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Pigeonpea is the second most important pulse crop after chickpea in India. The yield of pigeonpea is very low due to indeterminate growth habit and poor source-sink relationship. Plant growth regulators are known to influence the source-sink relationship and stimulate the translocation of photo-assimilates thereby helping in effective flower formation, fruit and seed development and ultimately enhance productivity of the crops. With this background, a field experiment was conducted with pigeonpea (CO Rg 7) under irrigated condition in Tamil Nadu Agricultural University, Coimbatore. An experiment was aimed at determining the effect of various nutrients and growth-promoting hormones on the growth parameters and yield of pigeonpea (Cajanus cajan (L.) Millsp.). The Factorial Randomised Block Design was used in the field trial and was replicated three times. At the vegetative stage, the treatments included foliar sprays of growth inhibitors such as M2-Mepiquat chloride (MC) @ 500 pp, M3-Chlormequat chloride (CC) @ 500 ppm and M1- Control. At flower initiation and 15 days later, various plant growth regulators, such as T2-SA (100 ppm), T3-BR (0.1 ppm), T4-Napthyl acetic acid (40 ppm), T5-Nutrients (ZnSO4 @ 0.5 percent + H3BO3 @ 0.3 percent, T6-Mono Ammonium Phosphate @ 2 percent, and T7-TNAU Pulse Wonder @ 1 percent), T8-Nutrient consortia I (1%) and T9-Nutrient consortia II (1%), were used. Among the treatments, the combination of Chlormequat chloride and nutrient consortia treatments (M3T8&M3T9) had better performances in growth parameters and yield of pigeonpea (CO Rg 7). Foliar application of M3T8-Chlormequat chloride and Nutrient consortia I (1%) resulted significantly (P

Background: This experiment was done to analyze the colchiploids obtained in two bajra napier hybrid genotypes named CO6 and TNCN 1534. Stomatal size is considered as one of the main parameters in analysing the variants developed by colchicine application. Methods: Two methods were adopted for inducing polyploidy BN hybrids. In case of whole immersion method, budded setts were completely immersed in concentrations of 0.05%, 0.10%, 0.15%, 0.20% and 0.25% for 3 and 6 hours duration. In case of the cotton swab method, the nodded setts were covered with a thin layer of cotton and same five concentrations were given continuously for a period of over two days. After transplanting them in the field for 30 days, evaluation of stomatal length and width was done. Result: The stomatal measurements changed with various range of concentrations and the method of application. In the case of whole immersion method, 0.20% and 0.25% concentration for 3 and 6 hours produced variants having largest width and length of stomata and also covered the largest range for mean values. In cotton swab treatment, highest range for stomatal measurements were seen at 0.20% and 0.25% concentrations. The whole immersion method was able to generate a wide range for stomatal length and width as compared to cotton swab method. Hence, it can be deciphered that whole immersion method was more effective than cotton swab method in this study. The highest concentration of 0.25% was the most effective in inducing changes in the treated plants in both the methods. Through this, we were able to identify some putative colchiploids in the study. These screened polyploids were forwarded for further analysis which were then used to identify genotypes having desirable forage and quality parameters.

The soil test value is based on the soil test-based fertilizer prescription/ recommendation equation. Each crop harvesting after the next crop is necessary to analyze the soil. Therefore, it is necessary to develop an alternative technique to predict postharvest soil tests after the harvest of every crop. For that a study was conducted in mixed black calcareous soils at Tamil Nadu agricultural University, Coimbatore to develop the post-harvest prediction equations for available nitrogen, phosphorus and potassium in barnyard millet cropping sequence based on a multiple regression model by considering post-harvest soil test value as the dependent variable and initial available nutrients, fertilizer doses and crop yield or crop nutrient uptake as an independent variables. The developed model was validated by computing R2 value, RMSE (root means square error), RE (relative error), and the ratio of performance to deviation (RPD) and the developed model was found to be valid. Using the validated model, post-harvest soil test values were predicted. A fertilizer recommendation was made for blackgram based on predicted post-harvest soil test values in the barnyard millet-blackgram cropping sequence. The predicted soil test values were compared with actual soil test values and it revealed that the developed model is fairly accurate and best-fitted with more precision. The predicted post-harvest soil test values of barnyard millet could be used in order to prescribe fertilizer for desired yield targets for subsequent crops.

