Short Days Research Articles

Response to selection through introgression breeding in onion (Allium cepa L.)

Development of suitable varieties of onion with high yieldas well as good shelf life through crossing between longand short-day onion was carried out at the Research Farmof ICAR-Directorate of Onion and Garlic Research,Rajgurunagar, Pune in collaboration with ICAR-CITH,Srinagar. A total of 135 crosses were made between available15 exotic onion varieties and 9 short day lines at ICARCITH,Srinagar. The crosses were evaluated in their F2generation and further selection were continued up to F5generation. The experiment was laid out in randomized blockdesign with three replications during rabi seasons toinvestigate the genetic variability and response to selectionamong all the crosses. Top seven progenies which wereselected on the basis of high yield in F2 generation whichwere also good performers in F3 generation with high yieldand other desirable traits. The selected crosses were foundfree from doubles and bolters in F3 generation. This indicatesthe selection done from F2 to F3 generation is effective fordouble and bolter bulbs which certainly helps to increasethe marketable bulb yield. High degree of variation wasobserved for all the traits studied and the difference betweenphenotypic and genotypic coefficient of variation was foundto be narrow for most of the traits. More than 30% marketableyield enhancement was observed in four progenies viz.,Couger × DOGR-595, Reforma × DOGR-595, Mercedes ×Bhima Super and Collina × DOGR-597 in comparison withbest check Bhima Shakti (41.17 t/ha) in F3 generationwhereas, more than 50 t/ha marketable yield was recorded infour progenies viz., Basic × RGO-53, Couger × DOGR-595,Mercedes × Bhima Super and Reforma × DOGR-595 in F3generation.

THE RELATIONSHIP BETWEEN THE APACHE II SCORE AND THE NUMBER OF DAYS OF HOSPITALIZATION IN THE INTENSIVE CARE UNIT (ICU) AT HARAPAN INSAN HOSPITAL, SENDAWAR WEST KUTAI

The APACHE II score is a method for determining disease severity and assessing patient mortality in ICU. The result of measuring the patient's condition was obtained in the first 24 hours of admission to the ICU. Scoring is used to estimate prognostic risk factors for patients who can leave the ICU room in recovering or dying conditions. The length of hospitalization for patients in the Intensive Care Unit (ICU) is on average more than 5 days. The purpose of this study was to determine the relationship between the APACHE II score and the range of days in the Intensive Care Unit (ICU) at RSUD Harapan Insan Sendawar West Kutai. The design of this study was cross-sectional. The sampling technique in this study used accidental sampling, and the research samplers were 30 respondents. The test instrument used the APACHE II Observation sheet. The results of the statistical analysis of the bivariate test using Chi-Square obtained a p-value of 0.757, which is greater than the alpha value, it means that there is no relationship between the APACHE II score and the range of days of hospitalization in the Intensive Care Unit (ICU) at Harapan Insan Hospital, Sendawar, West Kutai. The Odds Ratio (OR) value was obtained at 0.786, which means that patients who have an APACHE II score were in a low category, and they have an opportunity of 0.786 times to have a range of days of hospitalization in the category of short hospital days. There is no relationship between the APACHE II score and the range of days of hospitalization in the Intensive Care Unit (ICU) at Harapan Insan Hospital, Sendawar, West Kutai. The suggestions for hospital management to add beds in the ICU and the results of the research are expected to be guidelines for patient care in the ICU by using the APACHE II score and improving services in the ICU

Genome-Wide Identification, Phylogenetic and Expression Analysis of the B-Box Gene Family in the Woodland Strawberry (Fragaria vesca)

