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Generally, it is believed that sugarcane grows normally in the absence of stalk infecting pathogens causing red rot, wilt, smut or fungal diseases. Although degeneration occurs in sugarcane due to systemic build-up of non-fungal pathogens, the canes are harvested as healthy canes. The degenerated canes showed 30–50% reduction in cane weight and also a similar loss in juice yield. Even though physiological yield potential of sugarcane is more than 300 t/ha, an average cane yield of only 84 t/ha is achieved in India. Yield gap due to the degeneration caused by the non-fungal pathogens, especially viruses associated with mosaic and yellow leaf disease, ratoon stunting bacterium and grassy shoot phytoplasma are ignored under field conditions. Improved molecular diagnostics combined virus elimination through meristem culture showed a practical approach to manage varietal rejuvenation in sugarcane and demonstrated restoration of yield potential of major varieties. The industry should realize this major impact to sugarcane and take corrective measures to sustain the cane cultivation in India.

Sugarcane is traditionally cultivated in India since time immemorial to extract gur and Khandsari sugar. In the country, white sugar manufacturing started ~ 300 years ago the with imported Saccharum officinarum genotypes. After 1850s, sugar industry expanded rapidly and such expansion also led to emergence of new threats in the form of red rot caused by the dreaded fungal pathogen Colletotrichum falcatum. The new threat caused production losses in the then Presidencies of Madras, Bombay and Bengal. Sugarcane Breeding Institute (SBI) was established in 1912 to breed sugarcane varieties for red rot resistance with other desirable agronomical traits. The institute achieved commercial success by releasing the first interspecific hybrid variety Co 205 during 1918 and release of many such varieties to the subtropical region revolutionized sugarcane cultivation by improved cane yield leading to attaining self-sufficiency in sugar requirement. Although the new varieties sustained the boom, red rot started attacking the elite varieties in different decades through a series of epidemics. These epidemics hindered sugarcane cultivation for a while in different states; however after each epidemic, new varieties were deployed to counter the disease onslaught and saved sugar industry from the brink. Many superior varieties with red rot resistance have benefitted the industry, but evolution of new C. falcatum pathotypes caused breakdown of resistance and made the life of many elite varieties short-lived. In the recent decades, variation in C. falcatum was characterized, designated into new pathotypes, and new pathotypes were used for red rot screening. The historical red rot epidemics in the country over the decades resembled to ‘boom and bust cycle’ reported in cereal rust diseases. Domination of single variety combined with flood during monsoon seasons/waterlogging favoured red rot epidemics. Notwithstanding red rot epidemics, red rot-resistant varieties played a vital role to manage the disease and to sustain sugarcane cultivation in India for more than 100 years.

Colletotrichum falcatum Went causing red rot in sugarcane has gained a very high virulence in the sub-tropical India by evolving into a virulent pathotype CF13. The disease spread has reached 100% in several thousand hectares during the past few seasons. Reasons for such massive spread of the disease in the states of Uttar Pradesh and Bihar were investigated under field conditions. Observations on disease development in the affected canes revealed infections from soil, sett, water and air. However, more than 58% of the affected canes exhibited infections from aerial route as midrib lesions and the disease progressed from spindle to canes. Although sett and soil borne infections are known to cause rapid spread of disease in sugarcane, bountiful of aerial infections resulted in rapid spread of the disease or aids in large-scale disease build-up, supplementing primary sources of infections. Summer showers, continuous humid weather during grand growth phase and waterlogging during maturity phase along with continuous monocropping of the popular cv Co 0238 in the command area were attributed to the large-scale disease outbreaks. Hence, disease management strategy has to be revised to tackle aerial spread of the disease.

MicroRNAs (miRNAs) play critical roles in development, and dysregulation of miRNA expression has been observed in human malignancies. Recent evidence suggests that the processing of several primary miRNA transcripts (pri-miRNAs) is blocked posttranscriptionally in embryonic stem cells, embryonal carcinoma cells, and primary tumors. Here we show that Lin28, a developmentally regulated RNA binding protein, selectively blocks the processing of pri-let-7 miRNAs in embryonic cells. Using in vitro and in vivo studies, we found that Lin28 is necessary and sufficient for blocking Microprocessor-mediated cleavage of pri-let-7 miRNAs. Our results identify Lin28 as a negative regulator of miRNA biogenesis and suggest that Lin28 may play a central role in blocking miRNA-mediated differentiation in stem cells and in certain cancers.

