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Pusa Basmati 1509 (PB1509) is one of the major foreign-exchange-earning varieties of Basmati rice; it is semi-dwarf and early maturing with exceptional cooking quality and strong aroma. However, it is highly susceptible to various biotic stresses including bacterial blight and blast. Therefore, bacterial blight resistance genes, namely, xa13 + Xa21 and Xa38, and fungal blast resistance genes Pi9 + Pib and Pita were incorporated into the genetic background of recurrent parent (RP) PB1509 using donor parents, namely, Pusa Basmati 1718 (PB1718), Pusa 1927 (P1927), Pusa 1929 (P1929) and Tetep, respectively. Foreground selection was carried out with respective gene-linked markers, stringent phenotypic selection for recurrent parent phenotype, early generation background selection with Simple sequence repeat (SSR) markers, and background analysis at advanced generations with Rice Pan Genome Array comprising 80K SNPs. This has led to the development of Near isogenic lines (NILs), namely, Pusa 3037, Pusa 3054, Pusa 3060 and Pusa 3066 carrying genes xa13 + Xa21, Xa38, Pi9 + Pib and Pita with genomic similarity of 98.25%, 98.92%, 97.38% and 97.69%, respectively, as compared to the RP. Based on GGE-biplot analysis, Pusa 3037-1-44-3-164-20-249-2 carrying xa13 + Xa21, Pusa 3054-2-47-7-166-24-261-3 carrying Xa38, Pusa 3060-3-55-17-157-4-124-1 carrying Pi9 + Pib, and Pusa 3066-4-56-20-159-8-174-1 carrying Pita were identified to be relatively stable and better-performing individuals in the tested environments. Intercrossing between the best BC3F1s has led to the generation of Pusa 3122 (xa13 + Xa21 + Xa38), Pusa 3124 (Xa38 + Pi9 + Pib) and Pusa 3123 (Pi9 + Pib + Pita) with agronomy, grain and cooking quality parameters at par with PB1509. Cultivation of such improved varieties will help farmers reduce the cost of cultivation with decreased pesticide use and improve productivity with ensured safety to consumers.

BackgroundBasmati is a speciality segment in the rice genepool characterised by explicit grain quality. For the want of suitable populations, genome-wide association study (GWAS) in Basmati rice has not been attempted.MaterialsTo address this gap, we have performed a GWAS on a panel of 172 elite Basmati multiparent population comprising of potential restorers and maintainers. Phenotypic data was generated for various agronomic and grain quality traits across seven different environments during two consecutive crop seasons. Based on the observed phenotypic variation, three agronomic traits namely, days to fifty per cent flowering, plant height and panicle length, and three grain quality traits namely, kernel length before cooking, length breadth ratio and kernel length after cooking were subjected to GWAS. Genotyped with 80K SNP array, the population was subjected to principal component analysis to stratify the underlying substructure and subjected to the association analysis using Bayesian-information and Linkage-disequilibrium Iteratively Nested Keyway (BLINK) model.ResultsWe identified 32 unique MTAs including 11 robust MTAs for the agronomic traits and 25 unique MTAs including two robust MTAs for the grain quality traits. Six out of 13 robust MTAs were novel. By genome annotation, six candidate genes associated with the robust MTAs were identified. Further analysis of the allelic combinations of the robust MTAs enabled the identification of superior allelic combinations in the population. This information was utilized in selecting 77 elite Basmati rice genotypes from the panel.ConclusionThis is the first ever GWAS study in Basmati rice which could generate valuable information usable for further breeding through marker assisted selection, including enhancing of heterosis.

The association of parental divergence based on simple sequence repeats (SSR) markers and heterosis in 96 rice (Oryza sativa L) hybrids was investigated for yield and component traits under four environments. Hybrids were derived from four cytoplasmic male sterile (CMS) lines and 24 iso-cytoplasmic restorers (ICR). The genetic distance (GD) and heterosis were significantly correlated for the number of productive tillers per plant (0.537) and panicle length (0.386) in Delhi under early sowing. Under late sowing, negative correlations were also observed (-0.435, -0.401) with pollen fertility percentage. The GD and heterotic performance of hybrids were significantly correlated for panicle length (r=0.35) and number of effective tillers per plant (r=0.51). At Karnal, significant association between GD and hybrid grain yield (0.615) was observed. Besides, insignificant correlations were observed for some other traits at different locations. The non-significant correlations indicated the need of employing trait related functional/ gene based markers as well as using more abundant markers for accurately predicting the hybrid performance.

