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DocumentOther documentHigh-frequency regeneration of plants in vitro from seedling-derived apical bud explants in Tilia mandshurica
XV World Forestry Congress, 2-6 May 2022
2022Also available in:
No results found.Tilia species have taken hold as a crop of interest for both the honey and timber industries, underscoring a need for the development of efficient methods for large-scale propagation. In Tilia species such as T. mandshurica, propagation through seeds is difficult because of a low germination rate (approximately 10-16%) and an extremely hard seed coating that can delay germination for up to two years. Further, cutting propagation is not efficient due to the resulting poor development of root systems. To overcome these difficulties, in vitro culture techniques for plant regeneration have become attractive methods for the propagation of plants. Generally, plant regeneration systems based on apical and axillary bud culture are the most effective method of in vitro propagation
This work was to develop an efficient method for shoot induction and plant regeneration of seedling-derived apical bud explant in Tilia mandshurica. The highest rate (82.2%) of shoot induction was obtained when apical bud explants from juvenile seedlings (5 months old) were cultured on MS medium containing 1.0 mg/L BAP. However, apical bud explants obtained from mature trees (12 years old) did not produce any shoots, even with BAP supplementation. Among the three cytokinins tested for shoot multiplication (BAP, zeatin, and kinetin), BAP was the most effective; the highest number of shoots per explant (2.1) was observed on MS medium supplemented with 1.0 mg/L BAP. For rooting of in vitro-elongated shoots, the highest rooting rate (100%) was observed in half-strength MS medium supplemented with 0.5-1.0 mg/L IBA or 3.0 mg/L NAA. In the acclimatization process, plantlets that were rooted on the IBA (0.5 mg/L)-supplemented medium had the highest survival rate (100%) or root length (18.5 cm). This work showed that a low concentration (0.5 mg/L) of IBA is appropriate for rooting. Keywords: Biodiversity conservation ID: 3622528 -
DocumentOther documentAerenchyma formation in roots and entry point of oxygen in stems of Syzygium kunstleri grown in hypoxic conditions
XV World Forestry Congress, 2-6 May 2022
2022Also available in:
No results found.Aerenchyma serves as a low-resistance O2 transport pathway which makes the plant to survive in flooding conditions. When Syzygium kunstleri, tropical swamp woody plant species, is exposed to hypoxic conditions, primary and secondary aerenchyma(PA, SA) develop in stems and roots. The aim of this study is to investigate the development of PA and SA in the adventitious root, and investigate the entry point of O2 in stem of S. kunstleri sapling grown in hypoxic condition. We prepared cross sections of 0.5cm intervals from adventitious root(>10cm) developed in 0.1% agar medium to observe the longitudinal distribution of PA and SA under light and fluorescence microscopes. The entry point of O2 was investigated by measuring the change of oxygen partial pressure(pO2) by Clark-type O2 microelectrode at the adventitious root while changing the position of stem exposed to N2 or air. N2 or air was injected through a 3cm tube which covered the stem.
