@tnau.ac.in
Associate Professor (Soil Science & Agrl. Chemistry)
TAMIL NADU AGRICULTURAL UNIVERSITY
• Behaviour of pesticides in soil environment
• Plant Chemistry and nutrition - Nitrogen and phosphorus nutrition to crops
• Organic sources of fertilization for crops
• Chemistry of sodic soils and its management
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Yerra Pavani, Ponnusamy Janaki, Ramasamy Jagadeeswaran, Arjunan Sankari, Alaguthevar Ramalakshmi, and Palanisamy Murali Arthanari
Horizon E-Publishing Group
The interaction between fertilizer nutrients and pesticides and their impact on tomato production and quality has been insufficiently studied in tropical agricultural conditions. This research investigated four fertilizer nutrient management (FNM) approaches: major nutrients (NPK), micronutrients, farmyard manure (FYM) and traditional farmer practices (FP), alongside three herbicides—glyphosate, pendimethalin and metribuzin applied using seven methods. Results highlighted the substantial influence of FNM strategies and herbicide applications on tomato growth and yield parameters such as plant height, cluster count, fruits per plant, fruit number and yield per plant. Notably, the NPK+FYM strategy consistently yielded superior results across herbicides and application methods. Individually applied herbicides, particularly glyphosate, exhibited detrimental effects on growth and yield parameters, and the negative impact was conspicuously higher with glyphosate > metribuzin > pendimethalin than with their sequential or combined application. While herbicides decreased tomato yield across FNM practices, the reduction ranged from 1.90–10.95%, 1.79–6.75%, 1.62–6.49% and 1.40–9.10% in NPK, NPK+MN, NPK+FYM and FP treatments, respectively. Fruit quality remained unaffected by FNM practices and herbicides, except for elevated ascorbic acid content and shelf life under NPK+FYM. Herbicide residues in tomato fruits were within permissible limits (below 0.1 mg/kg for glyphosate and 0.05 mg/kg for pendimethalin and metribuzin) across treatments. This study showed that the NPK+FYM practice is the best strategy for increasing the tomato yield and quality parameters besides reducing the herbicide’s toxicity effect on tomato growth at an early stage.
Dhandayuthapani Udhaya Nandhini, Ponnusamy Janaki, Subramanian Venkatesan, Kandasamy Senthilraja, Eagan Somasundaram, and Sadasivam Meena
Springer Science and Business Media LLC
P. Shanmugapriya, S. Rathika, T. Ramesh, and P. Janaki
Agricultural Research Communication Center
Background: Finger millet production and productivity is lowering in India due to the growth of different weed species. Weeds are the prime yield limiting biotic constraints in finger millet. Therefore, the present investigation has been carried out to find out the suitable weed management practices on the performance of finger millet. Methods: In this regard, a field experiment was carried out during Kharif, 2018 at Anbil Dharmalingam Agricultural College and Research Institute, Tiruchirapalli, Tamil Nadu, India to evaluate the different weed management practices for transplanted finger millet under sodic soil. The experiment comprised of ten weed management practices with different herbicidal treatments viz., pre emergence (PE) application of pendimethalin at 750 g/ha, oxyfluorfen at 50 g/ha, bensulfuron methyl at 60 g/ha + pretilachlor at 600 g/ha, early post emergence (EPOE) application of bispyribac sodium at 25 g/ha, PE pendimethalin at 750 g/ha fb EPOE bispyribac sodium at 25 g/ha, PE oxyfluorfen at 50 g/ha fb EPOE bispyribac sodium at 25 g/ha, PE bensulfuron methyl at 60 g/ha + pretilachlor at 600 g/ha fb EPOE bispyribac sodium at 25 g/ha, PE oxyfluorfen at 50 g/ha fb hand weeding (HW) at 30 DAT, HW at 15 and 30 DAT and unweeded control (UWC) in transplanted finger millet. Result: The results revealed that lower nutrient removal by weeds, higher nutrient uptake by crop and yield parameters viz., productive tillers/m2, earhead weight and total grains/earhead were registered in application of PE bensulfuron methyl at 60 g/ha + pretilachlor at 600 g/ha fb EPOE bispyribac sodium at 25 g/ha. The highest grain and straw yields were also registered in application of PE bensulfuron methyl at 60 g/ha + pretilachlor at 600 g/ha fb EPOE bispyribac sodium at 25 g/ha and it was on par with hand weeding at 15 and 30 DAT.
