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ThesisItem Open Access Pathological and molecular variation in Puccinia triticina the incitant of leaf/brown rust of wheat and host resistance(Punjab Agricultural University, Ludhiana, 2021) Harmandeep Kaur; Jaspal KaurLeaf/brown rust of wheat, caused by Puccinia triticina (Pt), is one of the most important diseases of wheat worldwide. To study the virulence pattern/ diversity of P. triticina, the surveys for leaf rust occurrence were conducted in Punjab during 2018-2021. SBS Nagar (Saroya block) Ludhiana west, Rupnagar (Anandpur sahib) and Gurdaspur were observed as hot spot areas for leaf rust of wheat and disease severity recorded was in the range of 5-40S at different locations. From virulence profiling of the leaf rust infected samples collected from Punjab, it was found that Pt pathotypes 77-5, 77-9, 77-13 (121R60-1,7 ) and 1R 31 are known to occur in Punjab with varied frequencies. Out of which the prevalence of pathotype 77-9 was maximum (62.85%) followed by 121R60-1,7(31.42%). The genetic diversity among Pt isolates was studied using SSR markers which demonstrated that the new pathotype (121R60-1, 7) is more closely related to the pathotype77-9. To know the effectiveness of Lr genes, the leaf rust differentials (Indian and in Thatcher background) and commercial wheat cultivars/ known Lr gene lines were scored against P. triticina infection at four different locations of Punjab (Ludhiana, Gurdaspur, SBS Nagar & Abohar). The lines carrying Lr genes; Lr 9, Lr 19, Lr 24, Lr 25, Lr 28, Lr 29, Lr 32, Lr 42, Lr 45, Lr 47, Lr 52, Lr 57, Lr 58, Lr 76 exhibited resistance against the most prevalent pathotypes (77-5, 77-9 and 121R60-1, 7) of P. triticina in Punjab. One hundread and ninty seven wheat germplasm lines were evaluated at the seedling stage as well as at the adult plant stage against these pathotypes. Based on the seedling reaction test and adult plant response at Ludhiana and Gurdaspur during 2018-2021, it was inferred that thirty six lines showed highly resistant reaction whereas twenty six lines were highly susceptible with AUDPC value >400 and FRS value >40S. DNA of all these test lines was amplified with Lr gene specific markers to identify the gene(s) present in these lines. Based on the molecular data and race specific infection response at seedling as well as at adult plant stage; the leaf rust resistance genes Lr 9, Lr19, Lr24, Lr25, Lr 28, Lr29, Lr32, Lr42, Lr45, Lr47, Lr52, Lr57, Lr58 and Lr76 were postulated in these lines. All stage resistance was imparted by the genes; Lr9, Lr19, Lr24 and Lr28 against prevalent Pt pathotypes in Punjab. The F3 and F5 generation of seven populations were evaluated against P. triticina from 2018-2021 under field conditions at PAU (Ludhiana). The genotypic ratio 1:2:1 and 1:1 for F3 and F5 population respectively fit significantly on the phenotypic data. For gene mapping the resistant and susceptible bulks along with resistant and susceptible parents were genotyped with 90K SNP chip Ilumina array. The SNPs located on the chromosome 5A for population (IC 321853 X HD 3086); 7B for population (IC 549520 X HD 3086); 1B,1D and 6A for population (IC 252609 X HD 3086); 1A, 1D, 3B, 4B and 5A for population (IC 252742 X HD 3086) and 1A, 1B, 2B, 3B and 7A for population (IC 539316 X HD 3086) were selected for designing the KASP markers.ThesisItem Open Access Variations for traits associated with heat tolerance in Indian mustard (Brassica juncea L. Czern and Coss) germplasm(Punjab Agricultural University, Ludhiana, 2021) Harmandeep Kaur; Sharma, PushpThe present investigation was conducted to assess the variations for traits associated with heat tolerance in Indian mustard (Brassica juncea L. Czern and Coss) germplasm at seedling and terminal stages. Field experiment was conducted in rabi season (2017-18) at Punjab Agricultural University, Ludhiana at two dates of sowing i.e. timely sown and late sown conditions. Heat stress at early seedling stage lead to seedling mortality thus affecting plant population and seed yield Terminal heat stress caused by delayed sowing shortened the phenological durations to variable extent, significantly reduced the physiological traits like photosynthetic pigments, SPAD value (7.2%), RWC (8%), LWR (17.2%) while increased the RSD (23.9%), WSD (23.9%), LWL (30.4%), membrane injury (6.9%) and MDA (57.2%). Antioxidative enzymes like SOD (40.4%), CAT (69.3%) and POX (76.7%) were upregulated along with other biomolecules like ascorbic acid (65.4%) which increased significantly for the protection against the late sowing/ stressful environment. Total soluble sugars decreased by 36.8%, reducing sugars by 44.7% and non-reducing sugars by 32.4% with delayed planting. Growth parameters, yield