Genotypic variation in proanthocyanidin status in the Leucaena genus

2002 ◽  
Vol 138 (2) ◽  
pp. 209-220 ◽  
Author(s):  
S. A. DALZELL ◽  
H. M. SHELTON
Keyword(s):  
Regression Analysis ◽  
Interspecific Hybrids ◽  
Dry Matter ◽  
Genotypic Variation ◽  
Genetic Regulation ◽  
Plant Defence ◽  
Interspecific Variation ◽  
Experimental Conditions ◽  
Commercial Cultivars ◽  
Very High

The proanthocyanidin (PA) status of 116 accessions from the Leucaena genus representing 21 species, 6 subspecies, 3 varieties and 4 interspecific hybrids was evaluated under uniform environmental and experimental conditions at Redland Bay, Queensland, Australia in October 1997. The PA content of lyophilized youngest fully expanded leaves was measured spectrophotometrically by the butanol/HCl assay referenced to L. leucocephala ssp. glabrata standard PA and expressed as L. leucocephala ssp. glabrata PA equivalents (LLPAE). Considerable interspecific variation in PA concentration existed within the genus, ranging from 0–339 g LLPAE/kg dry matter (DM). Taxa including L. confertiflora, L. cuspidata, L. esculenta and L. greggii contained very high (>180 g LLPAE/kg DM) PA concentrations. Similarly, many agronomically superior accessions from L. diversifolia, L. pallida and L. trichandra contained extremely high (up to 250 g LLPAE/kg DM) PA concentrations, although these taxa exhibited wide intraspecific variation in PA content offering the potential to select accessions with lower (120–160 g LLPAE/kg DM) PA content. Commercial cultivars of L. leucocephala ssp. glabrata, known to produce forage of superior quality, contained low amounts of PA (33–39 g LLPAE/kg DM). Artificial interspecific hybrids had PA contents intermediate to those of both parents. Lesser-known taxa, including L. collinsii, L. lanceolata, L. lempirana, L. macrophylla, L. magnifica, L. multicapitula, L. salvadorensis and L. trichodes, contained undetectable to low (0–36 g LLPAE/kg DM) quantities of PA and have potential as parents to breed interspecific hybrids of low PA status and superior forage quality. Extractable PA was the dominant PA component, accounting for 91% of total PA within the genus. Regression analysis of accession ranks from different experiments compared to these results indicated that genetic regulation of Leucaena spp. PA content was consistent (P<0·01) under different edapho-climatic environments. The distribution of PA within the Leucaena genus did not concur with the predictions of various evolutionary and phylogenetic plant defence theories.

scholarly journals Кинетика нарастания ап-конверсионной люминесценции кристалла LiY-=SUB=-0.8-=/SUB=-Yb-=SUB=-0.2-=/SUB=-F-=SUB=-4-=/SUB=- : Tm-=SUP=-3+-=/SUP=- (0.2 at.%) при импульсном возбуждении

2019 ◽  
Vol 61 (5) ◽  
pp. 953
Author(s):  
А.В. Михеев ◽  
Б.Н. Казаков
Keyword(s):  
Regression Analysis ◽  
Energy Transfer ◽  
Rare Earth ◽  
Laser Diode ◽  
Rare Earth Ions ◽  
Experimental Conditions ◽  
Pulsed Excitation ◽  
Transfer Processes ◽  
Dipole Interactions ◽  
Kinetics Of

AbstractThe regression analysis of the rise kinetics of up-conversion luminescence of the LiY_0.8Yb_0.2F_4:Tm^3+ (0.2 at %) crystal is performed. The kinetics curve is obtained with rectangular pulsed excitation by radiation from a laser diode (IR LD) with a wavelength of λ_ p = 933 nm. The most important—in these experimental conditions—mechanisms of the energy transfer from Yb^3+ ions to Tm^3+ ions are established, which are responsible for the transitions between the ground ^3 H _6 and excited ^3 F _4, ^3 H _4, ^1 G _4, ^1 D _2, and ^1 I _6 terms of the Tm^3+ ions. The durations of the relevant energy transfer processes are determined. It is shown that the energy transfer between rare earth ions in the LiY_0.8Yb_0.2F_4:Tm^3+ (0.2 at %) crystal occurs through the dipole–dipole interactions.

