Root Dry Mass Research Articles

Response of sunflower seeds (Helianthus annuus L.) to different concentrations of metals and doses of gamma radiation (241Am)

The sunflower crop (Helianthus annuus L.) presents great tolerance to heavy metals and in pre-determined doses of gamma (γ) radiation it presents gains in plant increments. This study aimed to evaluate the response to doses of γ radiation and different concentrations of toxic metals in the vegetative development of sunflower. Mirasol sunflower seeds were subjected to different doses of 241Am γ rays and concentrations of Aluminum, Cerium and Copper (mg L-1). Sunflower plants were evaluated only in the vegetative period for germination, aerial length, root length, aerial and root fresh mass, aerial and root dry mass. The doses of γ radiation promoted increases in the variables in the vegetative phase, especially for 5 and 10 minutes of exposure to γ rays. The concentrations of the toxic elements Al and Ce showed significant differences in all increments, however, doses higher than 85 mg L-1 demonstrated losses in length and mass of sunflower plants. For the Cu element, the doses did not have a significant effect, these being non-significant and the cultivar Mirasol resistant. Future studies should be carried out evaluating the reproductive phase and its gains in increasing biomass and production.

Herbicides in the initial growth and chlorophyll indices of sugarcane in pre-sprouted seedlings

The aim of the present study was to assess the selectivity of herbicides applied in the pre and post-planting of pre-sprouted seedlings (PSS). The experiment was conducted in a greenhouse, using a completely randomized design, with nine treatments and four repetitions. The IACSP95-5000 cultivar was used. The treatments consisted of herbicides applied in five doses as follows: in pre-planting: sulfentrazone, diclosulam, imazapic, and imazapyr, in post-planting: ethoxysulfuron, halosulfuron, 2,4-D and MSMA, and a control treatment without herbicide. Injury symptoms were assessed at 7, 15, 30, 45, 60, 75, and 90 days after application (DAA), height, diameter, number of tillers, chlorophyll A, B, and total chlorophyll at 30, 60, and 90 DAA, leaf area, shoot and root dry mass at 90 DAA. The post-emergent herbicides were considered selective. Pre-planting herbicides reduced the variables assessed at 90 DAA, observed by linear regression for diclosulam and imazapic, and exponential regression for imazapyr. Treatments with sulfentrazone caused few injury symptoms, with subsequent recovery. In addition, all the variables analyzed were equal to control, with the sulfentrazone considered selective for the IACSP95-5000 cultivar.

Genetic diversity and candidate genes for transient waterlogging tolerance in mungbean at the germination and seedling stages.

Mungbean [Vigna radiata var. radiata (L.) Wilczek] production in Asia is detrimentally affected by transient soil waterlogging caused by unseasonal and increasingly frequent extreme precipitation events. While mungbean exhibits sensitivity to waterlogging, there has been insufficient exploration of germplasm for waterlogging tolerance, as well as limited investigation into the genetic basis for tolerance to identify valuable loci. This research investigated the diversity of transient waterlogging tolerance in a mini-core germplasm collection of mungbean and identified candidate genes for adaptive traits of interest using genome-wide association studies (GWAS) at two critical stages of growth: germination and seedling stage (i.e., once the first trifoliate leaf had fully-expanded). In a temperature-controlled glasshouse, 292 genotypes were screened for tolerance after (i) 4 days of waterlogging followed by 7 days of recovery at the germination stage and (ii) 8 days of waterlogging followed by 7 days of recovery at the seedling stage. Tolerance was measured against drained controls. GWAS was conducted using 3,522 high-quality DArTseq-derived SNPs, revealing five significant associations with five phenotypic traits indicating improved tolerance. Waterlogging tolerance was positively correlated with the formation of adventitious roots and higher dry masses. FGGY carbohydrate kinase domain-containing protein was identified as a candidate gene for adventitious rooting and mRNA-uncharacterized LOC111241851, Caffeoyl-CoA O-methyltransferase At4g26220 and MORC family CW-type zinc finger protein 3 and zinc finger protein 2B genes for shoot, root, and total dry matter production. Moderate to high broad-sense heritability was exhibited for all phenotypic traits, including seed emergence (81%), adventitious rooting (56%), shoot dry mass (81%), root dry mass (79%) and SPAD chlorophyll content (70%). The heritability estimates, marker-trait associations, and identification of sources of waterlogging tolerant germplasm from this study demonstrate high potential for marker-assisted selection of tolerance traits to accelerate breeding of climate-resilient mungbean varieties.

