Water Use and Drought Response in Cultivated and Wild Apples - Abiotic Stress: Plant Responses and Applications in Agriculture - page 260

A

Histone 2 5

4.5

e d n

4

3.5

3

2.5

2

1.5

1

0.5

0

con drt

Treatment

Major Latex

B

5

e d n

4.5

4

3.5

3

2.5

2

1.5

1

0.5

0

con drt

Treatment

Figure 2. Relative expression of root genes up-regulated by drought treatment. Experiments were conducted as de‐
scribed in Methods. Test transcripts were normalized against TEF2. con: well watered controls; drt: treated to 40% sat‐
uration for two weeks. A: relative expression of Histone H2b gene; B: relative expression of the Major Latex protein
gene.

M. sieversii lines GMAL4002.e and GMAL3975.k were propagated by shoot proliferation
techniques to obtain a number of clonal individuals on their own roots. At the same time,
'Royal Gala' was propagated as a standard for comparison. Individuals from each line (4-6
trees per treatment) were acclimated under controlled conditions of light, water, fertilizer and
temperature. Water was withheld from half of each group, while the other half received
sufficient water to saturate the pot. The water-deficit trees reached 40% of pot saturation in
about 7-10 days, at which time the individual plant and a comparable control were tagged. At
the end of two weeks of treatment, the plants were individually sampled. Out of six