Polyhalite as an alternative potassium fertilizer for sweetpotatoes

BackgroundQuantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR) is a sensitive technique for quantifying gene expression levels. One or more appropriate reference genes must be selected to accurately compare mRNA transcripts across different samples and tissues. Thus far, only actin-2 has been used as a reference gene for qRT-PCR in chicory, and a full comparison of several candidate reference genes in chicory has not yet been reported.ResultsSeven candidate reference genes, including nicotinamide adenine dinucleotide dehydrogenase (NADHD), actin (ACT), β-tubulin (TUB), glyceraldehyde-3-phosphate-dehydrogenase (GADPH), histone H3 (H3), elongation factor 1-alpha (EF) and 18S rRNA (rRNA) were selected to study the expression stability for normalisation of gene expression in chicory. Primer specificity and amplification efficiency were verified for each gene. The expression stability of these genes was analysed across chicory root and leaf tissues using geNorm, NormFinder and BestKeeper software. ACT, EF, and rRNA were the most stable genes as identified by the three different analysis methods. In addition, the use of ACT, EF and GAPDH as reference genes was illustrated by analysing 1-FEHII (FEHII) expression in chicory root and leaf tissues. These analyses revealed the biological variation in FEHII transcript expression among the tissues studied, and between individual plants.ConclusionsgeNorm, NormFinder, and BestKeeper analyses indicated that ACT, EF and rRNA had the highest expression stability across leaf and root tissues, while GAPDH and NADHD showed relatively low expression stability. The results of this study emphasise the importance of validating reference genes for qRT-PCR analysis in chicory. The use of the most stable reference genes such as ACT and EF allows accurate normalisation of gene expression in chicory leaf and root tissues.

Potassium (K) fertilization is a crucial component of sweet potato (Ipomoea batatas L.) production. The basis for K fertilizer recommendations in sweet potato production varies greatly and relies on studies conducted in the late 1950s–1970s. Changes in agronomic practices and increasing costs emphasize the need to revisit fertilizer recommendations. A field experiment was conducted to investigate the impact of seven different K fertilizer (K2O) application rates on sweet potato storage root yield, tissue K concentration, and economic implications in Mississippi. Incremental applications of K fertilizer did not influence sweet potato yield at any grade. Leaf tissue K concentration exhibited a quadratic trend in response to K fertilizer rate, with maximum leaf and root K content achieved at 269 and 404 kg·ha−1 K2O, respectively. Both the predicted K application rate for maximum yield and maximum profitability were the same, at 174 kg·ha−1 K2O. Accordingly, comparable sweet potato yields were achieved while applying substantially less fertilizer than the recommended rate. Further research is warranted to examine the impacts of only potassium fertilizer applications on soil characteristics and temporal trends in sweet potato potassium uptake, as well as refine fertilization recommendations for sweet potato production.

The techniques for cultivating the young intact barley seedlings used in these absorption experiments are described in some detail. Sets of twelve selected seedlings were used and all data obtained refer to these units. In the experiments, proper absorption took place from dilute solutions of either potassium chloride alone or a mixture of potassium bromide and chloride, the total concentration of which was 0.001 M. Calcium sulphate was also present in all experimental solutions. Chloride is absorbed from the medium at an almost constant speed for a number of hours. This absorption is not influenced by subsequent distribution. At first, the root tissue tends to retain a large proportion of the chloride absorbed at the expense of the transfer of ions to the shoots. Gradually the transfer increases until a constant value is reached within a few hours. Identical results were obtained for total halides if absorption took place from a mixture of chloride and bromide. In addition it was found that chloride and bromide were absorbed at a ratio, which was constant and about twice as high as the ratio for the ions present in the medium. This ratio remained constant even in the dark when total absorption tended to decline slightly. In the transport processes following primary absorption, further discrimination between chloride and bromide ions takes place. The additional screening effect of the root tissue is very small. Nevertheless, important conclusions could be drawn from the behaviour of the Cl/Br ratios of the halides found in roots and shoots. For root tissue this ratio, which must equal the ratio for total absorption at the beginning of the experiment, decreases slightly until a somewhat lower but constant level is reached after a few hours. Although there is no doubt about this decrease for the root tissue, it proved to be so small that the simultaneous increase of the ratio for the shoot tissue was hardly discernable under normal conditions. It became so, if the transfer of ions to the shoot was reduced by a dark treatment. These results could be explained by assuming that the root tissue consists of at least two compartments, differing with respect to the Cl/Br ratio. Ions are brought from the medium into the first compartment by the primary absorption process and then transferred to either the second compartment or via the xylem vessels to the shoots. It is tempting to identify the first compartment with the symplasm of the root tissue, the second one with the vacuole system. The process that takes ions out of the symplasm into the vacuoles prefers bromide ions to chloride ions. Little preference, if any, for either chloride or bromide ions was found for the secretion of ions from the symplasm into the xylem vessels. This is consistent with the idea that the secretion is a simple leakage of a solution out of the tissue. Under conditions of suppressed transfer to the shoots, the accumulation of ions from the symplasm into the vacuoles becomes relatively more important. This causes greater shifts in the Cl/Br ratios found in the different compartments.

