Short Days Research Articles

Patient Experiences of Brachytherapy for Locally Advanced Cervical Cancer: Hearing the Patient Voice Through Qualitative Interviews

BackgroundBrachytherapy for gynaecological cancer is reported to cause pain, anxiety and distress with no clear guidance for optimising patient experiences. The aim of this study was to explore patient experiences of brachytherapy and views on improvements. Materials and MethodsSemi-structured interviews were undertaken with patients who had received brachytherapy for locally advanced cervical cancer. Two cohorts were recruited: cohort one had recently had brachytherapy, cohort two were a year post brachytherapy. Four recruitment sites were selected, where brachytherapy is given in different ways, some with short day case procedures and others having one or two overnight stays with applicators in place. Consecutive patients were invited to interview. Participants were asked to retell their brachytherapy story, with views on their care and ideas for improvement. Interviews were audio-recorded, transcribed and data analysed following Braun and Clarke's method for reflexive thematic analysis.16 ResultsThirty five interviews were conducted (20 in cohort one and 15 in cohort two). Participant's ages ranged from 28 to 87 years. The interview duration ranged from 22 to 78 minutes. Difficult and traumatic experiences were reported, including periods of severe pain and perceptions of poor care. However, some participants described positive experiences and what went well.Three themes were developed: 1) How I got through it 2) Unpleasantness, discomfort and the aftermath 3) Emotional consequences and traumaSome aspects of medium and long duration brachytherapy were found to be more problematic compared with short duration brachytherapy. Exploring experiences at one year post brachytherapy has provided insights into the long-lasting impact of brachytherapy experiences. ConclusionHearing the patient voice has demonstrated that further work is needed to improve patient care in modern brachytherapy techniques using different regimes and durations, to minimise difficult and traumatic patient experiences. Study insights will inform future work to develop clinical care recommendations.

Hypothalamic-pituitary-gonadal axis response to photoperiod changes in female guanacos (Lama guanicoe)

The guanaco, a wild South American camelid, is renowned for its remarkable resilience to extreme conditions. Despite this, little is known about how reproductive hormones in female camelids are influenced during their seasonal breeding period, which occurs during long photoperiod. To explore this, the study investigated the response of the hypothalamic-pituitary–gonadal axis in female guanacos during short days (10L:14D; July) and long days (16L:8D; December) in the Mediterranean ecosystem (33°38′28″S, 70°34′27″W). Blood samples from 14 adult animals were collected, and measurements of melatonin, 17β-estradiol, FSH, and LH concentrations were taken. The results showed that melatonin concentration was lower (P < 0.05) during long days than short days, whereas 17β-estradiol, FSH, and LH concentrations were higher (P < 0.05) during long days compared to short days. Furthermore, the study detected the expression of the melatonin receptor 1A and kisspeptin in the hypothalamus and pituitary, suggesting that the pineal gland of female guanacos is sensitive to seasonal changes in day length. These findings also indicate a seasonal variation in the concentration of reproductive hormones, likely linked to the distinct modulation of the hypothalamic-pituitary-gonadal axis of female guanacos during short and long days.

Effect of Short Day and Low Temperature at the Nursery Stage on the Inflorescence and Yield of Six Different Strawberry (Fragaria ananassa Dutch.) Cultivars in a Soilless Culture System

In Korea, the majority of strawberry cultivation follows a forcing culture, where planting occurs in mid-September after the flower differentiation, and harvesting begins at the end of November. October and November constitute off-season, resulting in higher prices. The accelerated forcing culture involves artificially promoting flower differentiation to expedite strawberry harvest. This study aimed to identify the most suitable schedule for strawberry cultivation using the short-day and low-temperature treatments through greenhouse environmental control during the nursery stage. The selection of the most suitable cultivars for accelerated forcing culture among Korean breeding cultivars (‘Sulhyang’, ‘Kuemsil’, ‘Kingsberry’, ‘Vitaberry’, ‘Jukhyang’, and ‘Altaking’) was also part of the objectives. The nursery treatments were initiated on 4 July, 14 July, and 25 July. After approximately 5 weeks of treatment, transplanting was carried out. The control group was transplanted on 15 September. When night-chilling nursery treatment was applied on 4 July, followed by transplanting on 11 August, all six cultivars exhibited flowering earlier compared to the control group, leading to increased early yield. Particularly, the ‘Sulhyang’ cultivar showed the highest marketable yield at 68.6 g per plant in October. This research contributes to identifying the nursery cultivation schedule for off-season strawberry production and selecting suitable cultivars, and is expected to contribute to increased farm income.

