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Glenn Lendon, Seed Increase Agronomist - Cotton Seed Distributors, outlines the seed increase program objectives and Quality Assurance protocols.

Glenn, what are some of the key criteria in selecting fields suitable for seed increase of these new transgenic varieties?

Craig, the criteria is the same as what we apply to our conventional fields. We’re looking for fields that are fallow and flood free. We’re also looking for fields that don’t have any association with fusarium or don’t have fusarium in them. So they can’t have shared machinery with a known effected farm or have overland flow from that farm. We also look at the isolation of the fields. That’s fairly important both for transgenic and for conventional varieties now.

The other thing we’re also doing is we’re trying to get economies a scale when we select a field. A lot of our fields are picked by contractors and so we are trying to put large blocks out there to make it more efficient for them and also efficient for the ginning organizations as well.

And obviously fields that are not back- to-back?

That’s correct, yes; fallow fields we’re looking for. Whether that’s a wheat fallow or coming out of corn or sorghum as long as it hasn’t been cotton in the field the previous year.

Ensuring varietal purity is obviously a key aspect of the seed increase program. What steps are taken at planting time to set this in train?

The varietal purity is our main aim in the seed increase program. We’re trying to maintain varietal purity well before planting. CSD has a limited generation seed certification scheme and what this means is that we limit the number of generations that can be produced from the breeder’s original selection. What that does is that protects all of the varieties from genetic shift and makes the varieties perform as the breeder’s intended.

Prior to planting we go out and inspect all the fields, making sure that they are fallow, that there are no sources of contamination. When it comes to the actual planting CSD delivers all of the seed onto farm itself. This gives us the ability to ensure that the right seed is going to the right farm.

Then we come to planting where the growers give us a call, we go out and inspect all the planting equipment. That means we dismantle the whole planter, we look at the planter plates and the planter boxes. At that time we also inspect the pallet that has actually been delivered to the farm just as a double check to make sure that seed has been delivered to the correct farm.

You mentioned fusarium before and the fusarium issue. What are the main requirements for seed increase crops and what procedures are in place to ensure this occurs?

Certainly we don’t place crops where there is known fusarium. We work closely with the Government agencies, whether it be DPI or NSW Ag to avoid putting pure seed crops in areas where there’s known fusarium. Once I’ve established my program I talk to Steve Allen. Steve has an in-depth knowledge of where Fusarium is throughout the industry and he signs off for me that I haven’t inadvertently placed a field in an area where there is Fusarium.

During the season we inspect all our pure seed crops four times. At each of those inspections we are looking for signs of fusarium. CSD has a fusarium protocol where at the seedling stage and just prior to first flower we walk every field looking for signs of fusarium.

Towards the end of the season when the crops close over we do a risk assessment on each field and we determine if a field has very high risk we’ll actually thermal image that crop, where we fly over it, we’ll take a picture and then we actually ground truth that picture if there are any hot spots in that field.

We also have arrangements with the gin so when we gin the pure seed crops the gins help us out by not putting the pure seed modules in areas where there are modules from known fusarium farms and then we don’t gin pure seed until the gin has been purged with one thousand bales of actually clean cotton to go through that gin. So there’s a protocol that CSD has put in place.

It’s been ratified by the industry. We work with all the government agencies or the ginning organizations to try and keep our pure seed crops clean of Fusarium and it’s just so important because Fusarium is seed born and we don’t want to spread it through the industry.

So just on that line with the fusarium, it would be important as well for on farm staff to know the symptoms of fusarium and then if they see anything suspicious to report it and those can be sampled?

That’s right. What we do, when we’re talking to our pure seed growers at the start of the year we supply them with copies of a “tractor drivers guide of fusarium”. We supply them with multiple copies of that and ask them to put them in all their vehicles and so when they are doing their inter-row cultivating or just spraying, if there are any signs of Fusarium they can detect it and let us know.

