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Nervonic acid (C24:1) is a very-long-chain fatty acid that plays an imperative role in human brain development and other health benefits. In plants, 3-ketoacyl-CoA synthase (KCS) is the key rate-limiting enzyme for C24:1 biosynthesis. Xanthoceras sorbifolium is a valuable oil-producing economic woody species with abundant C24:1 in seed oils, but the key KCS gene responsible for C24:1 accumulation remains unknown. In this work, a correlation analysis between the transcript profiles of KCS and dynamic change of C24:1 content in developing seeds of X. sorbifolium were conducted to screen out three members of KCS, namely XsKCS4, XsKCS7 and XsKCS8, potentially involved in C24:1 biosynthesis. Of which, the XsKCS7 was highly expressed in developing seeds, while XsKCS4 and XsKCS8 displayed the highest expression in fruits and flowers, respectively. Overexpression of XsKCS4, XsKCS7 and XsKCS8 in yeast Saccharomyces cerevisiae and plant Arabidopsis thaliana indicated that only XsKCS7 possessed the ability to facilitate the biosynthesis of C24:1. These findings collectively suggested that XsKCS7 played a crucial role in specific regulation of C24:1 biosynthesis in X. sorbifolium seeds., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Present study assessed the growth of two plant species and ion uptake by them grown on different proportion of industrial solid waste and garden soil. The industrial waste having high concentration of chemicals were used with garden soil at different proportion i.e. 0% (T0), 5% (T1), 10% (T2), 15% (T3) and 20% (T4). Two species namely Conocarpus erectus (alien plant) and Dodonaea viscosa (indigenous) were used as test plants in pot study. Different parameters including growth, physiology, and anatomy of plants and concentration of cations (Na + , K + , Ca 2+ , and Mg 2+ ) in the plant shoot and root were measured at different time duration (initial, 1 st , 2 nd , 3 rd and 4 th month). The key objective of the study was to use these plants to establish their plantations on the barren lands where industrial solid wastes were being disposed of. C. erectus showed better growth than D. viscosa, as well as more uptake of ions. A significant increase in plant growth was observed in fourth month in T1, where plant height reached 24.5% and 46% for C. erectus and D. viscosa, respectively. At harvest, in C. erectus, no significant difference in the fresh (65-78 g) and dry weight (24-30 g) of the shoot was observed across treatments compared to the control. In D. viscosa, at the time of harvest, the fresh and dry weights of the root and shoot showed a strong, significantly decreasing pattern across T1, T2, and T3, leading to the death of the plant at T3 and T4. Further, optimum ratio of waste soil to garden soil was found as 10:90 and 20:80 to establish the plantations of D. viscosa and C. erectus, respectively in areas where such solid waste from industries are disposed. Findings can be used for the restoration of such solid waste for the sustainable management of industrial areas and their associated ecosystems., (© 2024. The Author(s).)

Somatic embryogenesis (SE), like zygotic embryo development, is a progressive process. Early SE is the beginning of a switch from a somatic to an embryogenic state and is an important stage for initiating chromatin reprogramming of SE. Previous studies suggest that changes in chromatin accessibility occur during early SE, although information on the 3D structure of chromatin is not yet available. Here, we present a chromosome-level genome assembly of longan (Dimocarpus longan) using PacBio combined with high-through chromosome conformation capture scaffolding, which resulted in a 446 Mb genome assembly anchored onto 15 scaffolds. During early SE, chromatin was concentrated and then decondensed, and a large number of long terminal repeat retrotransposons (LTR-RTs) were enriched in the local chromatin interaction region, suggesting LTR-RTs were involved in chromatin reorganization. Early SE was accompanied by the transformation from A to B compartments, and the interactions between B compartments were enhanced. Results from chromatin accessibility, monomethylation of histone H3 at lysine 4 (H3K4me1) modification, and transcription analyses further revealed a gene regulatory network for cell wall thickening during SE. Particularly, we found that the H3K4me1 differential peak binding motif showed abnormal activation of ethylene response factor transcription factors and participation in SE. The chromosome-level genomic and multiomics analyses revealed the 3D conformation of chromatin during early SE, providing insight into the molecular mechanisms underlying cell wall thickening and the potential regulatory networks of TFs during early SE in D. longan. These results provide additional clues for revealing the molecular mechanisms of plant SE., Competing Interests: Conflict of interest statement. None declared., (© American Society of Plant Biologists 2023. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Core cell cycle genes (CCCs) are essential regulators of cell cycle operation. In this study, a total of 69 CCCs family members, including 37 CYCs, 20 CDKs, five E2F/DPs, three KRPs, two RBs, one CKS and one Wee1, were identified from the longan genome. Phylogenetic and motifs analysis showed the evolutionary conservation of CCCs. Transcriptome dataset showed that CCCs had various expression patterns during longan early somatic embryogenesis (SE). Either CKS or CYCD3;2 silencing increased the expression of RB-E2F pathway genes, and the silencing of CYCD3;2 might induce the process of apoptosis in longan embryogenic callus (EC) cells. In addition, The qRT-PCR results showed that the expression levels of CDKG2, CYCD3;2, CYCT1;2, CKS and KRP1 were elevated by ABA, 2,4-D and PEG4000 treatments, while CDKG2 and CYCT1;2 were inhibited by NaCl treatment. In conclusion, our study provided valuable information for understanding the characterization and biological functions of longan CCCs., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The process of phloem unloading and post-unloading transport of photoassimilate is critical to crop output. Xanthoceras sorbifolia is a woody oil species with great biomass energy prospects in China; however, underproduction of seeds seriously restricts its development. Here, our cytological studies by ultrastructural observation revealed that the sieve element-companion cell complex in carpellary bundle was symplasmically interconnected with surrounding parenchyma cells at the early and late fruit developmental stages, whereas it was symplasmically isolated at middle stage. Consistently, real-time imaging showed that fluorescent tracer 6(5)carboxyfluorescein was confined to phloem strands at middle stage but released into surrounding parenchymal cells at early and late stages. Enzymatic assay showed that sucrose synthase act as the key enzyme catalyzing the progress of Suc degradation post-unloading pathway whether in pericarp or in seed, while vacuolar acid invertase and neutral invertase play compensation roles in sucrose decomposition. Sugar transporter XsSWEET10 had a high expression profile in fruit, especially at middle stage. XsSWEET10 is a plasma membrane-localized protein and heterologous expression in SUC2-deficient yeast strain SUSY7/ura3 confirmed its ability to uptake sucrose. These findings approved the transition from symplasmic to apoplasmic phloem unloading in Xanthoceras sorbifolia fruit and XsSWEET10 as a key candidate in sugar transport., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Rambutan is a popular tropical fruit known for its exotic appearance, has long flexible spines on shells, extraordinary aril growth, desirable nutrition, and a favorable taste. The genome of an elite rambutan cultivar Baoyan 7 was assembled into 328 Mb in 16 pseudo-chromosomes. Comparative genomics analysis between rambutan and lychee revealed that rambutan chromosomes 8 and 12 are collinear with lychee chromosome 1, which resulted in a chromosome fission event in rambutan (n = 16) or a fusion event in lychee (n = 15) after their divergence from a common ancestor 15.7 million years ago. Root development genes played a crucial role in spine development, such as endoplasmic reticulum pathway genes, jasmonic acid response genes, vascular bundle development genes, and K + transport genes. Aril development was regulated by D-class genes (STK and SHP1), plant hormone and phenylpropanoid biosynthesis genes, and sugar metabolism genes. The lower rate of male sterility of hermaphroditic flowers appears to be regulated by MYB24. Population genomic analyses revealed genes in selective sweeps during domestication that are related to fruit morphology and environment stress response. These findings enhance our understanding of spine and aril development and provide genomic resources for rambutan improvement., (© 2021 Society for Experimental Biology and John Wiley & Sons Ltd. This article has been contributed to by US Government employees and their work is in the public domain in the USA.)