The strawberry (Fragaria × ananassa Duch.) is an important horticultural crop that is widely grown all over the world. Its sweetness, aroma, nutritional value and bright color make it popular. The woodland strawberry (Fragaria vesca) is a model plant for studying non-climacteric fruits because its respiration rate does not change significantly during fruit ripening. The B-box (BBX) protein family is made up of zinc-finger transcription factors important in plant growth and development. In this study, we identified 22 FveBBX genes from the newly released woodland strawberry genome database by comprehensive bioinformatics analysis. Phylogenetic analysis divided these FveBBX genes into five subfamilies. A promoter cis-acting element analysis detected 29 elements related to plant development, light response, abiotic stress and hormone response in the promoter of FveBBX genes. According to transcriptome data, relatively few BBX genes had tissue-specific expression, with examples including FveBBX12, which was expressed only in pre-fertilization cortex and pitch, and FveBBX19, which was specifically expressed in mature anthers. During fruit ripening, the expressions of eight FveBBX genes decreased by more than two-fold, and three FveBBX gene expressions increased more than two-fold both in “Ruegen” and “Yellow Wonder”. After cold and heat stresses, around half of the FveBBX genes displayed altered expression, especially FveBBX16 which showed an 8.3-fold increase in expression after heat treatment, while FveBBX14 showed at least an 11-fold decrease in expression after cold treatment. According to the result of quantitative real-time PCR (qRT-PCR), FveBBX genes’ expression differed depending on the photoperiod. Notably, FveBBX7 gene expression was the opposite during the first 16 h of the long-day (LD) and short-day (SD) conditions. This study provides helpful information for further research on BBX gene activity of the woodland strawberry in plant growth and development and adaptation to temperature and photoperiod environmental conditions.

Localized phosphorus application via P-dipping doubles applied P use efficiency and avoids weather-induced stresses for rice production on P-deficient lowlands

To achieve higher production with minimal environmental impact in sub-Saharan Africa (SSA), it is crucial to make technical transitions from low-input to nutrient-use-efficient production systems. P-dipping, a localized phosphorus (P) application on seedling roots, is a potential approach to enable such a transition for lowland rice production. However, empirical evidence on the effectiveness of this approach in smallholders’ heterogeneous field conditions is lacking. Therefore, 18 on-farm trials were implemented by applying three P application treatments (zero P; P broadcasting at 13.1 kg P ha−1; P-dipping at 13.1 kg P ha−1) with and without N top-dressing (60 kg N ha−1) under a range of topographic, edaphic, and climatic conditions in the highlands of Madagascar. The P-dipping had consistently greater yields vs. zero P, with an average increase of 1.1 ± 0.7 t ha−1 and 1.8 ± 0.7 t ha−1 under non-N-applied and N-applied conditions, respectively. These yield gains by P-dipping corresponded to substantially high agronomic P-use efficiency (AEP: kg yield gain per kg P applied) of 82 ± 52 kg kg−1 in the non-N-applied plots and 136 ± 51 kg kg−1 in the N-applied plots that were both twice as large as those obtained from P broadcasting. The effect was particularly prominent in fields at high elevation and late-transplanted fields at the low elevation site where P-dipping alleviated not only P deficiency but also late-season low-temperature stress by shortening days to heading. The P-dipping effect was also increased when the fields had erratic water levels after transplanting, which was associated with vigorous initial growth and avoidance of submergence stress. No significant correlations were detected between AEP values and any of the soil properties except for P availability. This study revealed that the effect of P-dipping is consistent in various P-deficient soils and is enhanced by combining with N topdressing and when fields are prone to late-season cold stress or early season submergence stress. The finding of this study provides a practical insight for smallholder rice farmers how and where P fertilizer is effectively applied toward sustainable intensification and resilience to weather-induced stress in SSA.

A Farmer’s Approach to Detecting Photoperiod Sensitivity in Rice (Oryza sativa ssp. indica) Landraces

Most indigenous rice landraces are sensitive to photoperiod during short day seasons, and this sensitivity is more pronounced in indica than in japonica landraces. Attempts to identify photoperiod sensitive (PPS) cultivars based on the life history stages of the rice plant, and several models and indices based on phenology and day length have not been precise, and in some cases yield counterfactual inferences. Following the empirical method of traditional Asian rice farmers, the author has developed a robust index, based on the sowing and flowering dates of a large number of landraces grown in different seasons from 2020 to 2023, to contradistinguish PPS from photoperiod insensitive cultivars. Unlike other indices and models of photoperiod sensitivity, the index does not require the presumed duration of different life history stages of the rice plant but relies only on the flowering dates and the number of days till flowering of a rice cultivar sown on different dates to consistently identify photoperiod sensitive cultivars.

