Evaluation of cellular thermotolerance and associated heat tolerance in wheat (Triticum aestivum L.) under late sown condition

Author(s):  
Chubasenla Aochen ◽  
Pravin Prakash

Fifty wheat genotypes were evaluated at the seedling stage of growth, for genetic variation in cellular thermotolerance by cell membrane thermostability (CMS) and Triphenyl tetrazolium choride (TTC) assays. A subset of eight genotypes was also evaluated at the anthesis stage using the same assays. Large and significant differences existed among wheat genotypes for TTC and CMS at the seedling and anthesis stages. Average thermotolerance declined from seedling to anthesis stage. Thermotolerance was well-correlated between growth stages among the eight genotypes for both CMS (r=0.95; p= 0.01) and TTC (r=0.92; p= 0.01). The correlation between TTC and CMS among the eight genotypes at seedling and anthesis stages was significant (r=0.95; p=0.01 and r =0.93; p= 0.01, respectively). The effect of heat stress on wheat genotypes selected on the basis of TTC and CMS thermotolerance ratings were evaluated. 1000-grain weight, grain filling duration (GFD) and grain filling rate (GFR) reduced under heat stress. The heat susceptibility index (S) revealed K-65 and Yangmai6 to be susceptible and NW-1014 and DBW-14 to be moderately tolerant to heat stress. GFR and 1000-grain weight were found to have highly significant positive correlation with CMS and TTC ratings at both seedling and anthesis stages.

Author(s):  
Rajbir Yadav ◽  
Ashish Kumar ◽  
Soma Gupta ◽  
K. B. Gaikwad ◽  
Neelu Jain ◽  
...  

Increase in ambient temperature beyond threshold level as predicted by global climate models may impact wheat production severely in India if it happens during grain filling stage. Grain filling rate (GFR) and grain filling duration (GFD) are critical determinant for final grain yield realization in wheat. GFR in wheat follow a slow-fast-slow pattern, however, wheat genotypes may have quantitative differences in this pattern. Ninty six diverse wheat genotypes were evaluated for GFR in two phases i.e. during first 20 days after anthesis and thereafter up to physiological maturity and grain filling duration. Out of 96 genotypes, six namely, G958, G1203, G1219, G1275, HD2985 and HDCSW18 were having high GFR during initial phase while seven genotypes viz., G949, G1081, G1124, G1159, G1204, HD3059 and HD2380 exhibited high GFR at terminal phase of grain development. Genotypes, G1263, G1207, G1423 along with some of the released varieties, HD2285, WH1105 and HD2864 were having higher GFD. Correlation between the two traits were not significant (r = -0.17959). ANOVA for GFR and GFD indicated highly significant variability among the genotypes. QTLs identified for GFR and GFD elsewhere were validated in Indian breeding material under conservation agriculture. Two SSR markers viz., XCfd42 and Xwmc500 explained about 6% and 1% variation for GFR, respectively. Similarly, already reported marker Xwmc382 was able to explain about 8% of variation for GFD in the Indian breeding material. It has been postulated from the study that by crossing the genotypes with high GFR in different grain growth stages like HD CSW 18 and HD 3059, genotypes with consistently high grain filling rate throughout the grain growth stage can be developed. The markers XCfd42 and Xwmc 382 can be further explored for fine mapping to integrate in the breeding programme for selection.


2017 ◽  
Vol 5 (2) ◽  
pp. 188-193 ◽  
Author(s):  
Ankur Poudel ◽  
Dhruba Bahadur Thapa ◽  
Manoj Sapkota

High temperature stress adversely affects plant physiological processes; limiting plant growth and reducing grain yield. Heat stress is often encountered due to late sowing of wheat in winter. Fifty wheat genotypes were studied for days to maturity, thousand kernel weight, grain filling duration, grain filling rate, and SPAD reading in alpha lattice design at Agriculture and Forestry University at Rampur, Chitwan, Nepal with the objective to identify superior heat stress tolerant varieties after clustering them based on their response to heat stress. All the genotypes were clustered using reduction in thousand kernel weight, heat susceptibility index for thousand kernel weight, heat susceptibility index for grain filling duration, area under SPAD retreat curve, maturity duration under normal condition, maturity duration at late sown condition, grain filling rate under normal condition and grain filling rate at late sown condition as variables and dendogram was prepared. UPGMA revealed that these genotypes formed five distinct clusters. The resistant genotypes and susceptible genotypes formed different clusters. The member of cluster 3 was found to be tolerant to terminal heat stress where as members of cluster 2 were found most susceptible to terminal heat stress. From this study genotype BAJ #1/SUP152 was found most tolerant to terminal heat stress. The genotypes belonging to superior cluster could be considered very useful in developing heat tolerant variety and other breeding activities.Int. J. Appl. Sci. Biotechnol. Vol 5(2): 188-193


