Water Relations of the Developing Wheat Grain

1980 ◽  
Vol 7 (5) ◽  
pp. 519 ◽  
Author(s):  
EWR Barlow ◽  
JW Lee ◽  
R Munns ◽  
MG Smart
Keyword(s):  
Water Deficit ◽  
Flag Leaf ◽  
Maximum Level ◽  
Grain Filling ◽  
Controlled Environment ◽  
Wheat Grain ◽  
Grain Filling Period ◽  
Pigment Strand ◽  
Days After Anthesis ◽  
Wheat Spike

The physiological and anatomical mechanisms underlying the reduced sensitivity of wheat grain growth to water deficits in the post anthesis period have been investigated. The water potential (Ψ) and water content of the developing wheat grain and of other tissues within the wheat spike and flag leaf were compared under controlled environment and field conditions. In the 14 days following anthesis when the amount of water in each grain was increasing, the Ψ gradient between the grain and the rest of the plant was most pronounced. This Ψ gradient disappeared when the water per grain reached its maximum level (15 days after anthesis). The apparent turgor potential (P) of the wheat grain was very small (less than 0.2 MPa) throughout the grain filling period. When water was withheld 10 and 20 days after anthesis, the grain Ψ changed little despite a large decrease in the Ψ of the glumes, rachis and flag leaf. Grain Ψ showed the same independence during a diurnal cycle of water deficit. The independence of grain Ψ under water deficit conditions may be related initially to the xylem discontinuity in the floral axis and, in longer-term water stress situations, to the deposition of lipid in the pigment strand of the grain itself.

scholarly journals Spring barley performances in the Pannonian zone

Genetika ◽  
2012 ◽  
Vol 44 (3) ◽  
pp. 499-512 ◽  
Author(s):  
Novo Przulj ◽  
Vojislava Momcilovic
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Genetic Variability ◽  
Plant Height ◽  
Water Deficit ◽  
Environmental Conditions ◽  
Spring Barley ◽  
Grain Filling ◽  
Growing Seasons ◽  
Grain Filling Period

Environmental conditions in the Pannonian zone can be characterized with moderate high temperature and partially water deficit during grain filling of spring barley, although low temperature and water deficit are possible also in period till anthesis. This study was conducted to evaluate the variation of the duration of the period from emergence to anthesis (VP), duration of grain filling period (GFP), plant height (PH), spikes number m-2 (SN), grains number spike-1 (GN), thousand grains weight (GW) and yield (YIL) in spring two-rowed barley in conditions of the Pannonian zone. All three factors; genotype, environment and the interaction GxY affected the studied traits. Average VP was 777 GDD, GFP 782 GDD, PH 78 cm, SN 523, GN 28.2, GW 43.2 g and YIL 6.26 t ha-1. Variation across varieties was higher than across growing seasons. Heritability varied from 0.66 for YIL to 0.94 for VP and GFP. This study confirmed that a sufficiently large genetic variability must be base for selecting appropriate varieties for the Pannonian zone conditions. In order to determine high yielding and quality barley extensive research in relation to breeding, variety choice for production and growing practice must be done.

scholarly journals Soil drying and rewatering applied at three grain developmental stages affect differentially growth and grain protein deposition in wheat (Triticum aestivum L.)

2006 ◽  
Vol 18 (2) ◽  
pp. 341-350 ◽  
Author(s):  
José Beltrano ◽  
Marta Guillermina Ronco ◽  
María Cecilia Arango
Keyword(s):  
Water Stress ◽  
Water Deficit ◽  
Developmental Stages ◽  
Flag Leaf ◽  
Grain Filling ◽  
Kernel Weight ◽  
Yield Losses ◽  
Protein Patterns ◽  
Grain Number Per Spike ◽  
Ripe Stage

Water deficits cause large yield losses in wheat. Although anthesis is generally considered the most vulnerable period, water deficit during grain filling can also cause yield losses. The objective of this study was to investigate the effect of water stress and rewatering, at three different grain developmental stages, on physiological and grain filling parameters and on yield components. Wheat plants were subjected to water deficit and rewatering at the watery ripe, milk and soft dough stages. In the flag leaf, water stress decreased the relative water content, the chlorophyll and protein content and increased the leakage of solutes, at all three studied grain filling stages. Water stress at the watery ripe and milk stages reduced the final grain dry mass by 47 % and 20 %, respectively. This reduction was due to a decrease in the grain filling period and to a significant reduction in the maximum rate of grain-fill. Water stress imposed at the watery ripe stage reduced not only the linear growth phase but also its slope; grain number per spike and the 1000-kernel weight were also significantly reduced. SDS-PAGE patterns of grain proteins at the watery ripe stage did not differ between the controls, stressed or rewatered treatments. Protein patterns at the milk stage changed substantially with water stress, mainly for the high molecular weight glutenin subunits and gliadins. Three new bands were observed with apparent molecular weights of 108.5 kDa, 84.8 kDa and 63 kDa. Rewatering reverted water stress effects when it was imposed at the milk stage. Water deficit at the soft dough stage did not have any effect on protein grain patterns.

