THE RELATIONSHIP OF TOTAL COPPER 48-H LC50s TO DAPHNIA MAGNA DRY WEIGHT

1993 ◽  
Vol 12 (5) ◽  
pp. 903 ◽  
Author(s):  
James M. Lazorchak ◽  
William T. Waller
Keyword(s):  
Daphnia Magna ◽  
Dry Weight ◽  
Total Copper ◽  
Relationship Of ◽  
The Relationship

Population variation in Sorghum halepense, Johnson grass, at the northern limits of its range

1984 ◽  
Vol 62 (9) ◽  
pp. 1781-1790 ◽  
Author(s):  
S. I. Warwick ◽  
B. K. Thompson ◽  
L. D. Black
Keyword(s):  
New York ◽  
Dry Weight ◽  
Population Variation ◽  
Sorghum Halepense ◽  
Johnson Grass ◽  
Allocation Patterns ◽  
Cultivated Species ◽  
Relationship Of ◽  
The Relationship ◽  
Enzyme Patterns

Thirteen populations of Sorghum halepense, Johnson grass, were sampled from fields in Ontario, Canada, and Ohio and New York, United States. Only four of these populations were reported to overwinter as rhizomes. The morphology, phenology, resource allocation patterns, and growth of seedling and mature plants of the overwintering and the non-overwintering populations were compared. Field-collected specimens from the nonoverwintering populations had wider culms and leaves and larger seeds and inflorescences. Analysis of material grown in a 5-month greenhouse trial indicated similar differences. Greenhouse plants from the nonoverwintering populations were also characterized by greater percent emergence, larger and faster growing seedlings, earlier flowering, larger culms and seeds, greater reproductive dry weight per plant, and about 1/10th the rhizome dry weight of overwintering plants. Differences between populations within a biotype were evident for both biotypes, although there was little within-population variation, except in rhizome production, where certain individuals of some nonoverwintering populations did not produce extended rhizomes. Among the five enzymes which were examined electrophoretically, only one, phosphoglucomutase (PGM), showed variable isozyme patterns. No differences in enzyme patterns were apparent between the overwintering and the nonoverwintering biotypes. The relationship of the nonoverwintering populations to the cultivated species, Sorghum bicolor and S. almum, an introgressant between S. halepense and S. bicolor, is discussed.

scholarly journals Temperature Affects Leaf Unfolding Rate and Flowering of Cyclamen

HortScience ◽  
2001 ◽  
Vol 36 (2) ◽  
pp. 292-294 ◽  
Author(s):  
Meriam Karlsson ◽  
Jeffrey Werner
Keyword(s):  
Dry Weight ◽  
Similar Rate ◽  
Flower Number ◽  
Flower Buds ◽  
Open Flower ◽  
Leaf Unfolding ◽  
Response To Temperature ◽  
Relationship Of ◽  
The Relationship ◽  
Large Flower

The rate of leaf unfolding for Cyclamen persicum Mill. was determined at 8 to 24 °C. Temperature treatments started 9 weeks from seeding and after 8 weeks all plants were moved to 16 °C. The cultivars Miracle Salmon, Miracle Scarlet, and Miracle White produced leaves at a similar rate. The relationship of (leaves/d) = - 0.01727 - 0.02284 * °C + 0.005238 * (°C)2 - 0.000162 * (°C)3 (R2 = 0.99) best described the leaf unfolding rate in response to temperature. The maximum leaf unfolding rate was estimated to 0.329 leaves/day at 19.1 °C. Flower buds (2 mm diameter) developed within 60 days from the start of temperature treatments except at 8 °C. Thirty-five additional days at 16 °C were required for cyclamen initially grown at 8 °C for 8 weeks to produce flower buds. Despite similar conditions during bud development, flowering was delayed 14 to 18 days for plants initially grown at 24 °C compared to those grown at 12 to 20 °C. Plants initially at 8 °C did not flower within 70 days at 16 °C. Leaf and flower numbers at first open flower increased as initial temperature increased from 12 to 24 °C while dry weight and height only increased to 20 °C. No correlation between leaf unfolding and rate of flowering or flower number was detected. Recommendations for 20 °C during early cyclamen growth can be expected to support rapid rates of leaf unfolding and development, and large flower numbers.