Background: Yellowhorn (Xanthoceras sorbifolium), an endemic woody oil-bearing tree, has become economically important and is widely cultivated in northern China for bioactive oil production. However, the regulatory mechanisms of seed development and lipid biosynthesis affecting oil production in yellowhorn are still elusive. MicroRNAs (miRNAs) play crucial roles in diverse aspects of biological and metabolic processes in seeds, especially in seed development and lipid metabolism. It is still unknown how the miRNAs regulate the seed development and lipid biosynthesis in yellowhorn., Results: Here, based on investigations of differences in the seed growth tendency and embryo oil content between high-oil-content and low-oil-content lines, we constructed small RNA libraries from yellowhorn embryos at four seed development stages of the two lines and then profiled small RNA expression using high-throughput sequencing. A total of 249 known miRNAs from 46 families and 88 novel miRNAs were identified. Furthermore, by pairwise comparisons among the four seed development stages in each line, we found that 64 miRNAs (53 known and 11 novel miRNAs) were differentially expressed in the two lines. Across the two lines, 15, 11, 10, and 7 differentially expressed miRNAs were detected at 40, 54, 68, and 81 days after anthesis, respectively. Bioinformatic analysis was used to predict a total of 2654 target genes for 141 differentially expressed miRNAs (120 known and 21 novel miRNAs). Most of these genes were involved in the fatty acid biosynthetic process, regulation of transcription, nucleus, and response to auxin. Using quantitative real-time PCR and an integrated analysis of miRNA and mRNA expression, miRNA-target regulatory modules that may be involved in yellowhorn seed size, weight, and lipid biosynthesis were identified, such as miR172b-ARF2 (auxin response factor 2), miR7760-p3_1-AGL61 (AGAMOUS-LIKE 61), miR319p_1-FAD2-2 (omega-6 fatty acid desaturase 2-2), miR5647-p3_1-DGAT1 (diacylglycerol acyltransferase 1), and miR7760-p5_1-MED15A (Mediator subunit 15a)., Conclusions: This study provides new insights into the important regulatory roles of miRNAs in the seed development and lipid biosynthesis in yellowhorn. Our results will be valuable for dissecting the post-transcriptional and transcriptional regulation of seed development and lipid biosynthesis, as well as improving yellowhorn in northern China., (© 2021. The Author(s).)

Paullinieae are a diverse group of tropical and subtropical climbing plants that belong to the soapberry family (Sapindaceae). The six genera in this tribe make up approximately one-quarter of the species in the family, but a sparse fossil record limits our understanding of their diversification. Here, we provide the first description of anatomically preserved fossils of Paullinieae and we re-evaluate other macrofossils that have been attributed to the tribe. We identified permineralized fossil roots in collections from the lower Miocene Cucaracha Formation where it was exposed along the Culebra Cut of the Panama Canal. We prepared the fossils using the cellulose acetate peel technique and compared the anatomy with that of extant Paullinieae. The fossil roots preserve a combination of characters found only in Paullinieae, including peripheral secondary vascular strands, vessel dimorphism, alternate intervessel pitting with coalescent apertures, heterocellular rays, and axial parenchyma strands of 2-4 cells, often with prismatic crystals. We also searched the paleontological literature for other occurrences of the tribe. We re-evaluated leaf fossils from western North America that have been assigned to extant genera in the tribe by comparing their morphology to herbarium specimens and cleared leaves. The fossil leaves that were assigned to Cardiospermum and Serjania from the Paleogene of western North America are likely Sapindaceae; however, they lack diagnostic characters necessary for inclusion in Paullinieae and should be excluded from those genera. Therefore, the fossils described here as Ampelorhiza heteroxylon gen. et sp. nov. are the oldest macrofossil evidence of Paullinieae. They provide direct evidence of the development of a vascular cambial variant associated with the climbing habit in Sapindaceae and provide strong evidence of the diversification of crown-group Paullinieae in the tropics by 18.5-19 million years ago., Competing Interests: The authors have declared that no competing interests exist.

Yellow horn (Xanthoceras sorbifolia) is an oil-rich woody plant cultivated for bio-energy production in China. Soil saline-alkalization is a prominent agricultural-related environmental problem limiting plant growth and productivity. In this study, we performed comparative physiological and transcriptomic analyses to examine the mechanisms of X. sorbifolia seedling responding to salt and alkaline-salt stress. With the exception of chlorophyll content, physiological experiments revealed significant increases in all assessed indices in response to salt and saline-alkali treatments. Notably, compared with salt stress, we observed more pronounced changes in electrolyte leakage (EL) and malondialdehyde (MDA) levels in response to saline-alkali stress, which may contribute to the greater toxicity of saline-alkali soils. In total, 3,087 and 2,715 genes were differentially expressed in response to salt and saline-alkali treatments, respectively, among which carbon metabolism, biosynthesis of amino acids, starch and sucrose metabolism, and reactive oxygen species signaling networks were extensively enriched, and transcription factor families of bHLH, C2H2, bZIP, NAC, and ERF were transcriptionally activated. Moreover, relative to salt stress, saline-alkali stress activated more significant upregulation of genes related to H+ transport, indicating that regulation of intracellular pH may play an important role in coping with saline-alkali stress. These findings provide new insights for investigating the physiological changes and molecular mechanisms underlying the responses of X. sorbifolia to salt and saline-alkali stress., Competing Interests: The authors have declared that no competing interests exist.

