scholarly journals The distribution of phospholipase D in developing and mature plants

1969 ◽  
Vol 112 (5) ◽  
pp. 787-794 ◽  
Author(s):  
R. H. Quarles ◽  
R. M. C. Dawson
Keyword(s):  
Phospholipase D ◽  
Dry Weight ◽  
Total Activity ◽  
Weight Basis ◽  
Carrot Root ◽  
Aerial Parts ◽  
Central Stalk ◽  
Pea Seeds ◽  
The Individual ◽  
Germination And Growth

1. The distribution of phospholipase D (phosphatidylcholine phosphatido-hydrolase, EC 3.1.4.4) was examined in the tissues of a number of plants and seeds. 2. The highest activities were found in various swollen storage tissues of certain plants: cabbage, central stalk; cauliflower, flower; celery, swollen leaf stalk; Kohl rabi, swollen stem; carrot, root; pea and marrow, seed. 3. Appreciable activity was retained in pea seeds for at least 1 year after drying. After germination and growth in the dark the total activity present in the cotyledons and also in the whole seedling decreased. 4. In the growing pea seedling (7 days old), about 3% of the total activity was in the plumule, 9% in the root and the remainder in the cotyledons. However, the activity in the root on a dry-weight basis was higher than that in the cotyledons. In both the root and the plumule the activity on a wet- or a dry-weight basis was highest in the growing tip. 5. The activity per dry weight in the roots and aerial parts of pea plants declined to low values as growth continued, but roots struck from cuttings of mature plants showed the same high activity as found in roots from young seedlings with cotyledons attached. 6. The total phospholipids present in the cotyledons of pea seeds were depleted on germination and growth. Of the individual phospholipids, phosphatidylcholine and phosphatidylethanolamine showed the same loss in 11 days as the whole phospholipid fraction, whereas phosphatidylinositol was decreased to a greater extent and cardiolipin and phosphatidylserine were not decreased. There was no increase of phosphatidic acid, as might have been expected if the phospholipids had disappeared through phospholipase D hydrolysis. 7. It is concluded that phospholipase D in plant storage tissues and seeds may be related to the rapid growth involved in their formation rather than being necessary for the utilization of their food reserve substances.

Total growth of a black spruce (Picea mariana) tree at Chalk River, Ontario, Canada

1969 ◽  
Vol 47 (1) ◽  
pp. 73-84 ◽  
Author(s):  
D. A. Fraser ◽  
D. McGuire
Keyword(s):  
Root Formation ◽  
Black Spruce ◽  
High Growth ◽  
Dry Weight ◽  
Productive Capacity ◽  
Annual Rings ◽  
Aerial Parts ◽  
Grand Total ◽  
Total Growth ◽  
The Individual

Apical and radial growth in trunk, branches, and roots, together with needle and cone distribution, were studied in a black spruce tree 31 years old and [Formula: see text] high. Growth of aerial parts was summarized as follows: (1) according to years of formation (oblique summation); (2) transversely on trunk inter-nodes (horizontal summation); and (3) according to the position of the annual rings, and the branch internodes (and needles) in relation to the pith or trunk (vertical summation). Root segments were classified on the basis of their diameter and distance from the trunk. Calculated on a dry-weight basis, the trunk accounted for 37%, the branches for 24%, the roots for 21%, and the needles for 18% of the grand total of 81 kg.The tree had 7.8 million needles when sampled in the fall of 1963, one-quarter of which were formed during the last 2 years of growth. Dry weight of individual needles varied with both position and age. While needles of the same season from the lower part of the crown exceeded those from the upper part in length, the reverse was true for the individual dry-weight content.In black spruce, cone periodicity, while distinct, is not as pronounced as in white spruce. The productive capacity of one "average" needle was estimated in terms of apical growth, trunk wood, and needle and root formation.

scholarly journals Essential Oil Composition of Thyme (Thymus zygioides Griseb. var. lycaonicus (Celak.) Ronniger) Wild Growing in Turkey

2020 ◽  
Vol 8 (1) ◽  
pp. 61
Author(s):  
Erman Duman ◽  
Mehmet Musa Özcan ◽  
Zrira Saadiab ◽  
Mustafa Mete Özcan
Keyword(s):  
Essential Oil ◽  
Dry Weight ◽  
Essential Oil Composition ◽  
Weight Basis ◽  
Geranyl Acetate ◽  
Oil Composition ◽  
Aerial Parts ◽  
Linalool Oxide ◽  
Main Components ◽  
Essential Oil Yield

