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Eucheumatoid seaweeds, encompassing the genera Kappaphycus and Eucheuma, are widely cultivated globally, particularly in tropical regions. However, ice-ice disease (IID) poses a significant challenge to their production, causing substantial economic losses. This study aimed to elucidate the factors contributing to IID in eucheumatoid seaweeds, focusing on the perspectives of seaweed farmers in Sibutu, Tawi-Tawi, Philippines. A mixed methods approach was employed, utilizing both one-to-one interviews (n = 96) and focus group discussions. The majority of the interviewed farmers were male, aged between 31 and 60 years, with extensive experience (11‒25 years) in seaweed cultivation. Notably, all participants possessed a familiarity with IID since childhood. Farmers described IID as a pathological condition affecting eucheumatoid seaweeds, characterized by the emergence of white and soft areas on the seaweed thalli. The initial stages of the disease manifest as a pale discolouration of the thalli and the presence of epiphytes or debris. Several environmental factors were identified by the farmers as contributing to IID incidence, including high or low water temperatures, low salinity (particularly after heavy rainfall), stagnant water currents, nutrient deficiencies, inadequate seedling quality, and poor farm management practices. Additionally, deepwater (nearshore) farms were reported to be more susceptible to IID. Farmers noted that easterly winds could exacerbate the disease by facilitating the infestation of epiphytes on the seaweed. Furthermore, the prevalence of IID was observed to be highest during the dry and hot season. Kappaphycus striatus was identified by the farmers as being more susceptible to IID compared with K. alvarezii and Eucheuma denticulatum. The negative impact of IID on farmers' livelihoods was also highlighted. Some mitigation strategies employed by the farmers included the application of inorganic nutrient enrichments (e.g. ammonium phosphate (16–20-0, N-P-K) and complete (14–14-14, N-P-K) fertilizers), frequent relocation of infected seaweed to different farms, and the cultivation of more IID-resistant species. Highlights: Farmers defined ice-ice disease as an anomaly in eucheumatoid seaweeds that showed white and soft thalli. Ice-ice disease is linked to unfavourable water parameters, nutrient deficiencies and poor seedling quality and management. Kappaphycus striatus is more prone to ice-ice disease than K. alvarezii and Eucheuma denticulatum. [ABSTRACT FROM AUTHOR]

Papaya (Carica papaya L.) is a widely cultivated and consumed fruit. When forming papaya seedlings, the combination of the ideal substrate to obtain quality seedlings is essential. The objective of this study was to evaluate the effect of a combination of substrates formulated with coconut fiber and doses of calcareous algae on the initial growth of papaya seedlings (Carica papaya L.). The experimental design was completely randomized in a 3 × 5 factorial arrangement, with five replications. The treatments consisted of the following substrate formulations: full coconut fiber + Gypsum; coconut fiber powder + NPK (15-10-10); coconut fiber powder + Gypsum; and doses of calcareous algae (0, 15, 30, 45 and 60 mg dm−3) applied as cover. The plant height, stem diameter, leaf area, number of leaves, shoot dry mass, root length and dry mass, and relative chlorophyll content (Chlorophyll A and Chlorophyll B) at 40 days of application of calcareous algae were evaluated. Substrates formulated with coconut fiber powder plus gypsum associated with calcareous algae doses are a great alternative in the production of papaya seedlings, stimulating plant height, stem diameter, number of leaves, and root dry mass. [ABSTRACT FROM AUTHOR]

The use of mycorrhiza and seaweed are becoming significant and complementary applications in different production systems because organisms increased quality of seedlings and crop yield. This study has been conducted under growth chamber conditions to determine some of the seedling growth parameters (length (cm), stem diameter (mm), fresh weight (g plant −1), dry weight (g plant −1), root fresh weight (g plant −1), root dry weight (g plant −1), leaf area (cm2 plant−1), SPAD, photosynthesis rate (%) and color parameters). As a plant material, Cuma F1 and Mert F1 genotype seeds were sown. Endo Roots Soluble (Mycorrhiza (ERS)) and MC-Extra (Seaweed) were applied in different doses (0, 250 and 500 mg kg−1) to seedling growing vessels at a rate of 10 ml per plant. Treatment effects in tomato were found statistically significant (p ≤.01**) on stem diameter, fresh weight, dry weight. Seedling length, leaf area and SPAD results were also statistically significant (p ≤.01**), and the results of these parameters were higher in ERS. ERS increases the leaf area and SPAD measurements in tomato seedlings. The results of pepper measurements were found to be statistically significant at p ≤.05* on root fresh weight, SPAD and photosynthesis rate. The highest values of root fresh weight, SPAD were obtained from 250 mg kg−1 doses of ERS; the highest value of photosynthesis rate was measured from 500 mg kg−1 doses of ERS on pepper. The effect of 500 mg kg−1 ERS on seedling growth was found statistically significant in pepper. [ABSTRACT FROM AUTHOR]

A field experiment was conducted at Rajasthan Agricultural Research Institute, Jaipur during two consecutive rabi seasons of 2018–19 and 2019–20 to study the effect of integrated nutrient management and seed priming on seed yield and quality in quinoa. Experiment was laid out in a split plot design with twelve treatment combinations comprising four nutrient management practices i.e. no fertilizer (NM0), N45P23K30+2% FeSO4 (NM1), N45P23K30+2% DAP (NM2); and NC125+VC1250+PSB10+KSB10+AZ10 (NM3) as main-plot treatments and three pre-sowing seed priming technologies i.e. no seed priming (SP0), 1.5% Trichoderma harziannum (SP1) and, 20% Pseudomonas fluorescence (SP2) as sub-plot treatments. Results showed that application of NM2 and SP1 exhibited significantly higher plant height (19.5 and 7.2%), number of branches (40.5 and 11.6%), seed weight (12.9 and 4.6%), total dry matter (TDM) (30.5 and 3.9%), chlorophyll content (47.4 and 3.8%) and crude protein content (27.6 and 1.8%) over control. Cumulative effect of these parameters was exhibited in terms of highest yield potential (24.64 and 23.14q ha−1) (28.5 and 9.4% higher) and excellent seed/seedling quality and energy parameters along with highest net return (₹61974 and 55501 ha−1) and B:C ratio (2.55 and 2.22) over control. A positive significant correlation for seed yield was also observed with plant height (0.983), seed weight (0.990), TDM (0.955), chlorophyll content (0.950), protein content (0.946) and seed/seedling quality parameters. Overall, application of N45P23K30+2% DAP spray at pre-flowering stage along with pre-sowing seed priming with 1.5% Trichoderma harziannum is recommended as suitable strategy to improve yield and quality in quinoa under semi-arid conditions. [ABSTRACT FROM AUTHOR]