Perspective herbicides for post-sowing use in narrow-leafed lupin crops

Technical and economic efficiency of Pilot herbicide when applied on green leaf in narrow-leafed lupine crops was studied. The research was conducted in field and plot experiments according to the generally accepted methods in the southwestern part of the Non-Chernozem zone of Russia. The soil of the experimental field was gray forest light loamy in mechanical composition. The following application rates of the preparation were used: 1.5, 2.0 and 2.5 l/ha in the phase of appearance of two true leaves in lupine. The following plants showed high sensitivity even at the minimum application rate: cleavers (Galium aparine L.), wild buckwheat (Fallopia convolvulus L.), lamb's-quarters (Chenopodium album L.), one of the types of hemp nettle (Galeopsis sp. L.), shepherd's purse (Capsella bursa pastoris L. Medik), field violet (Viola arvensis Murr.), chickweed (Stellaria media L.). Application of GalactAlt graminicide (application rate 1.0 l/ha) after treatment of narrow-leafed lupine crops with Pilot herbicide promoted almost complete destruction of annual grass weeds. Application of Pilot herbicide had a favorable effect on nitrogen content in both dry aboveground mass and root mass of lupine. Reduction of weediness of crops when using Pilot contributed to the increase in lupine yield. In the variant with the application of 1.5 l/ha of the herbicide, the average yield of narrow-leafed lupine seeds exceeded the control by 0.53 t/ha in three years of the trials. The highest increase in seed yield of narrow-leafed lupine (0.96 t/ha) was observed in the variant that involved the application of herbicide Pilot at a concentration of 1.5 l/ha in the phase of one or two true leaves in lupine and herbicide GalactAlt at a concentration of 1.0 l/ha in the phase of lupine budding. Chemical analyses showed an increase in crude protein content in narrow-leafed lupine seeds by 2.3–4.2% when the crops were treated with Pilot herbicide compared to the control variant, where the treatment was not carried out.

Effects of root-applied biochar on soil nitrogen transformation and root nitrogen metabolism of cucumber seedlings in facility continuous cropping soils.

The problem of soil barrier caused by excessive accumulation of nitrogen is common in continuous cropping soil of facility agriculture. To investigate the modulating effects of biochar amendment on soil nitrogen transformation in greenhouse continuous cropping systems, we conducted a pot experiment with two treatments, no biochar addition (CK) and 5% biochar addition (mass ratio). We analyzed the effects of biochar addition on soil microbial community structure, abundances of genes functioning in nitrogen cycling, root growth and nitrogen metabolism-related genes expressions of cucumber seedlings. The results showed that biochar addition significantly increased plant height, root dry mass, total root length, root surface area, and root volume of cucumber seedlings. Rhizosphere environment was improved, which enhanced root nitrogen absorption by inducing the up-regulation of genes expressions related to plant nitrogen metabolism. Biochar addition significantly increased soil microbial biomass nitrogen, nitrate nitrogen, and nitrite nitrogen contents. The abundances of bacteria that involved in nitrogen metabolism, including Proteobacteria, Cyanobacteria, and Rhizobiales (soil nitrogen-fixing bacteria), were also significantly improved in the soil. The abundances of genes functioning in soil nitrification and nitrogen assimilation reduction, and the activities of enzymes involved in nitrogen metabolisms such as hydroxylamine dehydrogenase, nitronate monooxygenase, carbonic anhydrase were increased. In summary, biochar addition improved soil physicochemical properties and microbial community, and affected soil nitrogen cycling through promoting nitrification and nitrogen assimilation. Finally, nitrogen adsorption capacity and growth of cucumber plant was increased.