Background: Weeds smother the finger millet due to crop’s slow growth during the initial stages which reduces the yield substantially by 5-70%. Intensive use of herbicides is gaining popularity among the farmers now a days due to its effectiveness in controlling weeds, timeliness and reduced cost. Methods: The current field experiment was conducted at Tamil Nadu Agricultural university during kharif season, 2021 under irrigated condition with twelve herbicide treatments laid out in Randomized Complete Block Design (RCBD) with three replications. Result: Pre-emergence application of pyrazosulfuron ethyl 15 g ha-1 significantly reduced the total weed density and total weed dry weight at 90 days after transplanting over all the other herbicides used. This treatment also considerably improved the plant parameters such as plant height, total number of tillers, plant dry matter production, Grain and stover yield and yield parameters such as productive tillers, ear head weight of transplanted finger millet which was statistically followed by the application of pendimethalin 750 g ha-1 as pre-emergent spray. Similar trend was followed in case of net returns and B: C ratio. while lower plant parameters were observed with the application of tembotrione 12 g ha-1.

Globally, drought stress causes the negative impact on agriculture production. However, microbial inoculation is the suitable cost-effective technology to attenuate the drought stress. The aim of this experiment was conducted to evaluate the impact of microbial inoculation on morpho-physiological characters of sorghum under moisture stress condition. A pot experiment with sorghum was conducted to access the role of previously identified bacterial endophyte strains. For comparison, two non-inoculated control treatments (T1: absolute control and T2: drought control) were maintained to compare the drought and inoculation effect. Drought was imposed at flowering stage and soil moisture was measure at frequent days. When the soil moisture attains close to zero, plants were rehydrated. During drought and rehydration period, plant morphological and physiological characters were evaluated. Drought stress drastically reduces the plant characters in control (T2-uninoculated) plant. Whereas, in the presence of bacterial inoculation considerably reduces the drought effect also Bacillus sp. inoculation treatment promoted better recovery during their rehydration process than absolute control. Overall, Bacillus sp. inoculation was the most promising bacterium for possible field trials.

Ozone stress identification in crops through remote sensing is a promising technology that has a major role in predicting stress-related physiological response. The spectral reflectance approach to phenotyping of rice cultivars is a non-destructive and accurate method to assess ozone stress. In this study, the leaf spectral reflectance of 15 rice cultivars was explored to evaluate the photosynthetic capacity under elevated ozone stress. Ozone injury percentage (OIP), a common indicator to identify ozone stress of rice leaves combined with leaf spectral signatures was used to identify the best fit spectral indices. The normalized difference spectral index (NDSI) was used to determine significant wavebands that showed the best correlation with leaf ozone injury. The correlation coefficient (r) between NDSI and OIP were ranged from -0.79 to 1. Normalized difference spectral index, NDSI[R564,R568], and NDSI[R558,R573] were identified as the best Pearson's correlation with leaf ozone injury percentage with correlation coefficient more than 0.96. The evaluated NDSI in visible regions were identified as a sensitive region to ozone injury. Additionally, results were compared with previously established indices and also evaluated for correlation with plant physiological traits. The correlation coefficient of determination (R2) > 0.5 was observed for newly developed spectral indices, NDSI[R564,R568] and NDSI[R558,R573] with physiological traits compared to previously established 20 indices. The highest R2 of 0.674 were observed for the spectral index, NDSI[R558,R573] with photosynthetic rate and R2 of 0.673 for NDSI[R564,R568] with relative chlorophyll content. As a result, the current research has implications for the selection of the best capable spectral regions for early detection of ozone stress in rice cultivars without destructing the crop. The outcome of the present work suggests that newly developed spectral indices could assist in remote sensing technology in monitoring large scale ozone stress and crop modeling studies to ensure food security.

