Artemisia obtusiloba Ledeb. collected near the confluence of the Katun River and the Chuya River, Mt. Altai (50°23′38″, 26°40′39″) showed the hexaploid chromosome number and karyotype of K(2n=54)=36m+10st+8st^sat. The plants of this population have not shown to be sympatric with any members of the Chrysanthemum fruticulosum complex. Thus, the present chromosome number and karyotype of Artemisia obtusiloba from Altai Mts. were different from those of the individual plants collected in Wu Chuan County, Inner Mongolia Autonomous Region, the People′s Republic of China.

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Lysimachia mauritiana displayed a comprehensive karyotypic polymorphism (18 cytotypes) in the Ryukyu Archipelago of Japan. To explore chromosome variation on Takarajima Island, karyomorphological analysis was made in 238 individuals from six localities throughout the island. Total five different chromosome numbers (2n=16, 17, 18, 19, 20) and 11 cytotypes were recognized in the area. In the localities of the island, multiple cytotypes coexisted and diversified every year among and within population, although populational coexistence of plural cytotypes was maintained. Especially, three cytotypes of 16 (6m), 17 (5m) and 18 (4m) co-occurred in every locality, indicating that they were involved in a formation of cytotypes in Takarajima Island.

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Gonospermum fruticosum (C. Smith ex Link) Less, Argyranthemum coronopifolium (Willd.) Humphries and two strains of A. foeniculaceum (Willd.) Webb ex Schultz-Bipl all placed in the family Asteraceae, the tribe Anthemideae, were collected in Tenerife, the Canary Islands, Spanish Territory, Africa. They were analyzed in order to clarify their relationships and variabilities by karyotypes and molecular ISSR (inter simple sequence repeat). Gonospermum fruticosum and Argyranthemum coronopifolium studied showed the common karyotype different from that of two strains of A. foeniculaceum. Among the 54 ISSR bands obtained in the four species studied 46 were polymorphic, and 22 were species-specific. Gonospermum and Argyranthemum showed quite different band patterns from each other. Two strains of A. foeniculaceum showed different, large polymorphic patterns. Thus, the ISSR must be useful tool to isolate and evaluate intergeneric, interspecific, down to intraspecific genic differences, furthermore, introgressive hybridization within the members of the tribe Anthemideae, the Asteraceae.

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Cytological and genetical behaviors of two desynaptic plants induced from Capsicum annuum L. var. G4 by methyl methane sulphonate treatment have been studied. In these two plants, desynapsis was assumed due to homozygous induction. Analysis of chromosomal behavior at different stages of meiosis has been thoroughly accomplished in the desynaptic plant. At diakinesis in one plant univalents and bivalents were present while in other multivalents along with univalents and bivalents were also noticed. Bivalents were randomly distributed in one plant while non-random in the other. Abnormalities like univalents, irregular distribution of chromosomes, laggards and micronuclei were also observed at metaphase, anaphase and telophase respectively. Meiotic studies revealed that sterility was due to irregular chromosome pairing but the genetic data indicated that sterility was because of single recessive gene in homozygous condition. The desynaptics obtained during the present investigation fit into the medium strong type.

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Morus L. an economically important genus has more than 60 species distributed in both the Hemispheres. Chromosome number varies from 2n=28 to 2n=308 with ploidy level from x to 22x. In the present investigation two tetraploid mulberry varieties namely, Morus cathyana and M. macroura have been analyzed for detailed meiotic studies. Based on the chromosome configuration and other meiotic behaviour x = 14 has been considered as basic number of the genus. Meiosis was irregular. Various anomalies like univalents, bivalents, trivalents and quadrivalents are associated with nucleolus at diakinesis. Tetra, tri and bivalents in addition to univalents are noticed in metaphase I. Unequal separation of chromosomes are observed in anaphase I and II. Laggards and precocious movement of chromosomes at metaphase II and unoriented chromosomes at anaphase II have been observed.

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Meiotic studies, chromosome pairing and chiasma frequency were performed on 12 species of Chrysanthemum (Asteraceae). All the species studied are based on x=9, the commonest base number of the genus. The present record of 2n=36 for C. maximum is a new tetraploid cytotype for the species. C. koreanum (2n=54) and C. paludosum (2n=18) are the two species studied cytologically for the first time. Chromosomal counts on Indian accessions of species viz. C. coccineum, C. indicum, C. multicaule, C. pyrethrum and C. segetum are made for the first time. Chiasma frequency ranges from 1.80-1.99 per bivalent in diploids, 2.47-3.01 per bivalent in tetraploids and 1.37 in hexaploid. Multivalents are noticed in both diploids and tetraploids.

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