In this weeks Web on Wednesday Adam Kay & James Quinn speak with Greg Constable & Will Kirkby about whats involved in growing pima cotton.

Dr Greg Constable, CSIRO Plant Breeder

There is a lot of interest from growers in Pima as there often is when upland prices are down. Can you explain some of the key things in making the decision about growing Pima?

I find Pima very interesting too. It’s quite an exciting crop to work on and we have had some small input to that breeding area in the last 15 years or so. The interest is that Pima is a different species to what our normal crop is and it has very good quality, with a longer, finer and stronger fibre, and also with a good lustre in many cases. So there is a sizable premium there in some cases. Performance-wise it is about 70 – 80% of the yield of an upland variety in a similar region, so the 70% number needs to be taken into account with regard to relative prices of the different products.

One of the things that you need to consider is quality. Can you make some comments about that?

Yes it is longer so where normally you might be getting 1.15 inches in an upland variety, the Pima’s are generally hitting about 1.40 or maybe a little bit more so they are substantially longer and that really is something that premium spinners or premium yarns are after. The strength is there also so they can make much better product.

There are a few things to watch out for on the downside though. Can you enlighten us on those?

Historically Pima has been very susceptible to diseases; with diseases, probably with the exception of verticillium wilt (there is some good resistance to verticillium wilt in that species). So locally in Australia, Bacterial Blight has been a real ‘doozy’ that any of the areas. Where that disease was an issue it was a major factor in production failures at times with Pima. Also Fusarium wilt, most of the varieties that we were using up until recent times were very susceptible to Fusarium, highly susceptible I must say. Pima is also very susceptible to Alternaria.

But there is some good news on the development front with those diseases?

Yes a little bit. We started out with this program a long while ago to get bacterial blight resistance and we have eventually got to that point. In that time, Fusarium wilt has also occurred and now we do have good Fusarium wilt resistance as well as bacterial blight immunity in our Pima breeding material now. Unfortunately we don’t have Alternaria resistance.

Could you mention one of the other ‘watch out for’ issues which is weather damage at harvest?

If you look at where the species Pima or Egyptian cotton is grown in the world there are really arid dry places and the fact if that during boll opening (in particular), the crop is very susceptible to down-grading with weather or humid conditions. This is to such an extent that the fibre is worth less than what upland cotton is worth if it has had that downgrading from wet weather. That is why at the moment in Australia it’s grown at Bourke, Tandou, Hillston. With the Bacterial Blight resistance there we believe we can come a little bit further East and maybe North but I believe we still need to be a bit careful and that is a risk issue as much as anything else. It won’t happen every year in more northerly and easterly places but it is a risk issue.

Is there anything in the management that you think needs to be pointed out that is different to upland cotton?

Well surprisingly not. All the same principles apply in terms of fertilisers, irrigation, growth regulators. It is a little bit more difficult to defoliate; you have to be more patient with defoliation. It is actually more cold-tolerant surprisingly than upland cotton so generally it grows faster in cooler weather than what upland cotton does; which is a good thing.

One of the things we haven’t got yet is any transgenic traits in Pima so growers are using conventional chemistry to control Helicoverpa?

Yes that is the case. Monsanto up until now has been quite reluctant to put any of the traits, Bollgard® or Roundup Ready into Pima. There is now Roundup Ready® in Pima in the US and Monsanto will be working towards getting approvals for having Roundup Ready® and Bollgard II® in Pima varieties.

Could you just take us through the varieties that growers have available to them in Australia because it use to be only one but now there is a few?

Originally there was the Pima S6 and that was superseded by Pima S7, both from Arizona. In recent years I imported some lines and we have found a line from another breeding line from Arizona that was much better adapted than those two varieties to at least the longer season areas of Pima production; areas such as Bourke. That is now available to growers as Pima A8 and the A can stand for Arizona or Australia whatever you like. But closely following behind that, is our breeding lines and the most common ones of those that we have got at the moment is CPX42. It will get a Sipima name eventually next year no doubt and it has immunity to bacterial blight, good fusarium resistance and really good quality, very strong, long and fine.

So outside your area of expertise there is two other key points though that we need to point out for people considering growing Pima. Could you just go over those two things?

Well ginning for a start; Pima needs to be processed in a Roller Gin and there are only two of those available at Bourke and Tandou and it is much more expensive as the ginning process is slower. Secondly, the marketing; there is no futures market and there are fewer traders in that area so really people considering going down that route should line up a ginner and also line up a merchant before they commit too far down the track.

So where would people get further information on Pima?

CSD has made a nice brochure about Pima. We have had a few people put a lot into that; Stephen Allen in particular documenting disease issues and agronomy issues in consultation with Pima growers. So I think it is a really good start for what people might just read up on.

Will Kirkby, Cotton Grower, Moree

Will, you grew Pima here at ‘Glen Prairie’ last season for the first time. Can you give us an indication of how it went?

We grew 50ha of Pima A8 and it went 2.83 bales/ acre. It was in a fallow field that had barley in it the year before and it had been re-lasered but we did not rip it so there were a few compaction issues. I think that hopefully we can get a bit better yield than that.

With the management last season, did you find it any different to how you managed your upland cotton?

We weren’t really sure how it was going to pan out because we had heard a lot of information from people especially how they did it and so we were guided a bit by what they told us. It was very similar to Sicot 71 conventional in its maturity but we weren’t aware of that. We thought that it was going to be a lot more indeterminant but it ended up being quite determinant and finished up at about the same time as the Sicot 71. Heliothis wise, it seemed to be less susceptible or not as attractive so I think this year we will probably not spray it as much. The water management was something that we found we might have to change a bit, even though we weren’t that far out last year because it is a more determinant crop than we anticipated we probably watered it being an indeterminant crop rather than more determinant crops. This year I think we will change our water management a little.

Obviously you are going to try Pima again this year; what else do you think you have learnt from last season that you may change, aside from your watering regime?

As I said before, our monitoring of insects showed it didn’t seem to be as attractive last year so hopefully this year it won’t be as attractive as the conventional cotton again, although we will only have Bollgard II® here other than it so I suppose we won’t really be able to tell.

Our fertilizer regime will be exactly the same as last year. We put a pre-plant application of 250kgs of urea out. We did that last year and we did that again this year and we might also put some Potassium on at the same time and water run a bit of Nitrogen; probably 5 units. Other than that I don’t think we will manage it any differently than we would a Sicot 71 conventional crop.

ADDITIONAL INFORMATION:

Facts on pima cotton: http://www.csd.net.au/downloads/fof/Facts-on-Friday-6-10-06.pdf