Posts Tagged ‘plant breeding’
In 2014, I bought a packet of zucchini seeds in early august and planted a few to fill a hole in my vegetable garden. One of the resulting plants produced very light-skinned fruits that I referred to as “blond zucchini.”
On a zucchini plant that unexpectedly produced blond fruits, I accidentally created a hybrid cross with a dark green zucchini. I collected and grew seeds some of which gave rise to blond zucchini plants. I collected seeds from the blond zucchinis of that 1st generation and plants are growing now on my plot at the community garden. This blond fruit is the 2nd generation descended from the original hybrid… but it’s not the only color of fruit to come from those blond zucchini seeds.
Whenever possible, I hand-pollinate my squash plants, and this was no exception. Unfortunately, when I pollinated my first blond zucchini, I used a male flower from a plant that produced dark green fruits. Before being pollinated, the blond zucchini looked like all the other zucchinis I’d every seen.
So, at the end of 2014, I had collected seeds from a blond zucchini that had been cross-pollinated with a traditionally dark green zucchini plant.
2015 Zucchini Experiment
In 2015 I started 4 seeds I’d saved from that first blond zucchini of 2015. Low and behold, one of the plants produced more blond zucchinis! Sadly, however, the other plants produced dark green fruits. I saved seeds from the 2015 blond zucchini, hoping they might grow into plants that produce blond zucchini.
Of four seeds I planted from my 1st generation blond zucchini, two plants are producing familiar dark green fruits. It’s likely that blond is not the dominant color.
I planted seeds from the 215 blond zucchini in April of 2016… four seeds in all.
Did I get only blond zucchinis? NO! Two plants produce dark green fruits—the classic zucchini we all know and love (loathe?) One plant produced blond zucchinis. The fourth plant produced a new shade of fruit: a yellow-green squash that wouldn’t even pass for a cross between the blond and dark green varieties.
So… given many more years to mess around with descendants from my original zucchini hybrid, I’m not confident I’d ever arrive at a stable “blond” fruit… but I’d keep trying. Of course, now that there’s a yellow-green descendant, I’d also try to develop a stable version of that.
Here’s how it looks so far:
Original hybrid cross between dark green and blond fruits resulted in plants that produce dark green zucchinis or plants that produce blond fruits.
One seed from the 1st generation blond zucchini grew into a blond zucchini plant. Two seeds grew into dark green zucchini plants. The fourth seed grew into a yellow-green zucchini plant. Clearly, there’s more than one gene involved in determining the color of fruit a zucchini plant produces. It would be very satisfying to develop a line of blond zucchinis that breed only blond zucchini plants, and another line of plants that breeds only yellow-green plants. I’ll keep messing with them and see where it gets me.
1st generation from hybrid blond zucchini resulted in plants that produced dark green fruits or plants that produce blond zucchinis.
2nd generation: seeds gathered from 1st generation blond fruits resulted in plants that produce dark green fruits, plants that produce blond fruits, and plants that produce yellow-green fruits.
Perhaps I’ll do some research on zucchini breeding. My first very casual research suggested that neither dark green nor blond is a dominant genetic characteristic and that these colors may result from a mixture of several genes (rather than a single gene controlling the color). If that’s the case, the best I might hope is to produce a Zucchini Carnival Mix where the seeds from any of my hybrid’s descendants could produce dark green, blond, yellow, or even some other color I haven’t yet observed.
I’ll keep playing and see where it gets me. In a few days, I’ll harvest one very mature blond zucchini and one very mature yellow-green fruit. I’ll collect seeds from them and immediately start them in the garden. Before first frost I’ll have a third generation of fruits descended from my original hybrid… and, perhaps, even more colors to report.
It seems likely I could package seeds that produce a “harvest mix” or “carnival mix” or some-such—any of the fruits in this photo could produce seeds that grow into all three colors of zucchini. Heck, there might be a few other shades of zuke in those seeds; perhaps I’ll coax them out of the next generation.