Search Results (51)

Background: The GhA01EP1 gene in upland cotton encodes an epidermal-specific secreted glycoprotein, whose functional characterization remains unexplored beyond our initial discovery of its water deficit resistance association. Therefore, we further designed experiments to investigate the functional role of GhA01EP1. Methods: We sequenced and analyzed the transcriptomes of wild-type (Col-0) and GhA01EP1-transgenic Arabidopsis thaliana. The differences in morphological and biochemical indicators were examined. In addition, the proteins interacting with GhA01EP1 in Arabidopsis were screened using a glutathione-S-transferase pull-down assay. Results: The GhA01EP1-transgenic Arabidopsis plants flowered earlier, produced more branches, and had a higher seed yield than Col-0. Transcriptome analysis revealed that differentially expressed genes detected in the comparison of GhA01EP1-transgenic and Col-0 Arabidopsis under the water treatment (the control) were associated especially with circadian rhythm regulation, photoperiodic flowering reaction, hormone metabolism, glyoxalase I synthesis, antioxidant pathway, branching development, and carbon-nitrogen allocation. Under water-sufficient or water-deficient treatments, the glyoxalase I activity and lignin content of GhA01EP1-transgenic Arabidopsis were significantly higher. Under water deficit stress, the malondialdehyde and starch contents were significantly lower, while peroxidase activity and protein content were significantly higher than those of Col-0. Conclusions: GhA01EP1 synergistically improved the precocity, water deficit tolerance, and seed yield of GhA01EP1-transgenic Arabidopsis. Analysis of GhA01EP1 function provides a molecular basis for breeding improved cotton varieties. Full article

In the present study, groups of 10 adult males from wild-type strain Drosophila melanogaster Canton-S and corresponding mutant tab2^201Y were continuously observed using automatic digitization. Data based on instantaneous movement and cumulated movement positions were obtained for micro-areas providing space for resources (food and moisture) and for activity (edge area and intermediate area [between edge and center-diffusion areas]) within the observation arena for 24 h. The results confirmed the natural tendency of local aggregation among individuals within the observation arena (14 cm × 14 cm) at a relatively low density of ten individuals. For Canton-S, temporal cooccurring patterns among different parameters were observed as time progressed, with two primary patterns identified in the resource supply areas: single peak and double peaks. The single peak was observed with maximum speed and I-index, indicating minimum degree of isolated individuals from groups, during the transition from the photoperiod to the scotoperiod. The double peaks occurred before (mid-to-late photoperiod) and after (end of scotoperiod) the single peak, co-occurring temporally with a number of parameters including duration rates, stop number (total occurrence of pauses), stop time (total duration of pauses), mean crowding (MC), and social space index (SSI), indicating local aggregations for feeding in accordance with maximum durations in resource supply areas. Temporally cooccurring trends in parameters were also found with the stop number and SSI in micro-areas associated with activity, indicating that short pauses were needed to keep balance between attraction and repulsion between nearby individuals. Overall, the measured parameters varied depending on the micro-area, light phase, and strain. In particular, behavioral differences were observed for tab2^201Y, including an increase in speed, especially in the areas related to activity during the scotoperiod. Between strains, behavioral differences in the measured parameters were observed less for tab2^201Y than Canton-S. Full article

The predatory function and numerical responses of natural enemy insects are critical for evaluating their biological control potential, particularly in understanding pest suppression mechanisms and ecological adaptability. Here, we examined the predation capacity of Tytthus chinensis Stål (Hemiptera: Miridae) on Sogatella furcifera eggs under laboratory conditions (24 ± 1 °C, 12:12 h light:dark photoperiod, 75% humidity). Functional response experiments were conducted at different prey densities (3, 4, 10, 20, and 30 eggs/day), and life table parameters were established to evaluate the effects of prey density on the development, reproduction, and population dynamics of T. chinensis. The daily average predation of nymphs significantly increased with age, and their functional responses fitted the Holling Type II response. In the adult stage, the daily average predation of females was significantly higher than that of males, and males had a higher a/T_h ratio, which reflected sex-specific predation strategies. Prey density significantly influenced survival, reproduction, and population dynamics. The minimum prey density required for population stability was 4 eggs/day, and survival and reproduction rates markedly increased at 10 eggs/day. At 30 eggs/day, females reproduced earlier, and the lifespan of males was shortened. These findings confirm the strong pest control ability of T. chinensis and highlight the critical role of S. furcifera egg density in regulating the population dynamics of T. chinensis. Full article

