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Evolutionary tracks for 2–8 M⊙ stars, with metallicities of Z = 0.014, 0.006, and 0.002, including rotation, are computed with Modules for Experiments in Stellar Astrophysics (MESA). We study how rotation impacts the evolutionary properties of classical Cepheids. We examine whether rotation can offer a plausible explanation for the mass discrepancy problem when it is included in the evolutionary code using the fully diffusive approximation for rotationally induced mixing processes. We find that rotation barely influences the appearance and luminosity levels of the blue loops. While luminosity increases with increasing initial rotation rate, the increase does not exceed 0.04 dex, a fraction of the increase resulting from including the main-sequence (MS) core overshooting of 0.2Hp. As a consequence, rotation alone cannot resolve the mass discrepancy problem without simultaneously requiring significant MS core overshooting. Similar to the mass–luminosity relation, the period–radius and period–luminosity relations are barely affected by rotation, while the period–age relation predicts Cepheid ages to be only a few percent longer compared with models without rotation. The predicted surface rotational velocities are too large compared with observations. These results are in contrast with those obtained with the Geneva code, which implements rotational mixing using the advective–diffusive scheme. In that approach, the luminosity levels of the loops are significantly higher, their luminosity extent increases, and the predicted rotation velocities are lower compared with MESA models. The differences between the two approaches arise from significantly more efficient rotation-induced mixing during the MS evolution in models computed with the advective–diffusive scheme.

Rice is a global food grain crop for more than one-third of the human population and a source for food and nutritional security. Rice production is subjected to various stresses; blast disease caused by Magnaporthe oryzae is one of the major biotic stresses that has the potential to destroy total crop under severe conditions. In the present review, we discuss the importance of rice and blast disease in the present and future global context, genomics and molecular biology of blast pathogen and rice, and the molecular interplay between rice–M. oryzae interaction governed by different gene interaction models. We also elaborated in detail on M. oryzae effector and Avr genes, and the role of noncoding RNAs in disease development. Further, rice blast resistance QTLs; resistance (R) genes; and alleles identified, cloned, and characterized are discussed. We also discuss the utilization of QTLs and R genes for blast resistance through conventional breeding and transgenic approaches. Finally, we review the demonstrated examples and potential applications of the latest genome-editing tools in understanding and managing blast disease in rice.

Powdery mildew is one of the serious diseases of garden pea which causes a large number of yield losses. Genetic resistance is quite effective, being cost-effective and environment friendly than fungicide applications. In the present studies an initial attempt has been made to identify resistant genotypes against powdery mildew disease developed from hybridization followed by validation of the disease. The experimental material comprised of 48 genotypes that includes 44 advanced breeding lines was evaluated for powdery mildew incidence in Randomized Complete Block Design with three replications at two locations under field conditions [Palampur (winter 2017–18 and 2018–19) and Kukumseri (summer 2018)] and in vitro at Palampur [detached leaf method and polyhouse conditions]. Ten lines viz., SP7, SN-1, SN-6-1, SN-7-1, SN-2, SN-5-2, SN-6-2, SN-10, SN-21 and SP-281 showed resistant reaction along with check Palam Sumool while 27 lines were identified as moderately resistant in comparison to susceptible check Azad P-1. Besides, six lines namely, SP-2, SP-5, SP-10, SP-24, SA-4 and SP-12-1 gave moderately susceptible reaction along with checks Pb-89 and Palam Priya. Only, SP-19 was categorized as susceptible. The high yielding lines SP-3, SP-6 and SP-22 showed moderately resistant reaction in both natural and artificial conditions. Validation of resistance using molecular markers revealed that neither the parental genotypes nor the progenies possess the er1 gene of JI1559. The er2 linked marker ScOPX-17 1700 was polymorphic between Palam Sumool and Palam Priya but the marker didn’t show polymorphism between er2 harboring line (JI2480). These results suggested that the lines showing resistance under field conditions may have some other genes or alleles for resistance and further confirmation is needed by developing mapping populations with specific gene or gene combinations.

