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ABA-mediated responses to water deficit separate grapevine genotypes by their genetic background.

Rossdeutsch L, Edwards E, Cookson SJ, Barrieu F, Gambetta GA, Delrot S, Ollat N - BMC Plant Biol. (2016)

Bottom Line: The transcript abundance of 12 genes involved in ABA biosynthesis, catabolism, and signalling were monitored, together with physiological and metabolic parameters related to ABA and its role in controlling plant transpiration.In contrast, the ABA RCAR receptors were not identified as key components of the genotypic variability of water-deficit responses.In addition, it supports that adaptation may be related to various mechanisms related or not to ABA responses.

View Article: PubMed Central - PubMed

Affiliation: UMR EGFV, ISVV-INRA, 210 chemin de Leysotte, 33882, Villenave d'Ornon, France.

ABSTRACT

Background: ABA-mediated processes are involved in plant responses to water deficit, especially the control of stomatal opening. However in grapevine it is not known if these processes participate in the phenotypic variation in drought adaptation existing between genotypes. To elucidate this question, the response to short-term water-deficit was analysed in roots and shoots of nine Vitis genotypes differing in their drought adaptation in the field. The transcript abundance of 12 genes involved in ABA biosynthesis, catabolism, and signalling were monitored, together with physiological and metabolic parameters related to ABA and its role in controlling plant transpiration.

Results: Although transpiration and ABA responses were well-conserved among the genotypes, multifactorial analyses separated Vitis vinifera varieties and V. berlandieri x V. rupestris hybrids (all considered drought tolerant) from the other genotypes studied. Generally, V. vinifera varieties, followed by V. berlandieri x V. rupestris hybrids, displayed more pronounced responses to water-deficit in comparison to the other genotypes. However, changes in transcript abundance in roots were more pronounced for Vitis hybrids than V. vinifera genotypes. Changes in the expression of the cornerstone ABA biosynthetic gene VviNCED1, and the ABA transcriptional regulator VviABF1, were associated with the response of V. vinifera genotypes, while changes in VviNCED2 abundance were associated with the response of other Vitis genotypes. In contrast, the ABA RCAR receptors were not identified as key components of the genotypic variability of water-deficit responses. Interestingly, the expression of VviSnRK2.6 (an AtOST1 ortholog) was constitutively lower in roots and leaves of V. vinifera genotypes and higher in roots of V. berlandieri x V. rupestris hybrids.

Conclusions: This study highlights that Vitis genotypes exhibiting different levels of drought adaptation differ in key steps involved in ABA metabolism and signalling; both under well-watered conditions and in response to water-deficit. In addition, it supports that adaptation may be related to various mechanisms related or not to ABA responses.

No MeSH data available.


Related in: MedlinePlus

Principal component analysis of physiological and transcript abundance data. Plots for variable contribution to each principal component (a) and projection of individual observations (b) on PC1 and PC2. For A, mean of expression of each gene is presented in leaves (L) and root tips (R) and mean of abscisic acid (ABA), phaseic acid (PA) and dihydroxyphaseic acid (DPA) is presented in shoot (S) and root (R) xylem sap. For B, key to symbols as shown in Fig. 1c, numbers indicate the number of days of withheld irrigation
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Fig7: Principal component analysis of physiological and transcript abundance data. Plots for variable contribution to each principal component (a) and projection of individual observations (b) on PC1 and PC2. For A, mean of expression of each gene is presented in leaves (L) and root tips (R) and mean of abscisic acid (ABA), phaseic acid (PA) and dihydroxyphaseic acid (DPA) is presented in shoot (S) and root (R) xylem sap. For B, key to symbols as shown in Fig. 1c, numbers indicate the number of days of withheld irrigation

Mentions: Finally, a principle component analysis was done on the average of all raw data per genotype and day of sampling. The first two components, PC1 and PC2, explained 63 % of total variability (Fig. 7). The abundance of transcripts of most genes, as well as all physiological variables, were highly correlated to PC1, except for VviSnRK2.6 and VviNCED2 in the leaves, which were highly correlated to PC2 (Fig. 7a). [ABA], [PA] and [DPA] cluster tightly with the expression of VviNCED1 in both tissues, and with VviABF1, VviABF2 and VviPP2C4 in the leaves (Fig. 7a, Additional file 8). The score plot of individual observations on the plan defined by the first two main components shows that PC1 and PC2 are mainly described by the water status and genotype effects respectively. Under water-stress, all genotypes shifted towards the positive side of PC1 with 140Ru, 110R and 41B located in an intermediate position along PC1, between Syrah and Grenache and the other genotypes studied. Some variability can also be observed between genotypes along PC1 for their response at 3 days of withheld irrigation. In addition water-stressed Syrah and Grenache (Fig. 7b) remained on the negative part of PC2 while the other genotypes moved to the positive part of this component.Fig. 7


ABA-mediated responses to water deficit separate grapevine genotypes by their genetic background.