Intrathecal 1% 2-chlorprocaine for short gynecological day care procedures: Prospective, randomized, dose finding study.

Establishing the optimum dose of intrathecal 1% 2-chlorprocaine may reduce the discharge time and encourage more widespread use of spinal anesthesia for day care procedures. The aim of this study was to compare the efficacy and recovery characteristics of three different doses of intrathecal 1% 2-chlorprocaine for short gynecological day care procedures. Fifty-one patients scheduled for elective day care gynecological procedures lasting less than 60 min and were randomly divided into three groups of 17 each to receive 35 mg, 40 mg, or 45 mg intrathecal 1% 2-chlorprocaine. Demographic data, time required to achieve readiness for surgery, time required to attain discharge criteria, maximum block height achieved, and adverse effects were recorded in each group. The time required to achieve readiness for surgery was similar between the three groups (P = 0.306). However, 35 mg group required the shortest time to ambulate and there was a significant difference as compared with both 40 mg (P = 0.012) and 45 mg (P = 0.001). Voiding and the fulfillment of the discharge parameters were also attained more rapidly in the 35 mg group [133 (120,155) min] as compared with both 40 mg [164 (145,175) min, P = 0.000] and 45 mg [160 (150,175) min, P = 0.000]. None of the patients reported neurological symptoms during the follow-up. The 35 mg intrathecal 1% 2-chlorprocaine not only provides reliable anesthesia for short gynecological procedures but also facilitates faster achievement of the discharge parameters as compared with the 40 mg and 45 mg doses.

Exogenous abscisic acid represses rice flowering via SAPK8-ABF1-Ehd1/Ehd2 pathway

IntroductionRice flowering is a major agronomic trait, determining yield and ecological adaptability in particular regions. ABA plays an essential role in rice flowering, but the underlying molecular mechanism remains largely elusive. ObjectivesIn this study, we demonstrated a “SAPK8-ABF1-Ehd1/Ehd2” pathway, through which exogenous ABA represses rice flowering in a photoperiod-independent manner. MethodsWe generated abf1 and sapk8 mutants using the CRISPR-Cas9 method. Using yeast two-hybrid, Pull down, BiFC and kinase assays, SAPK8 interacted and phosphorylated ABF1. ABF1 directly bound to the promoters of Ehd1 and Ehd2 using ChIP-qPCR, EMSA, and LUC transient transcriptional activity assay, and suppressed the transcription of these genes. ResultsUnder both long day and short day conditions, simultaneous knock-out of ABF1 and its homolog bZIP40 accelerated flowering, while SAPK8 and ABF1 over-expression lines exhibited delayed flowering and hypersensitivity to ABA-mediated flowering repression. After perceiving the ABA signal, SAPK8 physically binds to and phosphorylates ABF1 to enhance its binding to the promoters of master positive flowering regulators Ehd1 and Ehd2. Upon interacting with FIE2, ABF1 recruited PRC2 complex to deposit H3K27me3 suppressive histone modification on Ehd1 and Ehd2 to suppress these genes transcription, thereby leading to later flowering. ConclusionOur work highlighted the biological functions of SAPK8 and ABF1 in ABA signaling, flowering control and the involvement of a PRC2-mediated epigenetic repression mechanism in the transcription regulation governed by ABF1 on ABA-mediated rice flowering repression.

