Article Figures & Data
Figures
- Fig. 1.
Southern analysis of genomic DNA from R1 and S1 sunflower genotypes. Total DNA was digested with EcoRI (E) and HindIII (H), separated on an agarose gel, and transferred to a nylon membrane. A, Membranes were probed with32P-labeled cDNA as indicated. B, Membrane was probed with the 3′ noncoding region of HaElip1 cDNA (nucleotides 559 to 795 of HaElip1 cDNA full-length sequence).
- Fig. 2.
Soil and leaf water status of R1 (•) and S1 (□) plants during progressive drought initiated by withholding water. A, Predawn leaf water potential as a function of gravimetric soil water content (grams of water per gram of dry soil). B, Leaf water potential as a function of gravimetric soil water content (grams of water per gram of dry soil). Leaf water potential and gravimetric soil water content values are the means ± se of four to six measurements determined from four to six individual plants.
- Fig. 3.
Accumulation of HaDhn1,HaDhn2, and HaElip1 transcripts in leaves of R1 and S1 plants subjected to progressive drought as a function of gravimetric soil water content (grams of water per gram of dry soil). Total RNA was purified from R1 (•) or S1 (□) individual leaves collected as indicated from all of the plants described in Figure 2B. RNA (10 μg) was analyzed by northern-blot hybridization usingHaDhn1, HaDhn2, andHaElip1/3′ end as probes. Hybridization signals were quantified by densitometric analysis. The strongest hybridization signal was set at 10 and the others were quantified on the basis of this signal. The relative mRNA levels are the means ± se of four to six measurements quantified separately from individual plants. Gravimetric soil water content values are the means of measurements determined on the corresponding plants described in Figure 2B.
- Fig. 4.
Accumulation of HaDhn1,HaDhn2, and HaElip1 transcripts as a function of leaf water potential in R1 and S1 plants subjected to progressive drought. Total RNA was purified from R1 (black bars) or S1 (white bars) individual leaves collected separately from the plants described in Figure 2B. RNA (10 μg) was analyzed by northern-blot hybridization using HaDhn1, HaDhn2, andHaElip1/3′ end as probes. Hybridization signals were quantified by densitometric analysis. The strongest hybridization signal was set at 10 and the others were quantified on the basis of this signal. The relative mRNA levels are the means ± se of 6 to 10 measurements quantified separately from individual plants.
- Fig. 5.
Concentration of ABA in R1 (•) and S1 (□) xylem sap as a function of soil water content (grams of water per gram of dry soil). Each point represents a coupled value of xylem ABA of one leaf and the soil water content of the corresponding plant. Data are the result of one representative experiment.
- Fig. 6.
Stomatal conductance of R1 (A) and S1 (B) in response to ABA. Plants were grown in hydroponic conditions supplemented (•, ▪) or not (○, □) with 10 μm ABA. The addition of ABA was performed at 6 am (solar time). Stomatal conductance was determined from 8 am to the end-of-the-day period on control and ABA-treated R1 and S1 plants. Each point is the mean value of two opposite leaves from the same plant. The bar at the top indicates the light/dark period under which the plants were grown (white bar, light period; black bar, dark period). Hours refer to the solar time at which the measurements were determined.
- Fig. 7.
Time course of accumulation ofHaDhn1 and HaDhn2 transcripts in response to ABA in leaves of tolerant (black bars) and sensitive (white bars) plants. Total RNA was purified from leaves of R1 and S1 sunflowers cultivated in hydroponic medium supplemented or not with 10 μm of ABA. RNA (10 μg) extracted from plants 6, 12, 28, and 48 h after the addition of ABA or from control plants (lane C) was analyzed by northern-blot hybridization with the indicated probes. Hybridization signals were quantified by densitometric analysis. The strongest hybridization signal was set at 10 and the others were quantified on the basis of this signal. Values are means ± se of three to four independent replicates. The bars at the top indicate the light/dark period under which the plants were grown (white bar, light period; black bar, dark period). Hours refer to the solar time at which the samples were collected.