Reactions of Short, Intermediate and Long Day Onion Genotypes in Turkish National Onion Breeding Program to Fusarium Basal Rot Disease

Onion basal rot (Fusarium oxysporum f. sp. cepae) disease exerts serious threats on global onion (Allium cepa L.) production and trade. Present breeding programs mostly focus on development of cultivars resistant to onion basal rot disease. Characterization of breeding material in breeding gene pool is the first step of breeding. This study was conducted to determine the susceptibility of 4 onion cultivars, 30 long-day, 1 intermediate-day and 21 short-day onion genotypes to onion basal rot disease. Significant differences were seen in disease susceptibility of the genotypes (P&amp;lt;0.01 ) in both onion seedling and bulb tests. Onion seedling and bulb tests revealed that resistance was not detected in short and intermediate-day onion genotypes and cultivars, while two of long-day onion genotypes (ACLD 7 and 8) were found to be tolerant. Based on present finding, 3 cultivars, 28 long-day, 1 intermediate-day and 21 short-day genotypes were identified as sensitive. ACLD 7 and 8 long-day onion genotypes, which were identified as promising in seedling tests, were also identified as tolerant in bulb tests and such findings proved the compliance of seedling and bulb tests. Bulbs were obtained from the long-day onion lines (ACLD 7-8 genotypes) that were found to be promising and survived in seedling tests and seeds were obtained from these genotypes to ensure progress of generation and they were included in breeding gene pool.

SPL16 and SPL23 mediate photoperiodic control of seasonal growth in Populus trees.

Perennial trees in boreal and temperate regions undergo growth cessation and bud set under short photoperiods, which are regulated by phytochrome B (phyB) photoreceptors and PHYTOCHROME INTERACTING FACTOR 8 (PIF8) proteins. However, the direct signaling components downstream of the phyB-PIF8 module remain unclear. We found that short photoperiods suppressed the expression of miR156, while upregulated the expression of miR156-targeted SQUAMOSA-PROMOTER BINDING PROTEIN-LIKE 16 (SPL16) and SPL23 in leaves and shoot apices of Populus trees. Accordingly, either overexpression of MIR156a/c or mutagenesis of SPL16/23 resulted in the attenuation of growth cessation and bud set under short days (SD), whereas overexpression of SPL16 and SPL23 conferred early growth cessation. We further showed that SPL16 and SPL23 directly suppressed FLOWERING LOCUS T2 (FT2) expression while promoted BRANCHED1 (BRC1.1 and BRC1.2) expression. Moreover, we revealed that PIF8.1/8.2, positive regulators of growth cessation, directly bound to promoters of MIR156a and MIR156c and inhibited their expression to modulate downstream pathways. Our results reveal a connection between the phyB-PIF8 module-mediated photoperiod perception and the miR156-SPL16/23-FT2/BRC1 regulatory cascades in SD-induced growth cessation. Our study provides insights into the rewiring of a conserved miR156-SPL module in the regulation of seasonal growth in Populus trees.

SpeedFlower: a comprehensive speed breeding protocol for indica and japonica rice.