Planting healthy seedlings with optimal growth potential is essential for proper growth and survival in forest regeneration. Assessing the seedling quality prior to planting is therefore important. In this Icelandic study, effects of root damage induced with artificial freezing in young Russian larch seedlings were examined using the root growth capacity method (RGC). Frost tolerance of roots varied during the winter, and root growth in undamaged seedlings fluctuated, indicating seasonal variations in growth rhythm. The LT50 value for root frost tolerance was −13.9°C in late January, but already at −10.6°C (LT10) root damages were severe. After one growing season, shoot elongation was significantly lower in seedlings frozen to −9°C, −13.5°C, and −15.5°C by 23%, 54%, and 72%, respectively, compared with undamaged seedlings. Control seedlings and seedlings frozen to −9°C achieved 100% survival after the first growing season. Survival in seedlings frozen to −13.5°C and −15.5°C was 85% and 27%, respectively. After the second growing season, survival decreased in all frost-damaged seedlings. The ongoing mortality demonstrates the long-lasting effects of planting seedlings with damaged root systems, and the fluctuation in root frost tolerance of young Russian larch seedlings during winter emphasises the need for care when seedlings are moved to outdoor storage. [ABSTRACT FROM AUTHOR]

Cultivating a high quality rapeseed blanket seedling is crucial if the mechanized transplant of rapeseed is to become an effective part of oilseed production in China. Nitrogen (N) strongly affects the growth and quality of the rapeseed seedling. This study investigated the agronomic traits, physiological indexes, the surviving number of blanket seedlings, and the survival rate after transplanting two canola (Brassica napus L.) cultivars (Ningza 1838 and Yangyou 9) treated with five N rates (0, 0.5, 1.0, 1.5 and 2.0 g N per tray). Plant height, leaf age, leaf area, collar length, fresh and dry weights, moisture content, and N concentration in root and shoot all increased as the N rate increased. The survival number, collar diameter, root to shoot ratio at the 30th day after sowing and the survival rate at the 10th day after transplanting increased at first then decreased as N rate consecutively increased. The survival number and survival rate under the 1.0 and 1.5 g N per tray treatments were most improved amongst N treatments, although there was no significant difference between these two N treatments. This suggests that to achieve high-quality blanket seedling needed for mechanized transplanting, the application of N at rates of 1.0 to 1.5 g N per tray at the one-leaf and one-heart stages is recommended. [ABSTRACT FROM AUTHOR]

The soil based potting mix (media) of four altered proportion of farmyard manure (FYM) and three different pot volumes were considered for quality seedlings production of tomato and chili in cylindrical shaped paper pots made of bio-degradable newspaper material (density 50 g m−2). The experimental factors include three paper pot sizes of 50 cm3 (V1), 70 cm3 (V2), and 90 cm3 (V3) volume and four potting mixes made of 90% (M1), 70% (M2), 50% (M3) and 30% (M4) of different FYM proportions with equal proportions of sand and top layered soil were used in the experimentation to study the seedlings growth characteristics at the stage of transplanting. Though several seedlings growth characteristics are involved to recognize the good seedling, but the experimental selection criteria was based on two most dominating characters, that is, height and dry weight of seedlings. After completion of the experiment, the data was statistically analyzed to for rectify combination of potting media mix with respect to pot volume for the large-scale production of seedlings. It was found that pot volume of 90 cm3 (V3) filled with M4 mix (includes 30% FYM, and rest of each 35% sand and top soil) were the best for growing vegetable seedlings. [ABSTRACT FROM AUTHOR]

In the cassava (Manihot esculenta Crantz) cultivation system, planting seedlings directly in the field is widely used. However, establishment of plants by this method is slow, taking about 15 days to start the formation of shoots and roots. The plant in this phase is not very competitive, which leads to the formation of uneven and low-productivity areas. Production of seedlings on substrates is an alternative that can improve the uniformity of the plant stand, as well as allow more careful selection of the best propagules. Viability of this propagation method depends on the substrate, which must have ideal physical and chemical properties to meet the needs of the crop. The objective of this work was to evaluate the use of decomposed buriti stem (Mauritia flexuosa L. f) as a substrate in the propagation of cassava seedlings. The substrates were composed of decomposed buriti stems and soil in the following proportions: 0:100; 20:80; 40:60; 60:40; 80:20; and 100:0 (volume). The addition of decomposed buriti stem improved development of the aerial part, provided greater survival for cassava seedlings in an increasing linear fashion, and promoted increases in the levels of N, P, K, Ca, and Mg of cassava seedlings. It was determined that there is agronomic efficiency in the use of buriti residue for the production of cassava seedlings. [ABSTRACT FROM AUTHOR]

Establishing the optimal time for rooting permanence and evaluation of the rooting quality of eucalypt clones allows us to optimise the production process and increase the quality of the seedlings produced. This study aimed to determine the optimal time for rooting permanence and the rooting quality of three eucalypt clones. Minicuttings from the clones AEC 0144, GG100 and VM01 were propagated in a greenhouse and evaluated for six weeks. The percentages of callus- rooted, rooted and live minicuttings, the number of roots, root system length, and root dry mass were evaluated. The selected clones differed in the speed and rate of rooting, reflecting differences in the optimal time in the rooting house for the minicuttings. Clone VM01 presented the lowest rate and speed of rooting. We conclude that optimisation of the rooting process can be achieved using logistic model fitting and noting the intercept between the daily current increment and daily average increment curves of the rooting percentage, since the other variables are dependendent on this. [ABSTRACT FROM AUTHOR]

To what extent does the availability of nutrients to the mother plant affect seed quality and consequently seedling establishment? Based on this question, we evaluated the early plant establishment of the super-early BRS FC104 common bean. For that, we used seeds produced by mother plants in mutualism with nitrogen-fixing bacteria (Rhizobium leucaenae, strains SEMIA 4077, SEMIA 4080 and SEMIA 4088, at a ratio of 1:1:1) and/or fertilized with different nitrogen doses. These were applied in the physiological stages of higher nutrient demand. The cultivation system used was no-tillage. Our findings demonstrate that plants in mutualism and fertilized with 150 kg ha−1 of N-fertilizer in V0 show increments in the seedling's establishment ability (78, 33%). However, with this dose the percentage of vigorous normal seedlings decreases (42.0%). Mineral fertilization can be applied at any stage of the common bean development (64.27%). Mineral nitrogen causes a fixed variability in the system, regardless of the dose. [ABSTRACT FROM AUTHOR]

