The waxy covering on plant leaves, young stems, and fruit is called the cuticle. It is composed of cutin, a wax-like material produced by the plant that is chemically a hydroxy fatty acid.
Remember that the top of the leaf has the protective coating of the cuticle and then a layer of cells known as the upper epidermis. On the bottom of the leaf is another protective layer of cells. Because it is at the bottom of the leaf, this layer is known as the lower epidermis. It is generally waxy to protect the leaf and prevent water loss. When you touch a leaf, you may feel this waxy coating, and on some plants, such as holly, you may actually be able to see the waxy coat shine a bit. Below the cuticle is the M. leprae is an aerobic bacillus (rod-shaped) surrounded by the characteristic waxy coating unique to mycobacteria. In size and shape, it closely resembles Mycobacterium tuberculosis. Due to its thick waxy coating, M. leprae stains with a carbol fuchsin rather, than with the traditional Gram stain. The culture takes several weeks to mature. Optical microscopy shows M. leprae in clumps, rounded masses, or in groups of bacilli side by side, and ranging from 1–8 μm in length and 0.2–0.5 μm in diameter. Plants without a cuticle live underwater. The purpose of the cuticle is to prevent the leaves of a plant from losing moisture to the atmosphere. Pine needles have a thick waxy … coating that prevents moisture loss during the winter, when the air is dry. Cacti have modified leaves that are mostly cuticle, because the use their stems for photosynthesis. This answer refers to the Botanical reference of Cuticle; refer to the related question What is a cuticle for the Anatomical definition. Plant cuticles are a protective waxy covering produced only by the epidermal cells of leaves, young shoots and all other aerial plant organs without periderm. A cuticle /ˈkjuːtɪkəl/ , or cuticula, is a term used for any of a variety of tough but flexible, non-mineral outer coverings of an organism, or parts of an organism, that provide protection. Various types of cuticle are non-homologous, differing in their origin, structure, function, and chemical composition.  The microorganism responsible for this disease, Mycobacterium leprae, is a gram-positive, rod-shaped bacteria with a thick waxy coating. Due to this coating, it cannot be stained with the regular gram method and instead is stained with carbolfuschin. It also has a long incubation period, meaning that it may be a long time before symptoms appear, as long as twenty years in some cases. Answer by Bruce Pedersen. Confidence votes 27.8K. Plants such as Hoyas are described as having waxy leaves because they have a waxy feel. The waxiness is in actual fact an extra thick cuticle layer on the leaf, designed to protect the leaf from dehydration. See related link for picture.  This outermost layer is called the cuticle. It is generally waxy to protect the leaf and prevent water loss. When you touch a leaf, you may feel this waxy coating, and on some plants, such as holly, you may actually be able to see the waxy coat shine a bit. Below the cuticle is the epidermis. On the top of the leaf, this is known as the upper epidermis
http://study.com/academy/lesson/structure-of-leaves-the-epidermis-palisade-and-spongy-layers.html https://en.wikipedia.org/wiki/Mycobacterium_leprae http://www.answers.com/Q/What_is_a_plant_cuticle https://en.wikipedia.org/wiki/Cuticle http://web.mst.edu/~microbio/BIO221_2010/M_leprae.html http://www.answers.com/Q/What_does_waxy_leaves_mean http://study.com/academy/lesson/structure-of-leaves-the-epidermis-palisade-and-spongy-layers.html
what is thick waxy coating means in microbiology