To increase rice yields and feed billions of people, it is essential to enhance genetic gains. However, the development of new varieties is hindered by longer generation times and seasonal constraints. To address these limitations, a speed breeding facility has been established and a robust speed breeding protocol, SpeedFlower is developed that allows growing 4-5 generations of indica and/or japonica rice in a year. Our findings reveal that a high red-to-blue (2R > 1B) spectrum ratio, followed by green, yellow and far-red (FR) light, along with a 24-h long day (LD) photoperiod for the initial 15 days of the vegetative phase, facilitated early flowering. This is further enhanced by 10-h short day (SD) photoperiod in the later stage and day and night temperatures of 32/30 °C, along with 65% humidity facilitated early flowering ranging from 52 to 60 days at high light intensity (800 μmol m-2 s-1). Additionally, the use of prematurely harvested seeds and gibberellic acid treatment reduced the maturity duration by 50%. Further, SpeedFlower was validated on a diverse subset of 198 rice accessions from 3K RGP panel encompassing all 12 distinct groups of Oryza sativa L. classes. Our results confirmed that using SpeedFlower one generation can be achieved within 58-71 days resulting in 5.1-6.3 generations per year across the 12 sub-groups. This breakthrough enables us to enhance genetic gain, which could feed half of the world's population dependent on rice.

Genomic insight into variations associated with flowering-time and early-maturity in pigeonpea mutant TAT-10 and its wild type parent T21

Pigeonpea [Cajanus cajan (L.) Millspaugh] is an important grain legume crop with a broad range of 90 to 300 days for maturity. To identify the genomic variations associated with the early maturity, we conducted whole-genome resequencing of an early-maturing pigeonpea mutant TAT-10 and its wild type parent T21. A total of 135.67 and 146.34 million sequencing reads were generated for T21 and TAT-10, respectively. From this resequencing data, 1,397,178 and 1,419,904 SNPs, 276,741 and 292,347 InDels, and 87,583 and 92,903 SVs were identified in T21 and TAT-10, respectively. We identified 203 genes in the pigeonpea genome that are homologs of flowering-related genes in Arabidopsis and found 791 genomic variations unique to TAT-10 linked to 94 flowering-related genes. We identified three candidate genes for early maturity in TAT-10; Suppressor of FRI 4 (SUF4), Early Flowering In Short Days (EFS), and Probable Lysine-Specific Demethylase ELF6. The variations in ELF6 were predicted to be possibly damaging and the expression profiles of EFS and ELF6 also supported their probable role during early flowering in TAT-10. The present study has generated information on genomic variations associated with candidate genes for early maturity, which can be further studied and exploited for developing the early-maturing pigeonpea cultivars.

Modification of agricultural traits in cultivated varieties of barley and wheat

CRISPR/Cas technology makes it possible to induce mutations at defined positions. In breeding-oriented research, this opens up exciting opportunities for the targeted improvement of many agricultural crops. Wheat and barley are among the most important cereals in the world. However, the transformation poses a particular challenge for cereals and is strongly genotype dependent. This is because agrobacteria, which is mostly used for delivering the CRISPR/Cas system, have a limited compatibility with these non-host plants. Transformation of wheat is additionally difficult due to the large genome size and polyploidy.&#x0D; Besides obtaining improved genotypes, the object of the current study was to optimize the method of genomic editing based on the CRISPR/Cas system using particle bombardment for non-model varieties of barley and wheat. In barley, we targeted theNudgene that controls hulled/naked phenotype of the grain. Since the regeneration rate remains an issue for the cultivated cultivars, we used the JD633 vector that carries theGRF4-GIF1chimera to increase the efficiency of regeneration. We obtained five T0plants, carrying mutations. In wheat, targetingPpd-1genes that control photoperiod-dependent floral induction results in Cas9-induced mutations in 52 of 210 T0plants. The developed collection of wheat plants with different new alleles ofPpd-D1andPpd-B1genes is being studied for the expression under short day conditions and the effect on the vegetation period.&#x0D; Thus, we have obtained plants of the cultivated varieties of barley and wheat with edited agronomically important genes, using the improved protocols of biolistic transformation.&#x0D; This work was done within the framework of State Assignment Kurchatov Genomic Center of ICG SB RAS (No. 075-15-2019-1662).

