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5042. VanToai, T., Major, D., McDonald, M., Schepers, J., Tarpley, L. (ed.): Digital imaging and spectral techniques: applications to precision agriculture and crop physiology
- Creator:
- Nedbal, L.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- plant science
- Language:
- Multiple languages
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5043. Variability of the photosynthetic machinery tolerance when imposed to rapidly or slowly imposed dehydration in native Mediterranean plants
- Creator:
- Koutra, E., Chondrogiannis, C., and Grammatikopoulos, G.
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- drought factor index, integrated biomarker response, JIP-test, photosynthesis, plant growth forms, and water stress
- Language:
- Multiple languages
- Description:
- Dehydration affects the photosynthetic apparatus. The impact of dehydration on photosynthesis was assessed in twelve Mediterranean species representing different growth forms. Rapid and slow dehydration experiments were conducted to (1) compare the impact of water stress among species and growth forms, (2) rank species according to their drought tolerance. Rapid dehydration reduced the electron transport up to PSI, the reduction being linearly related to leaf relative water content (RWC), except for the deciduous species. Specific energy fluxes per reaction center and maximum photochemical activity of PSII remained relatively stable until 10-30% RWC. The modification pattern of the studied parameters was similar for all the growth forms. Slow rehydration increased specific energy fluxes and decreased quantum yields. The dehydration pattern was similar among growth forms, while the recovery pattern was species-specific. Drought tolerance ranking through drought factor index was relatively modified with the integrated biomarker response method.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5044. Variable responses of mesophyll conductance to substomatal carbon dioxide concentration in common bean and soybean
- Creator:
- Bunce, J. A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, Glycine max, light, Phaseolus vulgaris, and temperature
- Language:
- Multiple languages
- Description:
- Some reports indicate that mesophyll conductance (gm) to carbon dioxide varies greatly with the substomatal carbon dioxide concentration (Ci) during the measurement, while other reports indicate little or no change in g m with Ci. I used the oxygen sensitivity of photosynthesis to determine the response of gm to Ci over the range of about 100 to 300 μmol mol-1 Ci at constant temperature in common bean (Phaseolus vulgaris) and soybean (Glycine max) grown over a range of temperatures and photosynthetic photon flux densities (PPFD). In soybean grown and measured at high PPFD there was only a slight, approximately 15% decrease in gm with Ci over the range of 100 to 300 μmol mol-1. With lower PPFD during the measurement of gm, and especially with low PPFD during plant growth, there was a larger decrease in gm with Ci in soybean. In common bean, the same range in Ci resulted in about a 60% decrease in g m for plants grown and measured at high PPFD, with an even larger decrease for plants at low growth or measurement PPFD. Growth temperatures of 20 to 30°C had little influence on the response of gm to Ci or its absolute value in either species. It is concluded that these two species differed substantially in the sensitivity of gm to Ci, and that PPFD but not temperature during leaf development strongly affected the response of gm to Ci. and J. A. Bunce.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5045. Variation in carbonic anhydrase activity and its relationship with photosynthesis and dry mass of mustard
- Creator:
- Khan, N.A.
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Multiple languages
- Description:
- Carbonic anhydrase (CA) activity and net photosynthetic rate (/’N) in the leaves, and plant dry mass (DM) in twelve cultivars of mustard (Brassica juncea L.) were measured 50, 70 and 90 d after sowing. At different sampling stages CA was strongly associated with PN and DM.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5046. Variation in leaf photosynthetic characteristics in wild rice species
- Creator:
- Kiran, T. V., Rao, Y. V., Subrahmanyam, D., Rani, N. S., Bhadana, V. P., Rao, P. R., and Voleti, S. R.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, gas exchange, rice, specific leaf area, specific leaf mass, stomatal conductance, wild rice, 2, and 581
- Language:
- Multiple languages
- Description:
- Variations in leaf gas-exchange characteristics, leaf pigment content, and other important leaf traits were investigated in seven wild Oryza species, five hybrids, and five improved varieties. The significant variations were observed in photosynthetic pigment contents amongst different species of Oryza. The mean chlorophyll (Chl) content was higher in O. sativa (varieties and hybrids), while O. eichengeri showed the lowest Chl content. The mean carotenoid (Car) content in O. sativa (varieties and hybrids) was higher than in other wild rice species. O. eichengeri and O. barthii had significantly lower Car contents than other rice species. Significant differences were noticed in the rate of photosynthesis (PN), stomatal conductance (gs), transpiration rate (E), internal CO2 concentration (Ci), specific leaf mass (SLM), and leaf thickness amongst different Oryza species. The mean PN was the highest in O. nivara followed by O. eichengeri. The mean PN was the lowest in O. glumaepatula, which was lower than that of cultivated varieties and hybrids of O. sativa. High rates of photosynthesis were observed in O. nivara (ACC. No. CR 100097), O. rufipogon (ACC.No. CR 100267), and O. nivara (ACC.No. CR 100008). The O. nivara and O. rufipogon genotypes with high PN might be used in rice improvement programmes for an increase of leaf photosynthesis in rice. Multiple correlations performed between different gas-exchange characteristics and other physiological traits revealed that the rate of photosynthesis was not dependent on the leaf pigment content or the leaf thickness. A strong positive correlation between PN and the PN/Ci ratio, which represents the carboxylation efficiency, indicated that the observed variation in PN was not based on pigment content or other leaf traits. and T. V. Kiran ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5047. Variation in photosynthetic characteristics and leaf area contributes to Spathiphyllum cultivar differences in biomass production
