Decline In Vigor Research Articles

Drought alters the physiological quality of runner-type peanut seeds during seed formation

Sub-optimal water supply during crop development, especially during peak flowering and pod filling, affects the quality of the produced seeds, generally resulting in poor seed quality. The goals of this study were to identify the acquisition pattern of physiological components in peanut seeds as well as to assess the impact of drought during peanut seed development on its physiological quality. The research was conducted at the USDA-ARS National Peanut Research Laboratory in Dawson, GA for three consecutive years (2019, 2020, and 2021) using field conditions under two water regimes, well-watered control and drought stress. Rainout shelters were used to prevent rain in the drought-stressed block for 30 d, starting 80 d after planting. The well-watered block received supplemental irrigation when soil water potential reached -40 kPa. Peanut pods from the cultivar Georgia-06G were harvested at 2500 growing degree days, and the peanut maturity profile board was used to classify the pods into different maturity classes. Germination, vigor, desiccation tolerance (DT), and longevity tests were performed on seeds from each maturity class and both water regimes. The acquisition pattern for the physiological components of seed quality was developed for seeds grown under well-watered and drought conditions. Maximum germination occurred in ‘brown 1’ and ‘brown 2’ under drought and well-watered conditions, respectively. Both water regimes reached maximum vigor in the 'brown 1'; however, under well-watered conditions, vigor had a rapid decline after ‘brown 1’ while under drought stress, the decline in vigor was slower. Maximum DT was achieved between ‘orange’ and ‘brown 1’ under drought conditions, whereas under well-watered conditions, maximum DT was achieved between ‘brown 2’ and ‘black 1’. Seeds from immature classes had lower capacity to be stored compared with mature seeds. Overall, drought stress promoted greater physiological quality in the peanut seeds than the well-watered treatment. Maximum physiological quality was achieved in the transition from ‘orange’ into ‘brown 1' under drought conditions, and in the transition from ‘brown 2’ to ‘black 1’ class under well-watered conditions. Also, drought stress preserved seed quality for a longer period.

Comparative metabolomic analyses reveal metabolites associated with seed deterioration in Chinese cabbage

Seed deterioration during storage results in a decline in vigor, which has a negative impact on agricultural production. However, the mechanisms responsible for ageing are still poorly understood. The aim of present study was to investigate the physiological, biochemical, and metabonomic changes in naturally aged Chinese cabbage (Brassica pekinensis L.) seeds, and identify potential markers of seed deterioration. In this study, Chinese cabbage seeds with different moisture contents (1 % and 4 %) were stored under ambient conditions for 13 years. We employed a biochemical and metabolomics approach to investigate the impact of seed deterioration on naturally aged Chinese cabbage seeds and to identify the types and variations of differentially accumulated metabolites. Our findings demonstrate that the initial storage moisture content has a significant impact on the loss of seed vigor. The seed lot with an initial moisture content of 1 % exhibited higher viability and vigor after natural storage. High-vigor seeds showed higher catalase (CAT) activity, lower H2O2 and malondialdehyde (MDA) content, and reduced electrolyte leakage. No significant difference was observed between the two seed lots in terms of superoxide dismutase (SOD) activity, peroxidase (POD) activity, and soluble protein content. Metabolite analysis revealed 1,117 differential metabolites between the two seed lots. The differential metabolites were associated with various aspects of seed ageing, including changes in glycerophospholipids, phytohormones, antibiotics, reduction of antioxidant substances and raffinose, degradation of triglycerides, accumulation of toxic compounds, and DNA damage. Longicamphenylone was the prominent metabolite in response to seed deterioration. Pathway enrichment analysis revealed that flavonoid biosynthesis, which is involved in scavenging reactive oxygen species(ROS), was the most significant metabolic pathway associated with seed deterioration. Our findings also present the initial evidence linking endogenous antibiotics with seed aging.

