Yield and Yield Components Response to Defoliation of Spring Wheat Genotypes with Different Level of Resistance to Helminthosporium Leaf Blight

Breeding for resistance to Helminthosporium leaf blight (HLB) caused by a complex of spot blotch (Cochliobolus sativus) and tan spot (Pyerenophora tritici-repentis Died) of wheat (Triticum aestivum L.) is difficult due to complex nature of resistance, and high influence of environment. This study was conducted to examine whether genotypes having variation in level of resistance and tolerance differ in compensation to loss of leaves. Five spring wheat genotypes with different levels of resistance and tolerance to HLB were grown under irrigated field conditions in randomized complete block design during 2001-2002 and 2002- 2003 wheat-growing season at Rampur, Chitwan, Nepal. Defoliation treatments consist of removal of flag (F), penultimate (F-1), and both F and F-1 leaves were done one day after anthesis. Results showed that defoliation had significant effects on grain yield, biomass yield, thousand-kernel weight (TKW) but not on harvest index, number of grains per spike, kernel per spikelet, and spikelets per spike. All genotypes included in this study showed some degree of compensation for loss of F, F-1, and both F and F-1 leaves, which was found to be variable between years. Removal of flag leaf was compensated by the resistant genotype NL750 for both grain yield and TKW but not for both F and F-1 leaves. Loss of both F and F-1 leaves was better compensated by BL 1473, a stably tolerant genotype in both years. For other genotypes sensitivity to defoliation was found as variable as tolerance to HLB. Key words: Spot blotch, tan spot, defoliation, compensation, flag leaf removal, penultimate leaf removal J. Inst. Agric. Anim. Sci. 26:43-50 (2005)

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Resistance to Helminthosporium leaf blight and agronomic performance of spring wheat genotypes of diverse origins

Euphytica ◽

10.1007/s10681-004-2292-2 ◽

2004 ◽

Vol 139 (1) ◽

pp. 33-44 ◽

Cited By ~ 28

Author(s):

R. C. Sharma ◽

E. Duveiller ◽

S. Gyawali ◽

S. M. Shrestha ◽

N. K. Chaudhary ◽

...

Keyword(s):

Spring Wheat ◽

Leaf Blight ◽

Agronomic Performance ◽

Wheat Genotypes ◽

Helminthosporium Leaf Blight

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Morpho-physiology of wheat genotypes under different sowing dates as affected by Helminthosporium leaf blight and leaf rust in Chiwan, Nepal

Agronomy Journal of Nepal ◽

10.3126/ajn.v3i0.9012 ◽

2013 ◽

Vol 3 ◽

pp. 109-116

Author(s):

SP Neupane ◽

BR Ojha ◽

SK Ghimire ◽

SK Sah ◽

SM Shrestha ◽

...

Keyword(s):

Leaf Rust ◽

Chlorophyll Content ◽

Flag Leaf ◽

Leaf Blight ◽

Animal Science ◽

Wheat Genotypes ◽

Sowing Dates ◽

Rust Severity ◽

Helminthosporium Leaf Blight ◽

Late Sowing

An experiment was conducted at the Agronomy farm of the Institute of Agriculture and Animal Science (IAAS), Rampur, Nepal in 2008/09. The experiment was laid out in factorial design in spit plot arrangement consisting of date of sowing as main factor and wheat genotypes as sub factor. Wheat genotypes were sown in 22 November for normal sowing and 29 December for late sowing condition. These were assessed against Helminthosporium leaf blight and leaf rust severity in a naturally inoculated environment. Result showed that wheat genotypes differed significantly with respect to flag leaf area, flag leaf duration and plant height. Genotype BL-3064 showed the lower decline (624.9 to 615.1) in chlorophyll content whereas RR-21 showed highest decline (471.2 to 360.4) in chlorophyll content from normal to late sowing, possibly contributing to resistant to the disease. The AUDPC value revealed that genotypes BL-3625 and BL-3623 had increased level of resistance due to lower AUDPC value and higher flag leaf duration. The results of this study suggest that genotypes BL-3623, BL-3625, BL-3063 and BL-3064 could be the option in warm and humid regions of Terai condition so far as resistant to Helminthosporium leaf blight and leaf rust are concerned. Agronomy Journal of Nepal (Agron JN) Vol. 3. 2013, Page 109-116 DOI: http://dx.doi.org/10.3126/ajn.v3i0.9012

