The Tropical Fruit Forum

I have not read about the relationship between undeveloped seeds and zygotic seeds but it is logical for me because if seeds are nucellar they are all genetically identical and none is genetically weak. So there is no reason why seeds are bigger and smaller or dead except that some contain more nucellar embryonos than others. We will see if my theory is right here. When I remember my other plants the theory seems to be quite plausible.

My Till #1 was not at its best this year. It was better last year and the year before. I can sent you budwood if you want. We have nasty custom restrictions for the USA but all within Europe will be possible, also many other countries.
I am very glad that more and more people are in search of better varieties. We will certainly come to a good end and will greatly support any further breeding by our findings. I began with hardy citrus around 15 years ago. We are now already a great step further.

My second hobby are edible mountain ashes (Sorbus aucuparia). The fruits of the plant were eaten for thausand of years but remaind horribly bitter and weakly poisonous. Then over 100 years ago a young herdsman found a better varitiety (Sorbus aucuparia var. moravica) that was less bitter and had sweeter fruits. And not many years later, the Russians independantly found really tasty varieties that were not bitter and poinsonous at all. But even if we had only gotten S. aucuparia var. moravica we had archieved as real breakthrough because I could proove that it is heterozygous for the bitter agent which is also the poison. S. aucuparia is just an analogy that shows how even a single mutation can change a lot. This as an encourangement for all Poncirus hunters.

My own judgement of the Poncirus from Alan was milder. I compared it to average Poncirus which is way worse. But I agree that it does not please one's tongue.

For the sake of clarity. The Poncirus from Alan that Skandiberg refers to is from seeds that I got 11 years ago. (Custom rules were more liberal at that time.) We could not exactly remember from which place they were, maybe from Athens. I got them as Poncirus seeds and the original fruits looked like Poncirus fruits. I could not taste them at that time because they got very old and largely rotten in the post package.

Today I ate fruits of a sipling of the described tree. It was a surprise. Here my review: Fruits have normal Poncirus size while the first seedling (described by Skandiberg) tends to produce small fruits. Outwardly just normal Poncirus fruits with the typical smell but less parfumed than average Poncirus. Pulp not juicy which is very untypical for Poncirus. I could not press a single drop of juice out of them. But the pulp did not taste dry when I bit on it. It just did not release its juice as freely as Poncirus does. The pulp was also more crispy and rough than normal Poncirus pulp. Seed contend high. Rind thicker than average Poncirus with a thick white part but not extremly thick (~ 5-6mm). The rind was more crumbly / brashly than typical Poncirus rind. The pulp tasted quite mild and significantly less sour than Poncirus pulp, it was almost sweet. Even the rind was edible without real discomfort although I would not call it tasty. There was some resin in the fruits but not excessively. The plant looks just like a normal Poncirus. Influence of the growing conditions upon fruit attributes can be excluded because the tree stands in direct neighbourhood (~3cm) to its sipling, and both trees grow infact through each other. My only explanation for the very special fruits is that this tree is in fact a Poncirus hybrid (F3, F4, F5...?) with probably some pumelo influence in the background. That would explain the pulp texture and the thicker rind with its relatively thick white part. It would also explain the low acid content.

I wait now for the fruits of the third tree. Its fruits are not yet ripe but look very different from the first two trees. They have more lemon shape and a pebbled peel not so common for Poncirus. Perhaps that tree will also show signs of hybrid nature.

I cannot tell anything about the hardiness of the described trees because I have them in a glashouse that I heat when temperature is lowers than a few degrees below freezing. The glashouse has not very much sun but the trees grow well.

Hi Lauta_hibrid,

I can make photos in two days. But the seedlings are still small, except C. ichangensis x Chandler and Poncirus x Chandler (Chandler as the pollen parent).

Chandler is, by the way, a very difficult mother plant. You have to cut off all flowers except the pollinated ones because Chandler dropps all fruitlets from a corymb except the last ones, even when the last ones contain no seeds. And then you get no more than a handful seeds from each fruit. It can be less: one or two. Chandler seems to dislike non-pumelo pollen. Hybrids with Poncirus seem to be impossible. Only pollen of African Shadock x Poncirus led to many seeds - probably because it is half pumelo. But Citrumelo pollen is already difficult. The big fruits let you believe that you have many seeds. You wait very long until they are ripe. and finally you get no seeds or very few. I believed for some years that the low seed production was my fault but I am now conviced that Chandler is just difficult. I used fresh and frozen pollen. I tried many combinations. I took care of the flower position. I cut off all non treated flowers. But always the same result. Chandler is best used as pollen parent.

