Influence of Amanita muscaria (class Agaricomycetes, fam. Amanitaceae) and Flammulina velutipes (class Agaricomycetes, fam. Physalacriaceae) on the growth and development of seedlings of Picea abies (class Pinophyta, fam. Pinaceae) and Abies sibirica (class Pinophyta, fam. Pinaceae)

The article presents studies of the influence of Amanita muscaria and Flammulina velutipes on the growth and development of seedlings of species of the Pinaceae family. The positive effect of mycorrhization by these fungi species on the growth and development of Picea abies and Abies sibirica was established. Thus, the presence of Flammulina velutipes and Amanita muscaria in the substrate accelerated the appearance of the first shoots by 4–8 days. Mycorrhization of Amanita muscaria influenced the morphometry of the seedlings of Picea abies and Abies sibirica. The main root length changed: in Picea abies it increased by 17.2%, in Abies sibirica it decreased by 12.9%, compared with the control group. In the presence of Amanita muscaria, the length of lateral roots increased by 51.0% in Picea abies seedlings, and by 32.4% in Abies sibirica seedlings, compared with the control group. The height of the aerial part in the presence of Flammulina velutipes increased in comparison with the control group in Picea abies seedlings by 52.2% and in Abies sibirica seedlings by 18.3%. Mycorrhization of Amanita muscaria seedlings caused an increase in the stem diameter at the root collar of Picea abies seedlings by 13.6%, and Abies sibirica seedlings by 12.1%.

Growth and Nitrogen Retranslocation of Nutrient-Loaded Clonal Betula alnoides Transplanted with or without Fertilization

Nutrient loading can improve the growth and nutrient content of nursery-grown Betula alnoides Buch.-Ham. ex D. Don, but it is unknown whether nutrient loading enhances growth and nutrient uptake after transplanting. Plants were grown with three nutrient loading treatments (N100, N200, and N400; 100, 200, and 400 mg N per plant as 15N-urea) in nursery containers and then transplanted into plastic pots, with or without controlled-release fertilizer (F0 and F10, 0 and 10 g per plant). The N400 plants had a smaller size but higher nitrogen concentration relative to the N100 and N200 plants before transplanting. However, 180 days after transplanting, the N200 and N400 plants had superior root collar diameter, root length, and root area compared to the N100 plants, due to an increase in 15N retranslocation to new stems and new leaves. Moreover, transplant fertilization (F10) enhanced the height, root collar diameter, root length, and plant dry mass, but not nitrogen concentration or retranslocation, relative to F0. We recommend that medium- and high-dose nutrient loading is implemented in B. alnoides nurseries to optimize growth after transplanting. Additional fertilizer at transplanting may be advantageous in supporting growth, owing to the rapid depletion of nutrient reserves after planting out in the field.

Growth Dynamics and Tree Shape of Common Beech ( Fagus sylvatica L.) in the International Provenance Test

Provenance tests of forest tree species are important experiments in silviculture and tree breeding. Their results provide information about provenances' growth, adaptability, and other features. The research aimed to determine the dynamics of growth and tree shape of common beech plants per provenances in the international provenance test in Bosnia and Herzegovina to choose the best provenances considering wood production and quality. Research was conducted in the provenance test containing eight provenances from Bosnia and Herzegovina, four from Germany, three from Serbia, two each from Croatia, Romania, and Switzerland, and one from Hungary. Provenance test was established in 2007 by planting 2-year-old and 3-year old seedlings. Height and root collar diameter were measured, and tree shape was assessed in 2019. Data were processed in SPSS 26.0. Descriptive statistics, variance analysis, multiple Duncan's test for all traits, and Pearson's coefficient of corelation among morphological traits and tree shape were calculated. Variance for the height and root collar diameter showed statistically significant differences among different ages of plants and among provenances. Provenance from Croatia (Dilj Čaglinski) had the highest, and provenance from Romania (Alba-Iulia) had the lowest average height. The highest average value of root collar diameter had provenance Dilj Čaglinski, and the lowest value had provenance Sihlwald (Switzerland). The highest percentage of category 10 (ideal tree form) had provenance Bad Wildbad (Germany), and categories 1-4 (no silviculture value) had provenance Alba-Iulia (Romania). Pearson's coefficient showed that height, root collar diameter, and tree shape are highly correlated. Considering all the above, when planning forest-breeding works, it is recommended to continue the research and favor provenances with the best growth and tree shape.