Genome-Wide Identification, Classification and Expression Analyses of MADS-Box Genes Reveal Their Role in Stem Gall Formation and Expansion of Zizania latifolia

MADS-box genes are important transcription factors in eukaryotes that are involved in regulating the growth and development of many plants. Jiaobai is a special aquatic vegetable formed through the stem expansion of Zizania latifolia infected by Ustilago esculenta and is wildly cultivated in Southeast Asia. To date, the biological function of MADS-box genes in Z. latifolia remains largely unknown. In this study, a genome-wide search for MADS-box genes in Z. latifolia was performed, and 87 MADS-box genes were identified. According to the phylogenetic analysis, there were 27 type I genes and 60 type II genes. The type I genes were mainly distributed in the Mα, Mβ and Mγ subfamilies, and the type II genes were divided into 14 subfamilies and unevenly distributed across 17 chromosomes. The encoded protein sequences ranged from 91 to 433 amino acids, the number of exons was 1~14, and most type I genes did not contain introns. The promoter region contained a large number of functional domains related to light response, plant hormones, stress and the meristem. An analysis of the expression patterns showed that there were massive differences in the expression of the MADS-box genes in different tissues, with six genes highly expressed in leaves and eight genes highly expressed in the stem apical meristem. Photoperiod and temperature were found to regulate the formation of the stem gall (SG) of Z. latifolia, and short-day (SD) conditions had an obvious promoting effect. ZlMADS57 and ZlMADS85 were significantly increased in SG under SD. Further analysis of the expression levels of MADS-box genes during the developmental stages of Z. latifolia found that the ZlMADS45, ZlMADS57, ZlMADS81 and ZlMADS85 were highly expressed 10 days before the SG formation, and ZlMADS66 reached its highest value on the day when the SG began forming. ZlMADS14, ZlMADS15, ZlMADS32, ZlMADS36, ZlMADS59 and ZlMADS71 were highly expressed after SG expansion, indicating that the MADS-box gene may play an important role in regulating SG formation and the subsequent expansion of Jiaobai. This study provides a reference for the functional identification of the MADS-box gene family and establishes a foundation for regulating the maturity of Z. latifolia.

Identification of BBX gene family and its function in the regulation of microtuber formation in yam

BBX proteins play important roles in all of the major light-regulated developmental processes. However, no systematic analysis of BBX gene family regarding the regulation of photoperiodic microtuber formation has been previously performed in yam. In this study, a systematic analysis on the BBX gene family was conducted in three yam species, with the results, indicating that this gene plays a role in regulating photoperiodic microtuber formation. These analyses included identification the BBX gene family in three yam species, their evolutionary relationships, conserved domains, motifs, gene structure, cis-acting elements, and expressional patterns. Based on these analyses, DoBBX2/DoCOL5 and DoBBX8/DoCOL8 showing the most opposite pattern of expression during microtuber formation were selected as candidate genes for further investigation. Gene expression analysis showed DoBBX2/DoCOL5 and DoBBX8/DoCOL8 were highest expressed in leaves and exhibited photoperiod responsive expression patterns. Besides, the overexpression of DoBBX2/DoCOL5 and DoBBX8/DoCOL8 in potato accelerated tuber formation under short-day (SD) conditions, whereas only the overexpression of DoBBX8/DoCOL8 enhanced the accelerating effect of dark conditions on tuber induction. Tuber number was increased in DoBBX8/DoCOL8 overexpressing plants under dark, as well as in DoBBX2/DoCOL5 overexpressing plants under SD. Overall, the data generated in this study may form the basis of future functional characterizations of BBX genes in yam, especially regarding their regulation of microtuber formation via the photoperiodic response pathway.

Diversity of Flower Opening Time and Duration in Rice (Oryza sativa ssp. indica) Landraces of South and Southeast Asia in Different Cultivation Seasons

Different cultivars of rice (Oryza sativa) open at different times of the day, and the overlap of anthesis time in rice between the neighbouring cultivars is of crucial importance to the degree of cross pollination in rice. Nevertheless, none of the past experiments with cross pollination between different rice cultivars ever reported the respective flower opening time (FOT) and flower exposure duration (FED) of the parent cultivars, until recently. The authors present here the first record of FOT and FED of 1114 indica rice landraces of South and Southeast Asia, growing during summer and winter seasons in three consecutive years. The authors also present an analysis of the influences of the growing season on the anthesis behaviour, and present the first records of the FOT and FED variability on sunny and cloudy days of a large number of landraces. The data show that rice florets tend to open earlier in the morning (that is, take a shorter time to anthesis after sunrise) on sunny days than on cloudy days, and also significantly later during long day seasons (spring and summer) than during short day season (winter); and that FED is inversely related to both FOT and the length of duration from sunrise to first flower opening. The wide ranges of FOT (8:50 a.m. to 12:40 p.m.) and FED (15 to 194 minutes) also suggest the ample time window for receiving pollen from neighbouring cultivars with different FOT, enhancing the chances of cross pollination between hundreds of rice landraces with FOT and FED overlaps.

