Crossing advice needed

[crmauch]

This was the first summer that I attempted to cross-pollinate tomato flowers. I have successfully previously crossed Christmas cacti and garden peas. I am frustrated in that of all the crosses I attempted (I don't have an exact count, but I'd say in the neighborhood of 12-20), I only had two takes. Ironically they were both with a cherry tomato (Super Sweet 100) as the maternal parent (and the 2nd cross, on July 28th was lost to late blight).

I had 4 tomato varieties (Roma, Husky Gold, Golden Jubilee, Super Sweet 100). None of these are central to what I hope to breed with tomatoes, so I considered it a 'practice' year. Next year, if things go the way I hope, I plan to start a breeding program with actual goals in mind.

I attempted to gather pollen two ways:

1) I tried the 'toothbrush' method, with a piece of cardboard covered with black electrical tape. I was only occasionally successful gathering pollen this way.

2) Later in the season, I gathered flowers at the just about to open, dried them for a day and attempted to scrape the pollen from inside of the anther cone (the only problem is this is knowing whether your getting pollen or just stamen bits) and then placed it on the electrical taped cardboard.

I attempted to transfer the pollen in two ways:

1)I either touched the pistil to the cardboard, or

2)I used a animal hair brush (the problem with touching the cardboard to the pistil is that I sometimes broke off the pistil even though I thought I was being gentle.

I rarely attempted a 2nd pollination. When I did, often either the tip of the pistil seemed dry, or it broke off.

I believe I emasculated correctly and at the correct stage.

I did not cover any blossoms before or after pollination.

I did not remove any other flowers from the inflourence.

I'd realy like to use the remaining 'plant' for tomoto production, I realy don't want to have a plant for 'crossing' only.

About 1/2 my crosses were in the morning on Saturday or Sunday, I also attempted many crosses in the evening after work.

What is your percent 'take' (estimates and guesses are fine). Any thoughts of what I am doing wrong?

Thanks,

Chris

[joseph]

I recommend choosing a different pollen donor. Chose a plant as the pollen donor that releases clouds of pollen when vibrated. That'll greatly simplify your life. Those plants can be identified in my garden because most any time I visit the garden there will be a bumblebee spending lots of time on the plants that release lots of pollen. Only about 5% of varieties release copious pollen. Jagodka and Nevskiy Red were two varieties in my garden this summer that released lots of pollen.

A few years ago I ate all my potato varieties that failed to release copious amounts of pollen. It's the best thing I ever did for my potatoes. I'm working up the nerve to do the same thing this fall with my tomatoes.

[tlintx]

I never saw much pollen when I was trying this year either. For me, it was the humidity, I think. Heat also contributed. The most humid part of our day is the morning, the hottest the afternoon.

[crmauch]

Originally Posted by joseph

I recommend choosing a different pollen donor. Chose a plant as the pollen donor that releases clouds of pollen when vibrated. That'll greatly simplify your life.

I don't know that I ever saw a bumblebee on my tomato flowers (they much preferred the cantaloupe flowers nearby), but I did see some of what may have been sweat bees. The funny thing is I did have a few flowers produce copious pollen via vibration, but other flowers on that same plant at different times did not produce much in the way of pollenm. Also when I got pollen, pollination did not take.

[travis]

There are optimum moments on optimum days when blossoms ready to blow actually will respond with a big pollen blow when vibrated. These moments come and go quickly, and are influenced by temperatures leading up to the moment, relative humidity, barometric pressure, wind velocity, and other environmental conditions.

You are lucky if you catch a blossom at an optimum moment.

Also, since you indicate sweat bee activity, many of the blossoms from which you attempted to harvest pollen may already have had their pollen harvested by those bees who inherently detect the optimum moments of pollen release.

Look for visibly swollen anther cones - cones that look pregnant in comparison to other anther cones on the same plant.

Use a sunglasses lens or a black plastic spoon rather than your black tape covered cardboard slide.

If you collect a small pool of pollen in one spot on the lens or spoon so that the pool is several layers of pollen grains deep, you will be able to gently nudge the stigma onto the top layer of pollen grains without jamming the pistil into a bow.