2015 ◽  
Vol 47 (4) ◽  
pp. 49-63 ◽  
Author(s):  
A.A. Khan ◽  
M.R. Kabir

Abstract Twenty five spring wheat genotypes were evaluated for terminal heat stress tolerance in field environments in the Agro Ecological Zone-11 of Bangladesh, during 2009-2010 cropping season. The experiments were conducted at Wheat Research Centre, Bangladesh Agricultural Research Institute, using randomized block design with three replicates under non-stress (optimum sowing) and stress (late sowing) conditions. Seven selection indices for stress tolerance including mean productivity (MP), geometric mean productivity (GMP), tolerance (TOL), yield index (YI), yield stability index (YSI), stress tolerance index (STI) and stress susceptibility index (SSI) were calculated based on grain yield of wheat under optimum and late sowing conditions. The results revealed significant variations due to genotypes for all characters in two sowing conditions. Principal component analysis revealed that the first PCA explained 0.64 of the variation with MP, GMP, YI and STI. Using MP, GMP, YI and STI, the genotypes G-05 and G-22 were found to be the best genotypes with relatively high yield and suitable for both optimum and late heat stressed conditions. The indices SSI, YSI and TOL could be useful parameters in discriminating the tolerant genotypes (G-12, G-13, and G-14) that might be recommended for heat stressed conditions. It is also concluded from the present studies that biomass, grain filling rate and spikes number m-2 are suitable for selecting the best genotypes under optimum and late sowing conditions because these parameters are highly correlated with MP, GMP, YI and STI. However, high ground cover with long pre heading stage and having high grain filling rate would made a genotype tolerant to late heat to attain a high grain yield in wheat.


2020 ◽  
Vol 71 (19) ◽  
pp. 6015-6031
Author(s):  
Bing Liu ◽  
Leilei Liu ◽  
Senthold Asseng ◽  
Dongzheng Zhang ◽  
Wei Ma ◽  
...  

Abstract Grain yield of wheat and its components are very sensitive to heat stress at the critical growth stages of anthesis and grain filling. We observed negative impacts of heat stress on biomass partitioning and grain growth in environment-controlled phytotron experiments over 4 years, and we quantified relationships between the stress and grain number and potential grain weight at anthesis and during grain filling using process-based heat stress routines. These relationships included reduced grain set under stress at anthesis and decreased potential grain weight under stress during early grain filling. Biomass partitioning to stems and spikes was modified under heat stress based on a source–sink relationship. The integration of our process-based stress routines into the original WheatGrow model significantly enhanced the predictions of the biomass dynamics of the stems and spikes, the grain yield, and the yield components under heat stress. Compared to the original model, the improved version decreased the simulation errors for grain yield, grain number, and grain weight by 73%, 48%, and 49%, respectively, in an evaluation using independent data under heat stress in the phytotron conditions. When tested with data obtained under field conditions, the improved model showed a good ability to reproduce the decreasing dynamics of grain yield and its components with increasing post-anthesis temperatures. Sensitivity analysis showed that the improved model was able to reproduce the responses to various observed heat-stress treatments. These improvements to the crop model will be of significant importance for assessing the effects on crop production of projected increases in heat-stress events under future climate scenarios.


Genetika ◽  
2006 ◽  
Vol 38 (3) ◽  
pp. 175-181 ◽  
Author(s):  
Milka Brdar ◽  
Borislav Kobiljski ◽  
Marija Balalic-Kraljevic

Grain yield of wheat (Triticum aestivum L.) is influenced by number of grains per unit area and grain weight, which is result of grain filling duration and rate. The aim of the study was to investigate the relationships between grain filling parameters in 4 wheat genotypes of different earliness and yield components. Nonlinear regression estimated and observed parameters were analyzed. Rang of estimated parameters corresponds to rang of observed parameters. Stepwise MANOVA indicated that the final grain dry weight, rate and duration of grain filling were important parameters in differentiating among cultivars grain filling curves. The yield was positively correlated with number of grains/m2, grain weight and grain filling rate, and negatively correlated with grain filling duration. Correlation between grain weight and rate of grain filling was positive. Grain filling duration was negatively correlated with grain filling rate and number of grains/m2. The highest yield on three year average had medium late Mironovska 808, by the highest grain weight and grain filling rate and optimal number of grains/2 and grain filling duration.


Author(s):  
Milka Brdar ◽  
Marija Kraljevic-Balalic ◽  
Borislav Kobiljski

Grain yield of wheat is dependent on grain weight, which is the result of grain filling duration and rate. The study was undertaken to examine the relation between grain weight and rate and duration of grain filling in five high-yielding NS wheat cultivars. Stepwise multivariate analysis of nonlinear regression estimated grain filling parameters was used to examine cultivar differences in grain filling. On the basis of three-year average, the highest grain dry weight had cultivar Renesansa, and the lightest grains were measured for cultivar Evropa 90. Stepwise multivariate analysis indicated that all three nonlinear regression estimated parameters (grain weight, rate and duration of grain filling) were equally important in characterizing the grain filling curves of the cultivars studied, although sequence of their significance varied in different years, which is probably caused by different environmental conditions in three years of experiment.


