Stem Number Research Articles

Noen nye funn av østlige belter og remutstyr fra sen vikingtid og tidlig middelalder i Norge

While belts and belt accessories have been a relatively minor theme for Viking Age research in Norway so far, unlike for instance in Sweden, new finds are changing the situation. This article deals with a particular type of strap accessories, namely so-called “oriental” mounts made from copper alloy, and originally produced mainly in present-day Russia and Ukraine. The author knows 26 such finds, most of them consisting of single mounts, and all of them resulting from metal-detecting. A number of finds stem from Northern Norway, where they seem, at least partially, to be another aspect of the already well-studied Eastern finds there. The majority of the new finds, however, have come to light in inland areas of eastern Norway. The latter area, in earlier times called “The Uplands” (Opplandene), seems to have had close connections both to Sweden and to areas further east in this period, as witnessed both by archaeological and written sources. It is suggested that the recent finds of “oriental” mounts represent, directly or indirectly, warriors that had spent time in the druzhinas of Ancient Rus’ rulers.

High beta diversity of gaps contributes to plot-level tree diversity in a tropical forest.

Canopy gaps are widely recognized as being crucial for maintaining the diversity of forest tree communities. But empirical studies have found mixed results because the differences in diversity between individual gaps and non-gaps are often small and statistically undetectable. One overlooked factor, however, is how small individual gap versus non-gap differences may accumulate across sites and potentially have a large effect on forest diversity at the plot scale. Our study investigated sapling richness, density, and composition in 124 treefall gaps, and 200 non-gap sites in the 50-ha tropical forest plot at Barro Colorado Island (BCI), Panama. Additionally, we analyzed species accumulation curves to understand how species richness increases with increasing stem numbers. We observed that sapling richness and density were only slightly higher in gaps 7 years after formation and statistically indistinguishable from non-gaps after 12 years. However, species accumulation curves across multiple gaps were substantially higher than those across non-gaps. Species composition showed small differences between individual gaps and non-gaps but differed significantly between collections of gaps and non-gaps. Specifically, 55 species specialized in 7-year-old gaps compared with 24 in non-gaps; of these, 23 gap-specialized species and zero non-gap species were pioneers. Our results indicate that tree species richness is higher in gaps because of both higher stem density and the presence of gap-specialized species. Our study has finally provided compelling evidence to support the idea that gaps enhance the overall diversity of tropical forest tree communities.

Drag coefficients and water surface profiles in channels with arrays of linear rigid emergent vegetation

Although vegetation in watercourses has an important ecological function, from a hydraulic point of view, it increases flow resistance, determinates higher water levels and generates a greater risk of flooding. In engineering practice, to determine water levels, the drag coefficient must be known, whose experimental values, in literature, are provided for uniform or quasi-uniform flow. In this paper, the expression of a drag coefficient, previously proposed by the authors for the case of emergent rigid vegetation arranged in a linear manner, was used to simulate experimental water surface profiles, employing the effective width for the first time. The formula was validated by simulating 26 experimental profiles observed at the University of Calabria, over 1100 points in total, plus 8 published in literature. In some of these applications, the vegetation density was much higher than that for which the drag coefficient expression was derived. For this reason, it is possible to consider a new, wider field of validity for it. The proposed equation is independent of the Reynolds stem number, so that it can be used in natural streams and rivers, provided that viscosity effects can be considered negligible. Finally, some comments are offered on the application of a new formula proposed in literature regarding the computation of the profile when downstream depth is taken as a boundary condition.

Canopy coverage of wheat measured with high accuracy using the HSV colour model and relative depth estimation model, MiDaS

