Effect of presowing seed treatments on teak (Tectona grandis L. F) drupes dormancy and germination

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

Role of nitric oxide in seed biology and seed production: A review

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

In-situ Transesterification of Jatropha curcas L. Seeds for Biodiesel Production using Supercritical Methanol

In-situ supercritical methanol transesterification for production of biodiesel from Jatropha curcas L. (JCL) seeds was successfully being carried out via batch-wise reactor system, under varying temperatures of 180 - 300 °C, pressures of 6 - 18 MPa, reaction time of 5 - 35 min and seeds-to-methanol ratio of 1:15 - 1:45 (w/v). In this study, the extracted oil obtained showed the presence of FAME referring as biodiesel, indicating that transesterification reaction had occurred during the extraction process. The results showed that the biodiesel yield was obtained at optimum conditions of 280 °C, 12 MPa, 30 min and 1:40 (w/v) were 97.9%

Exploring the Storage Potential of Groundnut Var.TMV (Gn) 13 under Modified Atmospheric Storage Conditions

The aim of the study is to identify the suitable modified atmospheric storage condition required for long term storage of groundnut (Arachis hypogaea L.) variety TMV (Gn) 13. The experiment was conducted during 2022 at Department of Seed Science and Technology, Tamil Nadu Agricultural University, Coimbatore.  The groundnut pods and kernels were subjected into different storage conditions viz., pods stored in gunny bag, kernels stored in gunny bag, kernels stored in polythene bag, kernels stored with N₂gas and kernels stored in vacuum conditions.  The results revealed that pod storage recorded the maximum germination percentage (73%), root length (14.5cm), shoot length(14.3cm), dry matter production (3.47 g 10 seedlings -1) and vigour (2136). Similarly, enzymes viz., dehydrogenase( 0.72 OD value), peroxidise (1.29U mgˉ¹ protein minˉ¹), alpha amylase (13.60mg maltose min-1) and catalase activity (1.253 µmolH₂O₂ minˉ¹gˉ¹ protein) were also maximum in pod storage with minimum harmful effect of pest(0.6%) and fungus incidence(17%). The nitrogen storage conditions also have maximum enzyme activity viz., dehydrogenase (0.64 OD value), peroxidise (1.24U mgˉ¹ protein minˉ¹), alpha amylase (13.58 mg maltose min-1) and catalase activity (1.220 µmolH₂O₂ minˉ¹gˉ¹ protein) with minimum harmful effect of pest (0.6%) and fungus incidence (20%). Present study, it is concluded that groundnut kernels stored under modified atmospheric storage i.e. nitrogen gas storage can maintain the seed longevity by minimizing the deterioration process in groundnut equally as that of pod storage. Further, it will helps to minimize the expenditure towards transport and storage

Poly(o-anisidine)–anion composite films as sensing platform for biological molecules

Polyanisidine films doped with two different anions, viz., perchlorate and paratoluene sulphonate anions are prepared electrochemically on a gold substrate. Polyanisidine films doped with the anions aid in retaining the redox conductivity of the polyanisidine films. This behaviour is similar to that of polyaniline films. Unlike polyaniline films, even smaller ions like perchlorate and paratoluene sulphonate are sufficient for retaining the redox conductivity of the film, which may be primarily due to the compact, non-permeant films formed during electropolymerization. The films are found to be suitable for the immobilization of glucose oxidase enzyme and are found to be an efficient sensing matrix for glucose. The films also exhibited catalytic activity towards the oxidation of NADH. These studies indicate the usefulness of polyanisidine–anion films as sensing platform for biomolecules

Traditional Cultivars Influence on Physical and Engineering Properties of Rice from the Cauvery Deltaic Region of Tamil Nadu

Standard unit operations/equipment have not evolved for the traditional rice varieties of the Cauvery Deltaic region of Tamil Nadu. The fame of traditional rice is increasing nowadays owing to its health benefits. Non-standard unit operations may cause rice grains to crack during milling, accumulating more broken rice and yields in products of inferior quality. As a result, research into the physical properties of rice is crucial for the development of rice processing equipment that minimizes post-harvest losses during milling. Hence, an assessment was made to evaluate 30 traditional rice cultivars on their Physical (grain length, width, thickness, shape, and size), gravimetric (bulk, true, tapped density, porosity, Carr’s index, and Hausner ratio), and engineering characteristics (equivalent, arithmetic, square mean, and geometric mean diameter) using standard protocols, with the goal of reviving and preserving older varieties. The results from the analysis showed significant variations (p 2, respectively. Of the 30 varieties, 28 were under the high amylose category, and 2 belonged to the intermediate type. The Pearson correlation was established to study the interrelationships between the dimensions and engineering properties. Principal component analysis (PCA) reduced the dimensionality of 540 data into five principal components (PC), which explained 95.7% of the total variance. These findings suggest that it is possible to revive old landraces through careful selection and analysis of these properties. The superior characteristics of these traditional varieties can be further evaluated for breeding programs in order to improve the cultivation of these cherished rice landraces to enhance nutritional security