Stable carbon and oxygen isotope ratios of raw pollen sampled from nine abundant tree species growing in natural habitats of central and northern Europe were investigated to understand the intra- and inter-specific variability of pollen-isotope values. All species yielded specific δ13Cpollen and δ18Opollen values and patterns, which can be ascribed to their physiology and habitat preferences. Broad-leaved trees flowering early in the year before leaf proliferation (Alnus glutinosa and Corylus avellana) exhibited on average 2.6‰ lower δ13Cpollen and 3.1‰ lower δ18Opollen values than broad-leaved and coniferous trees flowering during mid and late spring (Acer pseudoplatanus, Betula pendula, Carpinus betulus, Fagus sylvatica, Picea abies, Pinus sylvestris and Quercus robur). Mean species-specific δ13Cpollen values did not change markedly over time, whereas δ18Opollen values of two consecutive years were often statistically distinct. An intra-annual analysis of B. pendula and P. sylvestris pollen revealed increasing δ18Opollen values during the final weeks of pollen development. However, the δ13Cpollen values remained consistent throughout the pollen-maturation process. Detailed intra-individual analysis yielded circumferential and height-dependent variations within carbon and oxygen pollen-isotopes and the sampling position on a tree accounted for differences of up to 3.5‰ for δ13Cpollen and 2.1‰ for δ18Opollen. A comparison of isotope ranges from different geographic settings revealed gradients between maritime and continental as well as between high and low altitudinal study sites. The results of stepwise regression analysis demonstrated, that carbon and oxygen pollen-isotopes also reflect local non-climate environmental conditions. A detailed understanding of isotope patterns and ranges in modern pollen is necessary to enhance the accuracy of palaeoclimate investigations on δ13C and δ18O of fossil pollen. Furthermore, pollen-isotope values are species-specific and the analysis of species growing during different phenophases may be valuable for palaeoweather reconstructions of different seasons., Competing Interests: The authors have declared that no competing interests exist.

Background: The APETALA2/ethylene responsive factor (AP2/ERF) superfamily members are transcription factors that regulate diverse developmental processes and stress responses in plants. They have been identified in many plants. However, little is known about the AP2/ERF superfamily in longan (Dimocarpus longan Lour.), which is an important tropical/subtropical evergreen fruit tree that produces a variety of bioactive compounds with rich nutritional and medicinal value. We conducted a genome-wide analysis of the AP2/ERF superfamily and its roles in somatic embryogenesis (SE) and developmental processes in longan., Results: A genome-wide survey of the AP2/ERF superfamily was carried out to discover its evolution and function in longan. We identified 125 longan AP2/ERF genes and classified them into the ERF (101 members), AP2 (19 members), RAV (four members) families, and one Soloist. The AP2 and Soloist genes contained one to ten introns, whereas 87 genes in the ERF and RAV families had no introns. Hormone signaling molecules such as methyl jasmonate (MeJA), abscisic acid (ABA), gibberellin, auxin, and salicylic acid (SA), and stress response cis-acting element low-temperature (55) and defense (49) boxes also were identified. We detected diverse single nucleotide polymorphisms (SNPs) between the 'Hong He Zi' (HHZ) and 'SI JI MI' (SJM) cultivars. The number of insertions and deletions (InDels) was far fewer than SNPs. The AP2 family members exhibited more alternative splicing (AS) events in different developmental processes of longan than members of the other families. Expression pattern analysis revealed that some AP2/ERF members regulated early SE and developmental processes in longan seed, root, and flower, and responded to exogenous hormones such as MeJA, SA, and ABA, and 2,4-D, a synthetic auxin. Protein interaction predictions indicated that the Baby Boom (BBM) transcription factor, which was up-regulated at the transcriptional level in early SE, may interact with the LALF/AGL15 network., Conclusions: The comprehensive analysis of molecular evolution and expression patterns suggested that the AP2/ERF superfamily may plays an important role in longan, especially in early SE, and in seed, root, flower, and young fruit. This systematic analysis provides a foundation for further functional characterization of the AP2/ERF superfamily with the aim of longan improvement.

Background: Somatic embryogenesis (SE) is a process of somatic cells that dedifferentiate to totipotent embryonic stem cells and generate embryos in vitro. Longan SE has been established and wildly used as model system for studying embryogenesis in woody plants, SE-related genes had been characterized. In spite of that, a comprehensive overview of SE at a molecular level is still absent. To understand the molecular mechanisms during longan SE, we examined the transcriptome changes by using Illumina HiSeq from the four distinct developmental stages, including non-embryogenic callus (NEC), embryogenic callus (EC), incomplete compact pro-embryogenic cultures (ICpEC), globular embryos (GE)., Results: RNA-seq of the four samples generated a total of 243.78 million high quality reads, approximately 81.5% of the data were mapped to longan genome. The cDNA libraries of NEC, EC, ICpEC and GE, generated 22,743, 19,745, 21,144, 21,102 expressed transcripts, 1935, 1710, 1816, 1732 novel transcripts, 2645, 366, 505, 588 unique genes, respectively. Comparative transcriptome analysis showed that a total of 10,642, 4180, 5846 and 1785 genes were differentially expressed in the pairwise comparisons of NEC_vs_EC, EC_vs_ICpEC, EC_vs_GE, ICpEC_vs_GE, respectively. Among them, plant hormones signalling related genes were significantly enriched, especially the auxin and cytokinin signalling components. The transcripts of flavonoid biosynthesis related genes were mainly expressed in NEC, while fatty acid biosynthesis related genes mainly accumulated in early SE. In addition, the extracelluar protein encoding genes LTP, CHI, GLP, AGP, EP1 were related to longan SE. Combined with the FPKM value of longan nine tissues transcription, 27 SE specific or preferential genes (LEC1, LEC1-like, PDF1.3, GH3.6, AGL80, PIN1, BBM, WOX9, WOX2, ABI3, et al.) and 28 NEC preferential genes (LEA5, CNOT3, DC2.15, PR1-1, NsLTP2, DIR1, PIP1, PIP2.1, TIP2-1, POD-P7 and POD5 et al.) were characterized as molecular markers for longan early SE. qRT-PCR validation of SE-related genes showed a high correlation between RNA-seq and qRT-PCR data., Conclusion: This study provides new insights into the role of the transcriptome during early SE in longan. Differentially expressed genes reveal that plant hormones signalling, flavonoid and fatty acid biosynthesis, and extracelluar protein related genes were involved in longan early SE. It could serve as a valuable platform resource for further functional studies addressing embryogenesis in woody plants.