The segmentation of digital images in red, green and blue (RGB) components is a low-cost method for monitoring leaf chlorophyll concentrations and seedling quality. The two congeneric species, Cariniana legalis and C. estrellensis, are distinguished based on differences in bark texture and the colour of their new leaves. We compared indices based on leaf colour segmentation in RGB to predict total chlorophyll concentrations (Chlt) in the leaves of seedlings of these two species. Mature leaves were digitalised in a flatbed scanner and segmented in red (R), green (G) and blue (B). The relationships between the three RGB indices and Chlt were tested. Additionally, we calculated the anthocyanin content-chroma basic (ACcb). The mean value of ACcb was significantly higher in C. legalis than in C. estrellensis, demonstrating a higher anthocyanin concentration in C. legalis leaves. Based on the highest coefficients of determination (R2) and lowest prediction errors (PE), for all indices, the best results were obtained for C. estrellensis. The presence of anthocyanins in the leaves of C. legalis and the limitation of the RGB colour segmentation indices for separating all leaf pigments might be the main causes of the differences in Chlt prediction in the leaves of these two congeneric tree species. [ABSTRACT FROM AUTHOR]

In vegetable production, seedling propagation is one of the most important steps as it directly influences the final performance of the plants. In order for such condition, the propagation substrate must be in good condition. The objective of this work was to evaluate the effect of different combinations of tannery sludge and urban waste compost as substrates in comparison to the commercial substrate Maxfértil® on the growth and quality of eggplant seedlings. The experiment was conducted in a greenhouse using a randomized block design with eight treatments and six replications. The commercial substrate was Maxfértil®, a crushed pine bark, with limestone, and seven treatments with increasing proportions of tannery sludge/decreasing urban waste compost (0/100; 10/90; 30/70; 50/50; 70/30; 90/10 and 100/0 v/v). Characteristics of emergence, growth, quality and leaf nitrogen (N) content were evaluated. No difference was found in the emergence of eggplant seedlings among the different treatments used; however, the growth characteristics, quality and N content featured significant effects when the seeds were propagated in alternative substrates. Regression adjustments pointed to an optimal range of 41–49% of tannery sludge associated with urban waste compost for the evaluated characteristics. The strong correlation between SPAD and N content shows its potentiality in detecting N deficiencies in seedlings. The use of tannery sludge residues associated with urban waste compost seems to be an appropriate and sustainable practice for recycling with high agronomic potential. [ABSTRACT FROM AUTHOR]

Identification of stocktype attributes that speed up field establishment has potential to reduce rotation time of Christmas tree productions. Such morphological and physiological attributes can be targeted in the nursery production. This study tested the effects of container type and nursery seedling density on stocktype attributes at planting and the effects of these on field performance over two years in Abies lasiocarpa and A. nordmanniana Christmas tree stock. Nursery conditions had a considerable impact on seedling attributes at planting. Although sets of these correlated stocktype attributes contributed to forecast field performance, the predictive power was low. No simple relationships were found between plant biomass, stem diameter or height at planting and biomass at final harvest in either of the two species under the range of stocktype variation and field conditions tested. Contrary, stem diameter and stem height at planting explained some of the responses in stem diameter and height after two years in the field. Thus, any target seedling approach would have to be based on a combined set of stocktype attributes exploring more productive stocktypes. The differences observed between stocktypes were largely due to size differences and ontogenetic drift, and stocktypes converged towards a similar field phenotype over time. [ABSTRACT FROM AUTHOR]

The substrate is essential to ensure suitable conditions for the growth of Passiflora setacea seedlings. Thus, a study was conducted to investigate the effect of alternative substrates formulated with bee nest and termite mound materials on the growth of P. setacea cv. BRS Pérola do Cerrado seedlings. Six substrate combinations formulated from different proportions (v:v) of bee nest material (BNM) and termite mound material (TMM) or commercial substrate were tested considering the randomized block design with four replicates. The following substrates were used: S1 = BNM100%; S2 = BNM75% + TMM25%; S3 = BNM50% + TMM50%; S4 = BNM25% + TMM75%; S5 = TMM100%; and S6 = commercial substrate (Click Mudas®). The plant height, stem diameter, root length, root dry matter (RDM), shoot dry matter (SDM), total dry matter (TDM), and morphological indices were measured. Passiflora setacea seedlings have better development with the use of substrates S1, S2, and S3, with greater emphasis on the substrate S1. The substrate S1 (100% BNM) should be recommended for the production of P. setacea cv. BRS Pérola do Cerrado seedlings, for improving plant development and providing higher quality seedlings. [ABSTRACT FROM AUTHOR]

Survival rate of seedlings planted in arid and semi-arid land parts of Turkey is low. New methods and techniques are needed to increase survival rate and growth performance of seedlings used in afforestation practices in the region. The aim of this study is to evaluate the growth performance of Taurus cedar (Cedrus libani A. Rich) seedlings receiving different mycorrhizae inoculation treatments. The experiment was conducted in the western part of Central Anatolia. Two commercial mycorrhizal cocktails were used for treatments in a completely randomized design experiment. Both ecto- and arbuscular mycorrhizal fungi were observed in the same root system of the seedlings after the mycorrhizal inoculation. But the relationship between ecto- and arbuscular mycorrhiza was antagonistic. Analysis of the data indicated that mycorrhizal colonization was effective on seedlings' morphological characteristics. The significant differences were detected for root collar diameter, shoot height, root length, specific needle area, shoot dry weight, root dry weight, shoot fresh weight, root fresh weight, shoot to root dry weight ratio, and Dickson quality index of seedling received different treatments. Mycorrhizae positively affected plant nutrition by increasing uptake of nutrients. [ABSTRACT FROM AUTHOR]

In Nordic climates, the weather allows a narrow time window during spring and summer for forest seedlings to be transplanted from indoor growth to outdoor conditions. If a new method for year-round cultivation under LED lamps is to be successfully introduced in forest nurseries, a cold storage phase for batches produced outside of the vegetation period needs to be included in the concept. Different short-day treatments for induction of cold hardiness in very young seedlings of Picea abies and Pinus sylvestris cultivated solely under LED lamps were investigated. The study compared a combination of two photoperiods (5 h or 8 h) at three different temperatures (5°C, 10°C or 20°C) applied during five weeks. Chlorophyll fluorescence, shoot electrolyte leakage and molecular testing for gene expression of cold acclimation were used to assess the treatments. After a period of three months in cold storage at 2°C, the vitality of the seedlings was evaluated using a root growth capacity test. Lower temperatures during the treatments, especially for Pinus sylvestris, had a significant effect on inducing cold hardiness. The results showed that the photoperiod should not be overly reduced to allow photosynthesis and generation of carbohydrate reserves but it could be optimized to reduce electricity consumption. [ABSTRACT FROM AUTHOR]

Trembling aspen is an important component of the boreal mixedwood forest region and is a key component of numerous ecological functions. As a result, aspen has become a target species for forest restoration after industrial disturbance; however, aspen seedling afforestation research is still in its infancy as seedling and site characteristics and their interactions which drive establishment success in the field are poorly understood. This study examined the growth response of three aspen size classes across six sites differing in competition and soil moisture availability. With competing vegetation present, tall seedlings with lower root-to-shoot ratios had less height growth aboveground and reduced root egress (relative to total root mass) belowground, indicating that light was not the most limiting factor aboveground and that higher root-to-shoot ratios may aid in competition for rooting space. Differences between size classes were less pronounced on sites with no competition or sites with extreme conditions (high competition or low soil moisture availability) during outplanting. Reducing competing vegetation before outplanting improved height growth, particularly in seedlings with high root-to-shoot ratios. For aspen, planting short to medium-sized seedlings with higher root-to-shoot ratios offers a reasonable balance between cost and production of a stress-tolerant seedling. [ABSTRACT FROM AUTHOR]

