Morphological, anatomical and isozyme variability among taro (Colocasia esculenta) accessions from southeastern part of Central Java, Indonesia

Pitoyo A, Prameta AA, Marsusi, Suratman, Suranto. 2018. Morphological, anatomical and isozyme variability among taro (Colocasia esculenta) accessions from southeastern part of Central Java, Indonesia. Biodiversitas 19: 1811-1819. The objective of this study was to evaluate morphological, anatomical and isozyme variability among taro accessions from southeastern part of Central Java (Indonesia). A total of 20 taro accessions were collected from a wide range of sites during field surveys. Morphological characters measurements were taken on vegetative structures such as roots, stems, leaves, and corms. Anatomical characters were observed from both paradermal and transverse sections of leaf. Identification of biochemical markers was done by using peroxidase and esterase isozyme system. A UPGMA dendrogram among accessions was constructed based on the genetic similarity matrix by applying a cluster analysis using a computer programme, NTSYS Version 2.00. The analysis of variance for morphological and anatomical characters revealed that there was significant difference for majority of the tested traits indicating that there was a variability among the taro accessions. Polymorphism was observed using isozymes of esterase (12 banding pattern) and peroxidase (8 banding pattern). Based on the dendrogram at a level of 62 % similarity, taro accessions were segregated into two major clusters. In Cluster I, the closest relationship was shown between SKH and SKA accessions that had 96 % coefficient of similarity. The ten accessions from Klaten, Sragen, and Karanganyar were then clustered separately as Cluster II with coefficient of similarity 73.52 %.

Morphological and Isozyme Variation in Natural Populations of the Genus Medicago L. Prospected in Northern Algeria

As part of the evaluation and enhancement of genetic resources, morphological and isozyme variability within and among 169 accessions, representing 14 species of the genus Medicago L. collected in northern Algeria, was assessed using twelve quantitative traits and two enzymatic systems. Phenotype frequencies were scored in six enzyme zones to determine isozyme variability within and among populations. The data analysis resolved a high level of genetic diversity. Ten morphometric characteristics contributed to the discrimination of the species. The relationship between the collection site environment and phenotypic characteristics was also studied. Esterase (EST) enzyme system was more polymorphic than glutamate oxaloacetate transaminase (GOT) system. Were scored 2 zones with 10 bands and 21 phenotypes for GOT (glutamate oxaloacetate transaminase) and 4 zones with 22 bands and 71 phenotypes for EST (esterase) Polymorphism index and Jaccard’s genetic distances revealed the existence of a high genetic diversity within and among the studied populations. The annual species M. polymorpha presented an intraspecific polymorphism index of 0.57, which was higher than all other species indices. Clustering of the species based on isozyme markers was in agreement with taxonomic criteria and showed no significant correlation with morphological characteristics. Conservation programs should take into account the level of genetic diversity within and between populations revealed by isozyme markers.

Tissue distribution of esterase isozymes and their responses to cypermethrin in three macrobrachium species

In recent times prawn grounds are getting contaminated with an increased use of agricultural pesticides. Esterases play an intermediary role in conferring or in contributing to insecticide resistance. Hence, Esterase isozyme variability was studied in three Macrobrachium species (M. rosenbergii, M. malcolmsonii and M. lamarrei) on 7.5% PAGE with ? and ? naphthyl acetate as substrate in terms of number of bands, staining intensity and toxicity effects. Expression of esterase isozymes was studied in five different tissues (eye, muscle, nerve cord, stomach and hepatopancreas) where four esterase bands (Est-1, Est-2, Est-3 and Est-4) were observed in M. rosenbergii and M. lamarrei and two bands (Est-1 and Est-4) in M. malcolmsonii. Bands in the hepatopancreas of M. rosenbergii, in the eye of M. lamarrei and in the nerve cord of M. malcolmsonii were highly intense indicating higher esterase activity. It was also noticed that the slowest bands with higher molecular weight were more expressed than the others and spreading area of a particular band was not fixed in all the tissues. To observe the impact of insecticide on esterases all five tissues were exposed to 1000 ppm of cypermethrin for 24 hours and was subjected to PAGE, it was found that treated samples showed less esterase expression. Only the muscle tissues from three species were exposed to a range of doses (0.078-1000 ppm), species specific fluctuation of esterase activity was observed in an irregular fashion. Bioassay conducted with cypermethrin on M. lamarrei indicated that LC50 was 0.05ppm at 2 hours. Fluctuation of esterase activity was observed with time and dose concentrations in post mortal electrophoretic assay. DOI: http://dx.doi.org/10.3329/jasbs.v38i2.15614 J. Asiat. Soc. Bangladesh, Sci. 38(2): 227-235, December 2012

Variability of Anthoxanthum species in Poland in relation to geographical-historical and environmental conditions: isozyme variation

Variation of 9 isozyme systems was studied in Polish populations of 3 species of the genus Anthoxanthum: the native A. odoratum s. str. L. and A. alpinum Á. Löve & D. Löve, as well as the alien A. aristatum Boiss. Results of this study show that A. odoratum is characterized by a high isozyme variability of lowland populations, weakly correlated with habitat type, and partial genetic distinctness of montane populations. Moreover, 5 isozyme markers have been identified (Pgi-2, Dia-2, Mdh, Idh, Pgm) for the allopolyploid A. odoratum. Populations of A. aristatum are highly polymorphic (P = 98%). The observed isozyme differentiation of its populations (FST = 0.087) is low and gene flow between them (Nm = 5.314) is high. The genetic variation reflects environmental variation only to a small extent and is not significantly related to the phase of chorological expansion of this species. Altitudinal vicariants, A. alpinum and A. odoratum, are characterized by morphological and isozymatic distinctness, indicating their reproductive isolation. In populations of A. alpinum, polymorphism is high (P = 76.92%), differentiation among populations is moderate (FST = 0.198), and gene flow between populations along the altitudinal transect (Nm = 1.709) is relatively low

Comparison of Esterase Isozyme Variability in Some Selected Tissues of the Asian and African Catfishes (Siluriformes: Clariidae)

Variation in esterase isozymes expression of 19 different tissues of the Asian catfish (Clarias batrachus) and African catfish (C. gariepinus) was studied. These tissues were: liver, anterior muscle, mid muscle, tail muscle (ventral region), tail muscle (tip region), buccal muscle, stomach, foregut, midgut, hindgut, kidney, gill, heart, eye (lens), eye (black portion), pelvic muscle, fore-, mid- and hind-brain. Maximum five esterase bands, viz. Est-11.83, Est-21.50, Est-31.15, Est-41.00 and Est- 50.17 were observed in the Asian catfish and four bands, viz. Est-21.50, Est-31.15, Est-41.00 and Est-50.17 in the African catfishes. Tissue specific localization of the isozymes was observed in both Asian and African catfishes. Comparatively higher esterase activity was found in digestive tissues. Higher number of esterase bands was found in C. batrachus which seems to be an indication of its greater allelic variation in esterases than those in the C. gariepinus. DOI: http://dx.doi.org/10.3329/bjz.v40i1.12893 Bangladesh J. Zool. 40(1): 43-50, 2012