Improved orchard productivity and water use efficiency using modern irrigation and tree management techniques in northern China

LWR1/1994/047: Improved orchard productivity and water use efficiency using modern irrigation and tree management techniques in northern China

China

Agriculture Victoria, Australia

Mr Ian Goodwin
Phone: 03 5833 5222
Fax: 03 5833 5299
Email: ian.goodwin@dpi.vic.gov.au

• China Agricultural University, China

$997,390

01/01/1996 - 31/12/2000

01/07/2001 - 31/12/2001

Dr Ian Willett

There are about 4.8 million ha of orchards in provinces of northern China, growing apples, pears, peaches and grapes. On the whole, the trees and vines grow well, but their yields fall far below those that could be achieved with different management, smaller leaf canopies and efficient irrigation practice.

The problem was that few of China's many orchard managers and workers knew of, or used regulated deficit irrigation (RDI). Most orchardists flood-irrigated the trees whether or not they needed water, and applied inappropriate quantities of nitrogen fertiliser. The trees, many of which were growing on deep fertile soils, reached huge sizes and took several years to bear small crops of fruit.

This was ACIAR's first development/extension project, based on two previous ACIAR research projects (Nos 1985/078 and 1990/048) going back to 1988. The project challenge was to spread the message that efficient irrigation and planned tree shape were more effective for fruit production.

The overall objective of the project was to stimulate adoption of better orchard techniques by demonstrating that restriction of the trees' canopy development, giving them minimal water during the flush of shoot growth then watering generously during fruit set would lead to larger crops of good-sized fruit.

A project site in each of four major fruit growing areas undertook to demonstrate effective tree management at a commercial scale. Scientific, extension and orchard management staff were trained to understand the interaction between climate, soil, water, tree nutrition, tree architecture, growth and production.
The water-saving policies of the Chinese Government had been ineffective. In an attempt to change workers' wasteful habits the Chinese Agricultural University, the Water Conservancy Bureau and two Australian companies installed micro-irrigation equipment in orchard areas totalling about 640 ha in Beijing Municipality, Shandong Province, Shanxi Province and Xinjiang. The sites either had poor water supply or environmental problems, or the workers were interested in micro-irrigation. It was intended that micro-irrigation demonstrations linked to improved yields would have an impact on work practices.
In Australia the project helped to develop a computer simulation model from existing models that describe aspects of fruit cropping. The model was intended to evaluate the effects of tree shape, size, density, water supply, water quality and root distribution. An expert system incorporated later into the model would help technically-trained managers and extension officers make decisions about irrigation scheduling, tree nutrition and the management of water, soil, crop and canopy.

The project demonstrated technologies at commercial scale in four regions of China with moderate success. The main failing was insufficient appreciation of the local context and politics, and reviewers recommended that more attention be paid and more resources allocated to identification and selection of demonstration sites for future extension activities.

The Chinese scientists produced detailed manuals, a video, and other training aids for the application of micro-irrigation and regulated deficit irrigation in deciduous fruit trees. Despite being an extension project the program also helped to markedly increase research capacity at the China Agricultural University and the Forestry and Pomology Institute of Beijing, promising long-term positive consequences for the quality of research and undergraduate training in these organisations.
There were signs of positive community impact in China through exposure to potentially more efficient technologies, but greater involvement of extension practitioners (sociologists and community specialists) with specialist China knowledge will be needed to ensure a successful outcome. Reviewers recommended that future activities should address issues surrounding the adoption process.
FruitSim, a computer simulation model for fruit tree phenology (climate-related effects) and canopy development was produced in Victoria. However, it had a major shortcoming in its ability to model rootzone soil water processes. The major obstacle was a lack of time, not technical difficulties and additional resources were recommended to support the completion of the soil-water module. The project produced an expert system based on the above model, but its usefulness will be greatly enhanced when the soil-water module is completed.