D. Udhaya Nandhini, P. Janaki, and E. Somasundaram
Springer Science and Business Media LLC
M. Dhanalakshmi, S. Meena, P. Janaki, S. Karthikeyan, and L. Nalina
Diva Enterprises Private Limited
T. Thilagavathi, P. Janaki, and R. Mugesh Kumar
ANSF Publications
This study is essential for assessing the binding capacity of Prosopis wood biochar to commonly used herbicides, Pretilachlor and Pendimethalin. Understanding their sorption dynamics at varying biochar application rates and exposure times is crucial for sustainable and effective herbicide management in intensively farming agricultural fields and for reducing environmental contamination. The Prosopis wood biochar was produced in an earthen kiln at 300-350°C. The batch experiment was conducted to study the sorption potential of biochar additions at rates of 0, 5, and 10 t ha-1. The herbicides were added to the homogenized soil-biochar mixes at zero, whole, twice, and four times the recommended dose. The sorption of the herbicides by soil biochar mixture was studied for 12 and 24 hours. The result showed that Pendimethalin sorption increased with biochar application rate, requiring 24 hours for 95% sorption at 4X dose without biochar (77.95 mg/kg soil) and 12 hours with 10 t/ha biochar (75.82 mg/kg soil). The Kd value increased with biochar application (0.57-77.95 mg/kg soil) and decreased with pendimethalin application (77.95-3.04 mg/kg soil). Maximum sorption (95%) was attained within 12 hours for 1X and 2X rates and 24 hours for 4X rates when biochar was added. This demonstrated that although pendimethalin residue in the soil can be immobilized by adding biochar within 8 hours at lower rates, more than 24 hours were required when pendimethalin was applied at higher rates or repeatedly. Biochar can be used to reduce pendimethalin leaching in agricultural fields, especially sodic soils, at higher application rates.
A. Sangothari, S. Radhamani, P. Janaki, V. Ravichandran, M. Gnanachitra, and N. Thavaprakaash
Agricultural Research Communication Center
Background: In rice belts, cultivation of rice under aerobic conditions provides an alternative way to reduce the enormous amounts of water usage, by using 50 percent of the water when compared to traditional cultivation. However, micronutrient deficiencies are more common in aerobic rice during its early stages of growth. Mycorrhizal fungi were found to be efficient in mobilizing the nutrients under aerobic situations. Methods: The field experiment was conducted in Department of Agronomy, Tamil Nadu Agricultural University, Coimbatore. The experiment consisted of thirteen treatments which includes different recommended doses of VAM 50, 62.5 and 75kg ha-1 along with different combinations of foliar application of 0.5% urea, 0.5% ZnSO4 and 1% FeSO4. Result: The study revealed that combined application of 150 % of recommended dose of VAM and foliar application of 0.5% urea + 0.5% ZnSO4 + 1% FeSO4 at 25 and 45 DAS significantly increased the VAM colonization area, photosynthetic pigments and growth parameters such as plant height, shoot and root weight, root growth, leaf area index and yield attributes and it was found to be a better optionin rice cultivation to overcome the micronutrient deficiencies in its earlier stages under aerobic conditions.
Pavani Yerra, Ponnusamy Janaki, Alaguthevar Ramalakshmi, Ramasamy Jagadeeswaran, Arjunan Sankari, and Palanisamy Murali Arthanari
Czech Academy of Agricultural Sciences
Dhandayuthapani Udhaya Nandhini, Subramanian Venkatesan, Kandasamy Senthilraja, Ponnusamy Janaki, Balasubramaniam Prabha, Sadasivam Sangamithra, Sivaprakasam Jidhu Vaishnavi, Sadasivam Meena, Natarajan Balakrishnan, Muthurajan Raveendran,et al.
