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Mycosphaerella musicola, M. fijiensis and M. eumusae are known to cause banana yellow Sigatoka, black Sigatoka and Eumusae leaf spot diseases respectively. However, differentiating the causative species has been challenging and the responses of banana landraces to this pathogen were little known. Purposive sampling surveys were conducted in different agro-climatic zones of Kerala state, India, to collect the leaf samples with Sigatoka leaf spot-like symptoms, to document the symptom expression on different landraces and to confirm the identity of the pathogen at species level. Fields surveyed during the post-monsoon period had 100% disease incidence with highest per cent disease severity of 43.90% in nine-month old cv. Palayankodan, while lowest PDS of 3.33% was observed in three-month old cv. Njalipoovan, during a pre-monsoon survey. Initial symptoms were small brown streaks, later developing into oval or elliptical brown spots with greyish centre and subsequently coalescing for leaf necrosis. Symptoms in different landraces varied across the zones. Sequencing and analysis of the ITS region from 50 isolates collected during the survey showed 99–100% homology with M. eumusae. Phylogenetic analyses further proved the species identity of the local isolates. Comparing the ITS barcodes of the three species of Mycosphaerella along with the local isolates confirmed that the pathogen inciting Sigatoka leaf spot in Kerala state, India, is Mycosphaerella eumusae.

The fungal diseases in banana cause major yield losses for millions of farmers around the globe. Early detection of these diseases helps the farmers to devise successful management strategies. The characteristic leaf blade discoloration pattern at the earlier stages of infection could be used to understand the onset of each disease. This paper demonstrates a methodology for classification of three important foliar diseases in banana, using local texture features. The disease affected regions are identified using image enhancement and color segmentation. Segmented images are converted to transform domain using three image transforms (DWT, DTCWT and Ranklet transform). Feature vector is extracted from transform domain images using LBP and its variants (ELBP, MeanELBP and MedianELBP). These texture based features are applied to five popular image classifiers and comparative performance analysis is done using ten-fold cross validation procedure. Experimental results showed best classification performance for ELBP features extracted from DTCWT domain (accuracy 95.4%, precision 93.2%, sensitivity 93.0%, Fscore 93.0% and specificity 96.4%). Compared with traditional methods of feature extraction, this novel method of fusing DTCWT with ELBP features has attained high degree of accuracy in precisely detecting and classifying fungal diseases in banana at an early stage.

Sugarcane (Saccharum spp hybrids) is a major commercial crop grown in tropical and subtropical regions in different countries. Like any other crop, biotic stresses are a major constraint to sugarcane production and of these fungal and viral diseases are causing economically significant losses, worldwide. Among various viral diseases causing major destruction, leaf fleck caused by Sugarcane bacilliform virus (SCBV) is one of the emerging threats which affects global exchange of sugarcane germplasm. In sugarcane varietal development, parents of interest are crossed and true seed or “fluff” is obtained to develop new varieties. SCBV occurs in the new varieties throughout India and such widespread occurrence was suspected due to true seed transmission of SCBV. However, until now, no experimental evidence has corroborated these observations. In this study, we have attempted to establish possible transmission of the virus from sugarcane parents to their progenies. Eight- and three-month-old progenies from 18 crosses and their parents were tested through PCR assays to confirm presence of the virus. All the tested parents were found to be positive to the virus infection. About 50 to 100% of the progenies were positive to SCBV in PCR assays. Real-time PCR assays of three-month-old progenies along with their parents also revealed that all the samples were positive to the virus. Fluff samples of the parents Co 0238 and Co 11015 commonly used in hybridization were also tested positive for the virus. Even though viral titre is comparatively low in the fluff samples, it could be concluded that true seed acquires the virus from the parents and it has a direct role in disease transmission. Probable seed transmission may be attributed to the rampant occurrence of leaf fleck under field conditions in the country.