Linum mulleri is an endemic taxon of southwestern Sardinia (Italy), categorised as Endangered (EN) on the IUCN Red List and included in Annexes II and IV of the Habitats Directive (92/43/EEC) as priority species for conservation. This study investigated the germination ecophysiology of L. mulleri and the possible presence of dormancy by using 7000 seeds, providing useful information for conservation strategies. The germination response of fresh seeds was evaluated under different temperatures, photoperiods, pre-treatments [cold stratification (C); warm stratification (W); W+C; C+W+C; dry after-ripening (DAR)], and different gibberellic acid (GA₃) concentrations. L. mulleri germinated under controlled conditions, particularly at 15 and 20 °C, while germination percentages (GP) never exceeded 5% at 5 and 30 °C. C and C+W+C induced secondary dormancy, delaying germination, whereas W, DAR, and GA₃ stimulate it. Light and dark incubation showed no significant differences in regards to GP. W, DAR, and 250 mg/L GA₃ effectively overcame physiological dormancy (PD), expanding the germination temperature range to below 10 and above 25 °C. These responses suggested type 3 non-deep PD, as germination temperatures extended from a moderate range to both low and high temperatures. Analyzing 7000 seeds provided crucial information regarding dormancy and germination strategies, supporting both ex situ and in situ conservation efforts. Full article

The postnatal development of gonadal glands in seasonal breeders, particularly small rodent species, is influenced by photoperiodic patterns. However, little research has been conducted on the effects of pattern similarity and age differentiation especially in molecular features. This study compares the postnatal development of gonadal glands and the expression of hypothalamic genes related to reproductive regulation in male offspring of Brandt’s voles (Lasiopodomys brandtii) born under three types of changing photoperiodic patterns: increasing long photoperiod (ILP, 12 h + 3 min/day), natural increasing long photoperiods (NLPs), and decreasing short photoperiods (DSPs, 12 h − 3 min/day), as well as in their paternal voles exposed to these patterns at the same period. Results indicate that over the course of 12 postnatal weeks, gonadal development, including organ masses and serum testosterone levels, exhibited similar profiles between the ILP and NLP groups, which were significantly higher than those observed in DSP offspring. Hypothalamic type 3 iodothyronine deiodinase (Dio3) exhibited significantly higher expression in the DSP group from postnatal week 4 to 8 compared to the other two groups. These physiological and molecular differences gradually decreased with age in offspring, but were never observed in the paternal voles, indicating divergent photoperiodic responses between the two ages. The synchronous profiles observed between hypothalamic Dio3 expression and gonadal activities underscore its crucial role in interpreting photoperiodic signals and regulating gonadal development in Brandt’s voles. Full article

To investigate the effects of photoperiods on the growth and muscle quality indicators of grass carp (Ctenopharyngodon idella), 225 fish (109.65 ± 3.62 g) were randomly assigned into five different photoperiod groups (0L:24D, 8L:16D, 12L:12D, 16L:8D, and 24L:0D). The experiment spanned a 75-day period, after which sampling and analysis were performed. Compared with the 0L:24D and 8L:16D groups, the 12L:12D and 16L:8D groups significantly promoted the growth of grass carp (p < 0.05). The texture parameters of the muscle in the 0L:24D and 16L:8D groups were significantly greater than those in the 12L:12D group (p < 0.05). The crude protein content was significantly higher in the 12L:12D and 16L:8D groups (p < 0.05). The amino acid content and muscle fiber characteristics, as well as the mRNA levels of myostatin (mstn), myogenic factor 5 (myf5), type I collagen α1 (col1α1), and α2 (col1α2), along with the hydroxyproline and collagen contents, were all significantly influenced by the photoperiod (p < 0.05). The lysine (Lys), aspartic acid (Asp), and alanine (Ala) contents in the muscle and muscle fiber density of grass carp reached the highest levels under the 16L:8D treatment (p < 0.05). Collectively, these results indicate that a 16L:8D photoperiod is optimal for enhancing both the growth and muscle quality indicators of grass carp. The findings of this study offer valuable scientific references for the precise regulation of grass carp quality when using a photoperiod, and they are anticipated to foster the further development and optimization of strategies for improving grass carp quality. Full article