Effect of axillary bud number on stem cuttings of sweet potato cv. 'Blesbok' productivity using sack gardening technology

Increasing urbanisation and the rise in global food prices, which results in severe hunger and micronutrient deficiencies, necessitates the identification of innovative, but affordable vegetable growing-based strategies, that can increase access to food by utilising the limited space available in rural and urban areas. Therefore, sack gardening technology could be a solution to both the lack of arable land and water scarcity in urban and rural areas. The objective of the study was to determine whether axillary bud number will have an effect on the agronomic parameters of sweet potato cv. 'Blesbok' produced using the sack gardening technology. The number of axillary buds per stem cutting, namely, 1 (control), 2, 3, 4, and 5 buds, were arranged in RCBD, with 10 replicates. The number of axillary buds had significant effects on vine length (VL), fresh shoot mass (FSM), number of shoots (NOS) and dry shoot mass (DSM). However, no significant effects were observed on fresh tuberous root mass (FTRM), chlorophyll content (CC), stem diameter (ST), tuberous root diameter (TRL), tuberous root length (TRL), dry tuberous root mass (DTRM) and number of tuberous roots (NTR). Relative to the control VL, FSM and DRM was reduced by 8-37, 30-55 and 26-55%, in stem cuttings having 2, 3, 4 and 5 buds, respectively, whereas the NS was increased by 8-17%. The quadratic relationship models were explained by 95, 92, 96 and 98% in VL, NOS, FSM and DSM, respectively. In conclusion, stem cuttings containing 1 and 2 axillary buds showed better growth parameters when grown under sack gardening technology.

Agronomic performance of plant growth-promoting microorganisms and nitrogen sufficiency index in common bean

This work aimed to assess Rhizobium tropici, Azospirillum brasilense, and Trichoderma asperellum co-inoculation effects, besides N-fertilizer supplementation as determined by the nitrogen sufficiency index (NSI) on the development of common bean. Field trials were carried out in a randomized block design with four replicates at three different locations. Treatments consisted of sole or combined inoculation of R. tropici, A. brasilense, and T. asperellum, besides N-fertilization. Seeds were inoculated with R. tropici and/or T. asperellum using 10 g of each inoculant kg−1 of seed. At the phenological stage V2/V3 A. brasilense was inoculated using 300 ml ha−1. Nitrogen sufficiency index (NSI), number of nodules (NN), nodule dry mass (NDM), root dry mass (RDM), shoot dry mass (SDM), number of pods (NP), number of grains (NG), and grain yield (GY) were assessed. NN and NDM were higher under R. tropici, A. brasilense, and T. asperellum co-inoculation. This same co-inoculation provided RDM and SDM similar to the use of 120 kg ha−1 of N. R. tropici, A. brasilense, and T. asperellum co-inoculation supplemented with N-fertilizer at the phenological stage R5, provide NP and NG similar to 120 kg ha−1 N, and to 80 kg ha−1 N supplemented with N at the phenological stage V4. NSI was effective to determine the N needs of common bean. The co-inoculation of two doses ha−1 of R. tropici, three doses ha−1 of A. brasilense and two doses ha−1 of T. asperellum, supplemented with N-fertilizer at phenological stage V4 based on NSI, stimulated growth and yield components of common bean, providing GY equivalent to the N-fertilized treatments.

