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The global increase in temperature and associated meteorological disruptions, such as the earlier onset of high temperatures and disruptions in precipitation, are becoming severely limiting factors in crop cultivation. Chickpea, as a cool season crop, is under the direct influence of heat and drought stress that is not only affecting this crop in its podding stage but, with current climate trends, the drought and heat are now also affecting earlier stages, such as flowering. The deteriorating effects of heat and droughts include reduced flowering, abortion of flowers and absence of podding; thus, this is severely affecting crop yield. Further research has been conducted to identify the genes correlated to higher stress tolerance and to utilize them in developing more tolerant varieties. Different alleviation approaches have been also tested and it has been determined that some positive effects can be seen in supplementation with Zn through melioration of water relations, seed priming and some transgenic and genome editing approaches. Breeding strategies for future chickpea varieties have been focused on the identification of varieties with more tolerant traits for an improved yield under stressed conditions. In this review, we have reviewed recent strategies and biotechnological approaches that have been used with chickpea crops to address the two major abiotic stresses (heat and drought) linked to future climate change. [ABSTRACT FROM AUTHOR]

People have an ancient and strong bond to flowers, which are known to have a positive effect on the mood. During the COVID-19 pandemic, sales of ornamental plants increased, and many turned to gardening, possibly as a way to cope with ubiquitous increases in negative mood following lockdowns and social isolation. The nature of the special bond between humans and flowers requires additional elucidation. To this means, we conducted a comprehensive online mixed methods study, surveying 253 individuals (ages 18–83) from diverse ethnic backgrounds and continents, regarding their thoughts and feelings towards photos of flowers, nature scenes and flower drawings. We found that looking at pictures and drawings of flowers, as well as nature scenes induced positive emotions, and participants reported a variety of positive responses to the images. More specifically, we found associations of flowers with femininity, and connotations to particular flowers that were affected by geographical location. While nature scene photos induced positive reactions, flower photos were preferred, denying a mere substitution of nature by flowers and vice versa. Drawings of flowers elicited less positive emotions than photos, as people related more to the art than to the flower itself. Our study reveals the importance of ornamental flowers and nature in our life and well-being, and as such their cultivation and promotion are essential. [ABSTRACT FROM AUTHOR]

At the reproductive stage, lily plants bear two morphological types of mature leaves, one at the lower and one at the upper part of the stem. At the vegetative stage, all the leaves are similar to each other and to the reproductive plant's lower leaves. This heterophylly has not yet been explored. In this study, we show that it is not a result of the plant's age but rather an outcome of floral induction. The induction appears as an on‐going process, during which the meristem still produces leaves but progressively becomes committed to reproduction. This intermediate period lasts until the ultimate switch to flower primordia occurs. The leaves produced during floral induction, termed here as "inductive," appear at the upper part of the stem. Besides their typical higher stomata density, these leaves have a poly‐layered palisade mesophyll, whose cells exhibit a unique morphology and contain more chlorophyll than leaves of vegetative plants. These leaves display higher carbon assimilation, soluble sugar production, and chloroplast‐lipid accumulation. Accordingly, genes associated with stomata, chloroplast, and photosynthesis are upregulated in these leaves. Our results were obtained when floral induction was achieved either by vernalization or photoperiod signals, ruling out a mere environmental effect. We suggest that lily plants prepare themselves for the high‐energy‐demanding bloom by producing leaves with enhanced photosynthetic capacity, leading to an increase in soluble sugars. These novel findings introduce an adjacent affinity between photosynthesis and flowering and provide a nondestructive tool for identifying the plant's developmental stage—vegetative or reproductive. [ABSTRACT FROM AUTHOR]

