A Critical Review of the Female Gametophyte in the Podostemaceae - Past, Pres...
Begonia albo-picta Explained
1. CodyGramlin
April 17, 2016
Begonia albo-picta Explained
Introduction
Begonia albo-picta isa small shrub-like plantknowntobe grownaroundareasinCalifornia,USA
and NewYork,USA. It belongstothe Begoniaceae familyandissistertothree othergeneraof
Begoniaceae:Haplophragma,Symbegonia,andHillenbrandia.There are around1,500 speciesof
begoniaaswell asanywhere from1,500 to 10,000 more hybridspecies (Anderson,2007). Economically,
begoniasare significantinornamental industriesandmarketsof plantsaroundthe world.
Plant Morphology
Begoniasare knowntohave eithersimple orcompoundleaves,dependingonwhichspeciesin
particularisbeingregarded (Elite pets,n.d.).Begonia albo-picta specificallyissimple-leafed.Ithasan
alternate (distichous)leaf arrangement,andisstipulateandpetiolate.The petioleshave ablendof red
and greencolorsonthem,as well asthe newlybuddingleavesbefore full maturity (Tebbitt,2005). Male
begoniashave fourtepals,while the femalescontainfive.Aswell,malesalsocontainaroundtwenty
stamensforreproduction whilefemales containthreestyles.The specificfruitingbodyof the begoniais
a loculicidialcapsule.
Begonia albo-picta isconsideredadicot,meaningthe embryoof the plantcontainsnotone,but
twocotyledon.Aswell,the vascularbundlesof xylemandphloemare concentratedinaringnearthe
outeredge of the plant’sstemratherthan inunorganizedbundlesthroughoutthe stem (Figure 1).
Additional waysof identifyingitasa dicot include the nettledpatternof the veinsinthe leaves (Figure
2) and quantitiesof fourandfive tepals(dependingongender) ratherthana multipleof three,asseen
inmonocotplants.
Figure 1 –Vascular bundles seen ina ring around the stem Figure 2 –Cross-sectionofa leaf, showing a vascularbundle
2. AuxinDominance
There isa technique thatcanbe performedonbegonias,andanyother plantforthat matter,
knownas “pinching-back,”aswell asmanysimilarnames.Essentially,one pinchesthe apical meristem
(the endingparton the shoot where primary growthoccurs) withtheirfingersorperhapsasmall tool,
and removesit.Withoutthe apical meristem, the plantcannotgrow verticallyandinsteadbeginsto
grow laterally fromthe axillarybudsalongthe lowerpartsof the stem.
The active apical bud suppressesgrowthof lateral shootsuntilithasgrownfar enoughfromthe
meristemonthe axillarybud.Here,the concentrationsof the hormone,Auxin,are muchlower.Axillary
meristemsremaindormantuntilthisconcentrationdecreases.Pinching-backonthe apical meristem
altersthe concentrationsof auxintodisplace,allowinglatergrowthtoproceed(P.Goldsborough,
personal communication,February26,2016).
GeneticCharacteristics
Begonia albo-picta hasa chromosome numberof 2n=56 (Tebbitt,2005). Albo-picta isknownas
the,“firstspeciesinwhichF1-hybridscultivarswere developed.”Itwasa resultingspeciesfromthe
Begonia semperflorens andBegonia schmidtiana (Anderson,2007). Regrettably,thisleaves albo-picta
relatively,if not,completelysterile.Thisspecies,aswell asmanyotherspeciesof begoniaare excellent
examplesof geneticallymodifiedorganisms(GMO’s).The primarytraitswhichare commonlyalteredin
the processof modificationwouldbe thingslike the sizeof the plant,variouscolorsforthe petalsof the
flowers,andenvironmental anddiseaseresistancesforlongevity.
Disease
One noteworthybacterial diseaseBegonia albo-picta isknowntosuccumbto wouldbe Bacterial
Leaf Spot andBlight.It isrecognizable byayellow circularshape thatwill developonthe leaveswhich,
one by one,slowlydie.Thisdiseasecomesfromthe bacterium Xanthomonascampestrispv.begoniae.
As well, afungal diseaseworthmentioningwouldPowderyMildew fromthe Odium fungus.Itis
recognizable byawhite fungusthatgrowson the leaves,flowers,andstemsof the begonia.The areasof
planttissue affectedby Odiumare likelytodie (PennState,2016).
Conclusion
At the beginningof the semester,all studentsinBTNY11000 were givenasmall Begonia albo-
picta plantto raise ontheirownfor the opportunityof upto two extrapercentage pointsof credit.The
plantI initiallychose toraise wasrelativelysmall,thoughthe largerof the groupof plantsfromwhichto
choose. Forfun,I decidedtoname the begonia “Frank”aftermy labteachingassistant,whoisexcellent
at hisjob andtakestime to make sure the studentsunderstandtheirworkratherthanjustgivingout
answersforfree.
The begoniahadfour leaveswhenIfirsttookitto mydorm and wasa heightof around9
centimeters(Figure 3).Withinthe firstfew weeks,andhavingneverownedaplant,IdiscoveredthatI
was slightly overwateringit.Ireducedmywateringfrequencyfrombetweenone toone anda half
weeks.Aroundthe time SpringBreakbegan,there wasstillnoprogressingrowth(Iassume because of
the cold wintermonths).Itwasalsoaroundthistime thatI had purchaseda small amountof off-brand
3. fertilizerhighinnitrogenandphosphorous.Ihadalsobegunputting the begoniainthe window,rather
than a desklight,since itwasno longercold.
Growth jumpedbylarge amountsastime progressed.Comingtothe conclusionof the
semester,“Frank”nowhasa total of elevenleaves,withanadditional twoleavesinthe processof
budding.The stemnowreachesa height of aroundelevencentimeters andisnow at a slightleanfrom
the weightof itsnewgrowth (Figure 4). I personallyfoundthisprojectveryinteresting,anda
resoundingsuccess.Iplantokeep“Frank”for manymonthsand yearsto come and hope to see more
and more growthas time progresses.
Figure 3 –Four leaves, 9cm tall Figure 4 –Eleven leaves,11 cmtall, 2 buds
References
Anderson,N.O.,Hvoslef-Eide,A.K.,Munster,C.(2007). FlowerBreedingandGenetics.Begonia History
and Breeding.241-275. April 17, 2016.
Dave’sGarden.(2016). BambuisformeBegonia,Cane StemmedBegonia.Dave’sGarden. April 17,2016.
Retrievedfrom: http://davesgarden.com/guides/pf/go/58612/
Elite Pets.(n.d.).HardyBegonia,TuberousBegonia,Beefsteak(Begonia). ElitePets. April 17, 2016.
Retrievedfrom: http://elite-pets.narod.ru/room_bra27.htm
Harada, H., Kamada,H., Kikuchi,Y.,Kiyokawa,S.(2001).TransgenicBegonia. Biotechnology in
Agricultureand Forestry, Vol.48. 44-54. April 17, 2016.
PennState College of Agricultural Sciences.(2016).PlantDiseases. Penn StateExtension. April17,2016.
Retrievedfrom: http://extension.psu.edu/pests/plant-diseases/all-fact-sheets/begonia-diseases
Tebbitt,M. (2005). Begonias.TimberPress.77-79. April 17, 2016.