ABSTRACT Canopy coverage calculated from 2D images effectively estimates several parameters, such as dry weight above the ground, stem number, and risk of lodging, without destroying the crops. This study aimed to clarify how to accurately calculate canopy coverage, regardless of environmental conditions, using various colour models and a relative depth estimation model, MiDaS. For wheat cultivated in 2022/23, the canopy coverage at the initiation of the stem elongation stage (CC30), calculated using only the HSV colour model, was overestimated because of the presence of weeds. However, when the heatmap generated using MiDaS was combined with the results extracted from the HSV colour model, it showed a CC30 similar to the accurate CC30 calculated by hand drawing, regardless of the wheat variety, sowing pattern, and location of the image taken, with an RMSE as low as 3.48. The CC30 calculated by combining the HSV colour model and MiDaS was significantly positively correlated with the number of stems, dry weight above ground, and nitrogen content above ground at the initiation of the stem elongation stage of ‘Sanukinoyume 2009’ grown in 2021/22 and 2022/23 (n = 72, r > 0.798). The combination of the HSV colour model and MiDaS effectively and accurately calculates canopy coverage regardless of environmental conditions and can be used for growth diagnosis and variable nitrogen fertiliser application after the initiation of the stem elongation stage.

Understanding the Impact of Zinc and Boron Applications on Growth and Yield Attributes in Potato

Research examines the impact of zinc (Zn) and boron (B) on the growth, and yield of potato plants. The screen house experiment used four treatments: T1 (Control), T2 (Zn 5g/L), T3 (B 2g/L), and T4 (Zn 5g/L + B 2g/L). Growth characteristics were evaluated, such as the emergence percentage, plant vigor, number of stem /meter2, plant height, and stem diameter. In addition, essential yield metrics such as number of tubers, tuber weight (g), dry matter content, and specific gravity were also assessed. The findings indicated that concurrent administration of T4 had a substantial positive impact on the plant's vitality, height, stem thickness, and stem density per square meter compared to the control group. This suggests a cooperative influence of these micronutrients on the growth of plant structures. However, in terms of yield qualities, the use of Zn alone T2 led to the greatest tuber weight, dry matter content, and specific gravity. Showing that Zn plays a crucial role in maximizing tuber growth and quality. The treatment T4 enhanced yield parameters compared to the control, but it did not exceed the effects of either Zn or B individually in T2 and T3. This emphasizes the intricate interaction between these nutrients. However, when it comes to maximizing yield attributes in potato cultivation, using Zn alone may be more successful. The results indicate that customizing the management of micronutrients could optimize the growth and output of potatoes, hence enhancing agricultural productivity. Additional research is advised to investigate the most effective dosages and combinations

Branching response to stem density and its impact on yield in hybrid potato grown from true seeds and seedling tubers

ContextHybrid potato crops can be grown from true potato seeds or from seedling tubers. True-seed-grown plants produce lower marketable tuber yield than seedling-tuber-grown plants, because of their low early vigour and distinct growth and development patterns, notably in term of main stem number and stem branching. These differences are pivotal for yield formation but their impacts on crop performance and yield are not well understood. ObjectivesWe quantified the differences between the propagule types (true seeds vs seedling tubers) in their branching responses to stem density and assessed to what extent these differences contribute to differences in crop development and tuber production. MethodsTwo field experiments were conducted in different years, planting transplants from true seeds and pre-sprouted seedling tubers from the same genotype, while controlling their stem density per unit area. Responses in stem branching and biomass partitioning to stem density were quantified on individual main stems, followed by an evaluation of the impact of these responses on crop performance. ResultsOn individual main stems in both propagule types, higher stem density decreased branch development, decreased the number of branches above- and belowground, resulted in shifts in aboveground branch distribution towards lower branching orders, and led to smaller tuber sizes. However, such branching responses were stronger in true-seed-grown plants than in seedling-tuber-grown plants. At crop level, differences between propagule types were significant in canopy duration, number of tubers, tuber size distribution and marketable yield, but there was no stem density effect. ConclusionOur results emphasized the differences between propagule types in branching and its impact on crop development and tuber yield, due to the absence of stem density effects. Propagule type effects could be attributed to intrinsic differences between propagule types in branching control, growth habit and source-sink relations. These effects are relevant for hybrid potato breeding and require further research. Management practices were partly responsible for year-to-year differences in branching and yield formation, which highlights their significance for hybrid potato production.

