Content uploaded by Wonwoo Cho
Author content
All content in this area was uploaded by Wonwoo Cho on Jul 10, 2018
Content may be subject to copyright.
Effects of Rice Hull Cover for Seed Germination, Types of Tray and Soil, Shading Conditions for Seedling Growth of Codonopsis pilosuala
Abstract
This study was conducted to determine the effects of rice hull cover on seed germination and tray types, soil types, shading conditions for seedling growth of Codonopsis pilosuala. We also examined the feasibility of cultivation of small seedlings transplanted in the Gyeonggi-do area for a month. Under control condition, the seed germination was 8% whereas it dramatically increased to 78% under rice hull cover treatment. Under the different conditions (tray types, soil types, and shading conditions), young seedlings showed the best quality without shading in TKS soil of 50 plug cell tray, with the growth characteristics of plant height (11.9 cm), number of leaves (71), leaf width (3.1 cm), leaf length (2.6 cm), and root length (14.3 cm). Seedling quality was the best without any shading in TKS+perlite, with the physiological characteristics of evaporation (3.9 mmol{\cdot}m^{-2}s^{-1}), carbon assimilation (9.1 ?mol{\cdot}m^{-2}s^{-1}), and water use efficiency (2.2 ?mol{\cdot}m^{-2}s^{-1}). Considering the economical, morphological, physiological and survival rate of the seedlings, it was an ideal method for transplanting seedlings in the field after they have been grown for 30-45 days in TKS and TKS+perlite of 200 plug cell tray in 0% or 30% shaded conditions. As the results of 5 months examination on the possibility to cultivate Codonopsis pilosuala in the Gyeonggi-do area, 88% to 96% of survival rate was observed with normal induced flowers. Therefore, cultivation of Codonopsis pilosuala was possible in the Gyeonggi-do area. While there were symptoms of etiolation and wilting under no shading condition, they did not appear in 30% and 70% shading conditions. Therefore, cultivation of Codonopsis pilosuala is considered to be necessary 30% or 70% shading.
... Selective allelopathy [61,62] provides a means for reducing competition for resources [63] on the one hand and permits seed germination of other species for facilitative plant-plant interaction on the other hand [64]. Seed germination of Codonopsis pilosuala was dramatically enhanced under rice hull cover treatment [65] and rice hull was found to induce dark seed germination of Monochoria vaginalis, a noxious weed commonly requiring light for germination [66]. Interestingly, only unsterilized Monochoria seeds were able to germinate in the darkness by rice hull extract, leading to the conclusion that rice hulls might promote microbial growth that acts to weaken the seed coat and consequently facilitates germination [66]. ...
The seed is the fundamental unit of the dispersal of dry, dehiscent fruits, in which the fruit splits open at maturity to allow for seed dispersal. However, dry fruits may be indehiscent and therefore represent the dispersal unit (DU). Cereals possess a one-seeded fruit, whereby the seed coat and the fruit coat are fused together to generate the caryopsis. This caryopsis may be covered by floral bracts to generate two types of DUs, namely florets, whereby the caryopsis is enclosed by the lemma and the palea (e.g., Avenasterilis) or spikelet, whereby the floret(s) is further covered by the glumes (Triticum turgidum var. dicoccoides). Here, we highlight the dead coverings enclosing the caryopsis in cereals, namely the husks as an integral component of the dispersal unit that play multifaceted roles in grain biology. Thus, besides protection and dispersal means, the husks function as a rich maternal supply of proteins and metabolites for enhancing growth and development, combat potential pathogens as well as confer tolerance to abiotic stresses. These attributes might have broad implications for crop performance, plant population dynamics and diversity in ecological systems, and for conservation of genetic resources in seed banks.
High temperature stress is a major limiting factor in the growth and development of tall fescue (Festuca arundinacea) in transitional and warm climatic regions. In this study, we evaluated the photosynthesis, PSII functionality, and antioxidant activity of two tall fescue cultivars, Jaguar 3 brand (heat-tolerant) and TF 66 (heat-sensitive) in response to high temperature stress. High temperature stress caused a net photosynthetic rate reduction in the two plants due to stomatal and non-stomatal limitations, photoinhibition increase, and Rubisco activity reduction. High temperature stress modified PSII functionality in leaves of the two plants, manifested by lower variable chlorophyll fluorescence yield (Fv), maximum photochemical efficiency of photosystem II in dark adapted leaves (Fv/Fm), and efficiency of the open reaction centre in light (ΦPSIIopen) in the two heat shocked cultivars. Heat stress led to reductions in the chlorophyll a+b and chlorophyll/carotenoid ratios and to an increase in the chlorophyll a/b ratio for the two stressed cultivars. Moreover, high temperature stress significantly increased lipid peroxidation, decreased cell membrane thermostability, and changed the activities of ascorbate peroxidase (APX) and superoxide dismutase (SOD) in the leaves of both plants. All the above effects induced by high temperature were more expressed in the TF 66 than in Jaguar 3 brand. Our results contain some insights which may prove useful in the selection and breeding of heat-tolerant tall fescue turfgrass cultivars.
Profi-Catalogue. Floragard Vertriebs GmbH
- Floragard
Growth and nutrient uptake of tomato plug seedlings influenced by elevated blending rate of perlite in coir and peatmoss substrates
- J M Choi
- J W Ahn
- J H Ku