Prelim主nary report on the nucleus divisiorland
Chrornosomenumbersin the Oゐa euクマ妙ea L．
ti、
Kimi匝O NoRO
（Lめ0Ⅰ・a抽y of■Subtro匝al‡‡orticultur・声）
（Reeeived OctobeI・30，1952）
INTR（〉甘）UCTIOⅣ
Mission at Takahashiorchard near our college blooms？Very year but does not bear
fruit，althoughpollinizer・S are planted・The reaSOn Ofit寧being fr・uitlessis unknownup
to date．The condition of the or・Chardis not bad and any obstacleis not found there
As the writer thought that the reason ofits being fruit1ess was the pollen abortion，
the micr・OteChnicalstudies were carried out about the matter and chromosome numberin
the Olea euro少eaI，．havel〕eeninvestigatedin P．M・C．At the same time，Writer pollini・
zed Mission with the pollen of Man21anillo and Nevadillo Blanco acquiredin theg■rOund of
our college and olive orchardat Shodoshima，and Manzanilloin the grOund of ourcollege
waspollinizedwiththe pollen of Mis＄ionof Takahashiorchardolbtainrngg00dr9SultS，but
th＄reSults ofpollination at Takahashiorchard werein V？li中小By suc王1a r’eaSOn the writer
assumed thatthe pollen of Misson at Takahashiorchard was ver■y g■00d andⅥaS nOt abor・
tivや
Hart：mann（2〉reportedthat suchpheno叩enOhhadbeen甲enin CaliforTlia and they‘Werや
due tothedrynessofth？SOil・IButtheymaynottakeplaceowingtO′thatreaS9ninJapa：n・
Thisstudyisaby・・prOduct obtained壇甲the above experimentarldLVery Va1uable one
There are no recordin the world co・nCerningthenucleusdivisionof olive，butSax（5）count
ed the number of chromosomes of the Olea euY・OPea by the roottip andonly assumedthat
n equa123．
M：AT‡璽R‡A‡．S AN菖）R質記丁重ま￠貫）S
The olivs tree used were about20years old Mission，about15 yearS Old Manzanilユoin
the grOund of our college and aboutlO years old MissioninTakahashior・Chard・′ilhemate一
rials were coilected everyday from tlle2nd of MELy］952tillthedaybeforIe flower・ingand
aS the killingfluid，Carnoys（fluid was used・Thelate diakinesis and meiosis count are
based on aceto−Carmine smear preparation．rillle POllen grain were stained withl〕alafieldPs
HaematoxylinりThe materials usedinthe stetChweretakenfrom the Missionin the gTOund
￠f ou∫■COllege
1て！．the s蝕ear method based on preparatioln Of the root tip，tbe root tip of one year old
SeedlingwaS uSed and materials preceded by treatment for about half one hour with the
Chlor・alhydrate Were WaShedin the runnlngwater・and after fixedin CamoysF fruid for
about one hour，fixed againin NavashinFs 壬1uid for6・7hours at】50C．
R瓦St＿汀．TS
AllstageS Of the nucleus division，fr．om the restingStage tO diakinesis，are almost quite
normal・1’he writer・found23pairs of chromosome atthelate diakinesis and metaphase as
Sax（5）supposedn＝23fromthe roottip”（PI，．Ⅰ．Fig＼・6．7h）181
Some｝ChIlOm6somes seem・tO be consplCuOuSlylarger than others・Allchromosomes aregenerally notobservedin the same equitorialplate and the almost halfof them are obser−
Vableinli七t1e below the plate，At met牢phase polar view was easily not seenlAs shownin PIJ… t・Fig・・7，the writ、er
could count the number・S Of chro：nOSOme＄，aS Onei且thelate diakinesis，
Ⅰn side view，the halves resulting from the divisionin metaphase separateinto two
setsin such a way that half of each orlglnalchromosome madeit way towards one pole，
and the other ha．1f toward the other巾
The two se七S Of chromOSOme SO formed travelback alongthe spindle fibres，eaCh gOmg toone of the two poles of thenucleusregularly・（PIJ・TFig・9）but ontheir waytothepole
certain chr・OmOSOme Very rarely showlag・ging■l（■pIJ小Ⅰ・Fig■・10）In homotype metaphase n＝
23were also counted clearly．
Although the abnormalitiesdivisionin meiosis were rarely seen，tetrad formation w紳 a1most noて∫maland monoad，triads and polyads wer・e｝nOt foI血ed・（FしIL Fig巾3）
The form公tion from microspore to pollen grain was almostnOrmaland each s均ge waS
Seen aSin Pl．T工．Fig．5．6．8butthe writer regretted that although preparates were stained with DelafieldTs f王aematOXylin，nuCleus divisionin pollen gTain was not，Observed・
Simultaneously with the g・ermination of pollenin August，the writer observed only one time the metaphase stag・ein side view，but didnotnoticeitat that timel・The confirmation Of the nucleus divisio：ユin the pollen gTainisleft for the future study・
Thepollen grain，perfectandimperfect wereobserved．The proportionof them betWeen
Mission and Nevadillo Blancois seenin tableland also the size of themin table2u Tablel．
Proportion of the perfect andimperfect pollen grain
Mission Nevadillo］∋1anco
Date No．used Perfect1mperfect No．used Per・fect
pollen pollen po11en
1mper絶cf
pbllen
Aug■． 422 92％ 8％ 1955 77．4％ 18 32．6／％ Table2 Size of perfectandimperfect po）1en grainNevadillo迅1a琴CO NO．used Diameter Diametei
Of perf． ofimpei・f． pollen pollen
n4issidn Date No．used Diameter Diameter
Of perf． ofimperf・ pollen pollen
Aug． 200
24／J
16／（18
200 26／（ 20／〈
The writer regretted that the nucleusdivisionof NevadilloBlanpocouldnotbeodserved・ Th？pointofs紘iking、COntraCtbetweenthenucleusd毎isio享IOf MissionandNevadも恥すBlancp
皿ight be see甲・
during■ about70days，the observation at the blooming time＼may have had different re−
＄ults．
The writer．observed the number of chromosomesin metaphass on the preparates of the
root tip，they could not，however，be counted accordinglotheimper・fect！On Of theinstrum・
ent．
わISC一丁SSION
Accordingr to such a fact，the r・eaSOn Of thefruitleessness are different from those whch
Prof．Asami（1）gOtfromthestudy onthepollenabortionin Shanghaipeachandnevercoin− cide with Hartmann，s study（2）．That reason of′the fruitlessnessis quiteobscure andthe
writer is going to stucly the new reseaxches.
