Performance of grain yield, biochemical and anatomical characters under water stress conditions in some bread wheat genotypes

Abstract EN

A field experiment was carried out during 2013/2014 and 2014/2015 winter growing seasons at the Experimental Farm, Kafr El-Hamam Agricultural Research Station, Zagazig, Sharkia Governorate, Egypt, to evaluate 20 wheat genotypes and cultivars under three irrigation regimes.

Plants in the first regime were irrigated four times after planting irrigation (normal irrigation I1).

In the second regime plants were irrigated two times after planting irrigation (I2).

In the third regime plants were given one surface-irrigation 25 days after planting irrigation (I3).

A wide border (7m) was made to minimize the underground water permeability surrounded each experiment.

The experiment was laid out in a split-plot design with three replications.

Highly significant genotype differences were registered for grain yield and its components in both seasons and combined.

The interactions between genotypes and water regime treatments for grain yield and its components were highly significant for all characters in both seasons and combined except for 1000 grain weight in first season.

The obtained results showed that I1 treatment gave the highest water consumptive use and applied irrigation water.

Results indicated that values of water consumptive use in the first season were 520.1, 382.6 and 275.3 mm for irrigation regimes I1, I2 and I3, respectively.

However, in the second season the corresponding values of the water consumptive use were 494.7, 370.9 and 263.4 mm, respectively.

Genotype No.

2 gave the least value of water consumptive use, while genotype No.

13 recorded the highest water consumptive use.

Water utilization efficiency (kg grains/ m3 applied water) revealed that I3 gave the highest value, whereas I1was the lowest one.

The highest water utilization efficiency was registered by Genotype 8, while genotype 3 recorded the lowest value for this measurement.

Drought sensitivity index (DSI) reveal that genotypes No 1, 5, 8, 10, 12, 16 and 18 were tolerant to water stress.

Moderate drought stress resulted in significant increase in total soluble sugars, proline and free amino acids in the studied genotypes.

Under sever stress, the above mentioned characters significantly increased in genotypes No 1, 2 and 3 compared to other tested genotypes.

Therefore wheat genotypes No.1, 2 and 3 could be classified as more tolerant to moderate drought stress.

Anatomical features of 5 wheat genotypes were influenced by drought stress.

It has been noticed that genotype No.

20 recorded the highest reduction in anatomical characters.

On the other hand, the least reduction was detected in genotype No.

1 compared to other tested genotypes.

Genotype No.

1 appeared to be more tolerant to drought stress as it exhibited DSI less than unity and gave increase in total soluble sugars, proline and free amino acids with lowest reduction in leaf anatomical characteristics.

The study recommend genotype No.

1 as more tolerant to drought stress with good level of yield productivity.