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Start Over Subject botanika Date Unknown

235. Nitrogen enhanced photosynthesis of Miscanthus by increasing stomatal conductance and phosphoenolpyruvate carboxylase concentration

Creator:
Feng, X.-P., Chen, Y., Qi, Y.-H., Yu, C.-L., Zheng, B.-S., Brancourt-Hulmel, M., and Jiang, D.-A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
botanika, botany, bundle sheath leakiness of CO2, leaf mass per unit area, nitrogen-use efficiency, Rubisco, 2, and 58
Language:
Multiple languages
Description:
Miscanthus is one of the most promising bioenergy crops with high photosynthetic nitrogen-use efficiency (PNUE). It is unclear how nitrogen (N) influences the photosynthesis in Miscanthus. Among three Miscanthus genotypes, the net photosynthetic rate (PN) under the different light intensity and CO2 concentration was measured at three levels of N: 0, 100, and 200 kg ha-1. The concentrations of chlorophyll, soluble protein, phosphoenolpyruvate carboxylase (PEPC), ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) large subunit, leaf anatomy and carbon isotope discrimination (Δ) in the leaf were analyzed to probe the response of photosynthesis in Miscanthus genotypes to N levels. PN in all genotypes rose significantly as N application increased. The initial slope of response curves of PN to Ci was promoted by N application in all genotypes. Both stomatal conductance and Ci were increased with increased N supply, indicating that stomatal factors played an important role in increasing PN. At a given Ci, PN in all genotypes was enhanced by N, implying that nonstomatal factors might also play an important role in increasing PN. Miscanthus markedly regulated N investment into PEPC rather than the Rubisco large subunit under higher N conditions. Bundle sheath leakiness of CO2 was constant at about 0.35 for all N levels. Therefore, N enhanced the photosynthesis of Miscanthus mainly by increasing stomatal conductance and PEPC concentration., X.-P. Feng ... [et al.]., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

236. Nondestructive determination of nitrogen and chlorophyll content in olive tree leaves and the relation with photosynthesis and fluorescence parameters

Creator:
Boussadia, O., Steppe, K., Zgallai, H., Ben el Hadj, S., Braham, M., Lemeur, R., and Van Labeke, M. C.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
botanika, botany, electron flow, nitrogen deficiency, olive tree, photosynthesis, pigments, SPAD-502, and quantum yield
Language:
Multiple languages
Description:
For Tunisian olive tree orchards, nitrogen deficiency is an important nutritional problem, in addition to the availability of water. Establishment of relationships between nutrients such as nitrogen and ecophysiological parameters is a promising method to manage fertilisation at orchard level. Therefore, a nitrogen stress experiment with one-year-old olive trees (Olea europaea L. 'Koroneiki' and 'Meski') was conducted with trees respectively subjected to four nitrogen supply regimes (23.96 meq l-1, 9.58 meq l-1, 4.79 meq l-1 and 0 meq l-1 NO3-). The current paper focuses on the use of the SPAD-502 portable chlorophyll (Chl) meter, a nondestructive method for fertilisation management under nitrogen stress conditions of olive trees. Maximum net photosynthetic assimilation rates, chlorophyll fluorescence parameters and the SPAD Chl index were therefore measured simultaneously and the Chl and nitrogen content of the leaves were analysed. Significant correlations were established in the olive tree leaves between SPAD-502 readings on the one hand and Chl content, nitrogen content, photosynthetic assimilation rate, and Chl fluorescence parameters (ΦPSII and ETR) on the other hand. and O. Boussadia ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

237. Nondestructive leaf-area estimation and validation for green pepper (Capsicum annuum L.) grown under different stress conditions

Creator:
Cemek, B., Unlukara, A., and Kurunc, A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
botanika, botany, green pepper, irrigation regime, irrigation water salinity, leaf area estimation, and nondestructive metods
Language:
Multiple languages
Description:
Leaf area of a plant is essential to understand the interaction between plant growth and environment. This useful variable can be determined by using direct (some expensive instruments) and indirect (prediction models) methods. Leaf area of a plant can be predicted by accurate and simple leaf area models without damaging the plant, thus, provide researchers with many advantages in horticultural experiments. Several leaf-area prediction models have been produced for some plant species in optimum conditions, but not for a plant grown under stress conditions. This study was conducted to develop leaf area estimation models by using linear measurements such as lamina length and width by multiple regression analysis for green pepper grown under different stress conditions. For this purpose, two experiments were conducted in a greenhouse. The first experiment focused to determine leaf area of green pepper grown under six different levels of irrigation water salinity (0.65, 2.0, 3.0, 4.0, 5.0, and 7.0 dS m-1) and the other under four different irrigation regime (amount of applied water was 1.43, 1.0, 0.75, and 0.50 times of required water). In addition to general models for each experiment, prediction models of green pepper for each treatment of irrigation water salinity and of irrigation regime experiments were obtained. Validations of the models for both experiments were realized by using the measurements belong to leaf samples allocated for validation purposes. As a result, the determined equations can simply and readily be used in prediction of leaf area of green pepper grown under salinity and water stress conditions. The use of such models enable researchers to measure leaf area on the same plants during the plant growth period and, at the same time, may reduce variability in experiments. and B. Cemek ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

