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The rise in temperature during autumn is one of the most serious negative factors for winter rye (Secale cereale L.), which leads to wilting, plant damage by fungal diseases and yield losses. The a...

Barnyardgrass (Echinochloa spp.) is the most common noxious weed in rice paddies as it inhibits rice growth and reduces grain yield. To date, little information is available on above- and belowground-growth changes in rice due to neighboring barnyardgrass. This study aimed to investigate the changes in root traits and shoot growth of rice when it is grown with different kinds of barnyardgrass. Japonica rice plants (var. Nanjing 9108) were co-cultured with two varieties of Echinochloa crusgalli (L.) Beauv. (EP, var. mitis (pursh) Petern; EH, var. zelayensis (H.B.K.) Hitchc), and E. colonum (L.) Link (EL) in the field in 2017 and 2018. Four treatments included control (i.e., weed free rice plants) and co-cultures with each of three barnyardgrasses (EP, EH, and EL). The results revealed that EP, EH, and EL treatments significantly reduced rice grain yields by 30.6%–36.2%, 42.5%–46.5%, and 10.6%–14.3%, respectively. Shoot growth including shoot dry weight, leaf photosynthetic rate, zeatin (Z) and zeatin riboside (ZR) in grains, and activities of key enzymes involved in sucrose-to-starch conversion in grains and root traits, such as length density, root dry weight, total absorbing surface area, active absorption surface area, oxidation activity, and Z + ZR contents in roots were dramatically reduced during post-heading stages of rice when grown with the three kinds of barnyardgrass. Moreover, above-mentioned rice shoot growth indices were strongly and positively correlated with root traits. These results suggested the decrease in rice shoot growth and root traits during post-heading stages contributes to the reduction in the rice yield when it grows with barnyardgrass neighbors.

lbgBackground and Objective:l/bg The cat whiskers plant (ligOrthosiphon aristatusl/ig Blume Miq) is a plant that has been widely used as raw material for traditional medicine. The population of white-purple varieties of ligO. aristatusl/ig is decreasing efforts to maintain the white-purple ligO. aristatusl/ig need to be done keeping in mind its potential as raw material for traditional medicine. This study aims to determine the composition of a suitable medium in growing plantlet ligO. aristatusl/ig white-purple varieties and the content of its secondary metabolites. lbgMaterials and Methods:l/bg The internode explants were induced on MS medium added by various combinations of zeatin and 2,4-Dichlorophenoxyacetic acid (2,4-D). Root induction was carried out on shoots formed on MS medium with Indole-3-Butyric Acid (IBA). The acclimatization process was carried out using soil media. Determination of secondary metabolite levels was carried out on ligO. aristatusl/ig (ligin vitrol/ig culture) and wild-type plants aged ten months using high-performance liquid chromatography (HPLC). lbgResults:l/bg MS+BAP 2ppm+NAA3 ppm media was the optimal medium for growing shoots in leaf explants. Media MS+zeatin 3 ppm+2,4-D 2 ppm produced good shoot growth on internode explants. The best root induction occurred in MS+IBA media of 0.75 ppm. The acclimatization process was successful on shoots originating from the internode, while those from leaf explants had not succeeded in growing and developing. lbgConclusion:l/bg The levels of rosmarinic acid and sinensetin in the white-purple variety ligO. aristatusl/ig (ligin vitrol/ig culture) were 1.08 and 1.62% w/w and higher than those of wild varieties.

Adventitious rooting of walnut species (Juglans L.) is known to be rather difficult, especially for mature trees. The adventitious root formation (ARF) capacities of mature trees can be significantly improved by rejuvenation. However, the underlying gene regulatory networks (GRNs) of rejuvenation remain largely unknown. To characterize such regulatory networks, we carried out the transcriptomic study using RNA samples of the cambia and peripheral tissues on the bottom of rejuvenated and mature walnut (Juglans hindsii × J. regia) cuttings during the ARF. The RNA sequencing data suggested that zeatin biosynthesis, energy metabolism and substance metabolism were activated by rejuvenation, whereas photosynthesis, fatty acid biosynthesis and the synthesis pathways for secondary metabolites were inhibited. The inter- and intra-module GRNs were constructed using differentially expressed genes. We identified 35 hub genes involved in five modules associated with ARF. Among these hub genes, particularly, beta-glucosidase-like (BGLs) family members involved in auxin metabolism were overexpressed at the early stage of the ARF. Furthermore, BGL12 from the cuttings of Juglans was overexpressed in Populus alba × P. glandulosa. Accelerated ARF and increased number of ARs were observed in the transgenic poplars. These results provide a high-resolution atlas of gene activity during ARF and help to uncover the regulatory modules associated with the ARF promoted by rejuvenation.

Citrus holds the key position in horticulture sector of Pakistan in terms of area and production. Kinnow is considered as the trademark of Pakistan’s citriculture industry. Cultivation experiment was conducted to evaluate the endogenous plant hormones, leaf gas exchange, photosynthetic pigments, vegetative performance, and yield of Kinnow mandarin grafted on nine rootstocks (Rough lemon, cox mandarin, Fraser hybrid, Troyer citrange, Cleopatra mandarin, Poncirus trifoliata, Benton, C-35, and Carrizo citrange). Maximum indole acetic acid (IAA), gibberellic acid (GA3), and zeatin (ZT) levels were recorded in scion and rootstock of Poncirus trifoliata followed by Fraser hybrid. Troyer citrange rootstock depicted maximum amount of abscisic acid in scion and rootstock. Maximum leaf gas exchange in Kinnow mandarin was recorded on Fraser hybrid rootstock. Kinnow grafted on Troyer citrange rootstock had minimum stomatal conductance and photosynthetic activity because of high ABA level. Photosynthetic pigments of Kinnow mandarin were maximum on Poncirus trifoliata and minimum on Troyer citrange. A positive correlation was observed among the levels of IAA, GA, ZT, and vegetative growth of Kinnow mandarin. It is concluded that endogenous hormones modulated the growth of Kinnow mandarin. Poncirus trifoliata and Fraser hybrid rootstocks could be an alternate rootstocks of traditional Rough lemon for Kinnow mandarin.

Blueberry (Vaccinium spp. L.) plants exhibit high potential of regeneration via adventitious shoot formation on a semi-solid medium followed by shoot elongation in a liquid medium under bioreactor systems. To find out whether DNA methylation plays a role during shoot elongation, we compared DNA methylation level in the regenerants of two in vitro-grown half-high blueberry (V. corymbosum L. × V. angustifolium Ait.) cultivars Patriot and Chippewa on a semi-solid medium (SSM) in glass bottles and in a liquid medium in temporary immersion bioreactors (TIB), via methylation-sensitive amplification polymorphism (MSAP) technique. The SSM was separately fortified with various combinations of two plant growth regulators, zeatin and thidiazuron for shoot regeneration but elongation was carried out using the same medium under both SSM and TIB systems with only zeatin. Zeatin at 9.2 µM produced the maximum shoots in SSM and TIB for both cultivars, which varied from 30 to 33 in SSM and from 28 to 29 in TIB for Patriot and Chippewa, respectively. However, shoots proliferated in TIB were more vigorous. Noticeable changes in the methylation profiles were detected using MSAP in the regenerants grown in each type of culture system. The TIB system exhibited a significant increase in total methylation percentage (47–50%) in comparison to SSM (25–32%) in both cultivars. Similarly, the plants regenerated from TIB system were more polymorphic than those from SSM system. We describe here the effects of culture in vitro on DNA methylation that induced during the process of shoot elongation in two half-high blueberry cultivars. In vitro shoot culture was achieved in half-high blueberry cultivars using a semi-solid and a liquid medium; plantlets developed from liquid medium showed higher level of DNA methylation alterations.

This study evaluated the effect of the addition of biomass and aqueous extract of the green microalga Desmodesmus subspicatus on asymbiotic germination and seedling development in the orchid Cattleya warneri. Seeds were germinated in MS culture medium with the macronutrients reduced by half (MSM/2), supplemented with 0, 0.25, 0.5, 1.0, and 2.0 g L−1 of microalgal biomass or its aqueous extract. Chlorophyllous protocorms were observed at 4 weeks and the addition of biomass or extract (0.25 g L−1) accelerated germination. Twenty-four weeks after sowing high percentages of seedlings (greater than 95%) were observed in all treatments with biomass, as well as with the addition of 0.25 or 0.5 g L−1 of microalgal extract. Shoot elongation and root development were increased in the semi-solid medium supplemented with 2.0 g L−1 of activated charcoal. Plantlets cultivated in a double-phase medium (a thin layer of liquid medium, containing 0.5 to 2 g L−1 of extract on the semi-solid medium) demonstrated the positive effect of zeatin on the formation of new shoots and plants. Plantlets were successfully acclimatized, showing high percentages of survival (over 80%) with foliar sprays of 2.0 g L−1 of biomass or 1.0 g L−1 extract for 4 months. The addition of D. subspicatus biomass or extract accelerated germination, induced shoot formation, and produced well-developed seedlings during acclimatization. A complete and efficient protocol of germination and seedling development of C. warneri was therefore achieved using biomass and aqueous extract of D. subspicatus.