Seed viability constants and the decline in germination rates for radish: a combined viability equation and population-based threshold model analysis

Aside from the leaves and roots, radish seedlings are consumed as a "microgreen". Production of microgreens requires high viability, high vigour seeds. Knowledge of the rates of loss of viability and vigour decline during storage would therefore be useful for radish sprout production, but also in relation to the conservation of radish germplasm in seed genebanks. Seeds of radish 'Kaiware', a microgreen cultivar, were stored hermetically at seven moisture levels between 6% and 13% at 50°C. Seed viability (germination after removal from storage) was scored daily to determine germination progress curves. One-step analysis was used to simultaneously fit the population-based threshold (PBT) model describing the decline in germination rates with ageing and to estimate the effects of MC on longevity according to the viability equation. KE and CW were estimated as 6.54 and 3.22, respectively. The ageing-time constant for the PBT model, age, increased as a function of storage moisture content, reflecting the faster decline in vigour at higher MC. The validity of the viability constants was tested by predicting viability loss in seeds of a different radish cultivar, 'Sango Purple', stored at 45°C and 8.61% MC.

Activity of α-d-Galactosidase in Long-Stored Seeds of Vicia hirsuta

Mature seeds of many crop species contain substantial amounts of soluble carbohydrates, including raffinose family oligosaccharides (RFOs) and cyclitol galactosides (Gal-C). These substances are hydrolysed by α-D-galactosidase (EC 3.2.1.22) during the early stages of germination, providing metabolic energy for the germination process. A decrease or inhibition of α-D-galactosidase activity can significantly reduce the germination rate. This study aimed to investigate changes in α-D-galactosidase activity during the long-term storage of Vicia hirsuta seeds and evaluate the association between the loss of enzyme activity and the decline in seed vigour and viability. V. hirsuta seeds were stored at 22 °C and 35% relative humidity for up to 25 years, and α-D-galactosidase activity and seed vigour changes were monitored at different time points. Storage of V. hirsuta seeds resulted in a loss of viability and vigour, accompanied by a decrease in α-D-galactosidase activity. The enzyme activity showed a significant correlation with seed germinability and vigour. Monitoring α-D-galactosidase activity in seeds subjected to long-term storage could be a simple and rapid method for determining the decline in vigour in seeds that utilize soluble galactosides as their storage materials.

The Influence of COVID-19 on University Students' Well-Being, Physical Activity, Body Composition, and Strength Endurance.

Very few scientific studies have simultaneously evaluated changes in well-being (WB), physical activity (PA), and strength endurance (SE) based on results from before and during the COVID-19 pandemic. The aim of the study was to assess WB, PA, and SE levels, as well as body composition parameters in university students before and during the pandemic. The study included 30 males and 30 females (mean age: 21.7 ± 2.51 and 21.6 ± 2.34 years, respectively). Well-being using the Self-Perception Questionnaire (POMS), PA from the Polish regular version of the International Physical Activity Questionnaire (IPAQ), body composition parameters using the InBody 270 analyzer, and SE based on the results of a 12 min test involving a Concept 2PM-5 rowing ergometer were assessed before and during the pandemic. An assessment of university students' WB revealed a significant increase in variables such as tension, depression, anger, confusion, and a significant decline in vigor (p < 0.05). In both sexes, PA and SE decreased significantly-from 2115.4 to 1822.8 METs-min/week and from 2184.5 to 2035 m, respectively, in males, and from 1793.5 to 1699.8 METs-min/week and from 2021.5 to 1943.8 m, respectively, in females. At the same time, body mass and BMI values increased significantly (p < 0.001) in both females and males. The COVID-19 pandemic caused a significant decrease in WB, PA and SE levels in young females and males, and led to a significant increase in their body mass and BMI.

Accumulation of somatic mutations leads to genetic mosaicism in cannabis.