Climate change has a negative impact on crop production by inducing several stresses throughout plant growth. As the germination is one of the critical stages, this study was to assess the impact of elevated carbon dioxide (eCO2) and associated temperature stress on germination of rice. The study was conducted using the rice genotype CO 51 in artificially induced eCO2 condition using open-top chamber (OTC). The efficiency of seed priming treatment with salicylic acid (SA), citric acid (CA), ascorbic acid (AsA) and distilled water (hydropriming) to alleviate stress due to eCO2 and temperature were also studied. SA 25 mg l−1 and AsA 100 mg l−1 enhanced germination, other seed quality parameters along with α- amylase activity. Also, the activity of antioxidant enzymes like catalase, peroxidase and superoxide dismutase was increased. These parameters positively affected the germination and growth by mitigating the effect of oxidative stress induced under eCO2 conditions. So, SA, CA and AsA can be effectively used for maintaining seed quality parameters and seedling growth during the stresses. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the biological rhythm of the vegetative growth and nutrient content of the yellow passion fruit seedlings produced in substrates with different levels of based on the decomposed stem and babassu (DBS): S1 – 20%, S2 – 40%, S3 – 60%, S4 – 80%, S5 – 100% DBS and S6: commercial. Were investigated the plant height (PH), stem diameter (SD), emergency speed index (ESI), germination (%G), leaves number (NL), root length (RL), root volume (RV), dry mass of the shoot (SDM), dry mass of the root system (DMRS), Dickson quality index (DQI) periodically for 60 days. The accumulated nutrient (N, P, K, Ca, Mg and B) contents were determined after this period. The data were submitted to ANOVA, significant means were compared by the Tukey test (P <.01). ANOVA results showed a significant effect (P <.01) for using DBS in 80% (S4 and S5) on RV, DQI, and DMRS in relation to the commercial one. In addition, there was greater accumulation (P <.01) of N, P, K and B in contents S4 and S5. Therefore, the use of the babassu decomposing stem as a substrate positively influences the vegetative growth rate of yellow passion fruit seedlings, especially due to its nutritional aspect, promoting a greater accumulation of nutrients, mainly boron. Mixing with the soil in the ratio 80/20, respectively, promotes the best biometric and nutritional responses, with the best quality conditions for seedling formation. [ABSTRACT FROM AUTHOR]

Autumn sown small seedlings for later transplanting into large containers have been introduced in Swedish forest tree nurseries. Containerized transplants of Norway spruce (Picea abies (L.) Karst.) from three Swedish nurseries were frozen stored during the autumn of 2014 to find out storability and post-storage vitality. Seedling storability was determined by measuring electrolyte leakage after freezing shoots to −25°C (SELdiff−25), by measurements of dry matter content (DMC) of seedling shoots and by the commercial molecular test ColdNSure™. Vitality of seedlings after storage was determined by measuring the leakage of electrolytes from shoots (SEL), and seedlings were also tested in regrowth tests. All three methods for storability assessment gave similar predictions, except in one case where DMC showed "not storable" for successfully stored seedlings. Our results indicated that young transplants can be successfully short term stored before reaching the target levels for safe long-term storage of conventional seedlings. Early storage of young transplants resulted in low post-storage survival and vitality expressed as root growth capacity and shoot electrolyte leakage (SEL). A prolonged duration in storage generally resulted in lower survival as well as lower root growth capacity and higher levels of SEL, especially for seedlings stored at earlier dates. [ABSTRACT FROM AUTHOR]

Quality of vegetable seedlings is affected by nursery management practices, essentially growing media. For sustainable greenhouse horticulture, it is important to characterize biologically based approaches to improve plantlet quality. Here, we investigate the possibility of developing a biotized growth substrate for nursery production using date palm wastes (DPWs) peat as an alternative to commercial sphagnum peat and indigenous arbuscular mycorrhizal fungi (AMF). A greenhouse experiment was established using different rates of DPWs peat to substitute commercial peat in both conventional and organic nursery production systems. Lettuce seedlings were inoculated or not with native AMF isolated from plots with conventional or organic production system (CM and OM respectively). When lettuce plantlets attained commercial size, a microscopic observation revealed that the establishment of mycorrhizal association was successful in all mixtures of growing media. Significant increase in growth parameters (height shoot, number and area of leaves, shoot and root biomass) were observed on plantlets inoculated with indigenous AMF isolated from organic plot compared to those isolated from conventional plot and to control (without AMF). Commercial peat partial substitution with DPWs peat in proportion of 25–50% improves better lettuce performance than complete-peat use. Consequently, these mixtures seem to be an appropriate formulation for sustainable nursery production. [ABSTRACT FROM AUTHOR]

In this study, effects of foliar application (with constant 0.2% concentration) of chemical NPK (N20:P10:K20) and organic fertilizers of Biomin (an organic aminochelate fertilizer), Humifolin (a humic acid based fertilizer), Biomin + Humifolin, a synthetic macro-micro mixture, soil application of NPK (600 mg.kg−1 of the N20:P10:K20 formulation), and a no fertilizer control were evaluated on growth and quality of chili pepper (Capsicum annuum var annuum) seedlings under greenhouse conditions with cool temperature of 15 ± 3 °C. The results showed that most growth and quality traits were best improved by foliar application of Biomin aminochelate followed by Humifolin fertilizer. Higher values for leaf area, leaf number, chlorophyl index, root and shoot biomass, and leaf concentration of soluble sugars, N, K, Ca, and Zn, were attributed to foliar application of Biomin and Humifolin. The mixture of Biomin + Humifolin had reduced values of those parameters indicating possible negative interaction when these two organic fertilizers are mixed. [ABSTRACT FROM AUTHOR]

Despite the importance of starch for tree growth, methodological challenges in starch analysis slow down the research on its ecological importance. In this study, a rapid monitoring method was developed for measuring starch content in Pinus taeda L. seedlings after cold treatments. A linear mixed-effects model was used to analyze the effects of cold treatments, seedling tissue types and their interaction on starch content. Mid-infrared (MIR) and near-infrared (NIR) spectra were surveyed, and the results were analyzed using partial least squares regression to determine the starch content. The determination coefficient for calibration and residual predictive deviation were compared between MIR and NIR models to assess the variability of the established models. The results showed that the effects of cold treatments, seedling tissue types and their interaction on starch content were significant. Compared to MIR spectra, NIR spectra is more suitable to estimate starch content in the seedlings. Using NIR spectra, roots provided the most accurate estimates of starch content. The presented guidelines regarding data accuracy as a function of MIR/NIR spectra of samples represent an important methodological reference for starch quantification, which will improve the understanding of the fundamental role of starch in seedlings against environmental forces. [ABSTRACT FROM AUTHOR]

