From

Location

Message

Date Posted

Brisbane Australia

For those of you who grow tall corn and produce seed for future crops, how many plants do you put down? I have been lucky enough to be gifted some tall corn seeds from a member here and because of where I live I will need to maintain my own seed stocks. I am concerned with inbreeding depression which can become apparent in only a few generations. Any information would be much appreciated.

1/21/2014 8:40:12 PM

Bethlehem CT

Hi Stillman, I just looked up inbreeding depression and found out you are correct, corn will be messed up quickly by inbreeding. The site I found suggests planting at least 200 plants and saving seed from at least 100 ears. This will keep enough genetic diversity in a line of open pollinated corn. Here is the site: http://www.seedsave.org/issi/904/experienced.html

1/22/2014 7:58:07 AM

Bethlehem CT

Maybe inbreeding depression is why I never seem to have any luck with certain tall corn strains that I have tried.

1/22/2014 7:59:50 AM

Brisbane Australia

Its a shame as I do not have the space to grow 200 corn, I have a few landraces so my best bet may be to plant these different cultivars in the same beds and rely on hybrid vigour I think much of inbreeding depression should be avoided if seeds are kept from numerous good quality plants. However eventually I think it will be necessary to outsource for new genetic variation. Its interesting stuff.

1/22/2014 3:19:46 PM

Piqua, Ohio

plant two varieties thirty in. apart, cut the tassels off one variety, keep the ear's of the plants with no tassel, and you'll know it's not self pollinated.

1/22/2014 5:49:50 PM

Owensboro, Ky.

sorta what Josh, said...bag it and tag it...no cross pollination, means No(or at least, less) cross pollination. Save pollen & put in bag on top of one ear!!! When it's ready!!! Same thing has been done w/ AG's for years...or is that ears? Peace, Wayne

1/23/2014 3:06:59 AM

Brisbane Australia

I'll definitlely be hand pollinating some corn this year, from this I will take corn from as many ears as I can. I am familiar with pedigree and genetics as I studied them at University what I was not aware of was corns rapid inbreeding depression. Anyone who grows it should take the time and have a quick google, these plants are not ideal "pedigree" species, genetic variance is lost much quicker then say AGs or tomatoes. I don't think its too much of a concern for these old landrace cultivars but its worth noting. Its a concern for me as I only have A very limited supply of seed in come cases 4 seeds, so what I will attempt to do is ensure outcrossing of each plant collect a varied amount of seed from numerous heads and interplant with another cultivar with similar growth/maturing time.. have the perfect bed for it. Unfortunately I have ages to wait as we are heading into autumn. Thanks for the input guys its much appreciated. Does anyone have a grow diary with some pics of tall corn growing for me to have a look through to see how they were trellised etc?

1/23/2014 2:54:23 PM

Springfield, Missouri

Although I do not grow tall corn I may have an answer to your question. My professor here at school is a part of the GEM project. GEM stands for the Germplasm Enhancement of Maize. The project is headed by Iowa State University, and their goal is to actively find new varieties of corn from South and Central America and breed it back to commercial hybrids. Through this effort they hope to find novel genes that can be used for industrial purposes or in agriculture to minimize crop loss due to pathogens, ect.

I had the privilege of going to Iowa State University my sophomore year to take a look at this project. They had many, many different varieties of corn ranging from completely inbreed to plants that are out crossed with teosinte. I believe they said it takes 7-9 generations for them to produce an inbred line. Many of these inbred lines only reach heights of 3 to 4 feet. The teosinte hybrids (F1) or the back crosses(BC1) were exceptionally tall. Heterosis is the key to tall corn in my opinion.

The hard part is acquiring seeds, and getting pollen at the proper time. Teosinte and many other tropical corn species are day length sensitive. Structs must be built in order to shade these plants at appropriate times during their development to induce pollen formation.

TLDR: Anyone with the ability to find and cross distantly related varieties of corn, or to stabilize a (corn x teosinte)x corn back cross so that the progeny are not photosensitive will be a very competitive grower, and their seeds will be in high demand.

This is quite possibly more work than anyone wants/or is capable of doing, but I hope the information helps you with your future breeding programs.

1/23/2014 6:12:16 PM

Bethlehem CT

Pretty interesting stuff here.

1/23/2014 8:39:14 PM

Brisbane Australia

I have teosinte seed here. It only grows about 4 feet tall and does not form ears really. I can mess around and try some crosses, can you link me some papers? or maybe email me a little more info? Very interesting, my climate is ideal for this sort of gig as our winters are extremely mild so seed production has the ripen. I'll have to sow some teosinte seeds and try and hand pollinate. my email is
epazotegardens@gmail.com.

1/24/2014 6:52:57 AM

Brisbane Australia

Interesting read pretty much what we have discussed above but worth a quick look. http://www.motherearthnews.com/organic-gardening/landrace-plant-purity-zbcz1306.aspx

2/26/2014 12:45:10 AM

Brisbane Australia

http://garden.lofthouse.com/adaptivar-landrace.phtml

2/26/2014 12:47:28 AM

Springfield, Missouri

Thank you those were great reads!

2/26/2014 2:01:30 AM