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Seed ageing is an inevitable process that reduces seed quality during storage. When seeds deteriorate as a result of the lipid peroxidation process, it leads to produce toxic volatile organic compounds. These volatiles served as an indicator for the viability of stored seeds. With this background, the study was conducted to profile the volatile organic compounds emitted from rice seeds during storage. Volatile profiling of stored rice var. Co 51 seeds was done through Headspace-Solid phase microextraction/ Gas chromatography-mass spectrometry (HS-SPME/GCMS). The study clearly demonstrated that the significant decrease in physiological and biochemical quality attributes was noted due to an increase in the strength of volatiles released during ageing. When the release of total volatile strength reached more than 40%, a significant reduction in physiological attributes such as germination, root and shoot length, dry matter production and vigour index were observed. With respect to biochemical properties, a significant increase in electrical conductivity of seed leachate, lipid peroxidation and lipoxygenase activity, and decrease in dehydrogenase, catalase and peroxidase activities were observed. However, the highest reduction in all these properties were recorded when the total volatile strength reached to 54.90%. Finally, the study concluded that, among all the volatiles, 1-hexanol, 1-butanol, ethanol, hexanal, acetic acid, hexanoic acid and methyl ester were the most closely associated volatiles with seed deterioration. It indicates that these components could be considered the signature components for assessing the seed quality in rice during storage.

An experiment was conducted to profiling the volatile organic compounds emitted from groundnut seeds during storage and also to assess the volatiles emission level during seed deterioration. Volatile organic compounds profiling of stored groundnut seeds was done through GC-MS at monthly intervals. The results showed that several volatile compounds were released from stored groundnut seeds and all the compounds are falling into eight major groups viz., alcohols, aldehydes, acids, esters, alkanes, alkenes, ketones and ethers. The study clearly demonstrated the influence of volatile organic compounds emission level on physiological and biochemical properties during storage. There was a significant decrease in physiological and biochemical quality attributes noted due to an increase in the strength of volatiles released during ageing. When the release of total volatile strength reached more than 50%, a significant reduction in physiological attributes such as germination, root and shoot length, dry matter production and vigour index were observed. With respect to biochemical properties, a significant increase in electrical conductivity of seed leachate, lipid peroxidation and lipoxygenase activity, and a decrease in dehydrogenase, catalase and peroxidase activities were observed. However, the highest reduction in all these properties was recorded when the total volatile strength reached 92.72%. The study concluded that the volatiles released during seed deterioration could be considered the signature components for detecting the seed quality during storage.

Blackgram (Vigna mungo L.) is one of the major pulse crops grown throughout India. Prediction of seed vigour and field emergence of seed before sowing is important for assured yield. A standard germination test is time-consuming and does not always show the seed lot potential performance, especially if field conditions are not optimal. There is need of advanced technology, which can give a precise result in a short period. The experiment was conducted to correlate the radicle emergence test with seed vigour parameters to predict seed vigour and planting value of 10 varying vigour lots (L1, L2, L3, L4 - high vigour lots; L5, L6, L7 - medium vigour lots; L8, L9, L10 - low vigour lots) of blackgram var. VBN 6. The study showed that all the seed vigour parameters of the blackgram were more highly correlated with the percentage of radicle emergence with 2 mm length than with 1 mm length. The correlation analysis results showed that the radicle emergence test with 2 mm radicle length at 28 hours had a highly significant negative correlation with EC (electrical conductivity) of seed leachate (-0.974**), followed by MJGT (mean just germination time) (-0.967**) and MGT (mean germination time) (-0.933**). However, it was positively correlated with field emergence (0.972**), germination (0.952**) and dehydrogenase enzyme activity (0.928**). The maximum R2 value of 0.923 was recorded in the 28-hour counting of radicle emergence with a length of 2 mm compared with the 26-hour counting of radicle emergence with a length of 1 mm (0.913). The study concluded that counting 2 mm radicle emergence at the 28th hour could be used to quickly evaluate seed vigour in field emergence in blackgram seed lots.

Aquaporins (AQPs) are water channel proteins. They play a key role in maintaining water balance and homeostasis in cells under stress conditions in living organisms. AQPs are pore forming transmembrane proteins that facilitate water movement and various small neutral solutes across cellular membranes. Aquaporin expression and transport functions are modulated by various phytohormones mediated signalling in plants. Transcriptome analysis revealed the role of aquaporins in regulating hydraulic conductance in plant roots and leaves. Different AQPs found in the seed system have individual functions that are more time and tissue specific, ultimately helping in the seed imbibition process to complete seed germination. Seed specific TIP3s aquaporin helps to maintain seed longevity under expressional control of ABI3 during seed maturation and heat shock proteins and late embryogenic abundant proteins. Under stress circumstances, the major significance of aquaporin expression in seeds is to maintain water influx and efflux rates, as well as protein modification, post translational alterations, nutritional acquisition and allocation, subcellular trafficking and CO2 transport. The present review mainly focused on aquaporin structure, classification, role and functional activity during solute transport, reproductive organs development, plant growth development, abiotic stress response and also various roles in seeds such as seed biology, seed development and maturation, seed dormancy, seed germination and longevity.

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.