Wastewater containing heavy metal ions is considered as the serious environmental problem in human society. Adsorption as the widely used method plays an important role in wastewater treatment, which is based on the physical interaction between metal ions and sorbents. Drumsticks are reported to have efficient adsorbing property. It has been found that Moringa causes alteration in testosterone levels, preventing testicular damage and hence is capable of protecting against the toxic effect of hazardous material. Based on this phenomenon of adsorption by Moringa species, we are trying to remove heavy metals from aqueous sample. The bio sorption of heavy metals by non-living biomass of plant origin is an innovative and alternative technology for the removal of the pollutants from aqueous solution and offers several advantages such as low-cost bio sorbents, high efficiency, minimization of chemical and/or biological sludge, and regeneration of the bio sorbent. Moringa oleifera (drumsticks) has a number of advantages including low cost, biodegradable sludge production and lower sludge volume, and also it does not affect the pH of the water. Apart from turbidity removal, Moringa oleifera seeds also possess antimicrobial properties. Amount of adsorption is considerably larger when activated charcoal is used. Thus, this work reports preparation of activated charcoal from drumsticks seeds and fibres. These are generally part of kitchen waste; thus, its preparation and utilisation for heavy metal toxicity not only controls water pollution but also help in reduction of kitchen waste. It will serve as an effective, cheap and robust and green tool for toxicity control. The paper reports the removal of heavy metal (Pb, Ni, Cd, As in this study) by application of prepared activated charcoal tablets via MATLAB assisted paper based sensors. These tablets will surely serve as point-of- care devices for removal of heavy metal toxicity.

Quantitative structure–activity relationship (QSAR), Density functional theory and molecular docking studies have been performed on a series of 49 1-[2-Hydroxyethoxy) methyl]-6-(phenylthio)-thymine (HEPT) derivatives as anti-HIV agents. A genetic algorithm multiple linear regression (GA-MLR) analysis has revealed that the five variable model comprises of 2D autocorrelation, 2D atom pairs and constitutional descriptors of these compounds are the governing factors for their biological activity. Using this GA-MLR model some new compounds have been proposed that have higher potency than the existing ones. The molecular docking study has shown that these new compounds can form hydrogen bonds with the receptor and have effective steric interactions.

Banana bract mosaic disease caused by Banana bract mosaic potyvirus (BBrMV) is reported to instigate heavy loss in banana and plantain across Asia. Almost all the cultivars of banana succumb to the disease resulting in malformed bunches weighing less than half of normal ones. In the current study the coat protein (CP) gene segment present at the 3’ terminal region of the viral genome amplified by RT-PCR was cloned into expression vectors, pRSET-C and pGEX-4T-2 to use it for raising polyclonal antiserum which in turn will aid in developing assays to detect the virus. Recombinant BBrMV CP (rCP) in pRSET-C when expressed was insoluble whereas, it was in the soluble fraction when expressed from pGEX-4T-2. The GST-fusion protein was purified by GSH sepharose affinity column chromatography and western blot analysis was performed using anti GST antibodies. 360 µg/ml of protein was purified from 1 l of culture. The GST tag was cleaved from the purified protein by incubation with thrombin at 25°C overnight. The rCP was characterized using ultracentrifugation, fluorescence spectroscopy and electron microscopy. The tagless monomer failed to assemble to virus like particles (VLPs) in vitro which was substantiated by fluorescence spectroscopy. This study will be first step towards deciphering structure and functions of Banana bract mosaic virus coat protein.

Fusarium wilt disease caused by Fusarium oxysporum f. sp. cubense (Foc) is one of the most important diseases that affects the banana production which leads to huge economic loss. Thus, to avoid yield loss and manage the disease on time, morphological and cultural characterization of the pathogen is essential as a preliminary identification step. Thirty isolates were collected from different banana growing regions of Kerala. The isolates were grown on half strength PDA medium. The isolates showed extreme variations in their cultural and morphological characters. Most of the isolates produced white coloured aerial mycelium and few of them were greyish white with white to pink pigmentation. Colony diameter ranged from 59.6 to 90.0 mm at seven days after incubation at 25ºC. The mycelial growth rate varied from 0.83 cm/day to 2.40 cm/day. Length and breadth of macroconidia ranged from 15.01 to 20.20 μm and 2.14 to 5.07 μm whereas, it ranged from 4.49 to 7.42 μm and 1.35 to 3.13 μm for microconidia. The diameter of chlamydospores varied from 5.68 to 9.58 μm. Whereas, the inter septal length and breadth of hyphae varied from 16.14 μm to 22.94 μm and 4.22 μm to 6.57 μm. The cluster analysis based on the quantitative parameters classified the isolates based on variety and genome of the host plants. All the isolates from Rasthali/Poovan (AAB) and Njalipoovan (AB) belonged to the cluster A1 whereas the isolates from Kadali and Chenkadali varieties of banana formed the cluster A2. While, the clustering based on qualitative parameters was irrespective of the variety or genome of the host plant.