attributes and seed yield were reduced significantly with late sowing as compared to optimum sowing date. However, variations existed within genotypes for different studied traits. Seed yield under late sown condition had positive and significant correlation with siliquing duration (r= 0.600*) and reproductive phase (r= 0.558*) whereas, negative with flowering completion (r= -0.573*) and siliqua initiation (r= -0.519*). Biological yield had significant association with seed yield under timely sown (r= 0.774**) and late sown (r= 0.841**) conditions. Similarly, biological yield had strong relationship with seed yield both under timely sown (R2= 0.5985) and late sown (R2= 0.7075) conditions. Genotype IAN was rated heat tolerant with seedling mortality ≤30%, seed yield reduction ≤30%, HTI (≥0.5), HSI (≤1.0), YSI (≥0.71), lesser decline in the physiological traits added with relatively higher antioxidative enzymes.ThesisItem Open Access Productivity assessment and molecular marker cataloguing for vernalization and photoperiod genes in winter x spring wheat derivatives(Punjab Agricultural University, Ludhiana, 2020) Harmandeep Kaur; Sohu, V.S.It is imperative to provide economic and ecological alternative to burning for managing the rice residues. In-situ management of rice residue (retention or incorporation) has potential to solve this issue. It is hypothesized that if wheat sowing is done in rice residue than an early planting needs to be followed which will utilize the residual soil moisture of rice along with forgoing the pre-sowing irrigation. The rice stubble will act as mulch and conserve the moisture as well as control weeds. This solution however, requires a new ecology for wheat crop. We need such genotype of wheat that can be planted early and having both early and terminal heat tolerance while flowering at the appropriate time. For this, we need optimum combination of Vrn and Ppd genes that regulate flowering time in wheat cultivar. At PAU we have European winter wheat germplasm that was hybridized with local spring wheat cultivars. BC1F5 lines (480 progenies) developed, were used in this study. During the first year the lines were evaluated for key yield traits and were also haplotyped for the vernalization and photoperiod allele. The Vrn-A1, Vrn-B1, Vrn-D1, Ppd-A1 and Ppd-D1 alleles were amplified using polymerase chain reaction. The final 60 selected progenies have the haplotypes viz, vaaa (17), vava (15), vaab (1), vvaa (2), vvva (24) and one having vvvb. During 2018-19 evaluation of lines with known allelic combinations of Vrn and Ppd genes was undertaken under two sowing times early (15-20 October 2018) and timely (25-30 October 2018). The highest yield was obtained under happy seeder early sown followed by PAU Timely sown. Happy seeder timely sown (HSTS) shown reduced yield followed by Gurdaspur early sown (GDPES) and Gurdaspur timely sown (GDPTS). The location interaction clearly indicated that the set of germplasm tested had a distinct advantage under Happy seeder conditions.ThesisItem Restricted A STUDY OF PERCEPTION INVOLVED IN IMPLEMENTING INTERNATIONAL FINANCIAL REPORTING STANDARDS (IFRS) AND IT’S COMPARISON WITH INDIAN ACCOUNTING STANDARDS (IAS)(PAU Ludhiana, 2011) Harmandeep Kaur; Sandeep, KapurIFRS is regarded as the uniform reporting language for all concerns and the nations. The study was conducted to compare the existing Indian Accounting Standards with the IFRS. Secondly, study was done to see the perception involved in implementation of IFRS. The practicing chartered accountants, academicians and managers were the respondents of the study. The sample consisted of 30 practicing chartered accountants, 15 managers and 5 academicians. The results of the study revealed that IFRS and the Indian Accounting Standards has a greater degree of variation with respect to disclosures, financial statements, transparency, uniformity and consistency. The respondents perceived that in terms of implementing IFRS; sufficient communication patterns, training programs and management skills were required. It was found that the lack of resources and cost of training the employees were the major bottlenecks in implementing the IFRSThesisItem Open Access Interactive effect of deep tillage and irrigation regimes on crop growth and yield of kharif maize(Punjab Agricultural University, Ludhiana, 2016) Harmandeep Kaur; Meharban SinghDeep tillage responses in maize on coarse textured soils are reported to be related with improvement in root growth and plant water status. In a field study on sandy loam soil at the research farm of Department of Soil Science during Kharif 2015; combinations of two tillage systems i.e. conventional tillage (CT) and deep tillage (DT) and two irrigation regimes i.e. irrigation water/pan