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Start Over Creator Vats, S. K.

1. A Himalayan monsoonal location exhibiting unusually high preponderance of C4 grasses

Creator:
Rama Das, V. S. and Vats, S. K.
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
An unexpectedly large proportion of C4 grasses was found in a moderately temperate and moist Himalayan location during monsoon period. 79 % of total grasses occurring in the area were found to be C4. Several grasses hitberto unreported as C4 háve now been recorded. The principál cause for the natural abundance of C4 species is presumably low atmospheric CO2 levels rallua' tlian the aridity and warmer temperatures. The finding adds a new dimension to our knowledge of natural distribution of the C4 species.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2. CO2 sequestration in plants: lesson from divergent strategies

Creator:
Vats, S. K., Kumar, S., and Ahuja, P. S.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
botanika, botany, aquatic, carbon-concentrating mechanisms, crasssulacean acid metabolism, C4 photosynthesis, and Rubisco
Language:
Multiple languages
Description:
Most organisms inhabiting earth feed directly or indirectly on the products synthesized by the reaction of photosynthesis, which at the current atmospheric CO2 levels operates only at two thirds of its peak efficiency. Restricting the photorespiratory loss of carbon and thereby improving the efficiency of photosynthesis is seen by many as a good option to enhance productivity of food crops. Research during last half a century has shown that several plant species developed CO2-concentrating mechanism (CCM) to restrict photorespiration under lower concentration of available CO2. CCMs are now known to be operative in several terrestrial and aquatic plants, ranging from most advanced higher plants to algae, cyanobacteria and diatoms. Plants with C4 pathway of photosynthesis (where four-carbon compound is the first product of photosynthesis) or crassulacean acid metabolism (CAM) may consistently operate CCM. Some plants however can undergo a shift in photosynthetic metabolism only with change in environmental variables. More recently, a shift in plant photosynthetic metabolism is reported at high altitude where improved efficiency of CO2 uptake is related to the recapture of photorespiratory loss of carbon. Of the divergent CO2 assimilation strategies operative in different oraganisms, the capacity to recapture photorespiratory CO2 could be an important approach to develop plants with efficient photosynthetic capacity. and S. K. Vats, S. Kumar, P. S. Ahuja
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Gas exchange response of barley and pea cultivars to altitude variation in Himalaya

Creator:
Vats, S. K., Kumar, N., and Kumar, S.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
acclimation, Hordeum, photosynthesis, Pisum, pore length, species differences, stomatal conductance, stomatal density, and stomatal index
Language:
Multiple languages
Description:
Leaf stomatal density (SD), net photosynthetic rates (PN), and stomatal conductance (gs) of Hordeum vulgare and Pisum sativum cultivars in Himalaya increased with altitude. Higher PN and leaf temperature under low CO2 partial pressure at high altitudes could evoke a higher gs and SD to allow sufficient influx of CO2 as well as more efficient leaf cooling through transpiration. and S. K. Vats, N. Kumar, S. Kumar.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. Photosynthetic response of Podophyllum hexandrum Royle from different altitudes in Himalayan ranges

Creator:
Vats, S. K. and Kumar, S.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
efficiency of carbon uptake, intercellular CO2 concentration, and stomatal conductance
Language:
Multiple languages
Description:
Plants of Podophyllum hexandrum, collected from lower, mid, and upper distribution limits in alpine Himalaya were studied under greenhouse conditions to evaluate the photosynthetic response. Net photosynthetic rates (PN), stomatal conductance (gs), and efficiency of carbon uptake increased with altitude. The maximum PN and gs were measured in the considered population during the 3-6th week of development. PN and gs decreased on an average by 58 and 48 % from maximum rates reached around 4th week to the 10th week of growth, respectively. The photosynthetic response in the three ecotypes appeared to be genetically controlled. and S. K. Vats, S. Kumar.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5. Photosynthetic response to irradiance in Valeriana jatamansi Jones, a threatened understorey medicinal herb of Western Himalaya

Creator:
Vats, S. K., Pandey, S., and Nagar, P. K.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
acclimation, chlorophyll, photosynthetic photon flux density, and shade
Language:
Multiple languages
Description:
Net photosynthetic rate (PN) of Valeriana jatamansi plants, grown under nylon net shade or under different tree canopies, was saturated with photons at 1 000 μmol m-2 s-1 photosynthetic photon-flux-density (PPFD), whereas open-grown plants were able to photosynthesise even at higher PPFD, e.g. of 2 000 μmol m-2 s-1. Plants grown under net shade had higher total chlorophyll (Chl) content per unit area of leaf surface. However, Chl a/b ratio was maximal in open-grown plants, but remained unchanged in plants grown in nylon net shade and under different tree canopies. Sun-grown plants had thicker leaves (higher leaf mass per leaf area unit), higher wax content, and higher PN than shade grown plants. Thus V. jatamansi is able to acclimate to high PPFD and therefore this Himalayan species may be cultivated in open habitat to meet the ever-increasing industrial demand. and S. K. Vats, S. Pandey, P. K. Nagar.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public