We can come and grab any suspect plants that they’re worried about and we also grab suspect plants if we’re inspecting the fields and we send them up to DPI for testing just to make sure that everything is right.

Could you outline some of the monitoring and sampling conducted in transgenic seed crops during the season to ensure their genetic purity?

Whether a seed increase crop is a Roundup Ready® or Bollgard® II or Bollgard® II Roundup Ready®, that seed increase crop is leaf sampled. We leaf sample all our generations of seed increase, whether it be pre-basic, basic or certified 1 or certified 2. Statistically we determine the number of leaves to be collected from each pure seed field. They are taken to CSD’s lab and a test for the gene of interest is conducted on those leaf samples and if there’s any problems with those, that pure seed crop is then re-sampled again and if it doesn’t meet spec that pure seed crop is dropped.

What other monitoring is carried out during crop growth, you mentioned field inspections and looking towards the end of the season. Do you look at yield estimates?

We do, as I said before we inspect our seed increase crops four times a year. One of those inspections is to certify the crop. So what we are looking for is we’re walking the crops looking for and counting the number of off types. CSD certifies all its seed increase crops to an international standard but what we’ve also done is we’ve developed our own standard, which is stricter than the international standard.

As I said we walk the crop and we’re counting the number of off types. If it goes above CSD standard we rouge that crop down to a nil tolerance and then we re-certify it again to make sure that we’ve got all the off types out. That certification program is actually audited by NSW Ag and we audit that annually to make sure that the seed we supply to growers is pure.

As you mentioned before we’re checking the crops for weeds, mainly the Noogura, Bathurst Burr and Devils Claw. We work closely with our pure seed growers to ensure that all of our crops are free of those weeds. A lot of the things we do with the pure seed crops we have large areas of variety and we can use them to gather some data for our E&D agronomists.

This year we looked at final plant height of a lot of varieties. We’ll be looking for instances of different diseases like alternaria and verticillium and we feed that information back to the CSIRO breeder’s. Our growers are good as well in terms of giving us feedback of how varieties are performing and all that is given to the CSIRO breeder’s about what varieties are doing and that information is all valuable.

At the end of the year we also do yield estimations, boll counts, we collect lint samples just to make sure that we’ve got enough seed to meet the industries demands.

Picking and ginning are obviously the other areas where maintenance of varietal purity is critical. What are some of the procedures carried out pre and post harvest?

Pre harvest the growers notify us of when they have defoliated the crops. There are certain chemicals that can’t be applied in defoliation mixes. The growers sign off that those chemicals like glyphosphate and other herbicides haven’t been applied to the crops.

There is evidence that different herbicides effect the viability if the seed, so we’re just ensuring that they haven’t been applied. At harvest time we come and inspect the picking equipment. We go through all the pickers, the module builders, the boll buggies and anything that is going to be used to harvest the crop. When the crops been harvested we come down and we sample every module.

Those module samples are taken back to our lab again. We do a germ test on every sample, we do a black seed recovery, which will tell us the amount of good seed that is going to come our of that field and if it’s a transgenic variety we actually do another transgenic test and the grower’s can’t move their modules until they pass all those quality assurance tests, especially the transgenic test.

Then we will inspect all of the module transport gear, whether that’s a chain bed or an infield loader and flat tops. We’ll come and inspect all those. At the gin we do more inspections; we’ll actually go and inspect the module pads and if they’re going to be dropped off on flat tops then we actually inspect the moon buggy as well.

Looking at the ginning side of it, would you outline what the main procedures are during ginning of these seed increase modules?

At ginning we get the gins to do a full clean down. They’ll go through all the equipment and the CSD staff member will go and inspect the gins. We’re looking for everything from the moon buggy to the module feeder, all the pre cleaning equipment, the gin stands and the seed bin. We also then arrange for transport of the seed ourselves and we go and inspect the fuzzy seed trucks to ensure that they are all clean.

Further Information: Glenn Lendon,  Robert Eveleigh, John Marshall, or Craig McDonald