The circadian clock plays a vital role in facilitating plant adaptation to rhythmically changing environmental factors. Pseudo-response regulators (PRRs) are key components regulating the plant circadian clock and have been extensively characterized in model plants. However, the PRRs in the tea plant have not been comprehensively studied. In this study, seven CsPRRs were cloned from the tea plant. Domain, phylogenetic evolution, gene structure, motifs, and cis-acting element analysis revealed their sequence characters and suggested that the first subgroup members, CsPRR1a, 1b, 5a, 5b, 7, and 37, may be responsible for circadian rhythm regulation and abiotic stress responses, while the second subgroup member, CsPRR2, may be involved in development and chloroplast function regulation. Most CsPRRs showed relatively higher expression in flowers, implying their potential roles in photoperiod-regulated flower induction. Moreover, rhythmic expression of CsPRR7, 5b, 5a, 37, 1b, and 1a was observed under long-day conditions in a sequential manner. Additionally, CsPRRs were differently induced/inhibited by cold, heat, and drought stresses in tissue-specific and photoperiod-related manners. A stronger cold induction of CsPRRs was observed under long-day conditions than under short-day conditions. And, among the two tested tissues, changes in the expression of CsPRRs caused by various stresses were more obvious in young shoots. Studies using a floriferous cultivar (FDDB) and an oliganthous cultivar (PYTZ) implied that CsPRRs also played crucial roles in tea-plant flower induction. This study presents the first comprehensive analysis of CsPRRs in the tea plant, providing vital information for further elucidation of CsPRR functions. It also suggests that tissue type and photoperiod conditions should be taken into consideration when conducting gene function studies in the tea plant. Full article

Land plants grow throughout their life cycle via the continuous activity of stem cell reservoirs contained within their apical meristems. The shoot apical meristem (SAM) of Arabidopsis and other land plants responds to a variety of environmental cues, yet little is known about the response of meristems to seasonal changes in day length, or photoperiod. Here, the vegetative and reproductive growth of Arabidopsis wild-type and clavata3 (clv3) plants in different photoperiod conditions was analyzed. It was found that SAM size in wild-type Arabidopsis plants grown in long-day (LD) conditions gradually increased from embryonic to reproductive development. clv3 plants produced significantly more leaves as well as larger inflorescence meristems and more floral buds than wild-type plants in LD and short-day (SD) conditions, demonstrating that CLV3 signaling limits vegetative and inflorescence meristem activity in both photoperiods. The clv3 phenotypes were more severe in SDs, indicating a greater requirement for CLV3 restriction of SAM function when the days are short. In contrast, clv3 floral meristem size and carpel number were unchanged between LD and SD conditions, which shows that the photoperiod does not affect the regulation of floral meristem activity through the CLV3 pathway. This study reveals that CLV3 signaling specifically restricts vegetative and inflorescence meristem activity in both LD and SD photoperiods but plays a more prominent role during short days. Full article

Tulips are among the most famous plants that are used mainly as ornamental cut flowers. Although widely cultivated, they are mainly reproduced asexually, and knowledge of their sexual reproduction is imperfect, especially in regard to botanical tulips. The aim of the present study was to investigate the temperature effect on seed germination of the Near Threatened wild-growing Greek subendemic plant Tulipa saxatilis (Liliaceae) and to define its seed dormancy type. Seed germination was facilitated by bioclimatic profiling generated with R software (version 4.3.3) connecting its natural distribution points with open access precipitation and temperature data, and it was assessed upon incubation in controlled growth chambers at five constant temperatures (5, 10, 15, 20 and 25 °C) under a 12:12 light–dark photoperiod. The seeds were dependent on temperature for germination and germinated only within a very narrow range of relatively low temperatures (5–15 °C) and optimally at 10 °C (93%), corresponding to natural winter temperatures and precipitation profiles. Increase in the incubation temperature at 20 and 25 °C resulted in no germination. The treatment of seeds with gibberellic acid (GA₃) at two different concentrations (500, 1000 mg·L⁻¹) did not widen the temperature range for seed germination. The seeds of T. saxatilis initially presented an underdeveloped embryo, and significant embryo development was detected only at low temperatures (10 and 15 °C) with almost triple embryo length after one month, thus confirming the existence of complex morphophysiological seed dormancy. Moreover, germinated seeds (with and without GA₃) were planted in small-sized pots under greenhouse conditions, and the growth of bulblets was investigated in response to the application of commercially available chemical fertilizers, an integrated nutrient management scheme, and a biostimulant. The fertilization schemes affected the weight and length of the produced bulblets, whereas initial seed treatment with GA₃ negatively affected the growth (weight, length, and width) of the produced bulblets. Full article