238. Nondestructive, simple, and accurate model for estimation of the individual leaf area of som (Persea bombycina)

Creator:
Chattopadhyay, S., Tikader, A., and Das, N. K.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
botanika, botany, leaf area prediction, leaf length, leaf width, nondestructive methods, regression model, and validation
Language:
Multiple languages
Description:
Nondestructive approach of modeling leaf area could be useful for plant growth estimation especially when number of available plants is limited and/or experiment demands repeated estimation of leaf area over a time scale. A total of 1,280 leaves were selected randomly from eight different morphotypes of som (Persea bombycina) established at randomized complete block design under recommended cultural regimes in field. Maximum leaf laminar width (B), length (L) and their squares B2, L2; leaf area (LA), and lamina length × width (L×B) were determined over two successive seasons. Leaf parameters were significantly affected by morphotypes; but seasons had nonsignificant impacts on tested features. Therefore, pooled seasonal morphotype means of each parameter were used to establish relationship with LA. L and its square L2 did not provide accurate models for LA predictions. Considerably better models were obtained by using B (y = 2.984 + 7.9664 x, R2 = 0.615, P≥0.001, n = 119) and B2 (y = 12.784+ 0.9604 x, R2 = 0.605, P≥0.001, n = 119) as independent variables. However, maximum accuracy of prediction of LA could be achieved through a simple linear relationship of L×B (y = 8.2203 + 0.4224 x, R2 = 0.843, P≥0.0001, n = 119). The model (LA:L×B) was validated with randomly selected leaf samples (n = 360) of som morphotypes and highly significant (P≤0.001) linear function was found between actual and predicted LAs. Therefore, the last model may consider adequate to predict leaf area of all cultivars of som with sufficient fidelity. and S. Chattopadhyay ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

239. Nová, hezká, německá a česká :

Creator:
Strnadová, Lucie,
Type:
text and studie
Subject:
Vysoké školy, Čelakovský, Ladislav,, zahrady botanické, univerzity, učitelé vysokoškolští, vztahy česko-německé, botanika, české země 1848-1914, vědy o živé přírodě, Němci, česko-německé vztahy, and dějiny vědeckých institucí, vysokých škol
Language:
Czech
Description:
New, beautiful, German and Czech: The Division of university Botanical Garden in Prague (1882-1898).
Rights:
unknown

240. Nové lokality sklenobýlu bezlistého v Krkonoších - dárek k 50. výročí existence KRNAP?

Creator:
Pavla Čížková, Kamila Lencová, and Hubený, Pavel
Format:
print
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Botanika, Správa Krkonošského národního parku, botanika, vstavačovité, botany, orchids, 2, and 58
Language:
Czech
Description:
Sklenobýl bezlistý (Epipogium aphyllum) patří mezi nejvzácnější druhy naší flóry. Roste v bučinách a jehličnatých lesích s humózní půdou, často na lesních prameništích. Ještě donedávna byl v Čechách hodnocen jako nezvěstný. V r. 2006 se ale podařilo objevit několik malých lokalit na Šumavském Boubíně, poté v r. 2008 i jedna lokalita v Krkonoších. V červnu r. 2013 v náplavech Jizery a hned u cesty nedaleko Kořenova se podařilo objevit další dvě mikrolokality tohoto ohroženého druhu. Bylo by velmi povzbuzující domnívat se, že nárůst počtu lokalit nejen sklenobýlu, ale i jiných ohrožených druhů indikuje zlepšující se stav prostředí., Epipogium aphyllum is one of the rarest plant species of the Czech flora. It grows in humus-rich soil in beech and spruce forests, often in the vicinity of forest springs. The species has been considered missing in Bohemia until recent discoveries of a few sites in Boubín in the Šumava Mts. (Bohemian Forest, 2006) and in the Krkonoše Mts. (Giant Mts., 2008). Two new populations were found in the Giant Mts. in June 2013 - in alluvial deposits of the Jizera river and along the forest road close to the Kořenov village., and Pavla Čížková, Kamila Lencová, Pavel Hubený.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public