JPCS Vol(3) ● Oct-Dec 2011 www.arpapress.com/Volumes/JPCS/Vol3/JPCS_3_04.pdf

EPIDERMAL MICROMORPHOLOGY OF SPECIES IN THE GENUS MOENCH .S. MOORE (COMPOSITAE) IN NIGERIA

Kemka, C.I.1 & Nwachukwu, C.U.2

Department of Biology, Alvan Ikoku Federal College of Education Owerri, Imo State, Nigeria

ABSTRACT Detailed studies on eight Crassocophalum species ( biafrae, C. montuosum, C. mannii, C. crepidioides C. vitellinum, C. rubens, C.togoense and C. sarcobasis) found in Nigeria, which are important leaf vegetables were undertaken with the aid of a microscope to ascertain their taxonomic relationship. The micromorphological features discovered include the hypostomatic distribution of stomata in C. mannii while the other species had hypoamphistomatic. Sinuous anticlinal wall was present on adaxial (upper) surfaces of C. togoense and C.crepidioides, the clusters of trichomes on mid-vein of the adaxial surfaces of C.vitellinum and C. crepidioides.The high density of trichomes on the veins of the adaxial surface of C.mannii is of taxonomic interest and could be used to demilit the taxon from the other species. C.vitellinum, C.crepidioides and C. togoense which are densely hairy could also be delimited from C.biafrae and C.montuosum that are sparsely hairy.A mixture of sinuous and straight-arcuate anticlinal wall was present in both the abaxial and adaxial surfaces of all crassocephalum species studied except in C.togoense and C.crepidioides that has sinuous anticlinal wall in both adaxial and abaxial surfaces.

Keywords. Crassocephalum , Micromorphology, Epidermis,Adaxial,Abaxial.

1. INTRODUCTION The genus Crassocephulum Moench S. Moore is a member of the tribe in Compositae () family. The family is cosmopolitan in distribution and in West Africa contains about 84 genera and 288 species (Gill, 1988). The members of the genera are mostly herbs and rarely shrubs. Crassocephalum is represented by twenty four species in Tropical Africa ( Bosch, 2004 ) and fifteen species in West Africa in which ten species have been recorded in Nigeria (Hutchinson and Dalziel, 1963). Crassocephalum, which is in the same tribe as Emilia, have their involucral bracts being in only one series (Olorode, 1984).The species of the genus Crassocephalum are of various economic values. C. crepidioides is a herb often cultivated in Sourthern Nigeria and are used as vegetables. In Kenya donkeys are reported to browse C. montuosum and in (Tanganyika) Tanzania the is used for treating infected eyes.The importance of epidermal characters in general and those of trichome in particular has been widely recognized in angiospermic taxonomic consideration by workers such as (Ogundipe, 1992),(Nwachukwu and Edeoga, 2006) in eight species of Indigofera Leguminosae- Papilionideae. (Mbagwu, Nwachukwu and Okoro, 2008) in two species of Solanum (Solanaceae),(Edeoga and Ikem 2001) in three species of Boerhevia (Nyctaginaceae). According to them majority of the flowering can readily be identified with as much ease by their vegetative characters as by their floral structure.Considering the various uses of Crassocephalum plants and the paucity of information on the epidermal studies, this paper therefore describes the epidermal micromorphological characters of species in the genus Crassocephalum

2. MATERIALS AND METHODS Fresh and mature leaves were collected from randomly selected plants of species studied. The specimens were fixed in F.A.A. (formalin acetic acid alcohol mixture) for 48 hours to ensure that the cells are possibly maintained as near to life and improve the contrast. Herbarium materials were first boiled for about 10 minutes to soften it before fixing them. After 48 hours the fixed materials were rinsed with distilled water and soaked in 5% commercial bleach (Sodium Oxochlorate II (Nacl) for about 20 minutes to lubricate and soften the tissues of the leaves. The surface to be examined was placed on a glass slide while the other surface was carefully scraped with a razor blade. The clear epidermal layers obtained were then washed in several changes of distilled water, stained in 1% safranin – 0 for about 1 minute and temporary mounted in aqueous glycerol solution.