Anthroponics: Application and effects on growth of parsley, rhipsalis, coriander, and basil fed with urine fertiliser

Urine has emerged as a promising nutrient-rich waste stream suitable for plant fertigation. Biological nitrification in a membrane bioreactor offers an effective method for producing liquid fertiliser from urine, extracting essential nutrients into a final product. Despite the increasing interest in hydroponics and urban horticulture, research exploring the efficacy of urine-derived fertilisers remains scarce. This study employed three growing systems, including nutrient film technique open channels in outdoor setup, pot-drench under glasshouse conditions, and deep-water culture (DWC) under laboratory conditions to investigate the efficiency of urine-derived fertiliser compared to commercial fertilisers. The results demonstrated comparable growth responses in parsley, rhipsalis, coriander, and basil, as demonstrated by the analysis of several parameters including biomass, stem numbers and length, and nutritional composition in shoots and roots. In conclusion, urine-derived fertilisers showed promising potential as a sustainable alternative to synthetic fertilisers, laying the foundation for the development of a circular economy of nutrients in agriculture.

Brief cycling intervals incrementally increase the number of hematopoietic stem and progenitor cells in human peripheral blood.

Peripheral blood stem cell (PBSC) donation is the primary procedure used to collect hematopoietic stem and progenitor cells (HSPCs) for hematopoietic stem cell transplantation. Single bouts of exercise transiently enrich peripheral blood with HSPCs and cytolytic natural killer cells (CD56dim), which are important in preventing post-transplant complications. To provide a rationale to investigate the utility of exercise in a PBSC donation setting (≈3h), this study aimed to establish whether interval cycling increased peripheral blood HSPC and CD56dim concentrations to a greater degree than continuous cycling. In a randomised crossover study design, eleven males (mean ± SD: age 25 ± 7years) undertook bouts of moderate intensity continuous exercise [MICE, 30min, 65%-70% maximum heart rate (HRmax)], high-volume high intensity interval exercise (HV-HIIE, 4 × 4min, 80%-85% HRmax) and low-volume HIIE (LV-HIIE, 4 × 2min, 90%-95% HRmax). The cumulative impact of each interval on circulating HSPC (CD34+CD45dimSSClow) and CD56dim concentrations (cells/µL), and the bone marrow homing potential of HSPCs (expression of CXCR-4 and VLA-4) were determined. There was an increase in HSPC concentration after two intervals of LV-HIIE (Rest: 1.84 ± 1.55 vs. Interval 2: 2.94 ± 1.34, P = 0.01) and three intervals of HV-HIIE only (Rest: 2.05 ± 0.86 vs. Interval 3: 2.51 ± 1.05, P = 0.04). The concentration of all leukocyte subsets increased after each trial, with this greatest for CD56dim NK cells, and in HIIE vs. MICE (LV-HIIE: 4.77 ± 2.82, HV-HIIE: 4.65 ± 2.06, MICE: 2.44 ± 0.77, P < 0.0001). These patterns were observed for concentration, not frequency of CXCR-4+ and VLA-4+ HSPCs, which was unaltered. There was a marginal decrease in VLA-4, but not CXCR-4 expression on exercise-mobilised HSPCs after all trials (P < 0.0001). The results of the present study indicate that HIIE caused a more marked increase in HSPC and CD56dim NK cell concentrations than MICE, with mobilised HSPCs maintaining their bone marrow homing phenotype. LV-HIIE evoked an increase in HSPC concentration after just 2 × 2-minute intervals. The feasibility and clinical utility of interval cycling in a PBSC donation context should therefore be evaluated.

Evaluation and selection of alfalfa genotypes for tolerance to aluminium toxic stress.