This study reports on the influence of seed position within the fruit and shoot development on the production of jackfruit in vitro. Seeds were extracted from the different sections in the fruit and shoot tips excised from the resultant seedlings. The tips were cultured in vitro on media supplemented with 6-benzylaminopurine (BAP) or thidiazuron (TDZ). The seeds from the middle and basal sections of the fruit were larger and produced larger seedlings than those from the top. Seeds from the basal position took 10 days to germinate and produced seedlings 11 cm tall with four or five leaves. Partially covered and fully open shoots from 6-8 week-old seedlings performed best. The highest frequency of shoot induction (100%) and multiple shoot production (7.31 ± 1.2) with a mean length of 3.6 ± 0.13 cm was observed on Murashige and Skoog (MS) media supplemented with 3.0 mg/L BAP. Driver and Kuniyuki (DKW), and MS media were equally effective in shoot multiplication. More than 80% of the rooted plants survived culture, indicating that this technology could be used to conserve wild germplasm. [ABSTRACT FROM AUTHOR]

This experiment aimed to compare combinations of sewage sludge-based substrates on the growth of Acacia mangium seedlings by principal component analysis (PCA) and orthogonal contrasts (OC). It was conducted in structures of a forest nursery, localized in Southeast of Brazil, in 280 cm3 tubes constituted by 14 treatments and 5 replicates of four plants. When the seedlings reached 100 days after sowing, the treatments containing sewage sludge associated with vermiculite were those that stood out for the growth of A. mangium seedlings, showing the highest averages for the biometric features. The addition of coconut fiber and coffee straw did not produce good growth as well as the evaluated commercial substrate. It can be stated that the use of principal components and OC were efficient in evaluating the best substrate added to the sewage sludge having a limitation in identifying the best ratio between constituents of the substrate. [ABSTRACT FROM AUTHOR]

Establishing vegetables in the field using mechanical transplanters with only plant metering devices requires transplants with heavy soil blocks around the roots. An investigation was conducted to study the effects of amount of vermicompost in a soil-based potting mix and initial compaction of the mix on growth of seedlings and soil block strength for mechanical transplanting. Seedlings of Tomato (Solanum lycopersicumL.), Eggplant (S. melongenaL.), and Chili pepper (Capsicum frutenscensL.) were produced in two seasons in plastic plug trays with a potting medium in which vermicompost made up 20%–50% by volume in 60 and 100 cc tray cells. Potting mix with 20% vermicompost by volume in soil in 100 cc cells produced good growth of tomato and chili pepper transplants in season 1. Potting mix containing 20%–30% and 20%–40% vermicompost in soil in 100 cc cells produced good growth of tomato and chili pepper transplants, respectively, in season 2. Potting mix with 30%–40% and 30% vermicompost by volume in soil in 100 cc cells produced good growth of eggplant seedlings in seasons 1 and 2, respectively. The effects of initial compaction of potting mix on water requirement, plant height, and soil block strength was studied for the production of tomato seedlings. Potting mix with 30% vermicompost in 100 cc tray cells and initially compacted to the dry density of 0.88–0.90 g·cm−3was most suitable for production of seedlings of sufficient height and soil block strength for mechanical transplanting. [ABSTRACT FROM AUTHOR]

This research was conducted to investigate the effects of different medium compositions on physicochemical properties and the growth of two tomato varieties. Five treatments were applied, combining medium composition with rice husk ash (RHS) and coconut fiber (CF) with the following proportions: 1/3 Peat moss + 1/3 rice husk ash + 1/3 coconut fiber (T1); 1/3 Vermicompost + 1/3 rice husk ash + 1/3 coconut fiber (T2); 1/3 Cattle manure compost + 1/3 rice husk ash + 1/3 coconut fiber (T3); 1/3 Chicken manure compost + 1/3 rice husk ash + 1/3 coconut fiber (T4); 1/3 Hog manure compost + 1/3 rice husk ash + 1/3 coconut fiber (T5). The results demonstrated that between pH, electrical conductivity (EC) value, and nutrient content in the media, there was a significant difference that led to different concentrations of total macro- and micronutrients in the shoots of both varieties. In addition, the root weight, shoot weight, and root volume were affected by medium composition for two varieties in seedling stage. A mixture of cattle manures composted with RHS and CF under the rate (1:1:1 by volume), respectively, gave the highest value of germination rate, plant height, leaf number, and plant biomass. Medium composition significantly influenced the germination rate and elongation of seedlings, specifically for each tomato variety. Therefore, cattle manure compost as a medium supplement improves seedling quality and growth of the two tomato varieties. [ABSTRACT FROM AUTHOR]

The identification of alternative substrates suitable for seedling production is very important, while boron nutrition is also relevant due to plant requirement and its difficult management. Thus, four experiments were carried out from October 2012 to April 2013 to evaluate the effect of substrates using decomposed buriti (Mauritia viniferaMart.) stem (DBS) and boron fertilizing for seedling production of yellow passion fruit (Passiflora edulisSims). The experimental design was completely randomized in factorial scheme 6 × 2 + 1, referring to the substrates [S1: DBS, S2: soil and sand 1:1 (20%) + DBS (80%), S3: soil and sand 1:1 (40%) + DBS (60%), S4: soil and sand 1:1 (60%) + DBS (40%), S5: soil and sand 1:1 (80%) + DBS (20%), S6: commercial substrate (additional treatment) and S7: soil, sand and manure 1:1:2] with and without boron. The seedling emergence, emergence rate, plant height, stem diameter, root length, root volume and dry mass of roots and shoots were recorded. The substrates S2 (without B fertilizing) and S4 (B fertilized with 0.5 mg dm−3) produced seedlings with more than 3.0 g of shoot dry mass and at least 30 cm in height, and can be used for production of high-quality yellow passion fruit seedlings. [ABSTRACT FROM PUBLISHER]

This study evaluated nutrient accumulation of yellow passion fruit seedlings produced in substrates containing proportions of decomposed buriti (Mauritia vinifera Mart.) stem (DBS) and the boron in this process. Four experiments were conducted in Federal University of Piauí in Brazil. The experimental design was completely randomized in factorial scheme 6 × 2 + 1, referring to the substrates [DBS (100%), soil and sand 1:1 (20%) + DBS (80%), soil and sand 1:1 (40%) + DBS (60%), soil and sand 1:1 (60%) + DBS (40%), soil and sand 1:1 (80%) + DBS (20%), commercial substrate (additional treatment without boron) and soil, sand and manure 1:1:2] with (0.5 mg B.dm−3) and without boron. The following variables were recorded: total nitrogen, total phosphorus, potassium, calcium and magnesium, boron, absorption efficiency index and chlorophyll. No influence concerning the substrate composition was noticed on nutritional status, but boron influenced on K and Mg of yellow passion fruit seedlings. [ABSTRACT FROM AUTHOR]

