaf stage, the seedlings were taken by drought stress and rewater method to investigate the plant height, shoot dry weight, root dry weight, root-shoot ratio, number of primary roots, root length, root mean diameter and root volume, root surface area, with normal water management as a control.

Results Analysis of variance showed that the significant differences in dry weight of underground part, ratio of root to shoot, total root length, average root diameter and total root volume between the two varieties (lines) under drought (P<0.01), and significant differences in plant height, dry weight of aboveground part and total root surface area (P<0.05). Under drought stress, the growth indicators of Yun 0073 seedlings were significantly lower than the control except for the number of primary roots (P<0.05), but there was no significant change in all the indicators of Jingmai 12 (P>0.05). The change trends of the primary roots number between two varieties were basically the same under rewater conditions, but all other morphological indicators of Jingmai 12 were significantly better than Yun 0073 (P<0.05). Under the treatment of drought and rewater, there was a extremely significant negative correlation between varieties and plant height (P<0.01), and a significant negative correlation between varieties and average root diameter (P<0.05), the dry weight of underground part was extremely positively correlated with average root diameter and total root volume (P<0.01), and positively correlated with aboveground part and total root surface area (P<0.05), the dry weight of the underground part was extremely positively correlated with the total root volume and the total surface area of the root (P<0.01), and extremely positively correlated with the total root length (P<0.01), the total root length was extremely positively correlated with the total surface area of the root (P<0.01), and positively correlated with the average diameter and the total volume of the root (P<0.05), the average root diameter was positively correlated with the total root surface area (P<0.05), and the total root volume was extremely positively correlated with the total root surface area (P<0.01).

Conclusion The response of different drought resistant varieties to drought was different, and many indexes of Jingmai 12 were obviously better than those of Yun 0073, which was sensitive to drought. The effect of drought was relatively small, and the growth indexes were better. Jingmai 12 could recover quickly after rewater, while Yun 0073 was rewater after five days. There was a negative correlation between a small number of growth indicators and a positive correlation between most indicators under drought and rewater. Compared with Yun 0073, Jingmai 12 shows a stronger ability to resist drought and recover water.