Sugarcane is a C4 and agro-industry-based crop with a high potential for biomass production. It serves as raw material for the production of sugar, ethanol, and electricity. Modern sugarcane varieties are derived from the interspecific and intergeneric hybridization between Saccharum officinarum, Saccharum spontaneum, and other wild relatives. Sugarcane breeding programmes are broadly categorized into germplasm collection and characterization, pre-breeding and genetic base-broadening, and varietal development programmes. The varietal identification through the classic breeding programme requires a minimum of 12–14 years. The precise phenotyping in sugarcane is extremely tedious due to the high propensity of lodging and suckering owing to the influence of environmental factors and crop management practices. This kind of phenotyping requires data from both plant crop and ratoon experiments conducted over locations and seasons. In this review, we explored the feasibility of genomic selection schemes for various breeding programmes in sugarcane. The genetic diversity analysis using genome-wide markers helps in the formation of core set germplasm representing the total genomic diversity present in the Saccharum gene bank. The genome-wide association studies and genomic prediction in the Saccharum gene bank are helpful to identify the complete genomic resources for cane yield, commercial cane sugar, tolerances to biotic and abiotic stresses, and other agronomic traits. The implementation of genomic selection in pre-breeding, genetic base-broadening programmes assist in precise introgression of specific genes and recurrent selection schemes enhance the higher frequency of favorable alleles in the population with a considerable reduction in breeding cycles and population size. The integration of environmental covariates and genomic prediction in multi-environment trials assists in the prediction of varietal performance for different agro-climatic zones. This review also directed its focus on enhancing the genetic gain over time, cost, and resource allocation at various stages of breeding programmes.

Sheath rot disease caused by Sarocladium oryzae is an emerging threat for rice cultivation at global level. However, limited information with respect to genomic resources and pathogenesis is a major setback to develop disease management strategies. Considering this fact, we sequenced the whole genome of highly virulent Sarocladium oryzae field isolate, Saro-13 with 82x sequence depth. The genome size of S. oryzae was 32.78 Mb with contig N50 18.07 Kb and 10526 protein coding genes. The functional annotation of protein coding genes revealed that S. oryzae genome has evolved with many expanded gene families of major super family, proteinases, zinc finger proteins, sugar transporters, dehydrogenases/reductases, cytochrome P450, WD domain G-beta repeat and FAD-binding proteins. Gene orthology analysis showed that around 79.80 % of S. oryzae genes were orthologous to other Ascomycetes fungi. The polyketide synthase dehydratase, ATP-binding cassette (ABC) transporters, amine oxidases, and aldehyde dehydrogenase family proteins were duplicated in larger proportion specifying the adaptive gene duplications to varying environmental conditions. Thirty-nine secondary metabolite gene clusters encoded for polyketide synthases, nonribosomal peptide synthase, and terpene cyclases. Protein homology based analysis indicated that nine putative candidate genes were found to be involved in helvolic acid biosynthesis pathway. The genes were arranged in cluster and structural organization of gene cluster was similar to helvolic acid biosynthesis cluster in Metarhizium anisophilae. Around 9.37 % of S. oryzae genes were identified as pathogenicity genes, which are experimentally proven in other phytopathogenic fungi and enlisted in pathogen-host interaction database. In addition, we also report 13212 simple sequences repeats (SSRs) which can be deployed in pathogen identification and population dynamic studies in near future. Large set of pathogenicity determinants and putative genes involved in helvolic acid and cerulenin biosynthesis will have broader implications with respect to Sarocladium disease biology. This is the first genome sequencing report globally and the genomic resources developed from this study will have wider impact worldwide to understand Rice-Sarocladium interaction.