Sulfur Supplementation Enhanced the Growth and Photosynthesis of Lettuce in Hydroponic Production Using One-bag Complete Fertilizer

Sulfur (S) is an essential plant nutrient that regulates plant growth and metabolism. However, S is often absent from certain one-bag hydroponic fertilizers designed to provide a complete and balanced mixture of nutrients. We quantified the effects of S supplementation on the growth, morphology, and photosynthesis of lettuce grown in a deep-water culture hydroponic system. Two lettuce (Lactuca sativa) cultivars, green butterhead Rex and red oakleaf Rouxai, were grown using a prepackaged fertilizer specially formulated for reverse osmosis (RO) and other low-alkalinity water sources. The base nutrient solution was mixed using Jack’s FeED 12–4–16 fertilizer and RO water at a nitrogen concentration of 100 mg⋅L−1 (control). Three S supplementation treatments were implemented over a 4-week production period: 10 mg⋅L−1 supplemental S (provided using MgSO4); 20 mg⋅L−1 supplemental S (MgSO4); and a treatment using H2SO4 (instead of nitric acid) for pH adjustment. In both lettuce cultivars, shoot fresh and dry mass, total leaf area, leaf photosynthetic rate, total chlorophyll content, and leaf S concentration with all three S supplementation treatments increased significantly compared with those of the control. In contrast, the ratio of shoot dry mass to fresh mass, root dry mass, and percentage of root dry mass (i.e., root dry mass/total shoot and root mass) were significantly higher with the control treatment. Notably, ‘Rouxai’ lettuce grown in the control treatment had intense red coloration with a 216.6% to 288.9% increase in the anthocyanin index. There were no statistical differences in any of the growth and morphological parameters among the three S supplementation treatments. Overall, we observed significantly enhanced lettuce growth and photosynthetic performance with S supplementation, resulting in a 144.0% to 215.9% increase in shoot fresh mass in the two cultivars compared with the control. Thus, we recommend that at least 10 mg⋅L−1 of S should be supplemented when growing lettuce hydroponically to ensure optimal plant growth, especially when S is absent or low in the fertilizer and water source.

Differences of waterlogging tolerance in winter pulse crop between emergence and vegetative stages

AbstractPulse production is decreased when grown on waterlogged soil in rice‐based cropping. This study evaluated four pulse crops—grass pea, field pea, cowpea and lentil—to find out their responses to waterlogging (WL) stress at emergence and vegetative stages. The treatment levels at emergence were drained control, 4‐, 7‐ and 10‐day WL, while in the vegetative stage they were drained control, 6‐, 10‐ and 14‐day WL. In the emergence stage, %emergence was significantly reduced as WL duration increased. After 10‐day WL, emergence was reduced to 65% for grass pea, 30% for field pea, 5% for lentil and 7% for cowpea. At the vegetative stage, in both the WL and recovery phases, the WL treatment reduced plant height, tap root length, shoot and root dry mass compared to those in drained control with a significant difference in crops. In recovery as compared to the WL phase at 14‐day WL, the chlorophyll content was increased 15% in cowpea and 14% in grass pea but decreased in field pea (26%) and lentil (35%). Similarly, in the recovery phase at 14‐day WL, shoot relative growth rates (RGRs) of cowpea, grass pea, field pea and lentil were 20, 66, 10 and 5 mg plant−1 d−1; which were 66%, 70%, 8% and 14% of drained control, respectively. The RGR of root at 14‐day WL was also higher in cowpea and grass pea with the rate of 13.8 and 16 mg−1 plant−1 d−1, respectively; in sharp contrast to a reduction of −4.3 mg−1 plant−1 d−1 in field pea and −3.9 mg−1 plant−1 d−1 for lentil than drained control. Furthermore, the higher number of adventitious roots was found in cowpea (14) and grass (9) pea than in field pea (6) and lentil (4). Comparison between growth stages, grass pea was tolerant to WL in both stages. Cowpea was WL sensitive at emergence, but tolerant to vegetative stage. Field pea was moderately tolerant to emergence but was sensitive at vegetative stage. Lentil was sensitive at WL at both stages. These novel insights will allow the fitting of winter pulses to various cropping systems according to the perceived risk of WL at various growth stages.

