Seedling Height Research Articles

Detection of Growth Change of Young Forest Based on UAV RGB Images at Single-Tree Level

With the rapid development of Unmanned Aerial Vehicle (UAV) technology, more and more UAVs have been used in forest survey. UAV (RGB) images are the most widely used UAV data source in forest resource management. However, there is some uncertainty as to the reliability of these data when monitoring height and growth changes of low-growing saplings in an afforestation plot via UAV RGB images. This study focuses on an artificial Chinese fir (Cunninghamia lancelota, named as Chinese Fir) young forest plot in Fujian, China. Divide-and-conquer (DAC) and the local maximum (LM) method for extracting seedling height are described in the paper, and the possibility of monitoring young forest growth based on low-cost UAV remote sensing images was explored. Two key algorithms were adopted and compared to extract the tree height and how it affects the young forest at single-tree level from multi-temporal UAV RGB images from 2019 to 2021. Compared to field survey data, the R2 of single saplings’ height extracted from digital orthophoto map (DOM) images of tree pits and original DSM information using a divide-and-conquer method reached 0.8577 in 2020 and 0.9968 in 2021, respectively. The RMSE reached 0.2141 in 2020 and 0.1609 in 2021. The R2 of tree height extracted from the canopy height model (CHM) via the LM method was 0.9462. The RMSE was 0.3354 in 2021. The results demonstrated that the survival rates of the young forest in the second year and the third year were 99.9% and 85.6%, respectively. This study shows that UAV RGB images can obtain the height of low sapling trees through a computer algorithm based on using 3D point cloud data derived from high-precision UAV images and can monitor the growth of individual trees combined with multi-stage UAV RGB images after afforestation. This research provides a fully automated method for evaluating the afforestation results provided by UAV RGB images. In the future, the universality of the method should be evaluated in more afforestation plots featuring different tree species and terrain.

Utilizing Compost Soil Conditioner in Beach Sand Soil as a Palm Oil (Elaeis guineensis Jacq) in Pre-nursery Media

The objective of this study was to assess the effect of the type and dose of compost on the growth of oil palm seedlings in pre nursery with coastal sandy soil. The other objective is to know the effect of the type of compost on the growth of oil palm seedlings in pre nursery with coastal sandy soil. Lastly, the study examines the right dose of compost that provides the best growth of oil palm seedlings in pre nursery with coastal sandy soil. The experimental design was set in a factorial completely randomized design (CRD) consisting of two factors from April to June 2020 at the Tridharma Research Station Faculty of Agriculture, INSTIPER. The first factor is the type of compost which consists of 2 levels, Lamtoro compost, and vermicompost. The second factor is the dose of compost consisting of 4 levels: control (without compost), 50 gr compost/polybag, 75 gr compost/polybag, and 100 gr compost/polybag. The research data were analyzed using analysis of variance (α =0,05), and if there was a significant effect, it was continued with the Duncan multiple range test ( α = 0,05). Parameters observed included seedling height, total leaf, leaf width, stem diameter, shoot dry weight, root dry weight, root length, and total roots. The results showed that no combination of types and doses of compost significantly affected the growth of oil palm seedlings in pre-nursery. Using vermicompost can significantly increase oil palm seedlings' leaf area and root dry weight. Using compost at a dose of 50 g/polybag increased seedling height, stem diameter, and root dry weight in pre-nursery of oil palm seedlings.

Evaluating the Effects of Biochar and Organic Soil Amendments on Seedling Development of Annona muricata. Linn

The importance of appropriate growth media for propagation of Annona muricata seedlings cannot be over emphasized. An experiment was conducted to investigate the effects of biochar and organic soil amendments on seedling development of Annona muricata using different potting media. The treatments were Control; Topsoil only (T0), Mineralized goat dung (T1), Mineralized saw dust (T2), Mineralized poultry dropping (T3) and Mineralized biochar (T4). The experiment was laid out in Completely Randomized Design (CRD). Parameters accessed include seedling height (cm), collar diameter (cm) and number of leaves. The data collected were subjected to analysis of variance and significant means were separated using Duncan multiple range test at 0.05 significant level. Result shows that Mineralized biochar had the best performance in seedling height, collar diameter and number of leaves with mean values of 26.703±1.5488, 4867±0.22904 and 4.4451±1.55031 respectively. While the least performance in seedling height, collar diameter and number of leaves was recorded in the control with mean values of 19.986±1.1265, 0.3230±0.17363 and 3.6765±1.14724 respectively. However, there were significant differences in seedling heights and collar diameter among the treatment types at 5% level of probability, but the number of leaves was not significant. Annona muricata seedlings thrives excellently in biochar potting media. Hence, the use of biochar potting media should be adopted as the best growth media for early growth and development of Annona muricata seedlings.