Cross-talk between phytohormones and sugars is intensely involved in plant metabolism, growth and regeneration. We documented alterations in cytokinin (CK) homeostasis in four developmental stages during de novo shoot organogenesis (DNSO) of kohlrabi (Brassica oleracea var. gongylodes cv. Vienna Purple) seedlings induced by exogenous CKs, trans-zeatin (transZ) and thidiazuron (TDZ), added together with elevated sucrose concentration (6% and 9%). Significant impact of CK and sucrose treatment and their interaction was recorded in all investigated stages, including plantlet development before calli formation (T1 and T2), calli formation (T3) and shoot regeneration (T4). Results showed remarkable increase in total CK levels for transZ treatment, particularly with 9% sucrose. This trend was observed for all physiological and structural groups of CKs. Application of TDZ contributed to little or no increase in CK levels regardless of sucrose concentration. Analysis of expression profiles of organogenesis-related genes involved in auxin transport, CK response, shoot apical meristem formation and cell division revealed that higher sugar concentration significantly downregulated the analysed genes, particularly in T3. This continued on TDZ, but transZ induced an opposite effect with 9% sucrose in T4, increasing gene activity. Our results demonstrated that phytohormone metabolism might be triggered by sucrose signalling in kohlrabi DNSO.

Ninebark is a very popular ornamental shrub. Micropropagation is an efficient method for mass production of uniform plant material. This study was designed to develop and optimize conditions at all phases of ninebark micropropagation. For the multiplication stage, the Murashige and Skoog (MS) medium at full concentration and pH 5.8 was chosen as the basal medium. Sorbitol proved a more effective carbohydrate source than fructose, with no adverse effects on shoot vitrification or the medium itself. The best shoot production, both in number and length, was on the medium enriched with 2 and 3 mg·L−1 zeatin. High numbers of shoots were also obtained in treatments with 1 mg·L−1 6-benzyladenine (BA) or 2 mg·L−1 meta-Topolin (mT) in the basal medium. BA was the most cost-effective cytokinin. There was a positive effect of the gibberellic acid on proliferation: the highest shoot number per explant was produced in the presence of 1 mg·L−1 GA3. No effect of the culture age (up to 20 subcultures) on the percentage of regenerating explants was evident, and the highest numbers of shoots were obtained between passages 10 and 17. For rooting, the MS medium at half strength was used. The best rooting was at 1 mg·L−1 IBA. Spraying the in vitro rooted cuttings with abscisic acid (ABA) favored plant acclimation to the ex vitro conditions. Exvitro rooting, including the treatments with IBA and ABA, shortened the production time by approximately one third.

Patchouli is one of the essential oil-producing plants which is commonly found in Indonesia, but the productivity tends to decline. Tissue culture technology is one alternative to increase patchouli plant productivity. Tissue culture requires growth regulators in order for the plants to grow optimally. Moringa plants have the potential as a source of growth regulators for tissue culture because Moringa leaves contain the zeatin hormone. Therefore, a comparison test of various concentrations of the zeatin and the moringa leaf extract is needed to determine whether the Moringa leaf extract can be an alternative to the zeatin hormone. This study aimed to investigate the effect of Moringa leaf extract on the growth of patchouli bud explants. The study employed a complete random design (CRD) with the treatment of concentrations of Moringa leaf extract in MS media. Moringa leaf extract was given at 30 grams/L, 40 grams/L, and 50 grams/L, respectively. Meanwhile, the zeatin hormone was given at a concentration of 1.5 ppm, 2 ppm, and 2.5 ppm. Each treatment was repeated four times. Moringa leaves were extracted by maceration method, and patchouli explants were obtained from the 3rd sub-culture of patchouli shoots. From the research results, it can be concluded that (1) the use of Moringa leaf extract can improve the growth of patchouli explants, and (2) the use of 40 grams/L of Moringa leaf extract can be an alternative to substitute the use of 1.5 ppm zeatin hormone.

Zizania latifolia is a perennial aquatic vegetable, whose symbiosis with the fungus Ustilago esculenta (member of Basidiomycota, class Ustilaginaceae) results in the establishment of swollen gall formations. Here, we analyzed symbiotic relations of Z. latifolia and U. esculenta, using a triadimefon (TDF) treatment and transcriptome sequencing (RNA-seq). Specifically, accurately identify the whole growth cycle of Z. latifolia. Microstructure observations showed that the presence of U. esculenta could be clearly observed after gall formation but was absent after the TDF treatment. A total of 17,541 differentially expressed genes (DEGs) were identified, based on the transcriptome. According to gene ontology term and Kyoto Encyclopedia of Genes and Genomes pathway results, plant hormone signal transduction, and cell wall–loosening factors were all significantly enriched due to U. esculenta infecting Z. latifolia; relative expression levels of hormone-related genes were identified, of which downregulation of indole 3-acetic acid (IAA)-related DEGs was most pronounced in JB_D versus JB_B. The ultra–high performance liquid chromatography analysis revealed that IAA, zeatin+trans zeatin riboside, and gibberellin 3 were increased under U. esculenta infection. Based on our results, we proposed a hormone–cell wall loosening model to study the symbiotic mechanism of gall formation after U. esculenta infects Z. latifolia. Our study thus provides a new perspective for studying the physiological and molecular mechanisms of U. esculenta infection of Z. latifolia causing swollen gall formations as well as a theoretical basis for enhancing future yields of cultivated Z. latifolia. [Formula: see text] The author(s) have dedicated the work to the public domain under the Creative Commons CC0 “No Rights Reserved” license by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law. 2021

This study aimed to determine the ability of microorganisms originating from the root ecosystem (Rhizosphere) of cocoa (Theobroma cacao L) as a potential superior to biological agents. For the experiment, soil samples were observed from the rhizosphere of cocoa plants in Pandeglang Regency. At this stage, the research was focused on finding out the extent of microbe screening results from cocoa rhizosphere soil in producing phytohormones. The results from the initial selection showed a population of Azotobacter 2.8 x 105 cfu/mL, a population of Azospirillium of 0.3 x 102 cfu/mL, and a population of Phosphate-solubilizing bacteria (PSB) 4.1 x 107 cfu/mL. In the hemolysis test conducted for 9 isolates, only 1 isolate showed a negative result. From the test of the ability to produce phytohormones showed respectively from the highest values were IAA 5.467 mg/L, gibberellin 3.768 mg/L, zeatin 1.321 mg/L, and kinetin 0.886 mg/L. The land rhizosphere of Pandeglang cocoa plant had superior potential microbes which could be used as biological fertilizers.

The aim of the present research work was the screening of the effect of the main cytokinin (BAP, kinetin or zeatin) in different concentrations and combinations with the auxin NAA on androgenesis of white cabbage anthers cultivated in vitro. The results obtained are regarded as an intermediary stage for the development of a reproducible protocol for in vitro regeneration of plant from anther culture. Thus, for the determination of the influence of plant growth regulators formula over the callus induction and plant regeneration from anthers cultivated in vitro in the present study the authors undergo a screening of the three most frequently utilized cytokinins (BAP, kinetin and zeatin) in different concentration and combination with the auxin NAA. The results obtained, indicated that the best morphogenetic reaction is obtained on variant with BAP as the main growth regulator.

The effects of changes in auxin transport in response to different osmotic potentials (Ψo) were analyzed in the roots and leaves of two leguminous species with different degrees of salt tolerance: the halophyte Prosopis strombulifera (Lam.) Benth. and the glycophyte Glycine max L. The potentials were generated with sodium chloride (NaCl), sodium sulfate (Na2SO4), and the iso-osmotic mixture of both salts (NaCl + Na2SO4). The values evaluated were −1, −1.8, and −2.6 MPa for P. strombulifera, and −0.47, −0.69, and −0.87 MPa for G. max. In addition, the plants were sprayed with 2,3,5-triiodobenzoic acid (TIBA), an auxin transport inhibitor. The parameters measured included root length, shoot height, number of leaves, relative membrane permeability in roots, and endogenous levels of abscisic acid (ABA), indole-3-acetic acid (IAA), and zeatin (Z). Significant responses were observed at the lowest potentials evaluated (−2.6 MPa for P. strombulifera and −0.89 MPa for G. max). Treatment with Na2SO4 inhibited plant growth more than the others, increased the relative membrane permeability, and enhanced ABA production to its highest levels. These toxic effects were slightly reversed in the presence of iso-osmotic mixture. TIBA brought about impaired development in shoots and roots, the highest values for membrane permeability, alterations in the distribution of endogenous ABA, IAA, and Z, as well as harmful effects on the growth response of both species. In general, the alterations in auxin transport intensified the effects of salinity, which confirms the essential role of this mechanism in plants under salt stress or in normal, non-stressful conditions.