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Winter Wheat Adaptation to Climate Change in Turkey

Agronomy ◽

10.3390/agronomy11040689 ◽

2021 ◽

Vol 11 (4) ◽

pp. 689

Author(s):

Yuksel Kaya

Keyword(s):

Climate Change ◽

Winter Wheat ◽

Grain Yield ◽

Spring Wheat ◽

Control Treatment ◽

Climate Change Scenarios ◽

Combined Effects ◽

Adaptation To Climate Change ◽

Wheat Genotypes ◽

Plant Characteristics

Climate change scenarios reveal that Turkey’s wheat production area is under the combined effects of heat and drought stresses. The adverse effects of climate change have just begun to be experienced in Turkey’s spring and the winter wheat zones. However, climate change is likely to affect the winter wheat zone more severely. Fortunately, there is a fast, repeatable, reliable and relatively affordable way to predict climate change effects on winter wheat (e.g., testing winter wheat in the spring wheat zone). For this purpose, 36 wheat genotypes in total, consisting of 14 spring and 22 winter types, were tested under the field conditions of the Southeastern Anatolia Region, a representative of the spring wheat zone of Turkey, during the two cropping seasons (2017–2018 and 2019–2020). Simultaneous heat (>30 °C) and drought (<40 mm) stresses occurring in May and June during both growing seasons caused drastic losses in winter wheat grain yield and its components. Declines in plant characteristics of winter wheat genotypes, compared to those of spring wheat genotypes using as a control treatment, were determined as follows: 46.3% in grain yield, 23.7% in harvest index, 30.5% in grains per spike and 19.4% in thousand kernel weight, whereas an increase of 282.2% in spike sterility occurred. On the other hand, no substantial changes were observed in plant height (10 cm longer than that of spring wheat) and on days to heading (25 days more than that of spring wheat) of winter wheat genotypes. In general, taller winter wheat genotypes tended to lodge. Meanwhile, it became impossible to avoid the combined effects of heat and drought stresses during anthesis and grain filling periods because the time to heading of winter wheat genotypes could not be shortened significantly. In conclusion, our research findings showed that many winter wheat genotypes would not successfully adapt to climate change. It was determined that specific plant characteristics such as vernalization requirement, photoperiod sensitivity, long phenological duration (lack of earliness per se) and vulnerability to diseases prevailing in the spring wheat zone, made winter wheat difficult to adapt to climate change. The most important strategic step that can be taken to overcome these challenges is that Turkey’s wheat breeding program objectives should be harmonized with the climate change scenarios.

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Crosses with spelt improve tolerance of South Asian spring wheat to spot blotch, terminal heat stress, and their combination

Scientific Reports ◽

10.1038/s41598-021-85238-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ajeet Kumar Pandey ◽

Vinod Kumar Mishra ◽

Ramesh Chand ◽

Sudhir Navathe ◽

Neeraj Budhlakoti ◽

...

Keyword(s):

Grain Yield ◽

Spring Wheat ◽

High Performance ◽

Recombinant Inbred Lines ◽

Spot Blotch ◽

Spikelet Sterility ◽

Strong Negative Correlation ◽

Terminal Heat Stress ◽

H 26 ◽

The Individual

AbstractSpot blotch and terminal heat are two of the most important stresses for wheat in South Asia. A study was initiated to explore the use of spelt (Triticum spelta) to improve tolerance to these stresses in spring wheat (T. aestivum). We assessed 185 recombinant inbred lines (RILs) from the cross T. spelta (H + 26) × T. aestivum (cv. HUW234), under the individual stresses and their combination. H + 26 showed better tolerance to the single stresses and also their combination; grain yield in RILs was reduced by 21.9%, 27.7% and 39.0% under spot blotch, terminal heat and their combined effect, respectively. However, phenological and plant architectural traits were not affected by spot blotch itself. Multivariate analysis demonstrated a strong negative correlation between spikelet sterility and grain yield under spot blotch, terminal heat and their combination. However, four recombinant lines demonstrated high performance under both stresses and also under their combined stress. The four lines were significantly superior in grain yield and showed significantly lower AUDPC than the better parent. This study demonstrates the potential of spelt wheat in enhancing tolerance to spot blotch and terminal heat stresses. It also provides comprehensive evidence about the expression of yield and phenological traits under these stresses.