Lisianthus (Eustoma grandiflorum), a leading plant in the cut flower industry, is scentless. Here we show that lisianthus flowers have potential to produce several fragrant benzenoid‐phenylpropanoids when substrate availability is not limited. To enable hyperaccumulation of substrates for the production of volatile benzenoid‐phenylpropanoids, lisianthus commercial hybrid "Excalibur Pink" was transformed via floral dipping with a feedback‐insensitive Escherichia coli DAHP synthase (AroG*) and Clarkia breweri benzyl alcohol acetyltransferase (BEAT), under constitutive promoters. The T1 progeny of "Excalibur Pink" plants segregated into four visual phenotypes, with pink or white colored petals and multiple or single petal layers. Interestingly, transformation with AroG* and BEAT caused no significant effect in the pigment composition among phenotypes, but did increase the levels of down‐stream fragrant volatile benzenoids. All the transgenic lines exclusively accumulated methyl benzoate, a fragrant benzenoid, either in their petals or leaves. Furthermore, feeding with benzyl alcohol resulted in the accumulation of two novel benzenoids, benzyl acetate (the product of BEAT) and benzoate, as well as a dramatic increase in the concentrations of additional benzenoid‐phenylpropanoid volatiles. Presumably, the degree of benzaldehyde overproduction after benzyl alcohol feeding in both leaves and flowers revealed their reverse conversion in lisianthus plants. These findings demonstrate the concealed capability of lisianthus plants to produce a wide array of fragrant benzenoid‐phenylpropanoids, given high substrate concentrations, which could in turn open opportunities for future scent engineering. [ABSTRACT FROM AUTHOR]

Summary: A bulb is a whole plant condensed into an underground organ. A geophyte's bulb comprises both food reserves and important developmental history that may affect its whole growth. In Easter lily (Lilium longiflorum), bulb size is associated with the plant's flowering pathway – vernalization or photoperiod – and also affects sprouting, flower quality and abortion rate. The aim of this study was to investigate the reasons for the major physiological differences between large and small bulbs. Lily bulbs start their development from secondary meristems along the stem, with large bulbs being heavier and bear more scales than small ones. Peeling the outer scales of a large bulb converts its physiological responses into those of a small bulb, implying that the physiological discrepancies in plants developing from large or small bulbs are mediated by factors inherent to the bulb. We therefore performed broad analyses of the metabolite composition in the scales of bulbs subjected to temperature regimes affecting further plant development. We found a striking association between the level of glycerol, a primary metabolite mostly synthesized in the outer scales, and a delay in sprouting and flowering time, and reduction in abortion rate. Exogenous glycerol application to the bulbs before planting corroborated these results. Moreover, transcriptome analyses showed that flowering‐promoting gene expression was downregulated in the bulb after glycerol treatment, while potential flowering inhibitor as well as a dormancy‐related gene expressions were upregulated. Based on these studies, we postulate that glycerol is a major factor influencing both vegetative and reproductive development in lily. Significance statement: In lily, bulb size is linked with the plant's flowering mechanism, vernalization or photoperiod, and affects important parameters during plant development. We show that glycerol, which is mainly produced in large bulbs, is strongly associated with physiological differences between large and small bulbs and is a major factor influencing both vegetative and reproductive development in lily. [ABSTRACT FROM AUTHOR]

Summary: The adaptation of the Agrobacterium‐mediated floral‐dipping technique is limited, to date, to a small number of plants. In this paper, we present the efficient transformation of one of the leading plants in the cut flower industry, lisianthus (Eustoma grandiflorum). This method is approximately 18 months shorter than the known tissue culture‐based transformation. The Excalibur Pink cultivar and two additional breeding lines, X‐1042 and X‐2541, were transformed using three different marker genes (benzyl alcohol acetyltransferase (BEAT) originating from Clarkia breweri, the feedback‐insensitive bacterial gene AroG*, and the empty pART27 vector expressing a kanamycin‐resistance cassette (nptII)). Genomic transformation was successful in all tested cases with transformation efficiency ranked from 0.2 to 2.9%, which is well in the range of results from Arabidopsis studies. Unlike Arabidopsis, in which floral‐dipping transformation was efficient only at a pre‐anthesis stage before ovary sealing, lisianthus flowers were transformed when dipping occurred 4 days pre‐anthesis or 3−5 days post‐anthesis with 1.5 and 3.7% efficiencies, respectively. Post‐anthesis transformation occurred when the flower ovaries were sealed. Flower dipping of Excalibur Pink flowers with fluorescent Agrobacterium containing a GFP marker gene demonstrated Agrobacterium entrance into the sealed flower ovary through the open stigma and style tube. In this study, we demonstrated floral‐dipping transformation of a commercial plant, lisianthus Excalibur Pink, occurring after sealing of the ovaries, probably via the stigma and wide open style tunnel. Significance Statement: Here we present successful Agrobacterium‐mediated genetic transformation of lisianthus via flower‐dipping. A unique finding of this study, is that successful transformation was achieved post‐anthesis, when lisianthus flower ovules are completely sealed, in contrast to the findings in Arabidopsis, suggesting possible entrance of the Agrobacterium through the flower style tube. [ABSTRACT FROM AUTHOR]