A field experiment was carried out during winter (rabi) season 2021–22 at the ICAR-Indian Agricultural Research Institute located at New Delhi to find out the effect of potassium management on yields, nutrient uptake and economics of Indian mustard. Eight treatments combinations of different doses, methods and time of potassium application i.e. No K = 0 kg K/ha; 100% MOP (muriate of potash) as basal; 2 Foliar sprays of KNO3 at branching and before flowering; 50% MOP as basal + 50% MOP as top dressing at branching; 50% MOP as basal + 2 foliar sprays of KNO3 at branching and before flowering; 75% MOP as basal + 25% MOP as top dressing at branching; 75% MOP as basal + one foliar spray of KNO3 at branching; 75% MOP as basal + one foliar spray of KNO3 before flowering were tested. Grain (1.89 t/ha) and straw yields (6.74 t/ha), harvest index (21.88%) and NPK uptake (93.9, 18.5 and 113.3 kg/ha) were significantly higher under 75% MOP as basal + one foliar spray of 2.5% KNO3 before flowering. However, the treatment i.e. 75% MOP as basal + one foliar spray of KNO3 before flowering remained significantly at par with 75% MOP as basal + one foliar spray of KNO3 at branching and 75% MOP as basal + 25% MOP as top dressing at branching in yield and profitability term. Enhanced net returns amounting to 65,873/ha and a benefit: cost ratio of 1.86 were recorded on the application of 75% MOP as basal fertilizer combined with a single foliar spray of KNO3 before flowering. This remained comparable to most treatments, except the control, 100% MOP applied as basal, the method involving two foliar sprays of KNO3 at branching and before flowering, 50% MOP as basal combined with 50% MOP as top dressing at branching, and the approach combining 50% MOP as basal with 2 foliar sprays of KNO3 at branching and before flowering.

The organic acid content of soybean (Glycine max v. Hodgson) root, stem, and leaf tissue was followed for 33 days after germination. Malonate was the predominant acid in leaf and root tissue, whereas fumarate was predominant in the stem. The malonate concentrations of the stem and root showed similar variations with time, but the leaf response was quite different. In nodules from 33-day-old plants, malonate was the predominant acid. Malonate levels in root and nodule tissue of 33-day-old plants were depressed in response to the addition of either nitrate or ammonia. Nodule tissue had a higher malonate concentration on nitrate nitrogen than it did on ammonium nitrogen, whereas root tissue had the higher malonate concentration on ammonium nitrogen. Analysis of organic acid concentrations of roots as a function of age and distance from the root tip in young soybean seedlings revealed a zone consistently high in malate. The malonate level in the entire root rose dramatically in tissue of age 96 to 120 hours.