Signal perception in plants is determinant to trigger specific physiological changes that confer resistance during the early stages of the insect attack. Thus, molecular characterization of both insect effectors and plant hormonal regulators are essential in developing forage grasses resistant to infestation by spittlebug Mahanarva spectabilis. We evaluated the presence of effectors in the salivary glands of M. spectabilis that could enable the infestation of elephant grass (Pennisetum purpureum). The presence of an NTPDase-like enzyme was confirmed, and higher activity was observed in females that hydrolyzed ADP. High levels of long chain fatty acids, such as octadecanoid acid (19.5%), prostaglandin A2 (4.7%), eicosanoid acid and the phytohormone salicylic acid (~4.0 μg/g) were also detected in the salivary glands. After 24 h of infestation, the phytohormone profiles were altered in leaves damaged by M. spectabilis, suggesting that the insect effectors modulate the plant response. Our results suggest that the plant response modulation may be the result of crosstalk between the salicylic acid, jasmonic acid, abscisic acid and zeatin pathways, induced by molecules from the salivary glands. This shows that the spittlebugs can interfere with jasmonic acid and zeatin accumulation in elephant grass plants.

The aim of this study was to evaluate the effect of two green microalgae (Messastrum gracile and Chlorella vulgaris) in comparison with plant growth regulators (6-benzylaminopurine, BAP; thidiazuron, TDZ; zeatin, ZEA) on the in vitro propagation of Cattleya labiata, an endangered orchid, using the thin cell layer (TCL) technique from protocorms. TCL sections were cultivated in MS/2 medium containing M. gracile extract (EM) and biomass (BM); C. vulgaris extract (EC) and biomass (BC); and BAP, TDZ, and ZEA in different concentrations. Subsequently, the explants were grown in MS/2 medium, with 2 g L−1 of activated charcoal, to induce elongation and roots formation. For acclimatization, plants were transplanted in trays using Sphagnum sp. as substrate. TCL explants showed a higher formation of protocorm-like bodies (PLBs) than entire protocorms. Explants cultivated in media supplemented with BM showed a high rate of PLB regeneration (59%) and high mean number of PLBs (4 per explant) and 85% survival after acclimatization of the plants. Supplementation with BAP stimulated similar morphogenic responses to those observed with BM and superior results obtained with ZEA and TDZ. Mass propagation of C. labiata plants was successfully achieved using TCL, and it is recommended to supplement the MS/2 medium with 4 g L−1 of BM or 4 mg L−1 of BAP. Microalgae extracts and biomasses are effective alternatives for in vitro propagation of C. labiata that can replace plant growth regulators, as they favored the formation of PLBs and plants.

The salinity stress tolerance in plants has been studied enormously, reflecting its agronomic relevance. Despite the extensive research, limited success has been achieved in relation to the plant tolerance mechanism. The beneficial interaction between Piriformospora indica and rice could essentially improve the performance of the plant during salt stress. In this study, the transcriptomic data between P. indica treated and untreated rice roots were compared under control and salt stress conditions. Overall, 661 salt-responsive differentially expressed genes (DEGs) were detected with 161 up- and 500 down-regulated genes in all comparison groups. Gene ontology analyses indicated the DEGs were mainly enriched in "auxin-activated signaling pathway", "water channel activity", "integral component of plasma membrane", "stress responses", and "metabolic processes". Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that the DEGs were primarily related to "Zeatin biosynthesis", "Fatty acid elongation", "Carotenoid biosynthesis", and "Biosynthesis of secondary metabolites". Particularly, genes related to cell wall modifying enzymes (e.g. invertase/pectin methylesterase inhibitor protein and arabinogalactans), phytohormones (e.g. Auxin-responsive Aux/IAA gene family, ent-kaurene synthase, and 12-oxophytodienoate reductase) and receptor-like kinases (e.g. AGC kinase and receptor protein kinase) were induced in P. indica colonized rice under salt stress condition. The differential expression of these genes implies that the coordination between hormonal crosstalk, signaling, and cell wall dynamics contributes to the higher growth and tolerance in P. indica-inoculated rice. Our results offer a valuable resource for future functional studies on salt-responsive genes that should improve the resilience and adaptation of rice against salt stress.

Bio-organic–chemical fertilizer (BCF) has great potential to enhance agricultural production, protect environment, and improve sustainability. However, current BCFs are used only in a limited scope mainly due to the low activity of beneficial bacteria. It is significant to develop new BCFs with high beneficial bacteria activity for sustainable agricultural production. In this study, a novel slow-release bio-organic–chemical fertilizer (SBCF) was prepared from activated lignite, bacillus AMCC100153 (B153) (beneficial bacteria for tomato), and slow-release fertilizer (CSF) with suitable pH and low dissolubility salt content (to protect the bacterial activity). The pH and EC of different types of SBCFs with different compositions were determined and compared with those of BCFs derived from common chemical fertilizers (BCCF). The B153 activities were measured and compared with the optimum formula of SBCF. The bacillus colonization rules of SBCF and BCCF in tomato pot soil were explored by the Real-time qPCR. SBCF had higher bacillus activity than the corresponding BCCF. Pot experiments also showed that the bacillus formed colonization rapidly on tomato roots and secreted substances to promote root growth. The HPLC analysis found that the promoting substances were auxin and zeatin. Compared with no fertilizer control (CK) and the BCCF treatments, the SBCF treatment increased tomato yields by 73.08% and 29.04%, respectively. Findings of this work suggest that SBCF with high biological activity and growth promoting effect has great potential in agriculture production system in the future.

Flowering is an important process for the reproduction of higher plants. Up to this point, the studies on flowering have mostly focused on the model plant Arabidopsis thaliana, and the flowering mechanism of fruit trees remains mostly unknown. The diversity of the flowering time of loquat (Eriobotrya japonica Lindl.) makes it an ideal material to study the regulation of flowering. In this study, we first observed the inflorescence bud differentiation in two varieties of loquat that had different blooming times (cv. Dawuxing (E. japonica), that blooms in the fall and cv. Chunhua (E. japonica×Eriobotrya bengalensis Hook. f.) that blooms in the spring) and found that the starting time of inflorescence bud differentiation and the speed of inflorescence development were responsible for the difference in blooming times. The determination of endogenous phytohormones by high performance liquid chromatography (HPLC) indicated that abscisic acid (ABA), zeatin (ZT), and gibberellin (GA3) promoted flowering in loquat, while indole-3-acetic acid (IAA) was mainly involved in inflorescence bud differentiation in Chunhua. A transcription level analysis illustrated that multiple flowering-related genes could respond to different signals, integrate to the TFL1, AP1 and FT genes, and then synergistically regulate flowering in loquat. Thus, this study provides a new insight into flowering regulation mechanisms in loquat.

Moringa oleifera Lam., (family: Moringaceae) has begun to gain more popularity as a new ‘superfood’ due to its high nutritive value. It has been used for generations to treat and prevent the diseases such as diabetes, anemia, arthritis, and respiratory, skin, heart, liver and digestive disorders. Apart from these pharmacological activities, it is also a plant growth enhancer. The present work deals with a comparative assessment of the effect of foliar spray of Moringa leaf extracts (MLEs) of different varieties (PKM-1, PKM-2, Jaffna, ODC and Conventional) on the stevioside and mineral contents of Stevia rebaudiana Bertoni, a commercial natural sweetener plant. The decreasing order of stevioside and zeatin content in stevia plants after MLEs foliar spray, as determined by High Performance Liquid Chromatography (HPLC) was: Jaffna (7.73%; 0.0063%) > PKM-1 (6.93%; 0.0056%) > PKM-2 (6.45%; 0.0051%) > ODC (4.14%; 0.0048%) > Conventional (3.86%; 0.0042%) > Control (2.94%; 0.00088%) respectively. While, the decreasing order of mineral contents as determined by flame photometer was: Jaffna > PKM-1> PKM-2 > ODC > Conventional > Control. The comparative study revealed that among all the varieties, Jaffna significantly improved the growth and physiochemical parameters of stevia plants. Thus, this variety can be used as an eco-friendly and cost-effective plant growth enhancer in stevia farming and can be used for other commercially important crops.

