|
Potato variety - Tarago | AG0079 |
Roger Kirkham, Toolangi
March, 1999 |  |
To view the Adobe Acrobat file, you will need the Adobe Acrobat reader. |  PDF 77 kb | |
A new potato variety, Tarago, was released by DPI in April 1983. It was bred at the National Potato Improvement Centre, Toolangi especially for the potato processing industry. Tarago produces high yields of round-shaped and medium-sized tubers when grown in the Koo Wee Rup district. These tubers have high specific gravity; the colour of crisps is excellent when Tarago is processed straight from harvest or from short-term storage. Tarago has a large yield advantage (usually more than 10%) over Kennebec, and is suitable for crisp processing. It is anticipated that Tarago will be grown for crisp processing in Victoria, particularly in the Koo Wee Rup district.
Description
- Upright and open habit
- Small leaflets with wavy margins
- Flower colour-purple
- Tubers set deep with buff skin colour that is mildly russetted
- Deep eyes
- Cream coloured flesh
- Length of growing season-125 days
|
Pedigree of Tarago
Tarago, while being tested, was identified as 71-18-4. It was first grown in the field in 1971 and, after five years selection at the National Potato Improvement Centre, Toolangi, was tested in Victorian potato growing districts. The pedigree of Tarago is shown in Figure 1 following:
Trials results
Yield
Tarago has been tested in district trials in the Koo Wee Rup area over a number of seasons. The results of variety trials at Bayles are given in Table 1, together with comparative figures for Kennebec and Sebago.
Table 1. Results of trials of Tarago, Kennebec and Sebago at Bayles
In three out of the four years, Tarago outyielded both Kennebec and Sebago. The average yield improvement over Kennebec was 15% for the four years. The yield improvement over Sebago was even greater but this was not a satisfactory comparison because planting dates were not optimum for Sebago crops. Block tests at Bayles, Cora Lynn and other properties have confirmed these results and have given yield improvements generally of 10% or more above Kennebec.
Storage
Figure 2. Results of storage trials done in 1980 and 1982 comparing Tarago and Kennebec in different storage facilities.
Kennebec remains the most reliable variety for long-term storage, and Tarago may not be suitable for this. It is recommended that caution be taken when storing Tarago tubers for processing and that crisp colour be monitored regularly during storage to avoid an undetected rapid decline in crisp colour.
Dry matter
Tarago has consistently had higher specific gravity than Kennebec in district trials at Bayles (table 2). The average increase in dry matter over Kennebec is 13%, which will result in about 13% more crisps for every tonne of potatoes processed. Less oil is used in the cooking process, the crisp quality is improved and the cost of processing is reduced.
Table 2. Specific gravity (SG) and dry matter percent (DM%) of Kennebec and Tarago tubers grown in district potato trials at Bayles in four seasons.
Advantages of Tarago
- High yield in comparison with Kennebec and other processing varieties
- High percentage of dry matter, resulting in a higher yield of processed product and lower production costs
- Light crisp or chip colour when processed immediately after harvest or after short-term storage
- Large tuber number per plant, particularly in comparison with Kennebec, so that oversize tubers are not a problem
- Tough skin resistant to mechanical damage
- Deeply set tubers, thus avoiding greening, sunburn and damage by potato moth larvae
- Some resistance to late blight and powdery scab diseases
- Ability to withstand very hot and dry conditions without undergoing severe stress.
Disadvantages of Tarago
- Flaky cream coloured skin and deep eyes give tubers a low consumer appeal when presented as a fresh product. It is not expected that Tarago will be grown for the fresh market
- Late maturity of Tarago will mean at least one extra irrigation in comparison with Kennebec, and probable delays in the commencement of harvesting. Defoliation may be required.
- Eelworm is one disease to which Tarago has shown significant susceptibility.
|
Growing Tarago for crisp processing
The optimum times for planting and harvest of Tarago in different districts for maximum yield and tuber quality will not be fully known for a number of seasons. In the meantime, it is suggested that Tarago be managed along similar lines to a Kennebec crop in terms of weed control, pest management, and planting practices. Tarago is usually slower to emerge and slower to close rows than Kennebec. Once rows are closed, the weekly water requirements are identical to those of Kennebec until about the tenth week after emergence. At this stage, further irrigation of Kennebec would be withheld if crisp processing was the intended end use, but Tarago would require at least one, and possibly two, further irrigations. Tarago should be grown with relatively low nitrogen fertiliser application. Tarago should not be allowed to become excessively dry during the haulm death period. Stem end problems may result.
The late maturity of Tarago may create some harvesting problems, particularly if it is intended for short-term storage. Slashing or other forms of defoliation may be required in order that Tarago crops can be harvested before cold or wet conditions set in.
Present knowledge indicates that Tarago is suitable for crisp processing when stored up until about the end of June. Storage beyond this date is not recommended until further information about the storage attributes of Tarago is available unless tubers are regularly monitored for deterioration in quality.
Tests during the past three seasons have shown that Tarago is suitable for processing when used immediately after harvest. The results of storage trials shown in the figure indicate that Tarago can be kept reliably for short-term storage, but with increasing risk after the middle of June.
The advice provided in this publication is intended as a source of information only. Always read the label before using any of the products mentioned. The State of Victoria and its employees do not guarantee that the publication is without flaw of any kind or is wholly appropriate for your particular purposes and therefore disclaims all liability for any error, loss or other consequence which may arise from you relying on any information in this publication.
|
