MemberTom,

From what I've read on the subject, Maize x Tripsacum is very easy if you carefully remove the husks, shorten the silks to about 1.5 inches, pollinate with Tripsacum pollen, then wrap the ears with paper while the seeds develop.

The problem in the cross is that Tripsacum pollen doesn't have enough "stuff" to grow pollen tubes the full length of the Maize ear. Shortening the silks solves this problem.

I sure don't want to put you off the experiment, but other results indicate that the best way to breed Tripsacum traits (such as pest resistance) into Maize is by first crossing Tripsacum with Zea diploperennis, then crossing these hybrids onto Maize.

But there's no harm in trying Maize x Tripsacum directly. I had planned to cross Z. diploperennis with an ornamental Maize with colored and striped leaves, hoping for a colorful perenniel Zea. I didn't know what a wild and sprawling plant Z. dip. is. It's like giant crabgrass. Interesting, though.

Karl

Actually, I've heard instances that there has been a hybrid of Maize X Eastern Gamagrass, and in every article it points out all the labor, patience, and dedication to create this type of cross. It didn't specify if they rescued it from an embryo, or that it came from seed. From what I remember, the hybrids were very similar to Maize, with very little traits of the Gamma parent. It told that the success was achieved using some of the native american dent corn races, and that a cross with the sweet corn was impossible. I know I have it archived somewhere on my computer. You may want to investigate Native Seed Search and purchase a few seeds there if you are attempting the cross. I'm working with the Zea diploperrenis and Eastern Gamma Grass, and when I have an inbreed line-- then I'll start hybridizing it with corn to exploit the perrenial genes.

Enrique

Enrique,

Zea and Tripsacum have very different chromosome arrangements. When they are crossed, we can't expect anything like "mendelian" segregation because corresponding genes aren't lined up together. The chromosomes of the hybrids crossover at heterochromatic regions without regards to homology.

Sorry about the jargon. Chromosomes have some "sticky" places called heterochromatin. Homology refers to the similarity of the nucleotide sequences in the DNA. Ordinarily crossovers form where similar sequences of DNA are lined up. But in very distant crosses, like between Zea and Tripsacum, things aren't so neat. In crosses of Zea and Tripsacum, blocks of Tripsacum genes are inserted into the Zea chromosome strucure.

I have also read reports that discuss the difficulties involved. But I've seen a picture of an ear of corn thoroughly pollinated by Tripsacum. The seeds are smaller than normal, but viable.

Read Paul Mangelsdorf's book, 'Corn: its origin, evolution, and improvement' for more details.

And search for information on Tripsacorn, which was bred by one of Mangelsdorf's students, Mary Eubanks.

http://www.agron.missouri.edu/mnl/74/100eubanks.html
http://www.gmprc.ksu.edu/kernels/rk_oct_00.html

Karl

Enrique,
I second Karl's suggestion.
If you can get a copy of Mangelsdorf's book, you'll love it.
That was where my maize x tripsacum ideas started.
And the MNL (Maize News Letter?) site is one of my old favorites. There's alot of other good information in addition to the Mary Eubanks stuff.
Karl,
Do you know where I can get seeds of Zea diploperennis? I used to have some, but I'm sure they're inviable by now, since I haven't grown them for ~10 yrs. I grew the annual teosinte, two years back, and did some crossing with popcorn and podcorn. But unfortunately, didn't get a chance to plant any of the hybrid seed this past season. Maybe this coming season...
Tom

I can spare a small amount of seed of Zea diploperennis. I have a plant growing in the garden now, but I'm going to keep the majority of my seeds just in case "something" happens. They are viable, and I got them from Australia. I had so much trouble getting them here in the US germplasm site. Mike Millard soppose to have them, but I couldn't get a hold of him by phone, mail, or email. Contact me when you like.

I got my seeds from John L. Hudson, Seedsman, 10 or 12 years ago. I see that the company is now

REDWOOD CITY SEED COMPANY
P. O. Box 361, Redwood City, California 94064 U.S.A.
Craig & Sue Dremann, Proprietors
PHONE: (650) 325-7333

http://www.ecoseeds.com/

They even have Hopi Turquoise corn.

I don't see Z. diploperennis on the webpage, but they do have Zea mexicana.

Karl King

Here is a link that might be useful: Redwood City Seed Company

It's an interesting coincidence that I too was recently thinking about this topic. I see that some of you have managed to find more information on the topic than I have managed. Are any of you interested in trying this experiment this year? Even if we get some sterile hybrids, if the trees are Winter hardy and produce a better fruit then we can still propogate through cuttings, bud chipping, in vitro tissue culturing which is pretty much what they're already doing with pawpaw cultivars.
As for how to manage this, I am checking with my local botanical conservatory to find out if they have any annona specimens. If they do, then I've already made tentative inquiries about "renting" some flowers on those trees to attempt some cross-pollinations. I'm fairly certain that I have at least one contact who can supply me with pawpaw trees for pollination. It may even be possible to "rent" a few of his trees for back pollination.
Anyone else have a chance to go through the literature on hybridization attempts? I'll try to get to Ohio State University and check their holding this week or next. I'm just not sure how to look it up as yet.

Fragraria vesca, alpine strawberry is a natural polyploid either hexa or octoploid I do not remember. The cross with tetraploid vars was achieved by at least Marionnet (France) with one (or more) smaller fruited better flavoured var released.