Design of Non-Thermal Plasma Alfalfa Seed Vigor Enhancement Device and Study of Treatment Effect

Highlights An effective seed treatment method is provided. Three generations of field growth trials were conducted. We Investigated the effects of low-temperature plasma treatment on the biological characters and yield components. Abstract. An atmospheric pressure, low-temperature dielectric barrier discharge (DBD) plasma seed treatment device was developed for plasma seed treatment. The device worked continuously on alfalfa seeds and evenly distributed the seeds in a plasma discharge range. The processing time, voltage amplitude, and frequency were adjustable. The device was used to study the effect of DBD plasma treatment at different voltages and times on alfalfa seed germination using untreated alfalfa seeds as the control (CK). The results showed that the DBD plasma treatment of alfalfa seeds promoted seed germination and seedling growth, and the optimal discharge conditions were a discharge voltage of 11 kV and a discharge time of 40 s. Compared with CK, the germination potential and germination rate increased by 12.49% and 18.08%, respectively. After treatment using the optimal discharge time, the germination potential, germination rate, dry weight, and seedling height increased by 9.9%, 16.1%, 15%, and 32.9%, respectively, compared with CK. The Scanning Electron Microscope images of the seed epidermis treated with 11 kV and 40 s plasma showed that the surface of alfalfa seeds was etched. Different doses of discharge radiation had different effects on physiological processes in seeds, and their sensitivity to plasma discharge was different. In a certain range, the germination rate, germination potential, fresh weight, dry weight, root length, and seedling height of alfalfa seeds improved to different degrees under different discharge voltages and times. Plasma has a good application prospect for improving the growth of alfalfa seeds. Keywords: Alfalfa, Dielectric barrier discharge plasma, Germination, Seed treatment device, Seedling growth.

Growth of tomato and cucumber seedlings under different light environments and their development after transplanting.

Selecting suitable light conditions according to the plant growth characteristics is one of the important approaches to cultivating high-quality vegetable seedlings. To determine the more favorable LED light conditions for producing high-quality tomato and cucumber seedlings in plant factories with artificial light (PFALS), the growth characteristics of tomato and cucumber seedlings under seven LED light environments (CK, B, UV-A, FR, B+UV-A, UV-A+FR, and B+FR) and the development of these seedlings after transplanting into a plastic greenhouse were investigated. The results showed that the seedling height and hypocotyl length increased in treatments with far-red light supplementation (FR, UV-A+FR, and B+FR), but decreased in the B treatment, in both varieties. The seedling index of tomato seedlings increased in the B+UV-A treatment, while that of cucumber seedlings increased in the FR treatment. After transplanting into a plastic greenhouse, tomato plants that radiated with UV-A had greater flower numbers on the 15th day after transplanting. In cucumber plants of the FR treatment, the flowering time was significantly delayed, and the female flower exhibited at a lower node position. By using a comprehensive scoring analysis of all detected indicators, light environments with UV-A and FR were more beneficial for improving the overall quality of tomato and cucumber seedlings, respectively.

