Citrus Growers Forum

Roberto · Posted: Mon 03 May, 2010 2:11 pm

Question to the experts,

what is special with Pt "Rubidoux"?

/Robert

Millet · Posted: Mon 03 May, 2010 5:35 pm

Nothing special, unless you happen to live in Riverside, California where a mountain, a hotel, a city park, a high school, a drive in theatre, and a church are all named Rubidoux. - Millet (987-)

Roberto · Posted: Mon 03 May, 2010 6:36 pm

But it is said to be destinguishable from other Pinciruses. what is special?
/Robert

Las Palmas Norte · Posted: Tue 04 May, 2010 5:34 am

Apparently in name only.

Cheers, Barrie.

ivica · Posted: Wed 26 Jan, 2011 4:50 pm

Just did some googling in the search for answer to my own such question, and have found this topic.

Source of my confusion was
"At the present the only Citrus trifoliata clone whose behaviour is sufficiently well established to warrant naming is Rubidoux..."
from "Citrus Pages" at http://users.kymp.net/citruspages/trifoliates.html
and hence the question "Why?"

Text cited above can be found also here
http://www.citrusvariety.ucr.edu/citrus/rubidoux_trifoliate.html
pointing to the source: "The Citrus Industry Vol. 1 (1967)"
http://lib.ucr.edu/agnic/webber/Vol1/Chapter4.html#trifoliate

Consequence could be that "Rubidoux" is more often then others used in scientific experiments, quite recent one as example:
Boava et al., 2011., "Global gene expression of Poncirus trifoliata, Citrus sunki and their hybrids under infection of Phytophthora parasitica"
http://www.biomedcentral.com/1471-2164/12/39

Older one with interesting use of "Rubidoux":
Moreira et al., 2002., "Inheritance of Organelle DNA Sequences in a CitrusPoncirus Intergeneric Cross"
http://jhered.oxfordjournals.org/content/93/3/174.full
... DNA of the cultivar Rubidoux was used to identify P. trifoliata-unique organelle DNA configurations. We do not know if the paternal tree was identical to Rubidoux in all mtDNA configurations, but the maternal tree was available for analysis..."

My conclusion, combining Millets answer and my observation, is:
There is nothing special about "Rubidoux" wrt other PT varietes,
"Rubidoux" is simply taken, by scientific community, to be representative one for PT as a whole.

_________________

bussone · Posted: Wed 08 Jan, 2014 9:09 pm

Roberto wrote:

But it is said to be destinguishable from other Pinciruses. what is special?
/Robert

http://www.citruscongress2012.org/web/wp-content/uploads/downloads/2012/11/LIBRO-CONGRESO-CITRUS.pdf

S08P11 -- it's demonstrably drought-tolerant.

Quote:

S08P11
Characterization of water deficit tolerance of Poncirus trifoliata genotypes as related diversity
Ben Yahmed J.1, Costantino G.2, Ben Mimoun M.3, Talon M.4, Ollitrault P.1, Morillon R.1 and Luro F.2
1Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), Amélioration des Plantes à
Multiplication Végétative, France; 2Institut National des Recherches Agronomiques (INRA), France; 3Institut National Agronomique
de Tunisie (INAT), Arboriculture Fruitiere, Tunisie; and 4Centro de Genómica, Instituto Valenciano de Investigaciones Agrarias (IVIA),
Spain. jihene.benyahmed@gmail.com
Rootstock provides better adaptation to biotic and abiotic constraints. Poncirus and its hybrids are widely
used since they are tolerant to Citrus Tristeza Virus. However, when grafted, most of them are considered
to be sensitive to salinity and water deficit. Diversity does exist within the Poncirus trifoliata specie but
little is known regarding the behaviour variability of genotypes to abiotic constraints. The citrus diversity
of 72 P. trifoliata genotypes was investigated using SSR markers. Two mayor genetic groups were clearly
identified. Five genotypes, belonging to each genetic group, were then selected to investigate their properties
of tolerance to water deficit. Water deficit was applied by withdrawing irrigation for 4 weeks. Physiological
parameters such leaf stomatal conductance and quantum yield of PSII electron transport, soil water potential,
leaf osmotic pressure and transpiration were estimated. Among genotypes, we observed that some genotypes
such as Rubidoux were clearly more tolerant to water deficit than others such as Pomeroy. Interestingly,
the genotypes that were sensitive belonged to one genetic group and the tolerant ones belonged to the other
group. Therefore, it sounds that among the Poncirus genus, it is possible to select genotypes as parent in
breeding programs, which are more tolerant to water deficit.

Some work out of China suggests that PT is certainly broadly capable of drought- and salinity-resistance, but doesn't always exhibit it.

yuzuquat · Posted: Thu 09 Jan, 2014 5:01 am

Rubidoux is just the currently used cultivar of poncirus, no special features - large flowered, moderate vigour. It is however possibily more nucellar and seedy than other highly nucellar and seedy plant.

So growers get more seedlings and more consistancy from each fruit.

Millet · Posted: Thu 09 Jan, 2014 12:58 pm

.........but less tree dwarfing. - Millet

elsedgwick · Posted: Thu 09 Jan, 2014 1:06 pm

A guy I know stated that the benching that can be an issue with Trifoliata and Tri-hybrids is less pronounced in Rubidoux, but the only data I've seen (http://plantbiology.ucr.edu/faculty/Baker-Moro-06-Summ1.pdf) suggests that Rich 16-6 is marginally better at not benching, and that the very common Swingle is worse, at least in combination with Moro oranges.