Low take rate on 1st flush, high take rate on the second

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mnemko
Posts: 64
Joined: Wed Feb 21, 2018 7:36 pm

Low take rate on 1st flush, high take rate on the second

Post: # 73045Post mnemko
Sun May 30, 2021 3:14 pm

This is the 2nd year I've been using Oso Easy Italian Ice as a female. Last year, I had one plant of it, and had only a 5% take rate on the first flush of blooms and 80% on the second. This year, I have three plants of it. All are finishing their first flush. The plant I had last year, again seems to have a very low take rate, but the other two seem to be taking quite well. Of course, all are cultured similarly: size of pot, soil, fertilizer, sun, water. And the weather is not appreciably different between the first and second flushes: no rain, dayitme highs of 65 to 80. Do you have a hypothesis as to what is causing this?
Marty Nemko
mnemko@comcast.net
510-655-2777

david zlesak
Posts: 461
Joined: Tue Nov 26, 2013 12:27 pm

Re: Low take rate on 1st flush, high take rate on the second

Post: # 73058Post david zlesak
Thu Jun 03, 2021 11:28 am

That's a great question Marty. I don't know the answer, but maybe there could be some fertility / environmental interaction due to Italian Ice being triploid (I just double checked my ongoing file of roses I've counted the chromosomes of and see I counted it). Perhaps under different temperatures/variations in physiology from the first to the second flush, etc. the efficiency of meiosis and segregation patterns of chromosomes may be slightly different leading to a higher rate of balanced gametes in the second flush? It is sure a beautiful rose.

mnemko
Posts: 64
Joined: Wed Feb 21, 2018 7:36 pm

Re: Low take rate on 1st flush, high take rate on the second

Post: # 73061Post mnemko
Fri Jun 04, 2021 3:10 am

That makes sense. There has to be some climactic and solar variation---obviously the sun is more direct in June than in May. Yeah, Italian Ice is not just beautiful but very floriferous, absolutely no disease here in Oakland, CA although David Byrne reports it gets cercospora in TX.

And forgive my ignorance, does it being triploid mean that if I cross its seedlings back with it or another seedling with it as parent, it will be sterile?
Marty Nemko
mnemko@comcast.net
510-655-2777

david zlesak
Posts: 461
Joined: Tue Nov 26, 2013 12:27 pm

Re: Low take rate on 1st flush, high take rate on the second

Post: # 73066Post david zlesak
Fri Jun 04, 2021 11:59 am

That's a great question. I suspect you'll find a wide range of fertility and ploidy levels among your seedlings and some cross combinations, etc. will be easier than others. It would be fun to get some offspring of it with higher fertility that could make carrying the good genes forward easier. I get a little cercospora on it here (most everything gets a little bit), but it isn't too bad, so at least here it has some moderate tolerance to it thankfully.

mnemko
Posts: 64
Joined: Wed Feb 21, 2018 7:36 pm

Re: Low take rate on 1st flush, high take rate on the second

Post: # 73069Post mnemko
Sun Jun 06, 2021 4:02 pm

I'm aiming for compact minis of health with HT form: So, if that appeals, you might try Rainbow's End and/or Happy Trails. I'm also using a couple of my healthy seedlings. If you'd like some pollen, email me your mailing address. My email address is mnemko@comcast.net. (That's because I don't often check the RHA site.) If I were aiming for somewhat larger, I might try Sexy Rexy.
Marty Nemko
mnemko@comcast.net
510-655-2777

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