In India, red rot caused by Colletotrichum falcatum exhibits enormous variation in pathogenicity on sugarcane. The new cultivars released for commercial cultivation succumb to new pathotypes of the pathogen after some years in disease endemic regions. Due to the variability in C. falcatum , screening for red rot resistance in sugarcane progenies is being taken up with designated pathotype(s) separately for each agroclimatic regions in the country. The predominant C. falcatum pathotype of tropical India Cf671 (CF06) isolated from the then ruling cultivar CoC 671 is being used in tropical regions for disease screening. However, recently the pathotype has exhibited a reduced virulence on new cultivars and that has resulted in inconsistencies in disease reaction between artificial testing and field reaction under natural conditions. Hence, a detailed study was conducted during the past seven seasons on its pathogenicity on a set of 32 cultivars varying in red rot resistance in comparison with a new pathotype Cf94012 isolated from the cultivar Co 94012. The resistant cultivars such as BO 91, CoS 8436 and Co 98010 exhibited resistance reaction to both the pathotypes. However, other resistant cultivars such as Co 94008, Co 99006, Co 2001-15, Co 0238 and CoV 92102 showed a shift in their reaction to the new pathotype Cf94012 as moderately susceptible (MS) or susceptible (S) from resistant (R)/moderately resistant (MR) reactions in case of Cf671. Further, disease reaction on eight cultivars with MS behaviour and 11 susceptible cultivars clearly revealed a higher virulence of Cf94012 as compared to Cf671. Overall, the pathogenic behaviour of the two pathotypes during seven seasons revealed a higher virulence of Cf94012 as compared to Cf671 on resistant, moderately susceptible and susceptible cultivars. Although the pathotype Cf671 remained virulent on its host cultivar CoC 671, it could not exhibit such virulence on the cultivars developed in the recent years. Further, the study revealed that once a popular cultivar is removed from cultivation as in the case of CoC 671, the pathotype adapted to it no longer maintains its virulence, whereas the recently originated pathotype exhibits a higher virulence on the new cultivars of the host. This study also suggests adaptation of C. falcatum to the host cultivars.

Vegetative propagation in sugarcane favours accumulation of pathogens inside the canes and carryover of pathogenic inoculum through planting materials. Except foliar diseases, disease-infected setts serve as a primary source for disease spread for most of the diseases in the crop. In case of fungal diseases, planting infected setts leads to disease builds up in plant crop and probably death of the affected clump. However, in case of non-fungal diseases continuous accumulation of pathogens systemically leads to loss of vigour in sugarcane varieties referred to as ‘varietal degeneration’ and this results in loss of yield potential in elite commercial varieties. Past decades witnessed many such instances of degeneration in popular sugarcane varieties and their replacement with new varieties. With the development of precise molecular diagnostic tools, the associated pathogens were precisely identified. Under Indian conditions, it was found that combined or separate infections of viruses causing mosaic and yellow leaf (YL), phytoplasmas causing grassy shoot and leaf yellows and bacterium causing ratoon stunting disease are associated with varietal degeneration. The degeneration was rapid and severe when all these pathogens infect sugarcane together as compared to their separate infections. However, among all these diseases, YL contributes more towards degeneration of sugarcane varieties. The disease occurrence to epidemic levels in different states is a serious concern for sugar industry and due to that longevity of the affected varieties in the field is threatened. Meristem-tip culture combined with molecular diagnosis was found effective eliminate the pathogens efficiently from the cane. Developing disease-free nurseries is imperative to sustain productivity of sugarcane and to realize yield potential of popular sugarcane varieties in India.

