Role of Moisture Stress in Plant Nutritional Functions

1990 ◽  
pp. 453-474 ◽  
Author(s):  
J.F. POWER
Keyword(s):  
Moisture Stress

Corrigendum - Studies on presowing drought hardening of wheat

1969 ◽  
Vol 20 (1) ◽  
pp. 13
Author(s):  
DR Woodruff
Keyword(s):  
Grain Yield ◽  
Arid Zone ◽  
Moisture Stress ◽  
Phenological Stage ◽  
Transient Effect ◽  
Hardening Treatment ◽  
Relative Water ◽  
Leaf Relative Water Content ◽  
Drought Hardening

The effects of presowing drought hardening of wheat on subsequent leaf relative water content (RWC) and grain yield were assessed under a number of environmental conditions. In general, the treatment reduced the rate at which critical levels of RWC developed during periods of moisture stress, but not necessarily the final value to which the RWC fell. No differences were found in any of the measured parameters during periods when there were no internal water deficits. Grain yield increases due to the hardening treatment varied "from 0 to 20%" in the different experiments. This variation is explained in terms of both the phenological stage at which RWC differences occurred and the transient effect of the RWC differences. The results are also discussed in relation to both the cause of the observed RWC differences and the potential practical role of the technique in arid zone agriculture.

Role of mucilage in seed dispersal and germination of the annual ephemeral Alyssum minus (Brassicaceae)

2012 ◽  
Vol 60 (5) ◽  
pp. 439 ◽  
Author(s):  
Ying Sun ◽  
Dun Y. Tan ◽  
Carol C. Baskin ◽  
Jerry M. Baskin
Keyword(s):  
Water Stress ◽  
Seed Dispersal ◽  
Incubation Temperature ◽  
Water Reservoir ◽  
Soil Surface ◽  
Moisture Stress ◽  
West China ◽  
North West ◽  
Seed Age

Seeds of Alyssum minus, an annual ephemeral in shrublands of north-west China, can produce a large amount of mucilage. The primary aim of this study was to explore the role of mucilage in seed dispersal, settlement onto the soil surface and germination of this species. Width of imbibed seeds with mucilage was three times greater than that of seeds without mucilage, and mass of mucilage increased 167 times after imbibition. Expanded dry mucilage significantly increased wind dispersal of seeds. Floating time on water was greatest for seeds without mucilage, and adherence of soil particles to seeds was greater for seeds with mucilage than for those without mucilage. Mucilage increased rate of water uptake and decreased rate of water loss, and it significantly decreased germination of 0- and 4-week-old seeds. Gibberellic acid promoted germination of 0- and 4-week-old seeds with and without mucilage, but its effect depended on seed age and incubation temperature. Seeds with mucilage subjected to water stress during imbibition and/or incubation germinated faster than those without mucilage. Presence of mucilage on seeds during imbibition significantly increased germination percentages under increased water stress, a first report of this phenomenon. The study has shown that the mucilage of A. minus plays an important role in seed dispersal, seed adhesion to soil (thereby minimising removal by water and predators), seed hydration via increasing surface contact with the substrate, and can serve as a water reservoir for germination, especially under moisture stress.

REHABILITATION OF DEGRADED GRASSLANDS IN NORTH SYRIA: THE USE OF AWASSI SHEEP TO DISPERSE THE SEEDS OF ANNUAL PASTURE LEGUMES

1998 ◽  
Vol 34 (4) ◽  
pp. 391-405 ◽  
Author(s):  
F. GHASSALI ◽  
A. E. OSMAN ◽  
P. S. COCKS
Keyword(s):  
Seed Size ◽  
Maximum Rate ◽  
Moisture Stress ◽  
Faecal Pellets ◽  
Pasture Legumes ◽  
Awassi Sheep ◽  
Naturally Occurring ◽  
Legume Seeds ◽  
Rate Of Recovery

