scholarly journals The influence of nitrogen nutrition on the dynamics of growth and metabolism of endogenous growth regulators in Scotch pine (Pinus silvestris L.) seedlings

2015 ◽  
Vol 45 (4) ◽  
pp. 495-510
Author(s):  
M. Michniewicz ◽  
B. Rożej ◽  
J. Stopińska
Keyword(s):  
Dry Matter ◽  
Shoot Growth ◽  
Nitrogen Nutrition ◽  
Lateral Roots ◽  
Scotch Pine ◽  
Pine Seedlings ◽  
Nitrogen Treatment ◽  
Positive Effect ◽  
Growth Of Seedlings ◽  
Stimulation Of

Pine seedlings were cultivated in sterile agar cultures containing nitrogen as NH4Cl. The most pronounced positive effect on the growth of seedlings was affected by N used at a concentration of 50 ppm. After 4 months was stated that nitrogen had only a slight effect on elongation, of .shoots but decreased the length of roots. Nitrogen increased the lenght and number of primary and secondary needles as well as the fresh and dry matter of sboots. It stimulated also the number of lateral roots and the fresh and dry matter of the root system. Stimulation of shoot growth and differentiation as a result of nitrogen treatment was correlated with the increase -of free gibberellins and auxins and decrease of the amount of bound gibberellins and ABA-like inhibitor in shoots. However the effect of N on growth of roots was connected with the increase of auxins, cytokinins and ABA-like inhibitor in these organs.

scholarly journals The effect of potassium nutrition on growth and on plant hormones content in Scots pine (Pinus silvestris L.) seedlings

2014 ◽  
Vol 49 (3) ◽  
pp. 235-244 ◽  
Author(s):  
Marian Michniewicz ◽  
Jadwiga Stopińska
Keyword(s):  
Dry Matter ◽  
Growth Inhibitor ◽  
Plant Tissues ◽  
Pinus Silvestris ◽  
Fresh Weight ◽  
Potassium Nutrition ◽  
Pine Seedlings ◽  
Leafy Shoots ◽  
Positive Effect ◽  
Growth Of Seedlings

Pine seedlings were cultivated in Ingestad nutrient solution containing potassium as KCl on a 16-hr day, under light intensity of about 4000 lx and temperature of about 23° C. K+ used in a concentration of 50 ppm exerted a most pronounced positive effect on the growth of seedlings. After 4 months it was found that potassium used in this concentration increased elongation of hypocotyls, shoots, roots, primary and secondary needles as well as fresh weight and dry matter of tissues. In leafy shoots K+ increased the level of free gibberelirns (GAs) and auxins and decreased the amount of bound GAs and an ABA-like inhibitor. In the roots K+ nutrition increased the amount of free GAs and of the growth inhibitor and decreased the level of bound GAs and auxins. No evident influence of K+ on the level of cytokinins in plant tissues was stated.

The growth of lodgepole pine seedlings raised under clear polythene cloches at five seedbed densities

1980 ◽  
Vol 10 (3) ◽  
pp. 426-428
Author(s):  
S. Thompson
Keyword(s):  
Plant Height ◽  
Dry Matter ◽  
Shoot Growth ◽  
Lodgepole Pine ◽  
Unit Length ◽  
Dry Weight ◽  
Dry Matter Production ◽  
Matter Production ◽  
Pine Seedlings ◽  
Foliage Weight

The components of shoot growth and dry matter production in 1 + 0 lodgepole pine (Pinuscontorta Dougl. ex Loud. spp. contorta) seedlings raised under clear polythene cloches for 12 weeks at five seedbed densities (180–720 plants/m2) were studied. The greater plant height found at the highest seedbed density was the result of increased stem unit length, not increased number of stem units. The increase in plant dry weight as seedbed density decreased was largely due to greater dry weight of roots, branchwood, and branch foliage, and not to increases in stemwood and stem foliage weight. Seedbed densities of less than 460 seedlings/m2 are required to produce yields of suitably sturdy seedlings in excess of 50% of the crop.