Interspecific hybrids are very easy to get in some plant families such as Orchids, Aquilegias or Cacti. Among the later a lot of hybrids were and are raised from the very varied and dissimilar Echinopsis, Trichocereus, Lobivia, Aporocactus, Borzycactus, Akersia, Cleistocactus, Hildewintera, Matucanas, Sulcorebutias, Shrensias, Acanthocalycium, Oreocereus, Pilosocereus, Epostoas, Trixanthocereus, Denmoza, Erdisia.
Echinopsis x Epicactus hybrids have long ago been published and denied but now with Aporocactus we have a sure bridge with Epicacti and a considerable lot of Hylocereeae and Rhipsalideae.
All cactus interspecific hybrids I grow are fertile!

Then we have to consider that species and generas are man made classes with initially suposed intersterility. Life is more complex than this.

Friendly yours
Pierre Rutten

Very interesting thread, and mostly about plants I know nothing about. But Karl mentioned the example of sinningia x rechsteineria (had to look up the correct spelling). Before these genera were combined into sinningia the hybrids were called "x gloxinera", which was in reference to their similarity to Florist Gloxinia hybrids. Sinningia is a fascinating genus with over 65 species in cultivation, and lots of us, busy making crosses. Last year about ten new species were brought into cultivation, so I guess the total number is more like 75. Ironically, the only known species not in cultivation or rediscovered in the wild is the type species for the genus, S. helleri. Sinningia hybrids can vary from highly fertile to sterile. Now, there are new intergenerics with sinningia, but like rechsteineria, the other genera are possibly destined to be moved into sinningia. The two genera I am thinking of are paliavana and vanhouttea. The genus leitzi, with big interesting flowers has already been turned into a sinningia (S. brasiliensis). I am including a great web site which has photos of all the Brazilian gesneriads including just about all the known sinningia, Paliavana, vanhouttea and nematanthus (another of may favorite genera). There are also photos of Brazilian plants in other families.

There are quite a few intergeneric hybrids in gesneriads. Mostly crosses have been made with various genera that make scaly rhizomes. Until fairly recently we all thought that there were two groups of these types that crossed with each other but not with the other group. But, now some crosses between the two groups have been made, and they vary from real dogs to crosses with lots of potential. One group is achimenes, eucadonia, smithiantha, nyphaea, and the other group is gloxinia, kohleria, koelikeria, and a few other minor genera.

There is also lots of talk about the potential of crossing African violets with their closest relatives in the genus streptocarpella (streptocarpus, subgenus streptocarpella).

There are also other intergeneric lines of breeding in gesneriads including ones that produce fertile hybrids.

for the serious breeder the U.S. GOVERNMENT has a free gene bank their websight is a bit hard to work. at www.ars-grin

by the way that was www.ars-grin.gov for hard to find germplasm and seeds from the U.S. government free of charge but you must evaluate them for the government. what is this tripsacum ? and where can I get diploid sugarcane seed?

Interspecific hybrids are very easy to get in some plant families such as Orchids, Aquilegias or Cacti. Among the later a lot of hybrids were and are raised from the very varied and dissimilar Echinopsis, Trichocereus, Lobivia, Aporocactus, Borzycactus, Akersia, Cleistocactus, Hildewintera, Matucanas, Sulcorebutias, Shrensias, Acanthocalycium, Oreocereus, Pilosocereus, Epostoas, Trixanthocereus, Denmoza, Erdisia.
Echinopsis x Epicactus hybrids have long ago been published and denied but now with Aporocactus we have a sure bridge with Epicacti and a considerable lot of Hylocereeae and Rhipsalideae.
All cactus interspecific hybrids I grow are fertile!

---------------------------------------------------------

For a really weird intergeneric hybrid look here..

http://web.tiscali.it/no-redirect-tiscali/Echinopsis/eimpollinazione.htm

This is Hylocereus hundatus x Trichocereus "Blüte wie Wüstenglut"
, an epiphitic jungle cactus crossed with a terrestrial cactus. A few (rare) hybrid epiphyllums also have some echinopsis in their background.

So, Geoffrey_1, whatever happened? Was anybody able to cross Asimina triloba and Cherimoya? I am very interested to know.

(My email link is not working so just post any responses this forum.)

I found an old intergeneric hybrid raised by Ivan Michurin that has finally been introduced to the West: x Sorbocrataegus 'Ivan's Belle'. It came from a cross of a Mountain Ash and a Hawthorn.

Pictures can be seen at:
http://www.clivesimms.com/new_page_20%20Ivans%20Belle.htm

Karl

I tried to study the genetic background of Duchesnea indica. It seems that it is a cross of the diploid F. nilgerrensis with an unkwnown tetraploid Potentilla with a chromosome doubling. So it contains two genes of F. nilgerrensis and and four equal Potentilla genes. So the most successful way would be to cross Duchesnea indica with F. nilgerrensis, but F. nilgerrensis is tasteless and not very interesting. The diploid F. nilgerrensis crosses also with F. vesca but not very good. This leads me to the conclusion that it would be worth to cross Duchesnea indica with diploid F. vesca or decaploid F. x vescana. As in crossings between Fragaria and Potentilla Fragaria should be used as female parent.

