Heritability and genetic variation of plant biomass, transpiration, and water use efficiency for an apple core-collection

Abstract

To study the heritability and genetic variation of plant biomass, transpiration and water use efficiency (WUE) in apple (Malus × domestica Borkh.), 193 genotypes from an INRA apple core-collection were evaluated in 2014. Four grafted replicates per genotype grown as one-year-old scions were studied in a high-throughput phenotyping platform (PhenoArch). Individual pot weight was recorded twice a day and irrigation was scheduled to maintain constant soil water content (SWC) and avoid any water stress during 46 days. Plant 3D pictures were automatically taken every two days. Analysis of pictures and pot weights differences allowed the estimation of whole-plant biomass and transpiration during the experiment. WUE was calculated as the ratio of accumulated biomass to transpiration. For each trait, we tested nine mixed models to account for the genetic effect and spatial variability inside PhenoArch. The Best Linear Unbiased Predictors (BLUPs) of genetic values were estimated after model selection. For each trait, broad-sense heritability (H 2) was calculated from variance estimates. Plant biomass, transpiration and WUE had H 2 values of 0.76, 0.54, and 0.73, respectively. The H 2 value of WUE is high enough to consider that this trait is under genetic control in apple. The genetic variation of WUE indicated that apple genetic resources such as the INRA core-collection could be extremely useful to improve apple plant material for the use of water.

Investigation of stem anatomy in relation to hydraulic conductance, vegetative growth and yielding potential of ‘Summit’ cherry trees grafted on different rootstock candidates

“…Since investigated stems were of the same age, sampled from the same part of the plant and grown in the same environmental setting, SDs are presumed to be strongly genetically dependent as previously noted for eucalyptus (Bartholomé et al, 2020). High heritability and genetic control of anatomical traits and water use efficiency was previously noted by Lauri et al (2011) as well as Lopez et al (2017). Lesser variation in CSA was observed in scion stems in comparison with the rootstock stems, indicating that to some extent scion retains its scionspecific cambial activity.…”