Maintenance of permanent sexual activity throughout the year in seasonal bucks using short photoperiodic cycles in open barns

Seasonality of reproductive activity in rams and bucks is the major constraint in temperate and subtropical zones. Rapid alternation between 1 month of short days and 1 month of long days (LD) over three years in lightproof buildings eliminates this seasonality. We examined if this would also work in open barns, using only supplementary light. Over two years, one group of bucks (n = 7) was subjected to alternate 1 month of LD and 1 month of permanent light (LD–LL) and another group (n = 7) to alternate 1 month of LD and 1 month of natural light (LD–NL). A simultaneous control group, used for both experiments (CG1, n = 6; CG2, n = 6), remained under natural photoperiod. BW, testis weight (TW), plasma testosterone (T) and cortisol (C) were evaluated in all bucks. CG1 and CG2 bucks showed identical dramatic seasonal variations in BW (stable or decreasing in summer), TW (from 85 ± 12 g in February to 127 ± 7 g in July) and T (from 2.7 ± 1.2 ng/mL in January–April to 24.3 ± 3.2 ng/mL in June–October). By contrast, BW of LD–LL and LD–NL bucks increased regularly during the experiment. From 5 and 9 months after the experiment onset, LD–LL and LD–NL bucks, respectively, maintained constant TW of 115 ± 5 g until the experiment end. After the first 3 months <5 ng/mL, T of LD–LL bucks remained constant (5–10 ng/mL) until the experiment end. By contrast, T of LD–NL bucks showed four periods of low (<5 ng/mL) and two periods of high concentrations (18.1 ± 2.6 and 11.9 ± 3.4 ng/mL). Plasma C remained low (5–8 ng/mL) and did not change with group or light treatment. These results show for the first time in any seasonal photoperiodic species that it is possible to maintain the sexual activity of males all year round in open buildings using alternating periods of LD and LL. By contrast, return to NL instead of LL every other month does not prevent seasonality in T concentration. These results raise interesting questions about the photoperiodic control of neuroendocrine regulation of seasonal sexual activity and suggest that these treatments can be used to manage males in open barns in farms and in artificial insemination centres. (Spanish and French versions of the full text are available as Supplementary Materials S1 and S2).

Some features of the bioecology of the apple moth &lt;i&gt;Cydia pomonella&lt;/i&gt; L. in the conditions of the Moscow region

Relevance. Cydia pomonella L. (Lepidoptera: Tortricidae) is a dominant pest that annually causes significant damage to apple crops. Without a detailed study of the bioecological features of the development of the phytophage in specific study areas, which have undergone noticeable changes under the influence of global warming, it is impossible to build an effective protection system and ensure their environmental safety.Methods. The object of research is C. pomonella. When studying the age gradation and timing of the presence of caterpillars in fallen fruits, conventional and original methods were used; the width of the caterpillar head capsule was measured under an MBS-10 stereoscopic microscope using eyepieces with microscopic rulers. The study of the influence of the photoperiod on the behavior of C. pomonella under short day conditions was carried out in the laboratory in special containers, under natural light and at room temperature (about 21 °C).Results. Studies have shown that not all C. pomonella caterpillars leave fallen fruits within a maximum of one day. After three days of selection and analysis of fallen damaged fruits, caterpillars were found in 34.6–35.5% of them: 18.3–28.3% – age V, 18.3–30.2% – age IV, 28.3–47.9% – III age, 13.2–14.1% – II age, 1.4% – I age. In the laboratory, under short day conditions, according to the years of research, during October – November, 20–21.4% of butterflies flew out of the number of caterpillars of the last age that did not have time to form cocoons in the field.

Selection of sesame mutants for higher yield and yield contributing traits through gamma ray irradiation

The experiment was conducted to observe their performance regarding seed yield and yield attributes, and to select promising mutant(s) having higher seed yield with shorter maturity periods. Five mutants along with the mother variety and one check variety were evaluated following a randomized complete block design with three replications at three sesame growing areas of Bangladesh during Kharif-I, 2017. Analysis of variance showed highly significant variations among the mutants and checks for most of the characters in individual locations and combined over locations. The mutant SM-07 produced the highest seed yield (1522 kg ha-1) at each location with taller plants and the shortest maturity period. The heatmap and correlation matrix showed a significant positive correlation among the no. of branch plant-1, no. of pod plant-1, and the seed yield. Considering mean seed yield over locations, three mutants viz., SM-07, SM-06 and SM-04 produced higher seed yield (1522, 1483 ,and 1461 kg ha-1, respectively) with took short days (83-85 days) to maturity. These three mutants need to be further zonal evaluation for conformity of their performance. Bangladesh J. Nuclear Agric, 37(1): 91-100, 2023

BS O04 Can virtual reality exercise games improve compliance with preoperative prescriptive exercise programs in patients awaiting bariatric surgery?

