Industrial Chicory Research Articles

Effects of chicory (Cichorium intybus L.) distillation wastewater on antioxidant status, immune response, cecal microbial population, growth performance and meat quality in broiler chickens

Chicory (Cichorium intybus L.) distillation wastewater (CDWW) is a dark viscous liquid obtained as a by-product of the processing of industrial chicory (Cichorium intybus). The current study aimed to investigate the influence of dietary CDWW on growth performance, oxidative status, immune response, meat quality, and cecal microbial population of broiler chicken. In total, 400 one-d-old male chickens (Ross 308) were allotted into four groups in ten replicates of 10 chickens each. The 1st group was fed a basal diet without CDWW (control), whereas the 2nd, 3rd, and 4th groups were fed diets containing CDWW (15, 30, and 45 mL/kg diet, respectively) for 42 days. At day 42 of age, CDWW significantly increased body weight gain (P < 0.01), improved feed efficiency, and reduced mortality rate (P < 0.05). Treatments did not have a significant effect on feed intake. The 30 and 45 mL of CDWW groups showed an increase in hematological values than other groups (P < 0.05). The ALT, AST, ALP, triglyceride, and cholesterol concentration in serum were lower and immunoglobulins (IgA, IgG, IgM) were greater in 30 and 45 mL /kg of CDWW groups than other groups (P < 0.05). The malondialdehyde (MDA) content in serum, liver, breast, and lipid peroxide (LPO) in breast decreased by 30 and 45 mL of CDWW supplementation (P < 0.05). The oxidative enzymes activities in serum, liver, and breast were greater in 30 and 45 mL /kg of CDWW than other groups (P < 0.05). Also, quality properties and composition of beast were improved and ceceal harmful microbial counts were decreased by the 30 and 45 mL /kg of CDWW (P < 0.05). In conclusion, the CDWW at 30 and 45 mL /kg improved the broiler's performance, meat quality, as well as blood indices and cecal microbial load by enhancing antioxidant activities and suppressing lipid peroxidation in meat.

Use of Pseudomonas protegens to Control Root Rot Disease Caused by Boeremia exigua var. exigua in Industrial Chicory (Cichorium intybus var. sativum Bisch.).

Boeremia exigua var. exigua is a recurrent pathogen causing root rot in industrial chicory. Currently, there is no chemical or varietal control for this disease, and thus, management strategies need to be developed. This study determined the biocontrol effect of strains of Pseudomonas protegens bacteria with antimicrobial compounds on the fungus B. exigua var. exigua under in vitro, in vivo, and field conditions. In addition, root colonization by these bacteria was estimated by the phlD-specific PCR-based dilution end point assay. Eighteen isolates of Pseudomonas spp were evaluated, and the strains that showed the greatest in vitro inhibition of fungal mycelial growth (mm), Ca10A and ChB7, were selected. Inoculation with the strain ChB7 showed less severity (necrotic area) under in vivo conditions (root trials) compared with the control inoculated with the pathogen (p ≤ 0.05). The molecular analysis revealed that the root colonization of plants grown in pots was equal to or greater than 70%. Similar levels were observed in the field trials conducted at the Selva Negra and Canteras experimental stations (2015-2016 season), with values ranging from 85.7 to 70.5% and from 75.0 to 79.5%, respectively. Regarding yield (ton ha-1), values were higher in the treatments inoculated with strains Ca10A and ChB7 (p ≤ 0.05) at both experimental sites, while a lower incidence and severity of root rot were observed at Selva Negra. These results suggest that the Chilean strains of P. protegens are a promising tool for the control of root diseases in industrial chicory.

CRISPR/Cas9-Targeted Mutagenesis of CiGAS and CiGAO to Reduce Bitterness in Chicory (Cichorium intybus L.).

