Search found 423 matches

by david zlesak
Mon Feb 22, 2021 9:05 pm
Forum: Rose Hybridizers Association Forum
Topic: Flash breeding around the corner for roses?
Replies: 2
Views: 84

Re: Flash breeding around the corner for roses?

This is amazing Don!! Wow, this could be super useful in many slow to mature perennial crops. I've sat in presentations where people used transgenic apples to get early flowering and then they just select the offspring that don't have the transgene to identify possible plants that could be commercia...
by david zlesak
Mon Feb 22, 2021 8:56 pm
Forum: Rose Hybridizers Association Forum
Topic: Lifespan of frozen pollen
Replies: 3
Views: 97

Re: Lifespan of frozen pollen

Hi Duane!

I have used 2 year old pollen successfully that has been frozen. I don't know how much viability goes down for sure, but I was able to get successful seed set this past year from pollen collected 2018.
by david zlesak
Sat Feb 20, 2021 5:10 pm
Forum: Rose Hybridizers Association Forum
Topic: A lot of work and a little luck
Replies: 12
Views: 251

Re: A lot of work and a little luck

Your seedling is gorgeous!! I love the glossy dark leaves and full petaled blooms. Is it a miniature? I've gotten seedlings with some similar characteristics out of 'Rise 'N Shine'. Minis can be great for helping produce a nicely branched plant (as well as polyanthas).
by david zlesak
Thu Feb 11, 2021 10:59 am
Forum: Rose Hybridizers Association Forum
Topic: New: Nitty Gritty Series
Replies: 2
Views: 244

Re: New: Nitty Gritty Series

I'm excited to hopefully find them this summer and try them. They look really nice. It is great Monrovia has the option to buy them on their website and we can have them dropped off at a local garden center that buys in Monrovia products with their trucks going that direction anyways. It seems reall...
by david zlesak
Sun Feb 07, 2021 5:55 pm
Forum: Rose Hybridizers Association Forum
Topic: My Yellow Hybrid China, Champagne Bubbles
Replies: 9
Views: 470

Re: My Yellow Hybrid China, Champagne Bubbles

Your hybrid looks beautiful Joan! Those roots on the cuttings look really nice and robust too!!
by david zlesak
Mon Feb 01, 2021 11:20 pm
Forum: Rose Hybridizers Association Forum
Topic: Alternate source for repeat bloom
Replies: 41
Views: 4299

Re: Alternate source for repeat bloom

I wish I understood the interactions between the genes in the flowering pathway better... I get confused easily and have to review the basics again when I try to keep straight in my mind the role of RoKSN (aka TFL1), FD, Leafy, etc. Anyways, in 2017 at the rose meetings in Anger Dr. Fabrice Foucher ...
by david zlesak
Fri Jan 29, 2021 10:19 am
Forum: Rose Hybridizers Association Forum
Topic: Rust
Replies: 8
Views: 773

Re: Rust

Hi Larry,

If I remember right the ones I sent trace back to seed sent from Boerner Botanical Gardens in the Milwaukee area in the 1960's or early 1970's, but I couldn't find information on where they obtained their plants.
by david zlesak
Thu Jan 14, 2021 3:56 pm
Forum: Rose Hybridizers Association Forum
Topic: Koppen Geiger Climate
Replies: 2
Views: 250

Re: Koppen Geiger Climate

Hi Sarah! The American Rose Trials for Sustainability (trustedroses.org) uses this system too for regional awards. The combination of temperature and precipitation patterns seems to make it more useful than just the minimum coldest temperature like for the USDA Cold Hardiness zones https://www.ameri...
by david zlesak
Sat Jan 09, 2021 12:03 am
Forum: Rose Hybridizers Association Forum
Topic: Another virus that infects roses found
Replies: 2
Views: 203

Re: Another virus that infects roses found

Dimitre and Maher do such great work and it is nice they are mentoring others in these techniques. I'm grateful they continue to do virus discovery work with roses, especially when it is generally easier for them to secure money to characterize new viruses in other crops.
by david zlesak
Wed Jan 06, 2021 8:45 pm
Forum: Rose Hybridizers Association Forum
Topic: opinions on retaining a seedling
Replies: 3
Views: 297

Re: opinions on retaining a seedling

I doubt it too.... The resistance is dominant. Brite Eyes has only one copy of that dominant allele across its 4 sets of chromosomes and just a portion of its seedlings inherit it. There is a race of black spot that can overcome Brite Eyes, but most all the races in our collection don't. If your BE ...
by david zlesak
Tue Dec 29, 2020 11:37 pm
Forum: Rose Hybridizers Association Forum
Topic: Can Somebody Explain 'Replicative Fading'?
Replies: 9
Views: 558

Re: Can Somebody Explain 'Replicative Fading'?