Frontiers Media SA
Traditional rice is gaining popularity worldwide due to its high nutritional and pharmaceutical value, as well as its high resistance to abiotic and biotic stresses. This has attracted significant attention from breeders, nutritionists, and plant protection scientists in recent years. Hence, it is critical to investigate the grain metabolome to reveal germination and nutritional importance. This research aimed to explore non-targeted metabolites of five traditional rice varieties, viz., Chinnar, Chithiraikar, Karunguruvai, Kichili samba, and Thooyamalli, for their nutritional and therapeutic properties. Approximately 149 metabolites were identified using the National Institute of Standards and Technology (NIST) library and Human Metabolome Database (HMDB) and were grouped into 34 chemical classes. Major classes include fatty acids (31.1–56.3%), steroids and their derivatives (1.80–22.4%), dihydrofurans (8.98–11.6%), prenol lipids (0.66–4.44%), organooxygen compounds (0.12–6.45%), benzene and substituted derivatives (0.53–3.73%), glycerolipids (0.36–2.28%), and hydroxy acids and derivatives (0.03–2.70%). Significant variations in metabolite composition among the rice varieties were also observed through the combination of univariate and multivariate statistical analyses. Principal component analysis (PCA) reduced the dimensionality of 149 metabolites into five principle components (PCs), which explained 96% of the total variance. Two clusters were revealed by hierarchical cluster analysis, indicating the distinctiveness of the traditional varieties. Additionally, a partial least squares-discriminant analysis (PLS-DA) found 17 variables important in the projection (VIP) scores of metabolites. The findings of this study reveal the biochemical intricate and distinctive metabolomes of the traditional therapeutic rice varieties. This will serve as the foundation for future research on developing new rice varieties with traditional rice grain metabolisms to increase grain quality and production with various nutritional and therapeutic benefits.
Libi Robin, P, Kaleeswari, R.K., Janaki, P, Uma. D, Karthikeyan, and S
ANSF Publications
This study on soil carbon dynamics provides valuable insights for sustainable agricultural practices, optimizing crop productivity and environmental sustainability in maize-based cropping systems. The present study aimed to find out the soil characteristics and carbon dynamics in maize-based cropping systems in the Western zone of Tamil Nadu, India. Soil samples from six cropping systems were analyzed for bulk density, sand, silt, clay content, pH, available nutrients (N, P, K, Zn), total organic carbon (TOC), oxidizable organic carbon fractions, microbial biomass carbon (MBC), and carbon pools. The distribution of oxidizable organic carbon fractions varied among cropping systems and soil depths. The easily decomposable and moderately labile fractions were highest in the maize-black gram system, while the recalcitrant fraction showed variations across cropping systems. The active carbon pool (Cf1 + Cf2) was highest at 2.53 g kg-1 in the maize-blackgram system, while the passive carbon pool (Cf3 + Cf4) was also highest at 3.79 g kg-1 in this system. The study also assessed the carbon stock and microbial biomass carbon. TOC content decreased with depth, with the highest values observed in the topsoil. The maize-black gram system had the highest TOC content at all depths. MBC content followed a similar pattern, with the highest values in the topsoil and the maize-black gram system. These findings provided insights into the soil characteristics and carbon dynamics in maize-based cropping systems in the study area. The long-term integration of maize cultivation with blackgram demonstrated significant enhancements in organic carbon levels, TOC content, microbial biomass carbon (MBC), and both passive and active carbon pools characterized by rapid turnover rates.