Clarifying the characteristics of photoassimilates transport and distribution to the fruits from leaves located on different branches can guide the branch composition and pruning of apple trees. A field experiment was carried out in 6-year-old ‘Fuji’3/M26/Malus hupehensis Rehd. apple trees, and the 13C-labeled tracer method was used to study the growth characteristics of the leaves on different branches (vegetative branches, long branches, mid branches, short branches, bourse branches, and cluster branches) and the translocation of 13C-photoassimilates to the fruit from these leaves at the fruit enlargement stage in 2018 and 2019. Additionally, the effect of the distance between the leaf and fruit (leaves from both short and long branches that were 20, 40, and 60 cm away from the fruit) was assessed. We found that with increased branch length, the intensity of photosynthesis and the level of photoassimilates synthesis in the leaves decreased, but increased in the leaves near the fruits. Indole-3-acetic acid, gibberellic acid, and zeatin accumulated in the leaves of the longer branches, while abscisic acid accumulated in the leaves of the shorter branches. The δ values of the 13C-labeled leaves from the short branches, the short branches 20 cm away from the fruits (S20), and the bourse branches at the fruit stage were low, and the corresponding δ values of the fruits were high. The 13C absorption of the fruit was highest in the leaves of the short branches, followed by those of the bourse branches, S20, and mid branches, and was lower in the leaves of the vegetative branches, cluster branches, and 60 cm short and long branches. The leaf 13C-photoassimilates in the short branches were more greatly transported to the fruits than those from the long branches when the distance between the leaves and fruits was the same. The 13C absorption of the fruit increased by 10.91, 5.28, and 1.14 mg at the leaf–fruit spacing of 20, 40 and 60 cm, respectively, and the leaf–fruit spacing was determined to be more important than branch type in determining the 13C absorption of the fruit.

We developed an efficient regeneration system through indirect somatic embryogenesis for Melia azedarach L. Different culture media with various plant growth regulator (PGR) combinations were evaluated. It was found that callus induction, proliferation and morphology depend strongly on the PGR combination of the culture medium. In fact, the callus induction rate varied from 7 to 100%. The highest callogenesis rate was observed on half-strength Murashige and Skoog (MS/2) medium supplemented with 3 mg/L 1-naphthalene acetic acid (NAA), 1 mg/L zeatin and 5 mg/L gibberellic acid (GA3). Calli were either white and friable, light brown and hydrated or brown and compact, with different proliferation potential. Somatic embryo formation was observed either directly on the explant or on the previously induced calli, depending on the PGR combination of the induction medium. The highest somatic embryogenesis rate was 29% in the calli induced on MS/2 medium supplemented with 3 mg/L NAA, 1 mg/L 6-benzylaminopurine (BAP) and 5 mg/L GA3. Callus induced on MS/2 medium containing 3 mg/L indole-3-butyric acid (IBA), 1 mg/L BAP and 5 mg/L GA3 showed a somatic embryogenesis rate of 5% while a similar rate was observed on the explants cultured on MS/2 medium containing 3 mg/L NAA, 1 mg/L zeatin and 5 mg/L GA3. However, in this latter case, somatic embryos were formed directly on the explant. After transferring somatic embryos to the germination medium, the germination rate was 51.28%. All germinated embryos were successfully converted into complete plantlets and showed normal growth and development.

Populus euphratica Oliv., the Euphrates poplar, is the tallest tree species in the arid desert areas of Northwest China. Investigation of its drought-resistance genes is valuable to increase understanding of drought resistance mechanisms. RNA-seq of leaves and roots under drought simulation by 25% polyethylene glycol-6000 (PEG 6000) were performed at 0, 4, and 12 h. Leaves and roots responded differently to drought via differentially upregulated and downregulated genes; more genes were downregulated than upregulated in both leaves and roots. Additionally, these differentially expressed genes were enriched in different GO terms and KEGG pathways. For example, GO term ‘response to organic substance’ and KEGG pathway ‘nitrogen metabolism’ were enriched for drought-stressed leaves, while GO term ‘cell wall organization or biogenesis’ and KEGG pathway ‘zeatin biosynthesis’ were enriched for drought-stressed roots. The enrichment of the GO term ‘enzyme linked receptor protein signalling pathway’ in both leaf and root drought responses suggests that these tissues may also have similar mechanisms. However, roots under drought stress for four hs responded by activating programed cell death. The KEGG pathway ‘plant hormone signal transduction’ was detected for 4- and 12-h drought-stressed leaves and 12-h drought-stressed roots, suggesting that plant hormone signal transduction plays an important role in both roots and leaves. GO enrichment of upregulated and downregulated genes for leaves and roots reflect differentially regulatory mechanisms of response to drought stress via different biological processes such as the regulation of photosynthesis and auxin signalling pathway in leaves, and the regulation of defence response and water homeostasis in roots. Fifteen candidate genes, including transcription factors, protein kinase, transporter, late embryogenesis abundant protein and mannitol dehydrogenase, were further selected to determine their response to drought using qRT-PCR. The results show that the expression patterns of 13 of the 15 genes correspond to the RNA-seq results. This study provides new insights into the drought response mechanism of P. euphratica and suggests new candidate gene resources.

Seed priming is a promising approach to improve germination, emergence, and seedling growth by triggering pre-germinative metabolism and enhancing seedling vigor. Recently, nanopriming gained importance in seed improvement as a result of the small size and unique physicochemical characteristics of nanomaterials. In the present study, silver and gold nanoparticles were synthesized using onion extracts as the reducing agent. Similarly, the agro-food industrial byproducts citrus seed oil and curcumin-removed turmeric oleoresin were used for the preparation of nanoemulsions. For seed priming, these green-synthesized nanomaterials were incubated with seeds of two onion (Allium cepa L.) cultivars (Legend and 50147) for 72 h, and then the plants were grown in a greenhouse for 3 weeks. Seed priming with these nanomaterials increased seed germination and seedling emergence. One-dimensional 1H nuclear magnetic resonance and liquid chromatography coupled with mass spectrometry metabolomics studies showed that different nanopriming treatments distinctly altered the metabolome of onion seedlings. Seed priming treatments significantly inhibited plant hormones and growth regulators, such as abscisic acid and cis-(+)-12-oxo-phytodienoic acid, and enhanced germination stimulators, such as γ-aminobutyric acid and zeatin, in onion seeds and seedlings. Therefore, these priming treatments have positive impact on improving seed performance and plant growth.

In this study, genetic engineering methods, ranging from gene transformation to gene editing, were efficiently conducted on cotyledon explants in Solanum nigrum. Organogenic calli were observed on the explants following 10 days of growth on medium supplemented with 2 mg/L zeatin and 0.2 mg/L indole acetic acid (IAA), which we suggest to be an efficient shoot initiation medium (SM1). In vitro shoot production was enhanced in explants grown on media supplemented with 1 mg/L zeatin and 0.1 mg/L IAA, which we used as a proper shoot differentiation medium (SM2) in S. nigrum shoot regeneration. Direct infection of explants with Agrobacterium harboring CRISPR/Cas9 constructs can simplify the method of Agrobacterium-mediated T-DNA transformation by skipping the preincubation step. The method was applied to deliver transgenes for genome editing, such as CRISPR/Cas9 DNA. SnLazy1 locus, considered to be orthologs of tomato Lazy1, was edited using the CRISPR/Cas9 system in S. nigrum. Two independent deletion snlazy1-cr alleles were successively inherited and showed stem growth in a relatively downward direction. Our method offers rapid and simple procedure for gene transformation and genome editing that could be applicable for the enhancement of beneficial traits for precision plant breeding and engineering quantitative trait loci in S. nigrum.

Our study shows for the first time a complete guabiroba micropropagation system with acclimatized plants. BA was the best plant growth regulator for multiplication and IBA for rooting. Campomanesia xanthocarpa O. Berg (Myrtaceae), popularly known as guabiroba, is a woody species native to Brazil, important for its potential as a medicinal plant and fruit tree. For the first time, this study shows a complete system of micropropagation for this species. For this, nodal segments with two axillary buds each were used as starting material. Plant Preservative Mixture™ (0.1%) added to culture media was efficient in controlling contamination throughout the culture process. Two formulations of culture medium were compared for in vitro establishment. 2-Isopentenyladenine, 6-benzyladenine, kinetin and zeatin were tested during the multiplication step. Woody plant medium (WPM) was appropriate for all culture steps and, during the multiplication process, 2.2 µM BA induced the best numbers of new shoots per explant during three subcultures (3.0–3.5 per month). For rooting of microcuttings, a rate of 53% was reached in the WPM supplemented with 4.9 µM indol-3-butyric acid. A plastic box containing a mixture of commercial substrate and vermiculite (1:1 v/v) was used for plantlet acclimatization, allowing 52% of survival after two months. In conclusion, a complete micropropagation protocol was developed providing healthy plants. Further studies are needed to improve multiplication and survival rates.