The efficacy of bioagents/organic preparations viz., cow dung extract + Pseudomonas fluorescens (1%), PGPR mix II (2%), P. fluorescens (2%), turmeric powder + baking soda mixture (5:1 per litre of water), salicylic acid (25ppm), KAU micronutrient multimix (Sampoorna) (1%), petroleum based mineral oil (0.1%) along with chemical check Bordeaux mixture (1%) and control were tested for the management of Eumusae leaf spot disease of French plantain cultivar Nendran ( Musa AAB). A field experiment was laid in the hotspot area of this disease at Banana Research Station, Kannara, Kerala during May 2016-2017 in Randomized Block Design (RBD) with nine treatments replicated thrice with nine plants per replication. The observations like Per cent Disease Severity (PDS), Youngest Leaf Spotted (YLS), Disease Development Time (DDT), vegetative and yield parameters were recorded. The results of the field experiments revealed that all the bioagents/organic preparations were equally effective in suppressing the disease when compared to the chemical check (Bordeaux mixture, 1%). Among the bioagents/organic preparations evaluated, the lowest per cent disease severity (PDS) of 20.93 per cent was recorded in plants sprayed with PGPR mix II (2%). While the maximum Disease Development Time (DDT) of 43 days and the highest (6.69) youngest leaf spotted were recorded in plants treated with turmeric powder + baking soda mixture (5:1) and Pseudomonas fluorescens (2%) respectively. The yield in terms of bunch weight was recorded highest (8.47 kg) in plants applied with P. fluorescens (2%) which was closely followed by PGPR mix II having a bunch weight of (7.93 kg). The study revealed that foliar spraying of PGPR mix II (20g/l) and P. fluorescens (20g/l) four times starting from the initial appearance of the disease on the lowest leaves of 75 per cent plants was safe and effective for the management of Eumusae leaf spot disease of banana

Freshly harvested seeds of chilli variety Anugraha were treated with halogens namely Calcium oxy chloride (CaOCl2) and Iodine crystal (I2) indirectly through a carrier Calcium carbonate (CaCO3). The treatments included Control (Untreated), CaOCl2 + CaCO3 (2g each/kg seed), CaOCl2 + CaCO3 (4g each/kg seed), Iodine crystal + CaCO3 (50mg each/kg seed) and Iodine crystal + CaCO3 (100mg each/kg seed). Seed treatment with CaOCl2 + CaCO3 @2g each/kg seed registered significantly higher values for fruits per plant, fruit weight, seed yield per plant and hundred seed weight followed by CaOCl2 + CaCO3 @4g each/kg seed. The treatments, CaOCl2 + CaCO3 @2 g each/kg seed and Iodine crystal + CaCO3 @100mg each/kg seed performed superior in seed quality with higher seedling vigour and lower electrical conductivity of seed leachates over other treatments, while untreated control recorded least seedling vigour indices and highest electrical conductivity.

Background: Management of bacterial wilt of tomato in Ralstonia solanacearum affected soils is a major issue in tomato cultivation in different agro-ecological regions in Kerala state which affects the production and productivity of the crop. To develop a suitable management protocol for this disease, the field experiments were conducted during 2019 and 2020 in a bacterial wilt-sick field at Kerala agricultural university, Thrissur, Kerala, India. Methods: Twelve different treatments viz. soil application of bleaching powder, soil test based lime application, streptocycline root dip, drenching of copper hydroxide and copper oxychloride at different doses, seed treatment and seedling dip with Pseudomonas fluorescens, drenching of Pseudomonas fluorescens, planting grafted seedlings and different integrations and combinations of the above treatments were assessed for the management of bacterial wilt. Result: The majority of integrations were superior over individual treatments. The higher yield with less disease incidence was obtained from the integration of soil treatment of bleaching powder (15 kg/ha) + soil test based lime application + streptocycline (@ 2 g/10 L) root dip + drenching of copper oxychloride (@ 0.3%) and therefore, this integration protocol is recommended for management of bacterial wilt of tomato in wilt affected soils in Kerala state.