The leaf form can be interesting. I have some hybrids of Chandler x (African Shadock x Poncirus). Most of them are well growing, some more Ponciruslike most more Citruslike. Most seedlings became monofiliate very soon although they started with trifoliate leaves. Then most seedlings have long and narrow leaves. If I did not know better I would have guessed that I have hybrids with Ichang Papeda before me. My guess is though that the narrow leaves come from African Shadock x Poncirus. When Chandler x Morton has the same feature I will revise my guess.

It was a complex mutation then, was it?

Very convincing picture. I regred that I did not more with my Keraji this year. It had perhaps hundreds of flowers and I pollinated only a few. There is at least hope that the bees crossed it with African Shadock x Poncirus and with Yuzu.

Next year will be a Keraji year!

My impression is that the amount of pollen that Morton produces is dependant on the temperature. The first blossoms in the year have little pollen the last flowers a lot.

I have pollinated a citrumelo (mislabeled thus variety unknown) with Morton. The citrumelo has around 50% zygotic seeds, is very aromatic, good brix but is as it is not edible. The few seedlings from the cross with Morton were more than 50% zygotic and all well growing. I pollinated Chandler with Morton. One fruit was seedless the other is not big and probable also with few seeds as the cross Chandler x C35 was also low seeded. According to my experience Chandler is a pure mother plant. It dislikes pollen other than pumelo pollen (or African Shadock x Poncirus pollen). It also dislikes citrumelo pollen.

I have tried Poncirus x Morton. The seedlings look different but I have no clue whether they are hybrids or not. I have one seedling Ichang Papeda x Morton. It has serious root problems and grows slowly. I grafted it onto Poncirus a few weeks ago.

This year I tried Staraji x Morton. Staraji has good fruit quality but is way too late ripening and also late blooming. I could imagine that hybrids with Morton are eariler blooming when the Poncirus part induces the formation of winter flower buds so that the fruits also ripen earlier. Staraji is self-imcompartible with its own pollen and Morton is seedless when self-polinated. I hope that crosses between Staraji and Morton are also self-incompartible and thus potentially seedless. (I dislike generatively crippled plants that cannot build seeds but like plants that are seedless because of self-incompartibility.)

I would also recommend Changsha x Morton. I did not try it but Changsha x Dunstan Citrumelo and Changsha x Poncirus is easy.

I do not know how suitable Keraji is as mother plant (I had technical problems until recently that made tests difficult.) But it is interesting that Staraji is self-incompartible and zygotic. That means that Keraji is heterozygous for nucellar embryony and perhaps adds recessive genes for the expression of self-incompartibility. In addition, it is the only one of Ilyas hybrids up to now that is sweet. I might therefore be that Keraji passes off sweetness in a better way than other varieties. In my view, hybrids with Keraji are quite interesting for these reasons and also for the peppery peel of Keraji. The peppery peel is to a weaker degree also present in Staraji. (Other varieties: Ichang Papeda, Yuzu, according to literature C. wilsonii).

My Sandford Curafora did not give good fruits for some years because it has not enough sunlight. But the very first seeds were zygotic. So it may also be a good choice as a mother plant for crosses with Morton. Sandford Curafora is late blooming and late ripening. But its fruit grow fast. Hybrids with Morton may produce winter flower buds and have early ripening fruits.

Somebody that wants to cross Morton with Satsuma may also consider crossing it with Kijomi (Satsuma x Sweet Orange). Kijomi is said to be as hardy as Satsuma but it has zygotic seeds. It is also pollen sterile like Satsuma and able of parthenocarpy. Usirius, I have Kijomi. Ask me if you want it.

Is everybody aware of Ilya´s so called "Morton Nucellar"? I did not have fruits so far but from what I have read it is hardier than Morton and has fruits that taste like multi-vitamin juice.

