A C° finite element formulation for flexure‐membrane coupling behaviour of an unsymmetrically laminated plate based on a higher‐order displacement model and three‐dimensional state of stress and strain is presented. This theory incorporates the more realistic non‐linear variation of displacements through the plate thickness, thus eliminating the use of a shear correction coefficient. The discrete element chosen is a nine‐noded quadrilateral with 12 degrees of freedom per node. The computer program developed incorporates the realistic prediction of interlaminar stresses from equilibrium equations. The present solution for deflection and stresses is compared with those obtained using three‐dimensional elasticity theory, another higher‐order shear deformation theory and Mindlin theory. In addition, numerical results for unsymmetric sandwich plates are presented for future reference.

Abetraet-New numerical algorithms are proposed for the accurate evaluation of transverse stresses in general composite and sandwich laminates. A set of higher-order theories with Co isoparameteric finite elements and exact three-dimensional equilibrium equations are used. The integration of the equilibrium equations is carried out through exact surface fitting method, direct integration method and forward and central direct finite difference methods. Sixteen-and nine-noded quadrilateral Lagrangian elements with selective numerical integration techniques based on Gauss-Legendre product rules are used in the analysis. Validity of the present numerical techniques and the higher-order theories are demonstrated by comparing the present results with the available elasticity and other closed-form solutions for cross-ply, angle-ply and sandwich laminates. The exact surface fitting method is seen to give accurate estimate of the transverse stresses compared to other methods.

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The distribution of endophytes (fungal and bacterial) is ubiquitous and almost without exception; the endophytes have been reported from all tissues, including leaves, stems, roots, fl owers and fruits. As typical symptomless organisms, in contrast to their pathogenic counterparts, they pose a serious challenge in explaining their continued maintenance in plants. How do plants tolerate them? And how do the endophytes contain the plant defences? But a more intriguing and enigmatic issue with many endophytes is the fact that they mimic the production of specifi c plantassociated secondary metabolites (e.g. taxol, camptothecin and rohitukine) in culture, independent of the host tissue. Several theories including the possibility of horizontal gene transfer from the respective hosts have

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