intergeneric cross with watermelon

[terracotta]

inspired by Joseph's intergeneric cross of citrullus lanatus with bryony alba I was thinking of any other species that could accomplish the same function but be less poisonous. anything with a tubers or large root would probably suffice. any thoughts? has anyone done any watermelon breeding between wild relatives?

[raymondo]

I haven't done any breeding but was told by a Dutch vegetable breeder that his company has used Citrullus colocynthis to introduce disease resistance into watermelon. It's a perennial with a fruit a little smaller than a tennis ball. It is supposedly poisonous but I guess they do backcrosses into watermelon to eliminate as much of the unwanted genetics as possible, which would include, I guess, perenniality.

[terracotta]

thanks for the response. Do you know how they breed out the poison? Citrullus colocynthis is a powerful purgative that causes people to vomit blood. bryony alba has sap that makes people break out in blisters like poison ivy and 9 to 12 berries is enough to kill anyone in more than one kind of poison ( don't remember exactly what but there is purgatives, laxatives, those that cause inflammation)
I was thinking of something in the Acanthosicyos genus since people can eat those but seeds are impossible to get. Also growing them out of there natural habitat is very difficult due to the several meter long taproot.
www.az.com.na/tourismus/natur-und-umwelt/the-nara-bush-acanthosicyos-horridus.107620.php
here's some other members of Benincaseae
zipcodezoo.com/Key/Plantae/Benincaseae_Tribe.asp

I might even consider luffa it's perennial and people eat it. if people wait too long then they have a sweet sponge.

[raymondo]

Apr 21, 2012 20:11:38 GMT -5 @terracotta said:

Do you know how they breed out the poison?

Like I said, I think they just backcross. Since they are looking for specific disease resistance, this would be straight forward, though it would take a good number of generations, especially if the disease resistance is recessive.
I see no reason not to do the same with perenniality. Cross them, look at the next generation, if any develop a perennial taproot, backcross to watermelon and repeat. You might have to self for a generation or two to find the taproot again. Eventually though, you'd have pretty much a watermelon but with a perennial taproot. In Australia, C. colocynthis grows in the tropical north. The above ground parts die back during the dry season. I don't know how it would behave in other climate zones.

[terracotta]

Russians did this once and took three generations before it turned red which they said indicated success ( like what joseph said he is doing). they were breeding for salinity resistance. However poison genes are dominant similar. to crossing a hot pepper with a sweet one it will always be hot. I would like someway to test for poison. B. alba smells highly astringent which is one way to detect the poison but that is only one of them. i was thinking of how they breed poison out of almonds but that has to do with spectrograph but that's quite expensive.

[terracotta]

I am thinking of using moon and stars as a indicator cultivar since the spots are a dominant and then can weed out them at the seedling stage.

[Joseph Lofthouse]

Apr 22, 2012 12:22:59 GMT -5 @terracotta said:

However poison genes are dominant similar. to crossing a hot pepper with a sweet one it will always be hot. I would like someway to test for poison. B. alba smells highly astringent which is one way to detect the poison but that is only one of them. i was thinking of how they breed poison out of almonds but that has to do with spectrograph but that's quite expensive.

Dominant genes are easy to eliminate from a breeding program. With a large enough population, in the F2 generation all undesired dominant genes can be culled if the plants are selfed. Recessive genes are the plant breeders balm: So easy to stabilize.

I expect that the B. alba poison could be isolated by a suitable extraction technique followed by paper chromatography. Very inexpensive techniques. I'm going for the even lower cost and faster method... The taste test: My body has been tuned by eons of ancestors to be able to easily detect poisons. I could taste several thousand fruits one after another before approaching the lethal limit. And then do it all over again the next day.

[terracotta]

Apr 22, 2012 0:17:24 GMT -5 raymondo said:

I see no reason not to do the same with perenniality. Cross them, look at the next generation, if any develop a perennial taproot, backcross to watermelon and repeat. You might have to self for a generation or two to find the taproot again. Eventually though, you'd have pretty much a watermelon but with a perennial taproot. In Australia, C. colocynthis grows in the tropical north. The above ground parts die back during the dry season. I don't know how it would behave in other climate zones.

They can survive in 40 degree F temps and have a strong root system that resists quite a bit from environmental to disease. if you want to try this remember it breeds readily with domestic types, the fruit is mainly seeds and the main economic uses is oil and as mothball substitute to kill insects .

www.jatrophaworld.org/citrullus_colocynthis_88.html
www.tootoo.com/s-ps/citrullus-colocynthis-seeds--p-3410617.html