To improve mulberry (Morus spp.) foliage productivity, assessment of relatively underexploited genetic resources is essential. A core panel of 14 mulberry genotypes, shortlisted from 45 lines based on molecular profiling, was screened using random amplified polymorphic DNA (RAPD) and inter simple sequence repeat (ISSR) markers, to assess genetic diversity among them. Out of 25 primers each of RAPD and ISSR screened, 20 polymorphic primers (8 RAPDs and 12 ISSRs) were used in this study. Amplification of genomic DNA of the 14 genotypes, using RAPD analysis, yielded 67 fragments, of which 87.5% were polymorphic. The number of amplified fragments ranged from 6 to 11, with the size of amplicons ranging from 300 to 1,300 bp. The 12 ISSR primers produced 106 bands across 14 genotypes, of which 93% were polymorphic. The number of amplified fragments ranged from 5 to 12, with the size of amplicons ranging from 200 to 1,100 bp. Similarity coefficient ranged from 0.29 to 0.90 for RAPD and 0.36 to 0.81 for ISSR. For RAPDs the polymorphic information content (PIC) values ranged from 0.280 to 0.496, with an average of 0.351. For ISSRs, the PIC values ranged from 0.325 to 0.428, with an average of 0.375. There was a slight difference between RAPDs and ISSRs in their average resolving power (Rp). Using unweighted pair group method with arithmetic mean (UPGMA), a process of hierarchical clustering by Numerical Taxonomy and Multivariate Analysis System (NTSYSpc), RAPD-, and ISSR-derived results were grouped the 14 genotypes into 2 and 5 clusters, respectively. Principal coordinate analysis also showed gross similarities with UPGMA-based dendrograms, with minor deviations. Morus indica L. (C-2016) exhibited highest divergence in cluster and lowest similarity coefficient value. This identified elite line may be utilized in mulberry improvement programs. The RAPD and ISSR markers were successfully used in assessing the genetic diversity among the tested mulberry genotypes. ARTICLE HISTORY

Bacterial leaf spot incited by Xanthomonas campestris pv. mori is a devastating foliar disease of mulberry reported globally. Host plant resistance is the most sustainable and economic control measure but so far unexplored. Highly heterozygous plant behaviour and scant genetic information of bacterial leaf spot resistance limits a targetted breeding approach in mulberry. In the present research eight pseudo-F 2 (F 1 )full-sib progenies derived from selected resistant and susceptible sources were evaluated symptomatically for bacterial leaf spot resistance under natural disease occurrence in 2008 and 2009. Significant variation for bacterial leaf spot resistance was observed in the parents and progenies. Broad sense heritability estimate (0.9) indicates that selection of resistant genotypes can be useful for exploitation in future advanced breeding programs for mulberry. High narrow sense heritability estimates (0.76) [2008] and (0.79)[2009] suggest additive gene effects for the disease resistant trait. The continuous frequency distribution of diseases severity across the progenies indicates that bacterial leaf spot resistance in mulberry may be inherited quantitatively.

BackgroundSilkworm fecal matter is considered one of the richest sources of antimicrobial and antiviral protein (substances) and such economically feasible and eco-friendly proteins acting as secondary metabolites from the insect system can be explored for their practical utility in conferring broad spectrum disease resistance against pathogenic microbial specimens.Methodology/Principal FindingsSilkworm fecal matter extracts prepared in 0.02 M phosphate buffer saline (pH 7.4), at a temperature of 60°C was subjected to 40% saturated ammonium sulphate precipitation and purified by gel-filtration chromatography (GFC). SDS-PAGE under denaturing conditions showed a single band at about 21.5 kDa. The peak fraction, thus obtained by GFC wastested for homogeneityusing C18reverse-phase high performance liquid chromatography (HPLC). The activity of the purified protein was tested against selected Gram +/− bacteria and phytopathogenic Fusarium species with concentration-dependent inhibitionrelationship. The purified bioactive protein was subjected to matrix-assisted laser desorption and ionization-time of flight mass spectrometry (MALDI-TOF-MS) and N-terminal sequencing by Edman degradation towards its identification. The N-terminal first 18 amino acid sequence following the predicted signal peptide showed homology to plant germin-like proteins (Glp). In order to characterize the full-length gene sequence in detail, the partial cDNA was cloned and sequenced using degenerate primers, followed by 5′- and 3′-rapid amplification of cDNA ends (RACE-PCR). The full-length cDNA sequence composed of 630 bp encoding 209 amino acids and corresponded to germin-like proteins (Glps) involved in plant development and defense.Conclusions/SignificanceThe study reports, characterization of novel Glpbelonging to subfamily 3 from M. alba by the purification of mature active protein from silkworm fecal matter. The N-terminal amino acid sequence of the purified protein was found similar to the deduced amino acid sequence (without the transit peptide sequence) of the full length cDNA from M. alba.

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