Dry matter accumulation into zygotic seed; a model and its application to artificial seeds

1994 ◽  
Vol 4 (2) ◽  
pp. 89-96 ◽  
Author(s):  
Yvon Le Deunff ◽  
Jacques Loiseau
Keyword(s):  
Water Content ◽  
Dry Matter ◽  
Zygotic Embryo ◽  
Dry Weight ◽  
Cell Number ◽  
Dry Matter Accumulation ◽  
Weed Species ◽  
Elementary Model ◽  
Pea Seed

AbstractPea seed development on the mother plant consists of three phases, all limited by water concentration (WC). The first (P1) or embryogenesis sensu stricto takes place at constant WC (stable at 80%). During the phase P2, cotyledon filling or maturation, WC decreases linearly from 80 to 55% (physiological desiccation) but the water content stays constant while the dry weight increases until it stops abruptly (at 55% WC), at this time, the seed has almost reached its final dry weight, its maturity mass or physiological maturity. The third phase, P3, consists of a fast desiccation which leads to a WC of 18–14%, where the seed is mature and ready to harvest. Similar events occur in other grain legumes, in cereals where mass maturity is attained at a lower WC (close to 40%) and in other species including crop or weed species. An elementary model of pea seed dry-matter accumulation, based on the constancy of water content (P1) and the linear decrease of WC from 80 to 55% (P2), allows us to define a coefficient α linked to WC and to calculate dry matter changes versus α. This model, taking account of WC in other species, can be generalized easily. Maturation of the somatic embryo, occurring under conditions very close to those present in vivo around the zygotic embryo, follows a pattern of decrease of WC similar to that of the zygotic embryo. We expect that if cell number is similar in the somatic and the zygotic embryo, synseeds will be ready for trade in the near future since control of all the processes that lead to zygotic-like embryoids is now available.

scholarly journals Field Pea Seed Residue: a Potential Alternative Weed Control Agent

Weed Science ◽  
2010 ◽  
Vol 58 (4) ◽  
pp. 433-441 ◽  
Author(s):  
Susan M. Marles ◽  
Thomas D. Warkentin ◽  
Frederick A. Holm
Keyword(s):  
Weed Control ◽  
Dry Matter ◽  
Growth Suppression ◽  
Field Pea ◽  
Test Plant ◽  
Dry Matter Accumulation ◽  
Weed Species ◽  
Test Species ◽  
Soil P ◽  
Pea Seed

Field pea seed from bin cleaning operations stored overwinter on nearby cropland was observed to correlate with weed and crop growth suppression for up to three subsequent years. To explore the phenomenon more explicitly, plant growth suppression trials were undertaken with soil sampled 18 mo apart from two locations that had contained field pea seed residues. Test plant species grown in the residue-affected and nearby residue-free soils were compared in greenhouse experiments. Germination was either fully inhibited or emergence was delayed by more than one week. Dry matter accumulation of test species grown in residue-affected soil was significantly reduced compared to dry matter of these test species grown in residue-free soil (P < 0.0001). Canola and field pea were inhibited more than wheat and green foxtail over both years. Greenhouse trials also revealed that germination of wild oat was inhibited in the residue-affected soils, although wheat and grassy weeds were less suppressed than dicots overall. Significant reductions of weed species diversity and abundance were correlated to residue-affected soils (P < 0.0001) when compared to residue-free soils using multi-response permutations procedures. Germination of wheat and canola seed was inhibited, using aqueous extracts of weathered pea seeds or extracts of the residue-affected soil in bioassays in sterile media. An allelopathic response was proposed to explain the above results, indicating a need for further research on this system. Weed management strategies could be developed with field pea seed residues to provide innovative weed control techniques.

Effects of Water Deficit on Endosperm Starch Granules and on Grain Physiology of Wheat and Barley.

1982 ◽  
Vol 9 (4) ◽  
pp. 423 ◽  
Author(s):  
A Brooks ◽  
CF Jenner ◽  
D Aspinall
Keyword(s):  
Water Potential ◽  
Water Deficit ◽  
Dry Matter ◽  
Amino Acid Content ◽  
Dry Weight ◽  
Cell Number ◽  
Dry Matter Accumulation ◽  
Starch Granules ◽  
Barley Grains ◽  
Endosperm Starch

Wheat (cv. Sun 9E) and barley (cv. Clipper) plants were subjected to water deficit after anthesis. In both species grain dry matter accumulation was initially unaffected by water deficit but terminated earlier in stressed plants than in controls. Water deficit did not affect endosperm cell number. In water stressed wheat plants the number of B-type starch granules per endosperm and the size of the largest A-type granules were significantly less than in control plants but A-type granule number was unaffected. Water potentials of wheat flag leaves and bracts were reduced by water deficit but this treatment did not affect grain water potential or osmotic potential during the first 29 days after anthesis. During these 29 days, neither grain nor bract water potential of barley was affected by stress and the water potential of bracts was relatively low even in control plants. Maturing grains eventually lost water and endosperm volume declined. This water loss occurred earlier in stressed plants. Stress significantly reduced the amount of sucrose per wheat grain but not the amount of sucrose per unit of grain dry matter or water content. In barley grains, stress did not reduce the relative or absolute sucrose contents. It was considered unlikely that the earlier cessation of grain growth on stressed plants was caused by insufficient assimilate. Although protein as a proportion of grain dry weight was higher in stressed plants than in controls, protein and amino acid content per grain were unaffected by water deficit.