Four experiments were conducted to facilitate the improvement of degraded grasslands in north Syria. The first examined the survival of legume seeds fed to penned Awassi wethers. The second and third observed the germination and establishment of legumes from faecal pellets in the field and in a glasshouse respectively. The fourth explored the possibility of transporting seeds from legume-rich (source) to legume-poor (target) grasslands using commercial flocks on communally-owned land. Seeds of small-seeded clovers passed through sheep in greater numbers (58–72%) than did seeds of larger-seeded species (10–40%). Of the clover seeds Trifolium campestre (seed size 0.45 mg) disintegrated least (72% passage) and T. haussknechtii (seed size 2.68 mg) disintegrated most (10% passage). Recoveries of Medicago noeana and Scorpiurus muricatus seeds were larger than expected on the basis of their seed sizes. Maximum rate of recovery was at 36 h after the seed meal for all species, all seeds were recovered by 120 h and 90% of the recovered seeds were passed in 72 h. Ingestion had little effect on the hardness and viability of most seeds. Experiments 2 and 3 suggested that seeds in pellets germinated and established as successfully as naked seeds. Burial increased establishment, whether in the field or under conditions of low moisture stress in the glasshouse. The small-seeded clovers, T. tomentosum and T. campestre, established most successfully whether from pellets or from naked seeds. About 500 seeds m−2 were successfully transported from the source to the target grassland. About half were Trigonella monspeliaca, a naturally-occurring legume found on both the source and target grasslands. Of the species sown on the source grassland, 115 seeds m−2 of Trifolium campestre (33% of the source seed bank), 62 seeds m−2 of T. tomentosum (27%) and 78 seeds m−2 of T. purpureum (21%) were detected in the target. Few medics were transported (for example, <2% of M. noeana). Apart from Trigonella monspeliaca, Trifolium tomentosum (16 plants m−2) was the most frequent species found in the target grassland in the following April. The results suggest that using sheep is a cheap and practical way of dispersing the seeds of pasture legumes and thereby improving the degraded grasslands of north Syria. They clearly demonstrate the role of small-seeded legumes (<1 mg) in grassland improvement, especially the small-seeded clovers.

Studies on presowing drought hardening of wheat

1969 ◽  
Vol 20 (1) ◽  
pp. 13
Author(s):  
DR Woodruff
Keyword(s):  
Grain Yield ◽  
Arid Zone ◽  
Moisture Stress ◽  
Phenological Stage ◽  
Transient Effect ◽  
Hardening Treatment ◽  
Relative Water ◽  
Leaf Relative Water Content ◽  
Drought Hardening

The effects of presowing drought hardening of wheat on subsequent leaf relative water content (RWC) and grain yield were assessed under a number of environmental conditions. In general, the treatment reduced the rate at which critical levels of RWC developed during periods of moisture stress, but not necessarily the final value to which the RWC fell. No differences were found in any of the measured parameters during periods when there were no internal water deficits. Grain yield increases due to the hardening treatment varied "from 0 to 20%" in the different experiments. This variation is explained in terms of both the phenological stage at which RWC differences occurred and the transient effect of the RWC differences. The results are also discussed in relation to both the cause of the observed RWC differences and the potential practical role of the technique in arid zone agriculture.

Revealing the Effects of Potassium on Rice Roots under Moisture Stress

2018 ◽  
Vol 102 (4) ◽  
pp. 28-31
Author(s):  
Kirti Bardhan ◽  
Dipika Patel ◽  
Dhiraji Patel
Keyword(s):  
Drought Stress ◽  
Drought Tolerance ◽  
Root Architecture ◽  
Plant Root ◽  
Moisture Stress ◽  
Rice Roots ◽  
Aerial Parts ◽  
Organ Level ◽  
Plant Root System

The role of K in providing drought tolerance in the aerial parts of plants at the cellular, molecular, tissue, and organ level is well established compared to the plant root system. However, it is known that plants acquire soil water from deeper layers by modifying root architecture. The current study investigated the role of K in changing root architecture to facilitate more water acquisition as a mechanism to mitigate drought stress.

scholarly journals Role of Beneficial Microorganisms and Salicylic Acid in Improving Rainfed Agriculture and Future Food Safety