scholarly journals Flooding Reduces Gas Exchange and Growth in Snap Bean

HortScience ◽  
1991 ◽  
Vol 26 (4) ◽  
pp. 372-373 ◽  
Author(s):  
Bharat P. Singh ◽  
Kevin A. Tucker ◽  
James D. Sutton ◽  
Harbans L. Bhardwaj
Keyword(s):  
Gas Exchange ◽  
Net Photosynthesis ◽  
Dry Weight ◽  
Quadratic Model ◽  
Snap Bean ◽  
Blue Lake ◽  
Relationship Of ◽  
The Relationship ◽  
Best Fit ◽  
Prior Stress

This study was conducted to determine the effect of various flooding durations on the growth, water relations, and photosynthesis of the snap bean (Phaseolus vulgaris L.). Greenhouse-grown plants of cv. Blue Lake 274 were flooded for 0 (control), 1, 3, 5, or 7 days. Leaf water potential (ψ), stomatal conductance (gs), transpiration (E), and net photosynthesis (Pn) were measured at the completion of the flooding period and after recovery for 7 days. Root, stem, and leaf dry weights were recorded after plants were allowed to recover from the flooding stress for 7 days. The values for ψ, gs, E, and Pn decreased quadratically with the increase in the duration of flooding. The Pn of plants flooded for 1 day was 17% lower than that of the control and it reached near zero in plants flooded for 7 days. The decrease in Pn after 1 day of flooding was not associated with ψ or gs; however, for longer duration of flooding, Pn decline coincided with the decline in gs. A week after the cessation of flooding, the level of recovery in ψ, E, and Pn was linear and that in gs quadratic to the duration of prior stress experienced by the plant. However, after recovering for 7 days, none of the flooded plants regained gas exchange activities at par with the control. The relationship of stem dry weight to duration of flooding was linear, while a quadratic model provided the best fit for the regression of root and leaf dry weight on the number of days of flooding. Overall, even 1 day of flooding reduces photosynthesis in snap bean and causes a decrease in dry weight of the plant. the extent of decrease in both increasing with the duration of flooding.

The Respiratory Physiology of the Marine Nematodes Enoplus Brevis (Bastian) and E. Communis (Bastian)

1973 ◽  
Vol 59 (1) ◽  
pp. 255-266
Author(s):  
H. J. ATKINSON
Keyword(s):  
Oxygen Consumption ◽  
Body Size ◽  
Oxygen Tension ◽  
Dry Weight ◽  
Respiratory Physiology ◽  
Rate Of Oxygen Consumption ◽  
Oxygen Tensions ◽  
The Difference ◽  
Relationship Of ◽  
The Relationship

1. The rate of oxygen consumption of individual males of Enoplus brevis and E. communis was measured at 15 °C and at each of four oxygen tensions, 135, 75, 35, and 12 Torr, after at least 12 h experience of these conditions. 2. It was clearly demonstrated that the level of oxygen consumption of both species was reduced by each lowering of the imposed oxygen tension. 3. In all cases the oxygen consumption of each species fell with increasing body size. On a unit dry-weight basis the oxygen consumption of E. brevis is greater than that of the larger E. communis, but after allowing for the difference of body size the two species have more or less similar oxygen uptakes at all oxygen tensions. 4. In E. brevis oxygen tension influenced the relationship of body size and metabolism, the slope relating oxygen consumption and body weight becomes steeper with decreasing oxygen tension. This effect was not shown by E. communis. 5. Some general factors influencing the availability of oxygen to nematodes are considered.

scholarly journals Potential Role of Laccases in the Relationship of the Maize Late Wilt Causal Agent, Magnaporthiopsis maydis, and Its Host

2020 ◽  
Vol 6 (2) ◽  
pp. 63
Author(s):  
Ofir Degani ◽  
Yuval Goldblat
Keyword(s):  
Potential Role ◽  
Dry Weight ◽  
Maize Cultivars ◽  
Maize Plants ◽  
Relationship Of ◽  
The Relationship ◽  
Host Tissues ◽  
Adult Plants

