Dr. Greg Constable, Program Leader CSIRO, explains trends being seen in fibre quality in the 2004-05 season

A significant part of the 2004-05 crop has now been classed. Can you give us a run down on how this year’s quality compared to the average of the last 5 years?

I have seen some of the data and working through strength firstly, there is a very low proportion of the crop that was below 28 grams per tex and that is a substantial reduction on where we have been in the previous years. There have been a few variety changes in the last couple of years that have probably addressed that.

Similarly for micronaire, a proportion of the crop harvested is greater than 5 or less than 3.5, however it is substantially less than what we have had in the last 5 years. I think this indicates that we have obviously been addressing the variety types in the wrong systems that give high micronaire for example and then being such a good long season its really prevented any low micronaire discount cotton coming through the system.

Finally for staple length, our long term average for less than 35 staple is nearly 5% of the crop and there is only 4% in the data that I have seen so far this season which is very good. However, about 14% of the crop is less than 36 staple so if the basis changed for that, then its this 14% we should be addressing in terms of future variety selection or crop management to avoid staple below 36.

As growers will be looking at their variety guides now and selecting varieties for next year they will see indicative numbers of length, strength and micronaire. Can you tell me how those numbers came about and how people should use them?

We often have feedback on these figures. The values come from our comparative trials where all these varieties are grown next to one another.

The purpose of the values in the variety guide is for people to compare a new variety with the one that they know. For instance, if a new variety has a length of 0.01 of an inch longer than a variety they have grown previously, it is that relative difference that we are wanting to emphasise, not the absolute value.

Obviously if you grew one of these varieties under dryland conditions, its length could be a 0.1 of an inch shorter and you are not going to achieve the value that’s in the variety guide.

So just to emphasise that all the values in the book come from comparative experiments where we have got each of those varieties in the same experiment and we are measuring the quality of them side by side.

So those comparisons are all consistent with each other and they are always going to have a similar relativity. If you have a variety with a longer length in your figures is always going to be a longer length regardless of the situation.

Yes, it will be longer. If you have a dryland site, the longer staple length varieties will still be a fraction longer. If you have perfect conditions and the lengths are good, the longer variety in the data set will be the longest. That relativity usually stays the same whatever the conditions.

There are a couple of new varieties being released to the industry in this next year in the 43, 80 and the 71 families. Can you tell us about the fibre quality of some of these particular varieties?

The status of fibre quality in our breeding program has been raised in the last 5 years and I hope that will start to be reflected in the releases over the subsequent seasons.

Some of the 71 family are in the shorter end of our ranges and they generally are excellent in terms of quality in the industry, however, if they have had any stress or conditions that hold back fibre lengthening they will be the first ones to gather any level of base or discount. All of our new varieties are longer and in fact the Sicot 71 Bollgard® released this year has a substantially longer fibre than 71 conventional or 71BR. So the options are there for people to have better quality cotton.

The 60BR that people are probably use to by now, people has better length and strength than many other varieties. The 43BR which is a new release this year likewise has good quality and they are alternatives for people that feel that they have got certain areas of their farm or certain management conditions that they need a variety with different quality characteristics, so there are options there.

We also have some Sicala 350B which is something that we developed a couple of years ago. This variety has very long fibre, its over 1 ¼ inches long in most circumstances. This is a product that may or may not attract the interest of some specialty products with the spinners.

In our program we have had a lot of other materials like that which we hope will move our industry forward in terms of the overall quality that the spinners see.

Within the Breeding Program there are varieties with similar or greater yield potential to our current Sicot 71 but with increased fibre length, strength and intermediate micronaire.

Absolutely, and that’s been the objective. Its quite a challenge with the performance that Sicot 71 does have but our targets are to actually exceed the level of yield in Sicot 71 and to also substantially increase the fibre properties and maintain the Fusarium resistance progress that we have made We aim also to have those sorts of options for the different production systems that people may have so as time goes on, these types of varieties will be delivered with Bollgard II® and Roundup Ready® Flex.

Further Information: 
Dr Stephen Allen, Robert Eveleigh, John Marshall,  Craig McDonald, David Kelly or James Quinn