Efficiency of water use by irrigated wheat in the Sudan

1969 ◽  
Vol 73 (2) ◽  
pp. 261-266 ◽  
Author(s):  
A. H. El Nadi

SUMMARYField experiments were conducted to study the differential responses of a wheat crop to water stress during different stages of its growth. Evidence was produced to show that both the flowering phase and the stage of grain filling and maturation were more sensitive to drought than the vegetative period of growth. Yield of wheat was not reduced when the crop suffered from cycles of water stress induced during the vegetative period, if the crop received favourable water regimes thereafter. Efficiency of water utilization from different water treatments was assessed. There was no relation between the protein and starch contents of the grain and the type of water treatment.The effects of different water treatments on crop development and on components of yield were studied.

Euphytica ◽  
2021 ◽  
Vol 217 (3) ◽  
Author(s):  
Gareth J. Norton ◽  
Anthony Travis ◽  
Panthita Ruang-areerate ◽  
Graeme W. Nicol ◽  
Ayotunde A. Adeosun ◽  
...  

AbstractIt has been estimated that up to 90% of human exposure to cadmium is through food, and that cadmium within rice grains can be a major contributor to that dietary source. In this study genome wide association mapping was conducted on the Bengal and Assam Aus Panel (BAAP) of rice to identify quantitative trait loci and candidate genes for lowering grain cadmium. Field experiments were conducted over two years under two different irrigation systems: continually flooded and alternate wetting and drying (AWD). There was significant effects of water treatment, genotype, and genotype by water treatment interaction. Importantly, AWD increased grain cadmium, on average, by 49.6% and 108.8% in year 1 and 2 respectively. There was between 4.6 and 28 fold variation in cadmium concentration. A total of 58 QTLs were detected but no loci are clearly specific to one water regime despite approximately 20% of variation attributable to genotype by water regime interaction. A number of QTLs were consistent across most water treatments and years. These included QTLs on chromosome 7 (7.23–7.61, 8.93–9.04, and 29.12–29.14 Mbp), chromosome 5 (8.66–8.72 Mbp), and chromosome 9 (11.46–11.64 Mbp). Further analysis of the loci on chromosome 7 (8.93–9.04 Mbp), identified the candidate gene OsNRAMP1, where cultivars with a deletion upstream of the gene had higher concentrations of cadmium compared to the cultivars that did not have the deletion. The distribution of alleles within the BAAP suggest this QTL is easily detected in this population because it is composed of aus cultivars. Local genome cluster analysis suggest high Cd alleles are uncommon, but should be avoided in breeding.


1955 ◽  
Vol 8 (4) ◽  
pp. 435 ◽  
Author(s):  
RF Williams ◽  
RE Shapter

A comparative study of growth and nutrition in barley and rye was made with two water treatments. The low-water treatment was of an intermittent character and harvests were made after each of the five periods of water stress. Yield reductions due to low-water treatment were highly significant at all five harvests and for both species. The severity of the effects on various plant parts was conditioned by the stage of development of those parts.


1983 ◽  
Vol 34 (3) ◽  
pp. 229 ◽  
Author(s):  
GK McDonald ◽  
BG Sutton ◽  
FW Ellison

The effect of time of sowing on the yield of 15 wheat cultivars grown under irrigation was examined at Narrabri, N.S.W. Sowing dates, which ranged from mid-April to mid-August, encompassed the period of sowing normally found with commercial crops. The length of the pre-anthesis period was affected by both temperature and photoperiod. There was evidence of a vernalization requirement for some of the winter and midseason cultivars, but, overall, photoperiod was the more important environmental factor determining pre-anthesis development. Each day's delay in sowing caused a delay of between 0.48 and 0.75 days in anthesis; the delays observed for spring wheats were generally greater than those reported for dryland wheat in eastern Australia. Winter cultivars generally did not show an optimum sowing or anthesis date. For spring cultivars, the optimum time of sowing was early June (range of about 3 weeks), while the optimum anthesis date was the last week of September (range of 1 week). Grain yields of spring cultivars were reduced by 6 and 16% per week's delay in sowing and anthesis respectively. Despite a non-limiting water supply, yields at late plantings were low, which was largely the result of hastened crop development and high temperatures during grain-filling. The environmental factors which determined the optimum sowing and anthesis dates were the incidence of early spring frosts and high spring temperatures. If frosts were not a factor at Narrabri, the optimum time of flowering would be 6-8 weeks earlier than the present optimum.


2022 ◽  
Vol 82 ◽  
Author(s):  
N. Hussain ◽  
A. Yasmeen ◽  
M. M. Yousaf ◽  
W. Malik ◽  
S. Naz ◽  
...  