Lilium×formolongi is a facultative long-day (LD) plant. Aiming to dissect the molecular regulation of the photoperiodic pathway, largely unknown in Lilium, we explored the CONSTANS / FLOWERING LOCUS T (CO/FT) module, a major regulatory factor in the external coincidence model of the photoperiodic flowering pathway in lily. We identified eight CONSTANS-LIKE (COL) family members in L.×formolongi, which could be divided into three types, according to their zinc-finger (B-box) protein domains. Type I included only LfCOL5, containing two B-box motifs. Type II contained six LfCOLs members that had only one B-box motif. Type III contained only LfCOL9 that showed a normal B-box and a second divergent B-box motif. Phylogenic analyses revealed that LfCOL5 was the closest to Arabidopsis CO. LfCOL 5, LfCOL6 and LfCOL9 were up-regulated at the flowering induction stage under LDs, coinciding with an increase in LfFT1 expression. LfCOL5, LfCOL6 and LfCOL9 also showed obvious diurnal expression pattern for 3 d under LDs. However, under short-day (SD) conditions, the expression patterns of LfCOL5, LfCOL6 and LfCOL9 were variable and complex, with regard to the developmental stages and circadian rhythm. LfCOL5, LfCOL6 and LfCOL9 complemented the late flowering phenotype of the co mutant in Arabidopsis. Taken together, the results suggest that LfCOL5, LfCOL6 and LfCOL9 are involved in triggering flowering induction under LDs. LfCOL6 and LfCOL9 belong to types different from functional COL homologs in other plant species, illustrating the variation in phylogeny, evolution and gene function among LfCOL family members. [ABSTRACT FROM AUTHOR]

Large bulbs of Lilium longiflorum have an obligatory cold requirement to flower. Bulb cooling is widely used to induce and accelerate flowering. However, in‐depth investigations of the effect of bulb cooling on major landmarks of plant development are lacking. It has been demonstrated that low temperature induces carbohydrate degradation, yet integrative studies on metabolic changes occurring in the bulb are not available. We detected that cold exposure mainly hastened bulb sprouting, rather than floral transition or blooming. Metabolite profiling of cooled and non‐cooled bulbs was carried out, revealing cold‐induced accumulation of soluble sugars, lipids and specific amino acids, and a significant reduction in tricarboxylic acid (TCA)‐cycle elements. We observed that metabolic pathways located in the cytosol – including glycolysis, lipid synthesis and part of the gamma‐Aminobutyric acid (GABA) shunt – were enhanced by cold exposure, while mitochondrial metabolism – namely the TCA cycle – was reduced by cold. We suggest a physiological model accounting for this metabolic discrepancy. [ABSTRACT FROM AUTHOR]

This paper phenomenologically and qualitatively explores the relationship between humans and flowers as a relationship that throws light on the synergetic dynamics of embodied aesthetics. Its methods include qualitative description and thematic analyses of preferred flower types, as well as concept maps of the general term 'flower' by 120 students in Israel. The results revealed the interactive perceptual-compositional elements, as well as embodied, relational, and socially embedded elements of the aesthetic pleasure associated with flowers. Implications of this case study are generalized to understand the multiple and interactive components of embodied aesthetic experiences as a deep source of pleasure through interactive stimulation by and connection to the natural world. [ABSTRACT FROM AUTHOR]

