Charles Sturt University
Charles Sturt University

Sustainable Viticulture

Sustainable Viticulture

Carbohydrate accumulation in reserves and root growth of grapevines after harvest

Objectives:Harvesting the grapevines

  • Investigate the factors and mechanisms contributing to carbohydrate reserve accumulation and root growth after harvest.
  • Specify how to manage vines to optimise carbohydrate accumulation after harvest until leaf fall and early shoot growth.
  • Implement an industry strategy to optimise the post-harvest period for carbohydrate pro-duction, root growth and nutrient uptake.

Outcomes:

  • Better understanding of the factors that impact on carbohydrate storage after harvest.
  • Strategies to optimise starch and nutrient reserve accumulation and root growth.
  • Industry training to widen knowledge of the effect of vineyard practises on carbohydrate storage and vine productivity.

Project Co-ordinator- Dr. Bruno Holzapfel

Rootstock influence on the relationship between vine performance and grape quality

Project Aims

  • Investigate the physiology of rootstock effects on scion vigour and yield.
  • Explain interactions between grape quality, vigour and yield in grafted vines.
  • Provide a basis for better decisions relating to rootstock selection and management.

Outcomes

  • Demonstration of direct rootstock effect on inflorescence flower numbers and yield.
  • Possible physiological explanations for the effect of Ramsey on vine vigour.
  • A better understanding of the relationship between grape quality and yield in grafted Shiraz.

Project Co-ordinator- Dr. Bruno Holzapfel

Ripening grapes to specification

Project AimRipening grapes to specification

Identify manageable factors that determine grape composition and quality

Outcomes

  • Colour and yield vary significantly between vineyards in the Riverina (and years)
  • Relationships between colour, yield and TSS differ between vineyards
  • High or low yield does not necessarily mean low or high colour

Project Co-ordinator- Dr. Bruno Holzapfel

Nutrition and irrigation strategies to minimise vineyard inputs, reduce environmental impact and improve grape quality

Project AimsIrrigation

  • Minimise vineyard water and nitrogen inputs and outputs by using novel irrigation and nutrition strategies
  • Understand the interactive effect of irrigation and nutrition in grapevines
  • Further knowledge of nutrition and water management on bunch structure, berry composition and disease incidence

Outcomes

  • Reduce nitrogen and water use and loss from vineyard system
  • Improve knowledge of vine nutrient uptake under different water and nutrient supply regimes
  • Improve grape quality, reduce disease incidence and use of fungicide through nutrition and irrigation management

Project Co-ordinator- Dr. Bruno Holzapfel

Improved water use efficiency for irrigated vines

Project AimsEfficient water use

  • Develop water application recommendations (ML/ha) and strategies to minimise the salinity risk to the soil and grapevines of reduced, highly scheduled irrigation volumes.
  • Establish benchmark data for the long-term salinity implications of reduced irrigation applications to grapevines.

Outcomes

  • Increased adoption of best management practices for improved water use efficiency of irrigated vines.
  • Increased understanding of the impact of salinity on vines receiving reduced irrigation volumes.
  • Integration of results from irrigation/salinity field studies and research trials into current grape industry extension methodologies.

Contact- Mr Graeme Sanderson

Precision Viticulture

Project AimsPrecision Viticulture

  • To quantify the nature and extent of within-vineyard variation in grape yield and associated fruit and vine characteristics in representative vineyard sites;
  • To investigate the utility of high-resolution airborne remote sensing as a means of detecting and mapping grape productivity parameters (initially red varieties) including yield, colour and phenolics.
  • To scope the opportunity for adoption of precision agriculture technologies in the wider Australian grape and wine industry.

Project Outcomes

  • New and cost-effective methods of monitoring and measuring within vineyard variability in grapevine yield and quality attributes including remote sensing.

Project Coordinator- Dr John Louis

Floor Management Systems

Project AimsFloor management trial - showing treatment effect on canopy

  • Develop sustainable vineyard floor management systems suitable for Australian conditions, using the Swiss model for Integrated Production (IP) as a basis.
  • A pilot feasibility study in two climatically different regions (hot/dry and mild/wet) is conducted for three years.
  • In the first year, three different treatments (slashing, complete spray-out, under-vine spray-out) were applied to the vineyard floor and the biological system was assessed (insects, plants, nematodes and other soil organisms).

Project Outcomes

  • Future trials will be based on the outcomes of this study along with industry consultation and participation.
  • On-farm trials will be conducted as part of the CRCV's Viticare program and by industry collaborators.
  • Results will be used to reduce reliance on agrochemicals (pesticides, herbicides, fertilisers) and to maintain cost-effectiveness and wine quality without compromising the environment.

Project Co-ordinator- Dr Ron Hutton

Vineyard microbial soil health

Background

The "Vineyard soil health and microbial biodiversity under different cover crop and floor management systems" (an ARC Linkage project) and the soil microbiology aspect of the GWRDC project "Floor management systems to reduce vineyard inputs and improve grape quality" aim to investigate the affect of floor management systems on the soil microbe biodiversity in vineyards, and how these impact on grape quality. These projects will attempt to identify cover crop and floor management practices for improved vineyard sustainability, hopefully with the output of reduced vineyard inputs and improved grape quality and vine health.

Aims

The aim is to examine soil health in the vineyard by monitoring the population dynamics and diversity of the soil microbial (fungal, bacterial, actinomycete) community under different vineyard cultural practices, with an emphasis on microbial populations capable of suppressing soil borne disease. Soil health can be seen as implying "ecosystem sustainability, diversity, functional connectedness, and resilience in response to a disturbance or stress". Using this definition, disease suppressiveness, for example the ability of soils to cope with stresses such as root disease pathogens and conditions conducive to root disease, can be viewed as one of the characteristics of a healthy soil.

Microbes which inhabit the plant rhizosphere, the region of soil directly influenced by the root, can contribute to soil disease suppressiveness, reducing the effect of many soil-borne diseases. Disease control by rhizosphere microbial communities also has been shown to extend to systemic and foliar diseases through the activation of the plant's chemical or physical defence mechanisms.

Soil disease suppressiveness may be induced by cultural practices that increase soil organic matter, increasing the biodiversity of the soil and the competitive ability of the indigenous microbial community on the root. Suppressive soils have generally been found to have higher soil microbial activity than conducive soils (i.e. soils conducive to disease) because rhizosphere or bulk soil microbial communities with high diversity are more likely to have a larger number of candidates with the ability to compete with pathogens (see Fig for examples of soil bacteria able to control vine diseases in vitro ).

Colletotrichum acutatum (cause of bunch rot in sub-tropical regions of NSWEutypa lata (cause of Eutypa die-back)

Fig : Soil biocontrol bacteria inhibiting the growth of PDA colonies: a) Colletotrichum acutatum (cause of bunch rot in sub-tropical regions of NSW) b) Eutypa lata (cause of Eutypa die-back).

An important aspect of this project is to investigate the natural biocontrol bacterial and fungal populations in the vineyard soil. Continuous plant covers such as permanent swards increase the soil organic matter, leading to improved soil microbial activity and biodiversity. We are interested to see how the soil microbial populations change and whether this results in improved disease suppressiveness. In the long term, can a permanent sward lead to lower disease incidence and severity in the vineyard?

Melanie Weckert Research Horticulturist/Plant Pathology
National Wine and Grape Industry Centre, Wagga Wagga Agricultural Institute
Phone: 02 69332720, e-mail: melanie.weckert@dpi.nsw.gov.au.