Over the past decades, crop yields have risen in parallel with increasing use of fossil fuel–derived nitrogen (N) fertilizers but with concomitant negative impacts on climate and water resources. There is a need for more sustainable agricultural practices, and biological nitrogen fixation (BNF) could be part of the solution. A variety of nitrogen-fixing, epiphytic, and endophytic plant growth–promoting bacteria (PGPB) are known to stimulate plant growth. However, compared with the rhizobium-legume symbiosis, little mechanistic information is available as to how PGPB affect plant metabolism. Therefore, we investigated the metabolic changes in roots of the model grass species Setaria viridis upon endophytic colonization by Herbaspirillum seropedicae SmR1 (fix+) or a fix− mutant strain (SmR54) compared with uninoculated roots. Endophytic colonization of the root is highly localized and, hence, analysis of whole-root segments dilutes the metabolic signature of those few cells impacted by the bacteria. Therefore, we utilized in-situ laser ablation electrospray ionization mass spectrometry to sample only those root segments at or adjacent to the sites of bacterial colonization. Metabolites involved in purine, zeatin, and riboflavin pathways were significantly more abundant in inoculated plants, while metabolites indicative of nitrogen, starch, and sucrose metabolism were reduced in roots inoculated with the fix− strain or uninoculated, presumably due to N limitation. Interestingly, compounds, involved in indole-alkaloid biosynthesis were more abundant in the roots colonized by the fix− strain, perhaps reflecting a plant defense response.

Summary: Upon fertilization, the ovary increases in size and undergoes a complex developmental process to become a fruit. We show that cytokinins (CKs), which are required to determine ovary size before fertilization, have to be degraded to facilitate fruit growth. The expression of CKX7, which encodes a cytosolic CK-degrading enzyme, is directly positively regulated post-fertilization by the MADS-box transcription factor STK. Similar to stk, two ckx7 mutants possess shorter fruits than wild type. Quantification of CKs reveals that stk and ckx7 mutants have high CK levels, which negatively control cell expansion during fruit development, compromising fruit growth. Overexpression of CKX7 partially complements the stk fruit phenotype, confirming a role for CK degradation in fruit development. Finally, we show that STK is required for the expression of FUL, which is essential for valve elongation. Overall, we provide insights into the link between CKs and molecular pathways that control fruit growth. : Di Marzo et al. establish that defects in Arabidopsis fruit size are accompanied by alterations in the metabolism of the plant hormone cytokinin, which is critical for cell elongation. SEEDSTICK influences fruit elongation by directly regulating cytokinin degradation via CKX7 and indirectly modulating the expression of the MADS-box gene FRUITFULL. Keywords: Arabidopsis, cell elongation, CKX7, cytokinins, FRUITFULL, fruit size, MADS-box, SEEDSTICK

Olive (Olea europaea L.) is an economically important crop because of its fruit and oil. Successful olive micropropagation is highly dependence on cultivar, shoot proliferation rate, which is generally low, the rooting of micropropagated olive plantlets is difficult, and the rate of post-transplanting losses is high. in addition, hyperhydricity, a common problem in vitro culture was found to be prevalent. the aim of this study was to establish a micropropagation system for the Turkish O. europaea L. cv. Gemlik. Initially, five different basal media were tested to determine appropriate medium for establishment of in vitro culture and Woody Plant Medium (WPM) was the most efficient. Nodal explants were cultured on WPM containing different plant growth regulators (PGRs) for shoot regeneration. Maximum regeneration frequency and number of shoots per explant were achieved from nodal explants cultured on WPM supplemented with 4.0 mg/L 6-benzyladenine (BA). However, all cultures showed high hyperhydricity and an experimentation was also conducted to resolve the hyperhydricity problem. Hyperhydricity was prevented by changing the gelling agent to Agar-Agar. the shoots regenerated from nodal explants and still attached to initial woody nodal explant were transferred to four different medium formulations each containing 2.0 mg/L zeatin (ZEA) for shoot elongation. Modified Olive Medium (MOM2: OM with three times the concentrations of KNO3) fortified with 2.0 mg/L ZEA was found to be the best for shoot elongation. the elongated shoots were rooted on Olive medium (OM) containing 160 mg/L Putrescine, 1.5 mg/L naphthaleneacetic acid (NAA), 30 g/L mannitol and solidified with 0.65% (w/v) Agar-Agar. Finally, all plantlets were successfully acclimatized in a climate chamber and the plants were transferred to greenhouse conditions. (C) 2019 SAAB. Published by Elsevier B.V. All rights reserved., Ege University Scientific Research Projects Coordination UnitEge University [09-MUH-010], This work was supported by Ege University Scientific Research Projects Coordination Unit [grant number: 09-MUH-010]. All of the experiments were carried out at the Bioengineering Department of Ege University. the authors are grateful to Mark Smedley for critically reviewing the manuscript.

The content of indole-3-acetic (IAA), gibberellic (GA3), abscisic acids (ABA), and cytokinins—zeatin (Z), zeatin glucoside (ZG), zeatin riboside (ZP), isopentenyladenin (iР), and isopentenyladenosine (iРА)—was determined using the method of high-performance liquid chromatography in fern Polystichum aculeatum gametophytes at different stages of morphogenesis in vitro culture. It was shown that, at the stage of spatulate prothallium development, gametophytes contained significant amounts of GA3 and IAA, while the content of ABA and cytokinins was low. The inactive ZG and active iP were dominant. At the stage of cordiform thallus formation, the level of GA3 increased by 1.6, IAA by 2.4, and ABA by 1.7 times. The content of inactive iPA increased twice, significantly increased the level of active ZR and iP. At the development stage of sporophyte on the surface of gametophyte thallus, the levels of IAA, ABA, and GA3 decreased. The accumulation of inactive ZG and decrease in the content of active zeatin and zeatin riboside were documented. At all stages of gametophytes’ morphogenesis, GA3 was dominant, and its highest content was detected during the development of archegonia and antheridia. The pattern of gibberellic acid and zeatin riboside accumulation has shown the key role of these hormones in the regulation of growth processes and the development of reproductive structures of P. aculeatum gametophytes.

In order to investigate the possibility for in in vitro fast regeneration of Dianthus caryophyllus, different concentrations of Kinetin (Kin), 2,4-Dichlorophenoxy Acetic Acid (2,4-D) had been tested for induction of callus by leaves and stems explant using Murashige and Skoog (MS) medium. After two months in culture, response callus in the induction rate, fresh and dry weight, texture and color were evaluated. MS medium that contained 4.5 mg.L-1 2, 4-D was suitable for callus induction with leaf explants. The combination of 0.4 mg.L-1 Kin and 2.0 mg.L-1 2, 4-D also demonstrated a wonderful induction of callus on stem explants. In addition to the culture medium complemented by Kin and 2, 4-D, the influence of Zeatin at various concentrations (0.0, 0.4, 0.8 or 1.0 mg.L-1) was assessed. In MS medium that contained 0.4 mg.L-1 Kin+ 2.0 mg.L-1 2,4-D+ 1.0 mg.L-1 Zeatin, rapid callus induction and also more callus proliferation from stem explants were detected. Results indicate on callus induction that, Zeatin was more successful than Kin or 2, 4-D, but other combinations directly developed a shoot. Callus obtained from stems explant was friable, white and yellow, while callus from leaf explants was green.

Primary thickening determines bamboo yield and wood property. However, little is known about the regulatory networks involved in this process. The present study identified a total of 58,652 genes and 521 miRNAs via transcriptome and small RNA sequencing using the underground thickening shoot samples of wild type (WT) Moso bamboo (Phyllostachys edulis) and a thick wall (TW) variant (P. edulis cv. Pachyloen) at five developmental stages (WTS1/TWS1-WTS5/TWS5). A total of 11,636 (54.05%) differentially expressed genes (DEGs) and 515 (98.85%) differentially expressed miRNAs (DEmiRs) were identified from the WT, TW, and WTTW groups. The first two groups were composed of four pairwise combinations each between two successive stages (WTS2/TWS2_vs_WTS1/TWS1, WTS3/TWS3_vs_WTS2/TWS2, WTS4/TWS4_vs_WTS3/TWS3 and WTS5/TWS5_vs_WTS4/TWS4), and the WTTW group was composed of five between two relative stages (TWS1–5_vs_WTS1–5). Additionally, among the phytohormones, zeatin (ZT) showed more remarkable changes in concentrations than indole-3-acetic acid (IAA), gibberellic acid (GA3), and abscisic acid (ABA) throughout the five stages in the WT and the TW groups. Moreover, 118 sites were identified for 590 miRNA-mRNA pairs via degradome sequencing. The dual-luciferase reporter assay confirmed that 14 miRNAs bound to 12 targets. Fluorescence in situ hybridization (FISH) localized miR166 and miR160 in the shoot apical meristem (SAM) and the procambium of Moso bamboo shoots at the S1 stage. Thus, primary thickening is a complex process regulated by miRNA-gene-phytohormone networks, and the miRNAome and transcriptome dynamics regulate phenotypic plasticity. These findings provide insights into the molecular mechanisms underlying wood formation and properties and propose targets for bamboo breeding.