Cannabis (Cannabis sativa L.) is typically propagated using stem cuttings taken from mother plants to produce genetically uniform propagules. However, producers anecdotally report that clonal lines deteriorate over time and eventually produce clones with less vigor and lower cannabinoid levels than the original mother plant. While the cause of this deterioration has not been investigated, one potential contributor is the accumulation of somatic mutations within the plant. To test this, we used deep sequencing of whole genomes (>50×) to compare the variability within an individual cannabis cultivar Honey Banana plant sampled at the bottom, middle, and top. We called over six million sequence variants based on a reference genome and found that the top had the most by a sizable amount. Comparing the variants among the samples uncovered that nearly 600,000 (34%) were unique to the top while the bottom only contained 148,000 (12%), and middle with 77,000 (9%) unique variants. Bioinformatics tools were used to identify mutations in critical cannabinoid-terpene biosynthesis pathways. While none were identified as high impact, four genes contained more than double the average level of nucleotide diversity (π) in or near the gene. Two genes code for essential enzymes required for the cannabinoid pathway while the other two are in the terpene pathways, demonstrating that mutations were accumulating within these pathways and could influence their function. Overall, a measurable number of intraplant genetic diversity was discovered that could impact long-term genetic fidelity of clonal lines and potentially contribute to the observed decline in vigor and cannabinoid content.

Tree-ring density and carbon isotope composition are early-warning signals of drought-induced mortality in the drought tolerant Canary Island pine

Tree death is not always preceded by a visible decline in vigor (canopy dieback) or a progressive loss in crown volume. Identifying early-warning signals of incipient decline can help to implement the necessary measures to prevent tree death. The aim of this work is to understand what functional alterations preceded the massive drought-induced death of adult Pinus canariensis trees in an arid stand, located in the Canary Islands. To this aim, we analyzed interannual variations in earlywood and latewood width, wood density and anatomy, and carbon isotope composition, and the relationships among these variables, in dead and living trees from 1980 to 2013. Dead trees grew less since the 1990′s, produced fewer parenchyma rays and resin canals, and exhibited a trend of decreasing latewood density and a marked shift in carbon isotope discrimination over the last 34 years that were reversed in living trees. Higher wood density in living trees resulted from thicker tracheid cell walls rather than narrower lumens. The intrinsic water use efficiency shifted from higher to lower values in dead trees after the 2000s. These results suggest a carbon limitation to maintain hydraulic safety under xylem tension, as well as to maintain storage and defense capacity, which can render trees more vulnerable to severe drought episodes. A long-term trend of decreasing tree-ring density and a reduced intrinsic water use efficiency in the short-term can be early-warning signals of carbon limitation and tree decline in drought-stressed P. canariensis. The analysis of these variables can be used to assess tree decline risks in similarly vulnerable conifer populations inhabiting drought-prone regions.

Infectious Clones of Tomato Chlorosis Virus: Toward Increasing Efficiency by Introducing the Hepatitis Delta Virus Ribozyme.

Tomato chlorosis virus (ToCV) is an emergent plant pathogen that causes a yellow leaf disorder in tomato and other solanaceous crops. ToCV is a positive-sense, single stranded (ss)RNA bipartite virus with long and flexuous virions belonging to the genus Crininivirus (family Closteroviridae). ToCV is phloem-limited, transmissible by whiteflies, and causes symptoms of interveinal chlorosis, bronzing, and necrosis in the lower leaves of tomato accompanied by a decline in vigor and reduction in fruit yield. The availability of infectious virus clones is a valuable tool for reverse genetic studies that has been long been hampered in the case of closterovirids due to their genome size and complexity. Here, attempts were made to improve the infectivity of the available agroinfectious cDNA ToCV clones (isolate AT80/99-IC from Spain) by adding the hepatitis delta virus (HDV) ribozyme fused to the 3′ end of both genome components, RNA1 and RNA2. The inclusion of the ribozyme generated a viral progeny with RNA1 3′ ends more similar to that present in the clone used for agroinoculation. Nevertheless, the obtained clones were not able to infect tomato plants by direct agroinoculation, like the original clones. However, the infectivity of the clones carrying the HDV ribozyme in Nicotiana benthamiana plants increased, on average, by two-fold compared with the previously available clones.

Optimization of Modified Murashige and Skoog (MS) Medium Promoting Efficient Callus Induction in Zinnia elegans

Zinnia (Zinnia elegans Jacq.) occupies a pristine place in the garden for its bright colours and long flowering period. Zinnias are propagated by seeds hence genetic variation and a tendency for stock plants to decline in vigor over time is high. Young internodal explants of this species were grown on modified Murashige and Skoog (MS) medium supplemented with various growth hormones to evaluate callus induction. 2,4 dichlorophenoxyacetic acid (2,4-D) at 1.0 mg/L was shown to be the best choice for a high percentage of callus induction (70-73%) and a rapid growth rate of viable and healthy callus. A large-scale and quick callus generation protocol was developed in the lab and might be used for in-vitro micropropagation.