Effect of Different Types of Mulching on Soil Properties and Tree Growth of Magnolia champaca Planted at the Montane Rainforest in Cameron Highlands, Pahang, Malaysia

Tropical Montane Cloud Forest (TMCF) is among the most vulnerable habitats to fragmentation, deforestation, and global climate change. A successful restoration program requires a comprehensive understanding of variables influencing seedling efficiency. This study was conducted on Sg. Terla Forest Reserve Cameron Highlands, Pahang, Malaysia. In this study, we used a randomized complete block design (RCBD) and measured the Magnolia champaca height, root collar diameter, diameter at breast height, plant survival, root diameter, main root length, lateral root length, root coiling, root direction, and chlorophyll content. The soil samples were taken to study the effect of different mulching materials on soil characteristics. We also measured soil compaction, soil texture, soil colour, soil moisture content, soil organic carbon, total nitrogen, total sulphur, available phosphorus, and exchanged potassium. This study indicates that mulching had no significant effect on plant height, diameter breast height, root collar diameter, and chlorophyll content between treatments. Although mulching had a significant effect on root diameter, main root length, and root distributions among treatments while for lateral root length and root:shoot ratio did not show a significant effect among treatments. However, oil palm mulching treatment had a greater effect on plant height, root collar diameter, and diameter at breast height growth, among treatments. Mulching significantly affected soil pH, soil moisture content, total sulphur, and potassium exchange. In contrast, mulching did not significantly affect soil organic carbon, total soil nitrogen, and soil available phosphorus between treatments.

Nutrient suppression effect on growth and development of Ochroma pyramidale (Cav. ex Lam.) Urb. seedlings

Introduction: Ochroma pyramidale (Cav. ex Lam.) Urb. is a species with high potential for use in commercial reforestation. Knowledge of nutrient requirements in nursery increases the chances of success in the field by generating plants with adequate morphological and physiological characteristics. Objective: To identify the key nutrients for O. pyramidale growth in nursery and to characterize the associated visual symptoms of deficiency. Materials and methods: The design was completely randomized with 10 treatments: one treatment without fertilization, one treatment with complete fertilization (CF), and eight resulting from the CF treatment with suppression of N, P, K, Ca, Mg, S, B and cationic microelements (Mn, Fe, Cu and Zn). The effect of each treatment was determined by height, root collar diameter, aboveground dry biomass, root dry biomass, leaf area and relative growth rate. An analysis of variance and separation of means was performed using the Tukey's test (P < 0.05). Results and discussion: Nutrient suppression had significant effects (P < 0.05) on growth after six months in nursery. P was the most limiting element, followed by N. The other treatments showed no significant differences compared to the FC treatment. N suppression caused yellowing, and lack of P caused necrosis with subsequent death and detachment in leaves. B suppression showed no clear deficiency symptoms. Conclusion: O. pyramidale showed high nutrient uptake efficiency. Only N and P strongly limited its development, which represent the key nutrients for the species.

Seedling Growth of Tectona grandis using Different Potting Mixture

Aims: This study evaluated the influence of 11 potting media compositions on seedling growth and development of Tectona grandis. Study Design: The experiment was set up in a completely randomized design involving ten replicates. Place and Duration of Study: The study was carried out at the Department of Forestry and Wildlife Management Nursery, University of Port Harcourt, Rivers State, Nigeria, between April 2019 and April 2020. Methodology: Ten (10) seedlings per sowing media including topsoil, topsoil and cow dung (2:1, 3:1), topsoil and poultry dung (2:1, 3:1), topsoil and pig dung (2.1, 3:1), topsoil and sawdust (2.1, 3:1), topsoil and mushroom substrate (2.1, 3:1) were selected and transplanted into polybags. Growth parameters (seedling height, root collar diameter, leaf number and biomass (shoot dry weight (SDW), root dry weight (RDW) and total dry weight (TDW)) were determined and subjected to analysis of variance. Results: Seedlings of T. grandis displayed significant differences (p ≤ 0.05) in height, root collar diameter, leaf number and biomass. Among treatments, tallest seedlings were observed in mixture of topsoil and poultry dung (3:1), at months 1 to 3 and in mixture of topsoil and cow dung (3:1) at months 4 and 5, highest root collar diameter was observed in mixture of topsoil and poultry dung (3:1) and highest leaf number was recorded in mixture of topsoil and poultry dung (2:1 and 3:1) and topsoil and cow dung (2:1 and 3:1) at months 1 to 5. The highest SDW was evident in mixture of topsoil and poultry dung (2:1) while highest RDW and TDW were observed in mixture of topsoil and cow dung (3:1). Lowest height, diameter, leaf number and biomass were recorded in topsoil (control) at months 1 to 5. Conclusion: The results revealed that among the tested mixtures, topsoil and poultry dung and topsoil and cow dung mixtures were the best for seedlings growth of T. grandis.