Chicory (Cichorium intybus L.), a member of the Asteraceae family, is known for its numerous health benefits, including its prebiotic, digestive, antioxidant or anti-inflammatory effects. Used as a coffee substitute, chicory roots is also appreciated for its bitterness, which can prove to be a disadvantage for other uses in food. The bitterness of chicory is largely linked to the presence of sesquiterpene lactones (STLs) in the roots. In order to create less bitter industrial chicory varieties, CRISPR/Cas9 technology was used to inhibit the first two genes of the STL biosynthetic pathway: germacrene A synthase (CiGAS), short form, and germacrene A oxidase (CiGAO). To determine the impact of these reductions on the perception of bitterness, a sensory analysis of 13 field-grown chicories genotypes, contrasting for their STL composition, allowed the construction of obtain a bitterness scale by correlating STL content with perceived bitterness. The edited chicories were positioned on this scale according to their STL content. Biallelic mutations in two of the copies of CiGAS-short form or in the CiGAO gene led to a reduction in STL content of edited chicories and a reduction in bitterness, or even an absence of perception, was obtained for some mutants. The use of the CRISPR/Cas9 tool as well as the choice of targets therefore makes it possible to modulate the bitterness of chicory.

Identification and characterization of CYP71 subclade cytochrome P450 enzymes involved in the biosynthesis of bitterness compounds in Cichorium intybus.

Industrial chicory (Cichorium intybus var. sativum) and witloof (C. intybus var. foliosum) are crops with an important economic value, mainly cultivated for inulin production and as a leafy vegetable, respectively. Both crops are rich in nutritionally relevant specialized metabolites with beneficial effects for human health. However, their bitter taste, caused by the sesquiterpene lactones (SLs) produced in leaves and taproot, limits wider applications in the food industry. Changing the bitterness would thus create new opportunities with a great economic impact. Known genes encoding enzymes involved in the SL biosynthetic pathway are GERMACRENE A SYNTHASE (GAS), GERMACRENE A OXIDASE (GAO), COSTUNOLIDE SYNTHASE (COS) and KAUNIOLIDE SYNTHASE (KLS). In this study, we integrated genome and transcriptome mining to further unravel SL biosynthesis. We found that C. intybus SL biosynthesis is controlled by the phytohormone methyl jasmonate (MeJA). Gene family annotation and MeJA inducibility enabled the pinpointing of candidate genes related with the SL biosynthetic pathway. We specifically focused on members of subclade CYP71 of the cytochrome P450 family. We verified the biochemical activity of 14C. intybus CYP71 enzymes transiently produced in Nicotiana benthamiana and identified several functional paralogs for each of the GAO, COS and KLS genes, pointing to redundancy in and robustness of the SL biosynthetic pathway. Gene functionality was further analyzed using CRISPR/Cas9 genome editing in C. intybus. Metabolite profiling of mutant C. intybus lines demonstrated a successful reduction in SL metabolite production. Together, this study increases our insights into the C. intybus SL biosynthetic pathway and paves the way for the engineering of C. intybus bitterness.

Industrial chicory genome gives insights into the molecular timetable of anther development and male sterility.

Industrial chicory (Cichorium intybus var. sativum) is a biannual crop mostly cultivated for extraction of inulin, a fructose polymer used as a dietary fiber. F1 hybrid breeding is a promising breeding strategy in chicory but relies on stable male sterile lines to prevent self-pollination. Here, we report the assembly and annotation of a new industrial chicory reference genome. Additionally, we performed RNA-Seq on subsequent stages of flower bud development of a fertile line and two cytoplasmic male sterile (CMS) clones. Comparison of fertile and CMS flower bud transcriptomes combined with morphological microscopic analysis of anthers, provided a molecular understanding of anther development and identified key genes in a range of underlying processes, including tapetum development, sink establishment, pollen wall development and anther dehiscence. We also described the role of phytohormones in the regulation of these processes under normal fertile flower bud development. In parallel, we evaluated which processes are disturbed in CMS clones and could contribute to the male sterile phenotype. Taken together, this study provides a state-of-the-art industrial chicory reference genome, an annotated and curated candidate gene set related to anther development and male sterility as well as a detailed molecular timetable of flower bud development in fertile and CMS lines.

Cichorium intybus L. Hairy Roots as a Platform for Antimicrobial Activity.

Industrial chicory is an important crop for its high dietary fibre content. Besides inulin, chicory taproots contain interesting secondary metabolite compounds, which possess bioactive properties. Hairy roots are differentiated plant cell cultures that have shown to be feasible biotechnological hosts for the production of several plant-derived molecules. In this study, hairy roots of industrial chicory cultivars were established, and their potential as a source of antimicrobial ingredients was assessed. It was shown that hot water extracts of hairy roots possessed antimicrobial activity against relevant human microbes, whereas corresponding chicory taproots did not show activity. Remarkably, a significant antimicrobial activity of hot water extracts of chicory hairy roots towards methicillin-resistant Staphylococcus aureus was observed, indicating a high potential of hairy roots as a host for production of antimicrobial agents.