It is possible to cross diploid Fragaria vesca with pollen hexaploid F. moschata. So I concluded that it should also be possible to cross decaploid F. x vescana (contains F. vesca genes) with pollen of F. moschata. I pollinated some flowers and got 400 seeds. The germination was between 80-90 %, but most plants died the following weeks or month. Only 5 % survived. Some are dwarfs. From the remaining I think only 4 plants are intersting. Till now the didn't bloom but hopefully next year. My idea is to cross this octaploid plants with normal garden strawberries.

Japanese plums and apricots can be crossed successfully. This was first done by Luther burbank. Studying the literature it seems also possible to cross diploid apricots with the hexaploid European plums (P. domestica). I pollinated several flowers this year and hope to get two seeds. Did anyone do these crossings?

The following is from an article that appeared in the 1960 Canadian Rose Annual pages 69-70. Of interest are the several crosses of roses with other members of the Rosaceae family. Although the crosses at that time were sterile, it is possible that with modern techniques such as chromosone doubling fertile plants could be made.

Title: Hybridizing Limitations
by Roy E. Shepherd, Medina, Ohio
"The writer has succeeded in budding a rose on to an apple branch and in crossing a rose with a member of the blackberry family, but the bud remained dormant and the seeds did not germinate. Dr. J. H. Nicolas, formerly Research Director for Jackson and Perkins, was more successful as he raised three seedlings of a cross between an apple and a rose. They were similar to the latter in general appearance but showed evidence of apple influence in the bark, foliage, and in the peculiarly colored double apple-like blossoms. The latter, incidentally, were somewhat similar to those produced by Bechtels Crab but not as well formed or as large. The plants were barely remontant and after blooming they were inactive until fall when a second spurt took place. Further experience with Rose x Apple and Rose x Hawthorn crosses gave similar results and all proved to be sterile. They were therefore valueless for use as parents in further breeding along this line."

keking wrote:
The only Peach-Cherry hybrids I've read about involved the Western Sand Cherry, Prunus besseyi, which is actually a plum.

P. besseyi is in the Prunus section microcerisus, along with P. tomentosa (Nanking cherry) and some other such fruits. These are not properly plums nor cherries. Rather, since they are not so long seperated from plums by taxonomists, they have not been given differnt common names. But microcerisus seems to be a more primative branch of the Prunus genus, and the easiest to cross with.

Concerning Maize x Tripsacum and the reciprical, I have worked with them while working at the Land Institute. The project was dropped when a mutant Tripsicum was found with higher yeild, and the crossing with maize was dropped. Then another group started working with the Tripsicum and my group dropped it in favor of milo x Johnsongrass.
Maize x Tripsacum has given seeds which don't absolutely require embryo rescue, but the seeds have so little endosperm that the embryoes generally don't have the energy to get above the soil, or even get through the seed coat. But germinating the seeds and peeling them, or peeling them first, then setting the embryo on soil will get a few started. Starting them on sterile nutrient solution does work better.
Tranfer of genes from Tripsicum to maize worked best for Drs. harlan and De Wet. They were lucky to cross maize with a tetraploid apomictic Tripsicum. In the hybrid, the maize chromosomes reproduced sexually and the tripsicum chromosomes reproduced asexually. So repeated pollinations with maize pollen continually made plants with the same origional chromosome number, but with traits of the new pollen parent in each generation. After several generations, this started breaking down and diploid maize with tripsicum traits was recovered.
My group found that the F1 Maize x Tripsacum plants were perennial but not by themselves. They would keep growing taller, never going dormant nor putting out a rhizome. They would have lived forever, maybe, if we had kept digging them up every 6 months, and replanting them deeper, and kept them worm in the winter.. They grew out of the ground!
This was true of plants with 2 sets of domestic maize chromosomes and 1 set of Tripsicum chromosomes and plants with 1 set of domestic maize chromosomes, 1 set of Z. diploperennis chromosomes, and 1 set of Tripsicum dactyloides chromosomes.
T. dactyloides is the most winter hardy of the Tripsicums. Most others are tropical.
We got the seeds of the above from Dr. Galinat.
Crosses between Maize x Tripsacum work best if a South American popcorn, or a cornbelt dent is used. Worst if sweet corn is used.
Dr. Galinat wa not able to get a cross between Z diploperennis with tripsicum. But Z. diploperennis would set seeds when crossed with an amphiploid of domestic maize X T. dactyloides.
This is at least pertly because corn has what are called Ga genes. Ga+ will cross with Ga+ and Ga. Ga- will cross with Ga- and Ga. These are genes that determine pollen growth in the silks. Ga stands for Gamete, or gametophyte, I forget. Anyway, Tripsicum has Ga+, and South American popcorns have Ga+. Commercial cornbelt dent corn has Ga, and will cross with about any corn. Sweet corns are mostly (all?) Ga-. most others are unknown, at least to me.

Sinningia x Rechsteineria lumping together was done by Dr. Carl Clayberg, or at least it was based on his research. I was blessed to be his student in a hortacultual plant breeding course, and he was on my grad committee.

Ultraeco. HI.
I can answer 2 of your questions. "what is this tripsacum ? and where can I get diploid sugarcane seed?"