Fertirrigação com cobre na cultura da beterraba em região semiárida

ABSTRACT Copper is an essential element for beet; however, it needs to be made available in adequate quantities since this nutrient, which is a heavy metal, can cause toxicity to plants and/or humans. This study aimed to evaluate the agronomic performance of beet fertigated with copper in a semi-arid region of Brazil. Two experiments were carried out in complete randomized blocks, with five treatments (0, 1.5, 3.0, 4.0, and 6.0 kg ha-1 of copper) and four replicates. In 2019, the copper content was within the adequate range for beet. In 2021, fertigation with copper above 0.8 kg ha-1 led to contents in the phytotoxicity range, which may explain the reduction in total and tuberous root dry mass accumulation. Fertilization with copper increased marketable yield in 2019 (17.32 t ha-1 at the dose of 3.9 kg ha-1 of copper), while, in 2021, there was no fit of the equations. Copper fertilization altered the tuberous root pH but did not influence the other tuberous root quality components. Plants fertilized with copper accumulated more copper in the leaves than in the tuberous root, with a maximum accumulation of 6.0 kg ha-1 of copper in 2019 and 2021. Fertilization with 3.9 kg ha-1 suits soils with low copper content.

Growth and Morphophysiological Responses of Protium heptaphyllum Seedlings to Root Deformation and Light Availability

Abstract J-root deformation caused at the time of pricking out is highlighted in several forest nursery manuals, but there are few reports in the literature on the consequences of this type of root deformation on the physiology and growth of tree seedlings. Protium heptaphyllum is a tropical tree with potential for use in forest enrichment projects and agroforestry systems. This study aimed to evaluate the biomass allocation, root hydraulic conductivity and growth of P. heptaphyllum seedlings subjected to root deformation and three contrasting light levels (44%, 28%, and 2% of full sunlight) over a period of 155 days. Root deformation negatively affected the shoot to root dry mass ratio (S/R), the diameter to root volume ratio (D/RV), the height to root volume ratio (H/RV) and relative growth rate (RGR). Seedlings at 44% and 28% of full sunlight had lower S/R and higher hydraulic conductivity per unit of root volume (Kr/RV), net assimilation rate (NAR), and RGR when compared with seedlings at 2% of full sunlight. No significant interactions were observed between root deformation and light. Root deformation caused at the time of pricking out affects the quality of seedlings, decreasing growth rates and changing morphophysiological characteristics independently of light availability. Study Implications: Poor quality tree seedlings with J-root deformation is a problem frequently pointed out in forest nursery manuals. Despite this, there is scarce information in the literature on how errors in the pricking out process affect the morphology and physiology of tree seedlings. We demonstrated that this type of root deformation decreases the growth rate and changes important characteristics of Protium heptaphyllum seedlings regardless of light environment. We highlight important morphological and physiological effects of errors in the management of tree seedlings, which are frequently pointed out in forest nursery manuals but have not been demonstrated by experimental studies.

CO2 elevation and N fertilizer supply modulate leaf physiology, crop growth and water use efficiency of maize in response to progressive soil drought

AbstractElevated atmospheric CO2 concentration (e[CO2]) and varied nitrogen (N) fertilization levels may mediate the different responses of C4 crops to progressive soil drought. In this study, the effects of reduced N (N1, 0.8 g pot−1) and adequate N (N2, 1.6 g pot−1) supply on leaf physiology, plant growth and water use efficiency (WUE) of maize (C4 crop) exposed to progressive soil drought grown at ambient CO2 (a[CO2], 400 ppm) and elevated CO2 (e[CO2], 800 ppm) concentration were investigated. The results indicated that compared with a[CO2], net photosynthetic rate (An) and leaf water potential (Ψl) at e[CO2] were maintained in maize leaves, while stomatal conductance (gs), transpiration rate and leaf hydraulic conductance were decreased, leading to enhanced WUE from stomatal to leaf scale. Despite An and Ψl of e[CO2] plants were more sensitive to progressive soil drought under both N fertilization levels, e[CO2] would increase leaf ABA concentration ([ABA]leaf) but decline the gs response to [ABA]leaf under N1 supply. e[CO2] coupled with N1 fertilization was conducive to enlarging leaf area, promoting specific leaf area, root and total dry mass, whereas reduced stomatal aperture and plant water use under progressive drought stress, contributing to an improvement in plant WUE, implying a better modulation of maize leaf stomata and water status under reduced N supply combined with e[CO2] responding to progressive soil drought. These findings in the current study would provide valuable advice for N management on maize (C4) crop efficient water use in a drier and CO2‐enriched environment.