Members of the bZIP transcription factor family play crucial roles in the regulation of plant development, biosynthesis of secondary metabolites, and response to abiotic and biotic stresses. To date, multiple bZIPs have been identified and investigated in numerous plant species. However, few studies have characterized bZIPs from Dimocarpus longan Lour. In this study, nine bZIPs from D. longan were identified from RNA-Seq data and further verified using the NCBI conserved domain search tool and Pfam database. Bioinformatics tools were used to systematically analyse the physicochemical properties, protein structures, multiple sequence alignment, motif compositions, evolutionary relationships, secondary structures, subcellular localization, phosphorylation sites, signal peptides, GO annotations and protein-protein interactions of the DlbZIPs . The expression patterns of the nine DlbZIPs were evaluated by qRT-PCR in roots and leaves and in response to varying durations of a 38°C heat treatment. DlbZIP3 , DlbZIP5 , DlbZIP6 and DlbZIP7 were differentially expressed between root and leaf tissues. All nine DlbZIPs responded to heat treatment in both roots and leaves, but their specific expression levels differed. DlbZIP4 and DlbZIP8 were highly expressed in roots after heat treatment, whereas DlbZIP1 and DlbZIP5 were highly expressed in leaves after heat treatment. These findings lay a foundation for increasing active secondary metabolite content and improving abiotic stress tolerance in D. longan using transgenic technology.

Background: Longan (Dimocarpus longan Lour.) is an important fruit tree in the subtropical regions of Southeast Asia and Australia. Among the factors affecting D. longan fruit yield, the difficulty and instability of blossoming is one of the most challenging issues. Perpetual flowering (PF) is a crucial trait for fruit trees and is directly linked to production potential. Therefore, studying the molecular regulatory mechanism of longan PF traits is crucial for understanding and solving problems related to flowering. In this study, comparative transcriptome analysis was performed using two longan cultivars that display opposite flowering phenotypes during floral induction., Results: We obtained 853.72 M clean reads comprising 125.08 Gb. After comparing these data with the longan genome, 27,266 known genes and 1913 new genes were detected. Significant differences in gene expression were observed between the two genotypes, with 6150 and 6202 differentially expressed genes (DEGs) for 'SJ' and 'SX', respectively. The transcriptional landscape of floral transition at the early stage was very different in these two longan genotypes with respect to key hormones, circadian rhythm, sugar metabolism, and transcription factors. Almost all flowering-related DEGs identified are involved in photoperiod and circadian clock pathways, such as CONSTANS-like (COL), two-component response regulator-like (APRRs), gigantea (GI), and early flowering (EFL). In addition, the leafy (LFY) gene, which is the central floral meristem identity gene, may inhibit PF formation in 'SJ'., Conclusion: This study provides a platform for understanding the molecular mechanisms responsible for changes between PF and seasonal flowering (SF) longan genotypes and may benefit studies on PF trait mechanisms of evergreen fruit trees.

This study investigated the changes in metabolisms of membrane lipids and phenolics caused by Phomopsis longanae Chi infection in association with pericarp browning and fruit disease occurrence of postharvest longans. Compared with the uninoculated-longans, the longans inoculated by P. longanae exhibited higher cellular membrane permeability; higher PLD, lipase, and LOX activities; and higher levels of saturated fatty acids (SFAs) and phosphatidic acid but lower levels of phosphatidylinositol, phosphatidylcholine, and unsaturated fatty acids (USFAs). Additionally, the longans inoculated by P. longanae showed higher activities of POD and PPO but a lower amount of total phenolics. These findings suggested that infection of P. longanae enhanced activities of PLD-, lipase-, and LOX- stimulated degradations of membrane lipids and USFAs, which destroyed the integrity of the cell membrane structure, resulting in enzymatic browning by contact of phenolics with POD and PPO, and resulting in reduction of resistance to pathogen infection and accordingly accelerated disease occurrence of postharvest longan fruit.

Yellow horn ( Xanthoceras sorbifolium Bunge) is an endemic oil-rich shrub that has been widely cultivated in northern China for bioactive oil production. However, little is known regarding the molecular mechanisms that contribute to oil content in yellow horn. Herein, we measured the oil contents of high- and low-oil yellow horn embryo tissues at four developmental stages and investigated the global gene expression profiles through RNA-seq. The results found that at 40, 54, 68, and 81 days after anthesis, a total of 762, 664, 599, and 124 genes, respectively, were significantly differentially expressed between the high- and low-oil lines. Gene ontology (GO) enrichment analysis revealed some critical GO terms related to oil accumulation, including acyl-[acyl-carrier-protein] desaturase activity, pyruvate kinase activity, acetyl-CoA carboxylase activity, and seed oil body biogenesis. The identified differentially expressed genes also included several transcription factors, such as, AP2-EREBP family members, B3 domain proteins and C2C2-Dof proteins. Several genes involved in fatty acid (FA) biosynthesis, glycolysis/gluconeogenesis, and pyruvate metabolism were also up-regulated in the high-oil line at different developmental stages. Our findings indicate that the higher oil accumulation in high-oil yellow horn could be mostly driven by increased FA biosynthesis and carbon supply, i.e. a source effect.