The chemical composition of essential oil, which is isolated by hydrodistillation of aerial parts of Thymus zygioides growing wild in Turkey, have been determined by GC and GC/MS. Essential oil yield on a dry weight basis of aerial parts from T. zygioides was 0.45%. A total of twenty two constituents were identified by GC-MS analyses, the main components representing 92.3% the oil was identified as limonene (24.11%), cis-linalool oxide (22.91%), eucalyptol (8.65%). 3-octonol (7.04%), nerol (4.47%) geranyl acetate (3.19%), carvacrol (2.74%), linalyl propanoate (2.95%) and sabinene (2.23%). The essential oil of T. zygioides was characterized by its high content of limonene (24.11%).

scholarly journals The Effect of Mineral Nutrition on the Content of free Amino Acids and Amides in Tomato Plants II. A Study of the Effect of Molybdenum Nutrition

1957 ◽  
Vol 10 (1) ◽  
pp. 40 ◽  
Author(s):  
JV Possingham
Keyword(s):  
Amino Acids ◽  
Paper Chromatography ◽  
Mineral Nutrition ◽  
Free Amino Acids ◽  
Free Amino ◽  
Dry Weight ◽  
Experimental Period ◽  
Weight Basis ◽  
Tomato Plants ◽  
The Individual

Tomato plants which had been cultured in the absence of molybdenum were provided with molybdate, and the consequent changes in the relative amounts of the free amino acids and amides were followed over an experimental period of 4 days. The technique of quantitative paper chromatography was used to estimate the individual free amino acids and amides, and the results are .expressed on a dry weight basis.

ERRORS ASSOCIATED WITH HERBAGE DISSECTION ANALYSES 2. Problems of species identification

1976 ◽  
pp. 213-225
Author(s):  
I.M. Ritchie ◽  
C.C. Boswell ◽  
A.M. Badland
Keyword(s):  
New Zealand ◽  
Dry Weight ◽  
Analytical Tool ◽  
Species Level ◽  
Weight Basis ◽  
Plant Identification ◽  
Leaf Fragment ◽  
Research Division ◽  
Or Groups ◽  
Botanical Analysis

HERBACE DISSECTION is the process in which samples of herbage cut from trials are separated by hand into component species. Heavy reliance is placed on herbage dissection as an analytical tool ,in New Zealand, and in the four botanical analysis laboratories in the Research Division of the Ministry of Agriculture and Fisheries about 20 000 samples are analysed each year. In the laboratory a representative subsample is taken by a rigorous quartering procedure until approximately 400 pieces of herbage remain. Each leaf fragment is then identified to species level or groups of these as appropriate. The fractions are then dried and the composition calculated on a percentage dry weight basis. The accuracy of the analyses of these laboratories has been monitored by a system of interchanging herbage dissection samples between them. From this, the need to separate subsampling errors from problems of plant identification was, appreciated and some of this work is described here.

Polycyclic Aromatic Hydrocarbons (PAHs) in Sediments of the Brisbane River (Australia) – Preliminary Results

1989 ◽  
Vol 21 (2) ◽  
pp. 161-165 ◽  
Author(s):  
S. I. Kayal ◽  
D. W. Connell
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Aromatic Hydrocarbons ◽  
River Estuary ◽  
Dry Weight ◽  
Weight Basis ◽  
Sediment Samples ◽  
Preliminary Results ◽  
Treated Sewage ◽  
Polycyclic Aromatic ◽  
Petroleum Refineries

Results of the analysis of twenty-three composite sediment samples revealed that PAHs are widely distributed in the Brisbane River estuary. Mean concentrations for individual compounds, on a dry weight basis, ranged from 0.03 µg/g for dibenz [ah] anthracene to 2.34 µg/g for fluoranthene. Observed PAH assemblages were rich in compounds having pyrolytic origins. However, the presence of petroleum derived compounds was indicative of the importance of petroleum as a PAH source in the estuary. Petroleum refineries, a coal loading terminal and a major treated sewage outfall located at the mouth were not indicated as major contributing sources of PAH pollution in the estuary.