Potential for urban warming to postpone overwintering dormancy of temperate mosquitoes

Cities are generally hotter than surrounding rural areas due to the Urban Heat Island (UHI) effect. These increases in temperature advance plant and animal phenology, development, and reproduction in the spring. However, research determining how increased temperatures affect the seasonal physiology of animals in the fall has been limited. The Northern house mosquito, Culex pipiens, is abundant in cities and transmits several pathogens including West Nile virus. Females of this species enter a state of developmental arrest, or reproductive diapause, in response to short days and low temperatures during autumn. Diapausing females halt reproduction and blood-feeding, and instead accumulate fat and seek sheltered overwintering sites. We found that exposure to increased temperatures in the lab that mimic the UHI effect induced ovarian development and blood-feeding, and that females exposed to these temperatures were as fecund as non-diapausing mosquitoes. We also found that females exposed to higher temperatures had lower survival rates in winter-like conditions, despite having accumulated equivalent lipid reserves relative to their diapausing congeners. These data suggest that urban warming may inhibit diapause initiation in the autumn, thereby extending the active biting season of temperate mosquitoes.

A novel MORN-motif type gene GmMRF2 controls flowering time and plant height of soybean

The flowering time of soybean is a highly important agronomic characteristic, which affects the adaptability and yield. AtMRF1, a MORN-repeat motif gene, acts as a floral promoter in Arabidopsis, its functions in soybean are not yet understood. Here, we employed qRT-PCR to analyze the tissue expression patten of MRF1 homologs in soybean and determined that the GmMRF2 gene, containing a MORN-motif, highly expressed in the shoot and responded to photoperiod. GmMRF2 overexpression soybean lines exhibited earlier flowering time under long-day (LD) conditions, and increased plant height under both LD and short-day (SD) conditions compared to wild-type (WT) plants. The expression levels of gibberellic acid (GA) pathway genes that positively regulate plant height genes and flowering-promoting genes were up-regulated in the GmMRF2 overexpression lines, were up-regulated in the GmMRF2 overexpression lines. Further study revealed that GmMRF2 interacted with GmTCP15 to co-induce the expression of GmSOC1b. Together, our results preliminarily reveal the functions and mechanisms of GmMRF2 in regulating flowering time and plant height, provide a new promising gene for soybean crop improvement.

Rice florigens control a common set of genes at the shoot apical meristem including the F-BOX BROADER TILLER ANGLE 1 that regulates tiller angle and spikelet development.

Rice flowering is triggered by transcriptional reprogramming at the shoot apical meristem (SAM) mediated by florigenic proteins produced in leaves in response to changes in photoperiod. Florigens are more rapidly expressed under short days (SDs) compared to long days (LDs) and include the HEADING DATE 3a (Hd3a) and RICE FLOWERING LOCUS T1 (RFT1) phosphatidylethanolamine binding proteins. Hd3a and RFT1 are largely redundant at converting the SAM into an inflorescence, but whether they activate the same target genes and convey all photoperiodic information that modifies gene expression at the SAM is currently unclear. We uncoupled the contribution of Hd3a and RFT1 to transcriptome reprogramming at the SAM by RNA sequencing of dexamethasone-inducible over-expressors of single florigens and wild-type plants exposed to photoperiodic induction. Fifteen highly differentially expressed genes common to Hd3a, RFT1, and SDs were retrieved, 10 of which still uncharacterized. Detailed functional studies on some candidates revealed a role for LOC_Os04g13150 in determining tiller angle and spikelet development and the gene was renamed BROADER TILLER ANGLE 1 (BRT1). We identified a core set of genes controlled by florigen-mediated photoperiodic induction and defined the function of a novel florigen target controlling tiller angle and spikelet development.

