Physiological and morphological differences between somatic, in vitro germinated, and normal seedlings of red spruce (Picea rubens Sarg.)

1998 ◽  
Vol 28 (7) ◽  
pp. 1088-1092 ◽  
Author(s):  
Mama Nsangou ◽  
Michael Greenwood

Growth and foliar characteristics of red spruce (Picea rubens Sarg.) seedlings produced from somatic embryos (SS) from cell lines representing three genotypes, zygotic embryos (ZS) germinated in vitro, and normal seed (NS) germinated in a greenhouse were compared after 8 months of growth in the greenhouse. NS and SS were similar in terms of height, diameter, root to shoot ratio, and total plant dry mass, but ZS grew significantly more. The root to shoot ratio of ZS was only one half that of SS and NS. Foliar characteristics such as needle dry mass and specific leaf area were also similar between SS and NS and appeared to be distinctly juvenile, but were the most juvenile in ZS. Net photosynthesis, stomatal conductance, and total chlorophyll content were lowest in the ZS, even though they grew the most. After 2 years of growth in pots outdoors, the stem diameter of ZS was still significantly greater than that of SS or NS, although height growth was no longer significantly different. There was no evidence that SS showed signs of accelerated maturation. The possibility that the unexpectedly greater growth of ZS is due to environmental variation during seed set and early germination that affects subsequent seedling growth and development is discussed.

1998 ◽  
Vol 123 (4) ◽  
pp. 581-585 ◽  
Author(s):  
Takashi Nishizawa ◽  
Kenji Saito

Tomato plants (Lycopersicon esculentum Mill `Ougata-fukuju' and `Korokoro') were grown in a soil or a hydroponic culture to study effects of rooting volume restriction on plant growth and carbohydrate concentrations. In soil culture, leaf lengths decreased linearly as container volume decreased, while plant height did not decrease linearly, irrespective of fruiting. The root to shoot ratio decreased in smaller volume containers, irrespective of fruiting, because dry mass accumulation in the stem and leaves was relatively less inhibited than that in the roots. Total plant dry mass did not differ between fruiting and deblossomed plants, irrespective of container volume. In hydroponic culture, plant height in small containers (37 cm3) was similar to that in large containers (2024 or 4818 cm3). The root to shoot ratio of the plants grown in small containers was lower than that of the plants grown in large containers, mainly due to less inhibition of the dry mass accumulation in the stem than in the leaves. When small containers were almost filled with roots (28 days after transplanting), soluble sugar and starch concentrations in leaves became ≈2-fold higher in the plants grown in small than in those grown in large containers. At the end of experiment (42 days after transplanting), sucrose and starch concentrations in the stem were higher in plants grown in small than in those grown in large containers. However, soluble sugar and starch concentrations in the leaves did not differ between treatments.


HortScience ◽  
1990 ◽  
Vol 25 (9) ◽  
pp. 1074d-1074
Author(s):  
Graham J. Wright ◽  
Irwin E. Smith

Composted pine bark is one of the most important substrates used in the seedling industry today. Previous work suggested the availability of inherent Potassium (K) in the bark. This research confirmed the availability of K and indicated that little or no K is needed for seedling production when pine bark is used as a substrate. Pre-enrichment rates ranged from 0 to 460 g.K.m-3, with a supplemental solution application of 0 to 200 mg.K.l-1. No evidence of K deficiencies or toxicities were detected. Three K sources, KCl, KNO3, and K2SO4 were used in the pre-enrichment of the bark. No differences were noted for top fresh mass, seedling height, root dry mass, root to shoot ratio and percentage moisture. Seedlings grown in treatments without and supplementary K showed tissue contents of 162.5 mg.K.kg-1. This research suggests the possibility of reducing the levels of-K applied to seedlings grown in a composted pine bark substrate.


Castanea ◽  
2019 ◽  
Vol 84 (2) ◽  
pp. 128
Author(s):  
John R. Butnor ◽  
Brittany M. Verrico ◽  
Kurt H. Johnsen ◽  
Christopher A. Maier ◽  
Victor Vankus ◽  
...  

Author(s):  
Er-Meng Gao ◽  
Bongkoch Turathum ◽  
Ling Wang ◽  
Di Zhang ◽  
Yu-Bing Liu ◽  
...  

AbstractThis study evaluated the differences in metabolites between cumulus cells (CCs) and mural granulosa cells (MGCs) from human preovulatory follicles to understand the mechanism of oocyte maturation involving CCs and MGCs. CCs and MGCs were collected from women who were undergoing in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) treatment. The differences in morphology were determined by immunofluorescence. The metabolomics of CCs and MGCs was measured by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) followed by quantitative polymerase chain reaction (qPCR) and western blot analysis to further confirm the genes and proteins involved in oocyte maturation. CCs and MGCs were cultured for 48 h in vitro, and the medium was collected for detection of hormone levels. There were minor morphological differences between CCs and MGCs. LC-MS/MS analysis showed that there were differences in 101 metabolites between CCs and MGCs: 7 metabolites were upregulated in CCs, and 94 metabolites were upregulated in MGCs. The metabolites related to cholesterol transport and estradiol production were enriched in CCs, while metabolites related to antiapoptosis were enriched in MGCs. The expression of genes and proteins involved in cholesterol transport (ABCA1, LDLR, and SCARB1) and estradiol production (SULT2B1 and CYP19A1) was significantly higher in CCs, and the expression of genes and proteins involved in antiapoptosis (CRLS1, LPCAT3, and PLA2G4A) was significantly higher in MGCs. The level of estrogen in CCs was significantly higher than that in MGCs, while the progesterone level showed no significant differences. There are differences between the metabolomes of CCs and MGCs. These differences may be involved in the regulation of oocyte maturation.