Evolutionary tracks for 2–8 M⊙ models, covering a [Fe/H] = −1.0 (Z = 0.0014) to [Fe/H] = +0.2 (Z = 0.02) metallicity range, are computed with Modules for Experiments in Stellar Astrophysics, MESA, to investigate evolutionary and pulsation properties of classical, fundamental mode Cepheids. We examine in detail the effects of convective overshooting from the main-sequence core, as well as from the convective envelope on the red giant branch. Mass loss is also included in a few model sets. Linear pulsation properties are derived consistently with a module of MESA, Radial Stellar Pulsation, RSP. We provide edges of the classical instability strip, as well as ages, crossing times through the instability strip, and period-change rates. Period–luminosity, mass–luminosity, period–radius, and period–age relations are provided, both in analytical and tabular form. Their dependence on metallicity, crossing number, and overshooting parameters are investigated. Qualitative comparisons with classical Cepheids in the Milky Way and Magellanic Clouds as well as other theoretical relations are presented. We find satisfactory agreement for most of the observables and good matches with other theoretical work; however, reproducing short-period Cepheids in the Small Magellanic Cloud as well as Cepheid mass discrepancy poses a challenge for the presented models. Considering the metallicity effect of the period–luminosity relation, we find γ ≈ −0.20 mag dex−1, nearly independent on photometric pass band and in good agreement with recent observational studies. The magnitude of this effect depends on the underlying mass–luminosity relation, being stronger for relations that predict higher luminosities at a given mass.

Rice blast caused by Magnaporthe oryzae is one of the most important diseases of rice. Pi54, a rice gene that imparts resistance to M. oryzae isolates prevalent in India, was already cloned but its avirulent counterpart in the pathogen was not known. After decoding the whole genome of an avirulent isolate of M. oryzae, we predicted 11440 protein coding genes and then identified four candidate effector proteins which are exclusively expressed in the infectious structure, appresoria. In silico protein modeling followed by interaction analysis between Pi54 protein model and selected four candidate effector proteins models revealed that Mo-01947_9 protein model encoded by a gene located at chromosome 4 of M. oryzae, interacted best at the Leucine Rich Repeat domain of Pi54 protein model. Yeast-two-hybrid analysis showed that Mo-01947_9 protein physically interacts with Pi54 protein. Nicotiana benthamiana leaf infiltration assay confirmed induction of hypersensitive response in the presence of Pi54 gene in a heterologous system. Genetic complementation test also proved that Mo-01947_9 protein induces avirulence response in the pathogen in presence of Pi54 gene. Here, we report identification and cloning of a new fungal effector gene which interacts with blast resistance gene Pi54 in rice.

KEY MESSAGE : A set of NILs carrying major blast resistance genes in a Basmati rice variety has been developed. Also, the efficacy of pyramids over monogenic NILs against rice blast pathogen Magnaporthe oryzae has been demonstrated. Productivity and quality of Basmati rice is severely affected by rice blast disease. Major genes and QTLs conferring resistance to blast have been reported only in non-Basmati rice germplasm. Here, we report incorporation of seven blast resistance genes from the donor lines DHMASQ164-2a (Pi54, Pi1, Pita), IRBLz5-CA (Pi2), IRBLb-B (Pib), IRBL5-M (Pi5) and IRBL9-W (Pi9) into the genetic background of an elite Basmati rice variety Pusa Basmati 1 (PB1). A total of 36 near-isogenic lines (NILs) comprising of 14 monogenic, 16 two-gene pyramids and six three-gene pyramids were developed through marker-assisted backcross breeding (MABB). Foreground, recombinant and background selection was used to identify the plants with target gene(s), minimize the linkage drag and increase the recurrent parent genome (RPG) recovery (93.5–98.6 %), respectively, in the NILs. Comparative analysis performed using 50,051 SNPs and 500 SSR markers revealed that the SNPs provided better insight into the RPG recovery. Most of the monogenic NILs showed comparable performance in yield and quality, concomitantly, Pusa1637-18-7-6-20 (Pi9), was significantly superior in yield and stable across four different environments as compared to recurrent parent (RP) PB1. Further, among the pyramids, Pusa1930-12-6 (Pi2+Pi5) showed significantly higher yield and Pusa1633-7-8-53-6-8 (Pi54+Pi1+Pita) was superior in cooking quality as compared to RP PB1. The NILs carrying gene Pi9 were found to be the most effective against the concoction of virulent races predominant in the hotspot locations for blast disease. Conversely, when analyzed under artificial inoculation, three-gene pyramids expressed enhanced resistance as compared to the two-gene and monogenic NILs.