Common features of aging fail to occur in Drosophila raised without a bacterial microbiome

SummaryLifespan is limited both by intrinsic decline in vigor with age and by accumulation of external insults. There exists a general picture of the deficits of aging, one that is reflected in a pattern of age-correlated changes in gene expression conserved across species. Here, however, by comparing gene expression profiling of Drosophila raised either conventionally, or free of bacteria, we show that ∼70% of these conserved, age-associated changes in gene expression fail to occur in germ-free flies. Among the processes that fail to show time-dependent change under germ-free conditions are two aging features that are observed across phylogeny, declining expression of stress response genes and increasing expression of innate immune genes. These comprise adaptive strategies the organism uses to respond to bacteria, rather than being inevitable components of age-dependent decline. Changes in other processes are independent of the microbiome and can serve as autonomous markers of aging of the individual.

RESPONSE OF DIFFERENT STORAGE CONTAINERS IN RICE GENOTYPES DURING STORAGE

Rice is the staple food of more than half the world’s population and is being cultivated in Asia since ancient time’s generation after generation. Good quality seeds are the seeds of the green revolution, it has been assertively and emphatically shown that 15-20% increased yield could be achieved by the use of good quality seeds alone. Good quality seed is one of the most important requirements for production and supply to achieve higher production and productivity in any crop. The seed quality is depended on various factors Viz. genetic, edaphic, environmental, biotic, etc. Good quality seed production depends on complex conditions evoking the most favorable interactions between the genetic makeup of the seed and the environment, under which it is produced, harvested, processed, and stored. Seeds undergo deterioration at various levels during storage resulting in a decline in vigor and viability. With the above considerations, the present investigation has been undertaken to observe the potentials of ten rice genotypes and observed its seed quality after harvesting in 2016-2017 at Seed Testing Laboratory, Department of Seed Science and Technology, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia, West Bengal, India. Just after harvesting G2 (Gobindabhog) and G9 (IR-36) showed highest germination percentage (97.66) and G9 (IR-36) showed highest Vigor index (3204.13). But most of the varieties germination and vigor were nearer to G2 &amp; G9. Among the containers with seed moisture content aluminum foil packet with seed moisture content, 8% is the best storage container for rice among the other containers as up to one-year storage vigor index was observed highest in that conditions.

Inbreeding Depression in Genotypically Matched Diploid and Tetraploid Maize.

The genetic and molecular basis of heterosis has long been studied but without a consensus about mechanism. The opposite effect, inbreeding depression, results from repeated self-pollination and leads to a reduction in vigor. A popular explanation for this reaction is the homozygosis of recessive, slightly deleterious alleles upon inbreeding. However, extensive studies in alfalfa indicated that inbreeding between diploids and autotetraploids was similar despite the fact that homozygosis of alleles would be dramatically different. The availability of tetraploid lines of maize generated directly from various inbred lines provided the opportunity to examine this issue in detail in perfectly matched diploid and tetraploid hybrids and their parallel inbreeding regimes. Identical hybrids at the diploid and tetraploid levels were inbred in triplicate for seven generations. At the conclusion of this regime, F1 hybrids and selected representative generations (S1, S3, S5, S7) were characterized phenotypically in randomized blocks during the same field conditions. Quantitative measures of the multiple generations of inbreeding provided little evidence for a distinction in the decline of vigor between the diploids and the tetraploids. The results suggest that the homozygosis of completely recessive, slightly deleterious alleles is an inadequate hypothesis to explain inbreeding depression in general.