Robusta coffee is a major commercial crop in the Central Highland of Vietnam with high economic and export value. However, this crop is adversely affected by various pathogens, particularly nematodes. This study aimed to screen active anti-nematode rhizobacterial strains for sustainable coffee production. Among more than 200 isolates, the isolate TUN03 demonstrated efficient biocontrol with nearly 100% mortality of J2 coffee nematodes Meloidogyne spp. and 84% inhibition of nematode egg hatching. This active strain was identified as Pseudomonas aeruginosa TUN03 based on its 16S rRNA gene sequence and phylogenetic analysis. In greenhouse tests, the strain TUN03 significantly reduced the coffee nematode population in the rhizome-soil with an 83.23% inhibition rate and showed plant growth-promoting effects. Notably, this is the first report of the nematicidal effect of P. aeruginosa against coffee nematodes. This potent strain further showed an antifungal effect against various crop-pathogenic fungi and was found to be the most effective against Fusarium solani F04 (isolated from coffee roots) with a 70.51% inhibition rate. In addition, high-performance liquid chromatography analysis revealed that this bacterial strain also secretes plant growth regulators including indole acetic acid (IAA), gibberellic acid (GA3), kinetin, and zeatin in significant amounts of 100, 2700, 37, and 9.5 µg/mL, respectively. The data from this study suggest that P. aeruginosa TUN03 may be a potential biocontrol agent and biofertilizer for the sustainable production of Robusta coffee and other crops.

2-Methylthio-N7-methyl-cis-zeatin (1) was isolated from the culture broth of Streptomyces sp. 80H647 along with 2 known purine derivatives, 5′-methylthioinosine (2) and AT-265 (dealanylascamycin, 3). The structure elucidation of compound 1 was accomplished by high-resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR) analyses. It inhibited the growth of Plasmodium falciparum 3D7 with a GI50 of 2.4 µm and had no effect on the growth of Arabidopsis at 2 µm. This is the first report of an N7-methylated zeatin-type natural product from Streptomyces and as an antimalarial compound.

Compelling evidence demonstrates that root-derived cytokinins (CKs) contribute to shoot growth via long-distance transport; therefore, we hypothesized that an increase in root-derived CKs enhances shoot growth. To demonstrate this, we grafted Arabidopsis Col-0 (WT) scion onto rootstock originated from WT or a double-knockout line of CK receptors AHK2 and AHK3 (ahk23) because the knockout line over accumulates CKs in the body due to feedback homeostasis regulation. The grafted plants (scion/rootstock: WT/WT and WT/ahk23) were grown in vermiculite pots or solid media under high and low nitrogen regimes for vegetative growth and biochemical analysis. The root-specific deficiency of AHK2 and AHK3 increased root concentrations of trans-zeatin (tZ)-type and N6-(Δ2-isopentenyl) adenine (iP)-type CKs, induced CK biosynthesis genes, and repressed CK degradation genes in the root. Shoot growth, shoot concentrations of tZ-type CKs, and shoot expression of CK-inducible marker genes were consistently larger in the WT/ahk23 plants than in the WT/WT plants. Moreover, the root-specific deficiency of AHK2 and AHK3 enhanced shoot growth in the WT scion more strongly than in the ahk23 scion. Given that tZ-type CKs are predominantly produced from iP-type CKs in the root and xylem-mobile, it is concluded that the root-specific reduction of CK perception would enhance shoot growth by increasing the amount of root-derived tZ-type CKs and their perception by the shoot. This study will present a novel approach to improve plant growth and productivity.

Background Liquid suspension culture efficiently proliferates plant cells and can be applied to ferns because it rapidly increases the fresh weight of gametophytes. This study assessed gametophyte proliferation and sporophyte production of Pteridium aquilinum var. latiusculum using a suspension culture method. Results The growth curve linear phase of gametophyte cells was confirmed between 9 and 18 days of culture, and the subculture cycle was determined to be 2 weeks. A double-strength MS medium (fresh weight, 18.0 g) containing 2% sucrose and NH4+:NO3− (120 mM, 40:80) was found to be the optimal liquid medium. Gametophytes obtained after suspension culture for 18 days did not normally form sporophytes in an ex vitro soil environment. However, this issue was resolved after changing the culture type or extending the culture period to 6 weeks. A short suspension culture period increased the fresh weight of fragmented and homogenized gametophytes but yielded numerous relatively immature gametophytes (globular forms of branching gametophytes, BG). Furthermore, differences in gametophyte morphogenesis and development were indicated by changes in endogenous phytohormone content. BG with immature development exhibited high accumulation of zeatin, jasmonic acid, and salicylic acid, and relatively low levels of abscisic acid and indole-3-acetic acid. The immature development of gametophytes directly affected sporophyte formation. Conclusions This study maximized the advantages of liquid suspension culture using eastern bracken gametophytes and provides data to resolve any associated issues, thus facilitating efficient bracken production.

Salinity stress results in significant losses in plant productivity and loss of cultivable lands. Although Pongamia pinnata is reported to be a salt-tolerant semiarid biofuel tree, the adaptive mechanisms to saline environments are elusive. Despite a reduction in carbon exchange rate (CER), the unchanged relative water content provides no visible salinity induced symptoms in leaves of hydroponic cultivated Pongamia seedlings for 8 days. Our Na+ -specific fluorescence results demonstrated that there was an effective apoplastic sodium sequestration in the roots. Salinity stress significantly increased zeatin (~5.5-fold), and jasmonic acid (~3.8-fold) levels in leaves while zeatin (~2.5-fold) content increased in leaves as well as in roots of salt-treated plants. Metabolite analysis suggested that osmolytes such as myo-inositol and mannitol were enhanced by ~12-fold in leaves and roots of salt-treated plants. Additionally, leaves of Pongamia showed a significant enhancement in carbohydrate content, while fatty acids were accumulated in roots under salt stress condition. At the molecular level, salt stress enhanced the expression of genes related to transporters, including the Salt Overly Sensitive 2 gene (SOS2), SOS3, vacuolar-cation/proton exchanger, and vacuolar-proton/ATPase exclusively in leaves, whereas the Sodium Proton Exchanger1 (NHX1), Cation Calcium Exchanger (CCX), and Cyclic Nucleotide Gated Channel 5 (CNGC5) were up-regulated in roots. Antioxidant gene expression analysis clearly demonstrated that peroxidase levels were significantly enhanced by ~10-fold in leaves, while Catalase and Fe-superoxide Dismutase (Fe-SOD) genes were increased in roots under salt stress. The correlation interaction studies between phytohormones and metabolites revealed new insights into the molecular and metabolic adaptations that confer salinity tolerance to Pongamia.

Photoperiod is dominant environmental factor that controls plant growth and development. Even though research on plants response to photoperiod is significant in agriculture, molecular mechanisms of garlic in response to photoperiod remain largely unknown. In the current investigation, 3 months old garlic plants were treated with long day (LD) and short day (SD) for 10 and 20 days after treatment (DAT). Liquid chromatography-mass spectrometry (LC-MS) analysis of phytohormones exhibited that indole-3-acetic acid (IAA), zeatin riboside (ZR) and salicylic acid (SA) were observed maximum under LD at 10 DAT, whereas abscisic acid (ABA), gibberellic acid 3 (GA3), zeatin (ZT) and jasmonic acid (JA) were observed maximum under LD at 20 DAT. Transcriptome sequencing analysis was done to evaluate the transcriptional response to LD and SD. Differentially expressed genes (DEGs) were detected to have pathway enrichment. i.e., DNA binding transcription factor activity, transcription regulator activity, transferase activity, transferring hexosyl groups, and sequence specific-DNA binding activity, plant hormone signal transduction, circadian rhythm-plant, biosynthesis of amino acids, phenylpropanoid biosynthesis, and starch and sucrose metabolism. Furthermore, 28 and 40 DEGs were identified related to photoperiod and hormone signaling, respectively and their interaction in response to LD and SD were discussed in detail. Outcomes of current investigation might be useful to provide novel resources for garlic bulb formation in response to photoperiod.

