Effect of aluminum oxide nanoparticle on sporogenesis and gametophyte development in bean (Phaseolus vulgaris L.)

The purpose of the study was to determine the exact developmental stages of reproductive organs and to compare the effects of aluminum oxide nanoparticles on different ovule development and pollen grains in bean plant as one of the main sources of food in the world. Bean plants were cultured in greenhouse conditions and treated with aluminum oxide nanoparticles in different concentrations (0.1, 0.01, 0.001 g/l). Flowers and buds were collected, in different sizes, and fixed in a FAA, dehydrated, embedded in paraffin and sliced with a rotary microtome. The staining was carried out using Hematoxylin-Eosin. Developmental stages of ovule and pollen grains were studied and compared in control plants and experimental plants. The results showed that in control plants, different developmental stages of ovule and pollen grains were followed as the prior reports. Ovule was anatropous, embryo sac is of polygonum type, tetrad arrangement is often linear and T-shaped some times. Anther was tetrasporangiate, tetrad arrangement was tetrahedral, tapetum was of secretory type at beginning, and plasmodial at the late developmental stages. Pollen grains were spherical to ovular shaped. Results showed that the treatments were not effective in the development of ovule, but cause to decrease bioavailability and increased thickness of the intine layer in pollen grains. Irregularities in tetrad microspores and structure of pollen grains are some effects of treatment by aluminum oxide nanoparticles.