Print This PageNew Cotton Variety - Sicot 71BRF
Since its release in 2004/05 Sicot 71BR has been an integral part of the Australian cotton system. A combination of consistently high yields, broad regional adaptability and technology traits has seen it become the most popular cotton variety grown in Australia. With the initial release of Sicot 71BRF through the CSD Members Ballot system last season, it is now timely to look at the performance.
High Yield Potential
Sicot 71BRF will be the highest yielding Bollgard II® Roundup Ready Flex® variety in Australia in the coming season. Commercially, growers have been able to extract
excellent yields from this variety across all regions. Within the CSD variety trial program, it has performed beyond expectation and has been placed first or second in over 90% of the trials it was entered into. In fully irrigated trials (32) ranging from Emerald in the north, Hillston in the south and Bourke in the west, it has yielded on average 10.87 b/ha (4.4 b/ac). In five CSD dryland trials in what has eventuated to be an excellent year for dryland production, Sicot 71BRF has averaged 3.97 b/ha (1.6 b/ac).
Table 1: CSD Variety Performance Comparison of Sicot 71BRF, Sicot 71BR and DP210BRF comparing yields and turn out from 08/09.
| Sicot 71BRF | Sicot 71BR | DP 210 BRF | |
| Diff from 71BRF | Diff from 71BRF | ||
| Yield b/ha (Irrigated) | 100% | +0.9% | -13% |
| Yield b/ha (Dryland) | 100% | N/A | -16.5% |
| Turnout | 39.74% | -0.63% | -2.42% |
| No. of Trials | 2 | 14(2) | |
| Note: Numbers in red are a decrease from Sicot 71BRF, blue numbers represent an increase | |||
Improvements in Fibre Quality
Sicot 71BRF shows a dramatic improvement in fibre quality attributes over Sicot 71BR, especially in terms of length and micronaire. Although having a very high yield potential, Sicot 71BR, did have an inherently shorter fibre and higher micronaire than other commercial varieties. These attributes predisposed this variety to below base grade fibre length and high micronaire reading if growing conditions were not ideal.
Table 2 CSIRO small plot data from 06/07 and 07/08 seasons
 |
Data from 19 x CSIRO Trials over 2 seasons | |
| Sicot 71 BRF |
Sicot 71 BR |
|
| Relative Yield % | 103% | 100% |
| Staple | 1.22 | 1.16 |
| Micronaire | 4.3 | 4.7 |
| Strength | 30.8 | 30.4 |
| Data Courtesy of the CSIRO Cotton Breeding Team | ||
Fibre Length: Sicot 71BRF has a significantly longer staple than Sicot 71BR – -up to 0.06 inch (2 32nds of an inch) longer, making it very similar to Sicot 70BRF.
Micronaire: Sicot 71BRF has a finer fibre than Sicot 71BR meaning it has an inherently lower micronaire. CSIRO and CSD data shows micronaire levels 0.3 – 0.4 less than Sicot 71BR and approximately 0.05 greater than Sicot 70BRF. As a part of the CSD 08/09 Variety Trial program Sicot 71BRF was placed into five dryland trials. Importantly the Sicot 71BRF not only produced the highest average yield across these trials but also the best aggregate fibre quality. Sicot 80BRF has been the staple dryland variety since its release three seasons ago. In two of the five trials the Sicot 80BRF recorded fibre length below base grade. The ability of Sicot 71BRF to deliver good yields and fibre quality in conditions which were not ideal in these dryland trials is a good demonstration of the robustness of this variety in maintaining base grade fibre length. This is a dramatic improvement over Sicot 71BR.
Table 3: CSD Variety Performance Comparison of Sicot 71 BRF and Sicot 80 BRF in 5 dryland trials (08/09 season)
| Sicot 71 BR | Sicot 80 BR | |
| Yield (b/ha) | 3.97 | 3.87 |
| Turnout | 39.05 | 37.2 |
| Length Dec | 1.14 | 1.11 |
| Strength | 29.88 | 30.7 |
| Micronaire | 4.18 | 4.28 |
| Uniformity | 80.74 | 80.84 |
| No of Trials | 5 | |
Similar to other members of the Sicot 71 suite, it is important to maintain an adequate irrigation and nutrition strategy to extract the very high yields from this variety but the improvements in fibre quality will reduce the risk of short staple associated with Sicot 71BR if adverse conditions were encountered
Disease Resistance:
Sicot 71BRF has greatly improved Fusarium resistance over Sicot 71BR table 4) and this was clearly noticeable in the field during the 2008-09 season. Verticillium data for Sicot 71BRF is limited (one trial) although this indicates a V.rank similar to Sicala V-2 which is the standard measurement for verticillium. More V-rank data will be gathered next season.
Table 4: Disease rankings (number in brackets indicates number of trails)
| F Rank | V Rank | |
| Sicot 71 BRF | 116 (6) | 104 (1) |
| Sicot 71 BR | 101 (14) | 115 (5) |
| DP 210 BRF | 68 (4) | 108 (4) |
Source: CSD Facts on Friday 3rd July 2009, compiled by the CSD Extension and Development Team.
