scholarly journals Changes in intracellular and extracellular amino acids during the predation of the chlorophyte Dunaliella primolecta by the heterotrophic dinoflagellate Oxyrrhis marina and the use of the glutamine/glutamate ratio as an indicator of nutrient status in mixed populations

1989 ◽  
Vol 53 ◽  
pp. 117-127 ◽  
Author(s):  
KJ Flynn ◽  
J Fielder
Keyword(s):  
Amino Acids ◽  
Nutrient Status ◽  
Heterotrophic Dinoflagellate ◽  
Oxyrrhis Marina ◽  
Mixed Populations

scholarly journals Zinc and amino acids impact on nutrient status of maize during the ‘critical window’

2018 ◽  
Vol 64 (No. 3) ◽  
pp. 126-131
Author(s):  
Szczepaniak Witold ◽  
Potarzycki Jarosław ◽  
Grzebisz Witold ◽  
Nowicki Bartłomiej
Keyword(s):  
Amino Acids ◽  
Nutritional Status ◽  
Nutrient Status ◽  
Kernel Weight ◽  
Simultaneous Application ◽  
Critical Window ◽  
Combined Application ◽  
Beneficial Impact ◽  
Yield Depression ◽  
Yield Decrease

It has been assumed that zinc (Zn) fertilizers applied to maize simultaneously with amino acids (AA) at early stages of its growth may decrease the yield variability due to correcting its nutritional status during the ‘critical window’. Two Zn carriers were evaluated (Zn-I – Zn chelate; Zn-II – Zn oxide); they were applied to maize at BBCH 14/15 with or without amino acids, based on two rates of nitrogen (80 and 160 kg N/ha). The precipitation deficiency in 2015 resulted in the grain yield decrease by 35% compared to 2014. An advantage of higher N rate was proved in 2014, whereas the influence of Zn and AA showed in 2015. In this year, the beneficial impact of Zn-oxide and AA combined application resulted in amelioration, at least partially, of the imbalance of certain macronutrient content (N, P, Mg) during the ‘critical window’. These effects were revealed due to a boosted number of kernels in cob, and particularly higher thousand kernel weight. Consequently, the yield depression in 2015 was partly overcome. The results indicated that simultaneous application of Zn oxide and AA to maize at BBCH 14/15 corrected both its nutritional status during the ‘critical window’ and yield components, but had no effect on the yield itself.

scholarly journals Taxonomy and Physiology of Oxyrrhis marina and Oxyrrhis maritima in Korean Waters

Water ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2057
Author(s):  
Min Kyoung Jung ◽  
Tae Yeon Yin ◽  
Seung Joo Moon ◽  
Jaeyeon Park ◽  
Eun Young Yoon
Keyword(s):  
Coastal Waters ◽  
Phylogenetic Trees ◽  
High Salinity ◽  
Ssu Rdna ◽  
Heterotrophic Dinoflagellate ◽  
Korean Waters ◽  
Oxyrrhis Marina ◽  
Lipid Contents ◽  
High Lipid ◽  
Characterization Studies

The genus Oxyrrhis is a heterotrophic dinoflagellate found in diverse marine environments. Oxyrrhis spp. have received attention owing to their ecological and industrial importance, high lipid contents, and docosahexaenoic acid formation. To the best of our knowledge, contrary to O. marina, ecophysiological characterization studies on O. maritima have not yet been reported. Therefore, we investigated the taxonomy and ecophysiology of four strains of O. marina from coastal waters and two strains of O. maritima from the littoral tidepool waters of Korea. Based on phylogenetic trees constructed using internal transcribed spacer ribosomal DNA (ITS rDNA) and SSU rDNA of dinoflagellates, the clade of all four O. marina strains was divergent from that of the two O. maritima strains. We measured the growth rates of both species at various water temperatures (10–36 °C), salinities (5–90), and light intensities (0–100 µE·m−2·s−1). The lowest (O. marina and O. maritima: 10 °C) and highest temperatures (O. marina: <35 °C, O. maritima: >35 °C) revealed that O. maritima has more tolerance to high salinity. This study provides a basis for understanding the ecophysiology of O. marina and O. maritima and their population dynamics in marine ecosystems.