This study was designed to understand the effects of different soil organic amendments on germination and seedling vigour of Okra (Abelmoschus esculentus L.). Five treatments with organic amendments (farmyard manure, vermicompost and biochar) and mineral fertilizers were designed in randomized block design with three replications. Results showed that organic amendments significantly enhanced per cent seed germination and emergence speed index compared to inorganic fertilizer. Highest homogeneity of seed germination (CVgt = 20.74) was observed in vermicompost. Plant height, root length and leaf area were higher in vermicompost and biochar than farmyard manure. Both allocation of biomass to above ground parts and Dickson quality index were highest in seedlings from the plots amended with vermicompost. The study revealed that compared to biochar, vermicompost and farmyard manure significantly enhanced the germination and growth of Okra seedling, but the stimulation was best in vermicompost-amended plots. [ABSTRACT FROM AUTHOR]

Zeolite has been successfully used in growing media for containerized production systems. In this study the effects of zeolite utilization with the mixture of different growing media (GM) on the seedling quality and nutrient contents of cucumber (Cucumis sativusL. cv. Mostar F1) were determined under the greenhouse conditions. For this purpose, natural zeolite, perlite, turf, and their different mixture forms were used as GM for growing of cucumber seedlings. Effects of these substances on the seed germination, plant height, stem diameter, seedling fresh weight, and macronutrient [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg)] and micronutrient [iron (Fe), zinc (Zn), manganese (Mn), and copper (Cu)] contents were studied. As a result of this study, the effects of GM on the seedling quality parameters were found to be significant for seed germination, plant height, stem diameter and fresh weight, and nutrient contents of seedlings. The best results were generally obtained from turf + zeolite mixtures. [ABSTRACT FROM AUTHOR]

The effects of clinker dust and wood ash on Norway spruce and Scots pine seedlings were compared in buried pots. Clinker dust (0.5 kg m−2) and wood ash (0.5 kg m−2) were applied to the surface of a nutrient-poor mineral soil. In the second year, the increase in soil pH by the dust and ash were larger than in the first year. Both alkaline treatments caused a large increase in the needle potassium (K) concentration. An excess of soil K relative to magnesium (Mg) was observed by decreased Mg concentration in needles shortly after treatment. However, Mg concentration in needles stayed in the sufficiency range. Current results confirmed earlier findings that despite a positive effect on base cation nutrition, wood ash has a low potential for increasing the biomass of forest stands on mineral soils due to the N limitation in these soils. [ABSTRACT FROM PUBLISHER]

Seed system reliability is of major importance in farming. Whereas earlier studies analysed mainly annuals, this study focuses on a perennial. Oil palm in Benin was chosen as a case study because farmers complained about non-hybrids (duraandpisifera) in plots allegedly planted with 100% hybrid (tenera). This study assessed the reliability of the oil palm seedling supply system over past decades and its main drivers. An event ecology approach was used to identify causal mechanisms accounting for the observed variation in oil palm types on smallholder plots. A total of 378 plots belonging to 248 farmers that were allegedly planted withtenerabetween 1969 and 2009 were sampled, and shell thickness of fruits was assessed to determine whether palms weretenera,pisifera,ordura. The proportion ofteneravaried with seedling supply source, farmers' geographic position, seedling purchase price, and year of planting. The proportion ofteneradecreased with year of planting. Socio-institutional mechanisms associated with the observed variation in smallholder plots were national policy change, local arrangements for seedling supply to smallholder farmers, and farmers' personal characteristics. The implications of the observed decrease in the reliability of the seedling supply system are discussed. [ABSTRACT FROM AUTHOR]

Seedling vigor is the basic component of the transplanted rice, which depends on its growing environment and proper age. Thus the influence of nursery management and seedling age was evaluated after transplanting 10, 20, 30, and 40-days older seedlings raised by using seed rate (high and low) and nitrogen (N) (with and without) in rice growing season 2008 and 2009. Study revealed that 10-days older nursery seedlings, irrespective to nursery-bed treatments, showed accelerated growth start after transplanting in main field while at later stages significant interaction was observed. Transplanting of 20-days older fertilized seedlings grown at low seeding density at nursery-bed resulted in similar growth performance as in younger. Maximum net-benefit (45111, 44402 Rs. ha−1) was recorded with transplanting 10-days older nursery seedlings while the fertilized seedlings grown at lower seeding density recorded highest net-benefit (37908, 36780 Rs. ha−1) in both the years. [ABSTRACT FROM PUBLISHER]

Growing conditions during transplant production influence seedling quality and performance, transplant establishment, and subsequent yield. The effects of spectra combinations of blue, red, and white light, generated by monochromic light-emitting diodes (LEDs), on physiological and morphological characteristics of tomato (Solanum lycopersicumL.), cv. Kingston, and pepper (Capsicum annuumL.), cv. California Wonder, seedlings were investigated. Tomato and pepper transplants treated with monochromic red, or combinations of red with blue light, produced greater stem diameter, whereas blue light alone, or in combination with red, reduced transplant height. In tomato the most lateral branches were produced on seedlings under blue light, but pepper transplants were not affected. The most leaf area in tomato and pepper transplants was obtained under monochromatic blue or red light, respectively. Proline, an important compound related to plant stress tolerance, was produced at the highest level under blue light in both plants. For tomato, red light alone or in combination with blue or white light reduced the number of leaves required before the first cluster. This occurred in pepper transplants when higher ratios of red light (up to 100%) were applied. For both plants rates of first cluster formation and first yield were higher when combinations of blue and red lights (regardless of their ratio) were used. The most vitamin C was in fruit produced on plants developed from transplants grown under blue light. Fruit total soluble solids were also higher in tomato plants developed from blue light–treated tomato seedlings. There appear to be beneficial effects due to exposure of plants during seedling development to light spectra that extends beyond transplanting. The effects of light spectra appear to be genus or species specific. The LED technology did not differ from other technologies and has merit for production of some vegetable seedlings. [ABSTRACT FROM AUTHOR]

