Agronomic performance of Indian wheat varieties and genetic stocks known for outstanding chapati quality characteristics

The aim of the present study was to evaluate set of wheat genotypes in one location for their agronomic performance and chapati quality. The cultivars included the tall traditional wheat of the pre-dwarfing era, which were known to excel for chapati quality. This set also included varieties known to have good chapati quality, commercially grown wheats, advanced lines and genetic stocks excelling in one or other quality attribute. All these genotypes developed for different component traits were evaluated along with the recently released high yielding varieties to assess their quality. The mean chapati score of these genotypes revealed that the tall varieties had a distinct edge over others and are the best resource available for this trait. C306 had a high mean chapati score of 8.17 followed by C518, C591 and C273. The released varieties WG357, HD2733 and PBW343 were intermediate in chapati quality whereas the genetic stocks WH1103 and WH712 had lowest score in the group. Among other agronomic traits recorded the traditional varieties were tall and had lower yields than the recently released varieties. The tall varieties had a slightly higher test weight. The environmental conditions and the quantitative nature of the chapati quality did not auger well with the set of genotypes tested however, better and stable performance of the tall traditional varieties. C306 the wheat variety released in 1965 for cultivation has remained the best quality genotype over the years and was also established from this study

Genetic gains in grain yield in wheat (Triticum aestivum L.) cultivars developed from 1965 to 2020 for irrigated production conditions of northwestern plains zone of India

Field trials with 13 landmark wheat cultivars released between 1965 and 2020 were conducted at 15 different locations during 2019–2020 and 2020–2021, providing data from 30 environments. The study of the historical set of spring wheat varieties from the North-Western Plains Zone (NWPZ) of India developed in the last 55 years demonstrated an improvement of grain yield from 3208 to 6275 kg ha−1 or a genetic gain of 1.21% year−1 over long-term check cultivar C306. In real terms, the yield has increased at a rate of 44.14 kg ha−1 year−1. To compare the present genetic gain study, a trend analysis based on historical grain yield data in standard AVT in the zone from 1980 to 2020 was also attempted, which revealed that the percent yield increase was 0.78 per annum. To achieve a higher rate of genetic gain, it requires greater breeding efficiency in the national breeding program through more systematic use of genetic diversity to introduce novel alleles as well as application of new breeding approaches like speed breeding and genomic selection

Harnessing genetic potential of wheat germplasm banks through impact-oriented-prebreeding for future food and nutritional security

The value of exotic wheat genetic resources for accelerating grain yield gains is largely unproven and unrealized. We used next-generation sequencing, together with multi-environment phenotyping, to study the contribution of exotic genomes to 984 three-way-cross-derived (exotic/elite1//elite2) pre-breeding lines (PBLs). Genomic characterization of these lines with haplotype map-based and SNP marker approaches revealed exotic specific imprints of 16.1 to 25.1%, which compares to theoretical expectation of 25%. A rare and favorable haplotype (GT) with 0.4% frequency in gene bank identified on chromosome 6D minimized grain yield (GY) loss under heat stress without GY penalty under irrigated conditions. More specifically, the ‘T’ allele of the haplotype GT originated in Aegilops tauschii and was absent in all elite lines used in study. In silico analysis of the SNP showed hits with a candidate gene coding for isoflavone reductase IRL-like protein in Ae. tauschii. Rare haplotypes were also identified on chromosomes 1A, 6A and 2B effective against abiotic/biotic stresses. Results demonstrate positive contributions of exotic germplasm to PBLs derived from crosses of exotics with CIMMYT’s best elite lines. This is a major impact-oriented pre-breeding effort at CIMMYT, resulting in large-scale development of PBLs for deployment in breeding programs addressing food security under climate change scenarios

Eight loci for resistance to Ustilago tritici race T11 indicated in 20 wheat lines