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JPCS Vol(3) ● Oct-Dec 2011 Kemka & Nwachukwu ● Species in the Genus Crassocephalum

3. RESULTS The epidermal cell and stomatal characteristics of the taxa investigated are shown in Tables 1 and 2. The taxa studied showed sinuous anticlinal walls on all the abaxial surfaces. (Plates 9,10,11,12,13,and 14). Sinuous anticlinal wall also occurred on the adaxial surfaces of C. togoense and C. crepidioides (Plates 3 and 8). The anticlinal wall is straight to arcuate on the adaxial surfaces of C. mannii, C. biafrae, C. vitellinum, C. montuosum and C. crepidioides (Plates 1, 2, 3, 4, 5, 6, 7 and 8). Cuticular striations appeared on the abaxial surfaces of C. montuosum C. vitellinum and C. crepidioides. There are four to five epidermal cells around the stomata on both the adaxial and abaxial surfaces in all the species studied. The distribution of the stomata is hypoamphistomatic in all the species except C. mannii which is hypostomatic. Contiguous stomata were found in the abaxial and adaxial surface of all the taxa studied viz. C. biafrae, C. montuosum, C. mannii, C. crepidioides C. vitellinum, C. rubens, C.togoense and C. sarcobasis. Anomocytic stomata were found on both adaxial and abaxial surfaces of all the species studied. Anisocytic stomata were found on the adaxial surface of C. vitellinum, C. biafrae and C. sarcobasis.

TRICHOMES: Simple unbranched, non glandular trichomes occurred on all the taxa studied. The occurrence is more on the abaxial surfaces than the adaxial surface. The mid-vein of the adaxial surfaces of C. mannii showed clusters of these simple unbranched non-glandular trichomes. In terms of density of the trichomes, the results indicated that C. vitellinum, C. crepidioides, C. sarcobasis and C. togoense are densely hairly while C. biafrae and C. montuosum are sparsely hairy.

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JPCS Vol(3) ● Oct-Dec 2011 Kemka & Nwachukwu ● Species in the Genus Crassocephalum

TABLE 1: EPIDERMAL CELL CHARATERISTCIS OF THE CRASSOCEPHALUM SPECIES STUDIED Character Epidermal Anticlinal Epidermal Cell Length Epidermal Cell No. of Co.ef. Cell Shape Cell Wall Width Epidermal of Species Cells variability C. mannii Abaxial Surface Irregular Sinuous 37.70 ± 3.40 37.15 ±1.41 1088 6.12 8.27 Adaxial Surface Irregular Straight-arcuate 36.99 ± 1.84 31.59 ± 3.47 5.04 11.17 C. biafrae Abaxial Surface Irregular Sinuous 39.81 ± 3.50 29.25 ± 1.22 Adaxial Surface Irregular Straight-arcuate 1950 59.67 ± 6.84 31.68 ± 5.06 6.46 C. crepidioides 2040 7.25 Abaxial Surface Irregular Sinuous 4.74 Adaxial Surface Irregular Sinuous 41.49 ± 2.71 31.41 ± 1.20 8.92 960 C. montuosum Abaxial Surface Irregular Sinuous 55.53 ± 1.51 29.07 ± 2.05 1.92 1570 6.58 Adaxial Surface Irregular Straight-arcuate 49.07 ± 2.05 15.84 ± 0.93 2.72 C. vitellinum 7.07 Abaxial Surface Irregular 48.40 ± 1.41 20.78 ± 6.90 1576 4.32 Adaxial Surface Irregular Sinuous 2784 7.10 32.04 ± 3.45 19.08 ± 0.69 C. rubens Straight-arcuate 3.57 Abaxial Surface Irregular 2570 3.20 56.97 ± 6.74 31.68 ± 5.07 Adaxial Surface Irregular Sinuous 5.27 4334 8.07 C. sarcobasis Straight-arcuate 39.54 ± 1.25 20.17 ± 0.70 Abaxial Surface Irregular 11.83 56.05 ± 2.16 32.46 ± 3.51 6.71 Adaxial Surface Irregular Sinuous 860

C. togoense Straight-arcuate 31.54 ± 3.36 17.82 ± 0.76 4.82 Abaxial Surface Irregular 2750 6.78 36.05 ± 2.15 31.05 ± 3.40 Adaxial Surface Irregular Sinuous 6.65 1076 8.72 Sinuous 27.49 ± 2.07 15.16 ± 0.86

2572 5.15 32.64 ± 3.45 19.45 ± 1.46 9.20

4.44 777 8.26

1080 5.28 7.07

3.32 6.15

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JPCS Vol(3) ● Oct-Dec 2011 Kemka & Nwachukwu ● Species in the Genus Crassocephalum

