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From roughly 1930 to 1950, newsreel theaters played important roles in urban and film cultures. These small (200- to 600-seat) theaters showed hour-long loops of news that patrons could drop into from morning to midnight. Some aspects of the newsreel theater experience extended the rituals of nickelodeon spectatorship of earlier decades, and others predated the post–World War II development of television news consumption. Newsreel theaters allowed patrons to pass the time watching motion picture news, and they became politically charged spaces offering ways for people to watch and react vocally to the news in public as members of groups. [ABSTRACT FROM AUTHOR]

The impact of heat stress coinciding with reproductive stages in winter canola was studied using walk‐in controlled environment chambers and field‐based tents. Six different cultivars (46W94, Edimax CL, Mercedes, Popular, DKW44‐10 and DKW46‐15) were used in both the experiments following a split‐plot design. Under controlled environment chambers, all six cultivars were exposed to HDT (day/night; 34/15°C), HNT (23/20°C), HDNT (34/20°C) and control (23/15°C) conditions for 14 days coinciding with flowering. Under field conditions, custom built 'heat tents' were used to impose heat stress starting seven days after 50% of flowering till maturity. The results demonstrated that HDT and HDNT induced significant impact on floral morphology, extreme levels of floral sterility and complete yield loss with two weeks of stress exposure during flowering. However, biomass, seed weight and oil concentration at maturity were either significantly increased or unchanged which demonstrated significant post‐stress phenotypic plasticity in canola to overcome damage caused by short episode of HDT and HDNT during flowering. The long duration heat stress under field conditions recorded significant decrease in yield parameters and oil concentration in the canola cultivars. Incorporating greater post‐stress phenotypic plasticity will help develop canola as an ideal alternative crop under future climates associated with enhanced frequency of short heat stress episodes coinciding with critical reproductive stages. [ABSTRACT FROM AUTHOR]

The article comments on the paper "Labor Reporting and Its Critics in the CIO Years," by Philip Glende on topics including the history of labor reporting, the active opposition of daily newspapers to labor, and the creation of public perception of labor.

This article reassessesThe People's Choiceby Paul Lazarsfeld, Bernard Berelson, and Hazel Gaudet, one of the foundations of communication and voting behavior research. As with most classics, which are often cited but seldom read, we believe this book has much to teach contemporary social scientists. We return to the original context of the research and use voting data from the period with three broad goals: (a) to find ideas and lessons from this work that generally have been overlooked, (b) to suggest new ways of applying these ideas, and (c) to encourage scholars to engage more with this seminal work to understand ideas that are often overlooked when a complex piece of research is reduced to a brief discussion or passing citation. [ABSTRACT FROM AUTHOR]

In the early twentieth century, American newspapers enjoyed high circulations while presenting readers with diverse and plentiful content. After 1920, radio broadcasting made even more information available for public consumption, giving audience members an abundant range of media choices. During a time of plenty for readers and listeners, companies in the business of media struggled with the opposite problem: scarcity. As the amount of media content proliferated, the practical ability to disseminate it was determined by the access to scarce resources, and this was true for both radio broadcasting and newspaper publishing. In many respects, the history of the American mass media in the early twentieth century might best be told as a tale of two scarcities, one—the electromagnetic spectrum—defined by absolute limits and the other—the newsprint—defined by access to markets for a particular material, the supply of which often fluctuated in availability and price. [ABSTRACT FROM PUBLISHER]