A CRITICAL APPRAISAL ON AGEING PROCESS IN AYURVEDA

Ayurveda being essentially the science of life and longevity narrates all aspects of life and puts special emphasis on Jara (ageing). The world population of the elderly is increasing and by the year 2030, older persons are projected to account for one in six people globally. Ageing is a process of unfavorable progressive changes associated with decline in vigor and ending in death. It is an irreversible and inevitable process and has multidimensional aspects. Everyone must undergo this phase of life at his/her own life. In Ayurveda, Jara (ageing) is clearly defined as that which has lost age means become old by the act of degeneration of bodily tissues and organs. It is described of two types- Kalaja jara and Akalaja jara. The Kalaja jara (timely ageing) can be regarded as chronological ageing where Dhatukshaya occurs whereas the Akalajajara (premature ageing) which occurs untimely i.e., before its prescribed time it can be regarded as biological ageing and is more intense than that of the chronological ageing. Several concepts are reported in Ayurveda regarding ageing process e.g, decade wise ageing process is described by Acharya Vagbhat and Sharangdhara. According to them one particular bodily feature is being degraded by each decade of lifespan, in the same way multiple theories are also analyzed in contemporary science. The whole biology of ageing has been dealt in present article within the Ayurvedic frame.

Niche‐based relationship between sympatric bark living insect pests and tree vigor decline of Pinus yunnanensis

AbstractForest stands of Pinus yunnanensis Franch in southwestern China are seriously damaged by several bark living insect pests. These pests commonly exist in the same host tree and exploit limited phloem resources. In this study, we hypothesized that sympatric pests would occupy different ecological niches to reduce interspecific competition, and their coordinated attack would aggravate the tree vigor decline of P. yunnanensis. To quantify the ecological niches, we used a sampling method involving three dimensional divisions of tree resource states: (a) sample plot dimension (to evaluate the extent of pest colonization at plot scale), (b) trunk height dimension, and (c) tree vigor dimension. Those attacked pine canopies and colonized trunks were analysed in the field study. The results showed that Tomicus minor and Tomicus yunnanensis both widely and uniformly distributed in lightly, moderately and heavily damaged canopies while they aggregated on particular trunks of dying and withered trees. Lower and middle trunk sections (1–4 m) were mainly occupied by Monochamus alternatus and T. minor, yet T. yunnanensis dominated the upper parts (5–6 m). There was an overlap of the pine shoot beetles in the middle sections (2–4 m), whereas all three species were ecologically segregated in other trunk sections. During the shoot feeding phase, tree vigor declined with pine shoot beetles' increasing shoot feeding density. They coexisted in the same host tree, while M. alternatus only attacked dying and withered tree trunks, causing a greater infestation. Colonization of pine shoot beetle then followed by M. alternatus could be the major causes of tree mortality. This study highlights the resource utilization pattern of sympatric bark living insect pests corresponding with tree vitality. Those findings would help to understand the mechanisms of pest outbreak in P. yunnanensis ecosystem and provide potential guidance for developing an early monitoring pest warning system.

Hybrid Decay: A Transgenerational Epigenetic Decline in Vigor and Viability Triggered in Backcross Populations of Teosinte with Maize.

In the course of generating populations of maize with teosinte chromosomal introgressions, an unusual sickly plant phenotype was noted in individuals from crosses with two teosinte accessions collected near Valle de Bravo, Mexico. The plants of these Bravo teosinte accessions appear phenotypically normal themselves and the F1 plants appear similar to typical maize × teosinte F1s. However, upon backcrossing to maize, the BC1 and subsequent generations display a number of detrimental characteristics including shorter stature, reduced seed set, and abnormal floral structures. This phenomenon is observed in all BC individuals and there is no chromosomal segment linked to the sickly plant phenotype in advanced backcross generations. Once the sickly phenotype appears in a lineage, normal plants are never again recovered by continued backcrossing to the normal maize parent. Whole-genome shotgun sequencing reveals a small number of genomic sequences, some with homology to transposable elements, that have increased in copy number in the backcross populations. Transcriptome analysis of seedlings, which do not have striking phenotypic abnormalities, identified segments of 18 maize genes that exhibit increased expression in sickly plants. A de novo assembly of transcripts present in plants exhibiting the sickly phenotype identified a set of 59 upregulated novel transcripts. These transcripts include some examples with sequence similarity to transposable elements and other sequences present in the recurrent maize parent (W22) genome as well as novel sequences not present in the W22 genome. Genome-wide profiles of gene expression, DNA methylation, and small RNAs are similar between sickly plants and normal controls, although a few upregulated transcripts and transposable elements are associated with altered small RNA or methylation profiles. This study documents hybrid incompatibility and genome instability triggered by the backcrossing of Bravo teosinte with maize. We name this phenomenon "hybrid decay" and present ideas on the mechanism that may underlie it.

