Podostemaceae a family of aquatic flowering plant restricted to river rapids and waterfalls are widely reported to be the high incidence of endemism and in need for conservation. The present study analyses endemism and conservation status of the Podostemaceae in northeastern floristic region Thailand using past and current taxonomic records personal field collections geographic ranges IUCN assessment and a combination of river number in which a species occurs. The plants grown in one river and two rivers are considered as narrow endemic species. Among the six genera and 22 species recognized two genera are endemic eighteen species are endemic to Thailand eleven species of the 18 are narrowly distributed and confined in northeastern floristic region and the other 4 species are not endemic. Considering the conservation status two species are classified as Critically Endangered distributed in a single river ten species as Vulnerable distributed in 1-2 rivers six species as Near Threatened two species as Least Concern and two species as Data Deficient. Loei province is the most species-rich area in Thailand with 12 species five of them are restricted in Loei.

Recent explorations of Podostemaceae have discovered 2 new species to science (Dalzellia TWA-216 และ Hydrobryum TWA-198) from Phitsanulok Province and 3 more genera and six more species from previously known (2 genera and 4 species). Totally five genera and 10 species occur in Phitsanulok and Phetchabun provinces. Based on morphological and molecular evidence the taxa are classified into subfamily Tristichoideae including 2 genera and 3 species (Dalzellia 2 spp. and Terniopsis 1 sp.) and subfamily Podostemoideae consisting 3 genera and 7 species (Hanseniella 1 sp. Hydrobryum 5 spp. and Thawatchaia 1 sp.). The species found in both provinces are Hy. phetchabunense and Hy. tardhuangense while D. kailarsenii is found only in Phetchabun. The plants discovered only in Phitsanulok include Dalzellia TWA-216 Hydrobryum TWA-198 Han. heterophylla Hy. bifoliatum Hy. kaengsophense Th. trilobata and T. minor. Among the species found Hy. tardhuangense and Th. trilobata are also distributed to the Lao PDR and the rests are endemic to Thailand.

The purpose of this study was the design and development of a Computer Assisted Instruction program for a Principles of Biology course on the topic of cell division. The sample group was 175 students taken from the food and nutrition major studying for a bachelor’s degree in the second term of the first academic year (2011) from the Faculty of Technology and Nutrition Rajamangala University of Technology Phra Nakorn. Statistical analysis of the mean and standard deviation were preformed of the test’s satisfaction toward the Multimedia Computer Program along with T-test analysis of the test data to determine learning achievement before and after use of the Computer Assisted Instruction. The results found that learning achievement scores for the Multimedia Computer Program after Computer Assisted Instruction were significantly higher than before at the 0.05 level. The test’s satisfaction toward learning via the Multimedia Computer Program was also high.

In order to elucidate the floral ontogeny of certain Thai species of the subfamily Podostemoideae the flowering shoots of Hanseniella heterophy/la Hydrobryum loeicum and Hy. tardhuangense were observed using scanning electron microscope. In all species studied. the flowering shoots protrude from the cavities where the tufted leaves arise on the crustose root. Mostly the two outer bracts are leaf-like interpreting that the flowering shoots are converted from the vegetative shoots. In Hanseniel/a bracts in the early developmental stage are similar shapes but different sizes arranging in 4 rows. In the mid-stage the ventral bracts differentiate into normally 2 lobes occasionally 3 lobes whereas the dorsal bracts develop into long deltoid shape. In Hydrobryum the arrangement of bracts is distichous. The spathellas in all species initiate from tissue surrounding the floral meristem. Prior to the fusion of ventral and dorsal apical margins the spathella apices become a triangle space in Hanseniella narrow long space in Hy. loeicum and two-lipped in Hy. tardhuangense; and the floral organs are initiated inside the spathella. The two tepal primordia the primary androecial primordium and the gynoecial primordium are initiated simultaneously. The two stamen primordia are differentiated from the primary androcial primordium when the gynoecium changes into a cylindrical shape and two carpel primordia are initiated. These dramatic ontogenetic changes and heterochronic shifts in the initiation of floral organs are highly specialized and very distinct floral development which have not found in any families of flowering plants.

The species composition of Podostemaceae was studied in Loei northeastern Thailand from November 2009 to July 2010 by extensive surveying in the rapids and waterfalls inside and outside of national parks wildlife sanctuaries and protected areas. The samples collected are classified into 2 subfamilies which are Tristichoideae and Podostemoideae. The former contains 2 genera and 3 species Dalzellia kailarsenii Terniopsis sp. 1 Terniopsis sp. 2. The latter has 4 genera and 9 species Hanseniella heterophylla Hydrobryum japonicum Hydrobryum loeicum Hydrobryum tardhuangense Hydrobryum vientianense Hydrobryum sp. 1 Hydrobryum sp. 2 Polypleurum sessile Thawatchaia trilobata. The highest number of species occurs in Hydrobryum with 6 species following by Terniopsis with 2 species. The other four genera have one species each. Based on morphological and molecular analyses revealed that 2 species of the genus Hydrobryum are new and 2 taxa of Terniopsis are also new species. Polypleurum sessile and Thawatchaia trilobata are new recorded in Loei province. The result from this study indicates that the genus richness is relatively high in Loei province which encompasses 60% of the total number of genera (10) in Thailand. The plants in vegetative phase are completely submersed in swiftly running water during a warm wet season (May-October). The plants flower and set fruits and seeds when exposing to air during water level drop in a cool dry season (November- February).