Agronomy ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 97
Author(s):  
Mazhar H. Tunio ◽  
Jianmin Gao ◽  
Imran A. Lakhiar ◽  
Kashif A. Solangi ◽  
Waqar A. Qureshi ◽  
...  

The atomized nutrient solution droplet sizes and spraying intervals can impact the chemical properties of the nutrient solution, biomass yield, root-to-shoot ratio and nutrient uptake of aeroponically cultivated plants. In this study, four different nozzles having droplet sizes N1 = 11.24, N2 = 26.35, N3 = 17.38 and N4 = 4.89 µm were selected and misted at three nutrient solution spraying intervals of 30, 45 and 60 min, with a 5 min spraying time. The measured parameters were power of hydrogen (pH) and electrical conductivity (EC) values of the nutrient solution, shoot and root growth, ratio of roots to shoots (fresh and dry), biomass yield and nutrient uptake. The results indicated that the N1 presented significantly lower changes in chemical properties than those of N2, N3 and N4, resulting in stable lateral root growth and increased biomass yield. Also, the root-to-shoot ratio significantly increased with increasing spraying interval using N1 and N4 nozzles. The N1 nozzle also revealed a significant effect on the phosphorous, potassium and magnesium uptake by the plants misted at proposed nutrient solution spraying intervals. However, the ultrasonic nozzle showed a nonsignificant effect on all measured parameters with respect to spraying intervals. In the last, this research experiment validates the applicability of air-assisted nozzle (N1) misting at a 30-min spraying interval and 5 min of spraying time for the cultivation of butter-head lettuce in aeroponic systems.


1994 ◽  
Vol 24 (5) ◽  
pp. 954-959 ◽  
Author(s):  
L.J. Samuelson ◽  
J.R. Seiler

The interactive influences of ambient (374 μL•L−1) or elevated (713 μL•L−1) CO2, low or high soil fertility, well-watered or water-stressed treatment, and rooting volume on gas exchange and growth were examined in red spruce (Picearubens Sarg.) grown from seed through two growing seasons. Leaf gas exchange throughout two growing seasons and growth after two growing seasons in response to elevated CO2 were independent of soil fertility and water-stress treatments, and rooting volume. During the first growing season, no reduction in leaf photosynthesis of seedlings grown in elevated CO2 compared with seedlings grown in ambient CO2 was observed when measured at the same CO2 concentration. During the second growing season, net photosynthesis was up to 21% lower for elevated CO2-grown seedlings than for ambient CO2-grown seedlings when measured at 358 μL•L−1. Thus, photosynthetic acclimation to growth in elevated CO2 occurred gradually and was not a function of root-sink strength or soil-fertility treatment. However, net photosynthesis of seedlings grown and measured at an elevated CO2 concentration was still over 2 times greater than the photosynthesis of seedlings grown and measured at an ambient CO2 concentration. Growth enhancement by CO2 was maintained, since seedlings grown in elevated CO2 were 40% larger in both size and weight after two growing seasons.


1995 ◽  
Vol 74 (5) ◽  
pp. 717-722 ◽  
Author(s):  
Erling S. Nordøy

Mammals are known to utilize wax esters with an efficiency of less than 50%. The purpose of the present study was to examine whether or not minke whales (Balaenoptera acutorostrata), which at times may eat considerable amounts of wax-ester-rich krill, represent an exception to this general pattern. Samples of fresh undigested forestomach, as well as colon, contents were obtained from minke whales (n5) that had been feeding on krill (Thysanoessa inermis) for some time. The samples were analysed for dry mass, energy density, lipid content and the major lipid classes, including wax esters. The concentrations of wax esters were compared with previous estimates of dry-matter disappearance of the same type of prey using anin vitrotechnique, to calculate the dry-matter digestibility of wax esters (DMDwax). Wax esters contributed 21% of the energy and 47% of total lipids in the krill diet. The energy density of gut contents decreased by 50% after their passage from forestomach to the end of the colon. The DMDwaxwas 94·1 (SD 2·8)% (n5). This high DMDwaxand the occurrence of fatty alcohols, one of the products of wax-ester hydrolysis, in faeces show that minke whales are very efficient digesters of wax esters and absorb most of the energy-rich products of this process.


Genetika ◽  
2005 ◽  
Vol 37 (2) ◽  
pp. 165-171 ◽  
Author(s):  
Vladislava Galovic ◽  
Zorana Kotaranin ◽  
Srbislav Dencic

Analyzed in this paper were the in vitro effects of drought stress in 13 genotypes of winter wheat, one genotype of spring wheat, and three Triticale genotypes of different geographic origin. Callus tissue was induced from immature zygotic embryos (10-15 days after pollination) on a modified MS nutrient medium. After two weeks, callus tissue was transplanted onto the same medium enriched with 5% high-molecular polyethylene glycol (PEG 6000), which was used as the stress agent to produce the effect of drought chemically. A control group of calluses was grown on an identical medium but without PEG. After four weeks of growing calluses on these mediums, we assessed callus mass survival ability of the genotypes before the transplantation as well as percentage reduction of callus fresh weight after the transplantation onto the nutrient medium with 5% PEG. Statistically significant differences were found among the genotypes in their response to the induced stress. The best survival ability before the transplantation was found in the genotype Mexicol20 (83%), while the lowest was recorded in Slavija (11.3%). Culture growing under stress conditions significantly reduced callus fresh weight in all of the genotypes. The lowest decrease of the callus mass relative to control was recorded in Rozofskaja (14.4%) and the highest in Miranovska (58.4%), indicating the genotypes' tolerance levels towards drought stress.


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