Zinc oxide (ZnO) particles have recently received attention in different agriculture sectors as new technologies and practices are entering into force with limited adverse effects on the environment. However, various works have reported both positive or negative effects on plants. The present study focused on an evaluation of the effects of four different new micro- and nano-sized ZnO particles (namely, Desert Roses (DRs), MultiPods (MPs), NanoFlakes (NFs), and NanoParticles (NPs)) on the seed germination traits of Ocimum basilicum L., Lactuca sativa L., and Lepidium sativum L. ZnO particles were applied at concentrations of 12.5 ppm, 25 ppm, and 50 ppm. Seeds moistened with deionized water were used as a control. All the particles were characterized by field emission scanning electron microscopy, and their production of Reactive Oxygen Species (ROS) under seed germination conditions was evaluated through electron paramagnetic resonance spectroscopy. Seeds of each species were put on filter paper under controlled conditions in both dark and light photoperiods. In this bioassay, the final germination percentage (FGP), early root length, and index of germination were evaluated. The results showed a wide variability of response to the type and concentration of ZnO particles and to the applied photoperiod of the three studied species. O. basilicum FGP increased when treated with NPs and DRs already at the lowest concentration and especially in light conditions with values significantly superior to those of the control (71.1%, 69.4%, and 52.2%, respectively). At higher concentrations, phytotoxicity on root length was observed, with a reduction of circa 30% in comparison to untreated seeds. On the contrary, in L. sativum, a phytotoxic effect was seen in radicle length with all the used ZnO particles and concentrations. L. sativa seeds did not show significant effects due to the type of particles, with a reduction in FGP only at higher concentrations and particularly in light conditions. Upon light irradiation, different levels of ROS were counted by the application of ZnO particles. DRs produced the highest amount of DMPO-OH adduct (up to 2.7 × 10⁻⁵ M) followed by the NP type (2.0 × 10⁻⁵ M). Taking together all these findings, the seeds’ coat morphology, their ability to absorb ZnO particles, and the ROS production in light conditions are indeed crucial players in the application of these formulations in seed germination. Full article

The oil sunflower is an important oil crop and ornamental plant. Flowering time affects the environmental adaptability and final yield of oil sunflowers. Floral induction is one of the important events that determines subsequent reproductive growth and seed setting, but there has been no systematic study on the regulation of gene expression during the transition from vegetative growth to reproductive growth in oil sunflowers. In this study, an oil sunflower mutant displaying early flowering (ef) was obtained by heavy ion beam irradiation. This mutant had a stable genetic trait, and its flowering time was 15 days earlier than the wild type (WT) in the field. The histology result showed that the ef mutant induced floral meristem at 6-leaf stage earlier than WT. The shoot apical meristems (SAMs) of the ef mutant and WT at 4-leaf, 6-leaf, 8-leaf, 10-leaf and budding periods were collected for RNA sequencing. The results showed that the transition from the leaf meristem to the floral meristem resulted in significant changes in the transcriptional landscape. Overall, 632, 1825, 4549, 5407 and 2164 differentially expressed genes (DEGs) were identified at 4-leaf, 6-leaf, 8-leaf, 10-leaf and budding periods, respectively. These DEGs were mainly enriched in biological pathways, including plant hormone signal transduction, carbon metabolism, protein processing in endoplasmic reticulum, secondary metabolism, and photosynthesis. We also found significant differences in the expression levels of starch and sucrose metabolism-related genes in the ef mutant and WT, indicating that sugar signaling plays an important role in the early flowering of oil sunflowers, especially SUC9 and sugar synthesis and degradation enzyme genes. In addition to hormone and sugar signals, flowering integration genes SOC1, AP1, FUL and LFY were upregulated in the ef mutant, and genes in photoperiod, aging, autonomous and temperature pathways were also involved in the regulation of floral transition. The results showed that plant hormones, sucrose metabolism, and flowering genes synergistically cause the early flowering of oil sunflowers. Our study provided important information for understanding flowering and is helpful for the genetic improvement of sunflowers. Full article

SPL transcription factors affect plant growth and development, including blooming and photoperiod control. The investigation began with transcriptome data screening of 28 JrSPL genes in walnut (Junglans regia L.) ‘Wen185’. These genes were discovered on all chromosomes except 6 and 15. Phylogenetic study divides the 28 JrSPL genes into five groupings. The biggest cluster, cluster IV, has 12 JrSPL genes. The expression of JrSPL genes in different tissues was investigated by qRT-PCR. JrSPL02 gene expression was greater in walnut female and male flower tissues than other genes. Subcellular localization has shown the JrSPL02 gene resides in the nucleus. Jre-miR156 may target JrSPL02’s 3′-UTR region, according to miRNA sequencing, RACE, and BiFC studies. Arabidopsis plants expressing the JrSPL02 gene flowered 3 days faster than the wild type, according to phenotypic observation. Transgenic lines had more stem branches and siliques than the control group but fewer rosette leaves. In summary, this study functionally analyses the metamorphosis of the miR156-SPL module during the blooming stage and the underlying mechanisms that govern early fruiting in early-fruiting walnuts in Xinjiang. Full article