Koelreuteria paniculata were cultivated in nutrient solution with different concentrations of Cd (0, 50, 150, 250 and 500 µM) and sampled after 90 days. The resistance, translocation, accumulation and stress responses in Koelreuteria paniculata were investigated by hydroponic experiments. The results showed that Koelreuteria paniculata is an efficient Cd excluder that can tolerate high concentrations of Cd (up to 150-250 µM of Cd). The concentration of Cd never exceeds 5 ppm in leaves and 10 ppm in roots. The high concentration of Cd (≥ 250 µM) had a toxic effect on K. paniculata and significantly restricted the plant growth. The accumulation ability of Cd by different plant tissues followed the sequence of roots > leaves > stems. The bioconcentration factors and translocation factors both were less than 1. Cd has the highest content in the cell wall and is migrated to soluble fractions and organelles at high concentrations. Undissolved Cd phosphate, pectates and protein-bound Cd were the predominant forms. The low concentration of Cd (≤150 µM) promoted the synthesis of soluble proteins, AsA and GSH, while high concentration of Cd clearly inhibited the physiological and biochemical process, caused membrane lipid peroxidation and severe membrane damages, and increased MDA and H 2 O 2 contents. POD, CAT and SOD exhibited positive and effective responses to low concentration Cd stress, but could not remove the toxicity caused by high concentration Cd stress. The content of IAA, GA and ZT decreased and ABA content was significantly increased under high-concentration Cd stress., (Copyright © 2018. Published by Elsevier Inc.)

Ubiquitin-conjugating enzymes (E2s or UBC enzymes) play vital roles in plant development and combat various biotic and abiotic stresses. Longan ( Dimocarpus longan Lour.) is an important fruit tree in the subtropical region of Southeast Asia and Australia; however the characteristics of the UBC gene family in longan remain unknown. In this study, 40 D. longan UBC genes ( DlUBCs ), which were classified into 15 groups, were identified in the longan genome. An RNA-seq based analysis showed that DlUBCs showed distinct expression in nine longan tissues. Genome-wide RNA-seq and qRT-PCR based gene expression analysis revealed that 11 DlUBCs were up- or down-regualted in the cultivar "Sijimi" (SJ), suggesting that these genes may be important for flower induction. Finally, qRT-PCR analysis showed that the mRNA levels of 13 DlUBCs under SA (salicylic acid) treatment, seven under methyl jasmonate (MeJA) treatment, 27 under heat treatment, and 16 under cold treatment were up- or down-regulated, respectively. These results indicated that the DlUBCs may play important roles in responses to abiotic stresses. Taken together, our results provide a comprehensive insight into the organization, phylogeny, and expression patterns of the longan UBC genes, and therefore contribute to the greater understanding of their biological roles in longan., Competing Interests: The authors declare no conflict of interest.

Paullinia cupana Kunth var. sorbilis (Mart.) Ducke, the cultivated guarana plant, is native to the Amazon and has been valued for its medicinal, stimulant and energetic properties for centuries. The seeds are the main commercial product of the plant and the source of high amounts of purine alkaloids (caffeine and theobromine) and polyphenols (flavonoids, catechins, and tannins). Proteins involved in the development and maturation of guarana fruits in its native habitat are interesting issues for proteomics. This study presents the proteomic profile of the seed and pericarp of healthy guarana in different maturation stages. Protein contents were higher in the mature seed compared to other stages due to the accumulation of storage proteins - 11S globulins. Proteins selected for identification by mass spectrometry are mostly related to stress responses and defense and this is not unexpected for fast growing and differentiating reproductive tissues.

The abundance of shrubs has increased throughout Earth's arid lands. This 'shrub encroachment' has been linked to livestock grazing, fire-suppression and elevated atmospheric CO 2 concentrations facilitating shrub recruitment. Apex predators initiate trophic cascades which can influence the abundance of many species across multiple trophic levels within ecosystems. Extirpation of apex predators is linked inextricably to pastoralism, but has not been considered as a factor contributing to shrub encroachment. Here, we ask if trophic cascades triggered by the extirpation of Australia's largest terrestrial predator, the dingo (Canis dingo), could be a driver of shrub encroachment in the Strzelecki Desert, Australia. We use aerial photographs spanning a 51-year period to compare shrub cover between areas where dingoes are historically rare and common. We then quantify contemporary patterns of shrub, shrub seedling and mammal abundances, and use structural equation modelling to compare competing trophic cascade hypotheses to explain how dingoes could influence shrub recruitment. Finally, we track the fate of seedlings of an encroaching shrub, hopbush (Dodonaea viscosa angustissima), during a period optimal for seedling recruitment, and quantify removal rates of hopbush seeds by rodents from enriched seed patches. Shrub cover was 26-48% greater in areas where dingoes were rare than common. Our structural equation modelling supported the hypothesis that dingo removal facilitates shrub encroachment by triggering a four level trophic cascade. According to this model, increased mesopredator abundance in the absence of dingoes results in suppressed abundance of consumers of shrub seeds and seedlings, rodents and rabbits respectively. In turn, suppressed abundances of rodents and rabbits in the absence of dingoes relaxed a recruitment bottleneck for shrubs. The results of our SEM were supported by results showing that rates of hopbush seedling survival and seed removal were 1·7 times greater and 2·1 times lower in areas where dingoes were rare than common. Our study provides evidence linking the suppression of an apex predator to the historic encroachment of shrubs. We contend that trophic cascades induced by apex predator extirpation may be an overlooked driver of shrub encroachment., (© 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.)

Ras-related nuclear protein (Ran) GTPase plays an important role in nucleo-cytoplasmic transportation of proteins and RNA, mitotic spindle assembly, microtubule assembly and nuclear envelope (NE) assembly. We previously identified the full-length cDNAs and a DNA of DlRan3A from longan (Dimocarpus longan Lour.) somatic embryos and demonstrated its possible roles in cell activities during longan somatic embryogenesis (SE). However, thus far little is known of how Ran functions in the signaling pathways in plant embryos in response to changing environmental stimuli. To discover more biological roles of DlRan3A, we observed DlRan3A located in the nucleus and detected abundant accumulation of DlRan3As in globular and cotyledon embryos during longan SE, which suggested its involvement in auxin signal pathways in longan early SE. The transcript level of the DlRan3A gene were also determined in longan embryogenic callus (EC) in response to different levels of exogenous phytohormones (indoleacetic acid (IAA), gibberellin A3 (GA3), salicylic acid (SA), methyl jasmonate (MeJA), and ethephon (Eth)), salt, sucrose, prolonged culturing period and light quality treatments. IAA (1mg/L), GA3 (12 mg/L), SA (75 μm), MeJA (50 and 100 μm), and Eth (50mg/L) modulate expression of DlRan3A to 1.3-1.4 folds, and the expression of DlRan3A was significantly affected by light quality, significantly induced to 2-fold by salt (10 g/L), 2.7-fold by sucrose (90 g/L) and was completely suppressed by prolonged cultivation (>40 days). Deletion analysis suggested that both activation and repression regulatory elements co-exist in the DlRan3A promoter sequence and that the key cis-acting elements included ones in response to auxin, SA, MeJA, and stress. Promoter activities were induced to the highest level by IAA followed by SA, GA3 and MeJA, while suppressed by ABA and Eth. Together, these results showed DlRan3A close involvement in phytohormones, light, and abiotic stress responsiveness during longan SE., (Copyright © 2015 Elsevier B.V. All rights reserved.)

