Good Morning Everyone, A friend of mine has posted this query on another site and not received a response to answer his question fully. He is wanting to know about creating hibiscus with higher chromosome numbers and to then use these in a hybridizing program. Specifically with the species Schizopetalus (he is also wanting someone to send him seed of Schizopetalus - it is quite hard to come by). His query and a type of response are as follows:

You may recall a while ago I posted about wanting H. schizopetalus

seeds to use in making tetraploids with Surflan A.S..

I have a few questions. The method described in a previous post's

link says to submerse the seedling in the 1:100 or 1:200 dilution of

Surflan for 24 hours. Hibiscus which are sensitive to even being

overwatered will surely die after 24 hours in even distilled water

much less any other solution mixture. How do you get past that? Also,

a theoretical question. If after the H. Schizopetalus are tetraploid

and years later if they produce viable tetraploid seeds and you did

this process again with the seedlings would you produce octoploids or

will that not work? Since many tropical Hibs have chromosome pairs in

the three digits, doubling the tetraploids to octoploids would allow

H. schizo. to fertilize an even greater number of larger flowered,

higher chromosome numbered hibs right?

Any thoughts?

Also........ ..I am still looking for pure H. Schizopetalus seeds !

ART

Hello Art, Using Surflan to induce polyploidy in Hibiscus sounds down right risky to me under home owner conditions especialy maybe in a lab for tissue culture (very sterile).I was using Surflan 20 years ago as a preemergent Herbicide in a Wholesale Landscape Nursery over the top of our plants @1to2 tablespoons in 1gal of water over 1,000 sq ft of pots or ground area but the label specified waiting 2weeks after repoting liners 2 1/4" inch pots into 6''inch pots to apply it Suflan and rinsing it off the foliage and into soil within 8 to 12 hours with 1" of overhead irrigation water I think. The reason for the 2 week wait was severe if not permenant stunting of poorly rooted new plants.Thats what I would call a several day old hibiscus seedling. We also couldn't use it at all on Liriope or lilly turf even when well rooted it was stunted.

I'd be more inclined to try Colchicine as a mutigen just don't give yourself cancer with it. Or hey surely you must know someone who works at NASA Cape Canaveral you live so close. The Optimara African Violet Company sent African Violet seed into space they came up with the hardier better growing and blooming Everfloris Violets from those seed they grew after interstellar irradiation these are probably Tetraploids. Also I have witnessed Yoder Bros. Crysanthemum Cuttings being immersed in a aquarium of water then bombarded with Radiation on a Partical accelerater Cyclotron to produce Color Mutations at a Local Cancer treatment Center. The water was nessesary to simulate Human Body density so the cuttings were not cooked. My second Job at the time was supervising the cleaning of a large Radiology and Radiation Therapy Groups Building nights and weekends. The Engineers that maintained the Medical Radiation treatment eqipment did this Plant work on weekends. There are stories the Hibiscus (Coloring Book's) Seed, was Irradiated this way prior to its germination. most of they other seed failed to germinate.

But Hey, I maybe all wet in my previous opinion about Surflan? They use 2-4-d herbicide in tiny amounts to aid fruit set on Citrus.

Ps try Writing the Agricultural Attache of the US Embasies in South Eastern African Countries or Madagasgar for Nursery Sources of H.Schizopetalis Seed. A friend of mine used this Info method for Staghorn Platycerium Fern Sources and habitat climate Info, but he may have gotten results as he was a retired US Forestry Scientist.

Thanks for any advice.

Cheers, Brian Kerr.