S Venkatesan, P Masilamani, T Eevera, P Janaki, S Sundareswaran, and P Rajkumar
Forest Research Institute Malaysia
Libi Robin. P, Kaleeswari. R.K., Janaki. P, Uma. D, and Karthikeyan. S
ANSF Publications
Soil carbon mineralization is vital for carbon sequestration but affected by factors like soil type and residue quality. Understanding the process and factors is still incomplete, including the interplay between soil properties and organic residues and the need for accurate kinetic models. Research faces significant challenges in describing carbon mineralization dynamics. The present study aimed to investigate carbon mineralization in three soils located in Tamil Nadu, India (S1, S2 and S3) that possess distinct textures. The study also focused on the effects of five different plant residues (Rice, maize, sugarcane, cotton and turmeric) on carbon mineralization in these soils. Incubation experiments were conducted for 150 days, and CO2 evolution was measured at different time intervals of 7, 10, 15, 30, 60, 90, 120 and 150 days. The performance of three kinetic models (Zero order model, exponential kinetic model and first order model) was also evaluated in predicting carbon mineralization using experimental data. The results showed that the rate and extent of carbon mineralization varied significantly among the different soils and residues. The highest carbon mineralization was observed in rice (989.02 µg C/g/day) and maize (966.53 µg C/g/day) residue, while the lowest was in sugarcane (752.09 µg C/g/day) residue. Among the kinetic models, the first-order kinetic model provided the best fit for all treatments (R2=0.98). The findings suggest that soil texture and residue quality play crucial roles in carbon mineralization. The first order kinetic model can be useful for predicting carbon mineralization in different soil-residue systems. These results have implications for managing soil carbon sequestration and mitigating climate change.
M. DHANALAKSHMI, S. MEENA, P. JANAKI, S. KARTHIKEYAN, and L. NALINA
Gaurav Publications
Phosphorus (P) use efficiency is very low (5 to 25%) due to fixation with Ca+2/Mg+2 in alkaline/calcareous soils and Fe2+/Al3+ in acid soils, reduces the availability of phosphorus in soil. Among the various approaches used to enhance PUE, polymer coated fertilizers are relatively a new concept. Therefore, to alleviate the effects of low use efficiency of inorganic fertilizers and its losses in soil, the incubation study was conducted during 2020 at Tamil Nadu Agricultural University to check the slow-release behaviour of coated DAP fertilizer using biopolymers like chitosan and sodium alginate. The incubation experiment was made with six different coatings of biopolymers and uncoated DAP for studying the release behaviour of P from coated fertilizers. Randomized block design was followed with seven treatments in triplicate and sampling was taken at the intervals of 2nd hour, 4th hour, 120th hour, 7, 14, 28, 35, 42 and 49 days of incubation. A study on slow-release property of coated fertilizers indicated that the treatment combination of both chitosan and sodium alginate (C5A5 - CSACDAP) coated DAP performed well by releasing the P from coated fertilizer was achieved till 35th day of incubation followed by the combination of both chitosan and sodium alginate (C4A4 - CSACDAP). This study indicated that the combination of both the polymers forms a strong polyion complex and tends to give the P release for a longer period than the individual coatings of both polymers on the DAP granule.
VR. MAGESHEN, P. SANTHY, S. MEENA, MR. LATHA, A. SENTHIL, T. SARASWATHI, and P. JANAKI
Gaurav Publications
When iodine levels in the soil are inadequate, resulting in limited crop uptake and as a result, a population with insufficient iodine intake. Iodine deficiency can be avoided by biofortifying commonly consumed crops with iodine. Tomato is the best crop for biofortification study as it is having the capacity to store excess iodine in pholoem. The field experiment was carried out in Thondamuthur block of Viraliyur village at Coimbatore district of Tamil Nadu in 2021. The purpose of this study was to determine the effect of biofortication of iodine in residual tomato growth, yield, quality and iodine content. Potassium iodate and Chitosan were applied in the form of soil, foliar and Chitosan iodate complex at different stages of plant growth. The results revealed that the soil fertilization of potassium iodate alone resulted in lower uptake of residual iodine in fruits because the iodine was susceptible to high volatilization and less phyto-availability. While foliar spray alone increased the residual iodine content in roots and stem. However, residual higher iodine accumulation in the tomato fruits was achieved through the combination of foliar and iodine Chitosan forms. As electrostatic interaction between Chitosan and iodate prevents volatilization and gradually increases the bioavailability of iodine from soil to fruits. Based on the discussion, biofortification of iodine through potassium iodate Chitosan complex paved the way for the improvement of growth, yield, quality and iodine content in fruits. Hence, biofortification of iodine through iodate Chitosan complex increased the iodine content in tomato fruit and introducing it in our daily diet may be helpful to reduce iodine deficiency disorder.