Late wilt is a vascular disease of maize (Zea mays L.) caused by the soil-borne and seed-borne fungus Magnaporthiopsis maydis. The pathogen penetrates the roots of maize plants at the seedling stage, grows into the xylem vessels, and gradually spreads upwards. From the flowering stage to the kernel ripening, the fungal hyphae and secreted materials block the water supply in susceptible maize cultivars, leading to rapid dehydration and death. Laccase is an enzyme secreted by fungus for diverse purposes. The M. maydis laccase gene was identified in our laboratory, but under what conditions it is expressed and to what functions remain unknown. In the current study, we tested the influence of plant age and tissue source (roots or leaves) on M. maydis laccase secretion. The results show increasing laccase secretion as corn parts (as ground tissue) were added to the minimal medium (MM). Furthermore, roots stimulated laccase secretion more than leaves, and adult plants enhanced laccase secretion more than young plants. This implies the possibility that the richer lignin tissue of adult plants may cause increased secretion of the enzyme. In vitro pathogenicity assay proved the ability of M. maydis to develop inside detached roots of maize, barley, watermelon, and cotton but not peanut. Testing root powder from those plants in MM revealed a negative correlation between M. maydis growth (expressed as biomass) and laccase secretion. For example, while the addition of maize, barley, or cotton root powder led to increasing fungal dry weight, it also resulted in relatively lower laccase activity. Watermelon and peanut root powder led to opposite responses. These findings suggest a pivotal role of laccase in the ability of M. maydis to exploit and grow on different host tissues. The results encourage further examination and a deeper understanding of the laccase role in these interesting host–pathogen interactions.

scholarly journals Correlation between selected parameters of planting material and strawberry yield

2010 ◽  
Vol 22 (1) ◽  
pp. 9-12 ◽  
Author(s):  
Marcin Bartczak ◽  
Jolanta Lisiecka ◽  
Mikołaj Knaflewski
Keyword(s):  
Correlation Coefficients ◽  
Dry Weight ◽  
Fresh Weight ◽  
Planting Material ◽  
Whole Plant ◽  
Different Types ◽  
Positive Correlation Coefficient ◽  
Relationship Of ◽  
The Relationship ◽  
Strawberry Cultivars

Abstract The aim of this study was to determine the effect of fresh and dry weight, as well as the number and length of roots and number of crowns of different types of plants, on the yield of strawberry grown for the spring and autumn harvests. Three different types of frigo strawberry plants (waiting bed plants, plug plants, A+ plants) and two strawberry cultivars (‘Honeoye’ and ‘Elsanta’) were compared in the experiment. The plants were grown in polypropylene bags in an unheated glasshouse in the years 2002-2005. The correlation coefficients were calculated to estimate the relationship of the strawberry plants’ parameters to the yield quantity. An analysis of regression for the plant parameters that most significantly correlated to the strawberry yield was carried out, which determined that the fresh and dry weight of the strawberry plants, crown number, as well as length of roots were positively correlated to the quantity of the strawberry yield. The highest positive correlation coefficient was found for the fresh weight of a whole plant and the lowest one for the number of roots.

MESENTERIC NEUTRAL FAT IN OBESE RATS

1958 ◽  
Vol 36 (1) ◽  
pp. 913-918
Author(s):  
Eldon M. Boyd ◽  
Eleanor M. Crandell
Keyword(s):  
Free Cholesterol ◽  
Dry Weight ◽  
Female Rats ◽  
Albino Rats ◽  
Fat Depots ◽  
Mesenteric Fat ◽  
Obese Rats ◽  
Physiologic Function ◽  
Relationship Of ◽  
The Relationship

The relationship of increasing obesity to storage of neutral fat in the mesentery was investigated in 48 albino rats. Calculated as grams per 100 g nonlipid dry weight, levels of mesenteric neutral fat were positively correlated with levels of mesenteric free cholesterol, phospholipid, and water, the correlation coefficient for water being higher in male than in female rats. These results suggest that storage of neutral fat is an active physiologic function of mesentery. On the other hand, the relative amount of body neutral fat which is stored in the mesentery became less as the animals became more obese. This indicates that in obese rats, some tissue other than mesentery is storing neutral fat at a rate greater than occurs in the mesenteric fat depots.