Abstract Background Despite the recognised benefits of increased activity prior to any surgery, non-compliance rate with prescribed exercise regimens is perceived to be higher amongst patients with obesity. Virtual-reality is becoming more recognised as an adjunctive tool within the healthcare setting. In this setting the platform enables exercise games to be played and enjoyed in the comfort of the patient’s own home, either sitting or standing depending on physical disability. The study aims to identify whether VR exercise games could be considered part of the pre-operative exercise program in patients awaiting bariatric surgery and the effects of this technology on compliance. Methods A pilot study using block randomisation, patients with obesity planned for laparoscopic Roux-en-Y gastric bypass (LRYGB) or sleeve gastrectomy (LSG) between December 2020 and December 2023 were recruited to a 6-week pre-operative regular exercise (REG) programme of either regular walking activity (RWA) or exercise using Virtual Reality device (VRX). Patients who later decided not to follow the exercise protocol were included as control (NEG). Patients with epilepsy, uncontrolled arrhythmias, heart failure or those unable to use VR systems were excluded. Pre- and post-trial demographic and progress data and follow up survey using the New Zealand Physical Activity Questionnaire were collected. Results 43 patients were recruited, 46.4kg/m2 mean referral BMI (33.8 – 65.6, SD 6.4) and 84% female. Exercise non-compliance was comparable between RWA and VRX groups (40 vs 43% respectively). 56% of NEG had their operation during short day light season (44% of REG). NEG group reported higher rate of chronic pain, poor motivation, and higher incidents of changes to surgery date (33, 33 and 22% respectively vs. none in REG). While weight loss achieved in REG prior to the operation was higher than in NEG, there was no significant difference in weight loss between the groups at 3 months follow up. Conclusions While the role of prehabilitation exercise prior to major elective surgery is well documented, the search for the ideal approach to achieve this is still ongoing. This pilot study demonstrates the limitations certain chronic conditions in patients with obesity have on the success of a pre-operative exercise programme. While more data is needed, it is important to bear these limitations in mind when recruiting patients to any exercise programme. The compliance rate remains unfavourable despite the use of VR technology.

Effect of photoperiod on serum biochemistry, electrolytic balance, acute phase response and histopathology of butter catfish, Ompok bimaculatus (Bloch, 1794).

The present study was executed to evaluate the effect of photoperiod on serum biochemical parameters (glucose, cortisol, ALT, AST and LDH), electrolytic balance (Sodium and potassium), acute phase response (CRP) and histopathology (liver, kidney and skin) of an endangered high valued catfish, Ompok bimaculatus. Catfish (21.00 ± 1.53cm and 30.00 ± 2.31g) from the acclimatized stock were randomly distributed to six 120 × 45 × 60 cm3 FRP tanks (n = 20 fish per tank) and exposed to 1500lx light intensity under different photoperiods [24:0 light: dark (L: D), 15L: 9D, 12L: 12D, 9L: 15D, 0L: 24D and a natural photoperiod (control)], and fed at a daily rate of 2% of bodyweight, twice a day for 60days. Serum glucose, cortisol and enzymes including aspartate transaminase (AST), lactate dehydrogenase (LDH), alanine transaminase (ALT), and acute phase reactant, such as C-reactive protein (CRP) increased significantly (P < 0.05) in continuous light (24L: 0D), continuous dark (0L: 24D) and short day (9L: 15D) photoperiods, whereas in 15L: 9D and 12L:12D photoperiods, those were in decreasing trend. Serum electrolytes, i.e. potassium level was elevated and sodium level was declined in 24L: 0D, 0L: 24D and 9L: 15D photoperiod groups. Moreover, significant histological alterations in the liver, kidney and skin tissue were also evidenced in the experimented catfish. Typical polygonal hepatocytes with normal blood vessels in liver and normal organization of kidney were seen in catfish of 15L: 9D group. Histological analysis of other groups displayed nuclear degeneration, karyorrhexis, karyolysis, melanomacrophages, nuclear hypertrophy, sinusoid dilation and vacuolar degeneration in liver and hyaline droplets accumulation, granular degeneration, fragmentation of glomerulus and focal necrosis of epithelial cells in kidney. Additionally, general structure of the skin was observed in control group as well as in 15L: 9D group. Contrarily, in 24L: 0D group increased number of mucous cells and vacuoles was observed in the skin of butter catfish. In 9L: 15D and 0L: 24D photoperiods, O. bimaculatus exhibited ruptured epithelial cells, enlarged alarm cells, fat cells, necrotic cells and vacuoles in the skin tissue. The present study depicted that 15L: 9D photoperiod can induce better health of catfish, O. bimaculatus, which, in turn, can help farmers to increase the production of this high valued catfish in future.