Gibberellic acid in the emergence and early development of star fruit seedlings

Star fruit (Averrhoa carambola L.) is an exotic fruit originating in Southeast Asia and has seeds with low germination. The objective was to evaluate the effect of gibberellin on the emergence and initial development of star fruit seedlings. The seeds were removed from the fruits and washed in running water, and placed in gibberellin solution 1,000 mg.L-1, 2,000 mg.L-1, 3,000 mg.L-1, 4,000 mg.L-1 and pure water as a control. for 30 minutes. Sowing was carried out by placing 1 seeds per 280 mL tube in a substrate containing ravine soil + tanned manure (3:1) in a randomized block experimental design. Thirty days after the emergence of the first seedling, the percentage of emergence, emergence speed index and mean emergence time were evaluated. Ninety days after the emergence of the first seedling, the seedling height, collar diameter, number of leaves, root length were evaluated; green and dry mass of the leaves, green and dry mass of the roots. The star fruit seed has a low percentage of germination, with low emergence rates, and the use of gibberellin was efficient to increase and accelerate emergence, showing a positive response to the variables plant height, number of leaves, stem diameter and length of the seed. source. The treatment with gibberellic acid had a positive effect on the emergence and development of star fruit seedlings, and on the mass production of leaves and roots, with the concentration of 1,000 mg.L-1 showing the best results.

东祁连山灌丛凋落叶水浸提液对垂穗披碱草种子萌发和幼苗生长的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 东祁连山灌丛凋落叶水浸提液对垂穗披碱草种子萌发和幼苗生长的影响 DOI: 10.5846/stxb202203160648 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金(32060269);草地农业生态系统国家重点实验室开放基金课题 Effects of leaf litter aqueous extract on seed germination and seedling growth of Elymus nutans in Eastern Qilian Mountains Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:为了解灌丛凋落叶在灌草群落结构维持中可能存在的潜在化感作用,以东祁连山3种优势灌木和灌下优势草种垂穗披碱草(Elymus nutans)为供试材料,分析了不同浓度(0.01 g/L、0.025 g/L、0.05 g/L、0.075 g/L、0.1 g/L)的金露梅(Potentilla fruticosa)、川滇柳(Salix rehderiana)、头花杜鹃(Rhododendron capitatum)及灌间草本的凋落叶水浸提液,对垂穗披碱草种子萌发、幼苗形态和生理指标的影响。结果表明:(1)垂穗披碱草种子发芽率与发芽势在金露梅与川滇柳凋落叶浸提液处理下呈"低促高抑"的浓度效应,在灌间草本凋落叶浸提液处理时表现为先升后降,而头花杜鹃凋落叶浸提液处理时均下降,并在浓度超过0.075 g/L时种子不发芽。(2)灌丛凋落叶浸提液对垂穗披碱草幼苗根长与干重均表现出抑制作用,且随浓度增大而增强;金露梅、川滇柳与灌间草本凋落叶浸提液对垂穗披碱草幼苗苗高表现出"低促高抑"的浓度效应;而头花杜鹃凋落叶浸提液处理对垂穗披碱草幼苗鲜重与苗高均呈抑制作用。(3)垂穗披碱草幼苗CAT、SOD活性随着浸提液浓度升高均表现出先升后降的变化趋势;可溶性糖与可溶性蛋白在灌丛凋落叶浸提液浓度低于0.075 g/L时含量较高;MOD含量在金露梅凋落叶浸提液处理下随浓度升高而持续升高,而在川滇柳与灌间草本凋落叶浸提液处理下呈先升高后降低的趋势。综合来看,灌丛凋落叶浸提液对垂穗披碱草的化感作用由大到小依次为:头花杜鹃、川滇柳、灌间草本、金露梅,其中头花杜鹃对灌下草本植物影响较大,凋落叶化感作用是影响该地区灌草系统群落分布及灌草结构的重要因素。 Abstract:To understand the potential allelopathy of shrub litter in the maintenance of shrub-grass community structure, three dominant shrub species and the dominant herbaceous species Elymus nutans in Eastern Qilian Mountains were used as experimental materials. This paper analyzed the effects of Potentilla fruticosa, Salix rehderiana, and Rhododendron capitatum with different concentrations (0.01 g/L, 0.025 g/L, 0.05 g/L, 0.075 g/L, 0.1 g/L) of water extracts from the shrub leaf litter and herbs litter between shrubs on seed germination, seedling morphology and physiological indexes of E. nutans. The results are as follows: (1) The germination rate and germination potential of E. nutans seeds showed a concentration effect of "low promotion and high inhibition" under the treatment of leaf litter extract of P. fruticosa and S. rehderiana. Under the treatment of litter extract of herbaceous, the germination rate and germination potential were firstly increased and then decreased. Under the treatment of leaf litter extract of R. capitatum, the germination rate and germination potential were decreased, and the seeds did not germinate when the concentration exceeded 0.075 g/L. (2) The leaf litter extract of shrub species inhibited both the root length and dry weight of E. nutans seedlings, and it increased with the increase of concentration. The concentration effects of P. fruticose, S. rehderiana and herbaceous under leaf litter extracts on E. nutans seedling height showed "low promotion and high inhibition". R. capitatum litter extract inhibited the fresh weight and seedling height of E. nutans seedlings. (3) The activities of catalase and superoxide dismutase of E. nutans seedlings showed a trend of first increasing and then decreasing with the increase of the concentration of the extract. The contents of soluble sugar and soluble protein were higher when the concentration of litter extract was lower than 0.075 g/L. The content of malondiadehyde continued to increase with the increase of the concentration under P. fruticose leaf litter extract treatment, while it showed a trend of first increasing and then decreasing under S. rehderiana and herbaceous under leaf litter extract treatments. On the whole, the allelopathic effect of leaf litter extract from shrub on E.nutans in descending order: R. capitatum, S. rehderiana, herbaceous plants and P. fruticose, among which R. capitatum had a greater impact on the herbaceous plants under shrub canopy, and allelopathy of leaf litter had a greater impact on the distribution of shrub-grass system and the structure of shrub-grass community. 参考文献 相似文献 引证文献

