Last season, the CSD Extension and Development team conducted Segmented Picking within many crops across the industry; providing a valuable insight into yield and fibre quality. In this weeks Web on Wednesday, CSD Goondiwindi Agronomist David Kelly discusses Segmented Picking, how it is done, and its uses.

With segmented picking we come into a crop that is just ready to harvest and we divide the fruit up into a number of sections. We divide the main stem up into sets of four fruiting nodes.

We also separate out first and second position fruit. This particular plant has got all first position fruit. This allows us to get a good picture of where yield is coming from in regards to different parts of the plant.

When we pick these plants we place them in different sections within what we call our ‘boll box‘ and at the end of the day we have the number of bolls that came from each section out of a certain area and we also have the samples retained. We keep these samples, we get them ginned and we then get those lint samples HVI tested (we are mainly interested in length, strength and micronaire).

From this information we can determine things like
• what proportion of yield is coming out of different parts of the plant,
• how the boll weight varies in different parts of the plant and
• how fibre quality varies at different parts of the plant.

This is particularly useful is that when we have a result of a trial, (irrigation management or variety for instance), we can help explain why that result has occurred and what we can also do is look at what value is coming from different parts of the plant (for instance, what value is there in the top bolls or the top of the plant?, what value is there in the bottom bolls of the plant?).

We can also overlay this with management that has happened during the season and also very importantly this year with climatic conditions during the season. We can look at the climatic conditions that occurred when a particular boll was flowering and maturing and look at what impact that has had on its fibre quality, its size and overlay that with the distribution of fruit within the plant. For example, is there a lot of fruit on the top and none on the bottom and why has that occurred, is it a management or climatic factor

Some of the highlights we got out of the segmented picking work last year were some good comparisons between varieties. We particularly looked at comparisons between 71BR and Sicot 289BR and why there were variations in yield and fibre quality between those two varieties.

Last season we were very fortunate to be able to have a look at some of the exceptional yielding crops across the industry; crops that yielded in excess of 5 ½ and 6 bales per acre.

We were able to see where the value was coming from in terms of yield in those crops and we were also able to look at some contrast between those very high yielding crops and some crops that didn’t do quite so well to try and work out what the differences were; for example was there a difference in fruit retention?, was it a different in plant size?.

It provided some great answers and really good pointers in terms of the management of some of our varieties.

In this seasons work we have already sampled many crops and we are currently analysing that data. Hopefully we will come up with some good answers of some of the situations that have happened in this years crop.

Stay posted for the results of this segmented picking work and all of the other of our extensive research program at our 2006 Information Tour. Also come and see us at the Australian Cotton Trade Show or give any of the Extension and Development Team a call.

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