Rossdeutsch L, Edwards E, Cookson SJ, Barrieu F, Gambetta GA, Delrot S, Ollat N - BMC Plant Biol. (2016)

Principal component analysis of physiological and transcript abundance data. Plots for variable contribution to each principal component (a) and projection of individual observations (b) on PC1 and PC2. For A, mean of expression of each gene is presented in leaves (L) and root tips (R) and mean of abscisic acid (ABA), phaseic acid (PA) and dihydroxyphaseic acid (DPA) is presented in shoot (S) and root (R) xylem sap. For B, key to symbols as shown in Fig. 1c, numbers indicate the number of days of withheld irrigation
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4836075&req=5

Fig7: Principal component analysis of physiological and transcript abundance data. Plots for variable contribution to each principal component (a) and projection of individual observations (b) on PC1 and PC2. For A, mean of expression of each gene is presented in leaves (L) and root tips (R) and mean of abscisic acid (ABA), phaseic acid (PA) and dihydroxyphaseic acid (DPA) is presented in shoot (S) and root (R) xylem sap. For B, key to symbols as shown in Fig. 1c, numbers indicate the number of days of withheld irrigation
Mentions: Finally, a principle component analysis was done on the average of all raw data per genotype and day of sampling. The first two components, PC1 and PC2, explained 63 % of total variability (Fig. 7). The abundance of transcripts of most genes, as well as all physiological variables, were highly correlated to PC1, except for VviSnRK2.6 and VviNCED2 in the leaves, which were highly correlated to PC2 (Fig. 7a). [ABA], [PA] and [DPA] cluster tightly with the expression of VviNCED1 in both tissues, and with VviABF1, VviABF2 and VviPP2C4 in the leaves (Fig. 7a, Additional file 8). The score plot of individual observations on the plan defined by the first two main components shows that PC1 and PC2 are mainly described by the water status and genotype effects respectively. Under water-stress, all genotypes shifted towards the positive side of PC1 with 140Ru, 110R and 41B located in an intermediate position along PC1, between Syrah and Grenache and the other genotypes studied. Some variability can also be observed between genotypes along PC1 for their response at 3 days of withheld irrigation. In addition water-stressed Syrah and Grenache (Fig. 7b) remained on the negative part of PC2 while the other genotypes moved to the positive part of this component.Fig. 7

Bottom Line: The transcript abundance of 12 genes involved in ABA biosynthesis, catabolism, and signalling were monitored, together with physiological and metabolic parameters related to ABA and its role in controlling plant transpiration.In contrast, the ABA RCAR receptors were not identified as key components of the genotypic variability of water-deficit responses.In addition, it supports that adaptation may be related to various mechanisms related or not to ABA responses.

View Article: PubMed Central - PubMed

Affiliation: UMR EGFV, ISVV-INRA, 210 chemin de Leysotte, 33882, Villenave d'Ornon, France.

ABSTRACT

Background: ABA-mediated processes are involved in plant responses to water deficit, especially the control of stomatal opening. However in grapevine it is not known if these processes participate in the phenotypic variation in drought adaptation existing between genotypes. To elucidate this question, the response to short-term water-deficit was analysed in roots and shoots of nine Vitis genotypes differing in their drought adaptation in the field. The transcript abundance of 12 genes involved in ABA biosynthesis, catabolism, and signalling were monitored, together with physiological and metabolic parameters related to ABA and its role in controlling plant transpiration.

Results: Although transpiration and ABA responses were well-conserved among the genotypes, multifactorial analyses separated Vitis vinifera varieties and V. berlandieri x V. rupestris hybrids (all considered drought tolerant) from the other genotypes studied. Generally, V. vinifera varieties, followed by V. berlandieri x V. rupestris hybrids, displayed more pronounced responses to water-deficit in comparison to the other genotypes. However, changes in transcript abundance in roots were more pronounced for Vitis hybrids than V. vinifera genotypes. Changes in the expression of the cornerstone ABA biosynthetic gene VviNCED1, and the ABA transcriptional regulator VviABF1, were associated with the response of V. vinifera genotypes, while changes in VviNCED2 abundance were associated with the response of other Vitis genotypes. In contrast, the ABA RCAR receptors were not identified as key components of the genotypic variability of water-deficit responses. Interestingly, the expression of VviSnRK2.6 (an AtOST1 ortholog) was constitutively lower in roots and leaves of V. vinifera genotypes and higher in roots of V. berlandieri x V. rupestris hybrids.

Conclusions: This study highlights that Vitis genotypes exhibiting different levels of drought adaptation differ in key steps involved in ABA metabolism and signalling; both under well-watered conditions and in response to water-deficit. In addition, it supports that adaptation may be related to various mechanisms related or not to ABA responses.

No MeSH data available.


Related in: MedlinePlus