2020 ◽  
Vol 8 (7) ◽  
pp. 1018 ◽  
Author(s):  
Naeem Khan ◽  
Asghari Bano ◽  
José Alfredo Curá
Keyword(s):  
Organic Matter ◽  
Salicylic Acid ◽  
Plant Growth ◽  
Rhizosphere Soil ◽  
Combined Treatment ◽  
Moisture Stress ◽  
Growth And Yield ◽  
Growth Promoting ◽  
Aba Content

Moisture stress in rainfed areas has significant adverse impacts on plant growth and yield. Plant growth promoting rhizobacteria (PGPR) plays an important role in the revegetation and rehabilitation of rainfed areas by modulating plant growth and metabolism and improving the fertility status of the rhizosphere soils. The current study explored the positive role of PGPR and salicylic acid (SA) on the health of the rhizosphere soil and plants grown under rainfed conditions. Maize seeds of two different varieties, i.e., SWL-2002 (drought tolerant) and CZP-2001 (drought sensitive), were soaked for 4 h prior to sowing in 24-h old culture of Planomicrobium chinense strain P1 (accession no. MF616408) and Bacillus cereus strain P2 (accession no. MF616406). The foliar spray of SA (150 mg/L) was applied on 28-days old seedlings. The combined treatment of the consortium of PGPR and SA not only alleviated the adverse effects of low moisture stress of soil in rainfed area but also resulted in significant accumulation of leaf chlorophyll content (40% and 24%), chlorophyll fluorescence (52% and 34%) and carotenoids (57% and 36%) in the shoot of both the varieties. The PGPR inoculation significantly reduced lipid peroxidation (33% and 23%) and decreased the proline content and antioxidant enzymes activities (32% and 38%) as compared to plants grown in rainfed soil. Significant increases (>52%) were noted in the contents of Ca, Mg, K Cu, Co, Fe and Zn in the shoots of plants and rhizosphere of maize inoculated with the PGPR consortium. The soil organic matter, total nitrogen and C/N ratio were increased (42%), concomitant with the decrease in the bulk density of the rhizosphere. The PGPR consortium, SA and their combined treatment significantly enhanced the IAA (73%) and GA (70%) contents but decreased (55%) the ABA content of shoot. The rhizosphere of plants treated with PGPR, SA and consortium showed a maximum accumulation (>50%) of IAA, GA and ABA contents, the sensitive variety had much higher ABA content than the tolerant variety. It is inferred from the results that rhizosphere soil of treated plants enriched with nutrients content, organic matter and greater concentration of growth promoting phytohormones, as well as stress hormone ABA, which has better potential for seed germination and establishment of seedlings for succeeding crops.

Role of dactinomycin in the improved survival of children with Wilms' tumor

JAMA ◽  
1966 ◽  
Vol 195 (12) ◽  
pp. 1005-1009 ◽  
Author(s):  
D. J. Fernbach
Keyword(s):  
Wilms Tumor

Role of the allergist in diagnosis and management of patients with uveitis

JAMA ◽  
1966 ◽  
Vol 195 (3) ◽  
pp. 167-172 ◽  
Author(s):  
T. E. Van Metre
Keyword(s):  
Diagnosis And Management

The power of norms to sway fused group members

2018 ◽  
Vol 41 ◽  
Author(s):  
Winnifred R. Louis ◽  
Craig McGarty ◽  
Emma F. Thomas ◽  
Catherine E. Amiot ◽  
Fathali M. Moghaddam
Keyword(s):  
Evolutionary Anthropology ◽  
Normative Systems ◽  
Violent Extremism ◽  
Identity Fusion ◽  
Group Members

AbstractWhitehouse adapts insights from evolutionary anthropology to interpret extreme self-sacrifice through the concept of identity fusion. The model neglects the role of normative systems in shaping behaviors, especially in relation to violent extremism. In peaceful groups, increasing fusion will actually decrease extremism. Groups collectively appraise threats and opportunities, actively debate action options, and rarely choose violence toward self or others.

Sign in / Sign up

Export Citation Format

Share Document