R. Mohanapriya, R. Kalpana, A. Alagesan, K. R. Latha, A. Senthil, and P. Janaki
ANSF Publications
In India, about 3.77 million ha of the country's geographical area is affected by sodicity. There is an urgent need to minimize further land degradation and restore the fertility of degraded soils to meet the growing demand for food. The most effective way to overcome salt stress is by applying nutrients through soil and foliar. In this context, a field experiment was conducted at Anbil Dharmalingam Agricultural College and Research Institute (ADAC & RI), Tiruchirappalli, in the summer of 2022 to study the reclamation potential of soil amendments and foliar nutrition in sodic soil. The experiment was laid out in a split-plot design with three replications. The treatment comprised of soil amendments viz., M1- Pongamia green leaf manure (GLM) @ 6.25 t ha-1, M2- Pressmud @ 10 t ha-1, M3-CSR GROMOR @ 25 kg ha-1, M4-Gypsum @ 50 % GR, M5-Gypsum @ 50 % gypsum requirement (GR) + Pongamia GLM @ 6.25 t ha-1, M6-Gypsum @ 50 % GR + Pressmud @ 10 t ha-1, M7-Gypsum @ 50 % GR + CSR GROMOR @ 25 kg ha-1 and M8- Farmers practice, in main plots and foliar nutrition viz., S1- Foliar spray (FS) of CSR GROMOR @ 3% @ 30 DAS, S2-FS of Brassinosteroid (BRs) 0.2 ppm @ 30 DAS and S3-FS of Melatonin 60 ppm @ 30 DAS in sub plots. The results showed that gypsum @ 50 % GR + Pressmud @ 10 t ha-1+ FS of Brassinosteroid 0.2 ppm @ 30 DAS(M6S2) registered significantly (P=0.05%) lowest pH (8.07), ESP (11.62%), exchangeable Na+ (2.93 c mol (p+) kg-1) with higher exchangeable Ca2+(11.23 c mol (p+) kg-1), Mg2+ (8.09 c mol (p+) kg-1) and K+(0.82 c mol (p+) kg-1). It also increased soil available nutrients (235.6, 24.57 & 309.6 kg NPK ha-1) and grain yield (1110 kg ha-1) of green gram. However, it was on par with gypsum @ 50 % GR + CSR GROMOR @ 25 kg ha-1 + FS of Brassinosteroid 0.2 ppm @ 30 DAS(M7S2). Hence it was concluded that the application of gypsum along with pressmud or CSR GROMOR combined with FS of brassinostroid had a remarkable effect in reducing soil sodicity and increasing the productivity of green gram.
VR. Mageshen, P. Santhy, S. Meena, M. R. Latha, A. Senthil, T. Saraswathi, and P. Janaki
ANSF Publications
An iodine biofortification experiment was conducted by applying potassium iodate fertilizer in soil and foliar form and chitosan complex forms to investigate the growth, yield, quality and uptake of iodine in shivam hybrid of tomato in Palaviduthi soil series of Coimbatore region. Soil fertilization alone resulted in lower uptake of iodine in fruits because the iodine is susceptible to high volatilization and less phytoavailability and also resulted in less yield and poor quality of fruits. When the chitosan and potassium iodate were applied in combination through foliar form, the quality of the fruits was found to be superior (carotene-1.24 mg 100gm-1 ascorbic acid- 3.56 mg 100gm-1, titrable acidity-0.96%), with higher fruit yield (94.81 t ha-1) and uptake of iodine in fruits (0.99ppm). Potassium iodate alone, either in the form of soil or foliar application, increased the quality of fruits, but it did not prevent the loss of various pigments and acids during ripening and also the loss of iodine through volatilization. But chitosan conserved the losses by reducing the respiration rate and oxygen permeability. Further, chitosan formed an electrostatic interaction with potassium iodate, preventing volatilisation and gradually increasing the bioavailability of iodine from soil to fruits. Hence biofortifying iodine in the form of potassium iodate chitosan complex was preferred for enhancing yield, improving quality and increasing the iodine content in fruits.
