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BULL. BOT. SURV. INDIA Vol. 4, Nos. 14: pp. 27-38, 1W CYTOTAXONOMY OF AMARYLLIDACEAE Cytogenctics Labmatmy, Dcwtmcnt of Botany, Cakutta Uni~wsiy,Calcutta-19 ABSTRACT Chromosome numbers are now known for about 46 genera in the family Amaryllidaceae. The lowest basic number has been found to be 5 and the highest 30. Besides these two, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 19, 23 and 29 have also been encountered of which 11 is found in majority oc the genera. In a number of genera the derivation of one basic number from the other bas been established. In the genus Allium largest nu*er of species have been studied cytologically. The nert,largest is Narcissus followed by <ephpnthes, Crhum, Hif&astrum and Lyaris in that order. B or supernumerary chromosomes have been observed in Agnpanthq Allim, Crinum, -aa Haemanthus, Hippcmtrum, Ljcoris and ~arcisms. In this family repatterning of chromosomes through inversions (both para ahd pericentric), translocation, polypbidy (eu-, aneuo-, hetero-, auto-, and allopolyploidy) and hybridization hwr: pla ed prominent role in chromosome number evolution, karyotype alteration and speciation. In ad&tion to this, gene mutation has also pla ed significant puf in speciation. Ready vegetative propagation has helped in maintaining sterile KYbrids and thole forms with numerical md smi?Wa\ changes of chromosomes. Apomixis has also been responsible in chromosome number evolution m some genera. A consideration of taxonomic work done in Amaryllidaceae points out that Hutchinson's system of classification, based on the umbellate inflorescence rather than on the pajition of. the wary, ha been found to be more ph logenetic but the amendments proposed by several workers for ahangm in tribal and generic level could be taken into consideration and in some cases may be justified, INTRODUCTION of small chromosomes, yet the former was placed in Liliaceae and the latter in Amaryllidaceae by The family Amaryllidaceae is very interesting earlier taxonomists, On the basis df their cytologk from cytotaxonomic point of view. Cytologically, 'most of the species belonging to this family hare cal findings the7 urged for keeping. them togeiher, small number of large chromosomes and somi: In Hutchinsons classification these two genera species of the genus Allium are being extensively have been put together in Agavaceae. The genus Fureraen, which has cytolo$cal similarities used for experimental studies involvin physical (Whitaker, 1934) with Yucca an Agave, has also and chemical agents. Taxonomical~y, t1 e family has attracted added im ortance since the delimita- been grouped with these two genera by Hutchinson An'derson (rgqo, ede Lawrence, 19~1)on the tion of the famil by Rutchinson (1g34, 1959) to of only those mem gers of petaloid monocotyledons, basis of his studies on the floral anatomy whlch have umbellate inflorescence. Liliales approved of Hutchinson's inclusion of Agapantheae, and Allieae in Amaryllidaceac. Cheadle (1942)also accepted the inclusion of Aga- CYTOTAXONOMIG CONSIDERATION pantheae, Allieae and Glllieseae in Amaryllidaceae on the basis of his anatomical work on mono- Hutchinson radically changed the concept of cotyledons. Maia (1941, vide Lawrence, ~ggl) the differentiation of Liliaceae and. ~maryllida- through his studies on the pollen grab of .some Feae formerly based on the position of ova'ky and monocotyledons also came to the same conclueion, recognized the importance of the umbellate type of Lawrence (1951) commented that the classification inflorescence as the unifyin ptinciple in Amarylli- based on the position of the ovary was not constant, daceae. For this reason, {e included the tr~bes since in the genera Ophiopogon, Bomareae and Agapantheae, Gilliesieae and Allieae in Amarylli- Hemerocallis of Liliaceae both su rior and inferior daceae, which were formerly placed in Liliaceae. ovaried plants are found apd F=or this reason he On the other hand, he excluded the tribes expressed the opinion that the classification of Hy~xideae,Alstromerieae, Agaveae, Vellozieae and Hutchinson, which was based on the type of in- Gnostyleae &om Amaryllidaceac. H~tchiison's florescence, was or more fundamental imporranp classification has been more or less su ported by and stable in nature. Flory and Yarnell (193 ) gave taxonomists and in many instances eviJ? ences have an account of chromosome numbers in the fEmero- been brought forward by anatomists and cytologists callideae, Alstromerialeo, and Amaryllidales follow* to su port him. As for example, Mckelvey and ing Hutchiison's classification but they supported Sax pn333). Whitaker (19%) and Granick ('MI pointed out that Yucca and Agme are quite similar cytologically in having 5 pairs of large and 25 .pairs 28 BULLETIN