Tomato chlorosis virus, an emergent plant virus still expanding its geographical and host ranges

SummaryTomato chlorosis virus (ToCV) causes an important disease that primarily affects tomato, although it has been found infecting other economically important vegetable crops and a wide range of wild plants. First described in Florida (USA) and associated with a ‘yellow leaf disorder’ in the mid‐1990s, ToCV has been found in 35 countries and territories to date, constituting a paradigmatic example of an emergent plant pathogen. ToCV is transmitted semipersistently by whiteflies (Hemiptera: Aleyrodidae) belonging to the genera Bemisia and Trialeurodes. Whitefly transmission is highly efficient and cases of 100% infection are frequently observed in the field. To date, no resistant or tolerant tomato plants are commercially available and the control of the disease relies primarily on the control of the insect vector.Taxonomy Tomato chlorosis virus is one of the 14 accepted species in the genus Crinivirus, one of the four genera in the family Closteroviridae of plant viruses.Virion and genome propertiesThe genome of ToCV is composed of two molecules of single‐stranded positive‐sense RNA, named RNA1 and RNA2, separately encapsidated in long, flexuous, rod‐like virions. As has been shown for other closterovirids, ToCV virions are believed to have a bipolar structure. RNA1 contains four open reading frames (ORFs) encoding proteins associated with virus replication and suppression of gene silencing, whereas RNA2 contains nine ORFs encoding proteins putatively involved in encapsidation, cell‐to‐cell movement, gene silencing suppression and whitefly transmission.Host rangeIn addition to tomato, ToCV has been found to infect 84 dicot plant species belonging to 25 botanical families, including economically important crops.TransmissionLike all species within the genus Crinivirus, ToCV is semipersistently transmitted by whiteflies, being one of only two criniviruses transmitted by members of the genera Bemisia and Trialeurodes.Disease symptomsTomato ‘yellow leaf disorder’ syndrome includes interveinal yellowing and thickening of leaves. Symptoms first develop on lower leaves and then advance towards the upper part of the plant. Bronzing and necrosis of the older leaves are accompanied by a decline in vigour and reduction in fruit yield. In other hosts the most common symptoms include interveinal chlorosis and mild yellowing on older leaves.ControlControl of the disease caused by ToCV is based on the use of healthy seedlings for transplanting, limiting accessibility of alternate host plants that can serve as virus reservoirs and the spraying of insecticides for vector control. Although several wild tomato species have been shown to contain genotypes resistant to ToCV, there are no commercially available resistant or tolerant tomato varieties to date.

Ageing-induced changes in nutritional and anti-nutritional factors in cowpea (Vigna unguiculata L.).

This study examined the role of seed ageing in the control of anti-nutritional factors in cowpea (Vigna unguiculata L.). In differently aged seeds of three cultivars of V. unguiculata (V240, V78 and V585), germination ability and vigour were studied. Effort was also made to assay trypsin inhibitor, phenol and phytic acid, perform protein profiling in these seeds. High vigour lots (V240 and V585) registered maximum increases in germination of aged seeds. The contents of nutritional factors such as total protein and carbohydrate declined with decrease in seed vigour lots. Anti-nutritional factors such as phytic acid, phenolic content and trypsin inhibitor activity decreased and varied in low and high vigour seed lots. Polypeptide banding pattern significantly varied in the high, medium and low vigour seeds. Notably, proteins with the highest relative mobility of 0.98 and lowest molecular weight of 11.5kDa and lowest relative mobility of 0.17 and highest molecular weight of 102.0kDa were observed in all the vigour lots. Results implied the decline in vigour of V. unguiculata seeds under conditions of controlled ageing can be related to the decline in content of major nutritional factors (total carbohydrates and proteins) required for the growing embryo during seed germination. Additionally, decreases in the contents of anti-nutritional factors phytic acid and phenols, and the activity of trypsin inhibitor in particular are connected with the decrease in seed vigour irrespective of V. unguiculata cultivars. The use of short duration controlled ageing technique can, at least partially, reduce the negative effects of anti-nutritional factors, and eventually improve the nutritional quality of V. unguiculata seeds.