Abstract Water stress is one of the major factor restricting the growth and development of chickpea plants by inducing various morphological and physiological changes. Therefore, the present research activity was designed to improve the chickpea productivity under water stress conditions by modulating antioxidant enzyme system. Experimental treatments comprised of two chickpea genotypes i.e. Bhakhar 2011 (drought tolerant) and DUSHT (drought sensitive), two water stress levels i.e. water stress at flowering stage and water stress at flowering + pod formation + grain filling stage including well watered (control) and three exogenous application of nutrients i.e. KCl 200 ppm, MgCl2, 50 ppm and CaCl2, 10 mM including distilled water (control). Results indicated that water stress at various growth stages adversely affects the growth, yield and quality attributes of both chickpea cultivars. Exogenous application of nutrients improved the growth, yield and antioxidant enzyme activities of both chickpea genotypes even under water stress conditions. However, superior results were obtained with foliar spray of potassium chloride on Bhakhar 2011 under well-watered conditions. Similarly, foliar spray of potassium chloride on chickpea cultivar Bhakhar 2011 cultivated under stress at flowering + pod formation + grain filling stage produced significantly higher contents of superoxide dismutase, peroxidase and catalase. These results suggests that the application of potassium chloride mitigates the adverse effects of water stress and enhanced tolerance in chickpea mainly due to higher antioxidant enzymes activity, demonstrating the protective measures of plant cells in stress conditions.


Author(s):  
Adnan Al-ghawry ◽  
Attila Yazar ◽  
Mustafa Unlu ◽  
Celaleddin Barutcular ◽  
Yeşim Bozkurt Çolak

Abstract A field experiment was carried out to evaluate the effect of different conventional and supplemental irrigation strategies on leaf stomatal conductance (gs) and chlorophyll content (SPAD) yield and irrigation water productivity (IWP) of wheat using sprinkler line source in 2014 and 2015 in the Mediterranean region. The irrigation strategies were, supplemental irrigation (SI) during flowering and grain filling (SIFG), SI during grain filling (SIG), SI during flowering (SIF) and conventional irrigation (CI). These strategies were conducted under four irrigation levels 25, 50, 75, 100% and a rain-fed as control. The results indicated that CI100 and CI75 produced the greater grain yield and IWP, respectively. CI100 resulted in the increased chlorophyll content by 8.8% over rain-fed. The results confirmed that the SPAD and stomatal conductance values were not equally sensitive to water stress during growth stages. The wheat crop suffered a greater SPAD and gs reductions when the water stress occurred during the grain filling stage (SIF strategy) compared to other strategies, which means that the grain filling stage is more sensitive and effective to decrease the yield of winter wheat. The higher grain yields were achieved when the seasonal mean gs reached 207.4 mmol/m2s in CI and 169.2 mmol/m2s in SI, and the stomatal closure responded well to low, moderate and severe drought treatments. The leaf stomatal conductance (gs) was correlated linearly with grain yield. These relations could be used as a physiological indicator to evaluate water stress effect on the growth and productivity of wheat.


Genome ◽  
2009 ◽  
Vol 52 (5) ◽  
pp. 419-430 ◽  
Author(s):  
A. Ebrahimi ◽  
P. Maury ◽  
M. Berger ◽  
A. Calmon ◽  
P. Grieu ◽  
...  

The purpose of this study was to identify genomic regions controlling seed protein content, kernel and hull weights, and seed density in water-stress conditions in sunflower ( Helianthus annuus L.). The experiments consisted of a split-plot design (water treatment and recombinant inbred lines) with three blocks in two environments (greenhouse and field). High significant variation was observed between genotypes for all traits as well as for water treatment × genotype interaction. Several specific and nonspecific QTLs were detected for all traits under well-watered and water-stress conditions. Two SSR markers, ORS671_2 and HA2714, linked to protein content were identified that have no interaction with water treatments in greenhouse conditions. We also detected the E35M60_4 marker associated with kernel weight that had no interaction with water treatments. A specific QTL for protein content was detected with important phenotypic variance (17%) under water-stress conditions. Overlapping QTLs for protein content and seed density were identified in linkage group 15. This region probably has a peliotropic effect on protein content and seed density. QTLs for protein content colocated with grain weight traits were also identified.


2011 ◽  
Vol 39 (2) ◽  
pp. 196 ◽  
Author(s):  
Nurdilek GULMEZOGLU ◽  
Nihal KAYAN

This research aimed to determine the effect of different levels of nitrogen (N) on the growth, yield and the N accumulation of lentil plants grown under rain-fed conditions. The two-year field experiments with lentil were arranged in a randomised complete block design. Nitrogen was applied at four rates (0, 20, 40 and 60 kg ha-1) and all of the plots received half of the N rates before sowing in October and the remaining N rate in spring. The plants were harvested in the following stages: the first multifoliate leaf unfolding at the fifth node (V5) full seed or seed on nodes 10-13 that fill pod cavities (R6) and maturity (R8). The dry weight and N concentration of the shoot (leaf+stem), pod wall, and seed were then measured. It has been found that N application significantly affected the lentil characteristics. The maximum biomass accumulation and N accumulation were obtained at R6, and the N fertiliser had a positive effect on the seed weight and N accumulation. It can be suggest that 20 kg N ha-1 will increase the per-plant dry matter and N accumulation of the seeds under rain-fed conditions.


