5.  Blossom End Rot-How is it caused and how to reduce incidence

Causes and Remedies for Blossom End Rot in Peppers, Tomatoes, and other Solanaceous Vegetables

 

Blossom end rot is a physiological disorder caused by factors other than pathogens or insects. In 1914 Brooks described blossom end rot in tomato in the journal Phytopathology but did not explain its exact causes. The disorder appears as a water-soaked region, often chlorotic, on the blossom end of large fruited varieties of tomato, pepper, eggplant, watermelon and zucchini grown either in the field or in greenhouses. Symptoms of blossom end rot usually occur within two weeks after fruit set. Blossom end rot symptoms usually occur on the earliest fruits but it can also occur on later fruits if conditions are favorable. Long fruited varieties are more vulnerable to blossom end rot than round fruits, but it can also occur on round fruits as the following photo illustrates. However, no blossom end rot symptoms have been seen on wild tomatoes and they rarely occur on small fruited varieties like cherry tomatoes. The disorder can also occur on the inside of the fruit in the tissue surrounding the seed where it is called “black seeds.” The incidence of blossom end rot is infrequent in most properly managed fields, but it can be very serious under certain conditions. Tomatoes showing blossom-end-rot.

 

Since 1942, most experts have agreed that the disorder is likely caused by calcium deficiency in the distal end of the affected fruits. However, there are other factors that have also been linked to blossom end rot incidence, including low tissue phosphorous and manganese, high tissue nitrogen, magnesium, and potassium, high soil salinity, drought stress, too much water, high temperature, high light intensity, location of the fruit on the plant, root damage, and cultivar. Most of these factors, however, appear to affect plant growth and so their effect may be indirectly related to the incidence of the disorder compared to calcium. Calcium controls the process of cell expansion and serves as a messenger for cell to cell communication. Calcium is delivered into the fruit via the xylem vessels. There are fewer and narrower xylem vessels at the blossom end of the fruit where the rot is likely to occur. Also the xylem to phloem ratio is low and there are fewer vessels in the seed cavity in the blossom end of affected fruits. Combined, these factors are believed to be the reason why the rot develops on the blossom end of the fruit. Before you jump on your tractor and start spraying the plants you need to be aware that blossom end rot is not a simple disorder that can be cured with calcium for many reasons. Studies have shown that there is no critical level for calcium that can induce the rot, other elements beside calcium can also contribute to the rot development, and some hormones and high temperature have also been shown to induce the rot. Even when assuming that calcium is the main reason for the rot, some fruits like tomato are not likely to respond to calcium treatment. Tomato fruits do not have openings (stomates or lenticels) on their skin and so it is difficult for calcium to move through the skin and into the fruit, especially during the critical times at the early stages of development. Here are a few tips on how to prevent blossom end rot from developing in your tomatoes, peppers or other fruits.

1. Check soil pH the previous fall before planting and add non dolomitic lime to correct low pH.

2. Check the soil organic matter. Subtract the amount of nitrogen in the soil from the total amount of nitrogen that the plants

need for optimum growth.

3. Avoid adding too much Mg, K, or other cations that compete with calcium unless the plants show visible signs of deficiency.

4. Do not use ammonia type fertilizers, use nitrate forms instead. Ammonia fertilizers compete with calcium uptake.

5. Choose cultivars that grow slowly, produce less foliage, and produce medium size fruits. Cherry tomatoes do not develop blossom end rot.

6. Avoid planting too early in the season.

7. Do not severely prune the plants.

8. Avoid damaging the root system by cultivating away from the plants.

9. Adding too much nitrogen, especially early in the season will likely lead to blossom end rot development.

10. Maintain adequate soil moisture. It is better to irrigate frequently at low rate than to irrigate once at high rate.

Spraying calcium, regardless of its form, will not eliminate blossom end rot on affected fruits. The three most important factors that will likely minimize blossom development in your tomatoes, peppers or eggplants are to monitor the level of nitrogen carefully

(divided the rate into smaller doses and use nitrate nitrogen), prevent fluctuation in soil moisture, and keep the soil pH at 6.5 to 6.8. If you can manage these three factors, you can manage blossom end rot.

6.  Corn Ear Worm Control

 

 

7. APHIDS INCREASE

Email Recd Sat 8/24/07
By Dr. Chris DeFonzo MSU Dept of Entomology

Quick take home messages:
* Aphid numbers are increasing in the eastern Great Lakes area, dramatically in some locations
* For the week of August 6th,  if you haven't already, check fields this week for aphids, especially late-planted fields. Even a quick walk into the field will alert you to a problem. Some places will have low or no aphids, but you may find some surprises.
*  Think coverage, coverage and COVERAGE

Last week I said not to ignore aphids just yet... and sure enough ALL  %*#%*@%   HAS BROKEN LOOSE in the last few days.  Bottom line, aphid numbers in many locations in the eastern great lakes area have come up, including locations in Michigan. I know this message is long, but I wanted to do my best explain and summarize the many observations so you are ready for the upcoming week.

Early last week (July 23-25), a front moved west to east across the Great Lakes. The circulation was counterclockwise, in other words winds moved south to north at the east edge of the front, back to the west, then north to south at the back of the front. If you looked at the radar picture on Tuesday July 24, the spotty rain showers in Michigan were moving north to south in a straight line as the back of the front crossed the state.

As the front moved east, the eastern edge passed over areas (New York and Quebec) heavily infested with SBA. My colleague Michelle Roy in Quebec has had a big SBA infestation this year, and she reports that 90% of the acres have been treated in southwestern Quebec. The front presumably picked up winged aphids, circulated them back to the west and then south, dropping them with rain on the back edge. As a result, fields probably received large number of winged aphids from NY and Quebec that started infestations - sort of like sparks coming off a forest fire.

