Postharvest performance of ‘Hass’ avocado fruit is influenced by rootstock

Abstract

Clonal avocado (Persea americana Mill.) rootstocks maintain the desirable characteristics of the rootstock which confer the tree a better performance under adverse growing conditions. Rootstocks influence the internal quality of avocado fruit as they can have different abilities to absorb and transport nutrients and organic compounds to tree’s canopy. However, this behavior depends on the rootstock-cultivar interaction. The objective of this research was to evaluate the influence of 10 drought and five Phytophthora cinnamomi tolerant rootstocks on the postharvest quality of ‘Hass’ avocado fruit. 'Hass' fruit were harvested from rootstocks tolerant to drought (rainfed orchard, annual rainfall 1300 mm) and P. cinnamomi (monthly irrigation relief from April to June). In each case, 'Hass' fruit from Creole (native) rootstocks originated by seed were included. Different groups of fruit were stored at room temperature (25 oC ± 1 oC and 60% RH) or cooled for 14 and 28 days (5 oC ± 1 oC and 90% RH). Starting at harvest and during storage pulp dry matter (CMS) and oil content (CA), as well as fruit firmness (F) and physiological weight loss (PFP) were measured until eating maturity. Evaluation of drought tolerant rootstocks showed: i) At the time of harvest, the different rootstocks affected pulp CMS and CA, ii) Type of rootstock inf luenced pulp CMS and CA, as well as PFP in fruit stored either at room temperature or refrigerated during 14 or 28 days. F was the less affected parameter. The study with P. cinnamomi tolerant rootstocks showed no effect of rootstock on fruit quality at harvest or during storage.