scholarly journals The role of vanillin and p-coumaric acid in the growth of Scotch pine seedlings

2015 ◽  
Vol 43 (2) ◽  
pp. 273-281 ◽  
Author(s):  
M. Michniewicz ◽  
E. Galoch
Keyword(s):  
Phenolic Compounds ◽  
Dry Weight ◽  
Coumaric Acid ◽  
Scotch Pine ◽  
Growth Processes ◽  
Plant Organs ◽  
Pine Seedlings ◽  
Stimulation Of

It was stated that vanillin and p-coumaric acid used at concentrations 10<sup>-8</sup>-10<sup>-5</sup>M stimulated the growth of pine seedlings. Most effective were these substances used at concentration 10<sup>-7</sup>M. Both phenolic compounds stimulated the elongation, fresh and dry weight in very young seedlings (up to 3-4 weeks) and increased the fresh and dry weight only in older ones (7 weeks). The stimulation of growth processes in pine seedlings treated with vanillin and p-coumaric acid coincided with the increase of auxins in roots and with the decrease of free gibberellins in these plant organs. Neither vanillin nor p-coumaric acid influenced the level of ABA-like inhibitor both in the shoots and roots of pine seedlings.

scholarly journals EFFECT OF PSEUDOMONAS PROTEGENS DA1.2 IN COMBINATION WITH HERBICIDES ON THE HORMONAL SYSTEM AND PRODUCTIVITY OF SOFT SPRING WHEAT IN THE CONDITIONS OF THE TRANS URAL STEPPE ZONE

ÈKOBIOTEH ◽  
2021 ◽  
Vol 4 (4) ◽  
pp. 276-281
Author(s):  
A.V. Feoktistova ◽  
◽  
M.D. Timergalin ◽  
T.V. Rameev ◽  
Z.R. Sultangazin ◽  
...  
Keyword(s):  
Spring Wheat ◽  
Growth And Development ◽  
Shoot Growth ◽  
Steppe Zone ◽  
Soil Drought ◽  
Combined Stress ◽  
Relative Water ◽  
Hormonal System ◽  
Positive Effect ◽  
Stimulation Of

This article presents data on the effect of a new growth-regulating bacterial strain Pseudomonas protegens DA1.2 on the productivity of soft spring wheat when treated with chyalan and nanomet herbicides under the conditions of the Trans-Ural steppe zone. The introduction of bacteria together with herbicides led to the accumulation of mass and stimulation of shoot growth, as well as maintaining a high relative water content in the leaves. In combinations of bacterial treatments with nanomet, an increased content of ABA and a decrease in the level of IAA in shoots were noted. Together with chistalan, the ABA concentration in the shoots decreased. The ability of bacterial treatments to increase the yield of wheat under conditions of combined stress caused by the action of herbicides and soil drought, due to the positive effect of bacteria on the growth and development of plants, was revealed.

scholarly journals The effect of nitrogen nutrition on growth and on plant hormones content in Scots pine (Pinus silvestris L.) seedlings grown under light of different intensity

2014 ◽  
Vol 49 (3) ◽  
pp. 221-134 ◽  
Author(s):  
Marian Michniewicz ◽  
Jadwiga Stopińska
Keyword(s):  
Light Intensity ◽  
Water Content ◽  
Plant Hormones ◽  
Nitrogen Nutrition ◽  
Lateral Roots ◽  
Growth Stimulation ◽  
N Nutrition ◽  
Pine Seedlings ◽  
Effect Of Light