Alfalfa is one of the most important and the most cultivated crop due to its high nutritive quality and yield, but adaptation of alfalfa genotypes differ in terms of mobile aluminium stress in the soil. The aim of this study was to evaluate the tolerance to mobile Al concentrations in the laboratory and in the naturally acidic soil and select the promising genotypes based on agro-biological traits. In 2019, a laboratory experiment was conducted at the Institute of Agriculture of LAMMC. The experiment in the acidic soil with different mobile Al concentrations was conducted at the Vėžaičiai Branch of LAMMC. In 2020, the crops of alfalfa genotypes (11 cultivars and 3 populations) were established on Balthygleyic Dystric Retisol. The agro-biological traits were assessed during the 2021-2022 season. The tolerance index of hypocotyls and roots was evaluated using the filter-based screening method at different AlCl3 (0.0-64 mM) concentrations. The study results of the filter-based screening method showed that the genotype Žydrūnė, Malvina, Jõgeva 118, Skriveru, and 3130 were the most tolerant ones and the hypocotyl tolerance index of these genotypes was higher compared to medium tolerant genotypes Birutė, PGR12489, Europe and AJ2024 at 8, 16, 32 and 64 mM AlCl3 concentrations. The hypocotyl and root tolerance index of medium tolerant genotypes was higher compared to a sensitive genotype PGR10249 at 8 and 16 mM AlCl3. The study of cluster analysis with mobile Al 0.0-65.0 mg kg-1 showed that the genotypes Žydrūnė, Europe, AJ2024 and 3130 were the best in terms of wintering and spring regrowth, the cultivar Malvina had the best value of wintering, height before flowering and stem number, the cultivar Birutė had the best value of spring regrowth, height before flowering and seed yield, and the cultivar Skriveru had the best value of spring regrowth, height before flowering, stem number and seed yield.

Prolonged exposure to hypergravity increases number and size of cells and enhances lignin deposition in the stem of Arabidopsis thaliana.

We have performed a lab-based hypergravity cultivation experiment using a centrifuge equipped with a lighting system and examined long-term effects of hypergravity on the development of the main axis of the Arabidopsis (Arabidopsis thaliana (L.) Heynh.) primary inflorescence, which comprises the rachis and peduncle, collectively referred to as the main stem for simplicity. Plants grown under 1 × g (gravitational acceleration on Earth) conditions for 20-23 days and having the first visible flower bud were exposed to hypergravity at 8 × g for 10 days. We analyzed the effect of prolonged hypergravity conditions on growth, lignin deposition, and tissue anatomy of the main stem. As a result, the length of the main stem decreased and cross-sectional area, dry mass per unit length, cell number, and lignin content of the main stem significantly increased under hypergravity. Lignin content in the rosette leaves also increased when they were exposed to hypergravity during their development. Except for interfascicular fibers, cross-sectional areas of the tissues composing the internode significantly increased under hypergravity in most types of the tissues in the basal part than the apical part of the main stem, indicating that the effect of hypergravity is more pronounced in the basal part than the apical part. The number of cells in the fascicular cambium and xylem significantly increased under hypergravity both in the apical and basal internodes of the main stem, indicating a possibility that hypergravity stimulates procambium activity to produce xylem element more than phloem element. The main stem was suggested to be strengthened through changes in its morphological characteristics as well as lignin deposition under prolonged hypergravity conditions.

Association and Path Coefficient Analysis Studies in Potato (Solanum tuberosum L.) Genotypes at Adet, Northwestern Ethiopia

The experiment was conducted during main rain fall season from June to October, 2018 in Adet, Ethiopia with the objective of estimating the correlation and identifying the direct and indirect effect of yield contributing traits on potato crop. 36 potato genotypes were evaluated in simple lattice design in two replications. The analysis of variance revealed that highly significant (p&lt;0.001) difference among potato genotypes for all traits except average stem number. Total tuber yield was positively correlated with days to maturity, plant height, average stem number, marketable, unmarketable, total tuber number and marketable yield while it was negatively correlated with late blight severity percentage at both phenotypic and genotypic level. High correlation was observed between total tuber yield and marketable tuber yield (rp=0.982 and rg=0.986) followed by total tuber number (rp=0.735 and rg=0.789), and marketable tuber number (rp=0.700 and rg=0.737). Days to flowering, days to maturity, average stem number, marketable and unmarketable tuber number, starch content percentage, average tuber weight, and unmarketable tuber yield had positive direct effect on the total tuber yield at both genotypic and phenotypic level. Highly direct effect on total tuber yield was observed by marketable and unmarketable tuber number (3.65 and 1.17 respectively) and average tuber weight (0.56). Therefore, traits with significant positive correlated and direct effect on total tuber yield such as days to maturity stem number, marketable tuber number, marketable tuber yield and average tuber weight should be considered in selection criteria for enhancing tuber yield in potato.