Sugarcane is a trans-seasonal long-duration crop and tillering phase (60–150 days) is the most sensitive phase for moisture stress, causing significant reduction in biomass accumulation. The study focussed to assess the Genotype × Environment Interaction (GEI) for tillering phase moisture stress and to identify the stable genotypes in sugarcane. The study dealt with 14 drought tolerant genotypes and two standards (Co 86032 and CoM 0265) which were evaluated in two plant and one ratoon trials at four locations in Maharashtra, India. The moisture stress was imposed for 60 days from 90 to 150 days after planting and corresponded to tillering phase by withholding the irrigation. The AMMI ANOVA showed significant GEI for cane and CCS yield accounting 18.33 and 19.45 percent of variability respectively. Drought and genotype main effects were highly significant accounting 49.08 and 32.59 percent variability for cane yield and, 52.45 and 28.10 percent variability for CCS yield respectively. The first two interactive principal component (IPCA) biplots of AMMI showed diverse nature of all four environments and the DiscriminativevsMean biplots of Genotype + genotype × environment interaction (GGE) model showed that ‘Pune’ as the highly discriminating environment. The genotype ranking biplots of GGE showed that Co 85019 was the most stable genotype followed by Co 98017. Similar results were also observed in YieldvsIPCA1 biplot of AMMI, which revealed Co 85019 and Co 98017 as high yielding stable varieties. Yield related environmental maximum (YREM) showed thirteen and nine percent loss due to crossover interactions in Co 85019 for cane yield and CCS yield respectively. The multi-environment BLUP and genotype stability index (GSI) has reaffirmed that Co 85019 as a drought proof and stable genotype with high yield under tillering phase drought stress. The results suggested using Co 85019 for cultivation in drought prone regions and the usefulness of the methodology for identifying more such sugarcane varieties for the benefit of resource poor famers in drought affected regions.

The phosphate transporter (PHT) family of proteins plays an imperative role in regulating phosphorus (P) acquisition as well as in translocation from the soil into cells and organs. Phosphorus is an essential macronutrient required for plant life that is not readily available to crops, and resources are diminishing rapidly because of the huge needs of global agriculture. In this study, 23 ShPHT genes were identified in the sugarcane (Saccharum spp.) genome through a comprehensive genome-wide in silico analysis. Phylogeny, gene structure, and conserved motif analysis of PHT genes in sugarcane (ShPHTs) indicated five subfamilies (PHT1-4 and PHO1 subfamily). Gene ontology (GO) analysis revealed that the ShPHT genes were largely involved in phosphate ion transport, phosphate starvation, stimulus response, stress response, and symporter activity. Gene expression analysis under salinity stress confirmed strong induction of PHT genes in wild genotype sugarcane (IND99-907). PHT1-1, PHT1-2, and PHT1-3 members were notably up-regulated in roots under salt stress. The upstream region of PHT genes contained PHR1-binding sites (P1BS), MYB-type, and WRKY- type binding elements. Overall, the present study paves the way for a deeper understanding of the evolution of sugarcane PHT genes and their role in salinity and Pi stress tolerance in sugarcane.

Erianthus arundinaceus[Retzius] Jeswiet, a wild relative of sugarcane has a high biomass production potential and a reservoir of many genes for superior agronomic traits and tolerance to biotic and abiotic stresses. A comparative physiological, anatomical and root transcriptome analysis were carried out to identify the salt-responsive genes and metabolic pathways associated with salt-tolerantE. arundinaceusgenotype IND99-907 and salinity-sensitive sugarcane genotype Co 97010. IND99-907 recorded growth of young leaves, higher proline content, higher relative water content, intact root anatomical structures and lower Na⁺/K⁺, Ca²⁺/K⁺and Mg²⁺/K⁺ratio as compared to the sugarcane genotype Co 97010. We have generated four de novo transcriptome assemblies between stressed and control root samples of IND99-907 and Co 97010. A total of 649 and 501 differentially expressed genes (FDR<0.01) were identified from the stressed and control libraries of IND99-907 and Co 97010 respectively. Genes and pathways related to early stress-responsive signal transduction, hormone signalling, cytoskeleton organization, cellular membrane stabilization, plasma membrane-bound calcium and proton transport, sodium extrusion, secondary metabolite biosynthesis, cellular transporters related to plasma membrane-bound trafficking, nucleobase transporter, clathrin-mediated endocytosis were highly enriched in IND99-907. Whereas in Co 97010, genes related to late stress-responsive signal transduction, electron transport system, senescence, protein degradation and programmed cell death, transport-related genes associated with cellular respiration and mitochondrial respiratory chain, vesicular trafficking, nitrate transporter and fewer secondary metabolite biosynthetic genes were highly enriched. A total of 27 pathways, 24 biological processes, three molecular functions and one cellular component were significantly enriched (FDR≤ 0.05) in IND99-907 as compared to 20 pathways, two biological processes without any significant molecular function and cellular components in Co 97010, indicates the unique and distinct expression pattern of genes and metabolic pathways in both genotypes. The genomic resources developed from this study is useful for sugarcane crop improvement through development of genic SSR markers and genetic engineering approaches.