Spectrum of low-intensity screw-in horticultural light-emitting diode lamps influences time to flower and finished quality of long-day ornamental species

Bedding plants with a long-day (LD) flowering requirement constitute a substantial portion of annuals and perennials produced in the United States for spring sales. However, greenhouse production often occurs when the day length is naturally short and not conducive for flower induction of LD plants (LDPs). Thus, growers must create artificial LDs through day-extension, cyclic, or night-interruption (NI) lighting to promote flowering of LDPs. Many low-intensity, screw-in horticultural light-emitting diode (LED) lamps are now commercially available, though their emission spectra vary. Therefore, the objective of our study was to quantify the influence of various commercially available low-intensity screw-in horticultural LED lamps on the flowering and growth responses of LDPs. We grew several obligate and facultative LD annuals under either a 9-h truncated short-day (SD), or a 9-h SD with NI lighting from 2200 to 0200 hr each day. NI treatments consisted of Feit 9-W Non-Dimmable Plant Grow Lights (Feit), General Electric (GE) 10-W Arize™ Greenhouse Pro-Photoperiodic LED Lamps (GE), Philips 13-W GreenPower LED flowering lamp 2.0 s (Philips), or TotalGrow ™ 16-W Pure Flowering 200 Lamps (TotalGrow). Philips and GE lamps hastened flowering of all LDPs studied, while TotalGrow lamps promoted or hastened flowering on a genus-specific basis. Flowering was delayed by up to 11 d under Feit lamps and plants developed more nodes and inflorescences at open flower than the other lighting treatments. Generally, the height of plants within genera were similar regardless of the lighting treatment. However, plants grown under TotalGrow lamps had a larger stem length than those grown under the other lighting treatments as they emitted the highest percentage of FR light. Therefore, greenhouse growers should not base their decision solely on the price of lamps.

Towards environmentally sustainable growing media for strawberry cultivation: Effect of biochar and fertigation on circular use of nutrients

In controlled environment horticulture, nutrients are retained in horticultural substrates, resulting in additional export of the nutrients provided through fertigation. To increase feasibility of the circular use of renewable growing media, nutrient retention in the substrate should remain low during cultivation. The aim of the present study was to examine the effect on nutrient retention (1) if nutrient input via fertigation is reduced and (2) if alternative growing media are used. Nutrient dynamics were studied for soilless strawberry cultivation in two full-scale greenhouse trials with the short day cultivar Elsanta and with a new substrate blend with 25% v/v wood fiber and 15% v/v green compost versus a conventional peat-based blend (75/15/10% v/v peat/coir/perlite). The conventional fertigation regime was compared with a reduced fertigation regime, which contained 65% of the standard concentration for N, P K, Mg, Ca and S. The first trial was a nine month autumn-spring cycle; the second trial was a two month autumn cultivation. Peat-reduced blends with or without wood-based biochar resulted in the same fruit yield as the peat-based blends. Trial length and fertigation regime interacted to affect yield, with significantly lower yield in the long trial under reduced fertigation versus conventional fertigation, and higher yield under reduced fertigation in the shorter trial. These findings indicate that nutrient concentrations in the applied fertigation should not be reduced during the long autumn-spring cycle. Ca (76–88%), Mg (70–85%) and N (61–81%) are mainly retained in the spent medium, while K is mainly retained in the aboveground biomass (> 60%). K contents in the peat-reduced substrate clearly decreased during cultivation, the peat-reduced blend may thus be a source of K. Wood-based biochar in the blend (3–10% v/v) showed no effect on either nutrient retention or nutrient balance.

Adaptation to high latitudes through a novel allele of Hd3a strongly promoting heading date in rice.