Resistance to Aryloxyphenoxypropionate and Cyclohexanedione Herbicides in Wild Oat (Avena fatua)

Weed Science ◽  
1993 ◽  
Vol 41 (2) ◽  
pp. 232-238 ◽  
Author(s):  
Ian M. Heap ◽  
Bruce G. Murray ◽  
Heather A. Loeppky ◽  
Ian N. Morrison
Keyword(s):  
Dry Matter ◽  
Cross Resistance ◽  
Western Canada ◽  
Wild Oat ◽  
Recommended Dosage ◽  
Susceptible Population ◽  
South Central ◽  
Repeated Applications ◽  
High Level ◽  
Very High

Resistance to aryloxyphenoxypropionate and cyclohexanedione herbicides was identified in four wild oat populations from western Canada. Populations UM1, UM2, and UM3 originated from northwestern Manitoba and UM33 from south-central Saskatchewan. Field histories indicated that these populations were exposed to repeated applications of diclofop-methyl and sethoxydim over the previous 10 yr. The populations differed in their levels and patterns of cross-resistance to these and five other acetyl-CoA carboxylase inhibitors (ACCase inhibitors). UM1, UM2, and UM3 were resistant to diclofop-methyl, fenoxaprop-p-ethyl, and sethoxydim. In contrast, UM33 was resistant to the aryloxyphenoxy propionate herbicides but not to sethoxydim. The dose of sethoxydim required to reduce growth of UM1 by 50% was 150 times greater than for a susceptible population (UM5) or UM33 based on shoot dry matter reductions 21 d after treatment. This population differed from UM2 and UM3 that had R/S ratios of less than 10. In the field UM1 also exhibited a very high level of resistance to sethoxydim. In contrast to susceptible plants that were killed at the recommended dosage, shoot dry matter of resistant plants treated at eight times the recommended dosage was reduced by only 27%. In growth chamber experiments none of the four populations was cross-resistant to herbicides from five different chemical families.

A Holistic Approach to Characterize Mud Loss Using Dynamic Mud Filtration Data

2019 ◽  
Vol 141 (7) ◽  
Author(s):  
Chinedum Peter Ezeakacha ◽  
Saeed Salehi
Keyword(s):  
Regression Analysis ◽  
Field Application ◽  
Operating Conditions ◽  
Mitigation Strategies ◽  
Drilling Mud ◽  
Experimental Conditions ◽  
Lost Circulation ◽  
Rotary Speed ◽  
Mud Filtration ◽  
Mud Loss

Drilling mud loss in highly porous media and fractured formations has been one of the industry's focuses in the past decades. Wellbore dynamics and lithology complexities continue to push for more research into accurate quantification and mitigation strategies for lost circulation and mud filtration. Conventional methods of characterizing mud loss with filtration data for field application can be time-consuming, particularly because of the interaction between several factors that impact mud loss and filtration. This paper presents a holistic engineering approach for characterizing lost circulation using pore-scale dynamic water-based mud (WBM) filtration data. The approaches used in this study include: factorial design of experiment (DoE), hypothesis testing, analysis of variance (ANOVA), and multiple regression analysis. The results show that an increase in temperature and rotary speed can increase dynamic mud filtration significantly. An increase in lost circulation material (LCM) concentration showed a significant decrease dynamic mud filtration. A combination of LCM concentration and rotary speed showed a significant decrease in dynamic mud filtration, while a combination of LCM concentration and temperature revealed a significant increase in dynamic mud filtration. Rotary speed and temperature combination showed an increase in dynamic mud filtration. The combined effect of these three factors was not significant in increasing or decreasing dynamic mud filtration. For the experimental conditions in this study, the regression analysis for one of the rocks showed that dynamic mud filtration can be predicted from changes in LCM concentration and rotary speed. The results and approach from this study can provide reliable information for drilling fluids design and selecting operating conditions for field application.