Schizogenous aerenchyma(SCHA) was observed in the root tip, lysigenous aerenchyma(LYSIA) was observed in the upper position of the root, and LYSIA and SA were simultaneously observed in the root base. SA was formed inside the LYSIA, and cortex collapse was observed near the root base. O2 concentrations were controlled by N2 or air injections at the position of stem at 0-3 and 3-6cm above water level. N2 injections at the position of stem at 0-3cm above water level resulted in declines of pO2 in the roots from about 14-15 to 3-4kPa. The change in pO2 in the root was affected by removal of SA in stem under water. Air injection at the position of stem 0-3cm above water level after removal of SA in stem didn't make the recovery of the pO2 in the root from 2-4kPa. The light conditions did not affect the changes of pO2 in the root. SCHA, LYSIA and SA developed in order of age of tissue within each adventitious root. The SA in the stem of S. kunstleri positioned near water surface, was investigated as the entry point for atmospheric O2. Keywords: Sustainable forest management ID: 3623148 -
DocumentOther documentMid-term demographic dynamics in stem exclusion stage of beech forest in Ulleungdo Island, South Korea
XV World Forestry Congress, 2-6 May 2022
2022Also available in:
No results found.Long-term observation on forest development processes after various disturbances provides the baseline information such as management options including restoration. We examined changes in forest structure and function and patterns of demographic rates (2009-2019) in young beech forest in Ulleungdo Island, South Korea. Change in mean stem density revealed bell-shaped form and growth rate in mean above ground biomass decreased. By predominant stem density and biomass, beech population exhibited strong influence for whole community patterns. Size distributions of tree community revealed influences from maturity and restrained recruitment of trees. Demographic rates showed interesting patterns because recruitment (from 1.3 in to almost 0) and mortality rates (from 0 to 1.8) have abrupt turnover in 2015. Disturbance events from soil deposition originated by heavy rains after 2017 increased stochastic events of tree death (from 0 to 15%). Our results suggest that in stem exclusion stage there were dramatic turnover between stem recruitment and mortality. In addition, disturbance events have influenced to demographic rates by increasing stochastic tree motality. Keywords: Biodiversity conservation ID: 3622286
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Book (series)YearbookWorld Food and Agriculture – Statistical Yearbook 2024 2024
Also available in:
No results found.The Statistical Yearbook 2024 offers a synthesis of the major factors at play in the global food and agricultural landscape. Statistics are presented in four thematic chapters, covering the economic importance of agricultural activities, inputs, outputs and factors of production, their implications for food security and nutrition and their impacts on the environment. The Yearbook is meant to constitute a primary tool for policymakers, researchers and analysts, as well as the general public interested in the past, present and future path of food and agriculture. -
Book (series)FlagshipThe State of Food and Agriculture 2019
Moving forward on food loss and waste reduction
2019The need to reduce food loss and waste is firmly embedded in the 2030 Agenda for Sustainable Development. Food loss and waste reduction is considered important for improving food security and nutrition, promoting environmental sustainability and lowering production costs. However, efforts to reduce food loss and waste will only be effective if informed by a solid understanding of the problem. This report provides new estimates of the percentage of the world’s food lost from production up to the retail level. The report also finds a vast diversity in existing estimates of losses, even for the same commodities and for the same stages in the supply chain. Clearly identifying and understanding critical loss points in specific supply chains – where considerable potential exists for reducing food losses – is crucial to deciding on appropriate measures. The report provides some guiding principles for interventions based on the objectives being pursued through food loss and waste reductions, be they in improved economic efficiency, food security and nutrition, or environmental sustainability. -
Book (series)Technical studyThe impact of climate variability and extremes on agriculture and food security - An analysis of the evidence and case studies
Background paper for The State of Food Security and Nutrition in the World 2018
2020Also available in:
No results found.Global climate studies show that not only temperatures are increasing and precipitation levels are becoming more varied, all projections indicate these trends will continue. It is therefore imperative that we understand changes in climate over agricultural areas and their impacts on agriculture production and food security. This study presents new analysis on the impact of changing climate on agriculture and food security, by examining the evidence on recent climate variability and extremes over agricultural areas and the impact of these on agriculture and food security. It shows that more countries are exposed to increasing climate variability and extremes and the frequency (the number of years exposed in a five-year period) and intensity (the number of types of climate extremes in a five-year period) of exposure over agricultural areas have increased. The findings of this study are compelling and bring urgency to the fact that climate variability and extremes are proliferating and intensifying and are contributing to a rise in global hunger. The world’s 2.5 billion small-scale farmers, herders, fishers, and forest-dependent people, who derive their food and income from renewable natural resources, are most at risk and affected. Actions to strengthen the resilience of livelihoods and food systems to climate variability and extremes urgently need to be scaled up and accelerated.