RESPONSE OF DURUM WHEAT CULTIVARS TO WATER STRESS IN THE FIELD AND GREENHOUSE

1983 ◽  
Vol 63 (4) ◽  
pp. 801-814 ◽  
Author(s):  
GETINET GEBEYEHOU ◽  
D. R. KNOTT

Experiments were conducted in the field and in the greenhouse to measure differences in drought resistance among durum wheat (Triticum turgidum L.) cultivars. Nine cultivars were tested in 1976 and 12 in 1977 in duplicate tests grown adjacent to each other under rainfed and irrigated conditions in the field. The drought resistance of the cultivars was measured as the difference in their performance under the two water regimes. For yield, there was no significant interaction between the cultivars and the water regimes in either year. Thus, the cultivars did not appear to differ significantly in drought resistance. They did differ significantly in the effect of water stress on the yield components. However, the performance of the cultivars was not consistent either for the yield components or between years. In one greenhouse experiment, six cultivars were grown in large containers. One set of plants was watered at regular intervals while a second set was watered only until 5 days after anthesis in the main spikes. Water stress caused major, correlated reductions in grain yield, 1000-kernel weight, and length of the growing period. However, the differences among the cultivars largely depended on their vegetative growth under nonstress, those with the most growth showing the largest reduction from stress. In a second greenhouse experiment, the 12 cultivars were grown in 15-cm pots at three moisture levels. For yield, there was no interaction between cultivars and moisture levels. Overall, the data provided little evidence of consistent differences among cultivars in resistance to moisture stress.Key words: Drought resistance, components of yield, yield, durum wheat (Triticum turgidum L.).

Agronomy ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 144 ◽  
Author(s):  
Rosa Mérida-García ◽  
Alison R. Bentley ◽  
Sergio Gálvez ◽  
Gabriel Dorado ◽  
Ignacio Solís ◽  
...  

Final grain production and quality in durum wheat are affected by biotic and abiotic stresses. The association mapping (AM) approach is useful for dissecting the genetic control of quantitative traits, with the aim of increasing final wheat production under stress conditions. In this study, we used AM analyses to detect quantitative trait loci (QTL) underlying agronomic and quality traits in a collection of 294 elite durum wheat lines from CIMMYT (International Maize and Wheat Improvement Center), grown under different water regimes over four growing seasons. Thirty-seven significant marker-trait associations (MTAs) were detected for sedimentation volume (SV) and thousand kernel weight (TKW), located on chromosomes 1B and 2A, respectively. The QTL loci found were then confirmed with several AM analyses, which revealed 12 sedimentation index (SDS) MTAs and two additional loci for SV (4A) and yellow rust (1B). A candidate gene analysis of the identified genomic regions detected a cluster of 25 genes encoding blue copper proteins in chromosome 1B, with homoeologs in the two durum wheat subgenomes, and an ubiquinone biosynthesis O-methyltransferase gene. On chromosome 2A, several genes related to photosynthetic processes and metabolic pathways were found in proximity to the markers associated with TKW. These results are of potential use for subsequent application in marker-assisted durum wheat-breeding programs.


2013 ◽  
Vol 64 (10) ◽  
pp. 957 ◽  
Author(s):  
S. Dura ◽  
M. Duwayri ◽  
M. Nachit ◽  
F. Al Sheyab

Durum wheat is one of the most important staple food crops, grown mainly in the Mediterranean region where its productivity is drastically affected by salinity. The objective of this study was to identify markers associated with grain yield and its related traits under saline conditions. A population of 114 F8 recombinant inbred lines (RILs) was derived by single-seed descent from a cross between Belikh2 (salinity-tolerant variety) and Omrabi5 (less salinity tolerant) was grown under non-saline and saline conditions in a glasshouse. Phenotypic data of the RILs and parental lines were measured for 15 agronomic traits. Association of 96 simple sequence repeat (SSR) loci covering all 14 chromosomes with 15 agronomic traits was analysed with a mixed linear model. In total, 49 SSR loci were significantly associated with these traits. Under saline conditions, 12 markers were associated with phenological traits and 19 markers were associated with yield and yield components. Marker alleles from Belikh2 were associated with a positive effect for the majority of markers associated with yield and yield components. Under saline condition, five markers (Xwmc182, Xwmc388, Xwmc398, Xbarc61, and Xwmc177) were closely linked with grain yield, located on chromosomes 2A, 3A, 3B, 4B, 5A, 6B, and 7A. These markers could be used for marker-assisted selection in durum wheat breeding under saline conditions.


1995 ◽  
Vol 75 (1) ◽  
pp. 55-60 ◽  
Author(s):  
T. N. McCaig ◽  
J. M. Clarke

Canadian durum wheat (Triticum turgidum L.) production is centred in the Brown and Dark Brown soil zones, areas of limited rainfall. For more than 50 yr, lines have been evaluated in the multi-location Durum Cooperative Test. Data from this test, over the period 1947–1992, were analyzed with the objectives of determining the advances that have been made within the Canada Western Amber Durum (CWAD) wheat class and comparing yield-related variables of recently registered cultivars with those of earlier cultivars. Canadian-developed cultivars have increased yields about 0.81% yr−1 relative to Hercules, or approximately 22.6 kg ha−1 yr−1. As kernel weight has remained unchanged, the genetic yield increases have resulted entirely from an increase in the number of kernels produced. Because kernel number is determined prior to, and during, anthesis, further yield increases may depend upon selection of genotypes that produce higher numbers of kernels, thereby increasing sink demand. While plant height and hectolitre weight have been decreasing over time, neither variable was significantly (P < 0.05) correlated with the yield increases that have taken place over the 29-yr period. The selection pressure toward shorter cultivars may have involved other agronomic advantages, such as decreased lodging. Days to maturity did not change significantly over time and was not correlated with yield. Key words:Triticum turgidum, kernel number, kernel weight, height, hectolitre weight