Tripsicum is a genus with n=18 (maize is n=10)that is distributed from Maine to Argintina. Some species cross, not easily with maize, with maize. Tripsicum dactyloides is a native prairy grass from Maine to Florida, west to Knasas and Nebraska, and south, some say all the way to Argintina. I personally doubt this species goes from Maine to the tropics, crosses the tropics ond goes back to temperate regions. Rather I think that similar species are being confused with each other. But whateveer.
I have both the normal and the mutant mentioned earlier. The normal has what looks like corn tassels with just a few female flowers at the bottom of the tassel, the rest male flowers. The mutant has female flowers all or almost all the way to the tip, giving about 25 times as much seed.
Tripsicum dactyloides is a very vigorous grass, producing an excellent forage for cattle, and as many tons dry matter per acre as corn silage.
If the tripsicum x maize hybrid is an amphiploid, it is quite female fertile, setting much seed with pollen from either parent species. But the hybrids are cytoplasmicly male sterile. If the origional cross was made with Tripsicum as the female, one may keep crossing with maize pollen, and get pure maize but it will be male sterile, and no restorer is known. The same is true with the opposite crosses.
So let me know if you want seeds or plants of T. dactyloides. They produce seeds more in the spring and one must use a very early maize or grow the maize in the greenhouse to make the cross. Or sometimes the Tripsicum will put up a few bloom stalks throughout the sumemr, but not always.
Seeds should be ready soon. Plants would have to be sent in spring or fall, I think.

The answer to the question about diploid sugarcane seed is much shorter. There isn't any. The lowest known sugarcane is octaploid. And it goes up to 12 ploid and beyond.
The closest to a diploid sugarcande would be sweet sorghum. They both have n=10, and they cross both ways. Hybrids are usually somewhat fertile. Sugarcane, unlike Sorghum, is very tolerant of aneuploidy, or irregular chromosome numbers. And sugarcane will cross with an amazing number of othe grasses, including Zea, Miscanthus, Sorghum, and many others.
And depending on which sugarcane speices is used, the seeds from crosses can have all the maternal chromosomes and half the paternal chromosomes. Nifty. It makes it easier to get a good cultivar to aquire new genes for disease or insect resistance.
Walter

I pollinated female strawberry flowers with mixed pollen of raspberry, blackberry and tayberry but I didn't got any seed.

I made the following crossings this year:
1. Duchesnea indica x Fragaria vescana 'Rebecka'
2. Fragaria vescana 'Rebecka' x Duchesnea indica
From the first I got only one single seed that also could be a selfed Duchesnea indica. From the second I got good seed set. I will post here whether the seed germinates.

Title: STUDIES ON THE INTERGENERIC HYBRIDIZATION BETWEEN APPLE AND PEAR

Authors: SHIN Y U; KIM W C; MOON J Y

Authors affiliation: HORTICULTURAL EXP STN, RDA, SUWON, KOREA.

Published in: Research Reports of the Rural Development Administration (Suweon)volumn 31(2 HORTIC), pages 9-14, (1989).
Abstract: "It was attempted to overcome incongruity between apple and pear with aid of compatible mentor pollen in order to obtain the materials for intergeneric hybrids. Fruit set in apple/pear cross was 6.6% and 84 seeds were obtained from 21 fruits (mean seed number per fruit: 4.0). In pear/apple cross, fruit set was 16.5% and 415 seeds were obtained from 230 fruits (mean seed number per fruit: 1.8). Fruit and seed set was significantly lower than those in apple/apple or pear/pear crosses. Germination rate of seeds were 74.6% in apple/pear, and 88.0 in pear/apple crosses, but more than half of the total germinated seeds died within 6 months after germination. We can obtain 13 seedlings from apple/pear cross and 51 seedlings from pear/apple cross. Leaf morphological characters were classified as mid-parent type, apple type or pear type. Peroxidase zymograms of the hybrid seedlings by polyacrylamide gel electrophoresis were different in band numbers and locations compared to their parental species."

I scanned Burbank's discussion of his Strawberry x Raspberry hybrids, along with a picture.

Karl

Walter Pickett wrote, "Maize x Tripsacum has given seeds which don't absolutely require embryo rescue, but the seeds have so little endosperm that the embryoes generally don't have the energy to get above the soil, or even get through the seed coat. But germinating the seeds and peeling them, or peeling them first, then setting the embryo on soil will get a few started. Starting them on sterile nutrient solution does work better."

A mixture of maize and Tripsacum can give better results. MxT kernels growing adjacent to MxM kernels are larger than those growing next to other MxT kernels. I have seen a picture showing this effect, but don't have it handy.

Karl

Hi all. I'm not as smart as any of you (or anybody else anywhere, really), and I also don't know exactly what gets to count as a 'genus'. But amonst gesneriads, intergeneric crosses are quite common, though like someone else mentioned, they are often infertile or not very fertile (producing verrrry little seed and only on rare occasion).

The genus is defined by taxonomists, but the precise definition varies. The "rule" that intergeneric hybrids have to be sterile is as pointless as the older rule that interspecific hybrids have to be sterile. Some are, some aren't.

It often happens that almost-sterile hybrids produce fertile offspring that combine characteristics of both parents, even if they are from different genera.

Orchids are even more willing to produce intergeneric hybrids than gesneriads, some cultivars carrying the "genes" of 4 or more genera.

Karl

Mentor pollen mentioned by Shin, etal. in Henry's post is often found to be useful in making difficult crosses. For one thing, germinating pollen stimulates other pollen grains to germinate. So, foreign pollen that would not germinate on its own may be stimulated into growth by the native (compatible) pollen.

In addition, multiple pollination has been found to increase seed and fruit set in apples, pears and plums. The "theory" here is that the first batch of pollen damages the style tissue as the pollen tubes bore their way through it. The second batch then has an easier time of it, and even incompatible pollen tubes may be able to run the gauntlet and fertilze ova.