Purpose: To improve the cost efficiency of the imaging evaluation of clinically suspected pheochromocytoma by using 24-hour fractionated urine metanephrine (FUM) results. Methods: A retrospective review of 1-123 meta-iodo-benzy1-guanidine single photon emission tomography (SPECT) computed tomography (CT) studies performed at our institution between January 2007 and February 2011 for clinically suspected pheochromocytoma was performed. SPECT-CT results from 70 patients were compared with results from 24-hour FUM analysis (within 2 months of SPECT-CT) and with relevant CT or magnetic resonance imaging studies (within 6 months of SPECT-CT). An imaging algorithm was developed to maximize cost efficiency without altering the final imaging interpretation. Actual imaging costs for the studied cohort were compared with the expected costs if this algorithm had been applied. Results: If the 24-hour FUMs were normal, then all the SPECT-CT studies were negative (16/70). Eighty-seven percent of patients with abnormal total metanephrine had a positive SPECT-CT. If the total metanephrine was normal but 1 or more of the metanephrine fractions were abnormal, then 39%-58% of the SPECT-CT studies were positive. Within this subgroup, none had a positive SPECT-CT if a CT or magnetic resonance image was negative or benign. The actual imaging costs averaged CADS2833.19 per patient for this cohort. Applying a streamlined imaging algorithm guided by 24-hour FUM analysis would result in an average imaging cost of CADS 1225.97 per patient without an expected change in the final imaging impression. Conclusion: By using 24-hour FUM results to streamline imaging, considerable cost savings per patient (56.7%) can be attained without a change in the final overall imaging interpretation. [ABSTRACT FROM AUTHOR]

The article analyzes the history of the newspaper industry and attributes the current crisis to managerial short-run decisions from 1985 to 2004. It attributes reduced local market growth to declining circulation and maximized advertising prices. Reasons cited for the decline in circulation include clustering or buying newspapers within the same region to cut costs and reduce competition, lower quality newspapers because of lack of investment in the newsroom and rising costs of advertising.

Purpose: To assess ultrasound intrascan variability and the potential error rate of serial ultrasounds in the diagnosis of deep venous thrombosis in children. Methods: A retrospective cohort review of imaging results of children having at least 3 serial ultrasound examinations of the same region within a 2-month period. The results were interpreted as either (1) inadequately visualized or (2) the absence or presence of deep venous thrombosis, and were categorized by location. Serial imaging findings then were further categorized based on results and clinical information. Results: Sixty-four patients and 157 vessel segments were included in the study. Deep venous thrombosis was documented in 58 patients. Concordant results were observed in 26 patients (40.1%), clot resolution in 17 patients (26.6%), clot formation in 12 patients (18.8%), and discordant results in 9 patients (14%). Twenty-one of 64 patients (32.8%) had at least 1 vessel inadequately imaged. Conclusions: The inconsistency of serial ultrasound results in up to 25% of patients calls attention to the potential inaccuracy of ultrasound for diagnosis and follow-up of deep venous thrombosis in children. The high proportion of patients with at least 1 inadequately visualized vessel also highlights the limitation of ultrasound in the diagnosis of pediatric deep venous thrombosis. [ABSTRACT FROM AUTHOR]

The article looks at mass media in the U.S. in the context of business history, specifically the challenges faced by newspapers as electronic media advances. The author details the history of radio broadcasting by newspapers in the U.S. beginning in August 1920. The aspirations of newspaper tycoon William Randolph Hearst to own radio stations in every city where he owned a newspaper are mentioned. The article addresses the use of multimedia brand promotion. The "Amos 'n' Andy" radio program and its advertisements are talked about. The article also discusses the business model of the "Chicago Tribune" newspaper.

This article reports that in early 1968, Bernard Jacobs, the owner and founder of Chicago classical music radio station WFMT, sold his station to WGN Continental FM Corp., a subsidiary of the Chicago Tribune. Despite the fact that the Tribune claimed that it would make no changes to the station's programming or management, the sale was profoundly disconcerting to many loyal listeners, a number of whom wrote letters to the federal government opposing the sale and asking it to intervene. Listener Marjorie Newsome wrote that WFMT's audience was composed largely of persons or a more progressive bent, and was a group that possessed a certain level of judgment, sophistication, and discrimination, with respect to its listening preferences. Four years later, Chicago's other major classical music radio station, WEFM, was put up for sale by the Zenith Corp., the company that had owned and operated the station for more than 30 years. Claiming that the station was losing large amounts of money, Zenith sold it to General Cinema Corp. (GCC), a Boston-based entertainment conglomerate, and GCC announced that it would change the station's format from classical to pop music.

Presents information on a study that examined a proposed single-switch topology that ensures safe reverse and forward recovery through an improved gate drive arrangement. Switch topologies; Device testing circuit; Experimental results.