Several short-day species can flower under blue-extended long days, but this response is not universal

Sole-source LED lighting enables spectral flexibility to achieve desirable plant characteristics and product quality. An earlier study from our lab showed that short-day plant chrysanthemum flowers normally under long days with dynamic lighting of 11 h dichromatic red-blue LED light extended with 4 h sole blue LED light. Such dynamic LED lighting is possible in vertical farms and opens the possibility to supply a higher daily light integral (DLI) to short-day plants by providing more hours of light and thus increase growth rate. This study aims to investigate for several short-day species whether normal flowering is obtained when 11 h of red-blue is extended with 4 h of sole blue LED light. Twelve genotypes of nine short-day plants species (kalanchoe - Kalanchoe blossfeldiana, perilla - Perilla frutescens, stevia - Stevia rebaudiana, artemisia - Artemisia annua, chrysanthemum - Chrysanthemum seticuspe and Chrysanthemum morifolium, cosmos - Cosmos bipinnatus, poinsettia - Poinsettia pulcherrima and wild tomato - Solanum habrochaites) were grown at three light conditions in a climate room: 11 h red-blue short day, 11 h red-blue extended with 4 h of sole blue, and 15 h red-blue long day. Mixed red and blue light (ratio 60:40) was provided at a total photosynthetic photon flux density (PPFD) of 100 µmol m−2 s−1 and sole blue light was provided at 40 µmol m−2 s−1 PPFD. Flowering response differed among species: kalanchoe, perilla and stevia flowered only in red-blue short day. Artemisia, chrysanthemum, cosmos, poinsettia, and wild tomato flowered in red-blue short day, and blue-extended long day but not in red-blue long day. However, there was a flowering delay in cosmos, poinsettia, and wild tomato under blue-extended long days compared to short days. In blue-extended long days plants received 15 % higher DLI resulting in a 4 to 36 % increase in total dry weight compared to short days. This study shows that increasing growth rate under light-limiting growth conditions through daylength-extension with sole blue light, without compromising flowering and quality, is possible for some, but not all short-day species.

Functional divergence of Arabidopsis REPRESSOR OF UV-B PHOTOMORPHOGENESIS 1 and 2 in repression of flowering.

Photoperiodic plants coordinate the timing of flowering with seasonal light cues, thereby optimizing their sexual reproductive success. The WD40-repeat protein REPRESSOR OF UV-B PHOTOMORPHOGENESIS 2 (RUP2) functions as a potent repressor of UV RESISTANCE LOCUS 8 (UVR8) photoreceptor-mediated UV-B induction of flowering under noninductive, short-day conditions in Arabidopsis (Arabidopsis thaliana); however, in contrast, the closely related RUP1 seems to play no major role. Here, analysis of chimeric ProRUP1:RUP2 and ProRUP2:RUP1 expression lines suggested that the distinct functions of RUP1 and RUP2 in repressing flowering are due to differences in both their coding and regulatory DNA sequences. Artificial altered expression using tissue-specific promoters indicated that RUP2 functions in repressing flowering when expressed in mesophyll and phloem companion cells, whereas RUP1 functions only when expressed in phloem companion cells. Endogenous RUP1 expression in vascular tissue was quantified as lower than that of RUP2, likely underlying the functional difference between RUP1 and RUP2 in repressing flowering. Taken together, our findings highlight the importance of phloem vasculature expression of RUP2 in repressing flowering under short days and identify a basis for the functional divergence of Arabidopsis RUP1 and RUP2 in regulating flowering time.