The attached item is from Pollen and Pollination Experiments. II. The influence of the first pollination on the effectiveness of the second one in apple by T. Visser and J. J. Verhaegh in Euphytica 29 (1980) 385-390.

Karl

"It was found earlier that repeated pollination by hand or by bees increased fruit and/or seed set of apple, pear and plum (KONDRAT'EF et a!., 1972; PANOV & PETKOV, 1975). Our data confirm this with respect to apple. It appeared that pollinating twice at an interval of one or two days, on average doubled the seed set per pollinated flower as compared with pollinating once (Table 1). As normally fruits with sufficient seeds only are retained on the tree, it is understandable that a second pollination would improve fruit set by adding to the number of fertilized egg cells of the flower. However, a new element of the present study is that, with the aid of 'marker pollen', the second pollen was shown to be on average twice as effective as the pollen applied first (Table 4). That is to say, against every three seeds formed by a single pollination, a double one produced six seeds, of which two resulted from the first and four from the second pollen. Hence, the second pollen, besides fertilizing extra egg cells, contributed to seed set by partly outmanoeuvring the first pollen (for 1 in 3 egg cells, see also Table 5).

This is neither attributable to a difference in pollen quantity, which was on average the same for both, nor to a difference in stigma receptiveness between the first and second application, as postponing a single pollination by the same interval had no effect.

A simple explanation is that the first pollen promotes the efficiency of the second. Presumably this happens in connection with pollen tube growth. On the basis of data from KNIGHT (1917), COOPER (1928), MODLIBOWSKA (1945) and WILLIAMS & MAYER (1977) it may be assumed that after one or two days tubes of the first pollen have travelled well into the style and/or have entered the ovary. These pollen tubes, according to KNIGHT (1917), make their way through the stylar tissue along a more or less well defined path which is accompagnied by the decomposition of cells, or extrusion of material from them. Apparently, the tubes of the second pollen are able to travel faster along the path' prepared by those of the first and so arrive at the same point in the style in a shorter period. As the tubes of both use up and diffuse substances at the same rate this means that the second pollen tubes have a greater reserve for subsequent growth than the relatively exhausted tubes of the first. The former tubes (of the second pollen') are thus able to transverse the intervening distance to the egg cell quicker than the latter, explaining the dominant role of the second pollen in seed set.

In sofar two kinds of equally viable (and compatible) pollen may be assumed to perform similarly when applied as a mixture, it appears probable that in a double pollination the first pollen functions as it does because it is applied in advance. For this reason it may be called 'pioneer pollen'. Its action evidently differs from that of 'recognition' or 'mentor' pollen which, in order to overcome incompatibility, is applied simultaneously (mixed) with incompatible pollen and is either killed or irradiated beforehand. With respect to incompatibility, it would be interesting to know whether there would be a difference between pioneer and mentor pollen -- advance versus simultaneous application -- and between untreated or irradiated pollen and killed pollen -- germinating versus unviable pollen."

REFERENCES

COOPER, J. R.. 1928. The behaviour of pollen tubes in self and cross pollination. Proc. Amer. Soc. Hort. Sci. 25: 138-140.

KNIGHT, L. I., 1917. Physiological aspects of self-sterility in apple. Proc. Amer. Soc. Hort. Sci. 14: 101-105.

KONDRAT'EV, V. D., L. I. LEVITSKAYA & E. M. KOTOMAN, 1972. The output and quality of plum and apple hybrid progeny from supplementary pollination. Biologiya i Biokhimiya Plodovykhi Vinograda Ki- shinev, Moldavian SSR ' Stiinca: 169-195 (Hort. Abstr. 44 (1974) 9269).

MODLIBOWSKA, IRENA, 1945. Pollen tube growth and embryo-sac development in apples and pears. J. Pomology 21: 57-89.

PANOV, V. & V. PETKOV, 1975. The effectiveness of pear pollination by bees. Gradinarska i Lozarska Nauka 12 (1): 33-40 (Hort. Abstr. 45 (1975) 8188).

VISSER, T. & J. J. VERHAEGH, 1980. Pollen and pollination experiments. I. The contribution of stray pollen to the seed set of depetalled, hand-pollinated flowers of apple. Euphytica 29: 379-383..

WILLIAMS. R. R. & MARIA MAIER. 1977 Pseudo compatibility of the apple Coxs Orange Pippin. J. Hort. Sci. 52: 475-483.

Mentor pollen has also been used successfully in blueberries:

Wenslaff, T.M., and P.M. Lyrene. 2000. The use of mentor pollen to facilitate wide hybridization in blueberry. HortScience 35:114-115.

Walter Pickett wrote:

"P. besseyi is in the Prunus section microcerisus, along with P. tomentosa (Nanking cherry) and some other such fruits. These are not properly plums nor cherries. Rather, since they are not so long seperated from plums by taxonomists, they have not been given differnt common names. But microcerisus seems to be a more primative branch of the Prunus genus, and the easiest to cross with."

Walter,

Do you know of any hybrids of P. besseyi or tomentosa with "proper" cherries? The information I have (all pretty old) is that P. besseyi crosses so readily with plums that -- from the breeder's point of view -- it could be regarded as an "honorary" plum. Hansen did a good deal of work with the species (Hansen's Bush Cherries) and its hybrids with plums. Gurney's on-line catalog currently lists Oka. I don't know whether their paper catalog still has Sapa, Kaga and the rest.