Chicory: Understanding the Effects and Effectors of This Functional Food.

Industrial chicory has been the subject of numerous studies, most of which provide clinical observations on its health effects. Whether it is the roasted root, the flour obtained from the roots or the different classes of molecules that enter into the composition of this plant, understanding the molecular mechanisms of action on the human organism remains incomplete. In this study, we were interested in three molecules or classes of molecules present in chicory root: fructose, chlorogenic acids, and sesquiterpene lactones. We conducted experiments on the murine model and performed a nutrigenomic analysis, a metabolic hormone assay and a gut microbiota analysis, associated with in vitro observations for different responses. We have highlighted a large number of effects of all these classes of molecules that suggest a pro-apoptotic activity, an anti-inflammatory, antimicrobial, antioxidant, hypolipidemic and hypoglycemic effect and also an important role in appetite regulation. A significant prebiotic activity was also identified. Fructose seems to be the most involved in these activities, contributing to approximately 83% of recorded responses, but the other classes of tested molecules have shown a specific role for these different effects, with an estimated contribution of 23–24%.

PP 1/52 (4) Weeds in sugar and fodder beet and industrial chicory

PP 1/52 (4) Weeds in sugar and fodder beet and industrial chicory

Chromosome doubling of Cichorium intybus L. haploids through protoplast regeneration

Industrial chicory (Cichorium intybus L.) is mainly grown for inulin production. To enhance production and uniformity, hybrid cultivars are preferred. Therefore, a controlled pollination system and homozygous parental lines are needed. The most desirable pollination control system is cytoplasmic male sterility (CMS). A new, naturally induced CMS has been reported by Van der Veken et al. (2018). To regenerate homozygous parental lines of modern industrial chicory cultivars, different haploid inducing techniques have been compared and evaluated. The only successful method was intergeneric hybridization with Cicerbita alpina (Dore et al., 1996), yielding haploid plants. Here we show that protoplast regeneration is an efficient tool for chromosome doubling of these haploids. The presented method can be used for chromosome doubling of slowly developing haploids.

Technology and Process Design for Phenols Recovery from Industrial Chicory (Chicorium intybus) Leftovers.

Vegetal leftovers from the agro–food industry represent a huge source of primary and secondary metabolites, vitamin, mineral salts and soluble as well as insoluble fibers. Economic reports on the growth in the polyphenol market have driven us to focus our investigation on chicory (Chicorium intybus L.), which is one of the most popular horticultural plants in the world and a rich source of phenolic compounds. Ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE) and their simultaneous combination, using either ethanol/water or water alone (also sub-critical), have been investigated with the aim of designing a green and efficient extraction process. Higher total-polyphenol yields as well as dramatic reductions in extraction times and solvent consumption have been obtained under these conditions. ANOVA test for analyses of variance followed by the Tukey honestly significant difference (HSD) post-hoc test of multiple comparisons was used in the statistical analysis. MAE experiments performed with sub-critical water, and MW/US experiments with an ethanol solution have shown polyphenol recovery values of up to ~3 g of gallic acid equivalents (GAE) per kg of fresh material in only 15 min, while conventional extraction required 240 min to obtain the same result.

Cichorium intybus L. × Cicerbita alpina Walbr.: doubled haploid chicory induction and CENH3 characterization

Intergeneric hybridization between industrial chicory (Cichorium intybus L.) and Cicerbita alpina Walbr. induces interspecific hybrids and haploid chicory plants after in vitro embryo rescue. The protocol yielded haploids in 5 out of 12 cultivars pollinated; altogether 18 haploids were regenerated from 2836 embryos, with a maximum efficiency of 1.96% haploids per cross. Obtained haploids were chromosome doubled with mitosis inhibitors trifluralin and oryzalin; exposure to 0.05 g L−1 oryzalin during one week was the most efficient treatment to regenerate doubled haploids. Inbreeding effects in vitro were limited, but the ploidy level affects morphology. Transcriptome sequencing revealed two unique copies of CENH3 in Cicerbita alpina Walbr. Comparison of CENH3.1 protein sequences of Cicerbita and Cichorium obtained through transcriptome and whole shotgun genome sequencing revealed two amino-acid substitutions at critical residues of the histone fold domain. These particular changes cause chromosome elimination and reduced centromere loading in several other species and might indicate a CENH3-dependent mechanism causing chromosome elimination of parental chromosomes during Cichorium × Cicerbita intergeneric hybridization. Our results provide insights in chromosome elimination and might increase the efficiency of haploid induction in Cichorium.

