Vegetative and Reproductive Traits of Two Southern Highbush Blueberry Cultivars Grafted onto Vaccinium arboreum Rootstocks

Abstract

<jats:p><jats:italic>Vaccinium arboreum</jats:italic> Marsh is a wild species adapted to high pH (above 6.0) and low organic matter soils (below 2.0%). The use of <jats:italic>V. arboreum</jats:italic> rootstocks may be a viable option to increase soil adaptation of southern highbush blueberry (SHB) (<jats:italic>Vaccinium corymbosum</jats:italic> interspecific hybrid) under marginal soil conditions. The objective of this research was to evaluate the vegetative and reproductive traits of ‘Farthing’ and ‘Meadowlark’ SHB own-rooted or grafted onto <jats:italic>V. arboreum</jats:italic> and grown in pine bark–amended or nonamended soil. The study was conducted from 2012 through 2014 at a research center in Citra, FL, and a grower’s farm in Archer, FL. <jats:italic>Vaccinium arboreum</jats:italic> rootstock generally induced the same effects in both cultivars. Grafted plants in both soil treatments had reduced canopy growth in the first year after field planting compared with own-rooted plants in amended soil. However, canopy volume of grafted plants was greater than own-rooted plants in nonamended soil and similar to own-rooted plants in amended soil 2 years after field planting for ‘Meadowlark’ and 3 years after planting for ‘Farthing’. Fruit yield was lower in grafted plants compared with own-rooted plants in the first fruiting year (2 years after field planting). By the second fruiting year, yields of grafted plants were similar to or greater than yields of own-rooted plants when grown in nonamended soil, whereas in amended soil, yields of grafted plants were similar to yields of own-rooted plants. Grafted plants had greater mean berry weight, but lower berry firmness; however, the firmness values were still considered acceptable (greater than 160 g⋅mm<jats:sup>−1</jats:sup>). Internal fruit quality [total soluble solids (TSS) and total titratable acidity (TTA)] was not consistently affected by the rootstock or soil treatments. These results suggest that grafting SHB onto <jats:italic>V. arboreum</jats:italic> does not increase yield in the establishment years compared with own-rooted SHB when grown in amended soils, but may have the ability to increase yield with no negative effects on fruit quality when grown in nonamended soils.</jats:p>

Regulation of gene expression in roots of the pH-sensitive Vaccinium corymbosum and the pH-tolerant Vaccinium arboreum in response to near neutral pH stress using RNA-Seq

“…These results, combined with the lack of rhizosphere acidification reported in VA [ 12 ], suggests that VA exhibits tolerance –rather than avoidance– to growth at higher soil pH. These findings resonate with field-trials where VC grafted onto VA rootstocks outperformed own-rooted VC in unamended soils [ 10 ]. To understand the mechanisms underlying the tolerance to pH in VA, several genes that showed DE in VA but not in VC will be discussed.…”

“…Additionally, VA exhibits greater ability to take up nitrate –the most abundant form of nitrogen at higher pH– and iron –an element with reduced solubility at higher pH– than VC [ 9 ]. This has motivated the use of VA as a rootstock for blueberry production [ 10 ] and a genetic source for blueberry breeding [ 11 ]. Yet, few aspects of the soil adaptation of VA have been studied to date.…”

VcFT-induced mobile florigenic signals in transgenic and transgrafted blueberries

“…Grafting is not a common practice for blueberry bushes, but it has potential to increase abiotic stress tolerance for cultivated blueberry cultivars 48 . In this study, the survival rate of grafted scions on T rootstocks ranged from 16.7 to 60.0% 2 weeks after grafting.…”

Mechanical Harvesting and Postharvest Storage of Two Southern Highbush Blueberry Cultivars Grafted onto Vaccinium arboreum Rootstocks

“…Four scion/rootstock combinations were tested: 1) own-rooted 'Farthing', 2) 'Farthing' grafted onto V. arboreum, 3) ownrooted 'Meadowlark', and 4) 'Meadowlark' grafted onto V. arboreum. Scions and rootstocks were propagated as previously described by Casamali et al (2016). Briefly, own-rooted plants were propagated by stem cuttings at a commercial nursery in Summer 2010.…”