Investigates the specificity and extent of crosslink formation within an oligomeric duplex as a function of 5-(omega-(omega-haloacylamido)alkyl)-2'-deoxyuridine under conditions approximating the physiologic environment. Site and extent of crosslinking; Regiospecificity of alkylation.

A diverse population (429 member) of canola (Brassica napus L.) consisting primarily of winter biotypes was assembled and used in genome-wide association studies. Genotype by sequencing analysis of the population identified and mapped 290,972 high-quality markers ranging from 18.5 to 82.4% missing markers per line and an average of 36.8%. After interpolation, 251,575 high-quality markers remained. After filtering for markers with low minor allele counts (count > 5), we were left with 190,375 markers. The average distance between these markers is 4463 bases with a median of 69 and a range from 1 to 281,248 bases. The heterozygosity among the imputed population ranges from 0.9 to 11.0% with an average of 5.4%. The filtered and imputed dataset was used to determine population structure and kinship, which indicated that the population had minimal structure with the best K value of 2–3. These results also indicated that the majority of the population has substantial sequence from a single population with sub-clusters of, and admixtures with, a very small number of other populations. Analysis of chromosomal linkage disequilibrium decay ranged from ~7 Kb for chromosome A01 to ~68 Kb for chromosome C01. Local linkage decay rates determined for all 500 kb windows with a 10kb sliding step indicated a wide range of linkage disequilibrium decay rates, indicating numerous crossover hotspots within this population, and provide a resource for determining the likely limits of linkage disequilibrium from any given marker in which to identify candidate genes. This population and the resources provided here should serve as helpful tools for investigating genetics in winter canola. [ABSTRACT FROM AUTHOR]

Reports on the case of a 56-year-old woman with a malignant variant of symptomatic cough headache who developed pneumocephalus (PC) and subsequently, pneumococcal meningitis, arising from infected paranasal sinuses. Prompt institution of antibiotics after diagnostic lumbar puncture resulted in the resolution of PC within 24 hours; Medical history; Therapeutics.

Winter canola (Brassica napus L.) production has increased in the Great Plains as producers seek a rotational and alternative crop to winter wheat (Triticum aestivum L). However, limited information is available if canola could be used for dual‐purpose without significantly affecting grain yield. The objectives of this study were to (a) investigate dual‐purpose potential and (b) impact of companion crops on growth, survival, biomass, and grain yield of canola. The study was conducted in 2011 and 2012 at Garden City, KS. The experimental design of the study was a randomized complete block design with split‐plot arrangement. Main plot treatments were a factorial of canola cultivars (Griffin or Wichita) and companion crop treatments (none, spring triticale [× Triticosecale Wittm. ex A. Camus], winter triticale, radish [Raphanus raphanistrum subsp. sativus (L.) Domin], and turnip [Brassica rapa var. rapa L.]), and the split‐plot treatments were single‐purpose (grain only) or dual‐purpose (grain and forage) management. Averaged across cultivars and years, grain yield was 70% greater when canola was used for single‐purpose (grain‐only) compared with dual‐purpose. Griffin grain yield tended to be relatively greater than Wichita in dual‐purpose use. Averaged across the two years, turnip as a companion crop decreased canola yield by 38% but resulted in greater forage accumulation. In conclusion, dual‐purpose canola has a grain yield penalty, but effects may vary by cultivar. Companion cropping did not benefit canola and in some cases negatively affected grain yield. When grain production is the primary objective, both companion cropping and forage use should be avoided. [ABSTRACT FROM AUTHOR]