In some Brazilian regions the Atlantic forest biome is currently restrict to fragments occurring amid monocultures, as sugarcane crops in the Northeast region. Important influence of forest remnants over mite fauna of permanent crops have been showed, however it has been poorly explored on annual crops. The first step for understanding ecological relationship in an agricultural systems is known its composition. The objective of this study was to investigate the plant-inhabiting mite fauna associated with sugarcane crop (Saccharum officinarum L.) (Poaceae) and caboatã (Cupania oblongifolia Mart.) (Sapindaceae) trees in the state of Alagoas, Brazil. Sugarcane stalks and sugarcane and caboatã apical, middle and basal leaves were sampled. A total of 2565 mites were collected from sugarcane and classified into seven families of Trombidiformes and Mesostigmata orders, with most individuals belonging to the Eriophyidae, Tetranychidae and Tarsonemidae families. Among predatory mites, the Phytoseiidae were the most common. A total of 1878 mites were found on C. oblongifolia and classified into 13 families of Trombidiformes and Mesostigmata orders. The most abundant phytophagous mite family on caboatã was also Eriophyidae. In contrast to sugarcane, Ascidae was the most common predatory mite family observed in caboatã. No phytophagous species were common to both sugarcane and C. oblongifolia. However two predatory mites were shared between host plants. Although mites associated with only one native species in the forest fragment were evaluated in this study, our preliminary results suggest Atlantic forest native vegetation can present an important role in the sugarcane agricultural system as a source of natural enemies.

The planting of trees on mine wastelands is an effective, long-term technique for phytoremediation of heavy metal-contaminated wastes. In this study, a pot experiment with seedlings of Koelreuteria paniculata under six treatments of local mine wastes was designed to determine the major constraints on tree establishment and to evaluate the feasibility of planting K. paniculata on manganese mine wastelands. Results showed that K. paniculata grew well in mine tailings, and also under a regime of equal amounts of mine tailings and soil provided in adjacent halves of pots. In contrast, mine sludge did not favor survival and growth because its clay texture limited fine root development. The bio-concentration factor and the translocation factor were mostly less than 1, indicating a low phytoextraction potential for K. paniculata. K. paniculata is suited to restore manganese mine sludge by mixing the mine sludge with local mine tailings or soil.

Sexual and asexual propagation of Xanthoceras sorbifolia natural populations in different habitats and their importance in population regeneration were studied. The results showed that X. sorbifolia populations were capable of the sexual and asexual propagation in 3 slope aspects, but a balance between the two propagation modes was observed. In sunny and semi-shady slope habitats, seedling amount and space-occupying competence were relatively high, suggesting that the sexual propagation was dominant. In semi-sunny slope habitat, the populations were superior in sexual sprout amount and space-occupying competence, suggesting that the predominant propagation mode was asexual. In the same habitats, asexual sprouts grew better than seedlings, while the growth of seedlings was in the order of sunny slope > semi-sunny slope > semi-shady slope on the basis of the same origin. The bottleneck stage appeared from seeds to seedlings for sexual propagation and from seedling to ramet for asexual propagation. X. sorbifolia invaded and settled in a way of sexual propagation in new habitats, and then rapidly occupied habitat space in a way of asexual propagation.

Orchard understory represents an important component of the orchards, performing numerous functions related to soil quality, water relations and microclimate, but little attention has been paid on its effect on soil C sequestration. In the face of global climate change, fruit producers also require techniques that increase carbon (C) sequestration in a cost-effective manner. Here we present a case study to compare the effects of understory management (sod culture vs. clean tillage) on soil C sequestration in four subtropical orchards. The results of a 10-year study indicated that the maintenance of sod significantly enhanced the soil C stock in the top 1 m of orchard soils. Relative to clean tillage, sod culture increased annual soil C sequestration by 2.85 t C ha(-1), suggesting that understory management based on sod culture offers promising potential for soil carbon sequestration. Considering that China has the largest area of orchards in the world and that few of these orchards currently have sod understories, the establishment and maintenance of sod in orchards can help China increase C sequestration and greatly contribute to achieving CO2 reduction targets at a regional scale and potentially at a national scale.

In this paper, different arid environments in the limestone area of Southwest China were simulated by using different concentrations (0%, 5%, 15%, 25%, and 30%) of PEG6000 (polyethylene glycol), and a gradient of exogenous Ca2+ (0, 15, 20, 25, and 30 mmol x L(-1) of CaCl2) was installed to simulate the high calcium soil environments, aimed to study the effects of different concentration PEG6000, CaCl2, and their interactions on the seed germination characteristics of Koelreuteria bipinnata, one of the preferred species in the ecological restoration in limestone area. Under the action of CaCl2 alone, medium or low concentration exogenous Ca2+ had lesser effect on the seed germination parameters, but high concentration exogenous Ca2+ had inhibition effect on the seed germination. Medium or low concentration CaC12 could increase the seedling fresh biomass. When the PEG6000 concentration increased from 0% to 25%, the seed germination rate, germination potential, germination index, and vigor index showed a significant decreasing trend, and the seedling fresh biomass decreased remarkably. When certain concentration of exogenous Ca2+ was exerted to the drought treatment groups, medium or low concentration CaCl2 improved the seed germination characteristics, which compensated the loss from drought stress to a certain degree. When the CaCl2 concentration was up to 30 mmol x L(-1), the seeds were hard to germinate. Additionally, no seeds germinated under the condition of PEG with the concentration of 30%. It was suggested that applying definite concentration of exogenous Ca2+ could increase the seedling fresh biomass under PEG6000 stress, and make the seedlings more adapt to arid environment.