Early maturity 7 promotes early flowering by controlling the light input into the circadian clock in barley.

Breeding for variation in photoperiod response is crucial to adapt crop plants to various environments. Plants measure changes in day length by the circadian clock, an endogenous timekeeper that allows plants to anticipate changes in diurnal and seasonal light-dark cycles. Here, we describe the early maturity 7 (eam7) locus in barley (Hordeum vulgare), which interacts with PHOTOPERIOD 1 (Ppd-H1) to cause early flowering under non-inductive short days. We identify LIGHT-REGULATED WD 1 (LWD1) as a putative candidate to underlie the eam7 locus in barley as supported by genetic mapping and CRISPR-Cas9-generated lwd1 mutants. Mutations in eam7 cause a significant phase advance and a misregulation of core clock and clock output genes under diurnal conditions. Early flowering was linked to an upregulation of Ppd-H1 during the night and consequent induction of the florigen FLOWERING LOCUS T1 under short days. We propose that EAM7 controls photoperiodic flowering in barley by controlling the light input into the clock and diurnal expression patterns of the major photoperiod response gene Ppd-H1.

Phytochromes transmit photoperiod information via the evening complex in Brachypodium

BackgroundDaylength is a key seasonal cue for animals and plants. In cereals, photoperiodic responses are a major adaptive trait, and alleles of clock genes such as PHOTOPERIOD1 (PPD1) and EARLY FLOWERING3 (ELF3) have been selected for in adapting barley and wheat to northern latitudes. How monocot plants sense photoperiod and integrate this information into growth and development is not well understood.ResultsWe find that phytochrome C (PHYC) is essential for flowering in Brachypodium distachyon. Conversely, ELF3 acts as a floral repressor and elf3 mutants display a constitutive long day phenotype and transcriptome. We find that ELF3 and PHYC occur in a common complex. ELF3 associates with the promoters of a number of conserved regulators of flowering, including PPD1 and VRN1. Consistent with observations in barley, we are able to show that PPD1 overexpression accelerates flowering in short days and is necessary for rapid flowering in response to long days. PHYC is in the active Pfr state at the end of the day, but we observe it undergoes dark reversion over the course of the night.ConclusionsWe propose that PHYC acts as a molecular timer and communicates information on night-length to the circadian clock via ELF3.

INDETERMINATE1-mediated expression of FT family genes is required for proper timing of flowering in Brachypodium distachyon.

The transition to flowering is a major developmental switch in plants. In many temperate grasses, perception of indicators of seasonal change, such as changing day-length and temperature, leads to expression of FLOWERING LOCUS T1 (FT1) and FT-Like (FTL) genes that are essential for promoting the transition to flowering. However, little is known about the upstream regulators of FT1 and FTL genes in temperate grasses. Here, we characterize the monocot-specific gene INDETERMINATE1 (BdID1) in Brachypodium distachyon and demonstrate that BdID1 is a regulator of FT family genes. Mutations in ID1 impact the ability of the short-day (SD) vernalization, cold vernalization, and long-day (LD) photoperiod pathways to induce certain FTL genes. BdID1 is required for upregulation of FTL9 (FT-LIKE9) expression by the SD vernalization pathway, and overexpression of FTL9 in an id1 background can partially restore the delayed flowering phenotype of id1. We show that BdID1 binds in vitro to the promoter region of FTL genes suggesting that ID1 directly activates FTL expression. Transcriptome analysis shows that BdID1 is required for FT1, FT2, FTL12, and FTL13 expression under inductive LD photoperiods, indicating that BdID1 is a regulator of the FT gene family. Moreover, overexpression of FT1 in the id1 background results in rapid flowering similar to overexpressing FT1 in the wild type, demonstrating that BdID1 is upstream of FT family genes. Interestingly, ID1 negatively regulates a previously uncharacterized FTL gene, FTL4, and we show that FTL4 is a repressor of flowering. Thus, BdID1 is critical for proper timing of flowering in temperate grasses.