scholarly journals Correlation and path analysis in recombinant inbred lines (RILs) of wheat (Trticum aestivum L.)

2016 ◽  
Vol 8 (2) ◽  
pp. 826-832
Author(s):  
Ramesh Ramesh ◽  
Shailesh Marker ◽  
S. Muniswamy ◽  
Yamanura Yamanura
Keyword(s):  
Grain Yield ◽  
Recombinant Inbred ◽  
Recombinant Inbred Lines ◽  
Flag Leaf ◽  
Correlation Coefficients ◽  
Grain Filling ◽  
Inbred Lines ◽  
Spike Length ◽  
Grain Filling Period ◽  
Selection Of

Correlation and path coefficient analysis were studied in 22 heat tolerant Recombinant Inbred Lines (RILs) of wheat. Analysis of variance revealed the significant difference among genotypes for all the characters. Suggested that there was ample scope for selection of promising RILs for yield improvement. A wide range of variability was exhibited by most of the traits. The results of correlation studies indicated that genotypic correlation coefficients were higher in magnitude than their corresponding phenotypic correlation coefficients for all the traits which indicated that association among these characters was under genetic control and indicating the preponderance of genetic variance in expression of characters. Grain yield per plant had high, significant and positive association with number of grains per spike, spike weight, spike length, canopy temperature depression, tillers per plant, grain filling period and chlorophyll content both at genotypic and phenotypic levels indicating that these traits were main yield attributing traits. Path analysis revealed that grains per spike, tillers per plant, spike length, had the highest positive direct effect on grain yield followed by flag leaf length, flag leaf width, days 50% heading, plant height, grain filling period, membrane stability and days to maturity at genotypic level. The selection of characters such as grains per spike, tillers per plant, spike length and spike weight would be helpful for further improvement in RILs of wheat.

Gas exchange rates and nitrogen concentrations in two winter wheat cultivars during the grain-filling period

1980 ◽  
Vol 58 (19) ◽  
pp. 2110-2116 ◽  
Author(s):  
W. N. Migus ◽  
L. A. Hunt
Keyword(s):  
Winter Wheat ◽  
Flag Leaf ◽  
Grain Filling ◽  
Wheat Cultivars ◽  
N Concentration ◽  
Nitrogen Concentrations ◽  
Winter Wheat Cultivars ◽  
N Treatment ◽  
Grain Filling Period ◽  
Rate Of Decline

CO2 exchange (CER) and transpiration (TR) rates of flag leaves, penultimate leaves, and the ear of two winter wheat cultivars (cv. Fredrick and cv. Bezostaya-1), were measured at intervals during the life of the flag leaf. These were grown at two levels of nitrogen (N), 105 and 210 mg L−1, supplied from the double ridge stage of apical development. Nitrogen concentrations and dry weights of the flag and penultimate leaves, and of various other plant parts, were also measured.CER of main culm flag leaves of both cultivars declined more slowly from ear emergence to approximately 2.5 weeks postanthesis than either before or after this period. Similarly, the CER pattern of main culm penultimate leaves of Fredrick showed a plateau during this same period. By contrast, CER of the penultimate leaves of Bezostaya declined more uniformly overtime. CER of illuminated ears declined steadily from anthesis, whereas CER in the dark decreased to a maximum negative value approximately 2 weeks postanthesis. Nitrogen treatment had little effect on these CER patterns, with the exception of Bezostaya penultimate leaves, in which the rate of decline was slower for the higher N treatment.Nitrogen concentrations of the flag and penultimate leaves, and in the nongrain ear component, decreased steadily during the grain-filling period for both cultivars and N treatments. Leaf N concentration also decreased during the preanthesis period in Fredrick at both N treatments, and in Bezostaya at the lower N treatment. The time – course of N concentration in the leaves was not closely mirrored by CER, indicating that factors other than the N concentration of the leaves were important in determining the pattern of CER.TR of the flag and penultimate leaves declined from full flag leaf expansion until anthesis and then rose during a 2- to 2.5-week-postanthesis period for both cultivars and N treatments, with the exception of Bezostaya at the lower N treatment. The increase in TR during the filling period suggests that the reduced rate of decline in CER at that time may have resulted, at least partly, because a reduction in gas phase resistance offset an increase in residual resistance.