A novel Hd3a allele strongly promoting rice heading date was identified, and it functions through florigen activation complex (FAC) and was selected during the spread of rice cultivation to high-latitude areas. Heading date is a critical agronomic trait for rice that determines the utilization of light and temperature conditions and thereby affects grain yield. Rice is a short day (SD) plant, and its photoperiodic information is processed by complex pathways and integrated by florigens to control flowering. In this study, we identified a novel allele for the florigen gene Heading date 3a (Hd3a), characterized by a C435G substitution in its coding region, by a genome-wide association study (GWAS) approach in a panel of 199 high-latitude japonica rice varieties. The C435G substitution induces plants to flower 10days earlier in high-latitude area (long day condition). Then, we mutated C435 to G in Hd3a by prime editing and found the point mutation plants flowered 12days earlier. Further molecular experiments showed the novel Hd3a protein can interact with GF14b protein and increase the expression of OsMADS14, the output gene of florigen activation complex (FAC). Molecular signatures of selection indicated that the novel Hd3a allele was selected during the process of rice cultivation expansion into high-latitude areas. Collectively, these results provide new insights into heading date regulation in high-latitude areas and advance improvements to rice adaptability to enhance crop yield.

Morpho-horticultural potential of seven strawberry cultivars for two consecutive cycles

Maintaining plants for two consecutive cycles in strawberry cultivation makes it possible to reduce costs with the acquisition of daughter plants and allows fruit production throughout the year. Thus, the objective of this study was to investigate whether strawberry cultivars grown for two consecutive cycles in a greenhouse change their horticultural potential. The research was carried out in the municipality of Passo Fundo, State of Rio Grande do Sul, Brazil. We tested seven strawberry cultivars (classified as short days and neutral days in terms of flowering) in two production cycles. The cultivars morphology was characterized, and the fruit production and quality were evaluated. The morphological descriptor that most contributed to the divergence among cultivars corresponded to anthocyanin coloration of stipules. ‘Aromas’ stood out for the greater amount of fruit produced in both production cycles. In the first cycle ‘Albion’, ‘Camino Real’, and ‘Monterey’ produced fruits with the highest average fresh masses. Phenolic compounds of the fruits were superior in the second cycle of cultivation in relation to the first cycle. The total flavonoid content was higher in ‘Aromas’, ‘Camarosa’, ‘Camino Real’, and ‘Monterey’. ‘Camarosa’ and ‘San Andreas’ had the highest concentration of total polyphenols. The total antioxidant capacity was higher in ‘Aromas’ and ‘Camarosa’. It is concluded that strawberry cultivars conducted for two consecutive cycles in a greenhouse show variations in their horticultural potential. Producers who want to stagger their crops should choose ‘Aromas’ to obtain greater productive potential (in both cycles) and ‘Camarosa’ to meet the demanding consumer market in fruit quality.

Shift in the Light Quality of Night Interruption Affects Flowering and Morphogenesis of Petunia hybrida.

Petunia hybrida Hort. "Easy Wave Pink", a qualitative long-day plant (LDP), was investigated to study the effects of the night interruption light (NIL) provided by light-emitting diodes (LEDs) quality shifting on the morphogenesis, blooming, and transcription of photoreceptor genes. Plants were grown in a closed-type plant factory employing white (W) LEDs at an intensity of 180 μmol·m-2·s-1 PPFD provided for short day (SD, 10 h light, 14 h dark), long day (LD, 16 h light, 8 h dark), or SD with 4 h night interruption (NI) with LEDs at an intensity of 10 μmol·m-2·s-1 PPFD. The NIL quality was shifted from one light spectrum to another after the first 2 h of NI. Light treatments consisting of all possible pairings of W, far-red (Fr), red (R), and blue (B) light were tested. The SD and LD were referenced as the control, while 12 NI treatments involved altering LED NIL qualities, as follows: from R to B (NI-RB), from B to R (NI-BR), from Fr to R (NI-FrR), from R to Fr (NI-RFr), from Fr to B (NI-FrB), from B to Fr (NI-BFr), from B to W (NI-BW), from W to B (NI-WB), from W to Fr (NI-WFr), from Fr to W (NI-FrW), from W to R (NI-WR), and from R to W (NI-RW). The NI-RFr resulted in the longest shoots, while the NI-WR and NI-RW resulted in the shortest shoots. NI-WR, NI-RW, NI-BW, NI-WB, NI-RFr, NI-RB, NI-BR, and LD all exhibited flowering. High-level expressions of photoreceptor genes were confirmed in the NI-RFr, NI-FrR, NI-BFr, NI-RW, and NI-WR treatments. Morphogenesis and blooming were both impacted by the photoperiod. The first NIL had no effects on the flowering or the morphogenesis, but the second NIL had a profound impact on both.