Temperature related instability of a naturally induced cytoplasmic male sterility in industrial chicory (Cichorium intybus L.)

AbstractNatural alloplasmic cytoplasmic male sterile (CMS) clones of industrial chicory were obtained after crossing wild chicory with selected breeding lines. We investigated the CMS stability of 10 clones in various environmental growing conditions. CMS was stable under cool growing conditions in most of them. Fertility restoration, based on pollen production scores, was observed in all clones after a period of hot temperatures. The early flower bud stage was sensitive, resulting in fertile flowers 12–17 days after exposure to high temperatures. Experiments under controlled growing conditions at 15°C demonstrated that a heat shock of 2 days at 25 or 30°C was sufficient to restore fertility. Sterile flowers were formed when plants were again grown at lower temperatures. Significant differences between individual clones were observed, indicating the potential of genetic selection to obtain stable CMS parent lines.

Selection and validation of reference genes for quantitative real-time PCR analysis of gene expression in Cichorium intybus.

Plant polyphenols represent a huge reservoir of bioactive compounds. Industrial chicory, an important crop from northwestern Europe, accumulates an original combination of such compounds, i.e., chlorogenic, isochlorogenic, caftaric, and chicoric acids arising from the phenylpropanoid pathway. For a complete understanding of these biochemical pathways, analyses of gene expression using quantitative real-time PCR (qRT-PCR) should be considered. Because cell cultures are a model of choice for specialized metabolism investigations, this study described for the first time the validation of reference genes for this system in chicory. Eighteen potential reference genes were obtained by mining expressed sequence tag databases of chicory for orthologs of Arabidopsis thaliana genes currently used as reference genes. Twelve genes passed the qRT-PCR standard requirements and their expression stability across different samples was tested using three distinct softwares: geNorm, NormFinder, and BestKeeper. In cell cultures grown under various conditions, TIP41 (TIP41 like protein) was shown to be the most stable gene. Further validation of the proposed reference genes was done by normalization of expression levels of a group of genes of interest. In order to assess the potentiality of the proposed list of candidate reference genes, theses genes were in parallel tested on another experimental design, i.e., chicory seedlings. In this case, the best reference gene identified was Clath (Clathrin adaptator complex subunit). The results highlight the importance of the use of properly validated reference genes to achieve relevant interpretation of qRT-PCR analyses. Here, we provide a list of reference genes suitable for future gene expression studies in chicory.

Exploration of genetic diversity within Cichorium endivia and Cichorium intybus with focus on the gene pool of industrial chicory

The present study used 15 simple sequence repeat loci to characterize the genetic diversity of the germplasm that originated the current industrial chicory and to establish the relationships between and inside Cichorium intybus L. and Cichorium endivia L. Initially we analyzed 19 cultivated C.endivia accessions, 27 wild and 155 cultivated C. intybus accessions distributed among three groups: 83 root chicories, 42 Witloof and 30 leaf chicories. The leaf chicories comprised cultivars corresponding to the Radicchio, Sugarloaf and Catalogne subgroups. The latter has not been previously included in any genetic diversity study. Subsequently, 1297 individuals from the 15 modern root chicory cultivars at the origin of the breeding of the current industrial root chicory cultivars were analyzed. Although the accessions of C.endivia and C. intybus were clearly separated from each other, seven wild C. intybus individuals were genetically closer to C. endivia than to C. intybus , revealing complex genetic interrelationships between these species. The differentiation of C. intybus into three cultivar groups (Witloof, root chicory and leaf chicory) was confirmed. The leaf chicory individuals were divided into three genetic subgroups, corresponding to the Radicchio, Sugarloaf and Catalogne cultivars, thus attesting to the validity of the classification based on morphological factors. Clear differentiation was ob- served among the Belgian, Polish and Austrian modern industrial root cultivars, but not among the French industrial modern root cultivars. The high phenotypic and genetic variability of the modern industrial root cultivars indicates that this germplasm constitutes a useful gene pool for cultivar improvement and selection.