Winter canola (Brassica napus L.) is highly sensitive to increasing temperatures during the reproductive and pod‐filling stages. Although the impact of high day‐time temperature stress on yield and quality has been documented in canola, similar information under high night‐time temperature (HNT) stress is not available. Using six hybrids and four open‐pollinated cultivars, we observed a marked shift in peak flowering towards earlier, cooler hours of the morning under HNT. Averaged across two independent experiments, the photochemical efficiency of photosystem II was significantly decreased (3%), with a significant increase in thylakoid membrane damage (13%) in the leaves of susceptible cultivars under HNT stress. Similarly, the susceptible cultivars also recorded significant reduction in biomass (34%), pod number (22%), pod weight (37%) and total seed weight (40%) per plant while the same set of agronomic traits were not affected among the tolerant cultivars. Quantitative impact of heat stress was confirmed with increased sensitivity to HNT exposure from gametogenesis until maturity resulting in a significantly higher yield loss compared to stress exposure from post‐flowering till maturity. HNT significantly decreased oil concentration, but increased protein concentration and saturated fatty acid levels in seeds of the susceptible cultivars. However, HNT had no impact on the unsaturated fatty acids in both hybrids and the open‐pollinated cultivars. Breeding targets based on fatty acid composition for enhancing canola seed quality may not be easily amenable due to the inconsistency documented with the compositional changes under heat stress. In summary, our findings conclude that canola hybrids are better suited to regions experiencing heat stress, compared to open‐pollinated cultivars, indicating the possibility of a complete shift to hybrid canola cultivation under predicted hotter climates in the future. [ABSTRACT FROM AUTHOR]

Canola (Brassica napus L.) is a major oilseed crop for edible and industrial uses. Climate change, characterized by extreme heat and drought conditions, can affect canola seed yield and quality (protein and oil), restricting grower capacity to keep pace with growing demand. However, estimating the influence of future climate on such complex traits is challenging due to biophysical interactions and crop adaptations to abiotic stresses. Current scientific literature reports contrasting impacts on the effect of heat and drought for canola productivity, mainly linked to changes in magnitude and duration of the stress. To better understand how drought and heat affect canola seed yield and quality (mainly protein and oil), a meta-analysis was executed to compile a total of 39 papers (1794 observations). The aims of this research were to i) quantify the impact of different timing and duration of heat and drought stresses on canola seed yield, oil yield, and seed quality (oil and protein concentration), and ii) study the effect of short-term stresses on seed quality, yield and its components (seed number and seed weight). This review study highlighted the magnitude and direction of overall and different stress impacts on canola; and some of the main limitations in the current scientific literature. Briefly, the main outcomes of this review highlighted that i) early heat stress(before end of flowering) had the largest impact on canola seed yield, as a short stress, ii) drought caused greatest yield impact when imposed for a long duration during flowering or a shorter duration during pod setting, and iii) short stresses had large impacts on seed oil concentration mainly during pod setting. More studies with standard stress levels and detailed information of abiotic stresses on reproductive growth stages are needed. This meta-analysis provides critical information for crop management, guiding development of cultivars linked to tolerance to abiotic stresses for breeding programs, and the future direction of canola adoption and production. • Contrasting heat and drought impacts on canola/rapeseed were reported in the literature. • This meta-analysis dissected abiotic stress timing and duration. • Highest negative impacts on yield were observed with stresses imposed before the end of flowering. • Seed oil and protein concentration were affected following abiotic short stresses during pod setting. [ABSTRACT FROM AUTHOR]

Including winter canola (Brassica napus L.) crop into cereal-based crop rotations can diversify the current agricultural systems in the United States (US). In addition, canola can help to satisfy market demand for plant-based edible oil, thus better understanding of oil productivity of canola in the US production areas is relevant for further study. Canola seed oil concentration is a function of the genotype (G), environment (E), management (M), and their interaction (G × E × M). The overall aim of this research study was to identify suitable production environments with increased canola seed oil concentration and opportunities to increase cropland area in the US. The objectives of this research were: i) characterize the environmental variability of seed oil concentration in the National Winter Canola Variety Trials (NWCVT), ii) identify geographical regions and states within the continental US with potential for production of winter canola with high seed oil concentration and the link with yield, and iii) explore the potential development of varieties with stable high seed oil concentration and high yield. In this study, the E component accounted for 75% of the total variation in seed oil concentration, with the G factor only explaining 8%. Overall, seed oil concentration averaged 398 g kg-1 but ranged from 311 to 461 g kg-1. The US Midwest and Great Plains regions were shown to have a greater frequency of medium (> 389 g kg-1) and high canola seed oil concentration (> 411 g kg-1). Genotypic variation for both seed oil concentration and yield was found with an opportunity to achieve high oil and yield under varying environments. Our findings suggests that there is significant potential to further expand the area of canola cropland to increase oil productivity and focus should be on breeding high yielding varieties with stable high seed oil concentration. • Environment explained most of the oil concentration variability in winter canola. • Precipitation and photothermal quotient explain the oil concentration variability. • Large winter canola production area with potential for high oil concentration in US. • Potential to develop varieties with stable high seed oil concentration and yield. [ABSTRACT FROM AUTHOR]