- Creator:
- Wang, Qibing and Chen, Jianjun
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- biomass, chlorophyll content, intercellular CO2 concentration, leaf area and thickness, net photosynthetic rate, ornamental foliage plants, peace lily, stomatal conductance, and water-use efficiency
- Language:
- Multiple languages
- Description:
- Three genetically related Spathiphyllum cultivars, Claudia, Double Take, and Petite with similar initial sizes and biomass, were grown in a shaded greenhouse and fertilized with a constant supply of nitrogen at 200 g m-3 using an ebb-and-flow fertigation system. Seven months later, Claudia and Double Take had plant sizes and biomasses significantly greater than Petite. Stomatal conductances of Claudia and Double Take were 30 % greater, thus net photosynthetic rates (PN) were significantly higher than in Petite. In addition, the leaf areas (LA) of Claudia and Double Take were 60 % larger than of Petite. Since PN was expressed per leaf surface area, the greater the LA was, the more CO2 was fixed. Thus, the differences in plant size and biomass production of Claudia and Double Take compared to Petite are attributed to high PN and increased LA. and Qibing Wang, Jianjun Chen.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5048. Variation in photosynthetic rates and biomass productivity among four mulberry cultivars
- Creator:
- Chaitanya, K. V., Masilamani, S., Jutur, P. P., and Ramachandra Reddy, A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- branches, chlorophyll, DCPIP photoreduction, glucose, Morus, ribulose-1,5-bisphosphate carboxylase, shoot, starch, sucrose, and sucrose phosphate synthase
- Language:
- Multiple languages
- Description:
- Among four mulberry (Morus alba L.) cultivars (K-2, MR-2, BC2-59, and S-13), highest net photosynthetic rate (PN) was observed in BC2-59 while the lowest rates were recorded with K-2. Significant differences among the four cultivars were found in leaf area, biomass production, activities of ribulose-1,5-bisphosphate carboxylase and sucrose phosphate synthase, and glucose and sucrose contents. The PN and the activities of photosynthetic enzymes in the four cultivars were significantly correlated with the growth and biomass production measured as leaf yield, total shoot mass, and aerial plant biomass. and K. V. Chaitanya ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5049. Variation in structural and physiological leaf traits of eight species in karst desertification area of China
- Creator:
- Wei, L.-Y., Zeng, D.-J., Lv, S.-H., Zhang, J.-L., Jiao, J.-F., You, Y.-M., and Li, X.-K.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, desertification, dry biomass, karst area, leaf area, photosynthesis, and specific leaf area
- Language:
- Multiple languages
- Description:
- Leaf traits have long been recognized as influential factors in the acquisition and processing of resources by plants. However, there is less knowledge of between-species variations in seasonal changes in leaf traits and trait interrelationships. Therefore, we examined variations in leaf area (LA), dry biomass (DM), specific leaf area (SLA), and leaf gas-exchange parameters in one non-native and seven native tree species under field environmental conditions, in a karst area in China subjected to desertification. Measurements were taken three times during the growing season. The results show that the seven native trees had higher LA, DM, and water-use efficiency (WUE) than the non-native Cinnamomum camphora. In contrast, all the native tree species except Ligustrum lucidum had lower photosynthetic rates (PN) than the non-native species. In all species, the relationship between LA and DM was less variable than the relationship between SLA and LA. However, leaves of the non-native C. camphora and native species Sterculia lanceolata, Cleidiocarpon cavalerei and Cyclobalanopsis glauca were highly sensitive to seasonal conditions, leaves of Sapindus mukorossi and Ligustrum lucidum were less sensitive to seasonal changes, and leaves of Syzygium cumini and Cephalomappa sinensis were insensitive. An understanding of leaf traits will aid the selection of suitable species for land restoration. and L.-Y. Wei ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5050. Variation of photosynthetic characteristics and yield in wild and cultivated species of yams (Dioscorea spp.) from Koraput, India
- Creator:
- Padhan, B. and Panda, D.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, chlorophyll fluorescence, gas exchange, tuber yield, 2, and 581
- Language:
- Multiple languages
- Description:
- Variations in leaf gas-exchange characteristics, PSII activity, leaf pigments, and tuber yield were investigated in seven wild and one cultivated species of Dioscorea from Koraput, India, in order to find out their overall adaptability to the environment. The leaf photosynthetic rate, transpiration, stomatal conductance, water-use efficiency, carboxylation efficiency, and photosynthetic pigments were significantly higher in some wild species compared to the cultivated species. In addition, some wild species showed better photochemical efficiency of PSII, photochemical quenching, and electron transport rate in comparison to cultivated one. Furthermore, leaf dry matter accumulation and tuber yield was also higher in some wild species compared to the cultivated species. Taken together, the wild species, such as D. oppositifolia, D. hamiltonii, and D. pubera, showed the superior photosynthetic efficiency compared to the cultivated D. alata and they could be used for future crop improvement programs., B. Padhan, D. Panda., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public