A method for the simultaneous determination of chlorogenic acid and sesquiterpene lactone content in industrial chicory root foodstuffs.

A method for the simultaneous determination of free chlorogenic acids (CGA) and sesquiterpene lactones (STL) in chicory root and its dried (flour) and roasted (grain) forms is described. The method uses one extraction and one analysis for all chicory root products. Various solvents with low to high polarity, such as methanol, chloroform, or n-hexane, were tested alone, in combination in different proportions or with acidified or neutral aqueous solvent. The water/chloroform/methanol (30/30/40, v/v/v) mixture generated the best extraction yield, 21% higher than alcohol mixtures. The profiling of CGA and STL content was performed through a conventional HPLC-DAD method using a PFP core shell column in a fast single run. Good retention time and area repeatability (RDD mean % 0.46 and 5.6, resp.) and linearity (R 2 ≥ 0.96) were obtained. The STL and chlorogenic acids levels determined were 254.7 and 100.2 μg/g of dry matter in the root, 792.5 and 1,547 μg/g in flour, and 160.4 and 822.5 μg/g in the roasted grains, respectively. With an average recovery of 106% and precision of 90%, this method is rapid, reproducible, and straightforward way to quantify the chlorogenic acids and STL in chicory raw material and end products.

Mutations in chicory FEH genes are statistically associated with enhanced resistance to post-harvest inulin depolymerization.

Nucleotidic polymorphisms were identified in fructan exohydrolases genes which are statistically associated with enhanced susceptibility to post-harvest inulin depolymerization. Industrial chicory (Cichorium intybus L.) root is the main commercial source of inulin, a linear fructose polymer used as dietary fiber. Post-harvest, inulin is depolymerized into fructose which drastically increases processing cost. To identify genetic variations associated with enhanced susceptibility to post-harvest inulin depolymerization and related free sugars content increase, we used a candidate-gene approach focused on inulin and sucrose synthesis and degradation genes, all members of the family 32 of glycoside hydrolases (GH32). Polymorphism in these genes was first investigated by carrying out EcoTILLING on two groups of chicory breeding lines exhibiting contrasted response to post-harvest inulin depolymerization. This allowed the identification of polymorphisms significantly associated with depolymerization in three fructan exohydrolase genes (FEH). This association was confirmed on a wider panel of 116 unrelated families in which the FEH polymorphism explained 35% of the post-harvest variance for inulin content, 36% of variance for sucrose content, 18% for inulin degree of polymerization, 23% for free fructose content and 22% for free glucose content. These polymorphisms were associated with significant post-harvest changes of inulin content, inulin chain length and free sugars content.

High Resolution Melting Analysis as a Rapid and Highly Sensitive Method for Cichorium Plasmotype Characterization

Somatic hybridization in Cichorium species has already been extensively investigated. Hybrid or cybrid characterization requires an effective plasmotype screening method. We evaluated high resolution melting (HRM) analysis for the detection of specific mitochondrial (mt) and chloroplast (cp) markers to distinguish two industrial chicory (Cichorium intybus var. sativum) plasmotypes from five wild type chicory (C. intybus) and two endive (C. endivia) plasmotypes. Three mt (coxII-2, cob-1, and cob-2) and three cp HRM markers (trnL-trnF, trnL-trnF-2, and ndhF-1) were successfully developed. Two markers (coxII-2 and trnL-trnF) were additionally able to discriminate heterozygous plasmotypes containing at least 25 % of one parental plasmotype. Moreover, the technique was successfully used to characterize the cytoplasms of 50 simple sequence repeats (SSR) confirmed somatic hybrids of C. intybus var. sativum ‘VL52’ and C. endivia var. crispum ‘Wallone Despa’. HRM enables a rapid (less than 2 h) and efficient high-throughput scanning of multiple fragments due to the 384-well plates and is cost efficient because of its small reaction volume of 10 μl. This is the first report on the use of HRM analysis on Cichorium species. The technique is a fast and simple alternative for laborious and costly sequencing in plasmotyping regenerants obtained after somatic fusion.