Influence of Water Deficits on the Water Relations Characteristics and Productivity of Wild and Cultivated Sunflowers

1983 ◽  
Vol 10 (2) ◽  
pp. 195 ◽  
Author(s):  
MA Sobrado ◽  
NC Turner
Keyword(s):  
Water Stress ◽  
Water Content ◽  
Water Relations ◽  
Dry Matter ◽  
Weight Ratio ◽  
Dry Weight ◽  
Dry Matter Accumulation ◽  
Water Deficits ◽  
Influence Of Water ◽  
In The Wild

The effects of water deficits on the water relations characteristics and yield of two cultivated Helianthus annuus L. lines, Hysun 31 and Seneca, and two wild Helianthus species, H. nuttallii and H. petiolaris, were compared. The study was conducted on frequently irrigated and unirrigated plants growing in the field during the summer. Predawn measurements of leaf water potential and relative water content showed that, in the uninigated plants, water deficits increased in all species during the first month after sowing (period I), were relieved by rain in the second month (period II), and then increased progressively in the final month (period III). The osmotic potential at full turgor of unirrigated plants, estimated by pressure-volume curves, decreased by 0.12-0.22 MPa during periods I and III in the cultivated sunflowers, but did not decrease significantly in the wild sunflowers. Except in the irrigated Hysun 31 and Seneca during period I, the apoplastic water content was about 20% in all species and treatments. During period I, the turgid weight: dry weight ratio decreased significantly with water stress, particularly in the cultivated sunflowers; the changes were less marked in the wild sunflowers and during period III. Additionally, the turgid weight: dry weight ratio in the imgated cultivated sunflowers decreased throughout the season. The volumetric modulus of elasticity was similar among species and did not change with water stress or plant age. Dry matter accumulation was smaller in the wild species than in the cultivated lines; water stress reduced shoot dry matter similarly in all species. However, water deficits significantly reduced the seed yield only in Hysun 31 and Seneca.

COMPETITIVE INTERACTIONS OF ALFALFA AND ANNUAL WEEDS AS AFFECTED BY ALFALFA WEEVIL (COLEOPTERA: CURCULIONIDAE) STUBBLE DEFOLIATION

1989 ◽  
Vol 24 (1) ◽  
pp. 78-83 ◽  
Author(s):  
G. David Buntin
Keyword(s):  
Dry Matter ◽  
Chenopodium Album ◽  
Dry Weight ◽  
Amaranthus Retroflexus ◽  
Dry Matter Accumulation ◽  
Weed Species ◽  
Alfalfa Weevil ◽  
Matter Production ◽  
Annual Weeds ◽  
The Impact

The impact of stubble defoliation by alfalfa weevil, Hypera postica (Gyllenhal), larvae on the establishment and growth of selected annual weeds in alfalfa was examined under controlled conditions in the greenhouse. Weed species were large crabgrass, Digitaria sanguinalis (L.) Scop., yellow foxtail grass, Setaria lutescens (Weig.) Hubb., redroot pigweed, Amaranthus retroflexus L. and common lambsquarters, Chenopodium album L. Stubble defoliation increased the survival of all weed species except foxtail grass. Dry matter production of aerial portions of crabgrass, foxtail grass, pigweed and lambsquarters was 28.4, 7.2, 23.7, and 7.3 times greater, respectively, when growing with defoliated than undefoliated alfalfa. Stubble defoliation also enhanced plant height and leaf number of most weed species. Stubble defoliation reduced dry matter accumulation and delayed development of alfalfa regrowth. Alfalfa root dry weight was more adversely affected than top dry weight by stubble defoliation. The presence of weeds did not significantly (P &gt; 0.05) affect the growth and development of defoliated and undefoliated alfalfa. This result suggests that stubble defoliation by alfalfa weevil larvae reduced the competitive ability of alfalfa which allowed weeds to grow and occupy gaps within the alfalfa canopy.