ESTABLISHMENT OF PHENOTYPIC VARIABILITY AND CORRELATIONS OF SEED YIELD AND YIELD RELATED TRAITS IN ALFALFA (Medicago sativa L.) CLONAL PROGENIES

The aim of present study was to evaluate phenotypic variability of seed yield and yield-related traits and to establish the relationships among them at eleven alfalfa clonal progenies. The study was conducted in experimental field at Institute of Agriculture and Seed Science Obraztsov chiflik - Ruse under conditions of open pollination (polycross), from 2014 to 2016. The traits plant seed yield, plant height, generative stem number, inflorescence number, pod number, seed number and 1000-seed weight were evaluated. The factors year, genotype and year x genotype interaction had a significant influence on all morphological and generative traits. There was wide range of variability for all analized traits between progenies and over study period. PM30 progeny showed superior scores regarding all traits studied and four progenies distinguished with high phenotypic expression of seed yield, pod number, seed number and 1000-seed weight. These progenies are valuable germplasm source to be used in further breeding to develop a new synthetic alfalfa variety with stable seed yield. It was found seed yield strongly and positively correlated with plant height, seed number per pod and pod number per inflorescence, wtich suggest that selection for improving alfalfa seed yield may be performed directly through selection on these three traits.

Effect of coffee husk biochar and inorganic NP fertilizer on soil properties, growth and yield of potato (Solanum tuberosum L.) on acidic soil of southwest Ethiopia

Soil acidity and low soil fertility due to nutrient leaching coupled with low inorganic fertilizer usage is a major cause of low crop yields across Southwest Ethiopia. Recently, biochar potential to improve soil fertility has gained significant attention but there are limited studies on the use of biochar in combination with inorganic fertilizers. A field experiment was, therefore, conducted to investigate the effect of combined application of biochar and inorganic NP nutrient on soil physicochemical properties, growth and yield of potato in Andiracha district, Southwestern Ethiopia. The experiment was laid out in randomized complete block design (RCBD) and replicated three times. The treatment consisted of four levels of biochar rates (0, 2.5, 5 and 7.5 t ha−1) and four fertilizer rates of (0, 75,100 and 125% of recommended N P rates). Data were analyzed using SAS version 9.3 Software. Analysis of variance showed that combined application of biochar and inorganic NP fertilizer had highly significant (p < 0.01) effect on days to flowering, stem number, plant height, total leaf area, total dry biomass, marketable tuber number per hill and harvest index and significant (p < 0.05) effect on marketable tuber weight and total tuber weight ha−1. Combined application of 7.5 ton ha−1 biochar with 165 kg N and 60 kg P ha−1 resulted highest tuber yield (42.64 t ha−1), that increased yield by 28.99% compared with recommended NP fertilizer alone (165 kg N ha−1 and 60 kg P ha−1), and by 76.6% compared to the control. The increase was mainly attributed to the improvement in soil physico-chemical properties especially soil pH, CEC, organic matter, total N and available P which is a reflection of increase in soil fertility. Consequently, it was determined that the best course of action for potato production in the area was to apply 7.5 tons of biochar ha−1 together with 165 kg N and 60 kg P ha−1. Therefore, the study recommends adoption of low cost biochar production techniques and capacity building to ensure satisfactory knowledge of biochar use and its adoption by potato growers for soil fertility management and enhanced crop productivity.

Variations on the Choi–Jamiołkowski isomorphism

The Choi–Jamiołkowski isomorphism is an essential component in every quantum information theorist’s toolkit: it allows to identify linear maps between two quantum systems with linear operators on the composite system. Here, we analyse this widely used gadget from a new perspective. Namely, we explicitly distinguish between its kinematical and dynamical properties, that is, we study the isomorphism on two different levels: Jordan algebras and the different C∗ -algebras they arise from, which are distinguished by their order of composition. A number of important and novel insights stem from our analysis. We find that Choi’s theorem, which asserts that Choi’s version of the isomorphism (Choi 1975 Lin. Alg. Appl. 10 285) further maps the positive cone of completely positive linear maps (such as quantum channels) to the cone of positive linear operators (such as quantum states) on the composite system, crucially depends on the dynamical structure in C∗ -algebras. We explain in detail how this dependence gives rise to the mismatch between the basis-dependence of Choi’s version of the isomorphism, and the basis-independent version by Jamiołkowski (1972 Rep. Math. Phys. 3 275). We then overcome this subtle but pervasive issue in a number of ways: first, we prove a version of Choi’s theorem for Jamiołkowski’s isomorphism, second, we define a basis-independent variant of Choi’s isomorphism and, third, by making explicit the dynamical distinction between Jordan and C∗ -algebras, we combine the different variants of the isomorphism into a unified description, that subsumes their individual features. We also embed and interpret our results in the graphical calculus of categorical quantum mechanics.