In the present study, we introgressed two genes each governing resistance to major diseases of rice namely, bacterial blight (BB) (xa13 and Xa21) and blast (Pi2 and Pi54) into a popular Basmati cultivar, Pusa Basmati 1509 (PB 1509) through marker assisted backcross breeding (MABB). Through foreground selection, seven plants homozygous for all the four genes were selected from a large population of 1832 BC2F2 plants and subjected to background selection coupled with phenotypic selection for agronomic and grain quality traits of the recurrent parent. BC2F2 selections were further advanced to BC2F4 generation to develop near-isogenic lines (NILs). Six NILs from the BC2F4 families with an RPG recovery ranging from 82.5% to 90.5% were evaluated in multi-location trials for agronomic performance, grain quality traits and disease resistance. The level of resistance to BB and blast diseases in all the selected NILs was similar to that of the donor parent. Three BB races, race 2, 4 and 6, respectively produced on average 1.8, 2.3 and 2.5 cm of lesion length in the NILs as against 15.6, 18.1 and 20.8 cm in PB1509. Further, the NILs recorded a disease score of 1.0 and 1.7 for two blast isolates Mo-nwi-38 and Mo-nwi-kas, respectively, as against the score of 4.0 in PB 1509 for both the isolates. The NILs were similar to PB 1509 for major agronomic and grain quality traits with the advantage of resistance to BB and blast diseases.

Background With its adapted microbial diversity, the phyllosphere contributes microbial metagenome to the plant holobiont and modulates a host of ecological functions. Phyllosphere microbiome (hereafter termed phyllomicrobiome) structure and the consequent ecological functions are vulnerable to a host of biotic (Genotypes) and abiotic factors (Environment) which is further compounded by agronomic transactions. However, the ecological forces driving the phyllomicrobiome assemblage and functions are among the most understudied aspects of plant biology. Despite the reports on the occurrence of diverse prokaryotic phyla such as Proteobacteria, Firmicutes, Bacteroides, and Actinobacteria in phyllosphere habitat, the functional characterization leading to their utilization for agricultural sustainability is not yet explored. Currently, the metabarcoding by Next-Generation-Sequencing (mNGS) technique is a widely practised strategy for microbiome investigations. However, the validation of mNGS annotations by culturomics methods is not integrated with the microbiome exploration program. In the present study, we combined the mNGS with culturomics to decipher the core functional phyllomicrobiome of rice genotypes varying for blast disease resistance planted in two agroclimatic zones in India. There is a growing consensus among the various stakeholder of rice farming for an ecofriendly method of disease management. Here, we proposed phyllomicrobiome assisted rice blast management as a novel strategy for rice farming in the future. Results The tropical \"Island Zone\" displayed marginally more bacterial diversity than that of the temperate ‘Mountain Zone’ on the phyllosphere. Principal coordinate analysis indicated converging phyllomicrobiome profiles on rice genotypes sharing the same agroclimatic zone. Interestingly, the rice genotype grown in the contrasting zones displayed divergent phyllomicrobiomes suggestive of the role of environment on phyllomicrobiome assembly. The predominance of phyla such as Proteobacteria, Actinobacteria, and Firmicutes was observed in the phyllosphere irrespective of the genotypes and climatic zones. The core-microbiome analysis revealed an association of Acidovorax, Arthrobacter, Bacillus, Clavibacter, Clostridium, Cronobacter, Curtobacterium, Deinococcus, Erwinia, Exiguobacterium, Hymenobacter, Kineococcus, Klebsiella, Methylobacterium, Methylocella, Microbacterium, Nocardioides, Pantoea, Pedobacter, Pseudomonas, Salmonella, Serratia, Sphingomonas and Streptomyces on phyllosphere. The linear discriminant analysis (LDA) effect size (LEfSe) method revealed distinct bacterial genera in blast-resistant and susceptible genotypes, as well as mountain and island climate zones. SparCC based network analysis of phyllomicrobiome showed complex intra-microbial cooperative or competitive interactions on the rice genotypes. The culturomic validation of mNGS data confirmed the occurrence of Acinetobacter, Aureimonas, Curtobacterium, Enterobacter, Exiguobacterium, Microbacterium, Pantoea, Pseudomonas, and Sphingomonas in the phyllosphere. Strikingly, the contrasting agroclimatic zones showed genetically identical bacterial isolates suggestive of vertical microbiome transmission. The core-phyllobacterial communities showed secreted and volatile compound mediated antifungal activity on M. oryzae. Upon phyllobacterization (a term coined for spraying bacterial cells on the phyllosphere), Acinetobacter, Aureimonas , Pantoea , and Pseudomonas conferred immunocompetence against blast disease. Transcriptional analysis revealed activation of defense genes such as OsPR1.1 , OsNPR1, OsPDF2.2 , OsFMO, OsPAD4, OsCEBiP , and OsCERK1 in phyllobacterized rice seedlings. Conclusions PCoA indicated the key role of agro-climatic zones to drive phyllomicrobiome assembly on the rice genotypes. The mNGS and culturomic methods showed Acinetobacter, Aureimonas, Curtobacterium, Enterobacter, Exiguobacterium, Microbacterium, Pantoea, Pseudomonas, and Sphingomonas as core phyllomicrobiome of rice. Genetically identical Pantoea intercepted on the phyllosphere from the well-separated agroclimatic zones is suggestive of vertical transmission of phyllomicrobiome. The phyllobacterization showed potential for blast disease suppression by direct antibiosis and defense elicitation. Identification of functional core-bacterial communities on the phyllosphere and their co-occurrence dynamics presents an opportunity to devise novel strategies for rice blast management through phyllomicrobiome reengineering in the future. Graphical abstract