Uticaj bakterijskih tretmana na morfološke osobine jednogodišnjih sadnica hrasta kitnjaka dve srpske provenijencije

Plant growth promoting bacteria present a diverse group of bacteria with wide applicative potential in seedling production, especially in referring to the Green agenda concept. The effect of 2 bacterial species on one-year-old sessile oak seedling's height, root collar diameter, and their ratio was studied. Oak plants were from 2 provenances - Avala and Košutnjak. The most significant influence on measured traits in Avala had treatment with Pseudomonas koreensis, and in Košutnjak, with Viridibacillus arvi. However, a two-way analysis of variance showed no statistical significance of provenance effect and bacterial treatment on measured traits. The research needs to be repeated on a greater number of individuals in order to confirm the results since the bacteria manifested their PGP potential in vitro.

Semente de milho crioula promove incremento nos aspectos produtivos e nutricionais da forragem hidropônica

ABSTRACT The aimed of this study to assess the productivity and nutritional characteristics of hydroponic corn forage derived from bico de ouro creole seeds and AL-Bandeirante. Two treatments (T), each representing a corn seed variety, were randomly allocated to beds filled with a wood sawdust substrate: T1 (n=5) - bico de ouro creole seed variety, and T2 (n=5) - AL-Bandeirante hybrid seed variety. On the 13th day, forage was collected to assess seedling biometry, green and dry mass production, and bromatological analyses. The data were subjected to statistical analysis, with a 5% significance level. The creole seed variety yielded higher seedling height (17.53 cm), root length (10.19 cm), stem (5.37 cm), leaf (12.17 cm), and greater production of green mass (7.22 kg/m²) and dry matter (2.05kg/m²) (P<0.05). The AL-Bandeirante corn forage had higher dry matter content (39.18%), mineral matter (2.33%), non-fiber carbohydrate (31.88%), and estimated total digestible nutrients (68.14%) (P<0.05), while the creole corn forage had higher organic matter content (99.45%), ethereal extract (19.53%), neutral detergent fiber (45.56%), and cellulose (15.46%) (P<0.05). Crude protein, acid detergent fiber, and lignin were similar between the treatments (P>0.05). Despite the AL-Bandeirante variety yielding a higher concentration of certain nutrients, its forage productivity was significantly low. Therefore, under the conditions of this study, the use of the creole seed variety is recommended.

