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Drought stress adversely impacts growth, crop production, reproductive organ development, and yield characteristics in maize. As a drought-sensitive crop, maize (Zea mays L.) shows considerable varietal differences. A study was conducted at the Tissue Culture Laboratory, Department of Biology, Faculty of Mathematics and Natural Sciences, University of North Sumatra, Medan, Indonesia in order to identify drought-tolerant maize varieties. During germination and early seedling growth, 16 local accessions were evaluated for drought tolerance. Based on local climate and soil conditions, these specific accessions were chosen. The varieties were tested against five levels of drought stress imposed by Polyethylene glycol 6000 (PEG-6000) at 10, 20, 30, 40, and 50%. An experiment with three replications was conducted using a completely randomized design. In the study, local maize accessions (BI3, SB5, DS2, and MN3) and the hybrid variety (H) showed the capability of tolerating drought stress. Generally, germination time, germination percent and vigor index, root and shoot length, shoot ratio, and fresh and dry weight were decreased by increasing PEG concentrations (up to 50%). According to ANOVA results, shoot water content was not significantly affected by the PEG, nor was the interaction between the PEG and the accessions. The root water content, however, was significantly affected by PEG, and the interaction between PEG and accessions. Although interactions between accessions with low PEG concentrations improved germination characteristics, the root histology of the accessions varied. According to drought tolerance indexes, five maize accessions are drought-tolerant, including H (0.683), SB5 (0.617), DS2 (0.565), MN3 (0.512), and BI3 (0.504). The drought-tolerant varieties are recommended in regions with low rainfall or low water sources since they are less water-intensive and produce higher yields.

Over the past few decades, numerous studies investigated the vigor and productivity of fruit species depending on the rootstock on which they were grafted, but the exact size-controlling mechanism itself has not been fully elucidated, nor were the rapid rootstock selection methods defined. Thus, this study aimed to assess the root anatomical characteristics and their influence on the overall 'Summit' cherry tree vigor to confirm the size-controlling effect and establish an effective protocol for rapid rootstock selection. Plant material included three cherry species (Prunus cerasus, Prunus fruticosa, and Prunus mahaleb) and interspecific hybrid 'Gisela 5′ (P. cerasus × Prunus canescens) as a control. The detailed anatomical analysis included root samples with the differentiated secondary structure taken from the sampling depth of 10–15 cm. Roots with percentages of vessels ≈40%, ≈50%, and ≈10% belonging to size-classes ˂700 µm2, 700–2000 μm2, and ˃2000 µm2 (respectively) are presumed to provide optimal amounts of water solution to the scion, without compromising plant vitality, drought tolerance, and size-controlling effect. Statistically significant correlations were determined between anatomical properties (the percentage of vessels, especially ˃2000 µm2, xylem porosity, and hydraulic conductivity, both per mm2 and total root) and vegetative growth in the juvenile vegetative phase, indicating direct vessel size influence on plant vigor and its employment in size-controlling cherry rootstock selection. [ABSTRACT FROM AUTHOR]

Copper (Cu) is an essential micronutrient for plants, but when present in excess, it induces toxicity. In this study, cuttings of four wine-producing varieties of Vitis vinifera L. were used: 'Tinta Barroca', 'Tinto Cão', 'Malvasia Fina' and 'Viosinho'. The grapevine cuttings were distributed by hydroponic solutions enriched with different Cu concentrations (1, 10, 25 and 50 μM) plus control. At the end of the experiment, the root growth was evaluated, and individual roots were collected, fixed, and used for histological sections and chromosome spreads preparation. The higher Cu concentrations induced toxicity and inhibited root growth. However, the grapevine varieties responded with the thickening of the root exodermis and endodermis. In the chromosome spreads, normal and abnormal interphase and mitotic cells were observed in all varieties and treatments. The increase of Cu concentration decreased the nucleolar activity, as seen by reducing the nucleolar number and area. It increased the frequency of interphase cells with anomalies (ICA), but it did not influence total soluble protein concentration. The augment of Cu concentration also decreased the mitotic index (MI) and increased the percentage of dividing cells with anomalies (DCA). Different types of chromosomal anomalies in all mitotic phases, treatments and varieties were found. Overall, the white wine varieties, 'Malvasia Fina' and 'Viosinho', appeared to be more tolerant to the Cu-induced stress because they showed higher root growth and mean MI and lower mean DCA than the red wine varieties. • Cu inhibited root growth and induced thickening of the exodermis and endodermis. • Cu toxicity decreased the nucleolar activity. • Cu treatment increased the frequency of interphase/dividing cells with anomalies. • Cu toxicity increased root vacuolization. • White wine grapevine varieties appear more tolerant to Cu-induced stress. [ABSTRACT FROM AUTHOR]