2006 ◽  
Vol 57 (12) ◽  
pp. 1307 ◽  
Author(s):  
J. M. Virgona ◽  
F. A. J. Gummer ◽  
J. F. Angus

The effect of grazing by sheep during the late vegetative and early reproductive phases was measured on long-duration wheat crops in 2 experiments on farms in southern NSW. In both experiments, grazed and non-grazed crops were compared with different N-fertiliser strategies. In the first experiment, grazing 40 dry-sheep equivalents (DSE)/ha for 19 days increased grain yield from 2.30 to 2.88 t/ha in a season with a dry early spring. The second experiment, in a more favourable season, compared 6 durations of grazing by an average of 32 DSE/ha. The effects of grazing varied from no yield reduction with 15 days of grazing to a reduction from 5.97 to 3.98 t/ha with 51 days of grazing. In both experiments grazing caused slower crop development, with about 1 day’s delay in anthesis and maturity for every 4–5 days of grazing. Different patterns of water use by grazed and non-grazed crops, combined with delayed development, explained much of the effects of grazing on yield. The soil accumulated more water during grazing, which was used during grain filling when water-use efficiency for grain production was high. Delayed development also allowed grazed crops to respond to later rain. In the second experiment, grazing resulted in a net loss of 38 kg N/ha from the crop. Despite reduced N levels, the grazed crops showed no greater ability than grain-only crops to recover fertiliser N. The effect of the low recovery was that N removed during grazing was not efficiently replaced by fertiliser.


Soil Research ◽  
1987 ◽  
Vol 25 (4) ◽  
pp. 499 ◽  
Author(s):  
WS Meyer ◽  
FX Dunin ◽  
RCG Smith ◽  
GSG Shell ◽  
NS White

Wheat is being grown increasingly in the irrigated areas of south-east Australia. Its profitability depends on high yields, which in turn, are highly dependent on accurate water management. This combination, together with the increasing need for greater water use efficiency to minimize accessions to rising water-tables, calls for effective irrigation scheduling. To achieve this, accurate estimates of crop water use and upward fluxes of water into the root zone from shallow water-tables are required. A weighing lysimeter, installed in 1984, measured hourly evaporation (Ea) from a wheat crop which enabled the accuracy of water use estimates to be assessed. Daily potential evaporation (Ep) was calculated from a combination equation previously calibrated over lucerne, while previously developed crop coefficients for wheat were used to convert Ep to estimated Ea. Daily Ea was the major component in a water balance model for irrigated wheat. The model was quite efficient (r2 = 0.911, but with a bias of -8.8%, which indicated that Ea values were generally underestimated. The underestimate was due primarily to the wind function used in the calculation of Ep, and alternative functions for both daily and hourly calculations were derived. The 1984 lysimeter data also showed that change in soil water content was accurately measured with the field-calibrated neutron probe. Comparisons of measured and estimated water use from field experiments in 1981 and 1982 indicated that upward flux from a water-table between 1 a5 and 2.1 m below the soil surface may be up to 30% of daily Ea. This upward flux will need to be taken into account if irrigation scheduling is to promote efficient use of irrigation water.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Yuzhan Li ◽  
Luxin Liang ◽  
Xiaomeng Fu ◽  
Zifeng Gao ◽  
Hecheng Liu ◽  
...  

Abstract The effect of light and water on aromatic rice remain largely unclear. A pot experiment was conducted to investigate the influences of light-water treatments (CK: natural light and well-watered conditions, WS: natural light and water-stressed conditions, LL: low light and well-watered conditions, LL-WS: low light and water-stressed treatment) on yield and 2-acetyl-1-pyrroline (2AP) formation in aromatic rice. Compared with CK, the light-water treatments decreased grain yield (10.32–39.19%) due to reductions in the filled grain percentage and total dry weight, in the regulation of biomass distribution, and in the attributes of gas exchange and antioxidant response parameters. The 2AP content in grains increased in the LL treatment (5.08–16.32%) but decreased in the WS treatment compared with that in CK. The changes in 2AP were associated with changes in 2AP formation-related traits and element content. Low light and water stress led to yield declines in aromatic rice, but low light alleviated the decrease in 2AP content caused by water stress.


Sign in / Sign up

Export Citation Format

Share Document