Mineral nutrition, dinitrogen fixation, and growth of Alnuscrispa and Alnusglutinosa

1985 ◽  
Vol 15 (5) ◽  
pp. 855-861 ◽  
Author(s):  
G. Prégent ◽  
C. Camiré
Keyword(s):  
Mineral Nutrition ◽  
Dry Weight ◽  
Optimal Growth ◽  
Maximum Growth ◽  
Dinitrogen Fixation ◽  
Weight Basis ◽  
Critical Levels ◽  
N Status

Invitro cultures of Alnuscrispa (Ait.) Pursh and Alnusglutinosa (L.) Gaertn. were used to estimate critical foliage levels of selected nutrients for optimal growth and dinitrogen (N2) fixation. For A. crispa to obtain 90% of maximum growth and N2 fixation, foliar levels of 0.12% P, 0.13% Mg, <0.31% K, and <0.04% Ca on a dry weight basis were needed. For A. glutinosa, the critical levels were 0.138% P, 0.10% Mg, 0.29% Ca, and ~0.20% K. From all the deficiencies observed, P had the more pronounced effects on N status of both species.

SOLUBLE SUGAR CHANGES OCCURRING DURING COLD HARDENING OF SPRING WHEAT, FALL RYE AND ALFALFA

1983 ◽  
Vol 63 (2) ◽  
pp. 415-420 ◽  
Author(s):  
D. G. GREEN
Keyword(s):  
Spring Wheat ◽  
Soluble Sugar ◽  
Soluble Sugars ◽  
Dry Weight ◽  
Weight Basis ◽  
Cold Hardening ◽  
Spring Type

Alfa, a relatively nonhardy alfalfa cultivar continued to accumulate, on a dry weight basis, fructose, α- and β-D-glucose, sucrose and maltose during the latter stages of cold hardening. Rambler, a hardier alfalfa cultivar conversely showed a decrease for these soluble sugars with hardening. Frontier rye, a very hardy winter habit cereal showed decreases in these soluble sugars plus melibiose during the same hardening period. These results support the hypothesis that hardy cereals and alfalfa undergo a decrease in soluble sugars with hardening, while less hardy cereals and alfalfa continue to increase in content of soluble sugars. Manitou wheat appeared not to fit this hypothesis and showed the decreased soluble sugars usually associated with hardy cultivars. Although Manitou is a spring type wheat, one of its parents, Thatcher, does contain gene(s) for the winter habit.Key words: Sugar, cold hardening, wheat, rye, alfalfa

scholarly journals THE MOLECULAR WEIGHT OF RHODOPSIN AND THE NATURE OF THE RHODOPSIN-DIGITONIN COMPLEX

1954 ◽  
Vol 37 (3) ◽  
pp. 381-399 ◽  
Author(s):  
Ruth Hubbard
Keyword(s):  
Molecular Weight ◽  
Single Molecule ◽  
Extinction Coefficient ◽  
Dry Weight ◽  
Weight Basis ◽  
Sedimentation Behavior ◽  
A Value ◽  
Wet Weight ◽  
Single Boundary ◽  
Stoichiometric Complex

The sedimentation behavior of aqueous solutions of digitonin and of cattle rhodopsin in digitonin has been examined in the ultracentrifuge. In confirmation of earlier work, digitonin was found to sediment as a micelle (D-1) with an s20 of about 6.35 Svedberg units, and containing at least 60 molecules. The rhodopsin solutions sediment as a stoichiometric complex of rhodopsin with digitonin (RD-1) with an s20 of about 9.77 Svedberg units. The s20 of the RD-1 micelle is constant between pH 6.3 and 9.6, and in the presence of excess digitonin. RD-1 travels as a single boundary also in the electrophoresis apparatus at pH 8.5, and on filter paper at pH 8.0. The molecular weight of the RD-1 micelle lies between 260,000 and 290,000. Of this, only about 40,000 gm. are due to rhodopsin; the rest is digitonin (180 to 200 moles). Comparison of the relative concentrations of RD-1 and retinene in solutions of rhodopsin-digitonin shows that RD-1 contains only one retinene equivalent. It can therefore contain only one molecule of rhodopsin with a molecular weight of about 40,000. Cattle rhodopsin therefore contains only one chromophore consisting of a single molecule of retinene. It is likely that frog rhodopsin has a similar molecular weight and also contains only one chromophore per molecule. The molar extinction coefficient of rhodopsin is therefore identical with the extinction coefficient per mole of retinene (40,600 cm.2 per mole) and the E(1 per cent, 1 cm., 500 mµ) has a value of about 10. Rhodopsin constitutes about 14 per cent of the dry weight, and 3.7 per cent of the wet weight of cattle outer limbs. This corresponds to about 4.2 x 106 molecules of rhodopsin per outer limb. The rhodopsin content of frog outer limbs is considerably higher: about 35 per cent of the dry weight, and 10 per cent of the wet weight, corresponding to about 2.1 x 109 molecules per outer limb. Thus the frog outer limb contains about five hundred times as much rhodopsin as the cattle outer limb. But the relative volumes of these structures are such that the ratio of concentrations is only about 2.5 to 1 on a weight basis. Rhodopsin accounts for at least one-fifth of the total protein of the cattle outer limb; for the frog, this value must be higher. The extinction (K500) along its axis is about 0.037 cm.2 for the cattle outer limb, and about 0.50 cm.2 for the frog outer limb.