These all interested me a great deal when I lived in Kansas, but here in California their extreme hardiness is not so necessary. Still, they are fascinating and potentially useful for the reduced size of the plants.

Karl

Right. From the breeder's point of veiw, P. besseyi and diploid plums are as one.
And the information below sugests that from a breeder's veiw, P. tomentosa and sweet cherries might be as one.
And P. besseyi and P. tomentosa are as one.
St. Lawrence Nursery's catalog, which is online, lists Montmorency cherry, a quality pie or sour cherry, as P. tomentosa x sweet cherry. Montmorency is much hardier than other most cultivated sour cherries. And a lot hardier than any sweet cherry. I'll bet a backcross would give interesting cherries, and some would retain some of the winter hardiness of P. tomentosa. And be fertile.
I have ordered it.
If this can cross with the P. bessyi x P. salicina hybrids, it might make some tasty fruit. It would bring together Japanese plums and sweet cherries, as well as the P. besseyi and P. tomentosa, which wouldn't help the flavor.
Not that they are bad, but just not exceptional, like some Japanese plums and certainly sweet cherries.
P. besseyi isn't a very good "plum" or "cherry" either. But it blooms late here.
Depending on the year, it can be P. besseyi hybrids or no plums at all.
I have thought of P. besseyi x apricot. There is sometimes a 6-week difference in the bloom date between P. besseyi and apricot.
There is so much that could be done in genus Prunus.

Some info I gathered a while back has crosses of P. tomentosa with P. avium and P. cerasus. I don't have a source for that, though. One day I was left for hours at the library to kill time waiting for a ride, so I decided to make a big table and scour the literature and see what Prunus crossed with what. I've regretted ever since not citing each thing on it, because I find myself constantly referencing it. This represents a few hours work, so it's full of holes in all likelihood, but here's what it I have for...

P. besseyi x:

americana (fertile)
armeniaca (sterile)
cerasifera (fertile)
davidiana (sterile)
persica (sterile)
simonii (fertile)

P. tomentosa x:
avium (fertile)
cerasus (fertile)
persica (sterile)

If it's important to some one I'll see if I can dig around and find the references...I still have copies of some of the papers and I know a couple of books I got a lot of the info from.

By the way, I'm always glad for additions to this table, if any one has any.

By the way...I don't have the paper itself on hand, but if I remember right I believe the mentor pollen in the blueberry paper was not killed or irradiated before hand, but came from a parent with a readily discernable phenotype so the resulting seedlings could be sorted out and discarded. Its role was to encourage healthy fruit development to allow seeds to mature properly.

Okay...a correction to that last post. I thought as I was typing it that an impressive number of those were fertile. I misread my own notation on the table. The "sterile" ones were indeed marked sterile, but the symbol I took for "fertile" actually meant "cross successful, fertility unknown".

Also, just for the sake of completeness, I also have that a cross was attempted between P. besseyi and P. hortulana, and did not successfully generate any seed.

Sorry to get anyone's hopes up.

Looks like Walter snuck a post in while I was working on mine...(both of them)

I'd be willing to bet St. Lawrence Nursery has their facts wrong...'Montmorency' is straight P. cerasus. I've heard Amy Iezzoni, cherry breeder from Michigan State, refer to it as such on more than one occasion, and I'm willing to take her word on it.

Just out of curiousity, do you have a reference for the besseyi x salicina cross (or is it yours?)? (I'm going to mark it on my table, and I'd like to try to keep track of cites this time...)

Elakazal,

Michurin reported pollinating a peach by P. besseyi. The "hybrid" looked like an ordinary peach but was remarkably hardy. Possibly a partial hybrid.

I have a paper on Hansen's hybrids which I'll try to find and scan. Maybe tomorrow.

I like Walter's idea of crossing P. besseyi with an apricot. Or maybe a plumcot.

BTW. I bought some pluots recently. They were past their prime and rather insipid. Firmer flesh than most plums but with no real flavor. There should be more plumcot-derivatives available soon. Some are quite good.

Karl

I scanned Hansen's paper from the International Conference on Flower and Fruit Sterility.

Karl

Dave's Garden lists some more intergeneric hybrids. Scroll down to the Xs.

Chilopsis (Desert willow) and Catalpa
X Chitalpa tashkentensis 'Morning Cloud'
X Chitalpa tashkentensis 'Pink Dawn'

Cupressus macrocarpa x Chamaecyparis nootkatensis
X Cupressocyparis leylandii
X Cupressocyparis leylandii 'Castlewellan Gold'
X Cupressocyparis leylandii 'Contorta'
X Cupressocyparis leylandii 'Golconda'
X Cupressocyparis leylandii 'Gold Nugget'
X Cupressocyparis leylandii 'Gold Rider'
X Cupressocyparis leylandii 'Naylor's Blue'
X Cupressocyparis leylandii 'Robinson's Gold'
X Cupressocyparis leylandii 'Silver Dust'

Cupressus lusitanica x Chamaecyparis nootkatensis
X Cupressocyparis ovensii

Fatsia and Hedera
X Fatshedera lizei 'Media-Picta'

Gaulteria (Wintergreen) and Pernettya
X Gaulnettya wisleyensis 'Wisley Pearl'