P. Shanmugapriya, S. Rathika, T. Ramesh, and P. Janaki
Journal of Applied and Natural Science ANSF Publications
Weeds are the major biotic constraints in finger millet production and account for 41 to 63% yield loss. Weed management through herbicides plays a major role in increasing productivity. The field experiment was conducted at Anbil Dharmalingam Agricultural College and Research Institute, Tamil Nadu Agricultural University, Tiruchirapalli during Kharif, 2018, to evaluate the weed management practices on the growth and yield of transplanted finger millet under sodic soil conditions. The experiment was laid out in Randomized Block Design (RBD) with ten treatments and three replications. The treatment comprised weed management practices with different herbicides and their combinations. The results revealed that the highest plant height, total number of tillers/m2, dry matter production, leaf area index and crop growth rate were registered in PE application of bensulfuron methyl at 60 g/ha + pretilachlor at 600 g/ha fb EPOE application of bispyribac sodium at 25 g/ha. The highest grain and straw yield was also registered in PE application of bensulfuron methyl at 60 g/ha + pretilachlor at 600 g/ha fb EPOE application of bispyribac sodium at 25 g/ha, and it was on par with hand weeding at 15 and 30 DAT. Hence, in transplanted finger millet under sodic soil, the application of PE bensulfuron methyl at 60 g ha-1 + pretilachlor at 600 g ha-1 fb EPOE bispyribac sodium at 25 g ha-1 was found to be the most viable option for effective weed control besides increased productivity and profitability.
S. Venkatesan, P. Masilamani, T. Eevera, Ponnusamy Janaki, Sendrayaperumal Sundareswaran and P. Rajkumar
Poor seed germination is a major issue in teak (Tectona grandis) propagation. Teak seed dormancy is thought to be the reason for delayed germination. So far, specific dormancy mechanisms have not yet been identified. In order to study the influence of presowing treatments on germination, seedling vigour, and biochemical attributes of fresh teak drupes collected from the seed production area of Top Slip in Tamil Nadu. The collected drupes were subjected to different presowing treatments viz., T1 - control, T2 - soaking and drying for 6 days, T3 – T18 (soaking and drying for 5 days + soaking in different concentrations of thiourea, potassium nitrate, hydrogen peroxide and calcium oxychloride for 12 hours). Treated drupes were placed for germination in earthen pots and kept in open sunlight. In parallel, true seeds extracted from untreated drupes were also subjected to germination under in vitro conditions as a check. A higher percentage of germination (40%) was recorded in true seeds under in vitro conditions when compared to the treated and untreated drupes under in vivo conditions. Among the treated drupes sown under in vivo conditions, the drupes given soaking + drying for 5 days + soaking in 2% calcium oxychloride (CaOCl2) recorded higher germination (17.16) with better seedling vigour. Analysis of teak true seeds and mesocarp extract in high-performance liquid chromatography showed that gibberellic acid was found only in true seeds, whereas the other compounds, viz., indole-3-acetic acid, indole butyric acid, abscisic acid and coumarin, were not present in the true seed or mesocarp.