Changes in freezing tolerance and polypeptide content of spinach and citrus at 5 °C

This article reports salt-induced changes in leaf and root proteomes after wild tomato (Solanum chilense) plants were treated with 200 mm NaCl. In leaf tissues, a total of 176 protein spots showed significant changes (P < 0.05), of which 104 spots were induced and 72 spots suppressed. Salt-induced proteins are associated with the following pathways: photosynthesis, carbohydrate metabolism, glyoxylate shunt, glycine cleavage system, branched-chain amino acid biosynthesis, protein folding, defense and cellular protection, signal transduction, ion transport, and antioxidant activities. Suppressed proteins belong to the following categories: oxidative phosphorylation pathway, photorespiration and protein translational machinery, oxidative stress, and ATPases. In root tissues, 106 protein spots changed significantly (P < 0.05) after the salt treatment, 63 spots were induced, and 43 suppressed by salt treatment. Salt-induced proteins are associated with the following functional pathways: regeneration of S-adenosyl methionine, protein folding, selective ion transport, antioxidants and defense mechanism, signal transduction and gene expression regulation, and branched-chain amino acid synthesis. Salt-suppressed proteins are receptor kinase proteins, peroxidases and germin-like proteins, malate dehydrogenase, and glycine dehydrogenase. In this study, different members of proteins were identified from leaf and root tissues after plants were subjected to salt treatment. These proteins represent tissue-specific changes in salt-induced proteomes. When protein expression was compared in the context of metabolic pathways, the branched-chain amino acid biosynthesis, glucose catabolism toward reducing cellular glucose level, and the antioxidant, detoxification, and selective ion uptake and transport were induced in both root and leaf tissues. These changes appear to be associated with salt tolerance in the whole plant.

Comparative transcriptome study of the leaf and root tissues of Catharanthus roseus is a prerequisite for causing any favorable tissue-specific change in the secondary metabolism of this species. This study was aimed at comparative analysis of the leaf and root cDNAs in C. roseus, using a cDNA-AFLP approach. Using 64 primer combinations (EcoRI and MseI), a total of 784 distinct transcriptionally-defined fragments (TDFs) could be detected in the root and leaf tissue transcript populations. The leaf tissue yielded a larger number of TDFs than the root tissue (556 versus 464), indicating a greater variety of expressing genes in the leaf. The leaf-specific TDFs (320) outnumbered the root-specific TDFs (228), indicating a higher number of leaf-specific functions and the relative complexity of the leaf tissue vis-à-vis the root tissue. Among the 236 TDFs that were detected in both types of tissues, 42 had nearly equal expression levels in both the tissues (L=R). Common TDFs having higher expression levels in the leaf (L>R; 124) outnumbered those having higher expression levels in the root (L<R; 70), which again reinforced the predominance of the leaf transcriptome over the root transcriptome.

Angelica glauca Edgew, which is an endangered medicinal and aromatic herb, is a rich source of numerous industrially important bioactive metabolites, including terpenoids, phenolics, and phthalides. Nevertheless, genomic interventions for the sustainable utilization and restoration of its genetic resources are greatly offset due to the scarcity of the genomic resources and key regulators of the underlying specialized metabolism. To unravel the global atlas of the specialized metabolism, the first spatial transcriptome sequencing of the leaf, stem, and root generated 109 million high-quality paired-end reads, assembled de novo into 81,162 unigenes, which exhibit a 61.53% significant homology with the six public protein databases. The organ-specific clustering grouped 1136 differentially expressed unigenes into four subclusters differentially enriched in the leaf, stem, and root tissues. The prediction of the transcriptional-interactome network by integrating enriched gene ontology (GO) and the KEGG metabolic pathways identified the key regulatory unigenes that correspond to terpenoid, flavonoid, and carotenoid biosynthesis in the leaf tissue, followed by the stem and root tissues. Furthermore, the stem and root-specific significant enrichments of phenylalanine ammonia lyase (PAL), cinnamate-4-hydroxylase (C4H), and caffeic acid 3-O-methyltransferase (COMT) indicate that phenylalanine mediated the ferulic acid biosynthesis in the stem and root. However, the root-specific expressions of NADPH-dependent alkenal/one oxidoreductase (NADPH-AOR), S-adenosyl-L-methionine-dependent methyltransferases (SDMs), polyketide cyclase (PKC), and CYP72A15 suggest the “root” as the primary site of phthalide biosynthesis. Additionally, the GC-MS and UPLC analyses corresponded to the organ-specific gene expressions, with higher contents of limonene and phthalide compounds in the roots, while there was a higher accumulation of ferulic acid in the stem, followed by in the root and leaf tissues. The first comprehensive genomic resource with an array of candidate genes of the key metabolic pathways can be potentially utilized for the targeted upscaling of aromatic and pharmaceutically important bioactive metabolites. This will also expedite genomic-assisted conservation and breeding strategies for the revival of the endangered A. glauca.