Genotypic Variation in Carbon Isotope Discrimination and Transpiration Efficiency in Wheat. Leaf Gas Exchange and Whole Plant Studies

1990 ◽  
Vol 17 (1) ◽  
pp. 9 ◽  
Author(s):  
AG Condon ◽  
GD Farquhar ◽  
RA Richards
Keyword(s):  
Boundary Layer ◽  
Water Loss ◽  
Dry Matter ◽  
Carbon Isotope Discrimination ◽  
Genotypic Variation ◽  
Transpiration Efficiency ◽  
Layer Resistance ◽  
Boundary Layer Resistance ◽  
The Relationship ◽  
Canopy Water

The relationship between carbon isotope discrimination, Δ, measured in plant dry matter and the ratio of intercellular to atmospheric partial pressures of CO2, pi/pa, in leaves was examined in two glasshouse experiments using 14 wheat genotypes selected on the basis of variation in Δ of dry matter. Genotypic variation in Δ was similar in both experiments, with an average range of 1.8 x 10-3. Variation in pi/pa was significant but the range in pi/pa was relatively small, averaging 0.075. In both experiments, Δ measured in dry matter and pi/pa measured in flag leaves were positively correlated. Variation among genotypes in pi/pa was attributed, approximately equally, to variation in leaf conductance and in photosynthetic capacity. The relationship between plant transpiration efficiency, W* (the amount of above-ground dry matter produced per unit water transpired) and � was also examined. There was a negative correlation between W * and Δ; under well watered conditions and under gradually increasing terminal water stress. The relationship between W* of stressed plants and Δ measured in well watered plants was also negative. These results indicate that genotypic variation in Δ measured in dry matter should provide a reasonable measure of genotypic variation in long-term mean leaf pi/pa in wheat. Further, selection for improved plant transpiration efficiency in wheat under both well watered and terminally water- stressed conditions should be possible based on Δ measured in well watered plants. The extent to which such selection will be effective in improving transpiration efficiency at the field canopy level may depend on the influence of boundary layer resistance on transpirationsal water loss. Under well watered conditions and at full canopy closure, the influence of boundary layer resistance on canopy water loss may be relatively large and stomatal control of water loss may be limited. Under water stress, stomatal control of canopy water loss will be greater.

Growth and Seed Return of Auxin-Type Herbicide Resistant Wild Mustard (Brassica kaber) in Wheat

Weed Science ◽  
1996 ◽  
Vol 44 (4) ◽  
pp. 871-878 ◽  
Author(s):  
Daniel J. Debreuil ◽  
Lyle F. Friesen ◽  
Ian N. Morrison
Keyword(s):  
Selection Pressure ◽  
Dry Matter ◽  
Dry Matter Accumulation ◽  
Recommended Dosage ◽  
Herbicide Resistant ◽  
Wild Mustard ◽  
Phenoxy Herbicide ◽  
High Selection ◽  
Brassica Kaber ◽  
Very High

The growth and seed return of auxin herbicide resistant (R) wild mustard was compared to that of a susceptible (S) biotype in wheat in the field. In the absence of herbicide, the S biotype accumulated shoot dry matter more quickly than the R biotype throughout most of the growing season. However, in only one of the two years did the S biotype set substantially more seed than the R biotype (3120 versus 2520 seeds plant−1). The recommended dosage of 2,4-D for wild mustard control (420 g ai ha−1) killed all S plants in both years of the study, and severely inhibited growth and seed return of R plants. Shoot dry matter accumulation and seed return of treated R plants were reduced 75 to 90% compared to the untreated control. However, at a density of 20 plants m−2R seed return was still very high; 9000 and 5700 seeds m−2in 1992 and 1993, respectively. The recommended dosage of dicamba (300 g ha−1) did not inhibit the growth and seed return of either S or R wild mustard to the same extent as 2,4-D. Dicamba at 300 g ha−1reduced S shoot dry matter and seed return 80 to 90%, while R shoot dry matter and seed return was reduced 60 to 65%. The results of this study indicate a very high selection pressure for R wild mustard at recommended dosages of 2,4-D. Despite a high selection pressure, and considering the long history of phenoxy herbicide usage on the Prairies, the relatively rare occurrence of phenoxy herbicide resistant weeds implies that the frequency of resistant individuals is very low. From a mathematical model it was determined that the frequency of R wild mustard in an unselected population may be in the order of 10−30.

