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Cucumis melo L. that belongs to Cucurbitaceae family ranks among one of the highest valued horticulture crops being cultivated across the globe. Besides its economical and medicinal importance, Cucumis melo L. is a valuable resource and model system for the evolutionary studies of cucurbit family. However, very limited numbers of molecular markers were reported for Cucumis melo L. so far that limits the pace of functional genomic research in melon and other similar horticulture crops. We developed the first whole genome based microsatellite DNA marker database of Cucumis melo L. and comprehensive web resource that aids in variety identification and physical mapping of Cucurbitaceae family. The Cucumis melo L. microsatellite database (CmMDb: http://65.181.125.102/cmmdb2/index.html) encompasses 39,072 SSR markers along with its motif repeat, motif length, motif sequence, marker ID, motif type and chromosomal locations. The database is featured with novel automated primer designing facility to meet the needs of wet lab researchers. CmMDb is a freely available web resource that facilitates the researchers to select the most appropriate markers for marker-assisted selection in melons and to improve breeding strategies.

Detailed photophysical studies was performed on a series of Cu(I)-responsive fluorescent probes that are based on a 16-membered thiazacrown receptor ([16]aneNS3) tethered to 1,3,5-triarylpyrazoline-fluorophores to determine the possible involvement of Cu(I) in adverse quenching pathways. The combined photophysical, electrochemical, and solution chemistry experiments demonstrated that electron transfer from Cu(I) does not compete with radiative deactivation of the excited fluorophore, indicated that Cu(I)-induced fluorescence switching is kinetically controlled.

Barley is a popular cereal crop of nutritious and industrial importance and there is always a scope to improve a particular crop in view of its value and demand. Spatio-temporal studies discuss the diversity level among the existing varieties as well as the trend of genetic variation over a period of time and are useful in designing suitable strategies for genetic enhancement and improvement of a particular crop. Here, we used SSR markers to assess the level of spatio-temporal genetic diversity among fifty diverse released varieties of barley from India. Spatial diversity (0.233±0.16) was higher in varieties having exotic parentage as compared to the indigenous varieties (0.176±0.18) and significant diversity was also observed among the varieties released from different developing centers. There was a rising trend in % polymorphism and other diversity parameters among the barley varieties released before 1960s to 1970s, which may be attributed to the increasing usage of exotic germplasm during these decades. Increase in temporal diversity from 1970s to 1980s and to 1990s was not much as compared to earlier decades, which suggests that more diverse germplasm should be used to widen the genetic base of barley varieties released over the years. Further, structure and AMOVA results revealed strong differentiation among spatial groups, but not between temporal groups. The role of spatio-temporal genetic diversity studies and the importance of periodic monitoring of the varieties released for further crop improvement was emphasized. [ABSTRACT FROM AUTHOR]

Fungal blast disease is one of the major constraints in finger millet production. Breeding for disease resistance in finger millet, needs characterization of genetic polymorphism among and between the resistant and susceptible genotypes. In total, 67 finger millet genotypes, which are resistant or susceptible to fungal blast disease, were analysed using sequence-related amplified polymorphism (SRAP) and simple sequence repeat (SSR) markers to assess genetic variations and select diverse parents. Twelve each of SRAP and SSR primers produced 95.1 and 93.1% polymorphic bands and grouped them into unweighted pair-group method with arithmetic average clusters. Two of the finger millet genotypes, IE 4709 (blast resistant) and INDAF 7 (susceptible) were distinguished as most diverse genotypes as parents. Several genotype-specific bands observed with SSR primers are potential in developing genotype-specific markers. A high genetic diversity within the resistant and susceptible genotypes, rather than between them, was revealed through Nei's gene diversity (h) index and analysis of molecular variance. The finding helps us to understand the extent of genetic polymorphism between blast disease resistant and susceptible finger millet genotypes to exploit in resistance breeding programs. [ABSTRACT FROM AUTHOR]

Luffa cylindrica (L.) M. Roem. is an underutilized vegetable and a potential biodiesel crop for future. Its fruits are edible and used as vegetable. To aid in the selection of lines for breeding, genetic variation and structure of ten populations of L. cylindrica were determined with three morphological characters and 23 sequence-related amplified polymorphism (SRAP) markers. All the three morphological characters were found diverse among 45 accessions. The SRAP primers produced a total of 177 bands, out of which 129 were polymorphic. Informative markers assessed by different measures (polymorphism information content = 0.18, marker index = 1.26, resolving power = 2.87) will direct the selection of primers for cultivar identification in L. cylindrica. Low level of genetic differentiation among populations and higher level within populations (Gst = 0.4073, Nm = 0.7277, He = 0.124, I = 0.20) was detected that might be due to cross-pollinated nature of L. cylindrica. The clustering pattern obtained through dendrogram and principal coordinate analysis was loosely concordant with the geographical distribution. The Bayesian structure analysis indicated an admixture type of population distribution. The results designate that SRAP and morphological markers are informative for characterization of L. cylindrica and identification of distinctive cultivars. [ABSTRACT FROM AUTHOR]