Unscrambling confounded effects of sowing date trials to screen for crop adaptation to high temperature

Against the backdrop of climate change, genotypes with improved adaptation to elevated temperature are required; reliable screening methods are therefore important. Sowing date experiments are a practical and in expensive approach for comparison of large collections of lines. Late-sown crops usually experience hotter conditions and phenotypes thus partially capture this environmental influence. Two sets of confounded factors, however, limit the value of sowing date trials. First, daily mean temperature correlates with both minimum and maximum temperature, photoperiod, radiation and vapour pressure deficit, and it may also correlate with rainfall. Second, temperature alters the genotype-dependent phen-ology of crops, effectively shifting the timing and duration of critical periods against the background of temperature and other environmental variables.Here we advance a crop-level framework to unscramble the confounded effects of sowing date experiments; it is based on four physiological concepts: (1) annual crops accommodate environmen-tal variation through seed number rather than seed size; (2) seed number is most responsive to the environment in species-specific critical windows; (3) non-stressful thermal effects affecting seed set through development and canopy size can be integrated in a photothermal quotient relating intercepted photosynthetically active radiation (PAR) and mean temperature during the critical window; (4) stressful temperature reduces yield by disrupting reproduction.The framework was tested in a factorial experiment combining four chickpea varieties with puta-tively contrasting adaptation to thermal stress and five environments resulting from the combination of seasons and sowing dates. Yield ranged from 13 to 577 g m−2. Shifts in phenology led to contrasting photothermal conditions in the critical window between flowering and 400◦C d after flowering that were specific for each variety–environment combination. The photothermal quotient ranged from 2.72to 6.85 MJ m−2 ◦C−1; it explained 50% of the variation in yield and maximum temperature explained 32% of the remaining variation. Thus, half of the variation in yield was associated with developmental,non-stressful thermal effect and (at most) 16% of the variation was attributable to thermal stress. Thephotothermal quotient corrected by vapour pressure deficit accounted for by 75% of the variation in yieldand provided further insight on photosynthesis-mediated responses to temperature.Crop adaptation to non-stressful, developmental thermal effects and stressful temperatures disrupting reproduction involve different physiological processes and requires partially different agronomic and breeding solutions. Our analytical approach partially separates these effects, adds value to sowing datetrials, and is likely to return more robust rankings of varietie

Soybean production potential in Africa

Soybean (Glycine max [L.] Merr.) could possibly become a major crop in Africa due to its many uses as a food, feed, and in industry. Also, its ability to undertake symbiotic nitrogen fixation is a great advantage over cereal crops. This study simulated yield potential across west and east Africa. A number of areas were excluded from soybean production because of inadequate early season rains to allow timely sowing of the crop. Among the remaining areas, average yields greater than 200 g m−2 were commonly simulated. Two drought traits were examined as plant modifications to increase yields. These results identified those areas and plant traits in Africa where soybean has the potential to be an important, viable crop

Is nitrogen accumulation in grain legumes responsive to growth or ontogeny?

Peer Revie

Education, digitization and literacy training. A historical and cross-cultural perspective.

In this article, I deal with the transition from traditional ‘school’ forms of instruction to educational processes that are fully mediated by digital technologies. Against the background of the idea the very institution ‘school’ is closely linked to the invention of the alphabetic writing system and to the need of initiating new generations into a literate culture, I focus on the issue of literacy training. I argue that with the digitization of education, a fundamental transition takes place regarding what it means to be literate, but also what it means to educate and to be educated. I do so by developing a ‘techno-somatic’ approach, which means that I look at the use of concrete instructional technologies, and the bodily disciplines that are involved. I set out a double comparison in which I contrast existing, ‘traditional’ ways of learning how to read/write with the way in which literacy training looked like before the nineteenth century, on the one hand, and with the initiation into literacy in the Chinese/Japanese language, on the other hand. I argue that these comparisons shed light on the differences between traditional and digital literacy. More precisely, I show that in each case, a different relation toward what it means to produce script is involved. As such, both forms of literacy go together with different spaces of experience and senses of being-able, and therefore with altogether different ideas of what education is all about

Sport, War and Democracy in Classical Athens

This article concerns the paradox of athletics in classical Athens. Democracy may have opened up politics to every class of Athenian but it had little impact on sporting participation. The city’s athletes continued to drawn predominantly from the upper class. It comes as a surprise then that lower-class Athenians actually esteemed athletes above every other group in the public eye, honoured them very generously when they won, and directed a great deal of public and private money to sporting competitions and facilities. In addition athletics escaped the otherwise persistent criticism of upper-class activities in the popular culture of the democracy. The research of social scientists on sport and aggression suggests this paradox may have been due to the cultural overlap between athletics and war under the Athenian democracy. The article concludes that the practical and ideological democratization of war by classical Athens legitimized and supported upper-class sport

Marketing (as) Rhetoric: paradigms, provocations, and perspectives

In this collection of short, invited essays on the topic of marketing (as) rhetoric we deal with a variety of issues that demonstrate the centrality of rhetoric and rhetorical considerations to the pursuit of marketing scholarship, research and practice. Stephen Brown examines the enduring rhetorical power of the 4Ps; Chris Hackley argues for the critical power of rhetorical orientations in marketing scholarship but cautions us on the need to work harder in conceptually connecting rhetorical theory and modern marketing frameworks; Shelby Hunt explains how rhetorical processes are incorporated in his inductive realist model of theory generation, using one of his most successful publications as an illustration; Charles Marsh demonstrates what Isocrates’ broad rhetorical project has to teach us about the importance of reputation cultivation in modern marketing; Nicholas O’Shaughnessy uses an analysis of Trump’s discourse to argue that political marketing as it is currently conceived is ill-equipped to engage effectively with the rhetorical force of Trump’s ‘unmarketing’; Barbara Phillips uses Vygotsky’s work on imagination to investigate the important of pleasure and play in advertising rhetoric; and finally, David Tonks, who in many ways started it all, reiterates the need for marketers to recognise the strength of the relationship between marketing and persuasion

Play at work, learning and innovation

Suggesting a virtuous triangle constituting public service innovation of new governances, innovation and learning, the paper examines how and why a particular mode of learning occurs: that of play. Having identified an absence of research literature on play as a catalyst for new ideas in public services, the paper argues that the diversified nature of public services and disciplinary intermixing offers fertile ground for playing with new service ideas. Our conception of play avoids functional interpretations, such as Amabile or individualizing the results of play and instead draws upon Vygotsky’s social learning theory to conceptualize play as a group activity from which new ideas emerge and suggest a new framework for understanding purposive play at work and the contribution it can make to public service innovation