Replanting and Thrips Control Case Study
Many times we see problems and help people make decisions and never get a chance to see the results. I thought I would set up a case study to follow this year and consultant, Mary Wilks has agreed to help us follow this 105 acre field. The field was originally planted in DPL449BR. The grower was trying to decide if replanting would be advisable due to tremendous thrips pressure and less than desirable stands. Below are some pictures taken of the field about May 29th:
This is how Mary described the field to me:
This field was planted pretty early and has currently 4 scrawny true leaves on it. It suffered heavy thrips pressure (and has been treated twice already with orthene at 6 and 8 oz/ac) and still has thrips in it.
It had a lot of cold rain and cotoran injury. We have put off replanting this as long as possible (the grower has just finished planting all the other farms for the first time). I looked it this evening and you can finally see a little green starting to show down the rows.
The stand was excellent initially and is still good, despite some plants that have died. I think the cotton will grow out of this but it just looks so pathetic. Some of the stems are darkened despite new green growth (not like seedling disease but just dark instead of white). It normally wouldn’t be such a hard decision but it’s about 105 or so acres of really good land involved.
After talking with Mary I suggested that she might want to replant the “worst” areas and keep the rest. In other words, there is probably not a right answer at this point. The grower, Mary and county agent, Authur Whitehead, decided to replant half of the field on May 30, 2006.
The half they decided to replant was originally planted with Avicta treated seed. This area was replanted to DPL444BR with Temik applied in-furrow.
The half of the field they decided to keep (DPL449) alternates between Temik and Avicta thrips treatments every 8 rows. Orthene was applied for a third time on May 31, 2006. They noted that the Temik treated cotton looked better and that is why that half of the field was not replanted.
We will have 2 comparisons to follow through the year, including harvest and fiber quality. One comparison is obviously was replanting warranted or not in this situation. We will have no way to statistically analyze this comparison but it will be interesting
We will be able to compare the Avicta versus Temik treatment for the early planting in this year. Below is a picture of the two treatments taken on June 5, 2006. Temik treated plants on the left and Avicta treated on the right. Mary also noted that the replanted area had excellent emergence on that day.