OPTIMISATION OF SOMATIC HYBRIDISATION IN CICHORIUM SPECIES

Improving the inulin production in the root of industrial chicory by conventional breeding has reached its limit. Therefore, we aimed to increase genetic variability in industrial chicory (Cichorium intybus) to enhance its inulin production. To this end, we executed symmetric protoplast fusions between industrial chicory on the one hand and endive or a wild type Cichorium intybus foliosum on the other hand. In order to produce plantlets, efficient protocols needed to be established for protoplast fusion and regeneration, and for the screening of the putative hybrids. We created a regeneration protocol by which we can produce plantlets out of protoplasts using low melting point agarose beads surrounded by liquid medium. Two weeks after protoplast isolation, 60% of the initial incubated protoplasts showed microcolony development in the beads. After transfer to solid medium, containing 0.5 mg L-1 IAA and 0.5 mg L-1 BAP, shoots were induced on the developing calli. Three months after protoplast isolation, the first plants were recovered. Protoplasts from different genotypes of C. intybus sativum and C. intybus foliosum could be regenerated. Symmetric protoplast fusion was performed using PEG-induced, chemical fusion. Industrial chicory (C. intybus sativum), endive (C. endivia crispum) and wild chicory (C. intybus foliosum) were used as fusion partners. Up to 30% of the regenerants after fusion between industrial chicory and endive were hybrids. The fusion of industrial chicory with wild chicory produced on average 4% hybrid regenerants. Microsatellite markers confirmed the hybridity of the putative fusion products. These findings enable us to produce, fuse and regenerate protoplasts of different Cichorium species in a rapid and efficient way. Moreover, the methods for symmetric protoplast fusion and regeneration presented in this study, can directly contribute to further research on asymmetric protoplast fusion experiments between these three species. This way, CMS could possibly be introduced by combining the nucleus of industrial chicory with the cytoplasm of other Cichorium types.

Comparison of image analysis and direct measurement of UPOV taxonomic characteristics for variety discrimination as determined over five growing seasons, using industrial chicory as a model crop

Tests for distinctness, uniformity and stability (DUS) are an essential component of variety registration and granting plant breeders’ rights. This study, performed on industrial chicory (Cichorium intybus L.), included (1) an evaluation of the discriminating power of the UPOV characteristics and (2) a comparison of the root shape between the UPOV-based characteristics and characteristics determined via image analysis. Five consecutive growing periods were studied to assess the long-term stability of the parameters. Lack of discriminating power of characteristics for examining distinctness may impede breeding progress by failing to discriminate novel candidate varieties. However, a balance needs to be set so that newly introduced characteristics or new evaluation methodologies are not too powerful as to damage the protection of registered varieties. The results showed great differences in the discriminating power of the UPOV characteristics. The elimination of some of these low-discriminating characteristics would probably result in savings, but would have no consequences on the decisions taken by DUS testing authorities. Image analysis-derived characteristics could either replace currently-used parameters or provide additional characteristics with good discriminating power, determined in an objective and standardized way. Here we discuss possible implications for variety registration.

Evaluation of cold stress of young industrial chicory (Cichorium intybus L.) by chlorophyll a fluorescence imaging. II. Dark relaxation kinetics

Industrial chicory, Cichorium intybus L., has rather poor early vigour under the typical early spring morning conditions of low temperatures and high light intensity. Screening tools are being developed to assess the cold tolerance/sensitivity of young industrial chicory plants under these conditions. Refinement of such tools requires better understanding of the plants' physiological responses. In this paper we discuss the effects of growth temperature (GT), measurement temperature (MT), and measuring light intensity (ML) on the relaxation of the Kautsky curve. We chose the chicory variety 'Hera', as it is known to possess a good average early vigour. Young plants of the variety 'Hera' were grown at three temperatures (GT): 16°C (reference), 8°C (intermediate), and 4°C (cold stress). The dark relaxation kinetics were analyzed at different light intensities (ML) in combination with different measurement temperatures (MT). The three components of the nonphotochemical quenching process (NPQE, NPQT, and NPQI) were determined. NPQE was not affected by GT but was significantly affected by MT and ML. NPQT and NPQI were affected by all factors and their interactions. An acclimation effect for plants grown at low GT was detected. Acclimation resulted in lower NPQT and NPQI values. The halftime of the inhibition depending on NPQ (NPQI) was not affected by any of the factors investigated. Based on the data generated, we conclude that NPQI is a valuable parameter for screening the cold sensitivity of young industrial chicory plants.