29 December 2013

Green Mountain Potato Onion Seedling progress

Last autumn I planted my seed of Kelly Winterton's potato onions. Kelly developed a huge potato onion from a variety that he had been growing for a number of years. When it started flowering, he collected seed, grew it out, and got a lot of diversity, but some of these were enormous, a great discovery since most potato onions are quite small. It's worth reading his online info, which I've linked.

My Green Mountain F1 plants are showing lots of diversity.
Some plants are just growing big onions, and aren't showing any sign of dividing or flowering.

Others have one or two divisions

Some have divided multiple times
And one very strange one has divided 5 or 6 times, and each division is now in the process of dividing again, giving what looks like 28 or so individual stalks, with a crazy Medusa-like tangle of leaves and stalks.

I'm hoping I get some Green Mountain-like big spud onions, but this multiple-bunching characteristic could be useful. Will need to see how it develops over summer.

Another plus from this batch is that a few of them are setting flower buds, giving the possibility of even more diversity - if they set seed and I can get them to grow.

05 December 2013

Harvesting and selecting yellow snow peas

This spring I've grown out a couple of selections of F4 yellow snow peas. I should probably go through the development of these lines, if only to remind myself of what went on.

These were originally grown as a bit of an afterthought along a marginal dry bed next to a half shaded fence. I had returned from a lengthy winter holiday to find a mass of F1 plants with set pods, but because of weather conditions, some of the pods had sprouted or sprouting seeds in them. I just chucked a whole heap of what I thought were ruined seeds into a bed, and got a great germination.

The plants struggled, many only setting one or two weak pods, so selection was a bit difficult, but a few plants stood out, with big pods, and vigour. I bulk collected the yellows, and individually bagged the good plants, and grew them out in March 2013, along with 2 seeds from each of the rest of the yellows. This was not a great strategy - autumn weather didn't give me the great seed crops I had got the year before, and I was away on another extended break, and wasn't around to do a proper assessment. Luckly a friend collected and bagged the seeds for me.

This spring 2013, I sowed seed from some of the offspring of the best F2 plants as well as a couple of seeds from all the other yellows. This has given me a lot of plants to choose from, including some unlikely and subtle variations in the phenotypes.

So how to go about selecting from this big pool of candidates? I certainly don't have room to grow out another mass planting, and I'm probably far enough along the generation pipeline for some of the characteristics to begin to show some stability.

Since these plants are being grown to eat, flavour is a major factor. But I didn't select the parents based on their outstanding flavour - I rushed in, and just crossed everything with everything else, just to get started. A bit less haste might have been a good thing. So the flavour of these crosses isn't remarkable, just standard snowpea. Anything with chalky or dry-mouth feel is rejected. Which still leaves a large number of individuals to select from.

I've begun to think along commercial lines - what would reduce labour costs for someone growing yellow snow peas? In the first place, coloured snows are useful for anyone hand harvesting since the peas stand out from the foliage. But there is another characteristic which makes them stand out - literally.
Medium sized peduncle on my Tall Yellow Snow F4 growouts
The peduncle is the stalk that attaches the flower and pod to the stem of the branch. If these are long, the pods are held away from the foliage, making detection of the pods easier. And double flowering at each node also make the task of gathering pods easier, so if I could find plants with long peduncles and/or double flowering, this would be a useful characteristic.
 The pics also show the light weight aluminium tags I use to label plants and crossed flowers - the embossing lasts even if the ink fades.
The background mesh is 10 centimetre squares

As luck would have it, there was considerable variation in peduncle length, from about 1 centimetre long, to almost 10 centimetres.  Unfortunately there weren't any double flowers in the main F4 crop, but there were some in my F2 growouts of another line, my Golden Spring project which I wrote about in one of my recent posts. But the Golden Spring lines went in late, and there was no opportunity to cross the two yellow snow lines together to combine characteristics. Next season.

The double flowered characteristic showed up  on some of my purple snow growouts - you can also see how the purple pods really stand out from the green of the foliage.

