Re: hybridization vs. genetic engineering

At 07:31 AM 7/22/97 +0600, you wrote:
>I keep getting asked about genetic engineering and really don't have a good
>answer, would you please help?
>Are hybrid varieties of seeds genetically engineered?
>When Michelle Miller talked about reduced synthetic chemical use, she said
>using disease resistant varieties--are these naturally occurring or
>genetically engineered?
>Using "old varities" of seeds, crop rotations, no-til or minimum till is it
>possible to get the same yields as with hybrid varities--in corn, for example?
>I hope that I am not the proverbial "can of worms," I would like to be able
>to answer the negativism I encounter with something other than "I really
>can't answer that question."  
>Karen Mundy
>Rural Economic Analysis Program
>Dept. of Ag. and Applied Econ
>Va. Tech
>Blacksburg, VA 24061-0401
>(540) 231-9443

There is a good reason why you are confused. 
In a sense genetic engineering and hybridization both accomplish the same
thing - they both result in new genetic types.  
The difference is in how they acccomplish this.  

Hybrids come from seeds that are developed by cross-pollinating specific
parental types so that the next generation will be a very uniform crop with
hybrid vigor.  Hybrid vigor is typically observed in outcrossing species
(grasses and grains for example) when two very different inbred lines are
cross pollinated.  The hybrid gets half of its genes from each parent.

Genetic engineering usually refers to biotechnological methods that can be
used to insert a very small piece of genetic material (DNA) so that the
resulting plants can be nearly identical to the parent, except for the gene
or genes that were inserted.

Nowadays, some hybrids may have genes that are artificially inserted, using
high tech biotechnology methods.   But, generally speaking, hybrids are not
genetically engineered, that is , not using high-tech or biotechnology.  
In some sense though, plant breeders have been genetically engineering crops
for hundreds of years, because they have been using traditional
hybridization (cross pollination) techniques to obtain new (recombinant) types.

I hope this explanation is helpful.  

Dr. Rae Schnapp