The Effect of Seed Size on Germination and Seedling Growth in Sweet Chestnut (Castanea sativa Mill.)

The quantity and quality of seedlings in the nursery has an impact on the success of re-establishment and later growth. High germination rates enable a sufficient number of seedlings, and their quality is assessed using a number of parameters, including seedling height and root collar diameter. These parameters are influenced in some species by seed size, but the correlation between them is species-specific. The model species in this research was sweet chestnut (Castanea sativa Mill.), and seeds from 12 populations from two distinct biogeographical regions of Croatia were collected. We examined the influence of seed size on four parameters: germination rate, seedling height, root collar diameter and sturdiness quotient. Seed size has been shown to have a positive influence on both seedling height and root collar diameter, whereas no such correlation was noted for germination rate and sturdiness quotient. Significant differences in nut size and seedling growth parameters were found between the Mediterranean and continental populations, with higher values observed in the coastal Mediterranean populations. We concluded that seed origin and seed size have a significant impact on seedling growth and are important factors to consider when choosing seed material. Further nursery operations should consider seed origin and local environmental conditions when choosing seedlings for reforestation efforts and general forest operations.

Responses of the Physiological and Biochemical Characteristics of Alfalfa Roots with Different Root Collar Diameters to Low Temperatures Under Simulated Winter Irrigation

Background: Due to the frequent occurrence of extremely low temperatures in northern China, the problem of alfalfa mortality during overwintering requires urgent solutions to support the development of large-scale alfalfa production in the region. Understanding the effects of winter irrigation and the alfalfa root collar diameter on physiological and biochemical cold resistance mechanisms in alfalfa will be of great significance to finding such solutions.Methods: In this study, alfalfa roots with different root collar diameters (3.50±0.10 mm, 5.25±0.10 mm, 7.00±0.10 mm) were subjected to simulated winter irrigation (0 ml, 20 ml, 40 ml) and different low-temperature stress treatments (4°C, -10°C, -15°C, -20°C) in the laboratory. The relationships between alfalfa root collar activity, relative conductivity and the nonstructural carbon and nitrogen contents and antioxidant enzyme activity in the collar were explored.Results: Low-temperature stress was the most important factor causing significant changes in the physiological and biochemical indexes of the alfalfa root collar, followed by the root collar diameter. Low-temperature stress and the root collar diameter had significant effects on nonstructural carbon and nitrogen levels and enzyme activity (except POD activity) in alfalfa root collars, and winter irrigation had extremely significant effects on the nonstructural nitrogen contents of alfalfa root collars. The larger the diameter of the root collar was, the higher the soluble protein content and the stronger the SOD activity. Simulated winter irrigation increased the C/N ratio in the alfalfa root collars. The increases in nonstructural carbon content, C/N ratio and SOD activity in alfalfa root collars helped improve alfalfa cold resistance.Conclusions: Alfalfa resists low-temperature stress by adjusting the proportions of nonstructural carbon and nitrogen as well as the SOD activity in the root collar. Therefore, fertilization, early sowing and other management measures should be adopted to ensure healthy alfalfa growth and thereby increase the root collar diameter of alfalfa grown in cold regions in northern China. Moreover, timely supplementary irrigation to reach soil saturation in winter can play an important role in improving cold resistance in alfalfa.