Pine seedlings were cultivated in the Ingested nutrient solution containing N as NH<sub>4</sub>Cl at concentrations of 0 and 500 ppm, under a 16-hr day, at a light intensity of 1500 and 500 lx and temperature ± 20°C. Measurements of seedlings and determination of plant hormones were performed 8 weeks after sowing. It was found that more intensive light stimulated initiation of needles and lateral roots as well as elongation of needles and roots, and increased the fresh weight and dry matter of these organs. Growth stimulation of needles was correlated with an increase in free gibberellins, cytokinins, an ABA-like inhibitor and with a decrease in auxins and water content of tissues. A similar effect of light on plant hormones (except ABA) was also observed in roots. The level of this inhibitor depended on N nutrition. Nitrogen bad a similar effect as light on the growth and initiation of needles and lateral roots. However, it strongly inhibited elongation of roots and increased the water content of the tissues. In needles N increased the level of GAs and auxins, under both light variants, as well as the level of cytokinins, under more intensive light. It decreased the amount of ABA-like inhibitor. In roots the effect of N nutrition on the level of plant hormones depended upon the light intensity. Under light of low intensity N decreased the level of GAs and ABA, increased the level of auxins and had nonsignificant influence on the level of cytokinins. Under more intensive light it had no effect on the GAs and auxin levels and increased the level of cytoikinins and the ABA-like inhibitor.

scholarly journals Evaluation of Physical Barriers to Protect Ponderosa Pine Seedlings from Pocket Gophers

1999 ◽  
Vol 14 (3) ◽  
pp. 164-168 ◽  
Author(s):  
Michael J. Pipas ◽  
Gary W. Witmer
Keyword(s):  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Seedling Mortality ◽  
Pocket Gophers ◽  
Thomomys Talpoides ◽  
Pine Seedlings ◽  
Physical Barriers ◽  
Growth Of Seedlings ◽  
Medium Weight ◽  
Better Than

Abstract A 2 yr study on the Rogue River and Mt. Hood National Forests in Oregon evaluated physical barriers for protection of Pinus ponderosa seedlings against damage by Thomomys talpoides. Seedlings protected with one of three weights of: (1) plastic mesh tubing (Vexar®) or (2) sandpapertubing (Durite®) were evaluated against control seedlings. On the Rogue River sites, Vexar® seedlings had the highest survival (62.6%), followed by the controls (59.1%), then Durite® seedlings (17.9%). Gophers were the primary cause of death for the Vexar® seedlings, versus desiccation for the Durite® seedlings. On the Mt. Hood sites, heavyweight Vexar® seedlings had the highest survival (35.4%), medium-weight Durite® seedlings the lowest (2.7%). Seedling mortality caused by gophers was highest for controls (70.2%), followed by light-weight (62.2%) and heavy-weight (53.9%) Vexar® treatments. Overall survival was low (Rogue River = 42%, Mt. Hood = 19.8%). Growth was greatest for the control seedlings but only significantly greater than growth of Durite® seedlings on the Rogue River sites. Growth of seedlings was not compromised by the Vexar® tubing. Although neither type of tubing was highly protective, Vexar® tubes performed better than Durite® tubes. West. J. Appl. For. 14(3):164-168.

EFFECTS OF DESICCATED THYROID ON NON-ESTROGENIZED AND ESTROGENIZED SEXUALLY IMMATURE PULLETS

1960 ◽  
Vol 40 (2) ◽  
pp. 119-125 ◽  
Author(s):  
A. J. Moo-Young ◽  
K. A. McCully ◽  
R. H. Common
Keyword(s):  
Intramuscular Injection ◽  
Crude Protein ◽  
Dry Matter ◽  
Estradiol Benzoate ◽  
Kidney Weight ◽  
Total Crude Protein ◽  
Stimulation Of ◽  
Liver Tissues

Inclusion of 0.5 per cent desiccated thyroid in the food of unestrogenized immature pullets for 14 days reduced thyroid weight, reduced serum Ca slightly but significantly, increased liver total crude protein, liver total DNAP and total RNAP, but did not alter the ratio RNAP:DNAP in the liver. These results are regarded as indicative of stimulation of growth of liver tissues by the thyroidal treatment.Daily intramuscular, injection of 1.0 mg. estradiol benzoate for 14 days greatly increased serum Ca and liver total crude protein, increased slightly liver total DNAP and increased greatly liver total RNAP and ratio RNAP: DNAP in the liver. The thyroidal treatment reduced estrogen-induced increase of serum Ca and of liver crude protein but did not alter significantly the effects of estrogen on liver DNAP and RNAP.The thyroidal treatment increased kidney weight in both unestrogenized and estrogenized pullets.Estrogen treatment increased kidney weight and the percentage of dry matter in the kidney.The thyroidal treatment did not affect the degree of estrogen-induced hypertrophy of the oviduct.