Effects of light, temperature, and rate of desiccation on translucency in wheat grain

1968 ◽  
Vol 19 (3) ◽  
pp. 365 ◽  
Author(s):  
JA Parish ◽  
NJ Halse
Keyword(s):  
Low Temperatures ◽  
Dry Weight ◽  
Grain Filling ◽  
Wheat Grain ◽  
Low Light ◽  
Wide Range ◽  
Grain Drying ◽  
Drying Techniques ◽  
Laboratory Results ◽  
Grain Filling Period

Wheat grain was harvested at maximum dry weight and dried under various conditions in the laboratory. Results showed that opaque grain was produced by fast drying; translucency developed with slow drying. The effect of various temperatures when drying rate was constant was also measured. It was found that translucency developed more at high temperatures than at low temperatures. There was little "mottling" despite the wide range between treatments from entirely opaque to fully translucent grain. Drying techniques were found whereby grain samples different in texture but identical in other respects can be prepared. In other experiments wheat plants were grown in controlled light and temperature conditions during the grain-filling period. Results showed that at this stage low temperature and low light intensity favoured the development of translucency.

scholarly journals Effects of successive applications of maneb and benomyl on growth and yield of five wheat varieties of different heights.

1973 ◽  
Vol 21 (4) ◽  
pp. 282-296
Author(s):  
J.H.J. Spiertz
Keyword(s):  
Grain Yield ◽  
Flag Leaf ◽  
Combined Treatment ◽  
Grain Filling ◽  
Growth And Yield ◽  
Septoria Tritici ◽  
Wheat Varieties ◽  
Leptosphaeria Nodorum ◽  
Culm Length ◽  
Grain Filling Period

Wheat cv. Juliana (culm length 117 cm), Manella (82 cm), Lely (80 cm), Mex-cross (69 cm) and Gaines (79 cm) were sprayed twice before flowering with 2 kg maneb/ha and twice after flowering with 1 kg benomyl/ha. Combined treatment greatly delayed the spread of Septoria tritici and S. nodorum in the crop, the flag leaf remained green longer, the grain filling period was lengthened, and the growth rate of the grain between the milk stage and the dough stage was increased from 204 to 230 kg/ha day; effects were greater in the susceptible cultivars Lely and Gaines. Increases in grain yield were 14, 23, 32, 16 and 42% for the 5 cultivars, respectively. The green area of the flag leaf accounted for 85% of the variance in grain yield. The degree of disease infection was not significantly correlated with culm length or amount of leaf area. ADDITIONAL ABSTRACT: Spraying with maneb at 2 kg/ha twice before flowering and with benomyl at 1 kg/ha twice after flowering greatly delayed the spread of Septoria tritici and S. [Leptosphaeria] nodorum and increased yields, particularly in the 2 susceptible cvs. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Persistence of Non-Crease Protophloem Strands in the Developing Wheat Grain

1990 ◽  
Vol 17 (2) ◽  
pp. 223 ◽  
Author(s):  
DB Fisher
Keyword(s):  
Grain Filling ◽  
Wheat Grain ◽  
Grain Filling Period

The two protophloem strands in the lateral ovary walls of the developing wheat grain, previously reported to be obliterated during grain elongation, are shown to persist through about half, or somewhat longer, of the grain filling period. During the latter part of their functional life, they appear to be involved in the absorption of solutes produced during degeneration of the middle pericarp. During the final stages of pericarp degeneration, the protophloem strands show a basipetal progression of degeneration and adherence to the remaining inner and outer pericarp layers.

scholarly journals Wheat Grain Filling Is Limited by Grain Filling Capacity rather than the Duration of Flag Leaf Photosynthesis: A Case Study Using NAM RNAi Plants

PLoS ONE ◽  
2015 ◽  
Vol 10 (8) ◽  
pp. e0134947 ◽  
Author(s):  
Philippa Borrill ◽  
Brendan Fahy ◽  
Alison M. Smith ◽  
Cristobal Uauy
Keyword(s):  
Flag Leaf ◽  
Grain Filling ◽  
Leaf Photosynthesis ◽  
Wheat Grain ◽  
Filling Capacity
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