Cistus salviifolius x Halimium umbellatum
X Halimiocistus sahucii

Heuchera (coralbells) and Tiarella (foam flower)
X Heucherella 'Burnished Bronze'
X Heucherella 'Chocolate Lace'
X Heucherella 'Crimson Clouds'
X Heucherella 'Kimono'
X Heucherella 'Quicksilver'
X Heucherella 'Sunspot'
X Heucherella tiarelloides 'Viking Ship'

Mahonia and Berberis
X Mahoberberis aquisargentii

Goldenrod (Solidago) and Aster. Originated in the Leonard Lille Nursery located in Lyon, France (1910)
X Solidaster luteus
X Solidaster luteus 'Lemore'

X Sycoparrotia semidecidua
An intergeneric hybrid between Sycopsis and Parrotia (for F.W. Parrot, 18th century German naturalist)

Karl

Just wanted to add my 2 cents. I have one of the Gurney's Oka Plum Hybrids (mentioned earlier in this topic), that I just planted a few months ago. I also have a Santa Rosa Plum (planted about a week earlier). Based on my research, they should pollinate each other.

I have no idea what to expect, as this is my first cherry-plum hybrid, but based on everything I've heard, I have high expectations.

According to Hansen, 'Oka' was a second generation seedling from a cross of Prunus besseyi x P. triflora, and appeared to be roughly 3/4 sand cherry and 1/4 plum. It should cross easily enough with 'Santa Rosa' (P. salicina), which is partially self-fertile.

Karl

A few years back some splitters went to work on the genus Chrysanthemum. C. japonica was moved to a new genus, "Nipponanthemum. But as some of us know, Luther Burbank used this species in breeding his Shasta Daisies. So, thanks to the magic of taxonomic splitting, Shasta Daisies are now intergeneric hybrids. [Silly!] "

Heaven forbid new technology and a better understanding of science change taxonomic thinking from the dark ages of Linneaus.

Advances are fine, if they are advances. Too often they are matters of opinion.

The fact that hybrids are possible and sometimes fertile has been accepted as reason enough to unite the species of two genera. This happened following the hybridization of Sinningia and Reichsteineria species. But it does strike me as odd to split a genus long after hybrids of the affected species had become popular garden plants.

Should Shasta Daisies be reclassified officially to indicate their intergeneric status?

We should recall that "genus" has no fixed meaning. It is not carved in DNA. It is a human invention that may be useful for identification of organisms but gets to be a problem when various authors apply differing interpretations to keep the names changing.

Besides, "official" name changes are sometimes ignored, which seems to be a good idea in this case.

Some Crosses eventhough their were successful, they produced a low fruit set. An interesting Hybrid was Sorbusxpyrus a cross between mountain ash and pears also known as "Shipova".
The growers of Shipova know that it takes so many years before it bears... and when it does their might not bear heavily... Uncommon fruits for every garden... mentioned that. It's self-fertile, but maybe there's a pollinator out there... sorbus or pyrus species that could improve the fruit set.

Bass

Hi,

I've spent hours researching native plant x foreign plant inter-specific and inter-generic hybrids online, via conversation, etc. I am an amateur horticulturist with an interest in native edible plants. Please help me finish off a reduction of a plant collection I have been working on - I'll explain:

I am interested in growing native plum species and in doing open-pollination breeding and cross-breeding of these exclusively NATIVE Prunus spp. I am not at all interested in controlled breeding of these and just happy to discover what will result of their natural, open-pollinated hybridization.

P. americana
P. angustifolia
P. besseyi (P. pumila var. depressa - eastern subsp.)
P. alleghaniensis
P. hortulana
P. maritima
P. nigra

If I were to plant the following non-native Prunus spp. in the vicinity of the above species of plums, would natural, open-pollination occur?

P. armeniaca (apricot) (I guess so, since Asian plums can hybridize freely? with apricot, then I guess so could native plums? since native and Asian plums are genetically compatible)

P. cerasus (sour cherry) (I think I read P. besseyi x P. cerasus is possible, but I don't know if this is true or could be done without human intervention)

P. domestica (hexapl. - so I don't think so)

P. persica (peach/nectarine - var. nucipersica) (since P. besseyi x P. persica can be done, as known - I'd like to know if this can be done naturally, without human intervention, which I doubt since, as above mentioned, the bloom periods are not closely synchronized)

Obviously, I will not be planting P. tomentosa or other Asian plums that would absolutely freely hybridize with native plums (P. americana; P. besseyi; P. nigra; etc.)

I hope someone who knows the answer wouldn't mind helping me answer this question - and if so, then I will briefly ask the same sort of question regarding native strawberries and find out why it is that native persimmon (Diospyros virginiana) doesn't seem to naturally hybridize with D. lotus or D. kaki (Japanese persimmon), even though they are all 90-chromosomes; hybrids have been formed, but only in the laboratory as far as I have learned.

THANKS!