25 October 2013

Contemplating new pea crosses

tMy target yellow snow pea is a dwarf, double flowered, powdery mildew-resistant, sweet, big-podded pea.
My F4 plants of Tall Yellow Snow, a cross between Golden Podded and what I think was Yakumo, are just producing their first pods. But they aren't double flowered, nor disease resistant.

But one of my purple snow pea crosses Delta Louisa X Chamber of Death produced a double flowered green podded F2 that was tall, highly disease resistant, and with huge pods. I'm growing some of F3s of this plant just to see what happens - it was such an outstanding plant last year that I had to grow it out, even tho it was never going to produce coloured pods. Of the twelve of so F3 plants I'm growing, four are dwarfs. If they produce big pods, they might be likely candidates for a cross to the Tall Yellow Snows.

This would make a good cross since the two genes for powdery mildew resistance are both recessive, and the two multi-flower genes (doesn't matter which one I get) are also recessive, as are all the dwarfing genes - again, it doesn't really matter which ones I get.

I'm also wondering which way to do the cross - the usual plan is to do a cross so that the F1 plants show if the cross was successful. For example, when crossing a tall (dominant) to a dwarf (recessive), put the tall pollen on the dwarf flower, and if the cross pollination was successful, the F1 plants will be tall since the F1s should be heterozygous for tall. If however the F1s are dwarf, this indicates that the cross was not successful, and the dwarf plant has pollinated itself in the normal way. This is useful since it saves you from growing out unsuccessful crosses for two generations, (the population starts segregating in the F2 generation).

However there is the issue of maternal cytoplasmic DNA. This resides in the mitochondria and chloroplasts, the power machinery of the cell, rather than in the nucleus, and is only passed down in the maternal line. So if you are after robustness, then using the robust plant as the mother makes sense - it might be connected with the cytoplasmic genetic material so it's a good way of hedging your bets.

So today I'll be out in the vege gardens, looking for flowers that are just at the right stage of maturity.

06 October 2013

A community breeding project - the Golden Spring growout

Cooperative breeding
I’ve got too many lines of peas to explore- -the flurry of crosses I did when I first realised I could cross peas resulted in about 30 or 40 seeds to grow into F1 plants. But these F1 plants produce hundreds of F2 seed, across 5 or 6 various lines – too many to grow. I just selected a couple of the lines to grow out, and have been sitting on these bags of F2 seed, that hold some interesting genetic potential, with no space to explore them.

A correspondent (Damien) answered one of my whinging complaints by offering to grow some for me. Preposterous! My precious F2 seed? No way…

But I gave it some more thought, pondered, then cautiously asked for volunteers on the garden forum I frequent, Ozgrow, to help with one of the F2 lines, Golden Spring, a cross between Golden Podded and Oregon Spring. So AllyH, Raymondo, Aussiejumbo and Damien are now on board as F2 growout-ers. Get sowing folks.

As alike as two peas in pod – not.

I’ve posted before about the smart way to choose female and male parents when performing a cross between two varieties with one parent dominant and the other recessive in a particular gene, so you can check the certainty of a real cross in the F1 generation, instead of having to wait until the phenotypes start expressing in the F2 generation.

But what if the phenotype doesn’t exhibit classic dominant/recessive inheritance? A couple of weeks ago I found just such an occurrence that helped me sort out a mix up in one of my F1 pea crosses.

I want to introduce the hypertendril/semi-leafless trait into snow peas. This trait is widely used in field peas, where trellising isn’t an option. These plants develop extra tendrils, which grow together, and in dwarf or semidwarf peas helps them to knit together into a self-supporting tangle that reduces lodging (falling over). In the home garden this will minimize the need for trellising –  andanything that reduces maintenance is a good thing. Semi-leafless is a recessive trait, so I crossed male pollen from Delta Louisa into the female flower of Kaspa the field pea. But when I grew the F1 seeds out, two of the six or so seedlings were hypertendril. Strange.
Hypertendril on right, normal on left

My  only explanation is that the Kaspa flower had just started to shed pollen when I crossed it, so a couple of the ovaries in that pod must have selfed with Kaspa pollen.