(1) Background: Anthocyanins, the main pigments in plants, are influenced by both temperature and photoperiod. However, the specific mechanisms underlying anthocyanin accumulation in tea plants in response to these two environmental factors remain unclear. (2) Methods: This study subjected potted ‘Ziyan’ tea plants to four types of day-length and temperature treatments (HL (28 °C, 16 h), HS (28 °C, 8 h), LL (18 °C, 16 h), and LS (18 °C, 8 h)), and then conducted targeted metabolomic and transcriptomic analyses of the samples. (3) Results: Long photoperiods and low temperatures both promoted anthocyanin accumulation in the new shoots of the tea plants. Furthermore, the enhancing effects of these two environmental factors on anthocyanin accumulation are additive and exhibit interactive effects. Through a combined analysis of metabolomics and transcriptomics, five key differentially accumulated metabolites (DAMs) and twenty-two key differentially expressed genes (DEGs) were identified, the latter being found to participate in the regulation of anthocyanin biosynthesis pathways under varying light and temperature conditions. In summary, extended photoperiods primarily increase the content levels of ten metabolites, including cyanidin and naringenin-7-O-glucoside, by upregulating CHS, F3H, and ANS genes. In contrast, low temperatures primarily enhance the synthesis of seven anthocyanins, including cyanidin and cyanidin-3-O-rutinoside, by upregulating the ANS and UFGT genes. (4) Conclusions: Collectively, the differences in the expression levels of CHS, F3H, ANS, and UFGT might be responsible for ‘Ziyan’ tea plants’ purple shoot coloration, providing important data towards the discovery of candidate genes and molecular bases controlling the purple leaves of these tea plants under varied photoperiods and temperatures. Full article

Soil salinity is a well-known abiotic factor affecting the germination and seedling growth of various plant species. Therefore, we evaluated the effects of different chloride salts (NaCl, KCl and MgCl₂) and sulfate salts (Na₂SO₄, K₂SO₄ and MgSO₄) on the seed germination and early seedling growth of two important ethnomedicinal shrubs of North Africa and the Mediterranean basin (Ballota hirsuta and Myrtus communis). Seeds of these species were subjected to five salinity levels (0–100 mM) and incubated at 20 °C under a light regime (12 h photoperiod). Both species demonstrated their highest germination percentage under control conditions (i.e., without salinity). However, as salinity levels increased, the germination percentages for both species decreased, regardless of the type of salt used. Cations appeared to be more determinative than the anions in regulating the seed germination of both species. M. communis seeds displayed greater sensitivity to sodium (Na⁺) salts, especially when accompanied with chloride (Cl⁻) anions. At the higher salt concentrations (75 and 100 mM), Na⁺ salts had a more pronounced inhibitory effect on M. communis seedling growth compared to potassium (K⁺) and magnesium (Mg²⁺) salts. Conversely, Mg²⁺ salts were more detrimental to seedling growth in B. hirsuta. Based on our results, it can be concluded that both of these species are able to tolerate a moderate level of salinity. Overall, B. hirsuta may be a promising choice for rehabilitating the soils dominated by chloride salts, while M. communis could be utilized for restoring sulfate-dominated soils. Full article

The duration of the vegetative period is an important agronomic characteristic of cereal crops. It is mainly influenced by the Vrn (response to vernalization) and Ppd (response to photoperiod) genes. In this work, we searched for alleles of several known genes of these two systems of response to external conditions in 15 accessions of Aegilops tauschii Coss. (syn. Ae. squarrosa L.), with the aim of studying the impact these alleles have on the vegetative period duration and growth habit. As a result, three allelic variants have been found for the Vrn-D1 gene: (i) one intact (winter type), (ii) one with a 5437 bp deletion in the first intron and (iii) one previously undescribed allele with a 3273 bp deletion in the first intron. It has been shown that the spring growth habit of Ae. tauschii can be developed due to the presence of a new allele of the Vrn-D1 gene. Significant differences in expression levels between the new allelic variant of the Vrn-D1 gene and the intact allele vrn-D1 were confirmed by qPCR. The new allele can be introgressed into common wheat to enhance the biodiversity of the spring growth habit and vegetative period duration of plants. Full article