In this section:
Abstracts
Distribution of grapevine roots and soil salt under drip and full-cover microjet irrigation systems
Stevens, R.M., and Douglas, T. (1994). Irrigation Science 15:147–52.
Summary
We describe the three dimensional variation in Lv within a quarter of the planting area of Colombard grapevines on Ramsey rootstock grown under drip and full-cover microjet irrigation. Under drip irrigation roots were concentrated under the vine row, whereas under microjet irrigation roots were evenly spread across the planting area. The maximum Lv were 1.2 and 0.6 cm/cm3 and the estimated total root lengths per vine were 32 and 26 km for drip and microjet irrigated vines, respectively. Under drip, 56% of the variation in Lv could be accounted for as a function of depth and radial distance into the row, and under microjet, 45% of the variation in Lv could be accounted for as a function of depth. Twenty five per cent of the vine roots were in soil with an air filled porosity at field capacity of 6% or less. Based on the variation of root length per unit area (La) across a quarter of the planting area and between vines, we concluded that selection of a location at which the La would be representative of that in the entire irrigation unit is feasible in microjet irrigated vines but not in those irrigated with drip. We suggest that the absence of a location representative of La confounds the scheduling of drip irrigation based solely on measurements of soil moisture.
The effect of transient waterlogging on the growth, leaf gas exchange, and mineral composition of potted Sultana grapevines
Stevens, R.M. and Prior, L.D. (1994). American Journal of Enology and Viticulture 45:285–290.
Abstract
Potted Sultana vines were waterlogged for the first 0, 1, 3, 5 or 7 days of a two week cycle designated W0, W1, W3, W5, and W7, respectively. The vines were harvested at the end of the fourth cycle. Shoot elongation rates over the first two cycles for W0 to W7 were 56, 51, 34, 38 and 35 mm/day, respectively. Vine leaf and stem dry weights at harvest were 37, 32, 22, 21, and 19 g/vine for W0 to W7, respectively. Photosynthesis and stomatal conductance were reduced both during and following waterlogging but leaf water potential was unaffected. Waterlogging reduced leaf blade N, P and Ca, increased Na and Mg, and did not affect K, Cl, Mn, Zn and N-NO3.
Soil water depletion rates under large grapevines
Stevens, R.M., and Harvey, G. (1996). Australian Journal of Grape and Wine Research 2:155–162.
Abstract
Over two consecutive seasons, daily rates of change in the water content of the top 120 cm of soil were calculated for sample sites located at 50 cm from the butts of 12 Colombard vines on Ramsey rootstock which were part of a controlled deficit irrigation experiment. Records were selected where the rate represented a change due solely to depletion of soil water by grapevine evapotranspiration (DSET). Soil water availability was quantified as a logarithmic transformation of the absolute value of the root-weighted measure of soil matric potential. DSET was negatively correlated with soil water availability and positively correlated with reference crop evapotranspiration (ETo). At very high values of soil water availability, i.e. soil matric potential between -8 and -16 kPa, and after the canopy was fully developed, DSET had a 1:1 relationship with ETo. When root-weighted soil matric potential was greater than -16 kPa, the mean values of the ratio of soil water depletion rate to reference crop evapotranspiration (DSET/ETo) varied from 0.1 to 1.2 for 30-day periods between bud burst and leaf fall. Considering the full set of measurements, DSET/ETo was highly negatively correlated with soil water availability for all 30-day periods except those less than 60 days from bud burst. In the period 150 to 179 days after bud burst, 70% of the variance in DSET/ETo was accounted for by regression on soil water availability for values of root-weighted soil matric potential between -8 and -100 kPa. During this period a fall in root-weighted soil matric potential from -10 to -42 kPa was associated with a decline in the value of DSET/ETo from 1.3 to 0.6. At both high and low values of ETo, the ratio of DSET/ETo fell linearly with declining soil water availability. The changes in values of midafternoon stem water potential and stomatal conductance associated with this decline in DSET/ETo are discussed.
Grape must composition depends on irrigation management
Stevens, R.M. and Cole, P. (1987). In Proceedings of the Sixth Australian Wine Industry Technical Conference (Lee, T. ed). Australian Industrial Publishers, Adelaide, pp 159–64.
Abstract
A range of 6 soil matric potential regimes was established in a microjet irrigated vineyard (Colombard scion on Ramsey rootstock) by varying the soil water deficits at which irrigations were applied. The average amount of water applied per season to the most and least frequently irrigated treatments was 1342 and 740 mm, respectively, and the mid summer irrigation interval was 4 and 18 days, respectively.
The plant water potential experienced by vines in any of the treatments was found to be a function of the log of the absolute value of the root weighted soil matric potential (log ê RWSMP ê ). In response to decreasing soil water potential, shoot water potential decreased and stomatal resistance increased, indicating a direct response of the plant to soil water potential.
Indices of the plant water availability for the season were calculated by summing the daily values of the log ê RWSMP ê for each treatment during the season. The value of these indices (stress indices) increased as plant water availability decreased.
In both seasons (1984/85 and 1985/86) the vine yield and berry weight significantly decreased as the value of the stress index increased. The only must component which had a significant interaction with the stress index over both seasons was the malate concentration, which decreased as the value of the stress index increased. None of the other must components measured, ie Brix, pH, titratable acidity and the concentration of tartrate and potassium, had a significant interaction with the stress index in both seasons.
Our results demonstrate that vine yield is sensitive and that, except for malate concentration, must composition is insensitive over the range of soil water availabilities in this experiment. The irrigation treatments applied were representative of the range of irrigation practices encountered in the Riverland vineyards. Hence in some vineyards low soil water availability during part of the irrigation cycle may be causing a loss of yield.