Effect of concentrations, times of sweet algae extract applications on soybean development and productivity

In the literature there are works focused on studies of marine algae applied to soybean culture, however, little is known about the application of freshwater algae extracts in the culture, being necessary more in-depth studies about the benefits of these products of natural origin. The objective was to evaluate the effect of application periods and increasing concentrations of freshwater seaweed extract on the agronomic components of soybean. The experiment was set up in the experimental unit of the Federal University of Tocantins, with a randomized block design with four repetitions, in a 7x4+1 factorial scheme, with the first factor consisting of seven periods of application (V3, V3V7, V3R2, V3V7R2, V7, V7R2 and R2) and the second, four concentrations (0.5%, 1.0%, 1.5%, 2.0%), plus a control treatment without application of the extract. The cultivar used was 8579 RSF. The characteristics evaluated were: plant height, number of pods per plant, number of grains per plant, number of grains per pod, weight of grains per plant, dry mass of the aerial part and root. The seaweed extract did not show significance for the evaluated characteristics, except for the root dry mass, where it showed a negative effect when applied at V3 stage, where the plants showed a reduction in mass when compared to the R2 stage, for the concentration of 1.5%.

Biometry and physiological potential of Pterogyne nitens Tull. Seeds as a function of different substrates

The Pterogyne nitens Tul., popularly known as "amendoim-bravo," belongs to the Fabaceae family and can be used in the recovery of degraded areas and in the restoration of riparian forests. The objective of this study was to biometrically characterize the seeds of "amendoim-bravo" and study the influence of substrates on the physiological potential of the seeds. For biometric characterization, eight replicates of 100 seeds were used to determine length and width. In the germination test using a completely randomized experimental design, the seeds were distributed in five different substrates: paper towel in roll form, between blotting paper, on top of blotting paper, between sand, and commercial substrate, at a regulated temperature of 30°C in a Biochemical Oxygen Demand (B.O.D) chamber. The first germination count (PCG), germination speed index (IVG), root length, shoot length of seedlings, dry root mass, and shoot mass of seedlings were analyzed. Evaluating the first germination count and germination index, the paper towel roll substrate showed superiority with 96% and 98%, respectively, statistically differing from the other treatments. The value for germination speed index also highlighted the use of the paper towel roll (6.347). Regarding mean time, mean speed, and synchrony, the best results were also achieved with the paper towel roll substrate. Pterogyne nitens Tul. seeds have an average length of 11.52 mm and a width of 6.35 mm. For evaluating physiological potential, the use of the paper towel roll substrate is recommended.

Effect of a QTL on wheat chromosome 5B associated with enhanced root dry mass on transpiration and nitrogen uptake under contrasting drought scenarios in wheat.

