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Introduction: Stress-induced volatile organic compounds (VOCs) that induce plant immunity bear potential for biocontrol. Here, we explore the potential of nonanal to enhance the seed yield of common bean (Phaseolus vulgaris) under open field conditions that are realistic for smallholder farmers. Methods and results: Using plastic cups with a nonanal-containing lanolin paste as low-cost dispensers, we observed that exposure of Flor de Junio Marcela (FJM) plants over 48h to airborne nonanal was followed by a 3-fold higher expression of pathogenesis-related (PR) genes PR1 and PR4. Both genes further increased their expression in response to subsequent challenge with the fungal pathogen Colletotrichum lindemuthianum. Therefore, we conclude that nonanal causes resistance gene priming. This effect was associated with ca. 2.5-fold lower infection rates and a 2-fold higher seed yield. Offspring of nonanal-exposed FJM plants exhibited a 10% higher emergence rate and a priming of PR1- and PR4-expression, which was associated with decreased infection by C. lindemuthianum and, ultimately, a ca. 3-fold increase in seed yield by anthracnose-infected offspring of nonanal-exposed plants. Seeds of nonanal-exposed and of challenged plants contained significantly more phenolic compounds (increase by ca 40%) and increased antioxidant and radical scavenging activity. Comparative studies including five widely used bean cultivars revealed 2-fold to 3-fold higher seed yield for nonanal-exposed plants. Finally, a cost-benefit analysis indicated a potential economic net profit of nonanal exposure for some, but not all cultivars. Outlook: We consider nonanal as a promising candidate for an affordable tool that allows low-income smallholder farmers to increase the yield of an important staple-crop without using pesticides [ABSTRACT FROM AUTHOR]

Study aim: To assess the influence of juggling training on mental rotation performance in children. Material and methods: Two groups of girls aged 6-14 years were studied: experimental (EG; n = 26) and control (CG; n = 24). All girls solved a mental rotation task with 3-D block figures on computer screen (pre-test). After the initial test, EG girls participated in juggling training for 3 months; the CG girls participated in light strength training with theraband stretch bands. After 3 months, all girls solved the mental rotation task again (post-test). The post-pre differences in the mental rotation performance were recorded. Results: Children who learned juggling performed the mental rotation task significantly (p less than 0.05-0.01) faster, in terms of reaction time, at non-zero angular disparity than their mates who were strength-trained. Conclusions: Since mental rotation skills enhance spatial imagination, problem solving and mathematical skills, it may be assumed that juggling training enhances also other cognitive domains and is worth implementing in the education process. (Contains 2 figures and 2 tables.)

This article presents a reanalysis of the data of 862 second and fourth graders collected in two previous studies, focusing on the influence of method (psychometric vs. chronometric) and stimulus type on the gender difference in mental-rotation accuracy. The children had to solve mental-rotation tasks with animal pictures, letters, or cube figures, either in a chronometric condition (computerized) or in a psychometric condition (paper-and-pencil). Results show a slight male advantage in mental-rotation accuracy, which is neither influenced by method nor by stimulus type. However, mental-rotation accuracy differed between the stimulus types, with the highest accuracy in animal pictures and the lowest accuracy in cube figures, and between age groups, with better performance in fourth graders than in second graders in both conditions. Results show that psychometric and chronometric mental-rotation tests with all the stimulus types are more or less similarly usable with children of that age.