A further bit of evidence was the leaf margins. Kaspa has toothed edges to the leaves, Delta Louisa is smooth. The two hypertendril “F1”s (that weren’t) had toothed leaves, but the other F1s (the real deal) had slightly toothed edges. This suggested toothed leaf edges exhibits intermediate inheritance, a trait that helped me sort out this mixed up cross in the F1.

Toothed margin on right, slightly toothed on left


But I am growing out the two hypertendril F1s, just to see…

19 August 2013

A potato onion update

In autumn I sowed some of the precious Green Mountain potato onion seed I got from Kelly Winterton. Some went in the garden before I left on holidays, but I hedged my bets and put 5 in a pot and took it to my mum's for safekeeping over winter.
The garden grown ones are lost - I either forgot to label them, or the labels have come out. I will be keeping a close eye on the multiplying onion plot, which is where I suspect they are lurking, but I just potted up the 5 advanced overwinter plants to grow on in the hothouse, and sowed the rest of Kelly's seed, around 30 seeds. Here's hoping.

Another late winter update - The Coloured Pea Project selection strategies

While I was away on leave, I had Craig, a grad student of mine, come in and assess the autumn pea growout, and collect pods from any coloured peas to dry down. Returned to find lots of paper lunch bags all neatly labelled and drying in the shed, but it smelled a bit musty, so all the bags came in and were dried off for a couple of days in the oven set to 'defrost'.

Production was poor - we had a cold wet winter for Bendigo, and I think the Powdery Mildew might have shortened the lives of many plants.

But I got lots of very promising lines to explore.

Last autumn I went through my purple podded project growouts, which essentially came from three crossed lines

Delta Louisa X Purple Podded - target = a semi-dwarf semi-resistant snow
Tall Purple-flowered Mammoth X Purple Podded - target = a tall non resistant big podded snow
Chamber of Death X Purple Podded - target = a highly resistant semi-dwarf snow

I was also looking at developing a better yellow snow, by crossing Golden Podded with my Purple Flowered Mammoth.

(There were a number of other crosses - a generic sugar snap X Purple Podded, Golden Podded X Purple Podded, and a few other random crosses because I could).
The F2 grow outs from last spring yielded a number of promising lines, half purple snows, full purple big podded non-snows, disease resistant half purple dwarf snows, disease resistant tall purple non-snows, seemingly every combination of characteristics, apart from the target . So how to proceed?

I set up 5 'projects' using the F3 seed material I had harvested.

TPM - Tall Purple Mammoth, looking for a big podded purple snow, with no disease resistance
TMM - Tall Mauve Mammoth looking for a big-podded half purple snow, no disease resistance
RPC - Resistant Purple Chamber of Death - looking for a highly resistant purple snow, tall or short
RMC - Resistant Mauve Chamber of Death - looking for a highly resistant half purple snow, tall or short.
 TYS - Tall Yellow Snow - looking for a tall yellow snow, with big pods and good flavour, with no disease resistance.

I thought I could persue these lines, using selection and even if I didn't get the desired target, I could use the mauve lines to back cross or cross together if they had the desirable characteristics. Rather than plant a few of everything, I selected the most promising parents, and grew out 6 seeds from 12 of the lines in foam boxes in the shade through the middle of summer - didn't really work, with only one or two lines producing any seed. So in autumn, I resowed a lot of the F3 seed, and a couple of F4 mauves that had done OK (plant 6).

So now I have a pile of F4 seed from the autumn growouts, but most plants only produced one or two small pods. This is disappointing on a number of fronts - I didn't get to test the quality of the pods, and there isn't really enough material to do big selected F4 growouts to check on homo/heterozygosity.