Below are summaries or quoted parts of messages from colleagues in MI and other states.  All of these messages are from Friday Aug 3rd, obviously a key aphid day.  They illustrate how quickly aphids can infest an area.


SUCTION TRAP COUNTS:  Captures of winged aphids increased dramatically the weeks of July 16 and 23 in the aphid suction trap network ( http://www.ncpmc.org/traps/index.cfm), especially in Minnesota and Wisconsin. There are no traps on the network to the east of MI, but I assume Quebec and New York had big flights too.


Martin Nagelkirk, Sanilac County MICHIGAN:   "...a CPS fieldman and farmer found aphids at threshold along Lake Huron".  Likely fields in neighboring counties are infested too. Insects of many types often rain-out along the edges of the Great Lakes.

Phil Kaatz and myself, Lapeer Co. MICHIGAN: Phil and I found a field with a healthy new infestation on Aug 3, north of Lapeer city. The field was clearly newly colonized - each plants had 2-5 moms (probably sisters deposited by the same winged aphid a week ago), and each mom's tiny new babies.  This field was late-planted, R2 stage, and the aphids were infesting the juicy top part of the plant. An infestation like this can be over threshold in 7-10 days.

Scott at Napolean Feed Mill in Jackson Co MICHIGAN: "I am seeing over threshold numbers of aphids in the Springport, Parma, and west of Jackson area. ...I'm not finding aphids in all fields, but the fields I am finding them in seem to be over threshold."   Remember that there are also reports of potassium deficient fields going over threshold in southern Michigan.

NEW YORK, Keith Waldron, Cornell Univ:  "Over the past 10-14 days SBA populations in Cayuga, Chemung, Columbia, Cortland, Oneida and Seneca counties have increased dramatically with numerous fields exceeding the recommended threshold... some fields treated earlier this season for SBA are again at or over threshold."  Keith reports fields outside these counties are below threshold, but increasing.

Ron Hammond, OHIO STATE:  "NE OH definitely has problems.  Saw numerous fields having reached threshold, few somewhat over threshold, one field where plants were fully covered with aphids and sooty mold and honey already getting heavy.  Haven't seen that since 2005.  Surrounding counties have them on the rise nearing threshold. ...From others around the state, have heard aphids are showing up, but no where near what the NE section of OH has"

Missy Bauer w/ the Andersons, Pioneer OHIO  (just south of Michigan) -  Missy reports numbers near her house have "increased dramatically" in the last two weeks. Her latest count averaged almost 150/plant.

Tracey Baute with OMAFRA in ONTARIO: "I have heard from some key reps today that they have fields that had very low to nearly no aphids last week to 10 days ago, now have aphids above threshold.  In particular an area that has really exploded is in Niagara and Haldimand Counties, close to Buffalo NY.  Some other fields scattered across the province will be sprayed in the next 7 days as the beneficials have lost the battle." 

Tracey also adds an important caution about rebounding aphids and spray COVERAGE:  "We've had some fields sprayed 2 to 3 times with aphid populations rebounding within 10 days..... Spray coverage is probably the biggest issue for these guys now".

Remember the 3 most important things when spraying for aphids = coverage, coverage and COVERAGE!


***A BIG Thank you to everyone who calls or emails me with reports of insect infestations and numbers. The reports help to get a big picture of what is happening****

chris

<><><><><><><><><><><><><><><><><>
Dr. Christina DiFonzo
Field Crops Entomology Program
Michigan State University
East Lansing, MI   48824

Mailing Address: 243 Natural Science Building
Office Address:  331 Natural Science Building

tel:  517-353-5328    fax:  517-353-4354
<><><><><><><><><><><><><><><><><>

 

 

8. Questionnaire that seeks your opinions and views on the topic of pollinators in agriculture.

Greetings Sustainable Agriculture Network Discussion Group:

 

As part of a larger research study, I have developed a questionnaire that seeks your opinions and views on the topic of pollinators in agriculture.  I am gathering information from agricultural producers, land managers and scientists.  I would like to ask you to take a few minutes to participate in the study by completing an online questionnaire that takes 5-10 minutes to complete.  Your answers will be kept confidential and information gathered from the questionnaire will be pooled and not linked to any individuals.  At the completion of the study, results will be available upon your request.  The questionnaire is online at a web-based survey service, SurveyMonkey.com. 

 

To access the questionnaire, please click the following link:

http://www.surveymonkey.com/s.aspx?sm=n9bGeFsu2zxrwZbRAgdDUg_3d_3d

 

If you have any questions, comments or concerns, please feel free to contact me.  Thank you in advance for your assistance! 

 

Best regards, 

Annette Meredith 

 

 

*(************************************************

On 7/30/07, JONATHAN SOLIS <[log in to unmask]> wrote:

> > The South Side Community Coalition is still looking for

> > farmers/vendors to sell their produce/products in the Southwest area

> > of Lansing. This area is in need of fresh fruits and vegetables.

> > Also, we have a high usage of EBT and Project Fresh Coupons clients.

> > We will be accepting EBT (electronic benefit transfer) as well as Project Fresh Coupons.

> >

> > NO FEE TO USE SPACE

> > EVERY TUESDAY 2PM TO 6:30PM

> > SET-UP TIME IS FROM 12:30 TO 2PM

> >

> > Location/Contact Number

> > 2101 West Holmes Rd

> > Lansing Michigan 48910

> > Solis:                517-394-6846 Wk

> >                         517-393-3547 Hm

> > Lisa:                 517-394-3217 Wk