Loose smut of wheat is a disease of world wide significance. Resistant cultivars constitute a potentially useful and environmentally benign method of controlling this disease. The genetic basis of resistance in 20 wheat genotypes with resistance to Ustilago tritici race T11 was studied in crosses with the widely grown but susceptible Indian cultivar, PBW 343. These lines were also involved in 10 ‘resistant × resistant’ crosses, to infer diversity for resistance genes in this set. All 30 crosses were developed to the F3 stage. Fifteen parents were inferred to carry dominant genes for resistance to race T11. Ten of these resistant lines (ML 521, W 59, W 1616, W 2484, W 2531, W 5915, W 6202, WL 1786, WL 2956 and WL 3450) had resistance controlled by 2 dominant genes acting in a complementary manner whereas in 4 lines (W 4461, W 5100, W 2615 and WL 3951), there was a single dominant gene and in a single genotype, WL 5907, there were 2 dominant genes with duplicate gene action governing the resistance. In lines W 2139, W 3899, W 4985, W 5450 and W 5792 a single recessive gene conferred resistance. Inheritance in two crosses, one derived from a line possessing a single dominant gene and the other from a line possessing a single recessive gene was re-analyzed and successfully confirmed in F5 generation. The segregation of most of the ‘resistant × resistant’ crosses conformed to the inferences drawn about the parents in the ‘resistant × susceptible’ crosses

Investigating the role of high molecular weight glutenin subunits (HMW-GS) protein in end use quality of Indian flat breads

65-73Indian unleavened flat breads more commonly known as chapati are core to existence for two-third of its population. Glutenins and gliadins constitute gluten which gives extensibility and elasticity to the dough, traits which are of great importance in bread making. However, limited studies have been attempted to explore the relationship and functionality of the protein subunits with the quality of the unleavened flat breads. Chapati characterization and molecular analysis was carried on two set of genotypes firstly, different commercial wheat cultivars and genetic stocks for various quality parameters, secondly three back cross derived recombinant populations from the parents with different HMW-GS at Glu 1B locus to associate chapati quality with the glutenin subunits. Significant variation obtained in the genotypes revealed that tall varieties are distinct in quality followed by derivatives of C 306 and C 591 (7.8 for both DI 9 and DI 105). The SDS-PAGE analysis of the high molecular weight glutenin protein revealed that the subunit ‘20’ at Glu1B locus is unique to tall traditional wheats. However, such investigations in the recombinant populations indicated complex inheritance of this trait

Agronomic fortification of rice and wheat grains with zinc for nutritional security

Zinc (Zn) deficiency is the most widespread micronutrient deficiency in crop plants and humans. Low intake of Zn through diet appears to be the major reason for the widespread prevalence of Zn deficiencies in human populations. Application of Zn fertilizer in soil having low Zn increased the grain yield in wheat up to 6.4-50.1%. However, soil Zn application increased the grain yield of rice only up to 7.2-14.8%. Soil having sufficient Zn had no or little effect on grain yield with soil Zn application. The application of foliar Zn with or without propiconazole resulted in significant increases in grain Zn irrespective of soil Zn status. Application of foliar Zn along with propiconazole at earing and milk stages proved beneficial in increasing grain Zn content in both rice and wheat. Hence agronomic biofortification is possible and could be considerably economical if used along with a fungicide depending upon appearance of a disease

Table_1_Application of potassium nitrate and salicylic acid improves grain yield and related traits by delaying leaf senescence in Gpc-B1 carrying advanced wheat genotypes.doc

Grain protein content (GPC) is an important quality trait that effectively modulates end-use quality and nutritional characteristics of wheat flour-based food products. The Gpc-B1 gene is responsible for the higher protein content in wheat grain. In addition to higher GPC, the Gpc-B1 is also generally associated with reduced grain filling period which eventually causes the yield penalty in wheat. The main aim of the present study was to evaluate the effect of foliar application of potassium nitrate (PN) and salicylic acid (SA) on the physiological characteristics of a set of twelve genotypes, including nine isogenic wheat lines carrying the Gpc-B1 gene and three elite wheat varieties with no Gpc-B1 gene, grown at wheat experimental area of the Department of Plant Breeding and Genetics, PAU, Punjab, India. The PN application significantly increased the number of grains per spike (GPS) by 6.42 grains, number of days to maturity (DTM) by 1.03 days, 1000-grain weight (TGW) by 1.97 g and yield per plot (YPP) by 0.2 kg/plot. As a result of PN spray, the flag leaf chlorophyll content was significantly enhanced by 2.35 CCI at anthesis stage and by 1.96 CCI at 10 days after anthesis in all the tested genotypes. Furthermore, the PN application also significantly increased the flag leaf nitrogen content by an average of 0.52% at booting stage and by 0.35% at both anthesis and 10 days after anthesis in all the evaluated genotypes. In addition, the yellow peduncle colour at 30 days after anthesis was also increased by 19.08% while the straw nitrogen content was improved by 0.17% in all the genotypes. The preliminary experiment conducted using SA demonstrated a significant increase in DTM and other yield component traits. The DTM increased by an average of 2.31 days, GPS enhanced by approximately 3.17 grains, TGW improved by 1.13g, and YPP increased by 0.21 kg/plot. The foliar application of PN and SA had no significant effect on GPC itself. The findings of the present study suggests that applications of PN and SA can effectively mitigate the yield penalty associated with Gpc-B1 gene by extending grain filling period in the wheat.</p

