http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/159 2025-10-30T07:28:45Z http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/1013 Title: Allelopathic effect of common weeds on germination and seedling growth of rice in wetland paddy fields of Mizoram, India Authors: Lalruatsanga, H Abstract: Weed invasion of crops contested for environmental resources alongside releasing a certain chemical into the soil and thereby lowering yield potential. The possible allelopathic influence of aqueous extract from leaves and shoots of Alternanthera philoxeroides (Mart.) Griseb., Ludwigia octovalvis (Jacq.) P.H. Raven and Persicaria hydropiper (L.) Delarbe on germination and seedling growth of rice (Oryza sativa L.) was investigated in this study. To prepare the extract, powdered air-dried leaves and shoots of certain weeds were soaked in distilled water (1:10) for 24 h at room temperature, and a different dilution was made from the stock. Aqueous extracts from various plant parts were found to suppress seed germination and the development of rice seedlings. As the extract concentration increases, the intensity of inhibition on germination, shoot length, root length and dry matter reduction increases. The average percent inhibition (API) of leaf extract treatments, namely 8% and 10% A. philoxeroides, 8% and 10% L. octovalvis, and 10% P. hydropiper, was found to be greater than 45%. Shoot extracts containing 2% A. philoxeroides, 2% and 4% L. octovalvis, and 2% P. hydropiper have less than 15% average percent inhibition. According to the findings, different weeds contain allelochemicals of variable types and quantities, and different portions of the same weed have distinct effects on germination and rice seedling development 2022-07-12T00:00:00Z http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/933 Title: Biosynthesis of Silver Nanoparticles Using Selaginella bryopteris Plant Extracts and Studies of Their Antimicrobial and Photocatalytic Activities Authors: Hnamte, Remruattluanga Abstract: The present study focuses on the green synthesis of silver nanoparticles (AgNPs) using aqueous extract of S. bryopteris which is a lithophyte with remarkable resurrection capabilities. These biosynthesized NPs were characterized with the help of UV-vis spectrophotometer, X-ray diffraction (XRD), FT-IR and Transmission electron microscopy (TEM). Formation of AgNPs was confirmed by UV-Visible spectrophotometer analysis which showed surface plasmon resonance (SPR) at around 420 nm. The TEM images showed the nanoparticles to be polydispersed, nearly spherical in shape and have sizes in range 4–30 nm. The synthesized AgNPs possessed high antibacterial activity as well as photocatalytic dye degradation properties under solar light irradiation in the absence of chemical reducing reagents. Stability of bio-reduced silver nanoparticles was analyzed using UV-vis absorption spectra, and their antimicrobial activity was screened against various gram-positive bacteria 2018-03-20T00:00:00Z http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/925 Title: Forest structure and tree diversity along an altitudinal gradient in Sikkim Himalaya Authors: Vanlalhluna, P.C Abstract: The vegetation types of Sikkim Himalayas more particularly Southern Sikkim has not been studied before. This study is the first comprehensive one on the tree species diversity and composition across four forest types (Tropical semi evergreen forest (TSEF), Sub-tropical broad mixed leaved hill forest (STBLHF), Himalayan wet temperate forest (HWTF) and Sub alpine Forest (SAF) in the region. We employed quadrat sampling and all the trees > = 10 cm DBH at 1.37m height were considered for the purpose. A total of 130 tree species belonging to 91 genera and 52 families were recorded in the study sites of which Moraceae and Lauraceae represented the highest number of species (8 each). The tropical semi evergreen forest (TSEF) harboured 61 species, followed by sub-tropical broad mixed leaved hill forest (STBLHF) (59), Himalayan wet temperate forest (HWTF) (43) and sub-alpine forest (SAF) (25). The Shannon-Weiner diversity index (H’) in TSEF, STBLHF, HWTF and SAF was 3.31, 2.92, 2.82, and 2.34 respectively. The H’ showed a linear relation with elevation (R2 = 0.9265, p < 0.05) and the Margalef’s species richness (S) indicated a significant quadratic relation (R2 = 0.9996, p < 0.05) with elevation. A hump-shaped pattern was observed for tree species richness while the DBH size class showed a reverse J shaped pattern. It concluded that tree species diversity in South Sikkim Himalayas is primarily influenced by elevation, showing a linear decline in H′ and a hump-shaped pattern for species richness, peaking at mid-elevations. The reverse J-shaped DBH distribution indicates active regeneration, further supporting the observed diversity pattern. 2024-12-22T00:00:00Z http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/586 Title: Management effect on crop yield in a Gmelina arborea based agroforestry system in humid tropic of northeast India Authors: Vanlalhluna, P.C 2008-06-01T00:00:00Z