TABLE 2: STOMATAL CHARATERISTCIS OF THE CRASSOCEPHALUM SPECIES STUDIED Character Stomatal µm µm Co.ef. Stomatal Index type Stomatal Stomatal Width of var (%) Species Length C. mannii Abaxial Surface Anomocytic 24.64 ± 1.25 10.26 ± 0.54 1.32 2.68 4.86 Adaxial Surface Contiguous - - - None - 27.45 ± 0.40 24.82 ± 1.58 1.51 C. biafrae 1.92 Abaxial Surface Contiguous Anomocytic 27.63 ± 1.36 13.77 ± 0.82 1.45 3.95 Adaxial Surface Contiguous

Anomocytic 3.00 C. crepidioides 27.08 ± 1.20 26.65 ± 1.29 Abaxial Surface 4. 84 Contiguous 4.50 1.87 Anomocytic 16.65 ±1.25 Adaxial Surface 27.90 ± 1.29 4.64 Contiguous 7.50 1.87

C. montuosum Anomocytic 17.15 ± 1.31 Abaxial Surface 38.00 ± 1.90 4.24 1.06 7.15 Adaxial Surface Contiguous 20.97 ± 1.50 31.46 ± 1. 14 3.45 7.30 1.15 C. vitellinum Anomocytic Abaxial Surface 27.18 ± 4.39 31.86 ± 1.10 1.26 3.45 Adaxial Surface Contiguous 7.15 27.63 ± 1.36 13.77 ± 0.82 Anomocytic 3.37 C. rubens 4.92 Abaxial Surface Contiguous 5.99 27.16 ± 1.86 24.64 ± 1.47 Anomocytic 1.08 2.86 Adaxial Surface 15.77 ± 0.76 Contiguous 25.72 ±1.68 2.68 C. sarcobasis Abaxial Surface Anomocytic 1.65 24.56 ±1.38 5.92 Contiguous 26.06 ±1.82 1.15 Adaxial Surface Anomocytic 1.92 14.64 ± 0.85 5.86 20.65 ± 1.32 C. togoense Contiguous 3.70 Anomocytic 27.63 ± 1.22 Abaxial Surface 1.86 29.13 ±1.20 4.92 Contiguous Adaxial Surface Anomocytic 17.86 ± 1.53 14.26 2.70 9.07 25.13 ± 1.76 Contiguous

Anomocytic 4.67 7.88 Contiguous

Anomocytic

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JPCS Vol(3) ● Oct-Dec 2011 Kemka & Nwachukwu ● Species in the Genus Crassocephalum

Fig 1: Adaxial epidermis of C. mannii X 250

Fig 2: Adaxial epidermis of Crassocephalum biafrae X 250

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JPCS Vol(3) ● Oct-Dec 2011 Kemka & Nwachukwu ● Species in the Genus Crassocephalum

Fig 3: Adaxial epidermis of Crassocephalum crepidiodes X 250

Fig 4: Adaxial epidermis of Crassocephalum montuosum X 260

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JPCS Vol(3) ● Oct-Dec 2011 Kemka & Nwachukwu ● Species in the Genus Crassocephalum

Fig 5: Adaxial epidermis of Crassocephalum vitellinum X 150

Fig 6: Adaxial epidermis of Crassocephalum rubens X 150

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JPCS Vol(3) ● Oct-Dec 2011 Kemka & Nwachukwu ● Species in the Genus Crassocephalum

Fig 7: Adaxial epidermis of Crassocephalum sarcobasis X 150

Fig 8: Adaxial epidermis of Crassocephalum togoense X 250

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JPCS Vol(3) ● Oct-Dec 2011 Kemka & Nwachukwu ● Species in the Genus Crassocephalum

Fig 9: Abaxial epidemis of Crassocephalum biafrae X 250

Fig 10: Abaxial epidermis of Crassocephalum crepidiodes X 150

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JPCS Vol(3) ● Oct-Dec 2011 Kemka & Nwachukwu ● Species in the Genus Crassocephalum

Fig 11: Abaxial epidermis of Crassocephalum montuosum X 250

Fig 12: Abaxial epidermis of Crassocephalum vitellinum X 150

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JPCS Vol(3) ● Oct-Dec 2011 Kemka & Nwachukwu ● Species in the Genus Crassocephalum

Fig 13: Abaxial epidermis of Crassocephalum sarcobasis X 150

Fig 14: Abaxial epidermis of Crassocephalum togoense X 150

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JPCS Vol(3) ● Oct-Dec 2011 Kemka & Nwachukwu ● Species in the Genus Crassocephalum

