Sensitivity of Yield and Fruit Quality of French Prune to Water Deprivation at Different Fruit Growth Stages

Abstract

<jats:p>The sensitivity of French prune <jats:italic>(Prunus domestica</jats:italic> L. syn. `Petite d'Agen') to water deprivation at various fruit growth stages was studied over 3 years in a drip-irrigated orchard. The soil was a poorly drained Rocklin fine sandy loam with a hardpan that varied from 4.75 to I m from the surface at the northern end of the orchard (shallow soil condition) to no hardpan apparent to 2 m below the surface at the southern end of the orchard (deep soil condition). Water deprivation during a) the first exponential phase of fruit growth or stage I, b) lag phase of fruit growth or stage II, c) first half of stage II, d) second half of stage II, e) second exponential fruit growth phase or stage III, and f) postharvest was compared to a fully watered control. Water deprivation caused the most severe reduction in tree water status when it was imposed over longer periods of time and during periods of high evaporative demand and also had mm-e severe effects under shallow soil conditions. Compared to the control treatment, deprivation during all of stage II (the most severe deprivation treatment) was associated with increased Ilowering, reduced fruit hydration ratio, and smaller fruit size under all soil conditions. Under deep soil conditions, deprivation during all of stage II resulted in increased return bloom, which was reflected in higher fruit loads and dry t-ha-' fruit yield. However, under shallow soil conditions, even though return bloom was increased with this treatment, fruit loads and dry t·ha<jats:sup>-1</jats:sup> fruit yields were the lowest of all treatments. These differences in treatment effects in shallow vs. deep soil conditions were most likely the result of increased fruit drop, which occurred under shallow soil conditions as a result of rapid onset and increased severity ofstress. Treatments that had parallel effects in shallow and deep soil conditions resulted in statistically significant overall treatment effects, while those that had opposing effects in shallow vs. deep soil conditions did not show significant overall treatment effects. Substantial alternate hearing occurred, and, in general, dry fruit yields above ≈9 dry t·ha<jats:sup>-1</jats:sup> resulted in a decrease in fruit load the following year, while loads below this value showed a subsequent increase. Based on a separate estimate of the theoretically stable value for each treatment, all deprivation treatments resulted in a higher sustainable fruit load compared to the fully irrigated control. This suggests that, for the purpose of prune fruit production, there may be an optimal level of tree water stress.</jats:p>

Identifying irrigation zones across a 7.5-ha ‘Pinot noir’ vineyard based on the variability of vine water status and multispectral images

“…We think this higher variability was due to water stress in vines growing in zones with shallower soils. This is similar to what Lampinen et al (1995) found when comparing different soil types under RDI. Maximum yield in 2009 was higher than those in (Table 1).…”

Influence of Irrigation Method and Scheduling on Patterns of Soil and Tree Water Status and Its Relation to Yield and Fruit Quality in Peach

“…However, even when irrigation intervals were shortened to every 3 d, almond trees irrigated by microsprays had lower water potentials during periods of peak water demand than those irrigated daily by drip (Edstrom and Schwankl, 2004). Since water potential is well correlated to production and fruit size in tree fruit (Naor, 2001;Naor et al, 1995Naor et al, , 1999, lower water potentials between irrigations may be most critical in midseason varieties that ripen during summer months, especially in trees with heavy crop loads during Stage III of fruit development (Lampinen et al, 1995, Marsal et al, 2005Naor et al, 2001). The cultivar used in the present study was an early-season variety that ripened in late May to early June.…”

Long-term Effects of Restricted Root Volume and Regulated Deficit Irrigation on Peach: I. Growth and Mineral Nutrition

“…RDI has been adopted extensively to control vegetative growth of deciduous trees (Boland et al, 1993;Caspari et al, 1994;Chalmers et al, 1986;Fereres and Goldhamer, 1990;Lampinen et al, 1995;Mitchell et al, 1989). In contrast to the significant effect of soil volume, RDI had minimal influence on tree growth in the current experiment (Tables 4, 5 and 6).…”