Successful winter canola (Brassica napus L.) production creates diversity and provides crop rotation alternatives for producers. Stand establishment and winter survival are among the main determinants of success in winter canola production. The objective of this research was to investigate the impact of environment, crop management, genetics and their interactions on canola stand establishment, survival, yield, and oil and protein content. Two datasets were analyzed: results from the National Winter Canola Variety Trials conducted from 2003 to 2012 and data from experiments conducted for 3 yr (2010-2012) in Manhattan, KS, to assess the impact of planting date, tillage, and cultivar on canola yield and survival. Canola has the potential to yield up to 7 Mg ha-1; however, actual yields were usually in the range of 0 to 4 Mg ha-1. The average oil content of canola seeds was 40%, but the potential extended to 47%. Environment, defined as a combination of year and location, was responsible for the majority of variation in yield, oil content, stand establishment, and survival of winter canola. Planting in mid to late August and early September benefited yield most of the time compared with planting late in September or October in the Great Plains and Midwestern United States. Only with extremely early or late planting did tillage improve winter survival and yield compared with no-till. Crown height of canola was greater in no-till treatments compared with conventional tillage treatments, but a significant relationship was not observed between crown height and winter survival or yield. Cultivars differed significantly in yield, survival, and crown height, but no cultivars were consistently superior in no-till conditions or with plantings outside of the recommended time frame. [ABSTRACT FROM AUTHOR]

While generally understood as an individual-level effect, we argue that reinforcement effects—or the strengthening of existing party loyalties through media exposure—might also play a role in shaping aggregate-level outcomes. Looking across eight presidential elections from 1900 to 1928, this study provides evidence that partisan newspaper circulation was significantly linked to two-party vote share at the county level. Counties with higher circulation rates of Republican dailies had a smaller percentage of votes cast for the Democratic presidential candidate, while a weaker positive association was found between the circulation of Democratic leaning dailies and Democratic vote in non-Southern counties. Some variance in this effect was observed across elections, with some evidence suggesting a weaker association between circulation and vote share as newspapers moved away from overtly partisan content toward a more professional tone. Further, some of the relationships were reciprocal with votes influencing partisan circulation. Results suggest that greater attention be given to the role of the political media environment and how citizens engage with it when understanding macro-level political outcomes. [ABSTRACT FROM AUTHOR]

• Canola winter survival was linked to minimum temperature and its fluctuations • High probability of canola winter survival reported south latitude 35°N in US • There is potential to develop canola genotypes with tolerance to winter-kill • Semi-tolerant canola types for winter survival are already broadly used in US • Canola winter survival response driven by air temperatures and windchill The introduction of winter canola (Brassica napus L.) into rotations with winter wheat (Triticum aestivum L.) in the United States (US) revealed economic and agronomic benefits as well as improved weed and pest control. Canola stand establishment during the fall and plant survival over the winter are critical to the success of this crop. The environment plays a key role influencing survival, but in-depth evaluation of meteorological factors has not been conducted. This research study aimed to: i) identify meteorological factors underpinning winter canola survival, ii) build probabilistic response models based on historical meteorological data for different severities of winter kill across the US, and iii) define areas of adaptation of current germplasm. A winter survival dataset was compiled from the National Winter Canola Variety Trials from 2003 until 2018 (190 site-years) and auxiliary meteorological data over the last 40 years. A regression tree analysis indicated that meteorological variables related to minimum temperature, fluctuating temperatures above and below 0°C, and windchill during the cold period were the main factors accounting for winter kill. Cold periods across all site-years were classified into three clusters: cold periods with high (96%), medium (70%), and low (28%) average plant winter survival. For 94 US sites, the probabilities of these conditions were calculated and summarized in a map that defined areas of adaptation: a large area south of 35° N latitude for the US was identified with greater potential for overwintering success. Based on the response under multiple meteorological conditions, four distinct genotype survival groups were identified (tolerant, semi-tolerant, semi-susceptible, and susceptible). Groups with a greater number of genotypes differ in the impact of meteorological conditions on survival for the medium cluster. In regions with more favorable conditions for overwintering success, farmers may be open to introducing this crop to diversify their farming system. [ABSTRACT FROM AUTHOR]