Isolation and purification of cyanobacteria from kafr El-Sheikh soil samples revealed that, two isolates (Anabaena cylindrica and Nostoc clacicola) were acquired as bacterial free cyanobacteria and nitrogen fixed. These cynobacteria isolates were produced auxin (Indole-3-acetic acid), gibberellins (Gibberellic acid) and cytokinin (Zeatin). Therefore, when inoculation with Anabaena cylindrica, Nostoc clacicola and their mixture were significantly increased the plant height, number of spikes/m2, 1000-grain weight, grain yield, straw yield protein content% on wheat crop and total counts of cyanobacteria in soil.

Objective. To study the possibility of production of physiologically active substances by the as-sociation of micromycetes Trichoderma harzianum 128, which is used for enrichment composted substrates based on chicken litter. Methods. Microbiological, physiological, accumulative thin lay-er chromatography, high-performance liquid chromatography (HPLC / MS). Results. T. harzianum 128 produces a significant amount of physiologically active growth stimulanting substances. Soak-ing of corn seeds in the culture liquid of micromycetes association, diluted with water in 100– 10,000 times, provides a reliable growth stimulation of seedlings and indicates the absence of phy-totoxicity in microorganisms. The instrumental determination of the content of exogenous phyto-hormones in pre-purified and concentrated phytohormonal extracts shows a significant amount of auxins in a culture fluid — their total amount reaches 18.33 μg/g of dry biomass of the producer, and of cytokinins, in particular, isopentenylidenidine (5.6 μg/g of dry biomass) and zeatin (0.88 μg/g dry biomass). Association T. harzianum 128 in small quantities produces gibberellic acids — GK3 (0.34 μg/g dry biomass) and GK4 — 0.23 μg/g of dry biomass). Absorbent acid was also found in the culture fluid (5.3 μg/g dry biomass), but its amount is four times less than the cor-responding measures in the known strain T. viride F100001, which was used as a positive control in the studies. While the introduction of association T. harzianum 128 into the composted chicken litter substrate, the obtained compost shows high auxin and cytokinin activity. Conclusion. Phyto-hormones, which are produced by the micromycetes association of T. harzianum 128, can positively influence the growth and development of plants, play a protective role in adverse environmental conditions. After introduction of the investigated fungi association to a composted substrate on the basis of chicken litter it accumulates significant amounts of physiologically active substances of auxin and cytokinin action. Under these conditions compost acquires new qualitative features.

Metasequoia glyptostroboides Hu et Cheng (dawn redwood), a known relict living fossil, is listed as a Class I rare and endangered tree in China. An efficient in vitro propagation protocol was established in this study to overcome the shortage of germplasm that cannot be compensated by conventional reproduction and as a way to preserve this tree. This objective was achieved by testing the effect of plant growth regulators (PGRs) on shoot propagation and root formation. Axillary shoots, which could be induced on PGR-free woody plant medium (WPM), were efficiently propagated on WPM supplemented with 16.0 µM zeatin and 2.5 µM indole-3-butyric acid. Improved rooting was possible on WPM supplemented with 0.05 µM α-naphthaleneacetic acid. Rooting was possible both in vitro in vermiculite-based PGR-free liquid culture and ex vitro in plastic bags containing perlite: vermiculite (1:1, v/v). This effective in vitro micropropagation protocol for M. glyptostroboides serves as a way to conserve this tree and provides an opportunity for mass production to alleviate strain on natural populations.

Phosphate (Pi) is an essential nutrient for all organisms. Roots are underground organs, but the majority of the root biology studies have been done on root systems growing in the presence of light. Root illumination alters the Pi starvation response (PSR) at different intensities. Thus, we have analyzed morphological, transcriptional and physiological responses to Pi starvation in dark-grown roots. We have identified new genes and pathways regulated by Pi starvation that were not described previously. We also show that Pi-starved plants increase the cis-zeatin (cZ) : trans-zeatin (tZ) ratio. Transcriptomic analyses show that tZ preferentially represses cell cycle and PSR genes, whereas cZ induces genes involved in cell and root hair elongation and differentiation. In fact, cZ-treated seedlings show longer root system as well as longer root hairs compared with tZ-treated seedlings, increasing the total absorbing surface. Mutants with low cZ concentrations do not allocate free Pi in roots during Pi starvation. We propose that Pi-starved plants increase the cZ : tZ ratio to maintain basal cytokinin responses and allocate Pi in the root system to sustain its growth. Therefore, cZ acts as a PSR hormone that stimulates root and root hair elongation to enlarge the root absorbing surface and to increase Pi concentrations in roots.

Despite an increase in application spectrum of rare earth elements in agriculture, all studies show that the suitable accumulation of rare earth elements can improve the crop seedling growth, but there is little research about REEs on physiological mechanisms of crops at reproductive stages. Therefore, this study was conducted to examine the possible potential benefits of lanthanum chloride (LaCl3) on the senescence and grain yield responses of maize. In this study, maize seeds were pre-treated by soaking with LaCl3 at the concentrations of 0 (CK), 400 (LC1), 800 (LC2) and 1200 (LC3) μmol/L, to evaluate its effect on the green leaf area, chlorophyll contents, photosynthesis, antioxidants, endogenous hormones in the later crop growth stages. The results show that LC1 and LC2 treatments evidently increase green leaf area, above ground dry biomass, accompanied by a distinct increase in the chlorophyll contents, and photosynthetic capacity, which promote the ear characteristics and grain yield of maize. In addition, LC1 and LC2 treatments simultaneously increase the activities of antioxidants, including superoxide dismutases, catalases, peroxidases, soluble protein, and enhanced levels of auxin, gibberellin and zeatin, following a dose-response tendency. Themalondialdehyde and abscisic acid levels transiently increase with the progression in the growth stage of the crop but are markedly decreased at LC1 and LC2 treatments, while LC3 treatment has no significant effect on malondialdehyde and even accelerates the accumulation of abscisic acid in maize leaves. Our data suggest that seed priming with LaCl3 at a suitable concentration range (400–800 μmol/L) can prolong the functional periods of leaves, increase photosynthetic capacity, enhance antioxidant activity, and alter endogenous hormone levels at reproductive stages, resulting in delaying leaf senescence rate and increasing yield. However, the moderate concentration of LaCl3 for maize is LC2 (800 μmol/L), and can be effectively used to improve grain yield of maize.

Background : The extension of the blueberry industry in China is restricted by the low performance of proliferation coefficient, transplanting survival rate and the long cycle production. Hypothesis : We hypothesized the suitable medium with optimal concentration and type combination would improve the survival rate of Vaccinium corymbosum. Species studied : Vaccinium corymbosum L. cultivar ‘O’Neal. Study site and years of study : Our study was conducted in Yunnan Breeding and Cultivation Research and Development Center of Endangered and Daodi Chinese medicinal materials, Yunnan University of Chinese Medicine since November 2015. Methods : Efficient protocol of plant regeneration about Southern highbush blueberry (cultivar ‘O’Neal) was established using annual shoots via single factor and orthogonal experiments. Results : Olive medium with 2.0 mg·L -1 zeatin was found to be most suitable for initiation culture. The highest callus induction and bud formation rate were determined with 93.67 % and 95.57 %, respectively. Furthermore, as the germination of axillary buds, numerous shoots were formed with the proliferation coefficient (> 60). Well-developed shoots were obtained using rejuvenation culture on half-strength Olive medium supplemented with combination of 2.0 mg·L -1 indole-3-butyric acid, 1.0 mg·L -1 naphthaleneacetic acid, 0.01 mg·L -1 chlormequat chloride and 0.5 g·L -1 activated charcoal. The rooting rate could reach to 100 % using 2 cm length of well-developed shoots transferred into the 5:1 sterilized peat:perlite, which was enhanced from 27.61 up to 95 % after transplanting to the field. Conclusions : An efficient system for plant regeneration from bud induction to transplanting to the field was established to maintain the characteristics of southern highbush blueberry varieties.

Barnyard grass (Echinochloa crus-galli) is a troublesome graminaceous weed infesting rice fields in the Yangtze River Basin, China. However, the effects of barnyard grass on rice root physiology are unclear. In this study, the effects of barnyard grass, planted at different densities (ranging from 2-8 plants m-2), on rice performance were evaluated, including chlorophyll fluorescence parameters, Rubisco activity, root oxidation activity, and the zeatin + zeatin riboside concentration. The results indicated that rice photosynthesis and physiological characteristics decreased as the density of barnyard grass increased. The rice net photosynthetic rate significantly declined and ranged between 17.3-10.5% compared with the control (0 barnyard grass plants m-2). The results showed that rice grain yields decreased to 58% when barnyard grass was planted at a density of 8 plants m-2. We found that barnyard grass can reduce the Rubisco activity, leaf photosynthetic capacity, and energy conversion efficiency in rice, thus resulting in the reduced rice yield.