Familiar fragrances usually induce positive mood states and elicit favorable evaluation. Relaxation is also widely thought to improve mood state. Yet experimental evidence on the effect of two different stimuli, fragrance smelling and breathing relaxation, on mood state, and fragrance evaluation is lacking. This study aimed to test (1) the effect of two familiar fragrances, lavender and myrtle, and two exotic fragrances, bergamot and ravensara, on perceived mood states before and after relaxation, (2) the effect of relaxation on perceived mood states for each fragrance, and (3) the effect of relaxation on fragrance evaluation as defined by adjectives. We hypothesized that mood states and assessment of the fragrances would differently be affected both in familiar vs. nonfamiliar fragrances and also before and after relaxation. Participants (n = 127) completed questionnaires on their mood states at baseline (T0). They were then presented with each of the four fragrances separately and asked to report on mood state and to assess the fragrances with adjectives before (T1) and after (T2) breathing relaxation. Analyses of the T0-T1 delta values of mood states by ANOVA repeated measures and post hoc comparisons showed that mood states were affected by fragrance smelling with no clear differences observed between familiar and exotic fragrances. The same analyses of T1-T2 values showed no differences in mood state after breathing relaxation and fragrance smelling. Fragrance assessment by adjectives indicated a non-conclusive trend for familiar and exotic fragrances. In sum, mood states induced by the fragrance smelling stimulus (T0-T1) were not changed by the addition of the second stimulus of relaxation (T1-T2), indicating that the former stimulus was stronger than the latter. On the other hand, the cognitive component represented by adjective-based assessment of fragrances was slightly modified by the relaxation stimulus. [ABSTRACT FROM AUTHOR]

Background: Vernalization is an obligatory requirement of extended exposure to low temperatures to induce flowering in certain plants. It is the most important factor affecting flowering time and quality in Easter lily (Lilium longiflorum). Exposing the bulbs to 4 °C gradually decreases flowering time up to 50% compared to non-vernalized plants. We aim to understand the molecular regulation of vernalization in Easter lily, for which we characterized the global expression in lily bulb meristems after 0, 2, 5, 7 and 9 weeks of incubation at 4 °C. Results: We assembled de-novo a transcriptome which, after filtering, yielded 121,572 transcripts and 42,430 genes which hold 15,414 annotated genes, with up to 3,657 GO terms. This extensive annotation was mapped to the more general GO slim plant with a total of 94 terms. The response to cold exposure was summarized in 6 expression clusters, providing useful patterns for dissecting the dynamics of vernalization in lily. The functional annotation (GO and GO slim plant) was used to group transcripts in gene sets. Analysis of these gene sets and profiles revealed that most of the enriched functions among genes up-regulated by cold exposure were related to epigenetic processes and chromatin remodeling. Candidate vernalization genes in lily were selected based on their sequence similarity to known regulators of flowering in other species. Conclusions: We present a detailed analysis of gene expression dynamics during vernalization in Lilium, covering several time points and accounting for biological variation by the use of replicates. The resulting collection of transcripts and novel isoforms provides a useful resource for studying the changes occurring during vernalization at a fine level. The selected potential candidate genes can shed light on the regulation of this process. [ABSTRACT FROM AUTHOR]

During the year 2002, two new diseases with unknown etiologies were detected in cucurbit crops in Israel. One disease was detected in squash fields throughout the country, while the second appeared in a single watermelon plot in the south, just outside the city of Elat. The infected watermelon plot was eradicated, but nonetheless the new disease spread throughout the country and today it is present in all the watermelon production areas. Both diseases were associated with elevated whitefly populations. Indeed, it was found that both are transmitted only by whiteflies, and are incited by two begomoviruses. Both viruses were cloned and sequenced, and were identified as Watermelon chlorotic stunt virus (WmCSV) and Squash leaf curl virus (SLCV). The host range of the Israeli WmCSV isolate (WmCSV-IL) was determined and resembles the host range of the three other known WmCSV isolates (from Yemen, Sudan, and Iran), but with a few differences. Although no genetic resistance to WmCSV was observed in cultivated watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai], resistance to the virus was found in a wild relative, colocynth (Citrullus colocynthis (L) Schrader). Nucleotide sequence comparisons revealed that WmCSV-IL is highly homologous to other WmCSV isolates, with the highest homology (nearly identical) to the isolate from Sudan. SLCV-IL host range was determined as well, and was also found to be similar to other SLCV isolates. However, following genome sequencing, it was found that due to two separate point mutations, two viral open reading frames (ORF) were altered. The AC2 ORF was extended by 129 nucleotides, while the BV1 ORF was reduced by 99 nucleotides. [ABSTRACT FROM AUTHOR]