Phytoremediation is a feasible alternative to remediate soils polluted with toxic elements, which can be enhanced by manipulating plant-microbe interactions. Regarding this, free-living saprophytic fungi that interact beneficially with roots have been scarcely studied. Thus, the aim of this study was to assess the effect of a saprophytic fungus, Lewia sp., on the plant growth and the ability of Dodonaea viscosa to phytoaccumulate or phytostabilize soluble and insoluble sources of lead in a solid support. The growth of D. viscosa was influenced by both Pb and Lewia sp. While seedlings exposed to Pb showed a decrease in biomass production, in seedlings grown without Pb the biomass was stimulated by Lewia sp. The fungus strongly stimulated the weight-to-length ratio in roots. Regardless of the treatment, D. viscosa accumulated 4.4-6.5 times more Pb in roots than in shoots, conducting to low translocation factors (< 0.2). The presence of Lewia sp. significantly improved Pb accumulation, achieving high bioconcentration factors (> 22), which was attributed to an increased bioavailability and uptake of Pb due to the fungus. This study demonstrated that Lewia sp. could improve Pb-phytostabilization by D. viscosa in soils polluted with soluble and insoluble forms of Pb.

In this study, an index system for the integrated risk evaluation of multiple disasters on the Longyan production in Fujian Province was constructed, based on the analysis of the major environmental factors affecting the Longyan growth and yield, and from the viewpoints of potential hazard of disaster-causing factors, vulnerability of hazard-affected body, and disaster prevention and mitigation capability of Longyan growth regions in the Province. In addition, an integrated evaluation model of multiple disasters was established to evaluate the risks of the major agro-meteorological disasters affecting the Longyan yield, based on the yearly meteorological data, Longyan planting area and yield, and other socio-economic data in Longyan growth region in Fujian, and by using the integral weight of risk indices determined by AHP and entropy weight coefficient methods. In the Province, the Longyan growth regions with light integrated risk of multiple disasters were distributed in the coastal counties (except Dongshan County) with low elevation south of Changle, the regions with severe and more severe integrated risk were mainly in Zhangping of Longyan, Dongshan, Pinghe, Nanjin, and Hua' an of Zhangzhou, Yongchun and Anxi of Quanzhou, north mountainous areas of Putian and Xianyou, Minqing, Minhou, Luoyuan, and mountainous areas of Fuzhou, and Fuan, Xiapu, and mountainous areas of Ninde, among which, the regions with severe integrated risk were in Dongshan, Zhangping, and other mountainous areas with high altitudes, and the regions with moderate integrated risk were distributed in the other areas of the Province.

Fatty acid composition, physicochemical and thermal properties and crystallization behavior of fats extracted from the seeds of krabok (Irvingia Malayana) and rambutan (Nephelium lappaceum L.) trees grown in Thailand were studied and compared with cocoa butter (CB). The krabok seed fat, KSF, consisted of 46.9% lauric and 40.3% myristic acids. It exhibited the highest saponification value and slip melting point but the lowest iodine values. The three fats displayed different crystallization behavior at 25°C. KSF crystallized into a mixture of β' and pseudo-β' structures with a one-step crystallization curve and high solid fat content (SFC). The fat showed simple DSC crystallization and melting thermograms with one distinct peak. The rambutan seed fat, RSF, consisted of 42.5% arachidic and 33.1% oleic acids. Its crystallization behavior was more similar to CB than KSF, displaying a two-step crystallization curve with SFC lower than that of KSF. RSF solidified into a mixture of β' and pseudo-β' before transforming to β after 24 h. The large spherulitic microstructures were observed in both KSF and RSF. According to these results, the Thai KSF and RSF exhibited physicochemical, thermal characteristics and crystallization behavior that could be suitable for specific applications in several areas of the food, cosmetic and pharmaceutical industries.

This paper reports the cryopreservation of Nephelium ramboutan-ake shoot tips derived from in vitro shoot multiplication and in vitro seed germination using vitrification. Preculture with either 0.5 M sucrose for 2 days or a combination of 0.3 M sucrose and 0.5 M glycerol for 3 days enhanced dehydration tolerance and resulted in the highest survival of shoot tips; however, none of the shoot tips withstood liquid nitrogen (LN) exposure. The use of a lower temperature (0 degree C) during exposure to plant vitrification solution (PVS2) led to higher survival of shoot tips, compared to exposure at 25 degree C. The survival percentage of shoot tips exposed to PVS2 for up to 20 min at 0°C was 83.3 percent. It was only 53.3 percent when shoot tips were exposed to PVS2 at 25 degree C for 5 min. The importance of vitamin C for reducing oxidative stress in shoots tips was demonstrated. The addition of 0.28 mM vitamin C during critical steps of the vitrification process resulted in a high survival (96.7 percent) without LN exposure, compared to 73.3 percent for shoot tips not treated with vitamin C. Moreover, 3.3 percent shoot tips withstood LN exposure when vitamin C was added during the loading step. This result suggests that cryopreservation is possible for this tropical, recalcitrant seeded tree species.

The potential role of arbuscular mycorrhizal fungi (AMF) in the revegetation of an alkaline gold mine tailing was studied in Barberton, South Africa. The tailing, characterized by a slow spontaneous plant succession, is colonized by the shrub Dodonaea viscosa and the grasses, Andropogon eucomus and Imperata cylindrica, all colonized by AMF. The effectiveness of mycorrhizal colonization in grasses was tested under laboratory conditions using fungal isolates of various origins. Both grasses were highly mycorrhiza dependent, and the presence of mycorrhizal colonization significantly increased their biomass and survival rates. The fungi originating from the gold tailing were better adapted to the special conditions of the tailing than the control isolate. Although the total colonization rate found for native fungi was lower than for fungi from non-polluted sites, they were more vital and more effective in promoting plant growth. The results obtained might serve as a practical approach to the phytostabilization of alkaline gold tailings.