Dynamics of tree stems and biomass in old‐growth and secondary forests along gradients in liana dominance, elevation and soil

Abstract Lianas, or woody vines, are key components of many tropical forests and can have substantial impacts on the dynamics and functioning of these important ecosystems. Their competition with trees for resources, in particular light, can hamper the recovery of forests from disturbances. Yet, it is unclear how forest disturbance interacts with liana–tree ratio (LTR), topography and soil properties to shape tree dynamics and the trajectories of forest succession. Using temporal data from the Kilombero Valley and the Udzungwa Mountains of Tanzania, we demonstrate how the dynamics of tree stems and biomass vary between secondary and old‐growth forests with changes in the dominance of lianas and environmental gradients. Greater tree recruitment and mortality in secondary forests compared with old‐growth forests suggested rapid regeneration processes and faster turnover. However, no significant differences were found in the net annual changes in the number or biomass of trees between secondary and old‐growth forests. Our findings also showed that higher LTRs were positively associated with stem mortality but also with tree biomass growth, indicating a nuanced ecological role of lianas in forest ecosystems, which warrants further investigation to fully understand the causal factors at play. Net changes in tree stem numbers decreased significantly with elevation, implying climatic constraints on forest regeneration at higher elevations. Soil cation exchange capacity and organic carbon were found to significantly influence tree stem recruitment and net change in abundance, although their effects on biomass remained unclear. Synthesis: Our findings indicate that the recovery of tropical forests from disturbance in terms of the number and biomass of tree stems may be predictable along environmental gradients. These insights have the potential to broaden our capacity to develop more nuanced strategies that identify when and where tropical forests may require restoration interventions, with a focus on structural recovery.

Effect of High-Tunnel and Open-Field Production on the Yield, Cannabinoids, and Volatile Profiles in Industrial Hemp (Cannabis sativa L.) Inflorescence.

This study discovered the impact of high-tunnel (i.e., unheated greenhouse) and open-field production on two industrial hemp cultivars (SB1 and CJ2) over their yield parameters, cannabinoid development, and volatile profiles. Development of neutral cannabinoids (CBD, THC, and CBC), acidic cannabinoids (CBDA, THCA, and CBCA), and total cannabinoids during floral maturation were investigated. The volatile profiles of hemp flowers were holistically compared via HS-SPME-GC/MS. Findings indicated a high tunnel as an efficient practice for achieving greater total weight, stem number, and caliper, especially in the SB1 cultivar. Harvesting high-tunnel-grown SB1 cultivars during early flower maturation could obtain a high CBD yield while complying with THC regulations. Considering the volatile profiles, hemp flowers mainly consisted of mono- and sesquiterpenoids, as well as oxygenated mono- and sesquiterpenoids. Volatile analysis revealed the substantial impact of cultivars on the volatile profile compared to the production systems.

Birch distribution and changes in stand structure in Sweden’s young forests

ABSTRACT Silver birch (Betula pendula Roth) and downy birch (Betula pubescens Ehrh.) are the two most common broadleaf species in Sweden, together making up approximately 12% of the standing timber volume. The two birch species are usually not distinguished in practice, although they tend to differ in terms of volume production, timber quality, and site preferences. To map the proportion of the two birch species in Sweden’s young forests, we used survey data from 123 stands 6–7 years after clearfelling, and data from Sweden’s meteorological and hydrological institute. We also examined Sweden’s young forests in terms of area, volume, and stem density between 1983 and 2021, using national forest inventory data. Proportions of the two birch species varied significantly across Sweden, and the average temperature sum over the first five years after clearfelling explained 72% of the variation. There was no significant change in area of forest classified as young forest in Sweden, over the last four decades, although there was a significant increase in volume and stem density in Sweden’s young forests, with birch making up most of the increase in stem numbers.

