Calmodulin, a primary plant calcium receptor, is known to be intimately involved with gravitropic sensing and transduction. Using the calmodulin-binding inhibitors trifluoperazine, W7 and calmidazolium, gravitropic curvature of Arabidopsis thaliana (L.) Heynh, ecotype Landsberg, roots was separable into two phases. Phase I was detected at very low concentrations (0.01 microM) of trifluoperazine and calmidazolium, did not involve growth changes, accounted for about half the total curvature of the root and may represent the specific contribution of the cap to gravity sensing. Phase II commenced around 1.0 microM and involved inhibition of both growth and curvature. The agr-3 mutant exhibited a reduced gravitropic response and was found to lack phase I curvature, suggesting that the mutation alters either use or expression of calmodulin. The sequences of wild-type and agr-3 calmodulin (CaM-1) cDNAs, which are root specific were completely determined and found to be identical. Upon gravitropic stimulation, wild-type Arabidopsis seedlings increased calmodulin mRNA levels by threefold in 0.5 h. On the other hand, gravitropic stimulation of agr-3 decreased calmodulin mRNA accumulation. The possible basis of the two phases of curvature is discussed and it is concluded that agr-3 has a lesion located in a general gravity transmission sequence, present in many root cells, which involves calmodulin mRNA accumulation.

The role of research in business schools is considered to be twofold. It must increase society's understanding of management, and it should have practical value. Currently, much of the research conducted in business schools is considered to be academically rigorous, but at the same time, it is lacking in relevance for practising managers. Reasons for this, and some of the implications for business schools are discussed. Some of the ways for encouraging more research with direct applicability to the business community are put forward. Résumé Le rôle de la recherche dans les écoles de gestion est double: permettre à la société de d'augmenter son intelligence du concept de gestion et résoudre des problèmes concrets. Présentement la recherche que l'on réalise dans les écoles de gestion est généralement considérée comme étant scientifiquement rigoureuse; malheureusement, elle n'est pas toujours utile aux cadres en exercice. Cet article énumère les raisons de cette situation et quelques conséquences sur les écoles. On y trouve quelques façons d'encourager la recherche ayant un apport direct au milieu des affaires.

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