Screening of Promising Rootstocks Against Phytophthora Root Rot in Citrus

Citrus root rot caused by Phytophthora parasitica var. nicotianae is the most damaging disease in citrus cultivation in Maharashtra’s Vidarbha region. To overcome the damage caused by this disease, tolerant/resistant rootstocks must be selected. In present study, twelve varied root stocks were tested in sick pot condition to determine tolerance/resistance against Phytophthora nicotianae during 2020-21 by inoculating 6 month old seedlings with a 20 ml spore suspension (108 cfu/ml) of P. nicotianae per pot. Disease incidence, feeder root rot index, percent leaf fall and Phytophthora population density were all assessed six weeks after inoculation. The response of root stocks to the tested pathogen varied. The minimum per cent root rot incidence (4.44 %) and feeder root rot (0.63) was observed in Alemow (C. macrophylla) while maximum root rot incidence (28.89%) and feeder root rot (3.20) was noticed in susceptible check Rough lemon (Citrus jambheri). Rangpur lime Akola had the highest seedling height (28.43 cm), while root stock CRH-12 had the lowest (21.07 cm). The results showed that there were no significant differences in the population density of Phytophthora cfu/cc soil in the tested root stocks. It is thought that the rootstock Alemowisinvolvedin citrusplant tolerantto P. nicotianae.

Characterization and evaluation of putative mutant populations of polyembryonic mango genotype Nekkare for dwarfing rootstock traits

Availability of dwarfing rootstocks is an important pre-requisite for improving productivity of mango orchards in India as it facilitates high density planting as well as impart uniformity within an orchard. An attempt was made to induce variability in polyembryonic mango genotype Nekkare for dwarfness by treating kernels with different doses of gamma radiation ranging from 15 to 35 Gy. Irradiation created significant variation in plant height, stem girth, number of nodes, inter-nodal length, number of leaves, leaf blade length and leaf blade width. The highest reduction in seedling height along with highest variation was observed at 35 Gy where the seedling height ranged from 11.50 to 33 cm with a mean of 23.12 cm as compared to mean plant height of 44.55 cm in control ranging from 33.50 to 56 cm. Further, the effect of irradiation on stomatal parameters was also investigated and the highest stomatal length and width was recorded at 15 Gy (63.39 μm) and 20 Gy (63.12 μm) respectively while 30 Gy treatment produced maximum stomatal density (13.85 per μm2). Furthermore, theconcentration of ABA was found to be highest (429.1 ng/gm) in morphologically dwarf (putative mutant) progenies of Nekkare. The results suggest effectiveness of induced mutation for developing dwarfing rootstocks in mango to be used in high density planting.

Impact of newly introduced liquid fertilizer as fertilizer for raising oil palm seedlings

Impact of newly introduced liquid fertilizers on growth and development on oil palm seedlings was investigated at the Nigerian Institute for Oil Palm Research Main Nursery, Benin City for two cropping seasons 2013 and 2014 respectively. The fertilizers investigated are Operon 22:0:0, Advantage 20:20:10, Boost Xtra 20:20:20 and conventional fertilizer NPKMg 12:12:17:2. The trial consists of 9 treatments laid down in Randomized Complete Blocks Design (RCBD) in three replicates at zero application (control), 28 g, and 56g per seedling respectively. Treatments were applied at 3, 5 and 8 months after planting and data were collected on seedling height, girth, number of frond production, dry matter yield and percentage of transplantable seedlings at 3, 6 and 12 months after planting. Data collected were analysed using analysis of variance (ANOVA) and their mean compared with Turkey’s Honest Significance Difference (THSD) at 5% level of probability. At 3 and 6 months after planting, seedlings treatments had no significant effects on palm height, girth and number of frond production. However, at 9 and 12 months after planting, applied treatments had significant effects on palm height, girth, dry matter yield and the number of transplantable seedlings. The highest palm height (138.5 cm), girth (23.5cm), number of frond production (12), transplantable percentage (97.7%) and dry matter yield (198.5.7 g) were obtained in seedlings that received application of 28 g NPKMg 12:12:17:2, while the least palm height (75.5 cm), number of frond production (11), transplantable percentage (68%) and dry matter yield (105.8 g) was obtained from the control. The performance of seedlings that received fertilizers were all significantly different from the control, this is an indication that the liquid fertilizers Operon 22:0:0, Advantage 20:20:10 and Boost Xtra 20:20:20 could be used as an alternate fertilizer for raising oil palm seedlings when the conventional NPKMg is not readily available.

