Abscysic acid and compatibility of atemoya (Annona x atemoya Mabb.) grafted onto native species

Abstract

Grafting is an effective technique used in the cultivation of commercial fruit species given the necessity to guarantee the genetic characteristics of productive species using selected clones. Although grafting is a common and widespread technique and phytohormones play a key role in the formation of tissues, the relationship between phytohormones, such as abscisic acid, and mechanisms of incompatibility is not yet well elucidated. Thus, the objective of this study was to establish whether a correlation exists between variations in abscisic acid and the compatibility of the atemoya (Annona x atemoya Mabb.) cultivar ‘Thompson’ grafted onto biribá [Annona mucosa (Bail.) H. Rainer], araticum-mirim [Annona emarginata (Schltdl.) H. Rainer ‘var. mirim’] and araticum-de-terra-fria [Annona emarginata (Schltdl.) H. Rainer ‘var. terra-fria’]. Plant cultivation was carried out at the Botany Department of Instituto de Biociências (IB), Unesp, Botucatu, São Paulo, Brazil. The plant material of grafted plants (stem above the grafted area, stem containing the grafted region, and stem below the grafted region) and ungrafted plants (stem 20 cm above ground) was collected 500 days after grafting (DAG) for the extraction and quantification of abscisic acid. The results of this study show that ungrafted Annona plants exhibit variations in the concentration of abscisic acid among the native rootstock species. When grafted, the most commonly used grafting combinations, araticum-de-terra-fria and araticum-mirim, present the same concentrations of abscisic acid in the graft region as self-grafted atemoya. It was concluded that the observed variations in the concentrations of abscisic acid in the graft region did not cause incompatibility in the combinations of atemoya grafted onto different native species.

Salicylic Acid Increases Growth of Schinus terebinthifolia Seedlings Subjected to Varyng Irrigation Intervals

“…Under the prolongation of the plants to water stress, the lowest water availability due to the longest irrigation interval (12-day interval), there was leaf abscission. Leaf fall by senescence was stimulated owing to a decrease in levels of auxin and increase in levels of ABA in the leaf tissue (Baron et al, 2018). This response is considered a strategy to reduce the transpiration rate and maximize the optimization of water use for metabolic processes.…”

“…The prolongation of limited water availability in the soil by lower irrigation frequency may have a negative effect on metabolic processes, as it reduces the capacity for CO 2 assimilation owing to the closure of stomata, reduction of mesophyll conductance (Matos et al, 2018), and lowered carboxylation of ribulose 1.5 bisphosphate carboxylase/ oxygenase (RUBISCO) (Yang et al, 2014), and increase of reactive oxygen species (ROS). Under these conditions, leaf fall triggered by senescence increases owing to a reduction in auxin concentration and an increase in abscisic acid (ABA) concentration, which increases the levels of ethylene in the leaf tissue (Baron et al, 2018). Thus, management of water in the substrate is a determining factor in the initial growth, making it necessary to associate products that may mitigate the negative effects of lower irrigation frequency in the seedlings.…”

Potential Potential of a native araticum species as the rootstock of atemoya cultivars propagated by grafting methods

“…Studies with native species of the family Annonaceae, such as Annona glabra, A. mucosa, A. reticulata, A. sylvatica, and A. emarginata, have shown their potential to be used as rootstock (Almeida et al, 2010;Leite et al, 2013;Silva et al, 2016;Baron, Gimenez, & Ferreira, 2018), moreover, few studies have been using different atemoya cultivars as a scion for these native species. The araticum [Annona sylvatica (A.…”