The compound 1-O-methyl chrysophanol (OMC) which belongs to a class of hydroxyanthraquinones was isolated from Amycolatopsis thermoflava strain SFMA-103 and studied for their anti-diabetic properti...

Catalyst-free one-pot CN and CC bond formation is described as a simple and ecofriendly method for the synthesis of pyrazole-aniline linked coumarin derivatives. Employing this protocol, a series of derivatives were synthesized in good to excellent yields and tested against different bacterial strains as well as fungal strains. Most of the compounds exhibited potential antimicrobial activity against both Gram-positive and Gram-negative bacterial strains. Among them, the compounds 4b, 4e, 4 h, 4i and 4 k exhibited promising activity on all the tested bacterial strains with values ranging between 1.9 and 7.8 µg/mL. In addition, these compounds were tested against various fungal strains and were found to exhibit potential antifungal activity. Fascinatingly, among the tested derivatives, the compounds 4e, 4 h and 4i were found to be equipotent to miconazole (positive control) against some of the tested fungal strains. Moreover, these compounds showed promising bactericidal, Candida-cidal and biofilm inhibition activities. Further, mechanistic study was carried out with the most active derivative 4i indicated that these compounds inhibit the ergosterol biosynthesis pathway. Keywords: 4-Hydroxycoumarin, Pyrazole, Catalyst-free, Antimicrobial, Ergosterol, Biofilm

Actinobacteria are prolific producers of a large number of natural products with diverse biological activities. In the present study, an actinobacterium isolated from sunflower rhizosphere soil sample collected from Medak, Andhra Pradesh, South India was identified as Amycolatopsis thermoflava strain SFMA-103. A pigmented secondary metabolite in culture broth was extracted by using methanol and it was further purified by silica gel column chromatography with methanol-chloroform solvent system. Structural elucidation studies based on UV-visible, 1D and 2D-NMR, FT-IR, and mass spectroscopic analyses confirmed the structure as 1-methoxy-3-methyl-8-hydroxy-anthraquinone. It showed significant in vitro anticancer activity against lung cancer and lymphoblastic leukemia cells with IC50 values of 10.3 and 16.98 μM, respectively. In addition, 1-methoxy-3-methyl-8-hydroxy-anthraquinone showed good free radical scavenging activity by DPPH method with an EC50 of 18.2 μg/ml. It also showed other promising superoxide radical scavenging, nitric oxide radical scavenging and inhibition of lipid peroxidation activities. This is a first report of antiproliferative and antioxidant activities of 1-methoxy-3-methyl-8-hydroxy-anthraquinone isolated from A. thermoflava strain SFMA-103 which may find potential application in biotechnological and pharmaceutical fields.

A simple, green, efficient and three-component procedure has been developed for the synthesis of 4′-phenyl-1′ H -spiro[indoline-3,2′-quinazolin]-2-ones ( 4a – m and 6a – g ) and 2,4-diphenyl-1,2-dihydroquinazolines ( 8a – l ) by the reaction of 2-aminobenzophenones, isatins or aromatic benzaldehydes and ammonium acetate in excellent yields under catalyst-free conditions using ethanol as a solvent. This method provides several advantages such as operational simplicity, higher yields, shorter reaction time and catalyst-free conditions with ethanol as a solvent makes the method eco-friendly as well as economical. All the 4′-phenyl-1′ H -spiro[indoline-3,2′-quinazolin]-2-ones were tested for antimicrobial activity against both Gram-positive and Gram-negative bacterial strains including a fungal strain Candida albicans MTCC 3017. Among these, the compounds 4f , 6a , 6c and 6g showed appreciable antibacterial activity with MIC values 7.8 μg/ml selectively against Gram-positive bacteria, Micrococcus luteus MTCC 2470. On the other hand, compounds 4j , 4m , 6c and 6g showed good activity with MIC values ranging between 3.9 and 7.8 μg/ml against Gram-negative bacteria, Klebsiella planticola MTCC 530.

