scholarly journals Priming with Salt Solutions Improves Germination of Pansy Seed at High Temperatures

HortScience ◽  
1997 ◽  
Vol 32 (2) ◽  
pp. 248-250 ◽  
Author(s):  
BeYoung-Han Yoon ◽  
Harvey J. Lang ◽  
B. Greg Cobb

Priming regimes were evaluated on pansy seeds (Viola ×wittrockiana Gam. `Crystal Bowl Sky Blue') in high-temperature germination tests. Priming regimes evaluated included CaCl2, MgCl2, K2HPO4, Na2HPO4, NaCl, KCl, KNO3, Na2SO4, and polyethylene glycol 15,000 (PEG15,000) at –1.0 and –2.0 MPa, for 3, 6, or 9 d at 23 °C. Primed and nonprimed control seeds were then germinated at 25, 30, or 35 °C. Total percent germination of nonprimed control seeds was significantly less at 35 °C than at 25 °C. Seeds primed with CaCl2 at –1.0 MPa for 3 d at 23 °C had significantly higher germination at 35 °C than all other priming regimes tested, including aerated PEG8000 at –1.0 MPa for 7 d at 15 °C. Seed respiration, measured by O2 uptake, during germination of seeds primed with CaCl2 was higher than for control seeds or those primed with PEG8000. Priming pansy seed with CaCl2 at –1.0 MPa for 3 d at 23 °C was effective in increasing seedling emergence and for reducing the time of emergence in summer greenhouse studies.

HortScience ◽  
1994 ◽  
Vol 29 (5) ◽  
pp. 558e-558
Author(s):  
Beyoung-han Yoon ◽  
Harvey J. Lane ◽  
B. Greg Cobb

Pansy (Viola × wiffrockiana cv. Majestic Giant Blue Shades and Crystal Bowl Sky Blue) seeds were primed in various salt sololions at -1.0 MPa for 3, 6 or 9 days at 23C to determine if priming could overcome thermoinhihition at high temperatures (30C and above). Salt solutions tested were KNO3, KCl, NaCl, MgCl2, Na2SO4, Na2HPO4, K2HPO4 and CaCl2, with polyethylene glycol (PEG) serving as a comparison non-salt solution. Total percent germination (G) of non-primed seeds decreased significantly for both cultivars as germination temperature increased from 25C to 35C. Total seed germination and time to 50% germination (TS,) varied widely among the different priming solutions, with all solutions decreasing Tso as compared to non-primed seeds. Seeds primed with PEG for 6 and 9 days, however, germinated during the priming process and were not further examined. Priming did not significantly improve total percent germination versus non-primed seed at 25C. Seeds that had the best G and T50 at temperatures at or above 30C were those primed for 3 days with CaCl2 (for `Crystal Bowl' there was a 40% increase in G at 35C), and MgCl2 (for `Majestic Giant' there was a 15% increase in G at 35C).


Weed Science ◽  
1980 ◽  
Vol 28 (2) ◽  
pp. 194-196 ◽  
Author(s):  
R. C. Shearman ◽  
E. J. Kinbacher ◽  
K. A. Reierson

Spring establishment of tall fescue (Festuca arundinaceaSchreb. ‘Kentucky 31’) is preferred over fall for turfs in Nebraska. Siduron [1-(2-methylcyclohexyl)-3-phenylurea] is commonly used for weed control in spring-seeded tall fescue. Siduron application rates of 6.8, 13.6, 27.2, and 40.8 kg/ha were compared with an untreated control in this study. All siduron applications reduced stand development. The 6.8 kg/ha rate nearly doubled the number of days for seedling emergence. Abnormal seedlings increased with increasing application rates and percent germination decreased with increasing rates. Tiller number declined at rates of 13.6 kg/ha and above. Plants treated with 6.8 kg/ha were 1.3 cm shorter than those growing in the untreated control. Plant and root dry matter production decreased with increasing application rates. Root weight was reduced more than plant weight. Degree of wilting and drought injury increased at 13.6 kg/ha. Water use declined with increased siduron application rates. The amount of water lost before wilting occurred also declined as siduron application rates increased. High temperature injury on seedlings was reduced with increasing rates of siduron. Reduction in high temperature injury was significantly correlated (r = 0.98) to reduced plant tissue moisture.


HortScience ◽  
1992 ◽  
Vol 27 (10) ◽  
pp. 1077-1079 ◽  
Author(s):  
Carlos A. Parera ◽  
Daniel J. Cantliffe

`Verina' leek (AIlium porrum L.) seed germination is normally reduced at temperatures > 25C. Leek seeds were primed in aerated solutions (1.5 MPa, 10 days at 15C) of d-mannitol (mannitol), polyethylene glycol-8000 (PEG), KNO, and a nonaerated solution of PEG-8000 (PEG). At high temperatures mannitol, PEG, and PEG significantly enhanced germination percentage relative to KNO, or the control. At constant 30C, the mannitol, PEG, and PEG treatments increased final germination almost 10 times and the coefficient of velocity (COV) was improved compared to KNO, and the control. 10 growth chambers with alternating day/night temperatures (38 to 28C or 32 to 22C, 10 to 14 hours, respectively), primed seeds had significantly higher emergence and a larger COV than the control. In a greenhouse study under good conditions for germination, total emergence of primed and nonprimed seeds was similar; however, mannitol, PEG, and PEG led to a significantly higher COV than the control or KNO, treatments. These controlled-environment results demonstrate that priming leek seeds via mannitol, PEG, and PEG may promote early emergence at high temperature and improve stand uniformity for container transplant production.


