" Anther propagation has also been used for a long period of time."
H.Kuska comment. What is "anther propagation?
I spent a lot of time trying “anther culture” (trying to change tetraploids to diploids). I got as far (callus stage) as anything published at that time. I am not aware of anyone being successful with roses. This what I posted at that time:
Anther Culture Of Roses
Anther culture is a sub area of tissue culture in which one removes the pollen carrying anthers from the unopened flower and places them on tissue culture medium. The individual pollen grains form a callus and then a new plant with half the chromosome number of the parent. I have been attempting anther culture of commercial greenhouse roses (which are tetraploid) with the goal of producing diploid hybrid teas. They would then be crossed with diploid species roses to produce fertile offspring from which one would then select for plants with the flower form of the hybrid teas and disease resistance and winter hardiness of the species.
The following is the summary of the most recent literature paper that I could find on the topic: V. Wissemann, C. Mollers, and F.H. Hellwig, “Microspore and Anther Culture in the Genus Rosa, Investigations and Current Status”, Angew. Bot. 70, 218-2220(1966). “Within the Rosaceae, only very few results of haploid culture are reported. Successful haploid callus formation in Rosa was only mentioned once but unfortunately could never be repeated. Actually no publication is available on the current status of haploid culture in Rosa. In this paper we present recipes used in our research on the origin and evolution of the genomes in the genus Rosa. Published for the first time, microspore culture of isolated microspores clearly shows response to in vitro culture with first divisions in the cells. Anther culture produced calli with at least some of them of partial haploid origin. Both methods can not be said to be established, but results presented here show some direction of further research.” They were not successful in regenerating plants with half the chromosome number from the calli.
Simultaneously with the above workers, I have been trying a number of formulations. One that appears to give acceptable positive callus results (reproducible in five batches) is based on a published formulation for Strawberry anther culture - H.R. Owen and A.R. Miller, Plant Cell Reports,15,905-909,(1966). My version uses (amounts for 20 ml sample) 0.08 g standard MS plus vitamins, 0.01 g L-glutamine, 0.70 g glucose, 0.08 g MES(buffer), 0.10 g gellan gum, 0.01 g Ca ascorbate, 0.0001 g AgNO3, 0.02 g PPM(preservative), 0.00004 g IAA, and 0.00002 g BA. The samples are kept in the dark for 30 days then put under continuous florescent light. I use a 700 watt microwave oven to sterilize (5 minutes with 20 ml sample in center surrounded by 4 containers of water which act as heat sinks). I have a balance which is sensitive to 0.01 g. I used solution dilutions and insulin syringes for the smaller quantities. Small amounts of both DMSO and propylene glycol have worked as solvents to dissolve the organic hormones.
I used as my “Laminar Flow Hood” a commercial HEPA air purifier (retail about $60.00, I paid about $32.00 on sale - Holmes HAP-240) which was mounted in a cut-out in a clear plastic clothing storage container which was set on its side. For pictures of my setup click here.
In two recent - very successful - batches I modified the hormone composition to the following: 0.00002 g IAA, 0.00002 g NAA, 0.00001 g BA, and 0.00002 g 2-4 D.
The above solutions have worked to produce the calli. So far I have not been successful in regenerating plants from the calli. I would be interested in any pre-prints or “personal communications” concerning suggestions as to a procedure to try for the plant regeneration phase. In addition to trying a number of published hormone procedures that worked for other plants, I have also tried a hormone free solution.