P. Janaki, A. Alagesan, J. Ejilane, S. Nithila, P. Balasubramaniam, and P. Santhy
ANSF Publications
The prominent issue faced by the farmers of Cauvery Delta regionin Tamil Nadu particularly Tiruchirapalli District is the lack of timely release of water for rice nursery preparation and transplanting. Hence wet seeding of rice is recommended for timely cultivation. On the other hand, sodic nature of the soil warrants rice cultivation only. Therefore, the present investigation was carried out to study the different soil and crop management practices on alleviating sodicity stress and improving rice (variety ADT 3) productivity under water-scarce conditions. The experiment was laid in a split plot design with six mainplots,including rice wet seeding, daincha (Sesbania aculeata) application as green manure, anti-oxidant microbial consortia (AOMC) spray and four sub-plots with graded levels of NPK based on soil test values with three replication. Results showed that the daincha incorporation @ 6.25 t/ha followed by rice wet seeding + AOMC spray @1.5 % with 125 % soil test based NPK had significantly increased thechlorophyll content, SPAD values, proline content and grain and straw yields which remained on par with daincha incorporation @ 6.25 t/ha followed by rice wet seeding + AOMC spray @1.5 % with 100 % soil test based NPK.Significantly lower ESP at 5% level and higher phosphatase activity in soil was also recorded by daincha incorporation @ 6.25 t/ha followed by rice wet seeding + AOMC spray @1.5 % with 125 % and 100 % soil test based NPK. Gross return, net return and B:C ratio were also higher in the plot, which received daincha incorporation @6.25 t/ha followed by rice wet seeding + AOMC spray @1.5 % with 100 % soil test based NPK. The present study reveals that the inclusion of ectophytic microbial population spray in rice plants and the management practices helps the crop to tolerate the sodicity stress under water-scarce condition by maintaining required physiological functions like proline synthesis and enzyme activities etc which need to be further explored at the genotypic level.
B. Asan Mohamed and P. Janaki
ANSF Publications
Pesticides have become a basic necessity for yield development. This might be credited to the quickly expanding population, which has presented weight on the food creation industry.Fourier Transform Infra-red Spectroscopy utilizes sample with less course of action, less time consuming, simple, fast, non-destructive and environmental friendly infrared-based method. It makes use of Smart iTR window and pellets use on omnic transmission window. In FTIR the peaks formed for the representative sample are from 800 cm-1 to 4000 cm-1 of wavenumbers against the % transmittance. The FTIR spectra obtained for pesticide formulations were on par with the NIST (National Institute of Standards and Technology) spectra library. Comparing the commercial-grade spectra with the Spectrabase, NIST library and Bio-rad software showed the peak ranges for different functional groups of the compound and can be examined with KnowItAll software’s ProcessItIR and AnalyseItIR. We can obtain the active principle of the peak, peak intensities. This method can be viewed as genuine choices to long and tedious chromatographic strategies as a rule suggested for quality control of commercially accessible pesticide formulations and check for adultered formulations that harm agricultural produce.
P.M. Brindhavani, , P. Janaki, G. Gomadhi, T. Ramesh, J. Ejilane, , , , and
Triveni Enterprises
Aim: To elucidate the influence of non target Arbuscular Mycorrhizal (AM) fungi on glyphosate dissipation in okra cultivated sodic soil of Tamil Nadu. Methodology: A field experiment was carried out during Rabi 2017-18 to study the interactive effect of glyphosate and Arbuscular mycorrhizal fungi (AM) on glyphosate dissipation in sodic soil from okra (A. esculentus) grown field. Experiment was laid adopting Randomized Block Design (RBD) with different rates of glyphosate and with and without AM fungi. Glyphosate was applied as pre-plant herbicide 20 days before sowing, and AM biofertilizer was applied as basal before sowing of okra. Soil samples were collected from the field at different time interval after glyphosate application and analysed for glyphosate and Amino Methyl Phosphonic Acid (AMPA) residues. Results: Glyphosate persistence decreased with time and degraded with the mean half-life ranging from 5.09 to 10.35 days by following first order reaction kinetics. AMPA was witnessed from day 1 and increased up to 15th day and followed first order reaction kinetics dissipation with the mean half-life of 8.62 to 13.06 days. Glyphosate and AMPA residues were recorded below detection limit (0.01 mg kg-1) on 45th and 60th days, respectively, in soil. Interpretation: The higher rates of glyphosate showed enhanced persistence of glyphosate and its metabolite AMPA in soil, hence application of AM fungi 100 kg ha-1 with lower glyphosate rate of 6 ml/L can be recommended for okra cultivated sodic soil with the safer waiting period of after 45 days harvest.