Winter canola generally produces greater yields than spring canola. However, its range is limited due to its inability to withstand the harsh winter conditions that occur in many northern regions of the U.S.A. To identify loci associated with freezing tolerance in canola, we conducted a genome-wide association study (GWAS) using a genotyped diversity panel containing 399 accessions consisting primarily of winter canola. One-month-old greenhouse grown plants were subsequently cold-acclimated for two months in an environmental growth chamber prior to phenotyping for freezing survival using a visual damage scale and chlorophyll fluorescence (Fv/Fo). There was reasonable correlation observed between visual damage and chlorophyll fluorescence ratings among the top associated loci; the results indicated that some loci contributed to both freezing damage/tolerance and photosynthetic efficiency. The resulting numerical values for phenotypes were used for association analyses with the identified SNPs. Thirteen significant markers were identified on nine chromosomes for the phenotypes scored, with several showing significance for multiple phenotypes. Twenty-five candidate genes were identified as previously associated with freezing tolerance, photosynthesis, or cold-responsive in canola or Arabidopsis. [ABSTRACT FROM AUTHOR]

Canola (Brassica napus L. cv. 'Canola') production has both economic and agronomic advantages. The objectives of this review were to summarize the key management factors determining crop productivity and to propose plausible pathways to narrow the gap between actual and potential yield. A synthesis study was conducted on data available from performance trials and by reviewing >100 reports in peerreviewed journals, extension publications, and websites. The main outcomes obtained from this synthesis suggested that canola attainable yield could be 4 Mg ha-1 with a potential maximum yield of 7 Mg ha-1. However, actual average yields in North America region were ~1.7 Mg ha-1 for the period 2000 to 2014. Available inseason water, water distribution at critical stages, and nutrient supply (soil plus fertilizer) all contribute to a significant portion of canola yield. Other management factors such as seeding rate, rotation, and cultivar selection substantially affect plant performance. Tillage might have an economic and environmental effect, but overall, the outcome of the meta-analysis did not show significant effect on yield. The review suggests that water supply, balanced nutrition, early planting (for both winter and spring types) in shallow depth (10-19 mm), high seeding rate (6 kg ha-1), and diverse rotation (canola every 3 or 4 yr) are among the best management practices to increase yields. Future lines of research should focus on improving planting operations that diminish early-season heterogeneity, finetuning optimal seeding rates based on modern varieties at varying yield environments, and searching for compatible hybrids to replant without heterogeneity at harvest. [ABSTRACT FROM AUTHOR]

Genetic diversity information will be very valuable for future rapeseed (Brassica napus L.) improvement. The genetic diversity and relationships among 92 rapeseed accessions, including 44 from China, 22 from Europe, 16 from the United States, and 10 from Canada, were assessed by 60 random amplified polymorphic DNA (RAPD) and 22 expressed sequence tag (EST)-simple sequence repeat (SSR) primers. In total, 618 RAPD and 117 EST-SSR polymorphic fragments were detected. The average number of polymorphic fragments found by each RAPD primer was 10.3 ranging from 3 to 17 and that detected by each pair of EST-SSR primer was 5.3 ranging from 4 to 7. The unweighted pair-group method with arithmetic mean (UPGMA) cluster analysis revealed that these 92 accessions could be classified into three major clusters. Cluster I consisted of accessions mainly from China, which belong to the semi-winter type. Cluster II contained accessions from Europe and the United States, which belong to the winter type. Cluster III was a semi-winter and spring type mixture group, which contained accessions mainly from China and Canada. The principal component analysis and population structure analysis revealed similar results to the cluster analysis. Analysis of molecular variance result based on four geographic groups indicated that genetic variation was 8.24% among populations of geographic regions and 91.76% within geographic regions. Rapeseed accessions from the United Stated have the greatest genetic distance from accessions of other geographic origins, especially those from China. United States rapeseed could be important germplasm resources for enriching the genetic background of Chinese rapeseed and vice versa. [ABSTRACT FROM AUTHOR]