Fig 15: Adaxial epidermis of C. mannii showing clusters of Trichomes at the mid vein. X 250

4. DISCUSSION Hutchinson and Dalziel (1963) used only gross macro morphological features to classify different species in the genus Crassocephalum. However, results from the present studies shows that data from other lines of taxonomic evidence are needed for a more reliable, clear and comprehensive classification of the taxa. Thus information from micro morphology, have giving more detailed and modern data upon which a broad-based classification may be used. Stomatal characteristics such as the type, distribution, size and index are among the anatomical parameter used in plant . The hypostomatic distribution of stomata in only C. mannii out of all the species studied is of taxonomic importance and could be used to delimit the taxon. The other species showed hypoamphistomatic distribution. The occurrence of contiguous stomata on abaxial surfaces of all the species studied shows that they are related despite their variation in other features. The anisocytic stomata on the adaxial surface of C. biafrae, C. vitellinum, C. sarcobasis could be used for delimitation of the taxa. Anomocytic stomata occurred on both surfaces of all the species except C. mannii. The sinuous anticlinal wall of the epidermal cells of adaxial surfaces of C. togoense and C. crepidioides is of diagnostic importance. Epidermal cell length among the species studies range from 31.54 ± 3.36 in C.sarcobasis to 49.07 + 2.05 in C. montuosum Trichomes (hairs) are epidermal features common to stems, leaves and other aerial organs; their high taxonomic value has long been appreciated.In all the species studied simple unbranched trichomes occurred but there exist variation in the distribution, density and length of the trichomes. Olowokudejo (1990) used trichome size and density to delimit West African genus Annona (Annonaceae) into 7 taxa. The high density of trichomes on the veins of the adaxial surface of C. mannii and its very low density on the other epidermal cells on the same adaxial surface is of taxonomic interest and could be used to delimit the taxon from the other species. C. vitellinum, C. crepidioides, C. sarcobasis and C. togoense which are densely hairy could also be delimited from C. biafrae and C. montuosum that are sparsely hairy.

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JPCS Vol(3) ● Oct-Dec 2011 Kemka & Nwachukwu ● Species in the Genus Crassocephalum

5. CONCLUSION Modern taxonomy leans very heavily on multiple characters rather than on single character, owning to the importance of epidermal characters, this study has made it clear that the presence of stomata on only the abaxial surface of C.mannii of diagnostic value. The occurrence of simple unbranched trichomes in the eight species studied viz C. biafrae, C. vitellinum, C. sarcobasis, C. crepidioides, C. montuosum, C. togoense, C. rubens and C. mannii showed that they are related. However the variation in the density, distribution and length of the trichomes could be used to delimit one taxon from each other.

6. REFERENCES [1]. Bosch, C. H (2004). Crassocephalum rubens ( Juss .ex Jacq. ) S.Moore In Grubben.G.J.H & Dentor, O.A (Editors) PROTA 2: Vegetables / Legumes [CD- ROM] PROTA, Wageningen Nertherlands. [2]. Edeoga,H.O and Ikem C.I (2001). Comparative Morphology of leaf epidermis in three species of Boerhevia L J Econ Tax Bot 19:197-205 [3]. Gill, L.S. (1988): Taxonomy of Flowering Plants. African Fep Publishers Ltd. Nig.p. 246 [4]. Hutchinson, J. and Dalziel, M. (1963). Floral of West Tropical Africa. Crown agent, London Vol. 2:243 – 246 [5]. Mbagwu,F .N, Nwachukwu,C.U and Okoro,O.O Comparative Leaf Epidermal Studies on Solanum macrocarpon and Solanum nigrum. Research Journal of Bot. 3 (1): 45-48. [6]. Nwachukwu, C.U. and Edeoga H.O.(2006). Morphology of the leaf Epidermis in certain species of Indigofera L. (Leguminosae – Papilionoideae) Int. J.4: 40=43. [7]. Ogundipe, O.T. (1982). Leaf Epidermal studies in Genus Datura Linn (Solanaceae) Phytomorphology 42: 209 – 217. [8]. Olorode, O. (1984). Taxonomy of West African Flowering Plants. University of Ife Press, Nigeria. Pp. 112- 114. [9]. Olowokudejo, J.D (1990) Comparative Morphology of Leaf Epidermis in the Genus Annona (Annonaceae) in West Africa. Phytomorphology. 40:407 – 422.

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