RagaPriya A, Janaki P, and Arulmozhiselvan K
Journal of Applied and Natural Science ANSF Publications
Repeated and long term application of same herbicides forms bound residues in soil and becomes point source of pollution over a period of time and harms the soil microorganisms. Among the different herbicides, the atrazine and pendimethalin is widely and repeatedly used molecule in maize and sunflower cultivation for weed control, respectively. Hence the present study was undertaken to investigate the bound residue of the applied herbicides in soil under long term fertilized condition with varied nutrient sources since 1909 in North-Western agro-climatic zone of Tamil Nadu under the semi-arid tropic region of India. Soil samples were collected at the time of maize and sunflower harvest and analysed for the bound fraction of atrazine and pendimethalin compounds respectively. The results showed that the repeated application of these herbicides at recommended dose formed a considerable amount of non-extractable bound residues in soil. While the bound fraction of parent atrazine was found below detectable limit, pendimethalin was at a quantifiable level in the soil irrespective of fertilization sources. However the bound form of atrazine metabolites, namely Des ethyl Deisopropyl atrazine (DEDIA) and Hydroxy atrazine (HA) was extracted from the maize cultivated soil. Bound forms of HA (4.34%) and DEDIA (3.43%) and pendimethalin (3.14%)to the applied quantity were witnessed at a higher amount in control plot than the fertilized plots. The omission of any one major nutrient recorded elevated DEDIA bound form than the HA fraction. The non-extractable bound residues of both the herbicides were detected at different proportions according to the herbicide nature, sources of fertilization and the crops cultivated in the soil. The fraction of bound form of atrazine metabolites was detected at higher level than the pendimethalin in soil. The present study revealed that the bound residues of atrazine, its metabolites and pendimethalin can be mineralized into the soil solution and bio-augmented over a period of time under the conditions of repeated application. Hence the remobilization of bound residues of these herbicides must be considered while gauging the environmental hazard and effect on non-target organisms.
S. Venkatesan, P. Masilamani, P. Janaki, T. Eevera, S. Sundareswaran, and P. Rajkumar
Journal of Applied and Natural Science ANSF Publications
Nitric oxide (NO) is an important signalling molecule employed by plants to control many physiological aspects. This review summarizes that crosstalk between NO/H2O2/Ca2+ signalling pathways that drive pollen tube for sexual reproduction in flowering plants. NO is produced in seeds by both enzymatic and non-enzymatic sources that control many physiological aspects of seeds. The interplay of NO and Reactive oxygen species are likely important players in hormonal crosstalk controlling seed germination and dormancy. Mechanism of seed germination and dormancy is mainly regulated by plant hormones like Abscisic acid (ABA) and Gibberellic acid (GA). Based on mode of action of NO with reference to triggering the germination of crop seeds under abiotic stress condition it is infer that there is a linkage between NO and plant growth regulator production. NO cross-talk with reactive oxygen species (ROS) during abiotic stress condition, modulate the light and hormone depended developmental process in the early stage of plant development. NO action to enhancing abiotic stress tolerance by improving antioxidant enzymes and protection against oxidative damage in many crops are discussed in detail.
M. Prasannakumari, M. Akilan, S. Kalaiselvan, A. Subramanian, P. Janaki and P. Jeyaprakash
EJPB, ISPB, CPBG - Tamil Nadu Agricultural University
In any crop breeding program, the effective selection of traits that are associated with yield depends on the information on nature and magnitude of variation in the traits and its response to the environment. A study was conducted to determine the variability, heritability, correlation and path analysis of yield and yield components in BC1F2 generation of backcross combination, CO 51 × RPHP 48. The population was developed in order to introgress the high iron content in CO 51 background. The narrow difference between GCV and PCV indicates that there was a meagre influence of environment on the expression of 12 traits studied. Broad sense heritability was high for grain iron content and low for kernel length/breadth ratio. Grain yield was found to be significant and positively correlated with the number of productive tillers per plant, panicle weight, the number of grains per panicle and 100 seed weight indicating yield improvement can be achieved through improvement of these traits. The results of genotypic path analysis revealed that the number of productive tillers per plant and kernel length had a high positive direct effect which could be considered as good selection criteria for yield improvement.