Diurnal root growth dynamics in mature grapevines

Abstract

Six-year-old Shiraz vines were grown under field-like conditions in 780 L soil filled plastic bins. One year after transplanting, root growth was monitored non-destructively using minirhizotron tubes. Images of the roots were collected at sunrise, midday, sunset and midnight over six consecutive days during flowering. It was found that the vines displayed a diurnal dynamic in root growth with a maximum in the afternoon and evening, and a minimum in the morning. While it was not possible to separate the effects of time of day and soil temperature a positive relationship between soil temperature and root elongation was observed. The diurnal dynamics of root growth was consistent with earlier observations in young potted vines, and is the first indication that mature vines also exhibit a pronounced diurnal dynamic of fine root growth. The possible influence of carbon supply and the role of the circadian clock in these diurnal growth dynamics are discussed.

Yield and must composition of grapevines subjected to phosphate fertilization in Southern Brazil

“…al., 2016), leaf P concentrations were interpreted as adequate. This supports the hypothesis that grapevines have mechanisms that increase P uptake efficiency, such as the increased growth of the root system into deeper soil layers (Mahmud et al, 2018), root association with arbuscular mycorrhizal fungi (Schreiner, 2005), and accumulation of internal reserves of P in perennial organs (Pradubsuk & Davenport, 2010;Gautier et al, 2018). As for the chemical composition of the must, differences in total soluble solids (TSS), total titratable acidity, pH, and tartaric acid were observed between crop seasons for both cultivars (Tables 3 and 4).…”