Lilium candidum is a rare geophyte with a tall stem and large, fragrant, pure white flowers, found in Greece, Turkey, Syria, Lebanon, and Israel. It is an endangered species in the Israeli flora, with a high priority for conservation. Characterization and conservation of wild ecotypes are essential for preserving this important plant. We have established a collection of wild L. candidum ecotypes collected at four locations in Kelach Creek in Mount Carmel and in the Kziv Creek in the Galilee, and assessed flowering-related traits in plants growing in their natural habitats and under controlled conditions in Be'er Sheva for two consecutive years. Variation among locations was observed for flowering time and stem length, but not for the number of flowers per stem. Plants grown in the greenhouse flowered consistently several weeks earlier and produced more flowers per stem than under natural conditions. Morphological differences in flower shape between ecotypes from Kelach and Kziv Creek were apparent. The variation for flowering traits found in wild populations can be used for breeding purposes. [ABSTRACT FROM AUTHOR]

Abstract: In roses, bending of the peduncle during flower development – “bent peduncle phenomenon” (BPP) – results in the production of a series of developmental aberrancies. Detailed characterization of BPP revealed that the typical bending is intrinsically related to developmental features, i.e., the presence of an enlarged sepal appearing as a phylloid structure, floral organ conversions, fasciation of the stem and the higher incidence of BPP in axillary stems developing from BPP stems than from normal stems. The sclerenchymal tissue of BPP stems exhibited larger cells and thinner cell walls than those of normal stems, which may facilitate the bending process. BPP-like bending could be induced by external auxin application and inhibited by auxin transport inhibitors. Thus, in BPP auxin appears to be involved in differential growth, thereby inducing bending. However, there were no differences in endogenous IAA content between the upper and lower sides of bent peduncles, indicating that the asymmetric IAA distribution may be transient. This study strongly suggests that BPP is a developmental process, occurring during the meristematic stage of flower formation, possibly involving auxin distribution, which affects stem bending and fasciation. [Copyright &y& Elsevier]

Abstract: Protocols for in vitro regeneration and production of in vitro-propagated plants and a transformation system were developed for Mirabilis jalapa (Nyctaginaceae). Among the types of explants and the different media tested, consistent shoot regeneration was obtained only from nodal segments grown in a regeneration medium consisting of Murshashige and Skoog medium supplemented with 2mgl−1 6-benzyladenine, 2mgl−1 zeatin and 1mgl−1 indole acetic acid. Regeneration efficiency was dependent on the type of plant – white or pink flowers – used as the source of explants. Stable transformation was obtained following inoculation of nodal segments with Agrobacterium tumefasciens strain EHA105, which harbours the binary plasmid pAD1339 containing both nptII and gus genes under the control of the 35S promoter. Transformation was confirmed by PCR and Southern blot analysis of genomic DNA from mature regenerated plants. β-Glucuronidase (GUS) activity was observed only in tissues regenerated from in vitro-grown plants and not in tissues originating from greenhouse-grown plants. GUS expression was not uniform in regenerated leaves and showed a chimera pattern. [Copyright &y& Elsevier]

Floral transition was studied in lisianthus [Eustoma grandiflorum (Raf.) Shinn.] plants grown in a greenhouse at two planting times (winter and summer) under two photoperiod regimes: long day (LD) and short day (SD), 16 h/8 h and 8 h/16 h (light/dark), respectively. Morphological analyses of the flower meristem of the lisianthus cultivar ‘Heidi Deep Blue’ revealed three distinct stages of development: (1) sepal primordia, (2) petal and stamen primordia (almost simultaneously), and (3) carpel primordia. The appearance of sepal primordia was taken to mark the floral transition stage. Floral transition was hastened in summer-grown plants and under LD treatment, as expressed by a reduction in both the number of nodes and the time from planting. Stem length from base of plant to floral meristem, as measured at floral transition, was similar in all treatments, regardless of the number of nodes produced. At both planting dates, SD induced a higher number of flowers per inflorescence than LD. This report thus describes the direct effect of environmental factors on floral transition in lisianthus. [Copyright &y& Elsevier]

Lilium candidum L., known as Madonna, meadow, or white lily, is a bulbous plant from the Liliaceae family, originating in the Middle East. L. candidum has been abundantly used in folk medicine since ancient times to relieve a variety of ailments, including age-related diseases, burns, ulcers, and coughs. The aim of this article is to investigate the anti-inflammatory and anti-diabetic activities of L. candidum extracts and its active phytochemicals. Some active volatile phytochemicals were identified using gas chromatography–mass spectrometry (GC-MS) analysis. Significant (p < 0.001) anti-diabetic properties of the extracts kaempferol, linalool, citronellal, and humulene were demonstrated by an elevation in glucose uptake by adipocytes. The significant (p < 0.01) effect of the plant extracts kaempferol, citronellal, and humulene on the secretion of pro-inflammatory cytokines interleukin 6 (IL-6) and interleukin 8 (IL-8) was demonstrated using enzyme-linked immunosorbent assay. Altogether, L. candidum and its rich collection of phytochemicals hold promising medicinal potential, and further investigations of its therapeutic prospects are encouraged. [ABSTRACT FROM AUTHOR]

