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Re: [compost_tea] Any Comments or reply to this?



Thanks for the other contributions re vines and control of PM. Does anyone have experience with Strike rust control in wheat using CT. What might be the required Fungi/bacterial range to control strike rust, any help would be appreciated.

Following are results from a trial of CT this year. Comments re the conclusions would be appreciated.

  

Compost Tea Trial

Preliminary results from Trial of Compost tea for control of Powdery Mildew in Cabernet Sauvignon and Shiraz Grapes, Redmond Western Australia. This area is considered a high risk area for PM and Botrytis.Lower risk are  Downy mildew Phomopsis and Esca.

Introduction

A trial was done to examine the effectiveness of Compost Tea (CT) in controlling PM and Botrytis. At the beginning of the trial it was agreed that regular monitoring of disease levels would be done and control measures adjusted as necessary to ensure minimal risk to the crop. The entire area of vines was sprayed no control area was left unsprayed. The vineyard contains 2 varieties Shiraz and Cabernet Sauvignon.

The CT used was tested at SFI Australia and showed high numbers of fungi (active and total biomass) with bacteria in good range.  Test results available at www.composttea.com.au

Compost tea (CT) was applied at 70 litres per ha using an air-assisted sprayer. Pressures were kept under 4 bar. No spreader sticker was used.

The vineyard was a young vineyard that had had a good history of PM control from the previous year. Trial area was 7 ha.

CT was sprayed on 28/09/02 22 days later on 22/10/02, 8 days later on 30/10/02 14 days later on 14/11/02, 14 days later 28/11/02 7 days later on 05/12/02 14 days later on 19/12/02, 14 days later 03/01/03, when due for CT the grower discovered 1% of 1% of bunches in the vineyard had Powdery mildew on them. It was noted that no Powdery was found on any of the Shiraz grapevines.The recommended spray interval was 7 days between CT sprays. The actual time between sprays was 13 days.

The grower made a decision to spray the entire vineyard with sulphur to control the powdery as this suited his spraying regime.

 It was noted by the grower and myself that we had made an error in application of the CT. The grower was diligent in picking up the CT early in the morning to spray in the cool of the morning however we realised afterwards that the last of the spray was going out in the middle of the day. This would result in damage to the Microorganisms due to UV radiation etc. This was particularly significant since the area that was sprayed last, (at midday usually), was the area where the outbreak occurred.

Conclusion

From the start of spraying CT at the end of September to the start of Jan 2003 there has been only CT applied to control PM. Other materials applied were Fish and Kelp between some of the CT sprays.

So for 3 plus months the vineyard was completely clean using only CT.

Reasons for small outbreak

- Spray interval too wide. 13 days was the average, this is too far apart. 7 days apart is indicated.

- Spraying organisms out in the middle of the day is likely to have reduced colonisation.

  1. Control of PM requires consistent use of CT at intervals of 7 to 10 days (weekly depending on weather). With leaf coverage of 50 to 70% bacteria and 2 to 5% fungi (Ingham SFI).
  2. The use of spreader stickers can help in achieving the above coverage.
  3. For logistical reasons it is better to begin spraying in late afternoon to improve colonisation of Microorganisms.

 

 The grower was pleased with the result and is planning to continue CT applications after Verasion (berry softening).

Regards
Mike Harvey.
New Life Soils, RMB 630 Kendenup WA 6323.
Ph 98514393 Fax 98514693 Mob 0427 514393.


This was posted on the BDnow! list server.
 
I personally find it very interesting, any comments?
 
daniel
 
Blame this one on me, folks, but one of the most astounding upshots
of this week's conference was the chance to meet with experienced
growers who have worked with compost tea and who have found teas to
be much less effective than we have heard people proclaim them to be.
 
Alan York asks people to ask the hard questions. He says a hard
question right now is 'Do you know of a vineyard that has effectively
controlled foliar disease with compost tea for three seasons.'  He's
willing to back this question down to one season. (The unusually dry
summer this past year has eleviated foliar diseases across the board,
tea or no tea.)
 
Vicki Bess, who is a compost tea advocate who spoke at this
conference, felt that the push to diversity and high counts is not a
push towards teas that really work on the soils or even the leaves.
She said, and Will Brinton concurred, that it is the feeds in the
teas that select the final microbial mix and these microbes were not
necessarily the ones that would do as good of works as ones commonly
dominant in dry compost. Will Brinton  stated that there is not need
for pumped up populations of microbials. He feels that this is
unfounded, unscientific hysteria. He went on to say that good compost
tea has all the microbiology a person needs for controlling foliar
disease - WITHOUT BREWING IT other than we do already!! Think about
it folks:
 
Even better: Compost tea and brewer sales people in Pennsylvania have
received letters from the EPA telling them that they cannot sell
their products as disease control products because there is NO
SCIENTIFIC EVIDENCE THAT THEY ARE EFFECTIVE.
 
Again - I'm sharing this info for your own evaluation. I've got egg
on my face, of course.
 
-Allan
----- Original Message -----
Sent: Thursday, January 30, 2003 10:57 AM
Subject: Re: [compost_tea] Re: Why have regs, and the ICTC

> Elaine,
> Thanks for your response, and all your points were well taken. But
> believe me, it's just the tip of the  iceberg.  I too am eagerly waiting
> for responses to Laura's questions, and I believe that since this was
> the venue chosen to solicit members, this is where the answers should
> be. I feel this was just a retaliatory response to the "big industry"
> association, and might lack the necessary thought and substance to be
> viable. I hope I am proven very, very wrong. I haven't eaten crow for
> quite some time, but I ALWAYS carry some A-1 sauce with me.
>
> Bill Baranick
>
>
>
soilfoodweb@aol.com wrote:
>
>
>
>
> To unsubscribe from this group, send an email to:
>
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>  
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