Temperature germination

Table 6.3. Effect of Impact Damage and Germination Temperature on Germination Percentages and Total Seedling Dry Weight Yield of Soybeans...

Damage, Germination Temperature Germination, % Total Seedling Dry Weight Yield, g... 

Table 4.4. Effect of germination temperature on subsequent growth of pea plants...

The estabhshment of safe thermal processes for preserving food in hermetically sealed containers depends on the slowest heating volume of the container. Heat-treated foods are called commercially sterile. Small numbers of viable, very heat-resistant thermophylic spores may be present even after heat treatment. Thermophylic spores do not germinate at normal storage temperatures. 

Under adverse conditions, certain microorganisms produce spores that germinate upon return to a favorable environment. Spores are a particularly stable form or state of bacteria that may survive diyness and temperature extremes. Some microorganisms form spores at a stage in their normal life cycle. 

Extractions and Chemical Analyses of Amaranthus palmerl S. Wats (Amaranthaceae). The plant material for the chemical studies was supplied by Dr. R. M. Menges, USDA, Weslaco, TX. The air-dried aerial parts (518 g) were extracted at ambient temperature with petroleum ether (PE), dichloromethane (CI Clj) and methanol (MeOH) and the solvents were evaporated In vacuo providing 4.5 g, 4.7 g and 12.lg crude extracts, respectively. Samples of the crude extracts were tested by Dr. J. M. Bradow for germination regulation activity and the biological data are described in her paper. 

Carolina in 1981. Each sample (1.4 ml of methanolic sample) was placed into a 3-cm petri dish and the solvent evaporated under a laminar flow hood at room temperature. Seventy seeds (0.035 g) were then placed into the petri dishes and 1.4 ml of sterilized (0.2 pm-filter) 15 mM Mes [2-(N-morpholino)ethanesulfonic acid Sigma Chemical Co.] buffer adjusted to pH 5.5 was added. The dishes were kept in the dark at 25°C2for 84 hr, exposed to 12-hr fluorescent light (250 p einsteins/m /sec), and then placed back in the dark for an additional 4 days (17). Percent germination, root and hypocotyl lengths were then determined. 

Five-g samples of wheat plant material were soaked in 150 ml of water for 10 hr at room temperature. The mixture was filtered and the filtrate used to germinate pitted morningglory (Ipomoea lacunosa L.) and ragweed (Ambrosia artemisiifolia L.) seed. The effect of the extract on germination was tested in the presence and absence of light. 

Procedure Pollen develops on the nutrition medium, forming pollen tube (Fig. 3). The nutrient medium for pollen was 10% sucrose solution and tested compounds were also dissolved in 10% sucrose. The pollen develops till the formation of pollen tube that lasts from 2-3 h (fresh collected and one week stored pollen) to 24 h (stored > 1 week, but < 1.5-2 months). All experiments were done at room temperature 20-22 °C. The growth occurred in the solution studied (0.05 ml = 1 drop) on the slides (object glasses) put on wet paper in Petri dishes. Five ml of water was added to the bottom of every dish and 4-5 dishes with the slides were used per treatment. Using light microscope, we determined the microspores germination (%) 2-24 h after moistening. The number of developed pollen tubes was counted. 

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