ON BODY FAT AND BODY WATER IN RATS

1955 ◽  
Vol 33 (1) ◽  
pp. 970-979 ◽  
Author(s):  
Louis-Marie Babineau ◽  
Edouard Pagé
Keyword(s):  
Adipose Tissue ◽  
Body Fat ◽  
Dry Matter ◽  
The Body ◽  
Energy Reserves ◽  
Experimental Conditions ◽  
Fat Depots ◽  
Excess Water ◽  
Fat Stores ◽  
Free Body

Under our experimental conditions, water represented 72% of the fat-free body mass. This constant was found to be completely independent of the magnitude of the fat depots. Consideration of the composition of various samples of adipose tissue suggests that the water to fat-free dry matter ratio is the same as in the body as a whole or that any "excess" water contributed by adipose tissue is so small in absolute amounts as to leave the global ratio essentially undisturbed. Rats exposed to cold had to draw on their fat stores during the first month of exposure but later replenished their energy reserves. The water to fat-free dry matter ratio was not affected.

scholarly journals Genotypic Variation in Biomass Produced Is Linked to Differences in Radiation Acquisition in Mungbean

Proceedings ◽  
2019 ◽  
Vol 36 (1) ◽  
pp. 21
Author(s):  
Geetika ◽  
Rachaputi ◽  
Collins ◽  
Singh ◽  
Wenham ◽  
...  
Keyword(s):  
Leaf Area ◽  
Dry Matter ◽  
Genotypic Variation ◽  
Total Biomass ◽  
Potential Productivity ◽  
Area Index ◽  
Canopy Density ◽  
Significant Difference ◽  
Plant Densities ◽  
Rotation Crop

Mungbean has become an important cash and legume rotation crop in the Australian Northern Grains region. Thus, it is necessary to narrow the gap between potential productivity and actual production by understanding the crop physiological attributes contributing to the acquisition of radiation, and it’s conversion into total biomass. A field experiment was conducted at Gatton, during 2018-19 summer season, growing two commercial varieties of mungbean; Jade-AU and Satin II under irrigated conditions. The varieties were planted at 0.5m and 1.0m row spacing and different plant densities. Weekly biomass cuts were taken from a square meter and separated into its components. The area of a green leaf sub-sample was used to compute the leaf area of the canopy. Weekly Ceptometer measurements were taken above and below the canopy at noon on clear, sunny days to obtain a measure of Fraction of radiation interception (Fi). Total shoot dry matter (TDM), pod dry mater (PDM) and leaf area index (LAI) was investigated. There was a significant effect of canopy density on Fi. There was no significant difference in total dry matter between the two varieties, however, there was a highly significant effect of canopy density on TDM. . A highly significant variation in LAI amongst the two varieties and across canopy densities, with Satin II having a higher mean LAI compared to Jade-AU. There was significant effect of canopy density on PDM. Our data indicate variation in dry matter production across canopy densities and there is a need to examine varietal differences in radiation use efficiency which may provide better understanding of hot the captured radiation is utilized in biomass production in mungbean.

Statistical research on the fate of dietary mineral elements in dry and lactating cows IV. Chloride

1969 ◽  
Vol 73 (2) ◽  
pp. 223-229 ◽  
Author(s):  
R. Paquay ◽  
F. Lomba ◽  
A. Lousse ◽  
V. Bienfet
Keyword(s):  
Milk Production ◽  
Dry Matter ◽  
Mineral Elements ◽  
Statistical Research ◽  
Lactating Cows ◽  
Chloride Excretion ◽  
Daily Milk Production ◽  
Very High ◽  
Matter Energy ◽  
Daily Milk

SUMMARYStatistical analyses were carried out on the data obtained under very strict conditions in metabolism stalls with 41 different rations fed to 127 adult non-pregnant dry cows, and with 14 other different rations fed to 35 adult non-pregnant lactating cows that had calved 2–6 months earlier and whose daily milk production ranged from 11 to 20 kg.The authors have calculated and studied the correlations between faecal and urinary losses of chloride, chloride excretion with the milk, digestible chloride and chloride balance and many other nutritive factors which were analysed for each of the 55 above mentioned experimental diets.The results show that the digestion and utilization of chloride is not influenced by the amount of ingested chloride at the time of the trial. The digestion is generally very high, negatively correlated with dry matter, energy, and pentosans intakes, and positively with nitrogen and potassium intakes. But the most important factor in the fate of dietary chloride seems to be the necessity for the cow to eliminate most of the time high amounts of potassium in the urines.

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