Effect of Moisture Absorbent Hydro Polymer on Growth of Nursery Coconut Seedlings in Sri Lanka

Coconut palm is one of the most important plantation crops in the world. Selecting the best planting materials for field planting assures higher productivity. Cost of production of coconut seedling is very high in coconut nurseries, because as coir dust is becoming scarce even within the Coconut Triangle. The use of coir dust in the potting mixture might not be feasible in the near future. Therefore, it is important to test the suitability of other options available for replacing coir dust. Moisture absorbent hydro polymer (Zeba) is one of the best alternatives to be used instead of coir dust in potting media of coconut seedlings. Thus, this experiment was conducted to investigate the effect of moisture absorbent hydro polymer on growth of coconut seedlings and water retention characteristics of the growth media.
 The experiment was carried in a plant house and the laboratory at the Agronomy Division, Coconut Research Institute of Sri Lanka (CRI), Lunuwila. The treatments were laid according to Completely. Randomized Design (CRD) with twelve replicates. Different potting mixtures were used as treatments. Growth parameters of the seedlings and the moisture parameters of the growth media; moisture content and the water holding capacity were measured and analyzed.
 There was no significant difference (P>0.05) between the tested treatments in seedling girth and root volume. The results revealed that there were significant (P<0.05) differences between the treatments on seedling height, number of fully opened leaves, leaf area, dry shoot weight, dry root weight, soil moisture content and soil water retention capacity. The highest plant growth rate was recorded in T1 • There were significant (P<0.05) differences between the treatments on number of fully opened leaves at 10th and 12th weeks after planting. T1 (Top soil 4 kg+ coir dust 4 kg+ organic manure 4 kg) exhibited the highest seedling height, number of fully opened leaves, leaf area, dry shoot weight and dry root weight. Same as the T1 potting mixture, the T3 potting mixture also showed a considerable increase in plant height, number of fully opened leaves, leaf area, dry shoot weight, dry root weight of coconut seedlings. T3 exhibited the highest soil moisture content and water retention capacity. Therefore, the application of moisture absorbent hydro polymer can be used to get maximum growth and soil moisture characteristics of coconut seedlings.

Culturable bacteria diversity in stem liquid and resina from Populus euphratica and screening of plant growth-promoting bacteria

BackgroundPopulus euphratica Olivier is a kind of tree capable of growing in extremely arid desert and semi-desert environments. In this study, a culture-dependent method was used to analyze the bacterial diversity of stem liquid of P. euphratica and resina of P. euphratica, and to further evaluate plant growth promoting (PGP) activity.ResultsA total of 434 bacteria were isolated from stem fluid and resina of P. euphratica in Ebinur Lake Wetland Nature Reserve and Mulei Primitive forest. The results of taxonomic composition analysis shows that Gammaproteobacteria, Firmicutes, and Actinobacteria_c are the three dominant groups in all the communities, and the representative genera are Bacillus, Nesterenkonia and Halomonas. The diversity analysis shows that the culturable bacterial community diversity of P. euphratica in Ebinur Lake Wetland Nature Reserve is higher than that in Mulei Primitive forest, and the bacterial community diversity of P. euphratica stem fluid is higher than that of resina. According to PGP activity evaluation, 158 functional bacteria with plant growth promoting potential were screened. Among them, 61 strains havephosphorus solubilizing abilities, 80 strains have potassium solubilizing abilities, 32 strains have nitrogen fixation abilities, and 151 strains have iron ammonia salt utilization abilities. The germination rate, plant height, and dry weight of the maize seedlings treated with strains BB33-1, TC10 and RC6 are significantly higher than those of the control group.ConclusionIn this study, a large number of culturable bacteria were isolated from P. euphratica, which provides new functional bacteria sources for promoting plant growth.

THE INFLUENCE OF SHALLOT SOLUTION ON COLEUS (Plectranthus Scutellarioides (L.)) SEEDLING

Nurseries are the main critical phase in the cultivation of Coleus (Plectranthus scutellarioides (L.) R.Br.), which is useful as a raw material for traditional medicine. The key to producing well-grown, healthy, and uniform seedlings is using exogenous hormones throughout the seedling stage. Shallot has the potential to be used as an exogenous hormone. The study was conducted with shallot concentration treatment (0, 35, 70, and 100%) and soaking time (0, 12, and 24 hours). The results show shallot's activity as an exogenous hormone in coleus seedlings, including increasing the root volume of coleus seedlings through the initiation of root hairs, altering seedling height, and stimulating seedling adventitious shoot growth. Conversely, high concentrations of shallots reduced the number of coleus seedling shoots.