Rabbit antiserum was raised against NADH-glutamate dehydrogenase (GDH) isoenzyme 1, purified from leaves of Vitis vinifera L. cv Soultanina and its specificity was tested. This antiserum was used for immunocharacterization of the GDH from leaf, shoot, and root tissues. The antiserum recognized the seven isoenzymes of NADH-GDH and precipitated all the enzyme activity from the three tissues tested. Western blot following SDS-PAGE revealed the same protein band for the three tissues, with a molecular mass of 42.5 kilodaltons corresponding to NADH-GDH subunit. Results, based on the immunological studies, revealed that NADH-GDH from leaf, shoot, and root tissues are closely related proteins. Furthermore, addition of ammonium ions to the culture medium of in vitro grown explants resulted in a significant increase in NADH-GDH activity in root, shoot, and leaf tissues.

Unique responses of respiration, growth, and non-structural carbohydrate storage in sink tissue of conifer seedlings to an elevation gradient at timberline

Sodium bicarbonate stress caused by NaHCO3 is one of the most severe abiotic stresses affecting agricultural production worldwide. However, little attention has been given to the molecular mechanisms underlying plant responses to sodium bicarbonate stress. To understand phosphorylation events in signaling pathways triggered by sodium bicarbonate stress, TMT-labeling-based quantitative phosphoproteomic analyses were performed on soybean leaf and root tissues under 50 mM NaHCO3 treatment. In the present study, a total of 7856 phosphopeptides were identified from cultivated soybeans (Glycine max L. Merr.), representing 3468 phosphoprotein groups, in which 2427 phosphoprotein groups were newly identified. These phosphoprotein groups contained 6326 unique high-probability phosphosites (UHPs), of which 77.2% were newly identified, increasing the current soybean phosphosite database size by 43.4%. Among the phosphopeptides found in this study, we determined 67 phosphopeptides (representing 63 phosphoprotein groups) from leaf tissue and 554 phosphopeptides (representing 487 phosphoprotein groups) from root tissue that showed significant changes in phosphorylation levels under sodium bicarbonate stress (fold change >1.2 or <0.83, respectively; p < 0.05). Localization prediction showed that most phosphoproteins localized in the nucleus for both leaf and root tissues. GO and KEGG enrichment analyses showed quite different enriched functional terms between leaf and root tissues, and more pathways were enriched in the root tissue than in the leaf tissue. Moreover, a total of 53 different protein kinases and 7 protein phosphatases were identified from the differentially expressed phosphoproteins (DEPs). A protein kinase/phosphatase interactor analysis showed that the interacting proteins were mainly involved in/with transporters/membrane trafficking, transcriptional level regulation, protein level regulation, signaling/stress response, and miscellaneous functions. The results presented in this study reveal insights into the function of post-translational modification in plant responses to sodium bicarbonate stress.