Humic acid enriched with urea and NPK factory by-products promoted the growth and yield of Saccharum officinarum L.

Nutrient uptake efficiency in sugarcane (Saccharum officinarum L.) must be increased using organic matter to restore soil fertility, resulting in greater productivity. The humic substance is a complex organic material that is excellent for overcoming this challenge. This study aimed to determine the effect of the humic acid enriched by liquid urea by-product (PSUC) and liquid NPK by-product (PSNC) application on the growth and productivity of sugarcane. The experiment was conducted from October 2021 to September 2022 on PT RNI plantation land, Jatitujuh, Majalengka. The research was arranged in a completely randomized (CRD) using two different humic acid product prototypes (PSUC and PSNC) with two evaluation times, a screening and a semi-pilot scale. Solid humic at a dose of 15 Kg ha⁻¹ was applied by mixing it with inorganic fertilizers, while liquid humic at a total dose of 15 L ha⁻¹ was applied by foliar spray technique at 1, 2, and 3 months after planting (MAP). The results showed that applying humic acid PSUC and PSNC enhanced sugarcane shoot growth, segmented stem number, and diameter. In addition, it could consistently promote sugarcane yields on the semi-pilot scale up to 19.18% and 24.26% under humic acid PSUC and PSNC treatments, respectively. Therefore, both in the screening and semi-pilot evaluation, the solid and liquid humic acid PSUC and PSNC applied simultaneously are potential organic materials to enhance sugarcane growth and yield.

The Effects of Different GA3 and Mycorrhiza Dosages on Mini Tuber Production in Potatoes

This study was conducted in 2017 under greenhouse conditions using selected four different potato clones to determine the effects of different doses of GA3 and arbuscular mycorrhizal fungus on mini tuber production. The research, carried out in a randomized complete block design with three replications, applied GA3 doses of 0, 5, 10, and 15 ppm, and mycorrhizal inoculat doses of 0, 500, 1250, and 2000 mg/100 tubers. Parameters including emergence time, plant height, main stem number, tuber number, average tuber weight, tuber size distribution (&gt;45 mm, 28-45 mm, &lt;28 mm), and maturity period were examined. The effect of GA3 application on all investigated parameters except the number of main stems was significant, statistically. The highest mini tuber number (9.1 tubers) and mini tuber yield (408.4 g/pot) were obtained from the application of 15 ppm GA3, while the highest average mini tuber weight (46.74 g) was obtained from the control group. In mycorrhizal applications, the highest tuber number was obtained at a dose of 500 mg/100 tubers, and the highest mini tuber weight and yield were obtained at a dose of 1250 mg/100 tubers. As a result of the study, it was determined that the application of 15 ppm GA3 is suitable due to its positive effect on mini tuber multiplication, and the mycorrhizal application at a dose of 500 mg/100 tubers is appropriate due to its positive effect on increase of tuber number.

Structural and Successional Dynamics of Old-Growth Mixed Oak Forests in the West Qinling Mountains

Understanding the composition and structure of forest trees is crucial to comprehending the properties and functions of forests. It also helps in implementing effective management strategies for sustainable resource utilization. Our study analyzed the structural dynamics of the old-growth mixed oak forests in the Xiaolongshan Forest region, focusing on three long-term monitoring plots (A, B, C). We examined the tree species composition, diameter distribution, mortality, and recruitment dynamics of different successional species groups, as well as the spatial distribution patterns of living and dead trees, with surveys conducted every five years. The findings indicate: (1) Plot A experienced a decline in stand density and species diversity during the survey period, with the Importance Value Index (IVI) of pioneer successional species continually decreasing in plots B and C. (2) The tree diameter distribution structure in plot A significantly differed from other plots, showing notable change between 2007 and 2012. (3) All plots exhibited lower, well-balanced community-level demographic parameters based on stem number, but a higher recruitment rate for later successional species groups based on basal area. (4) Dead individuals in plot A had a slight clustering distribution, while the other plots showed a random distribution. We conclude that the individual growth rate significantly impacts the dynamics of the natural Quercus aliena var. acuteserrata forest, with pioneer species groups being gradually replaced by early or late-successional species groups in the succession process.