OF THE BOT'AMCAL SURVEY OF INDIA [VO~.4 Stout's (1932) view that so far as the basic Traub's (1957) system, basic numbers of chromo- number is concerned the genuc Hemerocallis does somes were also taken into account in the subfamily, not fit in Liliaceae, since it has a n number of r I, tribal and generic level. Later on, Bose (1958~) while an allied genus Hbsta has a basic number of commented on the taxonomic positions of the 30. On this ground they thought that further cyto- genera Sprekeliu and I,ycoris in the light of his cy~ taxonomic study of some genera in Amaryllidaceae logical findings. might: call for an inclusion of Hemerocallis in The above discussion shows that although Hut- Amaryllidaceae. Earlier, Whitaker (1934) and chiison's (1934) new system of classification based Granick (1944) removed the genus Hosta from on t$e umbellate inflorescence rather than on the Hemerocalleae and placed ,~tin the family position of the ovary has been found to be a more Agavaceae. natural system, the amendments proposed by several Sato (1942) observed that his results of karyotype workers for shifting tribes and genera could be taken analyses in different genera of Liliaceae and related into consideration and in some cases may be families agreed with Hutchinson's (1934) system of justified. classification. He pointed out that the karyotypes of some genera in Liliaceae and Amaryllidaceae BASIC NUMBERS IN THE FAMILY AhfARYLLIDACEAE were similar in morphology, which according t& In the genus Allium largest number of species in him, showed that Hutchinson's classification based the .family Amaryllidaceae have been studled cyto- on the umbellate inflorescence was more reason- logically. The next largest is Narcissus, followed by able than that based on the position of ovary.. Zephyranthes, CTinum, Hippeastrum and Lycoris Through his studies on the karyotypes of in order. As regards the chro'mosome numbers, Phormizrm, Hosta, Hemerocallis, Leucocrinurn, Table I shows that very varied chromosome num- Hespe~ocallis,Dracaena and Cordyline he supported bers have been reported from Alliurn, Zephyranthes, Hutchinson's opinion that the Amaryllidaceae Hymenocallis and some other genera. might have originated from the tribe Hemero- A glance at Table I will also show that in this callideae of Liliaceae. Sato (1942) agreeing with family the lowest basic number i's 5, and the highest Hutchinson, also suggested the transference of is 30. Besides these two, there are n=6, 7, 8, g, 10, Alstroemerieae into Liliaceae but su ported Nakai's I I, 12, 14, IS, 16, 19,23 and 29, of which I I is found , (vide Sato 1942) modification o!! Hutchinson's in majority of genera. In a number of genera the Later, Flory (I~M)gave another list of derivation of one basic number from the other has cTtern* romosome numbers in Hemerocallideae, Alstroe- been established, as for example, Fernandes (1946) meriales, and Amaryllidales basing on Hutchinson's has shown that the basic number ,I% in Narcissus, classification but took into account the changes is derived from n=7, while in a genus like Lycorisj suggested by some workers. Sharma . and Ghosh 6 or 1 I could be taken as the orignal basic number, not only supported the removal of the tribe although Inariyama (1g51b) has favoured I I as thk oxideae from Amaryllidaceae by Hutchinson original basic number on .the basis of fusion of rod but also accepted his creatlon of the family chromosomes. On the. other hand, if the frag- Hgpxidaceae. ' Mookerjea (1955) found cytological mentation of V chrornos~mesis taken into consi- corroboration of Hutchrnson's systtm in Amarylli- deration then '6 would be the original basic number daceae? and later, working with some members in Lycoris. This aspect will be taken up in detail of Liliaceae, Mookerjea (1956) did not agree to in the following discussion. his inclusion of Funkia in Hemerocalleae. Traub' 19~7)~while supporting the delimitation of the MECHANISM OF CHROMOSOME NUMBER EVOLU- by Hutchinson, proposed some new changes TION, KARYOTYPE ALTERATION AND SPECIATfON and presented a classification of the family IN AMARYLLIDACEAE Am Ilidaceae,.which was'a third revision of their In Amaryllidaceae repatterning of chromosomes (~rax,1938 and Traub and Moldenke, 1949, vide through inversions (both ~araand pericentric) and Traub, 1957) earlier classifications. On the .basis translocation, polyploid? (eu-, aneuq hetero-, of morphological and cytological similarities with auto-, and aHopolyploidy) and hybridization have; members of the tribe Allieae, A pantheae and played prominent role in chromosome number Gllliesiae, he removed the tribe Eemerocallideae evolution, karyotype alteration and speciation. Sato from Liliaceae and placed it in Amaryllidaceae. He (1938) and others have discussed the importance of also divided