evaporation ratios of 0.5 (I1) and 1.0 (I2) were evaluated on two maize hybrids i.e. PMH1 (long duration) and PMH2 (short duration). DT with sub soiler loosened soil in chisel furrow up to 35-45 cm depth. Comparatively higher bulk density i.e. 1.66 and 1.69 Mg m-3 was observed in 15.0-22.5 and 22.5-30.0 cm soil layers, in CT and the reduction in bulk density with DT was maximum in these layers. The penetration resistance (PR) was also lower with DT than with CT; however the magnitude of decrease varied with soil depth and position of measurement. Root length density (RLD) at 70 DAS, was higher under DT than CT in the 15-90 cm depth and increased irrigation level produced higher RLD, under DT but not under CT. Root length index (RLI) in the 90 cm soil profile, did not vary with irrigation level but DT increased RLI. Both leaf area index and plant height were generally higher under DT than CT and with I2 over I1, but the effect was significant only for DT. PMH2 was significantly shorter in plant height than PMH1 at all the growth stages. Leaf water potential (LWP) at 66 DAS was significantly higher with DT and with I2 in both the hybrids. Increase in LWP with I2 over I1 was significant under CT only. Soil temperatures in general were lowered with irrigation & DT and were slightly lower in PMH1 than PMH2. Both DT and higher irrigation caused higher chlorophyll content, but effect was significant for DT only. Fifty percent tassel stage under DT as compared to CT, was 3.3 & 1.8 days earlier in PMH1 and 4.8 & 7.2 days earlier in PMH2; in I1 & I2 treatments respectively. Both grain and biological yields (grain plus stover) were significantly higher with DT over CT and with I2 over I1 in both the hybrids. PMH1 as compared to PMH2, produced significantly higher grain (12.5 %) and biological (17.8 %) yields. Percent increase in grain yield with DT over CT, for I1 & I2 respectively, was 33.8 & 30.6 in PMH1 and 24.5 & 16.8 in PMH2. Significant interaction was observed between tillage and cultivar for biological yield only. Harvest index did not vary significantly with tillage and irrigation treatments, but hundred grain weight varied significantly with tillage and cultivar. Soil profile water use was higher in DT over CT; by 43.5 & 24.5 mm in PMH1 and 31.6 & 22.6 mm in PMH2; for I1 & I2 irrigation regimes respectively. Averaged over other two treatments; water productivity (kg ha-1 mm-1) was higher in DT over CT by 21.2 %; in I1 over I2 by 6.0 % and in PMH1 over PMH2 by 10.9 %.ThesisItem Restricted Virulence spectrum of puccinia striiformis f. Sp. Tritici in Punjab(Punjab Agricultural University, Ludhiana, 2017) Harmandeep Kaur; Jaspal KaurStripe rust of wheat, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most devastating disease of wheat worldwide. The purpose of this research was to survey Punjab fields to determine the prevalence of stripe rust, characterize the race structure of Pst on the basis of virulence and to know the molecular diversity of the pathogen population. During the year 2014-2015 disease severity was in the range of 5-60 per cent in Rupnagar while 10-20 per cent in other areas. During the crop season 2015-16 maximum disease severity was in the month of December i.e.10-40 per cent in Rupnagar followed by traces to 40 per cent in SBS Nagar and 20 per cent in Hoshiarpur, Gurdaspur, Fatehgarh Sahib and 10 per cent in Ludhiana, Patiala on different cultivars. Race characterization was done by inoculating differential lines carrying known resistance genes along with 15 supplemental cultivars with 12 Pst isolates collected from hot spot areas of Punjab along with pathotypes 78S84, 46S119 and 110S119 obtained from IIWBR, Regional station, Flowerdale, Shimla. On the basis of their reaction on differentials, 3 races namely 46S119, 110S119 and 238S119 were identified. Genes Yr1, Yr5, Yr10 conditioned resistance against all isolates tested on differentials and all isolates were virulent on Yr2, Yr3, Yr4, Yr6, Yr7, Yr8, Yr9. Variation for virulence was observed among isolates on YrSD, YrSU and Yr9+. Out of fifteen (15) supplement genotypes, six (6) genotypes namely PBW729 (Yr15), PBW730 (Yr10), BWL2763 (Yr15), BWL3277 (Yr5), BWL3558 (Yr5), BWL4405 (Yr10) having resistance genes Yr5, Yr10, Yr15 were recorded highly resistant. PBW 343 showed ‘highly susceptible’ reaction against all isolates of Pst with maximum disease severity of 80 per cent and minimum incubation period of 8-9 days. Molecular diversity (based on SSR polymorphism) showed that isolates collected from Punjab were more diverse than isolates obtained from IIWBR, Regional station, Flowerdale, Shimla. On the basis of SSR primers (SOB, PAU, Ludhiana) result revealed that previous year isolates were genetically different than current isolates.
