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Twenty nine germplasm lines of Chenopodium quinoa and two of Chenopodium berlandieri subsp. nuttalliae were evaluated for 12 morphological and 7 quality traits for two test seasons. The 19 traits were analyzed for cluster and principal component analysis. The first four PCs contributed 78.70 % of the variability among the germplasm lines. The first PC accounted for 39.5% of the variation and had inflorescence/plant, plant height and stem diameter as the traits with largest coefficients, all with positive sign. The characters with greatest positive weight on PC 2 were days to maturity (0.309), inflorescence length (0.260) and branches/plant. All the germplasm lines were grouped into six clusters based on average linkage method. Cluster III had high values for seed yield and most of the quality traits but showed a small seed size. The dendrogram separated the two lines of C. berlandieri subsp. nuttalliae from the quinoa lines.

Fusarium wilt in bananas is one of the most devastating diseases that poses a serious threat to the banana industry globally. With no effective control measures available to date, biological control has been explored to restrict the spread and manage the outbreak. We studied the effective biological control potential of different Trichoderma spp. in the management of Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4). Expression of the defense related genes and metabolites in banana plants inoculated with Foc TR4 and treated with effective Trichoderma sp interactions were also studied. The in vitro growth inhibition of Foc TR4 by Trichoderma reesei isolate CSR-T-3 was 85.19% indicating a higher antagonistic potential than other Trichoderma isolates used in the study. Further, in in vivo assays, the banana plants treated with the isolate CSR-T-3 T. reesei had a significant reduction in the disease severity index (0.75) and also had increased phenological indices with respect to Foc TR4 treated plants. Enhanced activity of defense enzymes, such as β-1, 3-glucanase, peroxidase, chitinase, polyphenol oxidase, and phenylalanine ammonia lyase with higher phenol contents were found in the Trichoderma isolate CSR-T-3 treated banana plants challenge-inoculated with Foc TR4. Fusarium toxins, such as fusaristatin A, fusarin C, chlamydosporal, and beauveric acid were identified by LC-MS in Foc TR4-infected banana plants while high intensity production of antifungal compounds, such as ß-caryophyllene, catechin-o-gallate, soyasapogenol rhamnosyl glucoronide, peptaibols, fenigycin, iturin C19, anthocyanin, and gallocatechin-o-gallate were detected in T. reesei isolate CSR-T-3 treated plants previously inoculated with Foc TR4. Gene expression analysis indicated the upregulation of TrCBH1/TrCBH2, TrXYL1, TrEGL1, TrTMK1, TrTGA1, and TrVEL1 genes in CSR-T-3 treatment. LC-MS and gene expression analysis could ascertain the upregulation of genes involved in mycoparasitism and the signal transduction pathway leading to secondary metabolite production under CSR-T-3 treatment. The plants in the field study showed a reduced disease severity index (1.14) with high phenological growth and yield indices when treated with T. reesei isolate CSR-T-3 formulation. We report here an effective biocontrol-based management technological transformation from lab to the field for successful control of Fusarium wilt disease caused by Foc TR4 in bananas.

Mango (Mangifera indica L.) is known as the 'king of fruits' for its rich taste, flavor, color, production volume and diverse end usage. It belongs to plant family Anacardiaceae and has a small genome size of 439 Mb (2n = 40). Ancient literature indicates origin of cultivated mango in India. Although wild species of genus Mangifera are distributed throughout South and South-East Asia, recovery of Paleocene mango leaf fossils near Damalgiri, West Garo Hills, Meghalaya point to the origin of genus in peninsular India before joining of the Indian and Asian continental plates. India produces more than fifty percent of the world's mango and grows more than thousand varieties. Despite its huge economic significance genomic resources for mango are limited and genetics of useful horticultural traits are poorly understood. Here we present a brief account of our recent efforts to generate genomic resources for mango and its use in the analysis of genetic diversity and population structure of mango cultivars. Sequencing of leaf RNA from mango cultivars 'Neelam', 'Dashehari' and their hybrid 'Amrapali' revealed substantially higher level of heterozygosity in 'Amrapali' over its parents and helped develop genic simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers. Sequencing of double digested restriction-site-associated genomic DNA (ddRAD) of 84 diverse mango cultivars identified 1.67 million high quality SNPs and two major sub-populations. We have assembled 323 Mb of the highly heterozygous 'Amrapali' genome using long sequence reads of PacBio single molecule real time (SMRT) sequencing chemistry and predicted 43,247 protein coding genes. We identified in the mango genome 122,332 SSR loci and developed 8,451 Type1 SSR and 835 HSSR markers for high level of polymorphism. Among the published genomes, mango showed highest similarity with sweet orange (Citrus sinensis). These genomic resources will fast track the mango varietal improvement for high productivity, disease resistance and superior end use quality.