Vol. 5 No. 4 April 25, 1997

Weekly Crop Update

University of Delaware Cooperative Extension

Volume 5, Issue 25

September 18, 1997

Field Crops:

Understanding OptimumŪ High-Oil Corn: Part 3--Advantages and Limitations

Richard W. Taylor, Extension Agronomist


Bob Uniatowski, Extension Associate - Field Crops



Remember from Part 1 that there are two approaches currently being used to create corn with improved oil content. These are conventional plant breeding selecting for improved oil content and the top cross method. Conventional hybrids with improved oil content contain about 5.5 percent oil and have yields about 20 percent lower than conventional (low-oil) hybrids. TC or Top Cross BlendsŪ also referred to as OptimumŪ high-oil corn have 6 to 7.5 percent oil and depending on variety selection can yield close to the conventional (low-oil) hybrids. In these articles when I refer to high-oil corn, I mean those hybrids developed by the top cross method unless otherwise noted.


There are several ways to capture the added value from Optimum high-oil corn. First, a farmer can grow the oil and protein on-farm and use these to replace more expensive off-farm sources. Secondly, a farmer not feeding additional fat on farm can get a 3 to 5 percent increase in animal performance by growing Optimum high-oil corn. A third way to capture the value is to grow the grain and receive a premium for the increase in fat and protein at the time of sale of the grain. Finally, there likely will be an incentive program for those growing Optimum high-oil corn and using specific products on their farm.


Advantages of Optimum High-Oil Corn:


g Each kernel contains a higher energy content.


g The grain has more of the essential amino acids needed for animal growth.


g The grain has increased value as an animal feed.


g Its use results in less dust in the feed and during grinding.


g It reduces the need for fat supplements in feed.


g For swine, dairy, and beef producers, if you do not add fat to your ration, you can get a 3 to 5 percent performance increase using Optimum high-oil corn. (Research documents the oil's availability to swine and poultry. For dairy and beef, less research information is available but in all likelihood it will be useful.)


g The grain parent by not producing pollen will save energy. This energy can be used for grain production.


g Higher commodity prices are available to farmers growing Optimum high-oil corn.


Limitations of Optimum High-Oil Corn:


h If it is planted next to conventional corn, the first 10 to 20 rows may have been contaminated with foreign pollen resulting in a 1 to 2 percentage point reduction in oil content. If the grain is to be sold off-farm as Optimum high-oil corn, you may want to handle these rows differently from the rest of the field.


h One researcher found that in the field the grain may dry more slowly than conventional (low-oil) corn. However, harvested grain dries more rapidly in a drier. Until you have experience with the drying characteristics of Optimum high-oil corn use lower temperatures and monitor it carefully to maintain quality.


h A TC Blend may be more vulnerable to stress at pollination. The jury is out on this question. In a TC Blend, pollination occurs over a 12 to 15 day period versus 5 to 8 days for a standard hybrid. Since only 8 to 10 percent of plants in a field produce pollen, severe stress conditions will be a concern. This can be alleviated by growing Optimum high-oil corn under irrigation.


h There will be additional costs involved. A small premium will be charged for the seed plus most companies will recommend increasing the seeding rate by 8 to 10 percent. To justify and receive a premium, the seed must be stored and handled separate from conventional (low-oil) corn.


h Yield Potential: This really is a question of hybrid selection. In a study conducted at Ohio State University, one could choose a TC Blend that yielded as much as the standard (low-oil) corn hybrids. As in any variety trial, not all TC Blends performed as well as the conventional corn hybrids. When selecting a TC Blend choose the best adapted variety for your area.


A discussion of yield potential can quickly be outdated. This technology is changing so fast that test results more than a year or two old no longer represent today's reality. Improvements in both the male pollinator and the female grain parent are being made each season and these improvements are eliminating much of the yield drag observed with the initial TC Blends. It's still a good idea to take a look at the newest hybrids on your own farm in strip trials so you can evaluate characteristics such as standability and disease and insect resistance before planting large acreage to a new hybrid.


Vegetable Crops:

Availability of Athena Cantaloupe for 1998 -

Ed Kee, Extension Vegetable Crops Specialist



It has come to our attention that any Athena cantaloupe seed left with dealers has been recalled by the basic producer, RogersNK. This is a result from some dissatisfaction with the variety from growers in South Carolina, Georgia, and the bootheel of Missouri. Apparently, certain lots of seed, or certain growing conditions caused a large portion of female flowers, thereby reducing yields. We have not heard any reports on this in Delaware and Maryland, and did not see any evidence of this in the many fields were visited this season. Athena produced well in our Cantaloupe variety trial. We will still be recommending Athena; it has produced well, ships well, and has great flavor.

RogersNK representatives report that while they have recalled existing supplies, 1997 seed production and harvest is in full swing and they expect the variety to be available. They are investigating the reported problem and developing a strategy to keep the variety available. You may want to stay in touch with your supplier of Athena to make sure you can obtain the seed for 1998.



Vegetable Crop Diseases-

Bob Mulrooney, Extension Plant Pathologist



Cabbage, Broccoli, Cauliflower.

To prevent Alternaria leafspot and downy mildew, spray Bravo on a 7-10 day schedule.



Maintain applications of Bravo to prevent black rot and other foliar diseases. Where Phytophthora fruit rot is a problem, add a fixed copper fungicide to the spray.




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Upcoming Meetings...





Ag Computing and Electronics Expo


8:30 a.m. to 6:00 p.m.

December 17, 1997

Holiday Inn, Lancaster - Host


Sponsored by:


Pennsylvania Farmer


in cooperation with:


Nutrient Solutions in Agriculture

Penn State Cooperative Extension

Pennsylvania Farm Bureau


ACE Expo ‘97 features:


h Information - packed seminars.

Speakers include experienced farmers and Ag specialists. Farmers from all fields of agriculture and experience levels will find sessions to help prepare them for business in the 21st century. Look for special program markings designating:


B For beginning computer users. These sessions are geared toward those with little or no experience.


A Advanced. Look for these if you’ve been using computers or have already attended one of the beginner sessions.


P Precision Agriculture. ACE Expo ‘97 offers a special track to show you how to get started with the latest satellite and variable-rate technology.


D Dairy. We’ve dedicated five sessions to show the latest computer applications in Pennsylvania’s biggest Ag industry.


You’ll also find seminars on Internet, financial planning, field crop recordkeeping and mapping, communications, nutrient management, security, fruit, vegetables and beef production!


h A bigger and better trade show. Visit exhibits from companies specializing in agricultural software, hardware and interfacing equipment for barn, field and pickup. With one-half hour between sessions, you’ll have plenty of time to question vendors and comparison-shop!


For More Information Contact the Penn State Cooperative Extension at 717-394-6851.


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Weather Summary

University of Delaware,



Week of September 12 to September 18, 1997




0.03 inches: September 12

Readings taken for the previous 24 hours at 8 a.m.





Ranged from 85 F on September 18 to 80 F on September 12 & 14.



Ranged from 63 F on September 12 & 18 to 54 F on September 16.


Soil Temperature:


70 F. Average for the week.


Compiled & Edited By:

Tracy Wootten

Extension Associate - Vegetable Crops


Cooperative Extension Education in Agriculture and Home Economics, University of Delaware, Delaware State College and the United States Department of Agriculture cooperating, John C. Nye, Dean and Director. Distributed in furtherance of the Acts of Congress of May 8 and June 30, 1914. It is the policy of the Delaware Cooperative Extension System that no person shall be subjected to discrimination on the grounds of race, color, sex, disability, age or national origin.