Growth room studies were conducted to determine the impact of Brassicaceae seed meals on the emergence of tomato and pepper seedlings in Pythium ultimum infested soils. Pasteurised Burch sandy loam soils were amended with intact and denatured seed meal of rape seed and mustard. Brassica juncea or Brassica napus intact seed meal increased the tomato and pepper seedling emergence. Interestingly, B. napus amended soils resulted in the same seedling emergence with B. juncea regardless of their relatively lower glucosinolate content compared to mustard-based seed meals. Seedling emergence in soils amended with intact Sinapis alba seed meal was significantly the lowest for both tomato and pepper seedlings. In contrast, seedling emergence was higher in soils amended with denatured than intact S. alba seed meals suggesting some glucosinolate-related inhibitory effect on seedling emergence of both crops. Glycine max seed meal amendment improved the seedling emergence better than the control but to a lower-level when compared to glucosinolate containing seed meals. This finding suggests that even though improvement of seedling emergence of tomato and pepper in P. ultimum infested soils can be achieved using Brassicaceae seed meals, it cannot be entirely attributed to glucosinolate-related processes. These studies demonstrate that intact B. napus and B. juncea seed meals can be used to improve tomato and pepper seedling emergence in P. ultimum infested soils. [ABSTRACT FROM PUBLISHER]

Seedling morphological quality standards are lacking for bottomland hardwood restoration plantings in the Lower Mississippi River Alluvial Valley, USA, which may contribute toward variable restoration success. We measured initial seedling morphology (shoot height, root collar diameter, number of first order lateral roots, fresh mass, and root volume), second year field heights and diameters, survival, browse, and top dieback of five species – cherrybark oak (Quercus pagoda Raf.), green ash (Fraxinus pennsylvanica Marsh.), Nuttall oak (Q. nuttallii Palmer), sweet pecan (Carya illinoensis (Wangenh.) K. Koch), and water oak (Q. nigra L.). Seedlings were obtained from three regional nurseries (Arkansas, Louisiana, and Mississippi), planted on three sites (Arkansas, Louisiana, and Mississippi), and treated with or without chemical weed control. Site×nursery interaction and weed control (without interactions) usually affected survival, whereas site×weed control interaction and nursery (without interactions) influenced second year heights and diameters. Weed control generally increased survival rates, as well as second year height and diameter. Effects of initial morphological characteristics on field survival and height and diameter growth were generally dependent on the other morphological parameters. Target morphological characteristics were identified as 99, 84, and 82 in height/diameter ratios (equal units) for cherrybark oak, green ash, and Nuttall oak, respectively; mean initial height of 40–43 cm in sweet pecan; and mean initial fresh mass/root volume of 2.7 g ml−1 in water oak. Seedlings with means above these values may be more susceptible to dieback or mortality after outplanting, likely associated with excessive shoot relative to root biomass. [ABSTRACT FROM AUTHOR]

The use of the mini-plug system for the production of container seedlings is relatively new, so there is little information on the potential impact of method on the quality of planting stock. The objective in this study was to evaluate the impact of mini-plug growing method on quality of Pinus brutia seedlings, and compare the performance of this stock type with that of standard container nursery stock. Seedling survival, growth and physiological status (root growth potential, shoot electrolyte leakage) were measured after pre-cultivation in mini-plugs, at the end of the first growing season in standard containers and after field transplanting. Our results showed that mini-plug transplants of P. brutia seedlings performed as well as the standard planting stock currently used in nursery operation in Greece. For the pre-cultivation of P. brutia seedlings in mini-plugs, the use of peat and a density of 2000 mini-plugs m-2 are recommended. [ABSTRACT FROM AUTHOR]

A pot trial was implemented to determine the effect of soil water stress following transplanting on shoot water potential and stomatal conductance of Pinus patula seedlings. The relationship of seedling morphology to measures of water stress was also investigated. The trial consisted of two watering treatments: a control (no water stress) and a severe water stress (no further water after planting). The treatments were applied to recently transplanted seedlings selected to reflect a range of sizes typical in an operational environment. Measures of shoot water potential and stomatal conductance, root and shoot growth and environmental variables were made. The results indicated that P. patula seedlings tolerated high air and soil temperatures (above 35°C) and low soil water availability (-1.5 MPa). The water potential threshold for changes in stomatal conductance was in the region of -0.8 to -0.9 MPa and stomatal closure had occurred at a shoot water potential of between -1.8 and -2.1 MPa. Mortality occurred when shoot water potential declined to below -3.0 MPa. There was variability between seedlings in their potential for survival and growth. Inherently bigger seedlings had a greater capacity for new root growth following planting. Mass of new roots was significantly and positively related to higher rates of transpiration under conditions of low soil moisture. [ABSTRACT FROM AUTHOR]

The aim of this study was to measure a number of morphological and physiological parameters of planting stock material of forest species grown in mini-plugs and to evaluate them as indicators of planting stock quality under different density and substrate treatments. The studied species were black locust (Robinia pseudoacacia L.), Italian cypress (Cupressus sempervirens L.), brutia (Pinus brutia Ten.) and black pine (Pinus nigra Arnold). Seeds were sown in two growing substrates (peat and stabilized medium), using two mini-plug densities (3500 and 975 mini-plugs m-2). After a 4-5 week growth period under controlled conditions, both morphological (root length, shoot height, leaf area, root and shoot dry weight) and physiological (shoot electrolyte leakage, root growth potential) parameters were assessed. The use of stabilized growing medium and lower densities resulted in higher quality seedlings of black locust, black and brutia pine, in terms of growth and physiological status. In the case of Italian cypress, the use of low density improved seedling morphological characters, but negatively affected its root growth potential. Moreover, this species performed better when peat was used. Correlation analysis showed that for brutia and black pine, seedling morphological traits reliably reflect seedling quality during the precultivation phase in mini-plugs. [ABSTRACT FROM AUTHOR]

Poor seed germination is a common phenomenon at suboptimal temperatures. Several priming treatments have been reported to enhance germination percentage under low-temperature sowings in various crop seeds. In this study, seed priming was carried out with KNO3, K2HPO4, and NaCl in concentrations of 0%, 1%, 2.5%, and 5% w/v and subsequent germination at incubation temperatures of 15 and 25°C on cucumber (Cucumis sativus L., cv. Super dominos) seed using a completely randomized design with three replications. Results indicated interaction between priming solution material, priming solution concentration, and incubation temperature affecting germination percentage, seedling fresh and dry weights, and seedling root volume. Priming did not benefit germination at 25°C. Priming with K2HPO4 at 15°C had little beneficial effect at higher solution concentrations and was generally less than all other materials at 15°C. When the priming material was KNO3, the control had seedling fresh weight values lower than the 1% and 5% concentrations. At 15°C, over all priming materials, seedling fresh weight, dry weight, and root volume were better than for controls. For K2HPO4 and KNO3 there were no differences in seedling dry weight between temperatures. For all priming materials seedling dry weight was lower at 15°C than at 25°C. It is recommended that KNO3 and NaCl be used as suitable priming material to enhance cucumber seed germination at low temperature. [ABSTRACT FROM AUTHOR]