My Starton24 blooms abundantly, is more or less deciduous and probable hardy even under my conditions. Fruits are very small but taste is really good (like sweet orange but sour). A great disadvantage is that it does not produce pollen under my growing conditions. It stands in a green house but I could only obtain pollen once in three years from some late flowers that opened when both nights and days were warm. Seedlings of Starton24 are mainly nucellar. But I got around 20% zygotes. (Pollen donor unknown: A mix of all pollen that I had at that time.) Starton24 tends to yellow leaves in spring, interestingly more on Poncirus than on its own roots while the Poncirus rootstock has green leaves. It is in my view a very interesting hybrid but somewhat genetically unbalanced. I hesitate to recommend it for breeding. Result of own crosses with Staraji and Valentine not before next year.

The so called PT #7 (hybrid 7) is a new Ponciruslike very hardy hybrid with many zygotic seeds and fruits like Poncirus that are less resinuous and less sour than Poncirus. Not great quality fruits but one of its offspring, hybrid #8, has Ponciruslike fruits without any off-flavours and sticky oils. My guess is that PT #7 x Morton can result is extremly hardy hybrids with all desireable fruit qualities. I would prefer, however, if I were you, Usirius, US899 Q/O. It also has zygotic seeds, is very hardy, has a nice mandarine taste and has less sticky substance and less sourness than Poncirus thus indicating that it is most likely heterozygous for both sweetness and sticky oils. So it has all that PT #7 has but has in addition a mandarine taste.

I would not be too excited at the moment. It happens from time to time that seedlings have abnormal leaves, sometimes what you have sometimes three first leaves. It becomes exciting when the next leaves are also weird.

I ate many sour oranges in Sizily. Bitter inside and definitely not like Lemons. Often not much juice. Yet an interesting aroma of its own.
It is commonly held that sour oranges are crosses between a mandarin and pumelo and that lemon is a cross of sour orange (female) and zitron (male). The typical lemon aroma comes from the zitron and perhaps also from the pumelo part of sour oranges. All that is so say that lemons are highly heterozygous. I unfortunatelly haven't experience with citremons but it is very improbable that all Citremons taste similar. Even pure poncirus has from type to type great differences in taste. Poncirus hybrids in general are a wide field from absolutely horrible taste to pretty good taste.

The starting point of our discussion was if somebody has experience with a specific citremon that seems to be extraordinary good. We should take care that we mention the specific citremon we refer to in our taste reviews.

What regards breeding new stuff crosses with kumquat hybrids or yuzu may also be a good idea. I have already crossed limequat with yuzu. Citrumelo crossed with Yuzu exists already. There are some ways to approach the typical lemon taste in combination with hardiness. Sour oranges would not be my favourites as they are not very hardy in my climate and are extremly susceptable to root rod as potted plants. I had to through away all because I did not want to root them all anew after each winter.

I had very great problems with spidermites years ago. I could kill them with a soap solution but as they were in my two greenhouses that was too much work and never complete. I bought predator mites (native in Califormia) but they were to temperature sensitive. I live in zone 7 and my greenhouses are quite cool during winter.

I finially bought native predator mites called "Tyron" mites. They are used in wineyards and fruit plantages in zentral Europe. These mites killed all the spidermites. I got rid of all from January till summer and they never came again as these Tyron mites overwinter in the cold. I bought them in 2021 and have never again had problem with spider mites. From time to time I see a Tyron mite on a leaf. So they are still there. I cannot recommened Tyron enough. It is, however, not so easy to buy them. They sell only big packages for about 70 Euro and deliver only in January. But it is really worth buying them when you have a greenhouse. They tolerate cold, even strong frost. They tolerate dry air and moist air. And they are very effective. And I think the prize is ok when I recall what I had spend for soap solution over the years and for predator mites that are not climate resistant.

The Citrangeremo was grafted on Swingle Citrumelo which in principle does well on my somewhat loamy garden soil. It can be that the air was too moist during winter and some fungus entered the roots.
I have no own experience with the resistance of Citrangeremo roots. I have only read that all Australian species were imune to phytophthora. If that is true Citrangeremo is likely to be quite resistant against root rod when grown on its own roots. I can only tell that Fingerlime seedlings and also their hybrids with Ichang Papeda do well on their own roots. But Fingerlime is not E. glauca and both are not Citrangeremo.