Dividing the lines early into Purple and Mauve projects was a bit premature - the purple lines produced sufficient mauve material in the F3 plants to go on with, but suprisingly, some of the mauve lines produced nearly full purples. This is a suprising result since pod colour is supposed to be controlled by 3 dominant genes, but it sure looks like there are other things going on here, with the purple sometimes being expressed in the later pods on a plant, but not on the early ones, and a number of different patterns of semi purple expression.

Another problem is the sheer amount of different material that is produced. I now have thousands of seeds in four generations across dozens of lines - just cataloging and storing it all takes so much time. And then making decisions about which lines to persue in my limited garden space - whew!

On the long drive between Halls Creek and Alice Springs and points further south, I spent a couple of days working out the probability of homozygous recessive genes being expressed in say an F3 generation if the F2 parent is heterozygous. My question was "How many plants would I need to grow of say an F3 generation to tell if the F2 parent was heterozygous at one locus?"  An example might help. Say I've got a tall pea, that had tall and dwarf characteristics in its parentage. It might be homozygous tall, that is carrying TT, so it will never give dwarf offspring. But what if it is heterozygous Tt? If I grow one plant, there is a 1/4 chance of it being homozygous dwarf, or tt. If I grow two plants the chances of at least one dwarf plant showing up, and therefore indicating the parent was heterozygous, is 1/4 + 3/16 = .4375. Three plants gives 37/64, or .578. I had forgotten my binomial distributions, so basically went back to first principles to figure it out.  I seem to recall that I came up with 6 plants to be around 82% sure, which doesn't meet the requirements of an ecology experiment, say, but will do me in my garden.

So how does this help me? If I want to find a purple snow, I can grow out 6 from a purple non-snow parent to see if one of the low fibre recessive genes is lurking there. This will let me know with about 80% confidence, whether the line is worth continuing on with or not. If it has no snow pea genes in it, then I can save time and space by rejecting those lines that are unlikely to produce what I want.

So I'm going with a combination of selection and mass grow out - growing 6 or so plants from all the purple lines, all of the seeds in the lines where purple is apparent but snow is also present, and a few 'hedge my bets' lines, that might prove to be promising parents for some characteristics if the purple growouts are not too succesful and I need to cross back to something for desirable characteristics. Pity that such a cross would need another couple of generations to roduce results, but hey, that's plant breeding!
No pics at the moment, but more to follow

18 August 2013

A late winter update - F1 carrots

A quick update after 3 months away from the garden. Around April I broadcast sowed a 2.5 metre bed with the seed from my seed seive tray that didn't get collected, the stuff that fell through the mesh.

The bed got thinned just before I left for my extended holiday in May, and had a few subsequent thins from the house sitter.
Most of the carrots (that may or may not be F1s, since they are the result of a mass interplanted mix of varieties which might have crossed, but also may have selfed. Below, a handful of the thinnings from last week, showing a majority of yellows and whites, which might be because of dominant genes, the  mix of varieties in the seed mix, germination  success, or chance.

30 July 2013

Am currently away from my garden on extended leave.
But constantly thinking of possible crosses and grow outs. Home in a couple of weeks, to commence spring plantings...

12 May 2013

Potato Onion seedlings

I was lucky enough to receive some seed of Kelly Winterton's potato onion seed. With some nurturing, I've got about 15 seedlings up. I've held back the majority of seed to sow next spring, but just had to try some over autumn.
Since I'm going on holidays, I've planted half in the garden, and entrusted half of the seedlings in a pot to the green hands of my mother, who will look after them in my absence.

I've also got one seedling from the topset onion plants that I assiduously de-bulbilled over summer, trying to induce flower set. About 10 seeds resulted, most of them rather thin and weak looking. I got one seedling to survive, and am wondering where to plant it with a chance that it will survive 3 months of neglect.