An experiment was conducted to study the effect of seed invigoration with inorganic nanoparticles on plant growth and seed yield of chilli. Seed invigoration with nano particles of ZnO and TiO2 was found to be beneficial in improving yield and yield attributes. Seed treatment with nano ZnO @ 1300 mg kg-1 of seed and nano TiO2 @ 900 mg kg-1 exhibited increased plant height, fruits per plant, fruit length, fruit yield, number of seeds per fruit and seed yield.

Among fruit crops, banana is a significant fruit in agricultural production and trade. However, global banana production is severely affected by diseases, leading to substantial declination in the yield. Hence, timely detection and control of these diseases is necessary. Diagnosis of diseases by manual inspection of initial symptoms is quite challenging for farmers. This paper demonstrates a novel machine learning approach towards classification of three major foliar fungal diseases, Sigatoka, Deightoneilla and Cordana, using discoloration patterns appearing on the leaf blade. The images, after pre-processing and segmentation, are transformed to frequency domain using discrete orthonormal Stockwell transform (DOST). Feature vectors based on local neighborhood patterns such as local binary pattern (LBP), elliptic LBP (ELBP) and its variants, are extracted from DOST transformed images and classified using five prominent image classifiers. A comparative analysis of performance metrics through a ten-fold cross validation procedure is done. Classification accuracy of 95.9% is obtained for ELBP features when classified with artificial neural network classifier (ANN). The technique of integrating DOST with LBP based features has achieved significant accuracy compared to contemporary methods of disease classification in plants.

Fungicides are commonly used to manage plant pathogens. However, little is known about their effects on the non-target fungal communities that inhabit inside and outside the plant. These fungicides may have adverse effects on beneficial microbial communities with possible consequences for plant health and productivity. Hence, a metagenomic approach, based on the ITS2 region of fungal rDNA, was used to study the impact of foliar application of two fungicides (propineb and iprodione + carbendazim) on non-target tomato leaf fungal communities, in the context of early blight disease management. Metagenomic analysis revealed that the richness and diversity of tomato leaf fungal populations were adversely affected by the chemical treatments tested. Among the two fungicides, propineb (contact fungicide) imparted less non-targeted microorganisms than iprodione + carbendazim (systemic fungicide). In addition, all samples showed association of pathogenic genera Cladosporium, Corynespora, Pseudocercospora along with early blight pathogen Alternaria on tomato leaves that otherwise were undetected. Metagenomic studies also revealed a new mode of action for fungicides and bioagents besides their direct effect that is shifting the microbial community structure so that it provides greater resistance against the pathogen.

Background: The Janus enzyme family is regulated by various cytokines together with interleukins, interferons, and hormones like glycoprotein, thromboprotein, and hormone. Metamorphosis and translocations in the Janus Kinase genes leading to constitutively active Janus Kinase proteins are associated with a variety of hematopoietic malignancies, comprising the myeloproliferative disorders, acute lymphoblastic leukemia, acute myeloid leukemia (JAK2, JAK1), acute megakaryoblastic leukemia (JAK2, JAK3). Hence the study of the inhibitors of Janus Kinase is desired. Methods: Research and online content related to 1-amino-5H-pyrido [4,3-b]indol-4-carboxamide analogues (I) that were synthesized and evaluated for their JAK2 inhibitory activity is reviewed, and in order to design and develop still better and more effective JAK inhibitors, we have made Quantitative Structure Activity Relationship (QSAR), docking and ADMET studies on these compounds Results: The best GA-MLR equation based on four descriptors along with statistical parameters is obtained using QSARINS software. Using the model expressed by this study we predicted some new compounds of high JAK2 inhibition potency. Each predicted compound has very high potency with which only a few compounds of existing series can match. Conclusion: The QSAR and molecular modelling studies suggested that still better compounds can be designed if the flexibility of the molecules can be increased for which attempts can be made to have more saturated atoms in the molecules. Such a compound predicted by us was found to have interactions with the enzyme JAK2 almost in the same manner as the FDA approved compound, Momelotinib.