Protective Role of Mentha arvensis Aqueous Extract against Manganese Induced Toxicity by Reducing Mn Translocation and Promoting Antioxidative Defense in growing Indica Rice Seedlings

Mentha arvensis L. (Ma) leaf extract, a wide source of natural antioxidants is widely used to protect animal cells against oxidative stress. In the current study, we have studied the ameliorative effects of Ma leaf extract on Mn induced oxidative stress in rice (Oryza sativa L.) seedlings. Hydroponically grown rice seedlings treated with 1.5 mM MnCl2 showed a decline in vigour and contents of photosynthetic pigments, increased production of reactive oxygen species (O2˙‾, H2O2, and.OH), lipid peroxidation, protein thiol and carbonyl contents along with increased activity of antioxidative enzymes- superoxide dismutase (SOD), guaiacol peroxidase (GPX) and ascorbate peroxidase (APX). The activity of catalase (CAT), however, declined in the seedlings after prolonged Mn treatment of 8 days. Interestingly exogenous application of Ma leaf extract (638.4 mg ml-1) effectively restored the Mn-induced decline in seedling vigour, photosynthetic pigments, increased levels of H2O2, lipid peroxides and altered activities of antioxidative enzymes. The results indicate that exogenous application of Ma leaf extract significantly lowers the toxic effects of Mn in rice seedlings by modulating Mn translocation and reducing oxidative stress.

Weather-induced declines in piñon tree condition and response of a declining bird species

Climate impacts to piñon-juniper woodlands in the western USA include large-scale mortality, reduced canopy cover, and decreased cone production; recent climate models predict massive tree mortality in these woodlands. These habitat impacts will affect piñon-juniper wildlife, exemplified by the Pinyon Jay (Gymnorhinus cyanocephalus). Here we: (1) examine trends in an index of piñon tree condition (vigor) from 2004 to 2012, (2) assess the impact of weather and stand structure variables on annual vigor changes, and (3) investigate the relationship between patterns of piñon condition and distribution of nesting Pinyon Jays. Mean piñon vigor declined 0.12 units per year from 4.3 (maximum vigor = 5) in 2004 and bottomed out at 3.2 in 2012 (a reduction of 25.6%). Vigor changes were positive in areas of lower tree density and negative in areas of higher tree density; larger trees were more likely than smaller trees to decline in vigor. Average annual vigor decline was greater with decreasing cool-season precipitation. The probability that Pinyon Jays nested was higher in areas of higher piñon vigor in 2010–2012; this relationship became more pronounced over the three years. This example suggests that incremental, weather-influenced changes in tree condition may impact the wildlife of arid woodlands.

Effect of Anti-Oxidant in co-relation with Rasayana therapy of Ayurveda on Ageing

Ageing is a process of unfavorable progressive changes associated with decline in vigour and ending in death. Ageing is the part of life which is unavoidable but the untimely aging can be stopped. The process of ageing involves the coexistence of two opposing factor namely evolution (growth) and involution (atrophy). These processes continue to operate throughout the life but their importance varies in different age groups. As the age advanced, human beings gradually lose some of their attributes, because of functional and structural alteration in almost all organ systems. Ageing in individuals is affected to a greater extent by genetic factors, diet, social conditions and the occurrence of age related disorders. Anti oxidants can speed up the cell division and cell replacement process, which can help to slow the overall effects of ageing and prevent specific age related diseases. It also deactivates the free radicals and prevents their formation and also stimulates the immune system to increase our protection against all diseases. Like anti-oxidant in Ayurveda the Rasayana therapy not only helped attain longer, healthier life but also help cure some of the dreadful diseases. Rasayana aid in increasing natural immunity, enhancing general wellbeing, improving the functioning of all fundamental organs of the body and keep the signs of early ageing. The main purpose of Rasayana therapy is to impede the ageing process and to delay the degenerative process in the body.