A sufficient nitrogen supply is crucial for high-quality wheat yields. However, the use of nitrogen fertilization can also negatively influence ecosystems due to leaching or volatile atmospheric emissions. Drought events, increasingly prevalent in many crop production areas, significantly impact nitrogen uptake. Breeding more efficient wheat varieties is necessary to achieve acceptable yields with limited nitrogen and water. Crop root systems play a crucial role as the primary organ for absorbing water and nutrients. To investigate the impact of an enhanced root system on nitrogen and water use efficiency in wheat under various irrigation conditions, this study conducted two experiments using precision phenotyping platforms for controlled drought stress treatment. Experiment 1 involved four contrasting winter wheat genotypes. It included the Chinese variety Ning0604, carrying a quantitative trait locus (QTL) on chromosome 5B associated with a higher root dry biomass, and three elite German varieties, Elixer, Genius, and Leandrus. Experiment 2 compared near-isogenic lines (NIL) of the three elite varieties, each containing introgressions of the QTL on chromosome 5B linked to root dry mass. In both experiments, nitrogen partitioning was tracked via isotope discrimination after fertilization with 5 Atom % 15N-labeled KNO3-. In experiment 1 the quantification by 15N isotope discrimination revealed significantly (p < 0.05) higher nitrogen derived from fertilizer in the root organ for Ning0604 than those of the three German varieties. In experiment 2, two out of three NILs showed a significantly (p < 0.05) higher uptake of N derived from fertilizer than their respective recipient line under well-watered conditions. Furthermore, significantly lower transpiration rates (p < 0.1) were observed in one NIL compared to its respective recipient. The combination of the DroughtSpotter facility coupled with 15N tracer-based tracking of N uptake and remobilization extends the insight into the impact of genetically altered root biomass on wheat NUE and WUE under different water availability scenarios. The study shows the potential for how a modified genetic constitution of the locus on wheat chromosome 5B can reduce transpiration and enhance N uptake. The dependence of the observations on the recipient and water availability suggests a need for further research to investigate the interaction with genetic background traits.

Morph-physiology and development of soybean cultivars under irrigation shift

During certain periods of the year, some Brazilian regions impose water restrictions, initiating the growth cycle of the soybean crop. Thus, this work was conducted aiming to evaluate the morphophysiology and development of soybean cultivars under irrigation intervals. The experiment was conduct in January 2021, in a rural property, located in the municipality of Lavínia, state of São Paulo, Brazil. The design was completely randomized, in a 2×5 factorial scheme, with two soybean cultivars, M7110IPro (Monsoy®) and Desafio RR8473RSF (Brasmax®), interacting with the irrigation intervals (i.e., 24 h (Control); 48 h; 72 h, 96 h and 120 h) totalizing 10 treatments. We used four repetitions per treatment, which totalizes 40 plots or pots. Our results revealed that intervals longer than 48 h already negatively influence in morphophysiology of the soybean crop. Intervals of 96 h caused greater negative interferences on plant height (PH); number of leaflets (NL); number of pods (NP); dry mass of aerial part (DMAP) and root (DMR) in the soybean crop when grown in pots. Water stress did not influence the stomatal density of soybean grown in pots. Water stress harms soybean physiological parameters. No soybean cultivar showed tolerance to water stress.

Toxic effect of elements on the germination and initial development of barley seeds (Hordeum vulgare L.)

Barley (Hordeum vulgare) is an agricultural vegetable from the Poaceae family used in food and beer production. The study aimed to evaluate the toxic effect of Aluminum (Al) and Copper (Cu) on germination and initial development in barley seeds cultivar KWS Irina. Different concentrations (0, 35, 85 and 125 mg L-1) of aqueous solution of Al and Cu were produced from their chlorides. The toxicity experiment was carried out in a germination box maintained in a germination chamber with a 12-h photoperiod. After 15 days of germination, the seedlings were measured using a millimetric ruler (cm) where they were evaluated for plant length, root length, and fresh and dry mass of plant and root determined on a digital analytical scale (g). Barley seedlings cultivar KWS Irina demonstrated to be intolerant to concentrations of the toxic elements Al and Cu in all plant parameters analyzed, except for plant dry mass. Future studies should be carried out comparing the initial and reproductive development of this barley cultivar in terms of the presence and absence of toxic elements.