Over the past few decades, numerous studies investigated the vigor and productivity of fruit species depending on the rootstock on which they were grafted, but the exact size-controlling mechanism itself has not been fully elucidated, nor were the rapid rootstock selection methods defined. Thus, this study aimed to assess the root anatomical characteristics and their influence on the overall ‘Summit’ cherry tree vigor to confirm the size-controlling effect and establish an effective protocol for rapid rootstock selection. Plant material included three cherry species (Prunus cerasus, Prunus fruticosa, and Prunus mahaleb) and interspecific hybrid ‘Gisela 5′ (P. cerasus × Prunus canescens) as a control. The detailed anatomical analysis included root samples with the differentiated secondary structure taken from the sampling depth of 10–15 cm. Roots with percentages of vessels ≈40%, ≈50%, and ≈10% belonging to size-classes ˂700 µm2, 700–2000 μm2, and ˃2000 µm2 (respectively) are presumed to provide optimal amounts of water solution to the scion, without compromising plant vitality, drought tolerance, and size-controlling effect. Statistically significant correlations were determined between anatomical properties (the percentage of vessels, especially ˃2000 µm2, xylem porosity, and hydraulic conductivity, both per mm2 and total root) and vegetative growth in the juvenile vegetative phase, indicating direct vessel size influence on plant vigor and its employment in size-controlling cherry rootstock selection.

The present manuscript has focused on the heavy metal; accumulation potential by common native plants i.e. Chenopodium album L., Ricinus communis, Ranunculus sceleratus, and Rumex dentatus growing on the disposed of pulp and paper mill effluent sludge. The sludge showed the abundance of benzene propanoic acid tert- butyldimethylsilyl ester, Octadecanoic acid, TMS, Hexadecanoic acid, TMS, cinnamic acid-α-phenyl-TMS ester, β-sitosterol TMS, 4-mercaptobenzoic acid as residual complex organic compounds along with heavy metals Fe (98.30 mg/L−1), Zn (51.00 mg/L−1), Cu (3.21 mg/L−1), Cd (9.11 mg/L−1), Mn (18.27 mg/L−1), Ni (5.21 mg/L−1), (Hg 0.014 mg/L−1) which were above the prescribed limit of environmental standard. The complexation of organic compounds with heavy metal restricts the bioavailability of metals to plants. But the metal analysis in various parts of the plant showed a significant amount of metal accumulation. Further, histological observations of root tissue through TEM showed apparent deposition of metal granules near the cell wall and vacuole as adoption features of plants. But the variable concentration of metal accumulation in different parts by various plants indicated the variable potential of tested plants with various metals. This also indicated their metal bio-availability and movement to plant tissue. Further, their bioconcentration factor (BCF) and translocation factor (TF) > 1.0 indicated the hyperaccumulation tendency of plants Mn was accumulated maximum in leaves C. album (69.38 mg/kg−1) followed by Cu (25.75 mg/kg −1), As (23.20 mg/kg −1), Fe (20.90 mg/kg −1) and Pb was maximum accumulated (22.41 mg/kg −1) in R. cummunis leaves. The result revealed that arsenic has been accumulated in higher amount root, shoot and leaves of all tested plants. The metal accumulator plants showed phytoremediation potential also by reducing various pollution parameters after growth on sludge. These potential plants may be used as biotechnological tools for the eco-restoration of polluted sites.

Drought stress adversely impacts growth, crop production, reproductive organ development, and yield characteristics in maize. As a drought-sensitive crop, maize ( Zea mays L.) shows considerable varietal differences. A study was conducted at the Tissue Culture Laboratory, Department of Biology, Faculty of Mathematics and Natural Sciences, University of North Sumatra, Medan, Indonesia in order to identify drought-tolerant maize varieties. During germination and early seedling growth, 16 local accessions were evaluated for drought tolerance. Based on local climate and soil conditions, these specific accessions were chosen. The varieties were tested against five levels of drought stress imposed by Polyethylene glycol 6000 (PEG-6000) at 10, 20, 30, 40, and 50%. An experiment with three replications was conducted using a completely randomized design. In the study, local maize accessions (BI3, SB5, DS2, and MN3) and the hybrid variety (H) showed the capability of tolerating drought stress. Generally, germination time, germination percent and vigor index, root and shoot length, shoot ratio, and fresh and dry weight were decreased by increasing PEG concentrations (up to 50%). According to ANOVA results, shoot water content was not significantly affected by the PEG, nor was the interaction between the PEG and the accessions. The root water content, however, was significantly affected by PEG, and the interaction between PEG and accessions. Although interactions between accessions with low PEG concentrations improved germination characteristics, the root histology of the accessions varied. According to drought tolerance indexes, five maize accessions are drought-tolerant, including H (0.683), SB5 (0.617), DS2 (0.565), MN3 (0.512), and BI3 (0.504). The drought-tolerant varieties are recommended in regions with low rainfall or low water sources since they are less water-intensive and produce higher yields., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

The article presents a study which compares the biochemical, cytological, and histological effects of cyanobacterial toxins cylindrospermopsin (CYN) and microcystin-LR (MCY-LR) in white mustard seedlings. It states that zone of lateral root formation and apical meristems of main roots were used for cytological analysis. Results show that both CYN and MCY-LR inhibited the full lateral roots development formation.