We used 14C tracers to determine photosynthate distribution in cherrybark oak (Quercus pagoda Raf.) seedling sprouts following release from competing mid-story vegetation. Fall acquisition of labeled photosynthates by seedlings followed expected source-sink patterns, with root and basal stem tissues serving as the primary sinks. Four months after the seedlings had been labeled with 14C, they were clipped to induce sprouting. First-flush stem and leaf tissues of the resulting seedling sprouts were the primary sinks for labeled photosynthates stored in root tissues. Second-flush stem and leaf tissues, and first-flush stem and leaf tissues the following growing season, were not primary sinks for labeled photosynthates stored in root tissues despite the high radioactivity in root tissues. Root tissues appeared to deposit photosynthates in a layering process whereby the last photosynthates stored in new xylem were the first to be depleted during the initiation of a growth flush the following spring. There were more labeled photosynthates in roots of released seedling sprouts compared with non-released seedling sprouts, indicating increased vigor of released seedling sprouts in response to greater light availability. In contrast, stem and source leaf tissues of non-released seedling sprouts contained greater percentages of labeled photosynthates compared with released seedling sprouts, indicating either greater sink strength or poorly developed xylem and phloem pathways that created inefficiencies in distribution to root tissues. The 14C distribution coefficients confirmed the distribution patterns and provided additional information on the important sinks in released and non-released cherrybark oak seedling sprouts.

The mangrove ecosystem is one of the vegetation that has a role as carbon mitigation in coastal areas, especially in port activity areas that can produce large amounts of carbon, such as in Lembar Harbor, Lembar Village, West Lombok Regency. The purpose of this study was to analyze the carbon content in the root and leaf tissue contained in each type of mangrove in the Lembar Harbor Area, Lembar Village, West Lombok Regency. This type of research is descriptive quantitative, with purposive random sampling method, which starts with taking root and leaf samples on each different mangrove species, and testing is carried out based on the Walkley &amp; Black method to obtain tissue carbon content. Based on the results of the study, found 8 (eight) families consisting of 11 species, including: Avicennia lanata, Avicennia marina, Lumnitzera racemosa, Bruguiera gymnorrhiza, Rhizophora stylosa, Ceriops decandra, Scyphiphora hydrophyllaceae, Excoecaria agallocha, Thespesia populnea, Xylocensis, and Ipome pescaprae. The condition of the environmental parameters of the mangrove ecosystem in Lembar Village is still in good condition, in accordance with the quality standards of water health quality, Decree of the State Minister of the Environment Number 51 of 2004 concerning sea water quality standards for biota. The average organic carbon content of root tissue was 43.47 ± 3.10 %C and leaves was 43.87 ± 3.66 %C. The highest organic carbon content in root tissue was found in Xylocarpus moluccensis (47.46 %C), and the lowest was in Ipomea pescaprae (41.49 %C), while the highest organic carbon content in leaf tissue was in Bruguiera gymnorrhiza (50.60 %C), and the lowest was Avicennia lanata (38.99 %C). Based on Tukey's further test that the value of organic content stored in the root and leaf tissue of mangroves was not significantly different (&gt; 0.05) with a statistical test value of 0.76.

The development of salt-tolerant rice has become urgent due to climate change and rising global rice consumption. A large-scale analysis using different but related platforms has become imperative to filter out candidate genes responsible for salinity tolerance and salinity stress-responsive pathways. Such genes can be used to find prospective candidate salt resistance genes in donor rice genotypes and transfer them to high-yielding rice varieties. We performed a meta-analysis to screen out candidate genes using stress-related three microarray and one RNASeq datasets from NCBI. As different genotypes of rice and different salinity stress conditions were considered in our analysis, the sensitivity of the results is expected to be multi-fold higher. Our analysis revealed the differentially expressed genes (DEGs) OsbZIP52 and OsLTP2.5 to be common between leaf and root tissues. These genes were further compared with those of the wild halophytic rice Oryza coarctata expression data in stress conditions to understand the significance of these genes. The OsbZIP52 gene homolog of Oryza coarctata was the only one found to be differentially expressed. The expression level of OsbZIP52 was quantified using RT-qPCR and observed downregulated expression in salt stress in root and leaf tissues of four rice cultivars (2 salt-tolerant and 2 salt-sensitive). Promoter and motif analysis revealed a high number of variations in promoter and motif regions of the gene in IR29 salt-sensitive rice. Expression correlation analysis and Gene Ontology study suggested that OsbZIP52 interacts with genes that are engaged in stress response and participate in stress-responsive pathways. Collectively this study increases our understanding of the differential gene expression in various stress conditions in root and leaf tissues. It also helped identify a critical regulatory transcription factor in assisting the plant in combating salinity stress.