In Lilium longiflorum , vernalization is both an obligatory requirement and the major factor affecting flowering time, however, little is known about the molecular regulation of this mechanism in Lilium and other flowering bulbs. Exposure of L. longiflorum bulbs to 9 weeks at 4 °C greatly promoted stem elongation within the bulb, floral transition and flowering. Subtraction libraries of vernalized (V) and non-vernalized (NV) bulb meristems were constructed. 671 and 479 genes were sequenced, from which 72 and 82 proteins were inferred for the NV–V and the V–NV libraries, respectively. Much lower transcription levels and putative gene functions were recorded in the NV–V libraries compared the V–NV libraries. However, a large number of genes annotated to transposable elements (TEs), represented more than 20% of the sequenced cDNA were expressed in the NV–V libraries, as opposed to less than 2% in the V–NV libraries. The expression profile of several genes potentially involved in the vernalization pathway was assessed. Expression of LlSOC1 , the lily homologue of SUPPRESSOR OF OVER-EXPRESSION OF CO1 ( SOC1 ), an important flowering gene in several plant species, found in the V–NV library, was highly up-regulated during bulb meristem cold exposure. The subtraction libraries provided a fast tool for relevant gene isolation. [ABSTRACT FROM AUTHOR]

Abstract: Crude ethanol extracts from Ficus benjamina leaves strongly inhibit Herpes Simplex Virus 1 and 2 (HSV-1/2) as well as Varicella Zoster Virus (VZV) cell infection in vitro. Bioassay-guided fractionation of the crude extract demonstrated that the most efficient inhibition of HSV-1 and HSV-2 was obtained with the flavonoid fraction. The present study was aimed to further isolate, purify and identify substances with potent antiviral activity from the flavonoid fraction of F. benjamina extracts. Flavonoids were collected from the leaf ethanol extracts through repeated purification procedure and HPLC analysis. The antiviral activity of each substance was then evaluated in cell culture. Three known flavone glycosides, (1) quercetin 3-O-rutinoside, (2) kaempferol 3-O-rutinoside and (3) kaempferol 3-O-robinobioside, showing highest antiviral efficiency were selected and their structure was determined by spectroscopic analyses including NMR and mass spectrometry (MS). These three flavones were highly effective against HSV-1 reaching a selectivity index (SI) of 266, 100 and 666 for compound 1, 2 and 3, respectively, while the SI of their aglycons, quercetin and kaempferol amounted only in 7.1 and 3.2, respectively. Kaempferol 3-O-robinobioside showed similar SI to that of acyclovir (ACV), the standard anti-HSV drug. Although highly effective against HSV-1 and HSV-2, these flavone glycosides did not show any significant activity against VZV. [Copyright &y& Elsevier]

Abstract: Lisianthus (Eustoma grandiflorum) is an ornamental plant with beautiful but scentless flowers. In an attempt to induce a fragrance in their flowers, lisianthus plants were transformed with the Clarkia breweri gene coding for benzyl alcohol acetyltransferase (BEAT), catalyzing the synthesis of the volatile compound benzyl acetate under the regulation of the CaMV35S promoter. An external supply of benzyl alcohol induced five to seven times higher production of benzyl acetate in detached flowers and leaves of transgenic lisianthus plants, compared to non-transformed plants. No benzyl acetate was detected in tissues of both control and transgenic plants fed with water. When fed with additional alcoholic compounds, i.e. hexanol, benzyl alcohol, isoamyl alcohol, phenethyl alcohol, and cinnamyl alcohol, assumed to be used as substrates by BEAT, transgenic in vitro-grown lisianthus plantlets produced significantly higher levels of acetates than control plants. These results demonstrate the possibility of producing substrate-dependent acetates in transgenic lisianthus plants, which could lead to induction of new aromas. [Copyright &y& Elsevier]