Abstract: Rye (Secale cereale L.) plants have high tolerance to Al, and become unique tools to study Al-toxicity and tolerance mechanisms. To better understand if and how Al-induced root growth inhibition is related with root histological differentiation, nutrient balances and cell cycle dynamics, tolerant (AT6) and sensitive (AS6) rye lines were exposed for 24h to 1.1mM Al. After that period, half of plants were transferred to medium without Al, while the other group was maintained with Al for more 48h. AS6 plants showed evident and irreversible root growth inhibition, decreases in water content, organic matter and carbohydrate reserves. Also, roots of this line showed greater increases in Ca levels and changes in anatomy (e.g. thickness). Data revealed that AS6 plants accumulate more Al in roots and leaves, suggesting more Al translocation to the shoots. The two lines responded differently to Al exposure in what concerns endodermis differentiation and cell cycle profile. The tolerant line shows a tendency to arrest in G0/G1 phase whereas the sensitive have a tendency to arrest in S phase. These data point to an arrest of cells in specific cell cycle phases, leading to eventual Al-induced cell cycle delay. Taken all together, data show that even short-term exposure to Al leads to root anatomical modifications that in combination with the cell cycle dynamic changes, may represent a plant strategy to cope with this stress. [Copyright &y& Elsevier]

In Chile, avocado (Persea americana Mill.) orchards are often located in poorly drained, low-oxygen soils, situation which limits fruit production and quality. The objective of this study was to evaluate the effect of injecting soil with hydrogen peroxide (H202) as a source of molecular oxygen, on plant water status, net CO2 assimilation, biomass and anatomy of avocado trees set in clay loam soil with water content maintained at field capacity. Three-year-old 'Hass' avocado trees were planted outdoors in containers filled with heavy loam clay soil with moisture content sustained at field capacity. Plants were divided into two treatments, (a) H202 injected into the soil through subsurface drip irrigation and (b) soil with no H202 added (control). Stem and root vascular anatomical characteristics were determined for plants in each treatment in addition to physical soil characteristics, net CO2 assimilation (A), transpiration (T), stomatal conductance (gs), stem water potential (SWP), shoot and root biomass, water use efficiency (plant bioniass per water applied [WUEb]). Injecting H202 into the soil significantly increased the biomass of the aerial portions of the plant and WUEb, but had no significant effect on measured A, T, gs, or SWP. Xylem vessel diameter and xylem! phloem ratio tended to be greater for trees in soil injected with H2O2 than for controls. The increased biomass of the aerial portions of plants in treated soil indicates that injecting H202 into heavy loam clay soils may be a useful management tool in poorly aerated soil. [ABSTRACT FROM AUTHOR]

The present manuscript has focused on the heavy metal; accumulation potential by common native plants i.e. Chenopodium album L., Ricinus communis, Ranunculus sceleratus , and Rumex dentatus growing on the disposed of pulp and paper mill effluent sludge. The sludge showed the abundance of benzene propanoic acid tert- butyldimethylsilyl ester, Octadecanoic acid, TMS, Hexadecanoic acid, TMS, cinnamic acid-α-phenyl-TMS ester, β-sitosterol TMS, 4-mercaptobenzoic acid as residual complex organic compounds along with heavy metals Fe (98.30 mg/L -1 ), Zn (51.00 mg/L -1 ), Cu (3.21 mg/L -1 ), Cd (9.11 mg/L -1 ), Mn (18.27 mg/L -1 ), Ni (5.21 mg/L -1 ), (Hg 0.014 mg/L -1 ) which were above the prescribed limit of environmental standard. The complexation of organic compounds with heavy metal restricts the bioavailability of metals to plants. But the metal analysis in various parts of the plant showed a significant amount of metal accumulation. Further, histological observations of root tissue through TEM showed apparent deposition of metal granules near the cell wall and vacuole as adoption features of plants. But the variable concentration of metal accumulation in different parts by various plants indicated the variable potential of tested plants with various metals. This also indicated their metal bio-availability and movement to plant tissue. Further, their bioconcentration factor (BCF) and translocation factor (TF) > 1.0 indicated the hyperaccumulation tendency of plants Mn was accumulated maximum in leaves C. album (69.38 mg/kg -1 ) followed by Cu (25.75 mg/kg -1 ), As (23.20 mg/kg -1 ), Fe (20.90 mg/kg -1 ) and Pb was maximum accumulated (22.41 mg/kg -1 ) in R. cummunis leaves. The result revealed that arsenic has been accumulated in higher amount root, shoot and leaves of all tested plants. The metal accumulator plants showed phytoremediation potential also by reducing various pollution parameters after growth on sludge. These potential plants may be used as biotechnological tools for the eco-restoration of polluted sites., (© 2020 Published by Elsevier Ltd.)