Dactylorhiza hatagirea (D. Don) Soo, family Orchidaceae is an endangered medicinal herb inhabiting higher altitudes of western Himalayas. Due to reckless exploitation for its roots, it is of high conservation concern. In the present study fifteen microsatellites were developed and characterized across twenty collections of D. hatagirea. The total numbers of alleles amplified by these microsatellites were 64 with an average of 4.2 alleles per marker. Average observed and expected heterozygosity values for polymorphic loci were 0.623 and 0.631, respectively. Mean polymorphism information content value of the polymorphic markers was 0.532. Of the fourteen polymorphic microsatellites, 7 deviated from Hardy–Weinberg equilibrium. Microsatellites reported here can be utilized to address questions related to genetic characteristics in this species.

Plants respond to water scarcity by modifying transcription and metabolite accumulation; however, mechanisms leading to drought tolerance/sensitivity in chickpea ( Cicer arietinum L.) are poorly understood. To understand the molecular basis of drought tolerance/sensitivity, the carbohydrate content and transcriptional changes in the genes of sugar, starch, abscisic acid (ABA), and gibberellic acid pathways were studied in a drought-tolerant genotype (ICC 8950) and a drought-sensitive genotype (ICC 3776). Droughts disrupted carbohydrate metabolism in ICC 3776, leading to decrease in starch content and increase in sugar content, including sucrose. In ICC 8950, under drought stress, the starch content remained unchanged but sugar levels increased slightly. The reduction in starch content in ICC 3776 resulted from increased degradation rather than decreased synthesis, whereas in ICC 8950, starch anabolism as well as catabolism genes were downregulated, leading to unchanged starch levels. The increase in sucrose content in ICC 3776 under drought stress resulted from lower degradation due to the downregulation of cell wall invertase. The expression of ABA catabolism genes under drought increased in ICC 3776 but decreased in ICC 8950, suggesting increased ABA content in ICC 3776 but not in ICC 8950. This study showed that drought causes a decrease in the starch content and an increase in the sucrose and ABA contents in the drought-sensitive genotype, whereas the drought-tolerant genotype maintains starch and sucrose levels coupled with lower ABA.