EFFECTS OF TEMPERATURE ON RATE AND DURATION OF KERNEL DRY MATTER ACCUMULATION OF MAIZE

1988 ◽  
Vol 68 (4) ◽  
pp. 935-940 ◽  
Author(s):  
M. TOLLENAAR ◽  
T. W. BRUULSEMA
Keyword(s):  
Growth Rate ◽  
Zea Mays ◽  
Dry Matter ◽  
Zea Mays L ◽  
Dry Weight ◽  
Controlled Environment ◽  
Dry Matter Accumulation ◽  
Linear Kernel ◽  
Effects Of Temperature ◽  
Kernel Growth

The response of rate and duration of kernel dry matter accumulation to temperatures in the range 10–25 °C was studied for two maize (Zea mays L.) hybrids grown under controlled-environment conditions. Kernel growth rates during the period of linear kernel growth increased linearly with temperature (b = 0.3 mg kernel−1 d−1 °C−1). Kernel dry weight at physiological maturity varied little among temperature treatments because the increase in kernel growth rate with increase in temperature was associated with a decline in the duration of kernel growth proportional to the increase in kernel growth rate.Key words: Zea mays L, period of linear kernel dry matter accumulation, controlled-environment conditions, kernel growth rate

scholarly journals Seasonal Partitioning of Leaf and Fruit Potassium and Fruit Dry Matter in French Prune Trees at Various Potassium Levels

1991 ◽  
Vol 116 (6) ◽  
pp. 981-986 ◽  
Author(s):  
F.J.A. Niederholzer ◽  
R.M. Carlson ◽  
K. Uriu ◽  
N.H. Willits ◽  
J.P. Pearson
Keyword(s):  
Dry Matter ◽  
Dry Weight ◽  
Fruit Growth ◽  
Growth Stages ◽  
Dry Matter Accumulation ◽  
Accumulation Rates ◽  
Mature Trees ◽  
Linear Relationships ◽  
Weight Yield ◽  
High K

A study was undertaken to determine the seasonal dynamics of leaf and fruit K content and the influence of tree K status and fruit growth on leaf and fruit K accumulation rates in French prune (Prunus domestics L. cv. d'Agen). Mature trees in a commercial orchard were treated with various rates of K2 SO4. (O to ≈20 kg/tree) in the fall. Fruit dry weight yield per tree at harvest and fruit K content were higher for high-K trees, but fruit percent K (by dry weight) was ≈1.0% for all trees. Leaf scorch and subsequent abscission severely reduced the canopy of K-deficient trees. Significant positive linear relationships between leaf and fruit K accumulation rates existed for the periods of 28 Apr.-28 May (May) and 28 May-7 July (June). A significant negative linear relationship existed between these two criteria from 7 July-3 Aug. (July). May (0.237 mg K per fruit-day) and July (0.267 mg K per fruit-day) mean fruit K accumulation rates were similar, but both were significantly higher (P = 0.001) than those for June (0.140 mg K per fruit-day). Mean leaf K accumulation rates for May (- 0.007 mg K per leaf-day) and July (-0.010 mg K per leaf-day) were similar, but both were significantly (P = 0.001) less than for June (0.005 mg K per leaf-day). Potassium per fruit accumulation was highest in trees with highest K status. Periods of net leaf K efflux and influx did not precisely correlate with fruit growth stages measured by fruit dry weight. The period of lowest fruit K accumulation (28 May-7 July) coincided with the period of maximum dry matter accumulation by the kernel. After 7 July, all increases in fruit dry weight and K content were due to mesocarp growth.

Dry Matter, Nodulation and Nutrient Uptake in Chickpea (Cicer arietinum) as Influenced by Irrigation and Phosphorus

1989 ◽  
Vol 25 (3) ◽  
pp. 349-355 ◽  
Author(s):  
S. S. Parihar ◽  
R. S. Tripathi
Keyword(s):  
Grain Yield ◽  
Nutrient Uptake ◽  
Irrigation Water ◽  
Vegetative Growth ◽  
Dry Matter ◽  
Dry Weight ◽  
Irrigation Scheduling ◽  
Dry Matter Accumulation ◽  
Pan Evaporation ◽  
Eastern India

SUMMARYThe response of chickpea to irrigation and phosphorus was studied at Kharagpur in Eastern India. Irrigation scheduling was based on the ratio between irrigation water applied and cumulative pan evaporation (ID/CPE), and had little effect on dry matter accumulation. Increasing the frequency and amount of irrigation reduced the number and dry weight of nodules per plant, which increased to a maximum 70 days after sowing and then declined. Irrigation significantly reduced grain yield as a result of excessive vegetative growth at the expense of pod formation. Application of phosphorus promoted nodulation and increased both nodule dry weight and the concentration of N, P and K in grain and stover. Uptake of N, P and K by the crop was also increased.