Tuberous Sclerosis Complex (TSC) is caused by TSC1 or TSC2 mutations, resulting in hyperactivation of the mechanistic target of rapamycin complex 1 (mTORC1). Transcription factor EB (TFEB), a master regulator of lysosome biogenesis, is negatively regulated by mTORC1 through a RAG GTPase-dependent phosphorylation. Here we show that lysosomal biogenesis is increased in TSC-associated renal tumors, pulmonary lymphangioleiomyomatosis, kidneys from Tsc2 +/− mice, and TSC1/2 -deficient cells via a TFEB-dependent mechanism. Interestingly, in TSC1/2 -deficient cells, TFEB is hypo-phosphorylated at mTORC1-dependent sites, indicating that mTORC1 is unable to phosphorylate TFEB in the absence of the TSC1/2 complex. Importantly, overexpression of folliculin (FLCN), a GTPase activating protein for RAGC, increases TFEB phosphorylation at the mTORC1 sites in TSC2 -deficient cells. Overexpression of constitutively active RAGC is sufficient to relocalize TFEB to the cytoplasm. These findings establish the TSC proteins as critical regulators of lysosomal biogenesis via TFEB and RAGC and identify TFEB as a driver of the proliferation of TSC2 -deficient cells. Tuberous sclerosis complex (TSC) is a multiorgan disease that can lead to hyperactive mTORC1 due to deficient TSC1 or TSC2 protein function. Here, the authors find that despite high mTORC1 activity, TFEB localizes to the nucleus and drives lysosomal gene expression via a non-canonical Rag-dependent mechanism.

Yellow leaf disease (YLD) caused by Sugarcane yellow leaf virus (ScYLV), a Polerovirus, Luteoviridae occurs in major sugarcane growing countries across the world. During late 1990s it was recorded in India. Although the disease was initially thought to be a minor disease in the country, by 2005 onwards the disease severity attained epidemic status across the states. Currently, the ruling varieties such as Co 86032, Co 0238, CoV 09356 etc. in India are affected by disease epidemics, thereby cane productivity is reduced up to 50% and juice yield by 40–50% in severe cases. ScYLV and other sugarcane viruses causing mosaic and bacterium causing ratoon stunting disease, cause varietal degeneration in the field. Systemic accumulation of the viruses and the bacterium in high titre reduces vigour of the varieties in the subsequent vegetative generations or ratoons, hence their potential yield of the varieties could not be harnessed. Virus spreads to the field through infected setts and Melanaphis sacchari, sugarcane aphid is the insect vector which transmits the virus among the plants in the field. The virus was characterized on complete genome basis and about 10 genotypes were recognized across the countries. The genotype ScYLV-IND predominantly prevails in India. Various diagnostics, based on serological and molecular tools were developed for the virus, among them tissue blot and RT-PCR assays are commonly used. Among the disease management strategies, disease resistance and clean seed have the practical feasibility. Hence parental clones and pre-release varieties are screened for disease resistance in India. Virus elimination enabled through tissue (meristem) culture in combination with molecular diagnostics is the most efficient approach to contain the disease in the field and to address varietal degeneration in sugarcane. Such efforts led to varietal rejuvenation and increase in cane yield by 30–35% under field conditions in popular sugarcane varieties.

In this work, microwave-shielding behavior of epoxy thermosetting plastic reinforced with silanized Cu and Cu–Fe 3 O 4 compound particles were studied in frequency bands E, F, I, and J. The principal aim of this work is to evaluate the significant advantage of surface-modified magnetic and conductive fillers over as-received fillers in microwave shielding. The conductive and magnetic properties of epoxy resin were improved by additions of Cu and Fe 3 O 4 particles. Compound particles of Cu–Fe 3 O 4 were produced by mechanical alloying process (ball milling). The compound particles were surface treated by 3-Aminopropyltrimethoxysilane (APTMS) for better dispersion in epoxy resin matrix. Functional groups on particle’s surface after silane surface treatment were confirmed by FT-IR spectra analysis. The TEM images revealed that effective Cu–Fe 3 O 4 particle compounding was formed at 1 h milling time. The maximum dielectric constant of 6.8 and magnetization of 675E −6 were observed for surface-modified compound particle-reinforced epoxy composite designation RCF 2 . Similarly, maximum microwave attenuation of 35% (44 dB) was observed for surface-modified compound particle-reinforced composite designation RCF 2 in ‘J’-band frequency.

Accurate computational prediction of B-cell epitopes can greatly enhance biomedical research and rapidly advance efforts to develop therapeutics, monoclonal antibodies, vaccines, and immunodiagnostic reagents. Previous research efforts have primarily focused on the development of computational methods to predict linear epitopes rather than conformational epitopes; however, the latter is much more biologically predominant. Several conformational B-cell epitope prediction methods have recently been published, but their predictive performances are weak. Here, we present a review of the latest computational methods and assess their performances on a diverse test set of 29 non-redundant unbound antigen structures. Our results demonstrate that ISPIPab performs better than most methods and compares favorably with other recent antigen-specific methods. Finally, we suggest new strategies and opportunities to improve computational predictions of conformational B-cell epitopes.