The seed protein profile of eight taxa of Chili peppers obtained by disc electrophoresis was found to be a diagnostic character in the study of phylogenetic relationships. The distinctness of each species and the wild and cultivated nature of concerned taxa has been confirmed. While the clustering of wildC. annuum var. 'glabriusculum' withC. baccatum types indicated that the former is the progenitor of the latter group, the marked differences discernible in the seed protein profile of all other taxa suggest a polyphyletic origin for the genusCapsicum.

Summary Two F 1 hybrids one between wild C. annuum var glabrisculum and C. frutescens (H 1 ) and another between wild C. annuum var antigua and C. frutescens (H 2 ) were obtained. Cytogenetic analysis of F 1 hybrids showed that the parental genomes differ from each other by 2 or 1 translocations, 1 inversion and some minor structural alterations leading to reduced homologies between the respective parental genomes. Meiotic irregularities pollen and seed sterilities were higher in H 2 than in H 1 . Probable reasons for the differences in respect of their crossability relationships, chromosome pairing and fertilities in non-rearing of reciprocal hybrids are suggested. The role of chromosome structural changes in genome differentiation is suggested. Isolating mechanisms viz., hybrid inviability and hybrid weakness in the reciprocal cross and hybrid sterility in the F 1 hybrids are in operation. Key words Capsicum annuum L., C. frutescens L. interspecific hybrids, Cytogenetics.The genus Capsicum commonly known as chilli pepper, is a major crop and is almost cosmopolitan in distribution. The genus comprises of 5 domesticated and 20 wild species (Anonymous 1983). From the taxanomic standpoint interspecific relationships among them have not been well understood even today. Though cross compatibility relationships among some taxa of this genus have been reported by quite a few workers (Smith and Heiser 1951, Lippert et al. 1966, Ohta 1961, Pickersgill 1971, Venkateswara Rao and Yesoda Raj 1974, Egawa and Tanaka 1984, 1986, Aniel Kumar et al. 1987, 1988 these were mostly confined to the breeding behaviour of the F 1 hybrids. Information on cytogenetic analysis of species hybrids of apsicum is meager (Egawa and Tanaka 1984, Aniel Kumar et al. 1987, 1988. Further, information relating to the cytogenetic behaviour of F 1 hybrids between wild and cultivated species is very meager (Egawa and Tanaka 1984, Aniel Kumar et al. 1988). In view of this, the present study is taken up to elucidate cytogenetic relationships between 2 wild forms of C. annuum and a cultivated form of C. frutescens on the basis of meiotic chromosome pairing, behaviour and fertility of F 1 hybrids and the results are documented in the present communication. Materials and methodsSeeds of 2 wild varieties of C. annuum viz. var, glabrisculum, and var, antigua and cultivar Tabasco of C. frutescens were obtained from. E. Pochard, Monotofavet, Avignon, France. All the 3 accessions were selfed for several generations before these were employed in the hybridization programme. Reciprocal crosses have been attempted by controlled pollinations between each of the 2 varieties of C. annuum with C. frutescens. Hybrids were obtained between C. annuum var glabrisculum and C. frutescens, and C. annuum var antigua and C. frutescens and are referred to as H 1 , H 2 respectively in the text.Young flower buds of the parents and hybrids were fixed in acetic acid and alcohol mixture (1 : 3) and transferred to 70% alcohol after 24 h of fixation. Squashes were made in 2% aceto-

Octoploidy was induced in Chili pepper (Capsicum annuum cultivar 'cerasiformis') through the application of colchicine and the cytomorphological features of two octoploid plants were described. In general, the octoploids did not exhibit gigas characters when compared to the tetraploids; on the contrary they were less vigorous, suggesting that the optimum and desirable ploidy level for Capsicum is probably tetraploid. Chromosome associations such as octovalents and hexavalents, in addition to IVs, IIIs, IIs and Is, were recorded at diakinesis and metaphase I. Meiosis was highly irregular and the pollen and seed fertility was very low. Cytological features of octoploid Chili peppers are compared with octoploids of Physalis and Petunia.

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