• Skipping irrigation at the vegetative stage improves water use efficiency in canola. • Soil water extraction depth was similar across irrigation treatments and cultivars. • Canola extracted maximum soil water when stressed during reproductive stage or throughout growing season. The rapid depletion rate of the Ogallala aquifer threatens agriculture sustainability in the U.S. Southern Great Plains (SGP). Adoption of drought tolerant crop with suitable irrigation strategy is critical to improve water use efficiency and sustain crop production in the region. The objective of the study was to assess soil water extraction pattern and water use efficiency of spring canola (Brassica napus L.) under deficit irrigation strategy (DI). Three diverse canola cultivars ('H930', 'H955' and 'L140') were grown under four different irrigation treatments; full-season irrigation (FI), no irrigation at the vegetative stage (VS), no irrigation at the reproductive stage (RS) and dryland (DL). Treatment VS extracted similar amount (20 mm) of total water from planting to harvest as FI in wetter year of 2015. However, VS extracted 10 mm of extra water from soil depth down to 1.6 m until harvest compared to FI in drier year of 2016. As water extraction during reproductive stage in 2016 was almost similar (70 and 67 mm in FI and VS, respectively) in VS and FI, most of the extra water extracted was utilized during vegetative stage when irrigation was skipped in VS. Canola sustained vegetative growth utilizing soil water extraction and efficiently utilized irrigation received during reproductive stage to reduce seasonal evapotranspiration (ET) in VS compared to FI. Treatment RS and DL also reduced seasonal ET, but they reduced average 11 and 13 % oil content compared to FI in 2015 and 2016, respectively. The VS had similar oil content as FI and optimized water use efficiency for biomass (WUE pb), and seed (WUE sy) and oil (WUE oy) yields. Among cultivars, L140 consistently had the greatest WUE pb in both experimental years and 34 and 36 % greater WUE sy and WUE oy in 2016 compared to both H930 and H955, respectively. Adopting spring canola cultivar L140 and skipping irrigation during vegetative stage could maximize water productivity in water deficit conditions of the SGP. [ABSTRACT FROM AUTHOR]

Fourteen accessions (spring and winter types) and four testers (semi-winter type) of rapeseed (Brassica napus L.) were crossed in line × tester mating design to estimate general and specific combining ability for seed yield, yield components, and oil content. The F1 hybrids and their parents were evaluated in four environments in northern China. Highly significant differences were detected among the parents and hybrids for all the traits across environments. Plant height, setting position of first primary branch and length of terminal raceme were controlled by additive genes, whereas primary branches per plant, siliques on terminal raceme, siliques per plant, seeds per silique, seed yield per plant, 1000-seed weight, oil content, and seed yield were controlled by non-additive gene action. The accessions SP-Armada, 9E49, and CZ25 and the tester Zhong9 were good general combiners for seed yield. Among the 56 F1 hybrids, four hybrids: Zhong9 × CZ25, GZ1R × 9E38, Zhong7 × 9E38, and Zhong7 × CZ49 showed higher yield than the control and were the outstanding combinations for seed yield. These hybrids were recommended to be included in future breeding programs for development of new high yielding varieties with more desirable traits. Both winter and spring germplasm have potential in Chinese semi-winter rapeseed breeding program, for seed oil content improvement, more attention may be paid to spring germplasm. [ABSTRACT FROM AUTHOR]