Two-dimensional gel electrophoresis (2-DE), coupled with mass spectroscopy, was used to study seed abortion in Dimocarpus longan Lour. (cv. Minjiao 64-1) by comparing normal and aborted seeds at three developmental stages. More than 1,000 protein spots were reproducibly detected in 2-DE gels, with 43 protein spots being significantly altered in their intensity between normal and aborted seeds at least at one stage. Thirty-five proteins were identified by matrix-assisted laser desorption ionization-time of flight-tandem mass spectrometry (MALDI-TOF-MS/MS) analysis and protein database searching. Most of the identified proteins were associated with a variety of functions, including energy and metabolism (30%), programed cell death (9%), antioxidative processes (14%), chaperonin (23%), cell division, amino acid metabolism, secondary metabolism, and other functional classes. Furthermore, the expression patterns of HSP70 and cytosolic ascorbate peroxidase (cAPX) were validated by immunoblotting analysis. This study provides a novel, global insight into proteomic differences between normal and aborted seeds in longan. We anticipate that identification of the differentially expressed proteins may lead to a better understanding of the molecular basis for seed abortion in longan.

Based on the continuous observation on located trees and branches, the phenology and sexual reproductive process of Xanthoceras sorbifolia Bunge in an annual growth cycle in Wudan area were investigated, and the relationships between fruit growth process of X. sorbifolia and effective accumulative temperature as well as the quantitative dynamics of flowers and fruits were studied. The results showed that the phenology of X. sorbifolia had a significant linear correlation with effective accumulative temperature, and there was a time sequence in the male flower silk elongating and antheral unfolding. The fruits of X. sorbifolia experienced three times of dropping during their growth process. The pollination rate was 26.4%, flower dropping rate was 73.6%, and fruit dropping rate was 92.9%, suggesting that the dropping of flowers and fruits was very serious. The fruits had a quicker vertical growth from early June to mid June and a quicker horizontal growth in the last ten-day of June, with the highest ratio of vertical to horizontal length being 2.17. The individuals of X. sorbifolia had definite differences in their phenology, which was disadvantageous to the cross pollination among the individuals, and the enhancement of pollination rate.

Saplings of many canopy tree species in winter deciduous forests receive the major portion of their light budget for their growing season prior to canopy closure in the spring. This period of high light may be critical for achieving a positive carbon (C) gain, thus contributing strongly to their growth and survival. This study of saplings of Aesculus glabra and Acer saccharum in Trelease Woods, Illinois, USA, tested this hypothesis experimentally by placing tents of shade cloth over saplings during their spring period of high light prior to canopy closure in three consecutive years. Leaf senescence began 16 days (year 0) and 60 days (year 1) earlier for shaded A. glabra saplings than control saplings. No change in senescence occurred for A. saccharum. The annual absolute growth in stem diameter of both species was negligible or negative for shaded saplings, but positive for control saplings. Only 7% of the shaded A. glabra saplings were alive after 2 years, while all control saplings survived for 3 years; only 20% of the shaded A. saccharum saplings survived for 3 years, while 73% of control saplings were alive after the same period. Early spring leaf out is a critical mechanism that allows the long-term persistence of saplings of these species in this winter deciduous forest. Studies and models of C gain, growth, and survival of saplings in deciduous forests may need to take into account their spring phenology because saplings of many species are actually "sun" individuals in the spring prior to their longer period in the summer shade.

In this paper, the seedling's early growth and establishment of Pometia tomentosa, a canopy tree species in Xishuangbanna tropical seasonal rainforest, were investigated under different illumination gradients (gap center, gap edge, and under canopy). The seedling height, basal stem diameter, total dry mass, leaf area per seedling, and relative growth rate at early stage peaked in gap center, with the values of 24.45 cm, 3.17 mm, 0.79 g, 122.45 cm2, and 14.78 x 10(-3) g x d(-1), respectively. The seedlings had a higher root-shoot ratio under canopy (0.87) than in gap center (0.20) due to the influence of both illumination and water. The brighter illumination in gap center facilitated the growth of established seedlings, with the peaks of seedling height (31.48 cm), basal stem diameter (3.80 mm), total dry mass (2.22 g), leaf area per seedling (174.52 cm2), relative growth rate (2.29 x 10(-3) g x d(-1)), and net assimilation rate (2.54 x 10(-5) g x cm(-2) d(-1)) attained by the end of the investigation. The death of established seedlings might be closely related to water stress. Under canopy, the death rate caused by water stress was the highest (26.88%) but that caused by the predation of vertebrates was the lowest (2.93%), which in final, induced the highest survival rate (70.19%) of the seedlings. Illumination was the important factor affecting the morphological regulation of P. tomentosa seedlings. In gap center, the specific leaf area of the seedlings at their different growth stages was the smallest, but their relative growth rate and net assimilation rate were the greatest. The root-shoot ratio of established seedlings peaked at gap edge (0.33), suggesting that water stress and illumination were the important factors affecting the biomass allocation of established seedlings.

We investigated whether arbuscular mycorrhizas influenced growth and survival of seedlings in an extremely impoverished and highly disturbed soil. Seedlings of four plants species native to the site were either inoculated with native sporocarpic arbuscular mycorrhizal (AM) fungi or fertilised prior to transplanting, and followed over 86 weeks at the site. One treatment was also irrigated with N-rich leachate from the site. In a laboratory experiment, seedlings were fertilised with excess P for 6 weeks, and location of the P store determined. Growth and survival of AM and fertilised seedlings were similar at the site. Inoculated mycorrhizal fungi and roots appeared to extend into the surrounding soil together. P concentration in leaves of all plants was extremely low. Irrigation with leachate increased growth of seedlings. In the laboratory experiment, significantly more P was stored in roots than shoots. We suggest that successful revegetation of extremely disturbed and impoverished sites requires selection of mycorrhizal fungi and plants to suit the edaphic conditions and methods of out-planting.

The recent identification of DAD (defender against apoptotic death) gene in plants suggests that the N-linked glycosylation of proteins could be an important control point of plant programmed cell death. In this paper we describe the effects of Tunicamycin, an inhibitor of N-linked protein glycosylation, and Brefeldin A, an inhibitor of protein trafficking from the Golgi apparatus, on sycamore (Acer pseudoplatanus L.) cell cultures. These two chemicals proved able to induce a strong acceleration of the cell death; changes in cell and nucleus morphology; an increase in DNA fragmentation, detectable by a specific immunological reaction; and the presence of oligonucleosomal-size fragments (laddering) in DNA gel electrophoresis. Moreover, Brefeldin A, but not Tunicamycin, strongly stimulated the production of hydrogen peroxide. These results indicate that also in plants chemicals interfering with the activities of endoplasmic reticulum and of Golgi apparatus strongly induce a form of programmed cell death showing apoptotic features.