Be very gentle!

Also, grow some larger, rougher varieties like beefsteaks that have fascinated stamen structures and use them for the female pollen receptors. Use the cherries and more refined shaped varieties with more delicate pistils as the pollen donors.

And finally, believe me, you are not the only one who attempted dozens of manual crosses and only had a couple takes.

[bower]

Yep, I take a little comfort that the web guidance says "expect failure". I decided to chance a few crosses late in the season rather than do none, but I had a lot of difficulty getting pollen from the intended donors. Like you I tried the many methods but certain plants just weren't giving out any, for whatever reason. Overall the best technique for me was to hold a lens or plastic receptacle under the flower and tap the stem repeatedly with my finger so the anther cone also tapped against the lens and shed pollen there.

I did find a couple of varieties that produced copious pollen, so I did some crosses with them just to practice the technique. I was pretty amazed that certain pollen donors would produce a 'take' every time, or with just one application, while I fussed and repeated the others to no avail. Overall I didn't get better than 50% success though. And some of the ones I really wanted, did multiple and reciprocal crosses, failed across the board this time.

I understand that pollen keeps fairly well in a cool place, so thinking in future to collect pollen first, then get the female ready, especially if (like now) there aren't oodles of blossoms available.

I did do multiple applications of pollen for several days. I noticed that on the first day, the pistil typically appears to be a straight tube, but after a day or two a little knob can be seen on top. I'm thinking that is the sign it is mature and ready, and the little knob sops up pollen pretty nicely. You know it's sticking when the stroke leaves a line thru the pollen on the lens.

[KarenO]

I tried for the first time this year and after many different tries two finally worked. I use the electric toothbrush and sunglasses lens and learned over time that time of day seemed very important for collecting pollen with about 11 to 4 pm being the best on dry sunny days. Anyway I am a beginner and was pleased to get two. Pollen donor for both was captain lucky and the two female parents were delicious and Ludmilla's pink heart. Will be fun to see what comes of it next year and beyond. Purely for fun it is my dream to make my own tomato
Keep trying. I was told that smaller tomatoes are easier and I tried lots but funny these were the two that took. I think it was the pollen with CL giving lots. All of these three taste very good so hopefully those taste genes will be passed down.
I had to pick them not yet ripe as it will freeze here tonight. The pros here would chuckle if they could see my two precious tomatoes with DO NOT EAT!! written in sharpie marker nestled like treasure to ripen in my china cabinet where they can come to no harm. lol keeps any unwary family member from getting in my bad books forever for making a sandwich out of my precious offspring!
KarenO

[crmauch]

Deleted

[crmauch]

Thanks everyone for their thoughts. I'm glad I'm not the only one who had difficulty. I'll try to get a hold of a lens. The 11-4 timeframe is somewhat problematic as that usually when I'm at work. And weekends don't always work out as either other commitments or weather interfering.

If anyone else has more thoughts, I'd be glad to still hear them.

CHris

[KarenO]

Dollar store sunglasses will work. If you are trying to collect pollen in the evening or early morning that may well be the trouble.
Karen o

[ChrisK]

A black disposable plastic spoon works too, as does a piece of thick paper or card stock blackened with a sharpie. I often pollinate after work when it cools down. An electric toothbrush works well to get recalcitrant pollen out of the cone!

Keep practicing. Soon it will be rare that a cross doesn't take!

[bower]

Pieces of hard shell plastic packaging worked well for collecting and applying pollen. I had some pkging from SD cards which was great, little square dimples, but pieces of the flat plastic worked well too, and easy to label it with a sharpie.

I don't remove other flowers from the inflorescence either, unless they are above the cross and likely to shed pollen on it. I take off the sepals from the crossed flowers and mark the whole cluster with a loose tie and tag, so there's no weight or constriction around the flower itself.

I agree that early morning and late evening are the worst for getting pollen. But I have gotten a cross to take with pollen that was collected 5 days before, and kept in the cool basement. You might try collecting your pollen on the weekend, store it cool and apply it after work.