Irrigation of grapevines with saline water at different growth stages. I. Effects on soil salinity and sodicity, vegetative growth and yield
Stevens R.M., Harvey, G., Partington, D.L. and Coombe, B.G. (1999). Aust. J. Agric. Res. 50, (In press)
Abstract
Mature field-grown grapevines, Colombard on Ramsey rootstock, grown in a semi-arid climate, were irrigated with saline water during any 1 of 4 growth stages within the season: pre-flowering, during berry development, during berry ripening and post-harvest. At other times, plots were irrigated with river water (EC 0.5 dS/m) as was the control throughout the season. Saline water (EC 3.5 dS/m) with a high SAR was produced by addition of sodium chloride brine. Soil cation exchange capacity was 14 cmolc/kg and, at the end of the trial, the soil exchangeable sodium percentage in the control was 6%, in the treatment salinised pre-flowering 13%, during berry development 20%, during berry ripening 20% and post-harvest 19%. Treatments were applied for 6 consecutive seasons. Vines were highly productive with the average yield in the control equal to 62 t/ha of grapes. Saline irrigation caused significant, but small, declines in yield in three seasons, in pruning weights in 2 seasons and in berry weights in 4 seasons. Effects on growth, once established, often persisted unchanged through one or more subsequent seasons of saline irrigation. The growth stage shown to be most sensitive to saline irrigation was berry development; saline irrigation during berry development reduced the yield by 7% and during berry ripening by 3% and pre-flowering it reduced the berry weight by 1%, during berry development by 6% and during berry ripening by 4%. The amounts of irrigation applied in each of the 4 growth stages were not equal and hence treatments did not receive equal additions of salt. Normalising data to remove this effect showed that the rate of yield decline per unit dS/m increase in the seasonal average salinity during berry development, 7%/dS.m, was 3-fold greater than the 2%/dS.m during berry ripening. We conclude that this scion/rootstock combination, grown under these conditions, can maintain high productivity despite ‘slugs’ of saline irrigation.
The relative effects of waterlogging and salinity on the growth of potted vines.
Stevens R.M., and Harvey, G. (1994). In the Proceeding of the 4th International Symposium on Grapevine Physiology. Giovanni Dalmaso Foundation, Torino, pp 607-610.
Abstract
In semi-arid South Australia, vigneron concern with soil salinity has led to over-irrigation which causes temporary waterlogging following irrigation. The relative effects of salinity and temporary cyclic waterlogging on growth were estimated from two experiments on potted Sultana vines. Growth of vines, with free draining rootzones, irrigated with solutions containing NaCl at 10, 20, 40, and 60 mM was 89, 76, 58, and 51 per cent of vines irrigated with a solution containing 2 mM NaCl. When vines irrigated with a 2 mM NaCl solution were subjected to cyclic waterlogging for 1, 3, 5, and 7 days in a 14 day cycle, growth was 43, 29, 30, and 26 per cent of that in vines with free draining rootzones.
Separating the effects of foliar and root salt uptake on growth and mineral composition of four grapevine cultivars on their own-roots and on Ramsey Rootstock
Stevens, R.M., Harvey, G. and Davies, G. (1996) Journal of the American Society of Horticultural Science 121:569-575.
Abstract
The effect of foliar salt uptake on potted grapevine growth and ionic composition was investigated in a split plot trial. The main plot was a two by two factorial consisting of separately irrigating the roots and foliage with non-saline or saline (NaCl 25 mM) solutions. The sub-plot was a four by two factorial consisting of four grape cultivars (Vitis vinifera cvs.) on their own roots or Ramsey (Vitis champini cv.) rootstock. Saline foliar irrigation over 27 weeks reduced total vine growth by 14% while saline root irrigation had no effect. Leaf Na and Cl concentrations were elevated by both saline foliar and saline root irrigation. The increases in concentrations with saline foliar irrigation were four times those with saline root irrigation. Leaf K concentration was reduced by saline foliar irrigation and increased by saline root irrigation. With saline irrigation of both roots and foliage the Cl and Na levels were highest in the leaves of `Shiraz', but with saline irrigation of only the roots `Sultana' had the higher levels of leaf Cl and `Shiraz' the highest leaf Na. Saline foliar irrigation had no effect on the concentrations of Na, Cl and K in the roots. In `Sultana', saline foliar irrigation did not affect the leaf concentrations of N, NO3-N, P, Mg, Zn and Cu. It increased the leaf concentration of Fe, and decreased that of Mn. Rootstock modified the effect of salinity on Fe concentrations. The B concentration was decreased by saline irrigation of either the foliage or the roots, but not by saline irrigation of both. In roots, saline foliar irrigation increased B in own-rooted vines, but not in those on `Ramsey' rootstock.
Grapevine response to transient soil salinisation
Stevens, R.M. and Harvey, G.C. (1990). In Management of Soil Salinity in South East Australia (Humphreys, E., Muirhead, W.A., and Van Der Lelij, A. eds). Australian Society of Soil Science, Riverina Branch, pp 211-19
Abstract
Transient soil salinization of irrigated Colombard/Ramsey grapevines was produced by substituting, for a number of different two month periods in the growing season, saline water (EC 3.5 dS/m) for irrigation water drawn from the River Murray (EC 0.5 dS/m). Irrigation with saline water produced a transient increase in the root weighted saturated soil solution (RWECe). This increase caused a decline in leaf water potential and an increase in leaf petiole sodium and chloride contents. There was no statistically significant effect on vine vegetative growth (pruning weights) or yield. These results are contrary to those predicted by the Murray-Darling Commission model which is designed to quantify vine yield losses due to salinity.
