Table 1.
List of 36 cacao genotypes subjected to soil water deficit and their geographical origin, botanical group and gametic compatibility.
Figure 1.
Average daytime temperature and relative humidity of the air during the trial period.
Average values of 60 days ± standard error.
Table 2.
Gene specific pairs of primers used in qPCR analysis.
Table 3.
Growth and biomass characteristics of cacao genotypes subjected to two water regimes.
Figure 2.
Photographs of roots for measurement of ARS of 36 genotypes of Theobroma cacao L. subjected to soil water deficit for 60 days.
Control (○) water suppression (•). Scale: −2 cm.
Table 4.
Macro and micronutrients leaf content evaluated in 36 cacao genotypes.
Figure 3.
Activity of Guaiacol peroxidase (GPX) of T.cacao plants subjected to two watering regimes (well-watered and drought stress).
A- Tolerant; B- Moderately tolerant; C- Sensitive genotypes. Open bars represent drought stress and closed bars represent well-watered. (⊤) - mean standard error. Number of replicates (n = 8), statistical significance for the differences between well-watered and drought stress treatments is indicated as follows: * P<0.05; ** P<0.01.
Figure 4.
Activity of polyphenol oxidase (PPO) of T. cacao plants submitted to two watering regimes (well-watered and drought stress).
A- Tolerant; B- Moderately tolerant; C- Sensitive genotypes. Open bars represent drought stress and closed bars represent well-watered plants. (⊤) - mean standard error. Number of replicates (n = 8), statistical significance for the differences between well-watered and drought stress treatments is Indicated as follows: * P<0.05; ** P<0.01.
Figure 5.
Cluster analysis of 36 genotypes of Theobroma cacao L. submitted to soil water deficit for 60 days based on the Euclidean distance from the difference between control and drought for growth variables, oxidative stress (GPX and PPO) and chemical composition evaluated using the hierarchical clustering method Ward (1963).
Table 5.
Number of significant variables and distinct groups of 36 cacao genotypes subjected to water deficit in the soil for 60 days based in the 28 variables evaluated.
Figure 6.
Cluster analysis of 36 genotypes of Theobroma cacao L. submitted to soil water deficit for 60 days, based on the Euclidean distance from the difference between control and drought for the variables TLAP, RDB, SDB, LDB, TDB, RGR, and leaf contents of Ca and Mg, using the method of hierarchical clustering Ward (1963).
Figure 7.
Principal components analysis of 36 genotypes of Theobroma cacao L. subjected to soil water deficit for 60 days, based on the difference between control and drought for the variables TLAP, RDB, SDB, LDB, TDB, RGR, and leaf contents of Ca and Mg.
Table 6.
Eigenvalues and eigenvectors of the correlation matrix for the variables TLAP, RDB, SDB, LDB, TDB, RGR, and leaf contents of Ca and Mg in 36 cacao genotypes subjected to soil water deficit for 60 days.
Figure 8.
Expression of psbO (A) gene, psbA (B), NCED5 (C), and PP2C (D) in plant leaves of 6 genotypes of Theobroma cacao L. subjected to soil water deficit for 60 days.
2-ΔΔCt method. β-tubulin gene as a reference.