Influence of Temperature and Water Activity on Aflatoxin Production by Aspergillus flavus in Cowpea (Vigna unguiculata) Seeds and Meal

1985 ◽  
Vol 48 (12) ◽  
pp. 1040-1043 ◽  
Author(s):  
P. E. KOEHLER ◽  
L. R. BEUCHAT ◽  
M. S. CHHINNAN
Keyword(s):  
Heat Treatment ◽  
Water Activity ◽  
Aspergillus Flavus ◽  
Vigna Unguiculata ◽  
Dry Weight ◽  
Aflatoxin Production ◽  
Weight Basis ◽  
Influence Of Temperature

Experiments were done to determine the influence of temperature (21, 30 and 37°C) and aw (0.76 to 0.98) on aflatoxin production by Aspergillus flavus on cowpea (Vigna unguiculata) seeds, meal and meal supplemented with onion. Larger quantities of aflatoxin were produced at 21 and 30°C than at 37°C. The highest amount of aflatoxin (2777 μg/20 g, dry weight basis) was observed in meal containing onion at aw 0.98 after 20 d of incubation at 21°C. A level of 870 |μg/20 g was detected in seeds at aw 0.95 after 14 d of incubation at 30°C. Meal at aw 0.96 supported production of 551 μg of aflatoxin per 20 g after 20 d at 30° C. Temperature had little influence on the optimal aw for aflatoxin production in cowpea meal. However, an increase in temperature resulted in a decreased optimal aw for aflatoxin production on whole cowpeas. When known quantities of aflatoxin were added to cowpea meal which was subsequently steamed for 5 min, only 29% was extractable using a variety of procedures, indicating that the toxin may be bound in some manner to cowpea constituents as a result of heat treatment.

Low K+ in Paphiopedilum leeanum leaf epidermis: implications for stomatal functioning

1977 ◽  
Vol 55 (4) ◽  
pp. 489-495 ◽  
Author(s):  
Sherman D. Nelson ◽  
James M. Mayo
Keyword(s):  
Dry Weight ◽  
Atomic Absorption Spectrophotometry ◽  
Weight Basis ◽  
Leaf Epidermis ◽  
Photometric Analysis ◽  
Abaxial Epidermis ◽  
Absorption Spectrophotometry ◽  
Stomatal Functioning ◽  
Low K ◽  
Stomatal Mechanism

Abaxial epidermal strips from leaves of Paphiopedilum leeanum were analyzed via sodium cobaltinitrite staining and atomic absorption spectrophotometry for the presence and location of potassium. On a dry weight basis K content of the abaxial epidermis was found to be 103 times less than has been reported in other species, and unlike other species no localization of K+ in guard cells of open stomata could be detected via the sodium cobaltinitrite stain for potassium.Flame photometric analysis of the mesophyll indicated that it contained normal amounts of K+ (about 1.87% on a dry weight basis). Analysis showed that the K+ content of the abaxial epidermis (0.032%) was considerably less than that of the mesophyll, a situation unlike previous reports for other species in which the epidermal concentration was found to be greater than the mesophyll. A process for exclusion of K+ from the abaxial epidermis is suggested, as is the lack of involvement of K+ as the major osmoticum in the stomatal mechanism of this species.

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