Crop Science ◽  
2013 ◽  
Vol 53 (6) ◽  
pp. 2295-2303 ◽  
Author(s):  
Edmore Gasura ◽  
Peter Setimela ◽  
Richard Edema ◽  
Paul T. Gibson ◽  
Patrick Okori ◽  
...  

2019 ◽  
Vol 71 (2) ◽  
pp. 543-554 ◽  
Author(s):  
Mostafa Abdelrahman ◽  
David J Burritt ◽  
Aarti Gupta ◽  
Hisashi Tsujimoto ◽  
Lam-Son Phan Tran

Abstract Crops such as wheat (Triticum spp.) are predicted to face more frequent exposures to heat stress as a result of climate change. Increasing the yield and sustainability of yield under such stressful conditions has long been a major target of wheat breeding, and this goal is becoming increasingly urgent as the global population increases. Exposure of wheat plants in their reproductive or grain-filling stage to high temperature affects the duration and rate of grain filling, and hence has a negative impact on wheat productivity. Therefore, understanding the plasticity of the response to heat stress that exists between wheat genotypes, especially in source–sink relationships at the reproductive and grain-filling stages, is critical for the selection of germplasm that can maintain high yields under heat stress. A broad understanding of metabolic dynamics and the relationships between metabolism and heat tolerance is required in order to achieve this goal. Here, we review the current literature concerning the effects of heat stress on sink–source relationships in a wide range of wheat genotypes, and highlight the current metabolomic approaches that are used to investigate high temperature responses in wheat.


2020 ◽  
Vol 23 (1) ◽  
pp. 73-79
Author(s):  
T H Ansari ◽  
M Ahmed ◽  
S Akter ◽  
M S Mian ◽  
M A Latif ◽  
...  

Field experiment was carried out in hot and humid summer (Transplanted Aus) season to realize the yield loss of a susceptible rice variety Purbachi inoculated with bacterial blight (BB). Treatments consist of BB inoculations at different crop growth stages like maximum tillering (MT), panicle initiation (PI), booting (Bt), flowering and heading stages differently including a control (no BB inoculation). Disease severity index (DSI) was measured at 14 days after inoculation (DAI) and harvest. Data on 1000-grain-weight and yield was recorded at harvest. Significant variation on DSI was observed among different BB inoculated crop growth stages. MT, PI and Boot stage inoculations showed similar (DSI 7.1-8.0) but higher DSI than flowering and heading stages inoculation (3.2-5.3) even control (0.00) at 14 DAI. However, all the treatments showed similar DSI 9.0 at harvest. Bacterial blight can affect the grain weight to some extent although it was insignificant among the treatments (0.1-4.5%). DSI showed negative correlation with 1000-grain weight (r=-0.77*) and similarly with the yield (r=-0.97**). The yield ranged from 2.4-3.4 t/ha among the treatments. The yield loss was observed 5.8-30.4% in the BB inoculated treatments. MT, PI and Boot stages inoculation affected the yield much resulting 21-30.4% yield loss. It could be concluded that a susceptible variety can be affected with significant yield loss up to 30.4% with severe outbreak of B B. A simple regression equation = 4.09-0.211X( = Yield, X = BB severity score) is suggested for the prediction of yield loss in susceptible variety in summer season. Bangladesh Rice j. 2019, 23(1): 73-79


2017 ◽  
Vol 63 (No. 1) ◽  
pp. 22-28 ◽  
Author(s):  
Wang Yunqi ◽  
Zhang Yinghua ◽  
Wang Zhimin ◽  
Tao Hongbin ◽  
Zhou Shunli ◽  
...  

The North China Plain (NCP) serves as China’s second most important maize production region. Rotary tillage, a popular method used in winter wheat/summer maize systems in the region, has adverse effects on maize production. The current study was conducted to determine whether rotary tillage after subsoiling in the winter wheat season (RS) improves the grain-filling rate and yield of summer maize by decreasing soil bulk density, when compared with rotary tillage (R), in the NCP. The RS treatment decreased soil bulk density and increased soil moisture in the summer maize season when compared with the R treatment. Root number under the RS treatment at 8 collar and silking stages was 22.4−35.3% and 8.0−11.7% greater than under the R treatment, respectively. The RS treatment significantly enhanced the grain-filling rate and grain weight as compared to the R treatment. Yield, thousand grain weight, biomass, and harvest index under the RS treatment were 7.7, 7.2, 2.3 and 5.3% higher than under the R treatment. Thousands grain weight was correlated with soil bulk density and soil moisture after silking. Consequently, the increase in grain weight and yield of summer maize resulted from the decrease in soil bulk density and a consequent increase in soil moisture, root number and grain-filling rate.  


Sign in / Sign up

Export Citation Format

Share Document