MESENTERIC NEUTRAL FAT IN OBESE RATS

1958 ◽  
Vol 36 (9) ◽  
pp. 913-918 ◽  
Author(s):  
Eldon M. Boyd ◽  
Eleanor M. Crandell
Keyword(s):  
Free Cholesterol ◽  
Dry Weight ◽  
Female Rats ◽  
Albino Rats ◽  
Fat Depots ◽  
Mesenteric Fat ◽  
Obese Rats ◽  
Physiologic Function ◽  
Relationship Of ◽  
The Relationship

The relationship of increasing obesity to storage of neutral fat in the mesentery was investigated in 48 albino rats. Calculated as grams per 100 g nonlipid dry weight, levels of mesenteric neutral fat were positively correlated with levels of mesenteric free cholesterol, phospholipid, and water, the correlation coefficient for water being higher in male than in female rats. These results suggest that storage of neutral fat is an active physiologic function of mesentery. On the other hand, the relative amount of body neutral fat which is stored in the mesentery became less as the animals became more obese. This indicates that in obese rats, some tissue other than mesentery is storing neutral fat at a rate greater than occurs in the mesenteric fat depots.

scholarly journals Level of inoculum suitable for studies on the relationship of coffee seedlings and Rhizoctonia solani or Myrothecium roridum

1969 ◽  
Vol 83 (3-4) ◽  
pp. 181-188
Author(s):  
Wanda I. Mercado ◽  
Rocío del P. Rodríguez
Keyword(s):  
Rhizoctonia Solani ◽  
Disease Incidence ◽  
Dry Weight ◽  
Seedling Mortality ◽  
Inoculum Level ◽  
Inoculum Concentration ◽  
Myrothecium Roridum ◽  
Relationship Of ◽  
The Relationship ◽  
Coffea Arabica L

Suitable levels of inoculum of Rhizoctonia solani and Myrothecium roridum for the induction of symptoms in coffee (Coffea arabica L.) seedlings were determined in greenhouse tests based on the percentage of seedling mortality and disease incidence. Best inoculum level for R. solani and M. roridum was 15 and 10%, respectively. Myrothecium roridum was more virulent than R. solani, and thus caused higher mortality of coffee seedlings. For both pathogens, as the inoculum concentration increased, the dry weight of plants decreased. A direct positive relation between incidence of the disease and concentration of the inoculum was detected, it was found that R. solani is more persistent than M. roridum in the inoculated soil.

scholarly journals Cabium Browning of Cold-damaged Peach Trees in the Nursery

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 851D-851
Author(s):  
D.E. Deyton ◽  
C.E. Sams ◽  
J.C. Cummins ◽  
D.W. Lockwood
Keyword(s):  
Dry Weight ◽  
Growing Season ◽  
Graft Union ◽  
Trunk Diameter ◽  
Field Temperature ◽  
Nursery Trees ◽  
One Year ◽  
Peach Trees ◽  
Relationship Of ◽  
The Relationship

One-year-old peach trees in nurseries at McMinnville, Tenn., were exposed to –11C on 5 Nov. 1991 before digging. The nursery owners were concerned about the relationship of tree cambium browning to potential tree performance after planting. A color scale [0 = nondamage (white) to 6 = severely damaged (brown)] showing discolored cambium of peach nursery trees was developed to rate damage. Browning was rated at 8 cm above graft union. Five trees each of nine cultivars with chill hour requirements ranging from 175 to 1050 were rated. Cultivars with <500 chill hour requirement had higher ratings. Ten `Harbite' trees from each of six size grades were rated. Trees in grades of 30- to 90-cm height had less cambium browning than trees in grades of 90 to 152 cm height. In Dec. 1992, 1-year-old `Red Globe' trees were exposed to –6 (minimum field temperature), –15, –18, –24, –30, or –35C in a programmable freezer. A subsample of five trees per treatment was rated for browning 1 day after treatment and a second subsample rated in mid February. Trees in a third subsample were grown in a nursery the following summer. Slight browning (rating = 1.6) was evident soon after exposure to –24C; however, severe browning was evident on trees exposed to –30 or –35C. Trees exposed to temperature more than –24C did not differ in height, trunk diameter, or dry weight at the end of the growing season, however trees exposed to –30 or –35C did differ. In a similar experiment, `Juneprince' trees exposed to –18C had slight cambium browning (rating = 1.2) but trees died.

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