Growth and photosynthetic down-regulation in Coffea arabica in response to restricted root volume

2006 ◽  
Vol 33 (11) ◽  
pp. 1013 ◽  
Author(s):  
Cláudio P. Ronchi ◽  
Fábio M. DaMatta ◽  
Karine D. Batista ◽  
Gustavo A. B. K. Moraes ◽  
Marcelo E. Loureiro ◽  
...  
Keyword(s):  
Amino Acids ◽  
Coffea Arabica ◽  
Nutrient Status ◽  
Starch Phosphorylase ◽  
Down Regulation ◽  
Root Shoot Ratio ◽  
Fructose 1,6 Bisphosphatase ◽  
Coffee Plants ◽  
Root Restriction ◽  
Source Sink

Coffee (Coffea arabica L.) plants were grown in small (3-L), medium (10-L) and large (24-L) pots for 115 or 165 d after transplanting (DAT), which allowed different degrees of root restriction. Effects of altered source : sink ratio were evaluated in order to explore possible stomatal and non-stomatal mechanisms of photosynthetic down-regulation. Increasing root restriction brought about large and general reductions in plant growth associated with a rising root : shoot ratio. Treatments did not affect leaf water potential or leaf nutrient status, with the exception of N content, which dropped significantly with increasing root restriction even though an adequate N supply was available. Photosynthesis was severely reduced when plants were grown in small pots; this was largely associated with non-stomatal factors, such as decreased Rubisco activity. At 165 DAT contents of hexose, sucrose, and amino acids decreased in plants grown in smaller pots, while those of starch and hexose-P increased in plants grown in smaller pots. Photosynthetic rates were negatively correlated with the ratio of hexose to free amino acids, but not with hexose content. Activities of acid invertase, sucrose synthase, sucrose-P synthase, fructose-1,6-bisphosphatase, ADP-glucose pyrophosphorylase, starch phosphorylase, glyceraldehyde-3-P dehydrogenase, PPi : fructose-6-P 1-phosphotransferase and NADP : glyceraldehyde-3-P dehydrogenase all decreased with severe root restriction. Glycerate-3-P : Pi and glucose-6-P : fructose-6-P ratios decreased accordingly. Photosynthetic down-regulation was unlikely to have been associated directly with an end-product limitation, but rather with decreases in Rubisco. Such a down-regulation was largely a result of N deficiency caused by growing coffee plants in small pots.

Saprophytic and phagocytic isolates of the colourless heterotrophic dinoflagellate Gyrodinium lebouriae Herdman

1977 ◽  
Vol 57 (2) ◽  
pp. 303-315 ◽  
Author(s):  
Robert Edward Lee
Keyword(s):  
Electron Microscope ◽  
Structural Level ◽  
Heterotrophic Dinoflagellate ◽  
Free Living ◽  
Oxyrrhis Marina ◽  
The Third ◽  
Show Evidence ◽  
Noctiluca Miliaris ◽  
Short Time ◽  
Comprehensive Study

Nutritionally, there are three basic types of Dinophyceae: (1) free-living photosynthetic autotrophs; (2) parasitic heterotrophs living on or in other organanisms and (3) free-living phagocytic or chemosynthetic heterotrophs. Representatives of the first type, the free-living photosynthetic autotrophic species, have been extensively investigated at the fine-structural level (for a review see Dodge, 1971). There are fewer species of the second type, the parasitic Dinophyceae, but many of these have been investigated in the electron microscope (Cachon & Cachon, 1966, 1970, 1971a, b; Cachon et al. 1968; Soyer, 1969 c; Manier, Fize & Grizel, 1971; Siebert & West, 1974). The third type, the free-living heterotrophic Dinophyceae, probably comprises the greatest number of species in the class; as Kofoid & Swezy (1921) state ‘One cannot work with the marine unarmored Dinoflagellata for even a short time without being struck by the fact that the majority of the individuals observed show evidence of holozoic nutrition and that the number actually containing chromatophores is relatively small throughout the entire Dinoflagella’. While the free-living heterotrophic Dinophyceae comprise the largest proportion of the class they have been, by far, the most poorly studied at the fine structural level. Investigations on these organisms have been limited to a comprehensive study of Oxyrrhis marina (Dodge & Crawford, 1971a, b, 1974) plus studies on specific parts of Cryptothecodinium cohnii (Kubai & Ris, 1969; Pokorny & Gold, 1973) and Noctiluca miliaris (Afzelius, 1963; Soyer, 1968, 1969a, b; Zingmark, 1970).

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