1997 ◽  
Vol 77 (2) ◽  
pp. 215-223 ◽  
Author(s):  
T. N. McCaig

Approximately 60% of Canadian durum wheat (Triticum turgidum L.) is produced in the semi-arid, Brown soil zone of southern Saskatchewan. The Durum Wheat Cooperative Test (DWCT) provides the means of evaluating potential new cultivars, and has been grown at Swift Current, located near the centre of the Brown soil zone in Saskatchewan, for more than 50 yr. Historical yield-related data from the DWCT were analyzed in conjunction with daily precipitation and maximum daily temperature (MaxDT) data with the objective of improving our understanding of the effects of these weather variables on durum wheat grown in this semi-arid region.The highest correlation between the weather variables and grain yield was during the period near the end of June through early July, approximately the time of anthesis. The correlation with kernel number m−2 (KNum) was maximum near the end of June, while the correlation with kernel weight was highest around the third week of July. The maximum effect of these weather factors in limiting yield in the Brown soil zone was through an impact on KNum around anthesis. Hectolitre weight and time-to-maturi-ty appeared to be influenced mainly by the weather in July, while crop height was determined by the weather near the end of June. An analysis which examined cumulative heat-units above threshold MaxDT of 20, 24, 28 and 32 °C indicated that temperatures >24 °C may be detrimental during early June although high temperatures are less common in June than in July. Yield was also negatively impacted by temperatures >20 °C during the first 3 wk of July.Future yield gains in this semi-arid region may be dependent upon the development of cultivars which are more tolerant of drought and high-temperature stress at anthesis. Key words: Triticum turgidum, kernel number, kernel weight, height, maturity, hectolitre weight


2012 ◽  
Vol 60 (4) ◽  
pp. 309-317 ◽  
Author(s):  
J. Bányai ◽  
É. Láng ◽  
Z. Bognár ◽  
C. Kuti ◽  
T. SpitkÓ ◽  
...  

The effect of irrigation water on the yield and on individual yield components was examined for 19 durum wheat varieties by continually recording weather data and carrying out measurements on the moisture content, temperature, electrical conductivity and tension of the soil. Dry (rain-fed) and irrigated treatments were included in the experiment, which was carried out in the framework of the EU FP7-244374 DROPS project.During the rainless spring of 2011 the soil moisture content of the non-irrigated area dropped to 21–22 vol% and the effect of drought stress was still felt at harvest. The quantity of irrigation water applied during the growing season ensured normal conditions for generative development and a significant difference could be detected between the yield components in the two treatments. The thousand-kernel weight of the varieties was identical in the dry and irrigated plots, but in response to irrigation there was an increase in the number of grains per ear and the grain weight, and an improvement in fertilisation, resulting in higher yields.


1978 ◽  
Vol 58 (3) ◽  
pp. 321-323 ◽  
Author(s):  
J. B. BOLE ◽  
S. DUBETZ

Seven soil supplement products did not affect grain or straw yields, or any of the measured yield components of unstressed wheat or of wheat subjected to an 8-bar soil water stress at early heading. Soil water stress reduced yields by reducing the number of spikes per plant and, to a lesser but significant degree, the number of kernels per spike and the average kernel weight.


2002 ◽  
Vol 29 (1) ◽  
pp. 35 ◽  
Author(s):  
Eduardo A. Tambussi ◽  
Jaume Casadesus ◽  
Sergi Munné-Bosch ◽  
José Luis Araus

We analysed the photoprotective response in water-stressed plants of durum wheat (Triticum turgidum L. var. durum cv. Mexa). The plants were grown in a greenhouse for 4 weeks and then exposed to water stress by withholding water for 8 d. Development of water stress was monitored as the decrease in relative water content (RWC) and net CO2 assimilation of the last fully developed leaf. The photoprotective response was evaluated in the same leaves by analysing modulated chlorophyll fluorescence, leaf spectroradiometrical changes, and pigment content. Measurements were performed 3, 6 (moderate stress) and 8 (severe stress) d after water-stress treatment began. The non-photochemical quenching of chlorophyll fluorescence (qN), as well as the contents of zeaxanthin and antheraxanthin increased significantly after 6 d of treatment. However, a further rise in these xanthophylls on day 8 was not associated with any increase in qN. In addition, the β-carotene content rose significantly on day 8, suggesting an increase in antioxidant defences. The photochemical index (PI), derived from spectroradiometrical measurements, showed a strong progressive drop on days 6 and 8, which was paralleled by an increase in the de-epoxidation state of the xanthophyll cycle (DPS), in particular by the zeaxanthin content. At midday, PI was strongly (negatively) correlated with DPS and qN. These results suggest that the PI may be a reliable indicator of photoprotection in the study of plant stress, and in breeding programs.


Sign in / Sign up

Export Citation Format

Share Document