The impact of PEG-induced drought stress on early vigour traits of bread wheat

ABSTRACT A total of 11 genotypes from the collection of 101 bread wheat genotypes, with desirable traits in terms of increased tolerance to drought, were chosen for parents and eight crosses were performed. Number of seminal roots (NSR), total root length (TRL), root dry mass (RDM), number of shoots per plant (NS), main shoot length (MSL), shoot dry mass (SDM), number of leaves per plant (NL), leaf area per plant (LA), leaf dry mass (LDM), aboveground dry mass (ADM), SDM/LDM, RDM/ADM were analysed at the boot stage (Z45). The F1 progeny had on average higher mean values (P < 0.001) than parents for four traits: RDM, NS, LA and RDM/ADM. The highest broad sense heritability values were determined for RDM (97.6%) and NSR (93.9%). Factor analysis indicated that a large root system, higher RDM and TRL are associated with higher NS, NL, LA and LDM. For Euclid x CHI-4 and WWBMC2 x Ingenio combinations the highest heterosis values were observed for TRL (34.1%) and SDM (23.7%), for RDM (28.6%) and LA (26.8%), respectively. PEG-induced drought stress in the seedling stage, in most of the new germplasm, caused an increased redistribution of dry matter in the root compared to the stem.

Biomass partitioning reveals the adaptability of tiger nut (Cyperus esculentus L.) in an arid ecosystem in Inner Mongolia, China

AbstractTiger nuts (Cyperus esculentus L.) have been widely cultivated as a bioenergy crop in northern China. The value of tubers is receiving special attention, but the lack of information on how organs of tiger nuts coordinate resources to adapt to arid environments has limited the potential tuber production and diverse use. To address this knowledge gap, we experimented in the Ulan Buh Desert, Inner Mongolia (106° 33′ 28″ E, 40° 27′ 32″ N). Three fertilizer treatments were applied: zero fertilizer (N:P = 0:0), traditional fertilizer (N:P = 15:15), and additional nitrogen fertilizer (N:P = 60:15). Investigations were conducted at seedling, rhizome production, tuber formation, and tuber maturation stages. The results showed that under zero fertilizer, tiger nuts allocated biomass predominantly to propagative organs, namely rhizomes and tubers. However, an increase in leaf area or root surface area would necessitate more investment in leaf or root dry mass, resulting in diminishing returns. For biomass allocation, tiger nut responded the same way to traditional fertilizer treatment and zero fertilizer treatment, but the tuber number and yield increase under traditional fertilizer application. Additional nitrogen fertilizer stimulated shoot production through accelerated rhizome production aided by leaf area increasing. Fertilizer application can significantly increase both the number of tiger nuts and tuber yield. Nitrogen addition positively influenced aboveground biomass and enhanced rhizome tillering. Strong adaptability of tiger nuts makes the plant a suitable pioneer crop for developing marginal lands. The robust aboveground growth after nitrogen application enhances suitability for pasture utilization.

Supplementary Light on the Development of Lettuce and Cauliflower Seedlings

The production of seedlings is one of the main activities for implementing agricultural crops. Many factors are involved in producing quality seedlings, including nutrition, health, genetics, and climatic factors such as temperature, humidity, and light. To evaluate the effect of light supplementation, a study was conducted using supplementary artificial light to produce lettuce and cauliflower seedlings. Sowing was carried out in styrofoam trays under a floating irrigation system. Part of the experiment containing the two species, received treatment with LED light for an additional 4 h per day, in addition to solar radiation (10 h∙day−1). The remaining seedlings received only solar radiation (without supplementation). After 37 days, the seedlings’ biometric (leaf area, root length, aerial dry mass, and root dry mass) and biochemical parameters (phenolic compounds, flavonoids, chlorophyll a/b, and total chlorophyll) were analyzed. The data showed that the complementary light enhanced the performance in all the biometric parameters evaluated in the experiment for lettuce and cauliflower. The biochemical parameters in lettuce were also higher in seedlings with light supplementation. For cauliflower, supplementary light did not differ from the natural photoperiod for biochemical parameters except for a reduction in the levels of total phenolic compounds. Considering the enhanced biometric and biochemical parameters and greater dry weight and leaf area of the seedlings grown with supplemental light, using such a tool can optimize seedling development, possibly reducing production time in the nursery and providing greater productivity.