OsCSN1 regulates the growth of rice seedlings through the GA signaling pathway in blue light

Blue light can regulate the photomorphogenesis of plants through blue light receptors to influence seedling growth and development. The COP9 signaling complex (CSN), a vital regulator of photomorphogenesis, is a highly conserved protein complex. CSN1 is the largest and most critical subunit in the CSN with a complex N-terminal function that supports most of the functions of CSN1 and is mainly involved in plant growth and development processes. The CSN is also required in the blue light-mediated photomorphogenesis response of seedlings. In this study, the OsCSN1 subunit of Oryza sativa subsp. japonica (rice) was edited and screened, and OsCSN1 deletion mutant, OsCSN1 weak expression mutant and OsCSN1 overexpression mutant were constructed. The mechanism of OsCSN1 and its N-terminal effects on rice seedling growth and development under blue light conditions were investigated. The addition of exogenous hormone gibberellin (GA3) and gibberellin synthesis inhibitor paclobutrazol (PAC) caused aboveground phenotypic and protein (such as CUL4 and SLR1) changes. Blue light regulates the degradation of SLR1 through OsCSN1, which regulates the growth and development of rice seedling height, the first incomplete leaf, and the coleoptile. It is hypothesized that rice affects CRY-COP1 interactions after sensing blue light signals through the cryptochrome, and the nuclear localization of COP1 is regulated by the CSN complex. OsCSN1 is a negative regulator in response to blue light. The core structural domain of action that inhibits the growth of the aboveground part of rice seedlings is located at the N-terminal of OsCSN1. OsCSN1 regulates the nuclear localization of COP1 through the COP9 signaling complex and degrades SLR1 through CUL4-based E3 ligase. Ultimately, it affects the synthesis of the endogenous hormone GA, thereby inhibiting the aboveground growth and development of rice seedlings.

Radicle Emergence as Seed Vigour Test Estimates Seedling Quality of Hybrid Cucumber (Cucumis sativus L.) Cultivars in Low Temperature and Salt Stress Conditions

This work was conducted on the use of the RE (radicle emergence) test to estimate the seedling emergence (SE) and quality (seedling shoot weight (SSW), seedling root weight (SRW) and seedling height (SH)) of twelve hybrid cucumber seed lots with high germination (>95%) at low temperature conditions, high salt conditions and a combination of the two. The percentages of RE, which is a 2 mm radicle protrusion at 25 °C in the dark, were counted between 18 h and 32 h. The seeds were sown in peat moss in trays and kept at 15 °C (low temperature stress), or salty water was applied as 100 mM NaCl at 25 °C (salt stress) for three days, and both were applied in a combined-stress environment. Seedling emergence and quality parameters were reduced by both stress environments and their combination. SE, SSW, SRW and SH values ranged between: 91–100%, 614–844 mg, 102–143 mg, 6.8–8.8 cm at low temperature; 90–98%, 598–904 mg, 101–154 mg, 6.5–7.8 cm at salt stress; and 76–92%, 464–608 mg, 97–133 mg, 5.8–6.9 cm at their combination. The RE values with great differences seen among the lots (20–28 h) were regressed with seedling emergence and quality values. RE 24 h had the highest R2 and significant values in all stress environments as R2 = 0.596–0.858, p < 0.05–0.001 at low temperature; R2 = 0.620–0.827, p < 0.05–0.001 with salt; and R2 = 0.686–0.842, p < 0.05–0.001 with combined stresses. We concluded that RE as a vigour test can be used successfully to estimate the seedling quality of highly germinating hybrid cucumber seed lots. Use of the RE test in hybrid cucumber seeds and its influence on high-quality seedling production were discussed.