An analysis of wheat yield and adaptation in India

Multi-environment wheat trials provide valuable information on the extent of genotype x environment interaction, the stability of genotypes and define and confirm agro-ecological regions through associations among sites. The All India Coordinated Crop Improvement Project on wheat evaluates candidates for release across the wheat growing regions of India. To facilitate this process the wheat area is divided into six agro-ecological zones; the northwestern plains zone (NWPZ), the northeastern plains zone (NEPZ), the central zone (CZ), the peninsular zone (PZ), the northern hills zone (NHZ) and the southern hills zone (SHZ). Factor analytic (FA) models were used to analyze the genotype x environment interaction for yield of 813 wheat genotypes evaluated at 136 locations across the six agro-ecological zones in 1307 individual advanced variety trials between 2008/09 and 2012/13. Genotype x environment interaction was firstly assessed separately within each of the six established agro-ecological zones. Key locations with a high genetic correlation with all other locations within each zone were identified. Predicted genetic values of important cultivars that were represented in a wider range of environments within each zone were estimated and highly stable genotypes were found. Genotype x environment interaction was subsequently assessed across agro-ecological zones. Only those environments where the models accounted for \u3e 99% of the genetic variance were retained for further analysis and two smaller zones (NHZ and SHZ) with little or no genotype congruence with other agro-ecological zones were removed. Thus 476 genotypes from 488 environments were included in the analysis. Fifteen clusters of environments with similar patterns of adaptation were found. These clusters were then characterized based on zonal classification, sowing time, irrigation regime, latitude and year and three regions broadly representing the main wheat growing areas of India were identified. These regions represent a combination of the NWPZ and NEPZ defined by latitude, a central region that combines CZ locations with northern PZ locations and a southern region comprised of southern PZ sites. Further stratification of these zones was then possible based on sowing time and irrigation practice. One cluster of 29 environments had a high average genetic correlation (r = 0.75) with most other environments and production zones. These represent key locations where larger number s of entries might be grown in future seasons as they are the best predictors of yield across cropping zones

An analysis of wheat yield and adaptation in India

Multi-environment wheat trials provide valuable information on the extent of genotype x environment interaction, the stability of genotypes and define and confirm agro-ecological regions through associations among sites. The All India Coordinated Crop Improvement Project on wheat evaluates candidates for release across the wheat growing regions of India. To facilitate this process the wheat area is divided into six agro-ecological zones; the northwestern plains zone (NWPZ), the northeastern plains zone (NEPZ), the central zone (CZ), the peninsular zone (PZ), the northern hills zone (NHZ) and the southern hills zone (SHZ). Factor analytic (FA) models were used to analyze the genotype x environment interaction for yield of 813 wheat genotypes evaluated at 136 locations across the six agro-ecological zones in 1307 individual advanced variety trials between 2008/09 and 2012/13. Genotype x environment interaction was firstly assessed separately within each of the six established agro-ecological zones. Key locations with a high genetic correlation with all other locations within each zone were identified. Predicted genetic values of important cultivars that were represented in a wider range of environments within each zone were estimated and highly stable genotypes were found. Genotype x environment interaction was subsequently assessed across agro-ecological zones. Only those environments where the models accounted for \u3e 99% of the genetic variance were retained for further analysis and two smaller zones (NHZ and SHZ) with little or no genotype congruence with other agro-ecological zones were removed. Thus 476 genotypes from 488 environments were included in the analysis. Fifteen clusters of environments with similar patterns of adaptation were found. These clusters were then characterized based on zonal classification, sowing time, irrigation regime, latitude and year and three regions broadly representing the main wheat growing areas of India were identified. These regions represent a combination of the NWPZ and NEPZ defined by latitude, a central region that combines CZ locations with northern PZ locations and a southern region comprised of southern PZ sites. Further stratification of these zones was then possible based on sowing time and irrigation practice. One cluster of 29 environments had a high average genetic correlation (r = 0.75) with most other environments and production zones. These represent key locations where larger number s of entries might be grown in future seasons as they are the best predictors of yield across cropping zones