The growth of 'Ridge Pineapple' sweet orange [Citrus sinensis (L.) Osbeck] seedlings and their susceptibility to Phytophthora root rot were studied under contrasting supplies of phosphate (Pi) or Phosphite (Phi). After 10 weeks of repeated applications of nutrient solutions, Phi concentrations were barely detectable in soil. Soil Pi was higher in Phi treatments than in pots that received Pi alone. Seedling growth was greatest when supplied with Pi or Phi separately, but when Pi and Phi were combined, growth was reduced to levels comparable to plants that received no P. Phi was found in both stems and leaves after it was applied to soil supporting the mobility of Phi within the plant. In addition, a small amount of Phi was found in roots after applications of Phi in foliar sprays. Different sources of soil-applied P did not affect the amount of Pi in roots, while the amounts of Pi in leaves were higher in plants that received Phi and Pi combined. Root resistance to Phytophthora root rot of citrus seedlings treated with Phi alone or in combination with Pi was greater than in plants treated with Pi alone, confirming the antifungal effect of Phi. [ABSTRACT FROM AUTHOR]

Angelica glauca Edgew. and Aconitum heterophyllum Wall., high value, endangered medicinal plants of the Himalayan region, have low germination rates and slow seedling growth. The present study examined the effect of a common seed surface disinfectant, sodium hypochlorite (NaHClO3), on seedling emergence, vigor, and survival of the above species. Seeds of A. glauca soaked (treated) in NaHClO3 for 30 min and seeds of A. heterophyllum soaked in NaHClO3 for 15 min had resulted in increased and more uniform emergence, better survival, and more vigorous seedlings than control seedlings not treated with the NaHClO3. In A. heterophyllum, soaking periods exceeding 15 min inhibited seedling growth. A seedling size index that considered plant height, collar diameter, and root length was used to determine the most effective treatment for increasing seedling size in the selected species. The NaHClO3 treatment, which is inexpensive, easily available, and a simple procedure, should be highly useful, especially for poor and unskilled farmers, in developing large scale planting material for exsitu cultivation and thus conservation of these species. [ABSTRACT FROM AUTHOR]

An attempt to improve the performance of rice (Oryza sativa L.) nursery seedlings through seed priming and its effect on the yield after transplantation was made in a field trial. Priming tools employed during the investigation include pre-germination, hydropriming for 48 h, osmohardening with KCl and CaCl2 (ψs-1.25 MPa) for 24 h, vitamin priming with 10 ppm ascorbic acid for 48 h and seed hardening for 24 h. All the priming techniques resulted in improved germination speed and spread, seedling fresh and dry weight, root and shoot length, number of secondary roots, seedling nitrogen, total sugars and α-amylase activity. Osmohardening with CaCl2 resulted in the best performance as indicated by improved germination speed and spread, seedling vigour and starch metabolism, followed by hardening and osmohardening with KCl. However, improved starch metabolism in coarse rice was observed in osmohardening with KCl. Higher K and Ca contents were observed in seeds osmohardened with KCl and CaCl2, respectively. Maximum straw and kernel yield and harvest index were recorded from osmohardening with CaCl2 in fine and osmohardening with KCl in coarse rice. Increased number of secondary roots and α-amylase activity were accompanied with increased seedling nitrogen and reducing sugars, respectively. [ABSTRACT FROM AUTHOR]

This research was aimed at evaluating the current water extraction methods for the analysis of four substrates treated with and without micronutrients. Black peat, coir, rice hulls, and pine bark (Pinus elliotis) were treated as follows: 1) control, 2) nitrogen, phosphorus, and potassium (NPK), and 3) NPK+M (micronutrients). Substrate samples were collected at 20 and 120 days of incubation for the determination of micronutrient concentrations. After 120 days of incubation, B, Mn, and Zn were easily detected in the SE, 1:1.5 v/v, and 1:2 v/v extracts from treatments with added micronutrients. Cu and Fe concentrations did not differ among treatments, irrespective of the extraction method used. Pine bark and black peat showed the lowest micronutrient concentrations for B and Zn; coir showed high values for B, Fe, and Zn concentrations; and rice hulls showed the highest Mn and Zn concentrations. SE and the 1:1.5 water extract were the best methods for substrate micronutrients evaluation. [ABSTRACT FROM AUTHOR]

On some reforestation sites, the planting of large-diameter seedlings can lower establishment costs by reducing the need to apply extra chemicals to increase the performance of regular seedlings. On five sites, survival of large-diameter Pinus taeda L. or P. elliottii Englem. seedlings (average root-collar diameter 8.1 to 9.2 mm) was equal or greater than for regular seedlings (average root-collar diameter < 5.3 mm) treated with extra chemicals. On three sites, diameters and/or heights of large-diameter seedlings were not significantly different from those of regular seedlings treated with operational applications of herbicides, fertilizers and insecticides. [ABSTRACT FROM AUTHOR]

A glasshouse study using Tephrosia vogelii was conducted on ferralsols with soil pH 5.0 and 5.9, and low available P (2.5-2.9 mg P kg soil-1), to assess the effects of soil pH and application of P on seedling performance and quantity and quality of biomass. The two soils were treated with Minjingu phosphate rock (MPR) at 0 and 400 mg P kg-1 soil and planted to T. vogelii, which grew for 12 weeks. The parameters assessed were plant height and nodule numbers for seedling performance, shoot and root dry matter yield for biomass quantity, and shoot N and P contents for biomass quality. Both soil pH and application of MPR significantly (p ≤ 0.05) affected all the parameters assessed. Increase in soil pH from 5.0 to 5.9 increased plant height by 13%, nodule number by 256%, shoot biomass by 110%, and N and P uptake by 121% and 125%, respectively. Minjingu PR application in the soil of pH 5.0 increased plant height by 14%, nodule number by 31%, shoot biomass by 94%, N uptake by 193% and P uptake by 200%. In the soil of pH 5.9 the corresponding increases due to MPR application were 5% for plant height, 65% for nodule number, 36% for shoot biomass, 35% for N and 100% for P uptake. The results indicated that in acidic ferralsols with low available P, biomass yield and quality of T. vogelii were enhanced when such soil conditions were corrected. [ABSTRACT FROM AUTHOR]

Contradictory results have been reported on the impact of needle nutrient concentration on frost hardiness in conifers. The aim of the present study was to test whether excessive nitrogen (N) supply would make seedlings of Picea abies (L.) Karst. more susceptible to autumn frost damage or lead to earlier bud break in the subsequent spring. Seedlings were grown in a greenhouse for one season and given a nutrient supply resulting in needle N concentrations ranging from 2.2 to 3.3%. Half of the seedlings with the lowest N fertilization were exposed to short day treatment for 3 weeks from mid August. No evidence was found in this experiment that excessive N concentrations in needles lead to increased autumn frost damage. Short day treatment resulted in less frost damage in autumn. No significant difference in time of bud break due to fertilization or day length was detected. This may have been due to a more uniform bud break caused by the storage and growth conditions. [ABSTRACT FROM AUTHOR]

Studies the use of seedling root and coleoptile length as selection criteria for field emergence in pearl millet. Key issues of interest; Analysis of pertinent topics and relevant issues; Implications on sustainable agriculture.