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Agronomic Characteristics and Grain Yield of 30 Spring Wheat Genotypes under Drought Stress and Nonstress Conditions

Agronomy Journal ◽

10.2134/agronj2011.0013 ◽

2011 ◽

Vol 103 (6) ◽

pp. 1619-1628 ◽

Cited By ~ 33

Author(s):

Ping Li ◽

Jianli Chen ◽

Pute Wu

Keyword(s):

Drought Stress ◽

Grain Yield ◽

Spring Wheat ◽

Wheat Genotypes ◽

Agronomic Characteristics

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Management of Leaf Blight (Bipolaris sorokiniana) Disease of Wheat with Cultural Practices

Nepal Agriculture Research Journal ◽

10.3126/narj.v7i0.1870 ◽

2009 ◽

Vol 7 ◽

pp. 63-69

Author(s):

PCP Chaurasia ◽

E Duveiller

Keyword(s):

Grain Yield ◽

Plant Height ◽

Cultural Practices ◽

Flag Leaf ◽

Kernel Weight ◽

Leaf Blight ◽

Thousand Kernel Weight ◽

Leaf Infection ◽

Higher Doses ◽

Late Sowing

An experiment was conducted at agronomy farm of Agriculture research Station, Tarahara,Nepal for three consecutive years viz 2000/2001,2001/2002, and 2002/2003 to evaluate theeffects of different cultural practices on leaf blight diseases of wheat caused by Bipolarissorokiniana under terai conditions. The experiment was conducted in factorial RandomizedComplete Block Design with four replications. Four factors, two wheat verities RR-21 andNepal 297,two number of irrigations (two and three irrigations), two doses of Nitrogen fertilizerviz. 60kg N/ha and 120 kg N/ha and two dates of sowing of wheat were examined. Differentyield components, grain yield (kg/plot) and disease severity were recorded to judge the effects ofthese factors on severity of leaf blight of wheat. Nepal Line 297 had significantly less AUDPCbased on flag leaf infection and whole plan as compared to RR-21. Number of irrigations had nosignificant effect on AUDPC, as there was frequent rain during experimental period. Doses ofNitrogen fertilizer had significant effect on AUDPC based on flag leaf infection. It was higher incase of 60 kg N/ha. The third week of November sowing of wheat had lower value of AUDPCas compared to December sowing. Plant height, panicle lengths were highly significantly higherin case of RR-21 as compared to Nepal-297. Thousand kernel weight, and grain yield kg/ha weresignificantly higher in Nepal-297. All agronomic parameters except thousand kernel weight andnumber of tillers/plan were significantly higher in 120kg N/ha. The third week of Novembersowing of wheat had less plant height and panicle length, higher thousand kernel weight andmore grain yield. Leaf blight severity was highly significantly less in case of Nepal-297. Dosesof Nitrogen fertilizer had significant effect on plant height, panicle length, thousand kernelweight, percentage flag leaf infection and AUDPC based on flag leaf infection. Based on theresults of three years of experimentations, it can be concluded that Nepal-297 had less disease,number of irrigations had no effect on disease severity, higher doses of nitrogen fertilizer hadless flag infection and late sowing of wheat also had less disease. Numbers of irrigation's effectswere inconclusive as there were frequent rains during experimentation period. Based on aboveconclusion, it is recommended that growing wheat verity like Nepal-297, use of higher doses ofnitrogen fertilizer and sowing of wheat / first week of Dec help in minimizing the severity of leafblight. However late sowing had lowered grain yield.Key words: AUDPC; culture practices; disease management; leaf blightDOI: 10.3126/narj.v7i0.1870Nepal Agriculture Research Journal Vol.7 2006 pp.63-69

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Evaluation of Spring Wheat Genotypes (Triticum Aestivum L.) for Heat Stress Tolerance Using Different Stress Tolerance Indices

Cercetari Agronomice in Moldova ◽

10.1515/cerce-2015-0004 ◽

2015 ◽

Vol 47 (4) ◽

pp. 49-63 ◽

Cited By ~ 5

Author(s):

A.A. Khan ◽

M.R. Kabir

Keyword(s):

Heat Stress ◽

Grain Yield ◽

Stress Tolerance ◽

Spring Wheat ◽

Grain Filling ◽

Filling Rate ◽

Wheat Genotypes ◽

Grain Filling Rate ◽

Heat Stress Tolerance ◽

Late Sowing

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.

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