Effects of Drought and High Temperature on Grain Growth in Wheat

1984 ◽  
Vol 11 (6) ◽  
pp. 553 ◽  
Author(s):  
ME Nicolas ◽  
RM Gleadow ◽  
MJ Dalling
Keyword(s):  
Cell Division ◽  
High Temperature ◽  
Cell Size ◽  
Dry Matter ◽  
Cell Number ◽  
Limiting Factor ◽  
Dry Matter Accumulation ◽  
Starch Granules ◽  
Maximum Cell ◽  
Effects Of Drought

The effects of two levels of temperature and of water supply on grain development of wheat (cv. Warigal) were studied by imposing treatments during the early or late period of cell division. High temperature (28°C day/20°C night) accelerated development of the grain. Dry matter accumulation and cell division proceeded at a higher rate but had a shorter duration in the high temperature treatments. Maximum cell number, final cell size and the number of large starch granules per cell were not significantly reduced by high temperature. Drought and drought × high temperature reduced the storage capacity of the grain, with a decrease in number of cells and starch granules in the endosperm. Cell size was also reduced when treatments were imposed late during cell division. Duration of dry matter accumulation and cell division was reduced in the drought and drought × high temperature treatments. The combined effects of drought and high temperature were much more severe than those of each separate treatment. The amount of sucrose per cell was similar in all treatments. It appears unlikely that the supply of sucrose to the endosperm cells is the main limiting factor of dry matter accumulation in both drought and high temperature treatments.

Intercellular Invertase in Developing Peach Mesocarp

1988 ◽  
Vol 15 (3) ◽  
pp. 377 ◽  
Author(s):  
TD Ugalde ◽  
DJ Chalmers ◽  
PH Jerie
Keyword(s):  
Dry Matter ◽  
Prunus Persica ◽  
Total Activity ◽  
Insoluble Fraction ◽  
Acid Invertase ◽  
Dry Matter Accumulation ◽  
Tissue Slices ◽  
Insoluble Particles

Acid invertase (β-fructofuranosidase, EC 3.2.1.26) was extracted from peach mesocarp (Prunus persica (L.) Batsch) using a range of extraction conditions. The enzyme always was attached to insoluble particles in the crude homogenate and was bound by a mechanism that could not have arisen during extraction. The activity in the insoluble fraction made up (essentially) all of the total activity extracted from the tissue and was the same as the activity shown by whole tissue slices placed directly into the assay solution. These results demonstrate that most of the acid invertase in developing peach mesocarp is located outside the cell. The amount of this enzyme, as measured in vitro, did not change during development at times when the rate of dry matter increase was changing rapidly. Either the action of intercellular invertase is not associated with the control of dry matter accumulation in peach mesocarp, or control is effected through activity of the enzyme in vivo, not its synthesis or degradation.

SUCROSE AND SUCROSE SYNTHASE ACTIVITY DURING KERNEL DEVELOPMENT IN TRITICALE, WHEAT AND RYE

1985 ◽  
Vol 65 (4) ◽  
pp. 867-877 ◽  
Author(s):  
LEONARD SAARI ◽  
SEPPO O. SALMINEN ◽  
ROBERT D. HILL
Keyword(s):  
Sucrose Synthase ◽  
Dry Matter ◽  
Dry Weight ◽  
Dry Matter Accumulation ◽  
Kernel Development ◽  
Hexokinase Activity ◽  
Glucose Levels ◽  
Large Fluctuations ◽  
Substantial Decline ◽  
Sucrose Level

Developing triticale, wheat and rye grains were studied from 6 to 42 days postanthesis with respect to levels of sucrose and sucrose synthase activity. These were compared with levels of glucose and hexokinase activity as well as changes in dry weight and water content. Dry matter accumulation was linear in all cultivars and ceased at 26–34 days postanthesis, depending on the cultivar. Sucrose synthase activity was low in all tested cultivars at 3 days postanthesis and increased to near maximum levels by 15 days postanthesis. With the exception of triticale 6A190, maximum sucrose synthase activities were approximately 12 m units per seed and did not vary between cultivars. Triticale 6A190 had a maximum sucrose synthase activity of 16.5 m units per seed which occurred at about 21 days postanthesis. Sucrose synthase activity declined at maturity. Sucrose levels varied throughout kernel development. The extent of the variation differed amongst the tested cultivars. Triticale 6A190 had large fluctuations in sucrose level. Sucrose content changed from 1 mg per seed at day 12 to less than 0.1 mg/seed at day 18 to greater than 1 mg per seed at day 28. Hexokinase activity increased throughout kernel development with no substantial decline of activity at maturity. Glucose levels were highest during early kernel development and declined toward maturity. The variations in sucrose and sucrose synthase in triticale 6A190 suggest a malfunction in the metabolism of the line during kernel development. No direct relationship could be established, however, between these abnormalities and kernel shrivelling in 6A190.Key words: Sucrose, sucrose synthase, kernel development, triticale, wheat, rye, hexokinase

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