Ligaria cuneifolia (R. et P.) Tiegh (Loranthaceae), known as liga, muérdago criollo, or Argentinean mistletoe, is a hemiparasitic plant with a broad distribution in central and northern Argentina. Pharmacological studies showed that L. cuneifolia extracts have hypolipemic, antioxidant, antibacterial, and immunomodulatory effects. We have established callus cultures from embryo and haustoria fragments. The highest frequency of callus formation from embryos (85%) was obtained on White medium with 4% (w/v) sucrose and 2.5 µM 1-naphtalene acetic acid and 9.2 µM kinetin as plant growth regulators (PGRs). From haustoria, the best result (35%) was obtained on Gamborg medium with 3% (w/v) sucrose and 0.45 µM 2,4-dichlorephenoxyacetic acid and 0.47 µM zeatin as PGRs. Thin layer chromatography showed that callus methanolic extract (2.5% w/v) had a lower content of flavonoids and proanthocyanins as compared to the wild plant (5% w/v for leaves, stems, and flowers), but a higher content of hydroxycinnamic acids. High performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS) showed the presence of quercetin glycosides and phenolic acids in the methanolic extracts both from the parent plant and the callus obtained from embryo. Fil: Ricco, María Valeria. Universidad Maimónides. Facultad de Ciencias de la Salud. Carreras de Farmacia y Bioquímica. Cátedra de Farmacobotánica y Farmacognoscia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Bari, Martín León. Universidad Maimónides. Facultad de Ciencias de la Salud. Carreras de Farmacia y Bioquímica. Cátedra de Farmacobotánica y Farmacognoscia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Bagnato, Federico. Universidad Maimónides. Facultad de Ciencias de la Salud. Carreras de Farmacia y Bioquímica. Cátedra de Farmacobotánica y Farmacognoscia; Argentina Fil: Cornacchioli, Carolina. Universidad Maimónides. Facultad de Ciencias de la Salud. Carreras de Farmacia y Bioquímica. Cátedra de Farmacobotánica y Farmacognoscia; Argentina Fil: Laguía Becher, Melina. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico. Departamento de Estudios Biomédicos y Biotecnológicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Spairani, Leonardo Ulises. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; Argentina. Universidad Maimónides. Facultad de Ciencias de la Salud. Carreras de Farmacia y Bioquímica. Cátedra de Farmacobotánica y Farmacognoscia; Argentina Fil: Posadaz, Ariana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Luis. Facultad de Turismo y Urbanismo; Argentina Fil: Dobrecky, Cecilia Beatriz. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Tecnología Farmacéutica; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Farmacología. Cátedra de Farmacobótanica; Argentina Fil: Ricco, Rafael Alejandro. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Farmacología. Cátedra de Farmacobótanica; Argentina Fil: Wagner, Marcelo Luis. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Farmacología. Cátedra de Farmacobótanica; Argentina Fil: Alvarez, Maria Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Maimónides. Facultad de Ciencias de la Salud. Carreras de Farmacia y Bioquímica. Cátedra de Farmacobotánica y Farmacognoscia; Argentina

The effect of N6(3-hydroxybenzyl)adenine (meta-Topolin—mT) was compared with that of N6-benzylaminopurine (BAP) and zeatin at the proliferation stage of micropropagation of red-fleshed Actinidia chinensis var. chinensis ‘Zes006’ in two separate experiments. Shoot number, shoot weight, leaf number and leaf area were significantly higher in mT-supplemented media compared with BAP or zeatin. When transferred to rooting media, plantlets that were propagated in mT-supplemented media readily produced roots, enabling easy acclimation to the greenhouse, whereas none of the plantlets propagated in BAP- or zeatin-supplemented media produced roots. Using 12 pairs of Simple Sequence Repeat primers designed for A. chinensis var. chinensis, a very low rate of somaclonal variation was detected at some loci in plantlets produced in zeatin- (1.04%), BAP- (0.4%) as well as in mT- (0.2%) supplemented media. Overall, mT in equimolar concentrations was the better cytokinin for tissue culture of ‘Zes006’ kiwifruit and may well be applicable to many other kiwifruit genotypes. Supplementation of media with meta-Topolin for in vitro propagation of the red-fleshed kiwifruit cultivar ‘Zes006’ enhanced better shoot proliferation, giving healthy plantlets that were easier to acclimatize to the greenhouse environment compared with media supplemented with 6-benzylaminopurine or zeatin. It also induced a lower rate of somaclonal variation, as detected by SSR markers.

Physalis pruinosa, also known as groundcherry, produces a small, yellow, highly nutritious edible fruit that is enveloped by a papery husk. In order for the potential of large-scale production of P. pruinosa fruit to be realized, undesirable characteristics, such as an unmanageable, sprawling growth habit and extensive fruit drop, need to be improved by exploiting approaches available through plant breeding, genetic engineering, and gene editing. In this study, we established plant regeneration and Agrobacterium tumefaciens-mediated methods to allow application of genetic engineering and gene editing of P. pruinosa. Cotyledon and hypocotyl explants from 7 to 8-day-old in vitro-grown seedlings were assessed for plant regeneration. Explants were cultured for 2 weeks on a Murashige and Skoog salts-based medium that contained 2 mg/L zeatin followed by transfer to medium containing 1 mg/L zeatin. Only hypocotyl explants regenerated shoots. Hypocotyl explants were infected with Agrobacterium tumefaciens strain AGL1 containing the pJL33 binary vector that has the green fluorescent protein reporter and neomycin phosphotransferase II (nptII) selectable marker genes. After cocultivation, explants were cultured on selective plant regeneration medium that contained 50, 100, 200, 250, and 300 mg/L kanamycin to determine the most effective level for efficient recovery of transgenic lines. Based on PCR analysis for the presence of the nptII gene, medium containing 200 mg/L kanamycin resulted in the highest transformation efficiency at 24%. This study sets the foundation for future genetic engineering and gene editing approaches for improvement of P. pruinosa. Methodology for regeneration and transformation of Physalis pruinosa is a key component for the genetic improvement of this underutilized fruit crop for future agricultural production.

During rooting of both cuttings and grafted scions of tree peony (Paeonia suffruticosa Andr.) cultivar ‘Fengdanbai’, the anatomical structure, the contents of endogenous hormones (indole acetic acid, IAA; zeatin, ZT; gibberellin, GA3; and abscisic acid, ABA), and the activities of IAA oxidase (IAAO), peroxidase (POD), and polyphenol oxidase (PPO) were observed. The results showed that the rooting processes in cuttings and grafted scions were similar, but that the critical period of rooting in cuttings was earlier than in grafts (cuttings: 18–20 days; scions: 38–40 days). IAA content showed a direct correlation with rooting, with the peak value appearing as the adventitious roots were breaking through the epidermis in both cuttings and grafts (cuttings: 20 days; scions: 38 days). ZT and GA3 promoted adventitious rooting, and ABA inhibited it. The peak values of the IAA:ABA and IAA:ZT ratios appeared at the same time as the IAA peak (cuttings: 20 days; scions: 38 days), which indicated that these values were closely related to the occurrence of adventitious roots. Changes in the activities of IAAO, POD, and PPO, which modify IAA levels, indicated that there were no direct relationships between these three enzymes and adventitious root formation in cuttings or grafts. These results provide a basis for further study of adventitious root formation in the ornamental tree peony.

Tissue cultures are the only effective way to proliferate this valuable species (Daphne mezereum). These researches may help in solving the problem of reproduction of other woody plants. Daphne mezereum L. commonly known as February daphne or mezereon is a decorative shrub from the family Thymelaeaceae. It is a valuable nursery plant due to its high ornamental values, but its propagation by traditional methods is ineffective, therefore, little profitable. Micropropagation may be a good alternative way to produce this ornamental shrub. The experiment aimed to examine the effect of cytokinins (meta-Topolin, benzyladenine, and zeatin) and other growth regulators (gibberellic acid GA3 and auxin 1-naphthalene acetic acid NAA) added to the Murashige and Skoog (MS) and Woody Plant Medium (WPM) nutrients on regeneration of explants of D. mezereum ‘Alba’. In the all treatments containing plant growth regulators (PGR), 100% regeneration of explants has been observed. The highest number of shoots, after 6 weeks of culture, was produced on MS medium with 1 mg·L−1 BA and 0.1 mg·L−1 NAA. The longest shoots were produced on MS medium with 0.1 mg·L−1 of gibberellic acid (GA3) and 1 mg·L−1 of meta-Topolin (mT). Generally, the type and concentration of plant growth regulators had an essential effect on regeneration and growth of shoots of Daphne mezereum ‘Alba’ in the in vitro culture.