Enhancement of iron availability by some organic materials

1979 ◽  
Vol 93 (1) ◽  
pp. 115-120 ◽  
Author(s):  
A. A. Parsa ◽  
A. Wallace ◽  
J. P. Martin
Keyword(s):  
Calcareous Soil ◽  
Dry Matter ◽  
Organic Materials ◽  
Iron Availability ◽  
Lawsonia Inermis ◽  
Plant Materials ◽  
Phenolic Substances ◽  
And Control ◽  
Layer Chromatography ◽  
Positive Effect

SUMMARYIn a preliminary laboratory experiment in Iran, not reported here, 5 out of 30 plant materials incorporated into a highly calcareous soil had a positive effect on increasing the DTPA- (diethylenetriaminepentaacetic acid)-extractable Fe and all except one significantly increased the vegetative growth of sorghum. The plant materials included Lawsonia inermis L., Malva silvestris L., Zyzyphus nummularia Wak. and Lavandula carnopifolia L. A glasshouse study was repeated with two California soils pretreated with 0·5% Fe2O3 to determine if these organic materials have practical value in making Fe available to plants. A calcareous, Fe-deficient Hacienda (fine-loamy, mixed, thermic aquic natrargid) and a non-calcareous Yolo (fine-silty, mixed, non-acid, thermic typic xerothents). The previously mentioned organic materials and Laminaria saccharina L. (Lamour) were incorporated into the soils at two rates, 15000 and 20000μg/g, as air dry and in ash form. An adequate supply of major and micronutrients other than Fe was ensured. Other treatments included 5 μg Fe/g as FeSO4, Fe-138 chelate and control. All of the plant materials with the exception of L. carnopifolia significantly increased dry-matter yield and Fe, Zn, Cu and Mn uptake by sorghum in the Hacienda soil. In the Yolo soil the above were not significant. Thin-layer chromatography of the extracts of the plant materials revealed the presence of significant quantities of phenolic substances.

Market exits during the pandemic

2021 ◽  
pp. 113-133
Author(s):  
E. V. Bessonova ◽  
S. M. Myakisheva ◽  
A. N. Tsvetkova
Keyword(s):  
Growth Potential ◽  
Efficiency Enhancement ◽  
High Productivity ◽  
Young Firms ◽  
Lower Productivity ◽  
Fast Development ◽  
Negative Effect ◽  
Positive Effect ◽  
Substantial Rise ◽  
Stimulation Of

The new coronavirus pandemic has triggered an economic crisis different from other crises in the acuteness and non-uniformity of its impact on various sectors of the economy. This paper analyzes how the dynamics of firms entering and exiting the market have changed in this environment and which groups of firms have shown to be the most vulnerable to the negative effect of the crisis. Our analysis shows that the number of newly registered firms dwindled sharply in the period of the toughest restrictions imposed to curtail the infection spread in April — May 2020. The recovery which followed in the subsequent months has failed to compensate for the spring’s slump, which may suggest a “scarring impact” of the crisis. July and October 2020 saw a substantial rise in companies’ exits from the market. The crisis has hurt not only the hardest hit industries but also other areas of economic activity. Liquidations rose most extensively among young firms aged less than three years. Relatively higher productivity firms exited less often than lower productivity companies. This may suggest a “cleansing effect” of the crisis. But with the redundant labor being unable to move to more productive firms, the positive effect of the crisis may be brought to naught. Therefore, for the consequences of the crisis to be remedied, incentives should be provided to new firms’ entries and support for efficient companies, especially for young firms showing growth potential. Stimulation of growth in the number of high-productivity firms should go hand in hand with the creation of conditions for new entities’ fast development, expansion, and efficiency enhancement.

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