F3 pea progress

My January and March plantings of my F3 seed from my most promising lines of yellow snows mauve snows and purple snows are just setting pods - but I'm due to go on leave this week for the next 3 months touring the desert and Kimberley. I tried to time my holidays to occur after pod set, but miscalculated. Hope my quickly instructed assistant Craig will document and pod collect in my absence.
There are some very promising lines in the earliest flowerers - a wonderful wobbly podded yellow snom, and lots of purple and mauves to explore - but none seem to be snows at the moment. I've got dwarfs, and disease resistant lines going as well, so hoping for a big growout next spring. I will have 30 metres of row at my new garden, so have decided to commit the whole big bed to peas for spring.

Late pasnip flowering

My parsnip plantings were designed to
  1. cross up some promising lines, and 
  2. do a seed increase of Kral.
The first planting of 4 different varieties was autumn last year - about 14 months ago, with the plan to get some  autumn growth, have plants subjected to a winter regime, then get flowering in the summer. This worked, and I've got lots of potentially crossed up seed.
The second planting to increase Kral was in the early spring about 7 months ago, with the plan to grow them out over summer, over winter this winter just approaching, then collect seed next summer - but the Krals have panicked, and most of them have put up flower stems, with buds forming. Oh woe! I'm worried that winter won't be suitable for seed to mature. And I'm not going to be around for the next 3 months to check progress. Hope they last 'til August.

03 April 2013

Parsnip progress

A while since I posted - gardening takes time.
Finally the seeds on my Short Fat Parsnip parents are ready. The Halblange and De Gurnesey have set seed synchronously, but the Kral, and the late-planted Melbourne Whiteskin have been tardy. This has implications for parsnip breeding, since the trigger for flowering is presumably day length - manipulating these varieties so that they flower together will take a bit more thought than say for corn, where you can stagger planting times. Don't think that will work for a biennial. But I think there has been sufficient overlap in flowering to allow some cross pollination.

But this difference in flowering times has further implications. Accepted advice when seed collecting is to harvest the best seed. In the case of parsnips, it looks like the first umbels have the best seed. And recall that parsnips need a big gene pool for a healthy breeding population. So in a perfect world I would collect the seed from the first umbels of all four varieties I'm growing.  But the first umbels on the early flowerers won't have crossed with the later varieties. So I've seperately bagged the seeds from what I hope are contemporaneous seed heads - the earliest from the Kral and Melbourne Whiteskin, and the second pick from HLW and DG which started flowering earlier.

On another note, the second sowing of Kral which took place in early Spring has survived the record dry, but a number of plants have started to send up flower spikes. This presents me with a dilemma - do I havest this seed (which might develop too late in the season anyway) or do I reject this seed, since it comes from individuals that are prone to annualism rather than biennialism? I don't wish to encourage genetics that allow the parsnips to bolt in one season - I might end up with a population of bolters, giving lots of early seed, but no parsnips to eat!

Below, a picture of the DG (left) and HLW (right) parsnips I pulled after harvesting the seeds.
The HLW has tubbier tubers, so closer to my desired target.

26 February 2013

First parsnip seed

My parsips are finally seeding, the heads drying down, and yesterday I harvested the first seeds.
The 4 varieties in the first sowing haven't all flowered or seeded together, though. Halblange Weiss and de Guernsey flowering earlier than the Kral - of which I have only half a dozen plants surviving. My late sowing of Melbourne Whiteskin, which replaced a failed Kral sowing from a different seed source, is also late in setting seed.

This difference in flowering times is a bit problematic - the early seeds from the Halblange and de Guernsey will most likely have only crossed with each other, and my plan was to get a cross with the fat-rooted Kral. The seeds from the Kral are likely to have crossed with the later flowers of the other three varieties, but half a dozen plants makes for a narrow genetic base.

My plan is to harvest the late seed from the Halblange and de Guernsey, and the earliest seed from the Kral, hoping these will have crossed up, and collecting the seed from each variety separately.

It's been the driest spring/summer on record for Bendigo, and it 's been a real struggle to keep anything alive, but the breeding stock has got most of the attention, with my tomatoes now only sad dry sticks.

So just as I want some dry weather to ripen seed, it decides to rain! Gotta love nature...