2008 ◽  
Vol 18 (3) ◽  
pp. 433-435 ◽  
Author(s):  
Ken Takahata ◽  
Yoko Mine ◽  
Atsukiyo Karimata ◽  
Hiroyuki Miura

A study was conducted to improve the seedling emergence rate of lettuce (Lactuca sativa) seeds at high temperatures using a convenient postsown priming method. Seeding mixtures adjusted to 35%, 45%, or 55% moisture content were sown with lettuce ‘Patriot’ in cell trays. Postsown priming was performed at 20 °C for 1 day and at 30 °C for 3 or 5 days. After the treatment, trays were moved to an emergence room kept at 32.5 °C, a temperature assumed to be typical of non-air-conditioned rooms in nurseries. Emergence of nonprimed controls was 9% to 16% after 2 days in the emergence room and was 59% to 75% on day 6. In contrast, seedling emergences on day 2 were 95%, 76%, and 78% to 79% in 55% moisture at 20 °C for 1 day, 55% moisture at 30 °C for 3 days, and 45% to 55% moisture at 30 °C for 5 days, respectively. Therefore, the treatment with 55% moisture at 20 °C for 1 day appeared most effective; however, post-sown priming with 55% moisture at 30 °C for 3 days or 45% to 55% moisture at 30 °C for 5 days may be more practical due to lower temperature-control costs.


2003 ◽  
Vol 762 ◽  
Author(s):  
A. Gordijn ◽  
J.K. Rath ◽  
R.E.I. Schropp

AbstractDue to the high temperatures used for high deposition rate microcrystalline (μc-Si:H) and polycrystalline silicon, there is a need for compact and temperature-stable doped layers. In this study we report on films grown by the layer-by-layer method (LbL) using VHF PECVD. Growth of an amorphous silicon layer is alternated by a hydrogen plasma treatment. In LbL, the surface reactions are separated time-wise from the nucleation in the bulk. We observed that it is possible to incorporate dopant atoms in the layer, without disturbing the nucleation. Even at high substrate temperatures (up to 400°C) doped layers can be made microcrystalline. At these temperatures, in the continuous wave case, crystallinity is hindered, which is generally attributed to the out-diffusion of hydrogen from the surface and the presence of impurities (dopants).We observe that the parameter window for the treatment time for p-layers is smaller compared to n-layers. Moreover we observe that for high temperatures, the nucleation of p-layers is more adversely affected than for n-layers. Thin, doped layers have been structurally, optically and electrically characterized. The best n-layer made at 400°C, with a thickness of only 31 nm, had an activation energy of 0.056 eV and a dark conductivity of 2.7 S/cm, while the best p-layer made at 350°C, with a thickness of 29 nm, had an activation energy of 0.11 V and a dark conductivity of 0.1 S/cm. The suitability of these high temperature n-layers has been demonstrated in an n-i-p microcrystalline silicon solar cell with an unoptimized μc-Si:H i-layer deposited at 250°C and without buffer. The Voc of the cell is 0.48 V and the fill factor is 70 %.


Alloy Digest ◽  
1995 ◽  
Vol 44 (3) ◽  

Abstract NICROFER 5520 Co is a nickel-chromium-cobalt-molybdenum alloy with excellent strength and creep properties up to high temperatures. Due to its balanced chemical composition the alloy shows outstanding resistance to high temperature corrosion in the form of oxidation and carburization. This datasheet provides information on composition, physical properties, elasticity, and tensile properties. It also includes information on high temperature performance as well as forming, heat treating, machining, and joining. Filing Code: Ni-480. Producer or source: VDM Technologies Corporation.


Alloy Digest ◽  
1994 ◽  
Vol 43 (7) ◽  

Abstract Carlson Alloy C601 is characterized by high tensile, yield and creep-rupture strengths for high temperature service. The alloy is not embrittled by extended exposure to high temperatures and has excellent resistance to stress-corrosion cracking, to carburizing, nitriding and sulfur containing environments. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as creep. It also includes information on forming, heat treating, machining, and joining. Filing Code: Ni-458. Producer or source: G.O. Carlson Inc.


Alloy Digest ◽  
2005 ◽  
Vol 54 (11) ◽  

Abstract Incotherm TD is a thermocouple-sheathing alloy with elements of silicon and rare earths to enhance oxidation resistance at high temperatures. This datasheet provides information on composition, physical properties, and tensile properties as well as deformation. It also includes information on high temperature performance and corrosion resistance as well as forming. Filing Code: Ni-628. Producer or source: Special Metals Corporation.


Alloy Digest ◽  
1954 ◽  
Vol 3 (12) ◽  

Abstract HASTELLOY Alloy X is a nickel-chromium-iron-molybdenum alloy recommended for high-temperature applications. It has outstanding oxidation resistance at high temperatures under most operating conditions, and good high-temperature strength. This datasheet provides information on composition, physical properties, and tensile properties as well as creep. It also includes information on forming, heat treating, and machining. Filing Code: Ni-14. Producer or source: Haynes Stellite Company.


Alloy Digest ◽  
2011 ◽  
Vol 60 (11) ◽  

Abstract Kubota Alloy HT is an iron-chromium-nickel alloy that has both strength and oxidation resistance at high temperatures. This datasheet provides information on composition, physical properties, and tensile properties as well as creep. It also includes information on high temperature performance as well as casting and joining. Filing Code: SS-1108. Producer or source: Kubota Metal Corporation, Fahramet Division.


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