That's a great question... I assume they mean that through many years and propagation cycles plants begin to show "drift" / decline in terms of performance, especially if careful attention isn't given to propagating from just the most representative plants. For part of my Ph.D. I studied performance...
by david zlesak
Sun Dec 27, 2020 6:06 pm
Forum: Rose Hybridizers Association Forum
Topic: Rooted Cuttings Failure Question?
Replies: 33
Views: 2364

Re: Rooted Cuttings Failure Question?

Hi Philip, I ordered the liquid form of Bti from a Florida pond supply company (123Ponds; I think it was a 6 or 8 ounce bottle, I have to check- it was about $20 I think). Their main customers are using it for mosquito control in ponds and that is what is on the label when it came, but the website s...
by david zlesak
Fri Dec 25, 2020 5:35 pm
Forum: Rose Hybridizers Association Forum
Topic: rugosa x glauca
Replies: 6
Views: 758

Re: rugosa x glauca

Hi Duane!! I'm excited for you to follow these. Hopefully you can just put them all into larger pots and prune them as needed to keep them all in their space allotted until spring. It would be a shame if they vary for health and other traits and you miss the opportunity to discover those things at t...
by david zlesak
Tue Dec 22, 2020 11:42 am
Forum: Rose Hybridizers Association Forum
Topic: Rooted Cuttings Failure Question?
Replies: 33
Views: 2364

Re: Rooted Cuttings Failure Question?

That is wonderful rikuhelin1!! I'm so glad they are taking. Thank you so much again Stefan!! I got Bacillus thuringiensis subsp./var. israelensis and it is working. After the first application it really knocked the fungus gnats down and a couple weeks after now I mixed some more and treated again. I...
by david zlesak
Thu Dec 17, 2020 3:06 pm
Forum: Rose Hybridizers Association Forum
Topic: Scandinavian Import ID Challenge - Needle in Haystack Quest?
Replies: 25
Views: 3176

Re: Scandinavian Import ID Challenge - Needle in Haystack Quest?

Hmmmm It looks like the rose I've seen in the past at the MN Landscape Arboretum labeled 'Kakwa', a spin hybrid. The wide hypanthium under the sepals suggests Spin hybrid to me. At the MNLA 'Kakwa' got about chest high and 6-8' wide and died back somewhat each winter.
by david zlesak
Sun Dec 06, 2020 11:41 pm
Forum: Rose Hybridizers Association Forum
Topic: Rust
Replies: 8
Views: 773

Re: Rust

I added a link to a paper by Dr. Kermani et al., 2009 characterizing various species of fungi causing rust in roses. This seems like a pretty diverse group of pathogens for having such a variation of species causing similar symptoms and growers calling it all by the same disease name. http://www.glo...
by david zlesak
Sat Dec 05, 2020 11:29 pm
Forum: Rose Hybridizers Association Forum
Topic: Rooted Cuttings Failure Question?
Replies: 33
Views: 2364

Re: Rooted Cuttings Failure Question?

Wow, thank you sooo much Stefan for pointing out Bacillus thuringiensis and this strain labeled for fungus gnats. I'm super excited to get some and think it'll be less expensive and have a longer residual than hydrogen peroxide. It becomes difficult for me with lots of seedling trays of small cells ...
by david zlesak
Fri Dec 04, 2020 7:32 pm
Forum: Rose Hybridizers Association Forum
Topic: Rooted Cuttings Failure Question?
Replies: 33
Views: 2364

Re: Rooted Cuttings Failure Question?

One thing I've tried last year that has really helped with fungus gnats with seedlings is hydrogen peroxide. I've mixed it about 1 part 3% from pharmacy to a few parts water. The media bubbles and kills the larvae and hasn't seemed to impact roots of rose seedlings. It takes a few applications since...
by david zlesak
Fri Dec 04, 2020 3:58 pm
Forum: Rose Hybridizers Association Forum
Topic: Rooted Cuttings Failure Question?
Replies: 33
Views: 2364

Re: Rooted Cuttings Failure Question?

I notice that too.... I wonder too if I have them too wet. I suspect in some instances the blackening may be due to one of the root rot organisms getting in and disrupting the vascular system and connection between the top of the cutting and roots. Sometimes when I have cuttings I'm potting up and t...
by david zlesak
Wed Dec 02, 2020 11:50 am
Forum: Rose Hybridizers Association Forum
Topic: i.d. this rugosa hybrid???
Replies: 12
Views: 797

Re: i.d. this rugosa hybrid???

This is just a guess, but 'David Thompson' from Svejda. It was popular "a long time ago" in relative terms (~20 years ago) and routinely sold for awhile with her other wonderful Explorer roses. I think it is more petite in terms of its leaf size than the other commonly sold double magenta rugosas.