Solid matrix priming for 24 hr significantly improved seed germination (81.6%) as compared to 12 hr, 36 hr or 48 hr duration. A priming duration of 24 hr gave maximum speed of germination (16.95) while priming duration of 48 hr gave minimum value for speed of germination. No significant differences in speed of germination were found at different temperatures. The interaction effect of priming duration and temperature revealed that solid matrix priming for 24 hr at 20°C is optimum for obtaining maximum speed of germination (17.34). Maximum vigour index I (848.1) was obtained in solid matrix primed seeds for 24 hr duration at 20°C temperature. Osmopriming using PEG 6000 (–1.5MPa) significantly improved seed germination (78%). With increase in priming duration from 2 days to 6 days, there was significant decrease in germination. Osmopriming at –1.0 MPa PEG potential significantly improved speed of germination (7.78) as compared to –0.5 and –1.5MPa potential. The interaction effect of PEG potential and priming duration revealed that osmopriming for 2 days at –1.0 MPa PEG potential gave maximum speed of germination (8.35) over all other treatment combinations. Osmopriming using PEG 6000 (–1.0MPa for 2 days) improved germination by 14.3 percent and field emergence by 13 percent over control. Solid matrix priming for 24 hr at 20oC also improved germination by 13 percent and field emergence by 11.3 percent over control. These results indicate that osmopriming and solid matrix priming can be effectively employed to prime onion seeds for improved field performance.

There is a wealth of knowledge concerning conflict management and its resolution in the workplace, however there is a dearth of information relating to conflict management and its resolution in engineering project management. This paper set out to examine the reality of conflict management in engineering project management in New Zealand. This was achieved through a review of credible literature sources and the completion of a pilot study to gain subject matter expert perspectives. The research suggests that conflicts can be destructive, resulting in anxiety and strong emotional responses leading to reflexive reactions including avoidance, aggression, fight, hostility and a breakdown in communications and relationships. Findings indicate that managing a project structure is synonymous with handling conflict and these disagreements can be detrimental to the success of a project. The initial results suggest that a number of factors act as drivers of conflict in engineering projects in New Zealand. These drivers are: power, personality, group dynamics and organisation culture. The conflict resolution tools cited as being widely used for engineering projects are collaboration and negotiation. The paper also offers recommendations for future research.

Background and Aim: Induced hypotension limits intra-operative blood loss to provide better visibility of the surgical field and diminishes the incidence of major complications during functional endoscopic sinus surgery (FESS). We aimed at comparing nitroglycerine, esmolol and dexmedetomidine for inducing controlled hypotension in patients undergoing FESS. Material and Methods: One hundred and fifty American Society of Anesthesiologists physical status I or II adult patients undergoing FESS under general anesthesia were randomly allocated to three groups of 50 patients each. Group E received esmolol in a loading and maintenance dose of 1 mg/kg over 1 min and 0.5-1.0 mg/kg/h, respectively. Group D received a loading dose of dexmedetomidine 1 μg/kg over 10 min followed by an infusion 0.5-1.0 μg/kg/h, and group N received nitroglycerine infusion at a dose of 0.5-2 μg/kg/min so as to maintain mean arterial pressure (MAP) between 60 and 70 mmHg in all the groups. The visibility of the surgical field was assessed by surgeon using Fromme and Boezaart scoring system. Hemodynamic variables, total intra-operative fentanyl consumption, emergence time and time to first analgesic request were recorded. Any side-effects were noted. The postoperative sedation was assessed using Ramsay Sedation Score. Result: The desired MAP (60-70 mmHg) could be achieved in all the three study groups albeit with titration of study drugs during intra-operative period. No significant intergroup difference was observed in Fromme′s score during the intra-operative period. The mean total dose of fentanyl (μg/kg) used was found to be significantly lower in group D compared to groups E and N (1.2 ± 0.75 vs. 3.6 ± 1.3 and 2.9 ± 1.1 respectively). The mean heart rate was significantly lower in group D compared to groups E and N at all times of measurement (P < 0.05). The MAP was found to be significantly lower in group D compared to groups E and N after infusion of study drugs, after induction, just after intubation and 5 min after intubation (P < 0.05). The Ramsay Sedation Scores were significantly higher in group D (score 3 in 46%) when compared to group E (score 2 in 50%) and group N (score 2 in 54%) (P < 0.001). The emergence time was significantly lower in group E and group N compared to group D. Time to first analgesic request was significantly longer in group D. Conclusion: Dexmedetomidine and esmolol provided better hemodynamic stability and operative field visibility compared to nitroglycerin during FESS. Dexmedetomidine provides an additional benefit of reducing the analgesic requirements and providing postoperative sedation.