• Vernalization is a major pathway regulating flowering time in L. candidum. • Cold exposure at different seasons induces either flowering enhancement or delay. • The effect of cold exposure on flowering is determined by the meristem's developmental stage. Madonna lily (Lilium candidum) is a flowering geophyte growing wild in Israel and in the neighboring region. In view of its holly character in the Christian culture, L. candidum has a great commercial potential as an ornamental crop. However, knowledge regarding its cultivation and the control of its flowering time is very limited. In this study, we aimed to define external factors affecting L. candidum flowering and characterized the developmental stages of the shoot apical meristem (SAM), under different temperature and photoperiod regimes. We found that in most cases, bulb or plant exposure to low temperature (4 °C, forcing) hastened floral transition and flowering in a quantitative manner, whereas day length had a negligible effect on these traits. These results suggest that vernalization is a major pathway regulating flowering time in L. candidum. We also characterized a novel phenomenon in which exposure of the bulb to low temperature led to a delay in bolting and flowering until the following season. We showed that the ability of a bulb to perceive cold exposure as signal for flowering hastening or as a delay was dependent on the SAM's developmental stage and was related to the season. During the summer, cold exposure applied to the SAM at the juvenile phase results in growth inhibition, while from the fall onward, when the meristem has reached its vegetative adult phase, cold exposure promotes bolting and flowering, according to the classic vernalization response. Exposure of the juvenile bulb to 12 °C promotes the transition of the SAM from juvenile to vegetative adult. In conclusion, we showed cold exposure of bulbs at the juvenile phase induced the inhibition of the bolting and flowering, while bulb cold exposure of bulbs at the vegetative adult stage promoted flowering. This study sheds light on the development and flowering physiology of L. candidum and can have applied outcomes for its cultivation as a cut flower crop. [ABSTRACT FROM AUTHOR]

In deciduous fruit trees, the effect of chilling on flowering has mostly been investigated in the “indirect flowering” group, characterized by a period of rest between flower bud formation and blooming. In the present study, we explored the effects of chilling and chilling deprivation on the flowering of Ziziphus jujuba , a temperate deciduous fruit tree belonging to the “direct flowering” group, in which flower bud differentiation, blooming and fruit development occur after dormancy release, during a single growing season. Dormancy release, vegetative growth and flowering time in Z. jujuba cv. Ben-Li were assessed following several treatments of chilling. Chilling treatments quantitatively decreased the timing of vegetative bud dormancy release, thereby accelerating flowering, but had no effect on the time from dormancy release to flowering. Trees grown at a constant temperature of 25 °C, without chilling, broke dormancy and flowered, indicating the facultative character of chilling in this species. We measured the expression of Z. jujuba LFY and AP1 homologues ( ZjLFY and ZjAP1 ). Chilling decreased ZjLFY expression in dormant vegetative buds but had no effect on ZjAP1 expression, which reached peak expression before dormancy release and at anthesis. In conclusion, chilling is not obligatory for dormancy release of Z . jujuba cv. Ben-Li vegetative buds. However, the exposure to chilling during dormancy does accelerate vegetative bud dormancy release and flowering. [ABSTRACT FROM AUTHOR]

Abstract: The effects of shading on lisianthus (Eustoma grandiflorum) floral transition, plant development, flower yield and quality, and content of starch and soluble sugars were assessed in three cultivars, over two consecutive years. Shading nets affording 67% or 88% reduction in light intensity, were fitted at planting in the greenhouse for periods ranging from 3 to 8 weeks. Meristem morphology at floral transition was characterized by apical meristem widening and the appearance of two bract primordia. Floral transition time was affected by cultivars, but in general, longer and heavier shade treatments delayed floral transition; the longest delay (6 weeks) being recorded in Mariachi White under 88% shade for 7 weeks or under a combined shade treatment of 88% for 3 weeks followed by 67% for 5 weeks. Despite interactions between cultivar and shade treatment, consistent trends were discerned: the heaviest and most prolonged shading reduced yield (up to 40%), cut stem length (up to 15%), and number of flower buds/stem (up to 26%), within cultivar. Total carbohydrates levels were very low, and it is questionable whether changes observed in carbohydrate quantity following shade treatments had any effect on plant growth or flower yield. Rather, it appears that lisianthus is very dependent on current photosynthesis, so that even a brief shading interlude could reduce branching and flower quality. It may be concluded that the intensive shading usually applied is detrimental for lisianthus. [Copyright &y& Elsevier]