Steve

I found some persimmon hybrids, from Diospyros virginiana x kaki.

http://www.ediblelandscaping.com/plants.php?func=view&id=201
Rosseyanka
A truly amazing marriage between Asian and American Persimmons (D. virginiana x kaki). Combining traits of both parents. Now the taste of Kaki persimmons can be enjoyed in the North. More of the American parent is evident in leaf but fruit tastes like a soft Asian persimmon.Orange leaf color in the fall. Fruit size is similar to the Asian persimmon. Must be soft to eat. Height 15'-20'. Space 15' circle Zones 5-8. $30.00

http://www.onegreenworld.com//index.php?cPath=1_49
Nikitas Gift
A second generation hybrid of American and Asian Persimmon, Nikita's Gift bears bountiful crops of flattish, 2-1/2" diameter, reddish-orange fruit. These attractive persimmons are very sweet and flavorful. Along with the fruit, you will also enjoy the strikingly beautiful, orange-yellow fall foliage. Nikita's Gift has been tested to minus 10°F in Indiana.
1438 $32.95

Karl

P. besseyi is not pumila var. depressa but is rather pumila var. besseyi or the western sand cherry. Sand cherries are odd anyhow-- until 1990, and still to this day, they are either placed under plums or cherries depending on the guide... After 1990 most place them with the plums. pre-1929 they were mostly classified as cherries.

P. besseyi and sour cherries were reported at the turn of the 1900's (1906 or so) and the resulting cross was called the montebesseyi cherry.

The article you want is;

Mendelian Inheritance in Prunus Hybrids

http://books.google.com/books?id=HvgRAAAAYAAJ&pg=PA214&lpg=PA214&dq=monte+besseyi+cherry&source=bl&ots=2hs707JaEQ&sig=6Zks_ggEwoWJ5EM5Birsw1oYO7g#v=onepage&q&f=false

By 1919 many horticulturist of the time indicated the cross between sand cherry and sour cherry was an inaccurate report though and as an example for the need of increased accuracy in breeding reports.

P. besseyi, however easily crosses (without human intervention) with P. Avium and has been universally reported that the resulting offspring, when fertile, have short lifespans and very dwarf growth habit. The resulting offspring, though fertile, will not cross pollinate with each other.

P. fruticosa and P. cerasus hybrids ave been successful created the result is known as P.X kerrasis (One of the successful named cultivars is known as carmine's jewel) and this hybrid currently is filling the nitch that a sandcherry/cherry hybrid would fill.

The link below lists some of the Prinus crosses that N.E. Hansen created over a period of 31 years;

http://www.bulbnrose.org/Heredity/Hansen/Hansen_hybrids.html

The article linked below reports on F2 seedlings from the Montbesseyi (Prunus besseyi x P. cerasus 'Montmorency')

Karl

I just found another paper in the USDA Yearbook for 1937 that deals with Nanking Cherries (Prunus tomentosa) crossed with real cherries, as well as with P. besseyi. Now I'm wondering whether it might be possible to combine qualities of plums and cherries using the two bush cherries as intermediates.
Karl

This was a very interesting article to track through the years. It never came back around to the original question about asimina x annona. Has anyone had any experience with this?

I have tried several times to find information on hybrids between Asimina and Annona, but have found nothing. On the other hand, I have learned more about the pawpaw than I knew before. For one thing, there are several species of Asimina that fall into two groups: those with maroon flowers that smell "yeasty" or fermented, which are pollinated by beetles; and those with sweet scented white flowers. Apparently only A. triloba has fruit favored by humans.

It should be possible to stir up some variability by crossing A. triloba with its relatives, but one would probably achieve useful results more quickly by crossing among selected cultivars. Here's a list:

http://www.pawpaw.kysu.edu/pawpaw/cvsrc98.htm

Further information on Asimina triloba and its hybrids:

Bowden, WM Chromosome numbers in the Annonaceae. Am. Jour. Bot. 35: 337-381. 1948
Zimmerman, GA Hybrids of the American pawpaw. Jour. Hered. 32: 83-91. 1941 [Notes on A. triloba and interspecific hybrids.]

On the other hand, breeding subtropical Annona for increased hardiness is more likely to result from crossing with species and races found in the mountains, rather than with Asimina. Annona purpurea has been recommended.

"The success of anona culture in Florida through the production of hybrids by Simmonds, Wester, and others, the quickness with which the trees recover when injured by frost, and the delicious character of the fruits make the introduction of the soncoya (Annona purpurea, No. 43426) from Guatemala of peculiar interest. This tree, already in cultivation in Guatemala, produces fruit the size of a pummelo, with orange-colored flesh and an aroma resembling that of our native papaw (Asimina triloba). It can hardly fail to contribute valuable characters to the hybrid fruits which are evidently coming when the plant breeders really get to work in a comprehensive way on the genus Annona."

Years ago I read of relatively hardy papayas (Carica spp.) found in mountainous regions. Many species from the Andes and other mountains are much hardier than their low-altitude relatives. E.g., the Rhodophialas are hardier than the closely allied Hippeastrums; and Hippeastrum vittatum (Andean) is hardier than H. calyptratum (lowland jungles).

Likewise, the "European" or "Persian" peach (descended from species native to Chinese mountains) is hardier than the Peen-To and Honey types that originated in the warmer valleys.

Karl

George A. Zimmerman undertook an 18-year project to breed
pawpaw, attempting to produce intergeneric hybrids by crossing Sugar Apple (Annona
squamosa) and atemoya (A. squamosa x A. reticulata) with Pawpaw (Asimina
triloba). He was unsuccessful. But he did successfully create interspecific
hybrids by crossing Asimina obovata, A. longifolia, and Asimina reticulata with
Asimina tribola. The A. triloba x A. obovata hybrids appeared fertile.
Unfortunately, Zimmerman died in 1941 before his other crosses matured.

Pawpaw
Variety Development: A History and Future Prospects, R. Neal Peterson,
Horttechnology, July-September 2003