The fact that all chromosomes are generally not observable in the same equitorial plate
ar∋above the｝Writer，s comprehension but the differenCeS Of the size of chromosomes were studiedin Rhodorendoon and‡払1sam by Nakamura（31・4）andin the Oleabeaeby Sax・（5）The w工・iter regTetted thatthe nucleus divisionin the pollen grain was not observed and
the fact which the nucleus division once for allat the same time that the pollen tube ger−
minated was escaped by the writer，sinobservanCeu
AC汲NOW‡J耳G署推定ⅣT
The writer expresses his−Tappr・eCiation to Hl・Kuwada・Y・Yamamoto，R・Ogihara who off・ ered valuable sugg・eStion about this study and N”Sugiyama，YuHoriat、Tokyo University whosearched Sax／sliterature for品e，The study was perform6d with the aid of the sul〕Siq diary foundation for・NationalScientific Researchesin the EducationalDepartment of the
Government．
Literatureぐited
lAsami，Y（1927）Pollenabortioninthe shanghaipeachJo軋Sci”AgrSoc29ナ
2い 田aI抽ann，HlT（1952）Pl呼eSSinIeSaIChonoliveeu加ⅠalpIOgI6ふ占い Calij01iveIndusいy News7（3）
3．NakaImura，M（1931）Calyologicalsttldies on the genus RhododendronlJoul‖ Soc・Tropr Agr′ⅠⅠⅠ（1） 4 （1932）Daily changesin the occuIrenCC Of theimpeIject po11en gTainsinImi）aiiens月也Isamina
L・．TouISocけ TIOpAgI‖ⅠⅤ（2）
5，Sax，K，and Ernst CAbbe，（1932）Ch10mOSOme numbers and the anatomy of the secondaIy Xylemin
the OleaceaeJouI．Arnold Arboretum．XIII37−48
摘 要 平井町高橋異郷園内の約10年生Missionは毎年開花するも結実しない。勿寵附近に・他品程が混植 せられ且つ排水も良庵で成育も順調であるに不拘、斯る現象が認められたから、花粉の不発仝に．基 因するものとの推定の許に花粉母細胞に依る核分裂を検鎗し且う染色体数を決定した、犬れと同時 に学内にあるManza坤lo及小豆島オリグ園のNavidillo】∋1anCOの花粉をMissioiQnに交配した 処−㌧最も結実せず、見Missionの花粉を本学のManzanilloに交配した処究仝に結実した点より 推定して花粉砿は異状なきを認めた。 夜分裂には殆ど異状を認めず只Met如haseに於で両極に染色体が引かれる際極僅のプレパラー・ト にて避速を見たのに過ぎないLate Diakinesis及びMetaphaseのpolarviewで明た染色体血妄 23を数へ得た之れはSaxが棋端細胞にて2n＝46を数へ得た結農からしてn＝23一と推定したゎに −⊥・致した。
EXPLANATION OF PLATES
Plate：Ⅰ
11 10
12
PlateI”−Nucleus division of thevaIiety Mission：1，Resting stage”2，SynapsIS Stage‖ 3，Late synapsIS
stagel4，Spiremstage′5，EaIly diakinesis6，Late diakinesis”7，Polar view、Of metaphase 8，Side view of metaphase。9，AnaphasesepaIationl10，Anaphase＄eParationin whichshowslagging・（VeryIaIe）11，Terophase stぞge12，pOlaIView of homotype metaphase‖（1−4，X2，000；5，Ⅹ1，800；6，Ⅹ1，200；7，Ⅹ1，500；8，Ⅹ1・200；
10 11
PlateIIl−1，Side view of homotype metaphasel2，Homotype tezophase 3，MicrospoIein tetrad stage 4，MicIOSPOre Shortly afteI1iheration・5，Cytoplasm with the nuc】eusislocated toward one side and alaIge vacuole occupys the gIeater POrtion of the cellcavlty・I6，Pollen grain showing anincIeaSein cytoplasm contenL 7，Pollen grain previous to the division of nucleus・8，Pollen grainin homotype contIaCtion stage 9，Pollen grain before two day to blossoml10−11，MatuIePO11engrainい（1−2いXll200；3，Ⅹ800；4，Xl，200；
