Plant leaf parameters such as stomatal index, stomata type, microscopic features, and powder microscopy are important taxonomic used to properly identify species differentiate one from another these is a vital keys in the pharmacognostic study of medicinal plants because play role distinguishing crude drugs even when they fragmented or powdered. Also, extractive retention factor, ash value, phy...

MicroRNAs and trans-acting siRNAs (ta-siRNAs) have important regulatory roles in development. Unlike other developmentally important regulatory molecules, small RNAs are not known to act as mobile signals during development. Here, we show that low-abundant, conserved ta-siRNAs, termed tasiR-ARFs, move intercellularly from their defined source of biogenesis on the upper (adaxial) side of leaves ...

Elaphoglossum luridum (Fée) Christ. (Dryopteridaceae) is an epiphytic fern of the Atlantic Forest (Brazil). Anatomical and physiological studies were conducted to understand how this plant responds to water stress. The E. luridum frond is coriaceus and succulent, presenting trichomes, relatively thick cuticle, and sinuous cell walls in both abaxial and adaxial epidermis. Three treatments were a...

Cis-acting regulatory elements of the wheat acetyl-CoA carboxylase (ACC) gene family were identified by comparing the promoter activity of 5' end gene fragments fused to a reporter gene in two transient expression systems: wheat protoplasts and epidermal cells of mature embryos. Expression of the plastid and the cytosolic ACC genes is each driven by two nested promoters responsible for the synt...

To clarify the mechanisms of methane transport from the rhizosphere into the atmosphere through rice plants (Oryza sativa L.), the methane emission rate was measured from a shoot whose roots had been kept in a culture solution with a high methane concentration or exposed to methane gas in the gas phase by using a cylindrical chamber. No clear correlation was observed between change in the trans...

Hu and Schmidhalter (2008) conducted a study with wheat seedlings growing in saline and non-stressed (control) conditions with the aim of identifying and quantifying the cellular basis for the reduction in leaf growth. We applaud their goals as salinity is an important issue for plant ecology and food production; however, we have concerns about the methodology used and the subsequent conclusion...

Bustam BM (2010) Systematic studies of Australian stipoid grasses (Austrostipa) based on micro-morphological and molecular characteristics. Biodiversitas 11: 9-14. This research is one of many studies on stipoid grasses organized by the International Stipeae Working Group (ISWG). This research tested the subgeneric classification of Austrostipa proposed by Jacobs and Everett (1996) and tested h...

It was reported in 1930 (2) that exposure to polarized light had been found to induce hydrolysis of starch grains in the mesophyll of living leaves. Similar action on starch grains in vitro has also been observed (1, 3, 6). The present paper gives an account of some experiments on the hydrolyzing influence of polarized light when applied to foliar stomata. In many plant forms the guard cells of...

ABSTRACT Physiological and structural alterations in broad beans (Vicia faba cv. Giza Blanka) in response to 10 M CuSO4, 10 M CdSO4 and a mixture of both solutions were recorded in 15and 25day-old plants. These treatments caused significant reductions in shoot height, leaflet area, fresh and dry weights, stomatal frequency, cell area in abaxial epidermis of leaflets, length and width of stomata...

In plants belonging to the Ranunculaceae the floral nectaries may differ in origin, location in the flower, shape and structure. In many cases they are defined as modified tepals or modified stamens. The nectary organs in this family are frequently termed "honey leaves," and staminodial origin is attributed to them. Gynopleural and receptacular nectaries are rarely found in Ranunculaceae. To da...