This review examines recent advances in the induction and development of somatic embryos in leguminous plants. Emphasis has been given to identify the current trends and successful strategies for the establishment of somatic embryogenic systems, particularly in the economically important species. It appears that, in legumes, somatic embryogenesis can be realized relatively easily especially in young meristematic tissues such as immature embryos and developing leaves. In the majority of the species examined, chlorophenoxyacetic acids remained the most active inductive compounds; however, the new generation growth regulators such as thidiazuron are emerging as successful alternatives for high-frequency direct regeneration of somatic embryos, even from well differentiated explant tissues. Low-frequency embryo production, poor germination and conversion of somatic embryos into plantlets and somaclonal variation are the major impediments limiting the utility of somatic embryogenesis for biotechnological applications in legumes. These limitations, however, may be considerably reduced in the near future, as more newly developed growth regulators with specific morphogenic targets become available for experimentation. From the published data, it is apparent that more effort should be given to develop repetitive embryogenic systems with high frequency of germination and regeneration, since such systems will find immediate application in mass propagation and other crop improvement programmes. As our understanding of various morphogenic processes, including growth and differentiation of zygotic embryos, is fast expanding, it is conceivable that development of highly efficient somatic embryogenic systems with practical application can be anticipated, at least for the important leguminous crops, in the foreseeable future.

The biochemical basis of host plant resistance for shoot and fruit borer of brinjal was investigated using selected genotypes from the back crosses involving cultivated brinjal varieties and Solanum viarum. The different levels of biochemical constituents namely peroxidase, poly phenol oxidase, total phenols, and solasodine contents were observed in genotypes derived from inter-specific crosses and their parents. A higher level of polyphenol oxidase activity was observed in interspecific cross F 6 EP65 x S. viarum. There was a clear correlation between the levels of biochemical constituents and shoot and fruit borer incidence. This study showed the biochemical parameters responsible for the resistance but showed as well the development of superior genotypes with resistance to shoot and fruit borer.Prabhu M, Natarajan S, Veeraragavathatham D, Pugalendhi L (2009) The biochemical basis of shoot and fruit borer resistance in interspecific progenies of brinjal (Solanum melongena). EurAsia J BioSci 3, 7, 50-57.

Cucumber, Cucumis sativus (), and melon, Cucumis melo (), are two common vegetable crops worldwide. The present study evaluated eighteen Cucumis accessions (nine C. sativus and nine C. melo) that were collected from three South Asian countries that have the most diversity of Cucumis. Nine quantitative and twenty-three qualitative characteristics were measured. The values of fruit weight displayed the biggest divergence among the nine quantitative traits and much variation was displayed in twenty-three qualitative traits among eighteen accessions. For eight morphological quantitative traits other than fruit weight, eighteen accessions were divided into three groups by using Principle Component Analysis and K-means cluster analysis. Also, two chloroplast genes rbcL and matK of eighteen accessions were sequenced. Combined sequences were subjected to construct phylogenetic trees by Neighbor-Joining and Maximum Likelihood methods. Topologies of nine melon accessions were same in these two methods and nine cucumber accessions showed difference. The genetic distances among each of C. sativus and C. melo accessions were not high. We conclude that the genetic relationship among the eighteen accessions used in this study is not distant although they display significant morphological variations. The information on novel Cucumis germplasms provided here would contribute to breeding program as well as evolutional study in Cucumis.

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Cassava mosaic disease, caused by cassava mosaic geminiviruses are transmitted by Bemisia tabaci. The B. tabaci adults from colonies reared on virus free cassava plant produced from apical meristem culture was studied to determine their ability to transmit Indian cassava mosaic virus (ICMV) and Sri Lankan cassava mosaic virus (SLCMV) from cassava to cassava. Virus free plants were confirmed by polymerase chain reaction (PCR) using geminivirus degenerate primers. The virus acquisition access period (AAP) of 48 h on virus infected cassava leaves and 48 h virus inoculation access periods on virus free healthy leaves were investigated. Both ICMV and SLCMV were absolutely transmitted by whiteflies reared on cassava. Virus specific primers were designed in the replicase region and used to detect virus in B. tabaci after different AAP. The PCR amplified replicase genes from virus transmitted cassava leaves were cloned the plasmid DNA was isolated from a recombinant colony of E. coli DH5α after their confirmation by colony PCR and sequenced them. The nucleotide sequences obtained from automated DNA sequencing were confirmed as ICMV and SLCMV replicase gene after homology searching by BLAST and found to be a new isolates. The nucleotide sequences of new isolates were submitted in GenBank (accession number JN652126 and JN595785).

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