Massive Leaf Parsley

Last year I tried to do a bit more wide plant breeding.  I have a few things I am trying that may or may not be worth doing, but it is fun learning.  I seem to be achieving a few things that people say are impossible, as well as other things that it appears that have never been attempted.

One thing I attempted to do was cross members of the Apiaceae family.  Crossing Apiaceae is fiddly and time consuming at the best of times.  So my success rate is low and my confidence levels that I have made the cross I had hoped for is even lower.

Then I grew the most remarkable plant.

My mystery seedling

I attempted to cross skirret and parsley.  I had many hundreds of parsley seeds germinate, as well as many skirret seeds.  As well as those seedlings a mystery seedling grew.

When it was tiny it looked a lot like skirret but something was different.  I like skirret, and I like plants that grow from seed by themselves, so I decided to leave it to grow.  Who knows, it could turn out to be something special?

After the plant grew larger, the leaves looked different from skirret.  It didn't look like anything else I am growing either.  The leaves kind of looked a bit like parsley. But not flat leaf parsley, and not curly leaf parsley.  Each leaflet had rounded lobes.

mystery plant - possibly skirret x parsley hybrid

Skirret and parsley are both in the Apiaceae family so crossing is not entirely out of the question.  Skirret is Sium sisarum, while parsley is Petroselinum crispum.  Wide crosses between different genus is very uncommon, but not always impossible. 

There is very little information on skirret on the internet so it is not surprising that I can not find any reference to any skirret hybrids at all.  It is too bad, skirret deserves to be grown more and understood better.

I found reference to a few parsley x celery hybrids and a parsley x carrot hybrid that was achieved using protoplast fusion.  I read one study where parsley and celeriac were cross pollinated, only  three seeds out of 1,000 were hybrids and the others were not. 

It appears that some hybrids within Apiaceae are possible, but very unlikely.  So it is a good thing I planted (and accidentally dropped) so many seeds!

Parsley leaves at top and middle, skirret leaves lower

The leaves of my mystery plant do not look like parsley or skirret leaves.  The mystery plant's leaves have rounded lobes, while parsley tend to have pointy lobes.  Skirret leaves tend to show a bit of diversity and can be pointy or rounded.  The mystery plant's leaves each grew five leaflets, each of which were about the size of the palm of my hand.  I am not yet certain, but this is either a hybrid, or a remarkable massive leaf parsley.

As it started to flower the leaflets became more pointed and thinner, eventually resembling fatter flat leaf parsley leaves. 

The leaves taste and smell like parsley

The leaf petioles of skirret tend to be almost round in cross section, while the petioles of parsley often are not.  Most parsley tends to have crescent moon like shape in cross section, like a tiny version of celery.  That being said, I do have a few parsley plants with petioles that are almost round.  The leaf petioles of my mystery plant are almost round, resembling skirret petioles.

My skirret often grows a small leaf from the where the base of a larger leaf  joins the plant.  This mystery plant is also demonstrating this behaviour.  Oddly enough, some of my parsley do this while most others don't.  This small leaf became a growing point that eventually put up up flowers.

The base of each leaf became a growing point that eventually sent up flowers

Some of my skirret have purple petioles while others have green.  I don't know if this is due to environmental factors or if it is purely genetic.  Parsley has green or white petioles. The mystery plant has green petioles.

I have not dug up the plant so do not know what the roots look like.  I am very tempted to dig and have a look, but fear that will not end well for my little plant.

The leaves are fascinating

Skirret is a perennial plant that flowers in its first year when grown from seed and goes dormant over winter.  Most parsley is biennial only flowering in its second year, after which it dies.  If parsley flowers in its first year it tends to be due to stress, and the plant is small and weak.  Parsley does not go dormant over winter in my climate.

My mystery plant is currently flowering in its first year.  The flowers are small and unremarkable, much like the flowers on any Apiaceae, but closely resembling parsley flowers more than skirret flowers.  Both my skirret and my parsley are flowering at the same time too.  I do not know if my mystery plant will die after flowering, if it survives I don't know if it will go dormant over winter.

It is widely documented that in parsley is diploid and 2n = 22.  Bell (1966) states that skirret is diploid and 2n = 22, which would mean that a hybrid between the two could possibly be fertile and may be able to set viable seed.

Unfortunately, several other sources contain conflicting information and state that in skirret is diploid and 2n = 20.  If this is the case then this hybrid will likely be sterile and none of its seeds will be viable.  I have no way to determine ploidy levels at home, so will have to wait and see what happens.  

At this stage the seeds appear to be forming normally, so I would be surprised if they are not viable.

Parsley usually reaches about 2 to 3 feet tall.  Look at the size of this monster!

At this stage it was 157 cm tall, it got much taller than this

If this plant is an intergeneric skirret x parsley hybrid, it will be the first one to have ever been grown and should be resistant to almost every disease that bothers parsley.  If this plant is just parsley, then it is the most remarkable parsley I have seen.

This plant may be fertile and produce viable seeds, or it may be infertile and none of the seeds will germinate.  This plant may be perennial and produce offsets like skirret, or it may be annual and die after flowering.  If it is infertile and annual then this will be possibly the first and only intergeneric skirret hybrid to ever be grown. 

Hopefully this plant proves to be fertile and I can save viable seed.  I would really love to grow the F2 seeds and see what they are like.  Hybrid or not, I would love to stabilise a massive leaf parsley.

I can hardly wait to see what happens.  I plan to write another blog post after the seeds have been planted and I know more.