Effect of pH, light intensity, and fertilizers on acclimatization of endangered rooted plantlets Malus niedzwetzkyana for restoration in nature

Malus niedzwetzkyana is an endemic, endangered, and valuable plant species. To conservation Malus niedzwetzkyana in nature, it is necessary to obtain planting material with a high survival rate. Selection of optimal pH, light intensity, and fertilizers is necessary to obtain high survival rate during the adaptation period of microshoots after micropropagation and in vitro culture. For optimization of adaptation condition of in vitro rooted microshoots of M. niedzwetzkyana were used. This work investigated the effect of pH level, light intensity, and fertilizers on the growth parameters of micropropogated microshoots of M. niedzwetzkyana. To select the optimal pH and substrate four types of substrates were studied: neutral peat, acid peat, neutral soil, and acidic soil. In addition, as the artificial light source two lighting conditions were studied: LED phyto tapes (4680 lx) and fluorescent phytolamps (7410 lx). In result, highest survival rate was obtained in treatments using peat or soil at neutral pH and 7410 lx light intensity. Additionally, to acclimatize the plantlets in a greenhouse the fertilizers effects were studied: potassium nitrate, monoammonium phosphate, Special crystallon, ammonium nitrate. Thus, irrigation with the Special Crystallon was an effective treatment for seedlings and substantial growth was observed in the aboveground and underground parts of the plants post transfer to greenhouse conditions. After 4 months the average height of seedlings, the number of shoots, and the crown diameter were 114.42 cm, 25.67, and 61.83 cm, respectively with 90% survival rate of planting material after three years under natural conditions.

Influence of watering periods and organic fertilizer on seedling growth and development of two species of oak tree; Quercus aegilops and Quercus libani

Raisin drought seasons and temperature at last decades are the maximum prominent threats for the world. It is predictable that there will be several regional influences by worldwide climate alteration, especially on freshwater reserves, energy, biodiversity, agriculture, human health, forest trees and sea level. This experiment was aimed for estimate the influence of watering periods and organic fertilizers on seedling growth and development of the two oak species; Q. aegilops L. and Q. libani L.. The trial was conducted under three levels of water periods (once every 4 days, 8 days and once every12 days) and with three organic fertilizer levels (control, 25 gm, and 50 gm per pot) were used two times when seedlings age was 3 and 6 months. The result showed that the organic fertilizer with watering periods had a significant effect on seedling growth and physiological properties. The results indicated that the highest value Leaf number and seedling height increment (5.22 plant-1, and 2.20 cm, respectively) were both recorded from (4 days watering plant-1). The highest values of leaf area (10.95cm2) were recorded from the (zero or control organic fertilizer plant-1) in Q. aegilops. The highest value moistures content was (63.52 %) were recorded from interaction between (8 days of watering*25gm organic fertilizer). Therefore, it is concluded that Q. aegilops and Q. libani seedlings could success under organic fertilizer and watering periods, especially seedlings were showed best performance under well water availability. Keywords: Watering periods, Organic fertilizer, Q. aegilops, Q. libani, Morphological, and physiological pareameters &nbsp

THE EFFECT OF ROOTING MEDIA ON THE GROWTH OF MALAY APPLE (Syzygium malaccense L.) SEEDLINGS FROM STEM CUTTINGS

This study aims to determine the effect of the type of planting medium in the propagation of Malay apple cuttings. The research design used is random design non-factorial grouping that consist of 5 levels of treatment for cuttings rooting media types, i.e. soil (1), soil + compost (1:1), soil + compost + chaff charcoal (1:1:1), sand + compost + chaff charcoal (1:1:1), and compost (1) with 5 repetitions and each replication consists of 25 experimental units, and each experimental unit consists of 15 samples and 3 spare plants, so there are 450 plants. The research was conducted from February to July 2022. The parameters observed include the time of shoot emergence, sprout percentage, root length, seed height, root volume, and the percentage of life. Data analysis used ANOVA (analysis of variance) and if there was an effect, then continued with the tukey’s HSD (Honestly Significant Difference) test with a level of 5%. The results showed that rooting media mixed with soil + compost + chaff charcoal or mixed media of sand + compost + chaff charcoal could increase the percentage of survival, seedling height, root length, and root volume of malay apple seedlings from stem cuttings.