A simple, green, efficient and three-component procedure has been developed for the synthesis of 4′-phenyl-1′ H -spiro[indoline-3,2′-quinazolin]-2-ones ( 4a – m and 6a – g ) and 2,4-diphenyl-1,2-dihydroquinazolines ( 8a – l ) by the reaction of 2-aminobenzophenones, isatins or aromatic benzaldehydes and ammonium acetate in excellent yields under catalyst-free conditions using ethanol as a solvent. This method provides several advantages such as operational simplicity, higher yields, shorter reaction time and catalyst-free conditions with ethanol as a solvent makes the method eco-friendly as well as economical. All the 4′-phenyl-1′ H -spiro[indoline-3,2′-quinazolin]-2-ones were tested for antimicrobial activity against both Gram-positive and Gram-negative bacterial strains including a fungal strain Candida albicans MTCC 3017. Among these, the compounds 4f , 6a , 6c and 6g showed appreciable antibacterial activity with MIC values 7.8 μg/ml selectively against Gram-positive bacteria, Micrococcus luteus MTCC 2470. On the other hand, compounds 4j , 4m , 6c and 6g showed good activity with MIC values ranging between 3.9 and 7.8 μg/ml against Gram-negative bacteria, Klebsiella planticola MTCC 530.

The physiochemical and biological properties of microbial derived gold nanoparticles have potential applications in various biomedical domains as well as in cancer therapy. We have fabricated anti-proliferative bacterial mediated gold nanoparticles (b-Au NPs) using a culture supernatant of Streptomyces clavuligerus and later characterized them by UV-visible, TEM, DLS, XRD and FT-IR spectroscopic techniques. The capping agent responsible for the nanoparticle formation was characterized based on SDS-PAGE and MALDI-TOF-MS analyses. They were tested for anticancer activity in A549, HeLa and DU145 cell lines. The biocompatibility and non-toxic nature of the nanoparticles were tested on normal human lung cell line (MRC-5). The b-Au NPs induced the cell cycle arrest in G2/M phase and also inhibited the microtubule assembly in DU145 cells. Mechanistic studies, such as ROS, MMP, Cyt-c, GSH, caspases 9, 8 and 3 activation and the Annexin V-FITC staining, along with the above parameters tested provided sufficient evidence that the b-Au NPs induced apoptosis through the intrinsic pathway. The results supported the use of b-Au NPs for future therapeutic application in cancer therapy and other biomedical applications.

Soil test based fertilizer prescription equations (FPEs) were developed for desired yield target of transgenic cotton under Integrated Plant Nutrition System (IPNS) through drip fertigation on Vertic Ustropept of Tamil Nadu, south India. To validate the equations, an experiment was conducted on the same soil series. The results revealed that the deviation recorded in the achievement of target aimed, was within the range of ±10% (90–110%) proving the validity of the FPEs. STCR treatments greatly influenced the growth and yield attributes of the crop and recorded significantly higher yield, response ratio (RR) and benefit-cost ratio (BCR) than blanket, farmer's practice and control. STCR-IPNS treatments performed better than STCR-NPK alone treatments. There was build-up of post-harvest soil fertility in the STCR treatments. The treatment, STCR-IPNS for 4.0 t/ha of cotton proved its superiority over all other treatments in terms of yield, uptake, response ratio, BCR and quality parameters. This treatment recorded an yield increase of 62.4 and 65.6%, respectively, over blanket and farmer's practice. Therefore, it could be concluded that these FPEs could be made use of for prescribing soil test based fertilizer doses for transgenic cotton on Inceptisols under drip fertigation.