Impact of warm spells during late fall and winter on frost hardiness of short-day treated Norway spruce seedlings

Warm spells during the late fall and winter are expected to become more frequent in boreal areas due to climate change. The aims of our study were to investigate whether warm spells in the late fall and winter cause deacclimation of Norway spruce (Picea abies (L.) Karst.) seedlings, whether the seedlings are capable of reacclimating in response to a subsequent cold period, and whether a short-day (SD) treatment applied in a nursery affects seedlings’ responses to warm and cold spells during the non-growing season (hereafter off-season). During the preceding growing season, the seedlings were treated either with a SD treatment (SD1: June 29 – July 20 or SD2: July 20 – August 10) or were grown in a natural photoperiod. The seedlings were artificially exposed to a 7-day warm spell, followed by a 7-day cold spell on four occasions (late fall: October and November; winter: January and March). The frost hardiness of the needles and the probability of bud damage were determined before and after the warm spell and after the cold spell. The dormancy status of the seedlings was also determined. Warm spells reduced the frost hardiness in needles and increased the probability of bud damage in January and March, but not in October and November. Needles were able to reacclimate from November to January, and buds also in early March. Our results indicate that in boreal areas, warm spells followed by low temperatures may predispose Norway spruce seedlings to freezing damage later in the winter, but not in the late fall. The seedlings that received SD2 treatment retained an ability to reacclimate after a warm spell in March, unlike the seedlings in the other photoperiod treatments, indicating that the responses of seedlings to the fluctuating temperature conditions in winter are affected by the growth conditions during the previous growing season. Therefore, the use and timing of SD treatment may affect survival of fall-planted seedlings and seedlings that overwinter outdoors in nurseries, especially during snowless winters.

GmGAMYB-BINDING PROTEIN 1 promotes small auxin-up RNA gene transcription to modulate soybean maturity and height.

Flowering time, maturity, and plant height are crucial agronomic traits controlled by photoperiod that affect soybean (Glycine max [L.] Merr.) yield and regional adaptability. It is important to cultivate soybean cultivars of earlier maturity that adapt to high latitudes. GAMYB-binding protein 1 (GmGBP1), a member of the SNW/SKIP family of transcriptional coregulators in soybean, is induced by short days and interacts with transcription factor GAMYB (GmGAMYB) during photoperiod control of flowering time and maturity. In the present study, GmGBP1:GmGBP1 soybean showed the phenotypes of earlier maturity and higher plant height. Chromatin immunoprecipitation sequencing (ChIP-seq) assays of GmGBP1-binding sites and RNA sequencing (RNA-seq) of differentially expressed transcripts in GmGBP1:GmGBP1 further identified potential targets of GmGBP1, including small auxin-up RNA (GmSAUR). GmSAUR:GmSAUR soybean also showed earlier maturity and higher plant height. GmGBP1 interacted with GmGAMYB, bound to the promoter of GmSAUR and promoted the expression of FLOWER LOCUS T homologs 2a (GmFT2a) and FLOWERING LOCUS D LIKE 19 (GmFDL19). Flowering repressors such as GmFT4 were negatively regulated, resulting in earlier flowering and maturity. Furthermore, the interaction of GmGBP1 with GmGAMYB increased the gibberellin (GA) signal to promote height and hypocotyl elongation by activating GmSAUR and GmSAUR bound to the promoter of the GA-positive activating regulator gibberellic acid-stimulated Arabidopsis 32 (GmGASA32). These results suggested a photoperiod regulatory pathway in which the interaction of GmGBP1 with GmGAMYB directly activated GmSAUR to promote earlier maturity and plant height in soybean.