37 Precision Feeding of Prolific Sheep in Highly Productive Management Systems

Abstract Globally lamb production is constrained by seasonal reproduction and flock productivity. There is potential to reduce both with improved reproductive and nutritional management in systems with a reduced interbirth interval. These accelerated systems can improve productivity &amp;gt;2 times compared with conventional systems. Successful adoption of these systems has been hampered; however, by low and variable reproductive efficiency during the suboptimal breeding period (February to July). We designed a series of studies to address this problem using an 8-month birth interval system with Polled Dorset x Polypay ewes without the use of exogenous hormone or photoperiod therapies. In study 1, we examined prebreeding nutrition combined with the male effect on reproductive outcomes in both long (April/May) and short-day (Dec./Jan.) breeding seasons. Ewes were randomly allocated to one of 3 nutritional treatments after weaning during a 21-day prebreeding period: 50%, 100% or 200% of maintenance energy intake. Ewes were exposed to vasectomized rams the last 14 days of treatment followed immediately with fertile rams for a 34-day breeding period (22 to 27 ewes per vasectomized or fertile ram). Both litter size (1.60 short vs. 1.34 long) and conception (96% short vs. 86% long) were greater in the short season (P &amp;lt; 0.001). Nutrition did not impact conception in either season; however, litter size was increased 15% in long and 25% in short day breeding season in ewes fed 200% compared the other treatments. These results suggest that litter size can be improved in these systems regardless of season by elevating energy intake above current recommendations. In study 2, we examined the impact of energy status during 2 preconception periods: lactation (last 30 days of previous lactation) and flushing (21 days pre-breeding plus 34-day breeding period). During lactation ewes received either 70% (L), 100% (C), and 150% (H) of energy requirements according to litter size. During flushing, ewes received 70%, 100% and 160% of maintenance energy with reproductive management as for study 1. Blood samples collected every 3 to 4 days were analyzed for plasma progesterone concentration via radioimmunoassay. Season had a great impact on return to estrus with 18% of ewes exhibiting luteal phases before teaser ram introduction during long as compared with 99% during short-day season. Nutrition during lactation also impacted return to estrus but only in long days with 40% of ewes on the H diet exhibiting luteal phases compared with 14% on the L diet before teaser ram introduction. Collectively, this indicates that an increased rate on conception is possible without the use of exogenous hormones or photoperiod manipulation in accelerated systems. Furthermore, a high plane of preconception nutrition improves litter size regardless of season and may hasten return to estrus during the suboptimal breeding period.

Multiparametric MR Evaluation of the Photoperiodic Regulation of Hypothalamic Structures in Sheep

Most organisms on earth, humans included, have developed strategies to cope with environmental day-night and seasonal cycles to survive. For most of them, their physiological and behavioral functions, including the reproductive function, are synchronized with the annual changes of day length, to ensure winter survival and subsequent reproductive success in the following spring.Sheep are sensitive to photoperiod, which also regulates natural adult neurogenesis in their hypothalamus. We postulate that the ovine model represents a good alternative to study the functional and metabolic changes occurring in response to photoperiodic changes in hypothalamic structures of the brain.Here, the impact of the photoperiod on the neurovascular coupling and the metabolism of the hypothalamic structures was investigated at 3T using BOLD fMRI, perfusion-MRI and proton magnetic resonance spectroscopy (1H-MRS). A longitudinal study involving 8 ewes was conducted during long days (LD) and short days (SD) revealing significant BOLD, rCBV and metabolic changes in hypothalamic structures of the ewe brain between LD and SD. More specifically, the transition between LD and SD revealed negative BOLD responses to hypercapnia at the beginning of SD period followed by significant increases in BOLD, rCBV, Glx and tNAA concentrations towards the end of the SD period. These observations suggest longitudinal mechanisms promoting the proliferation and differentiation of neural stem cells within the hypothalamic niche of breeding ewes.We conclude that multiparametric MRI studies including 1H-MRS could be promising non-invasive translational techniques to investigate the existence of natural adult neurogenesis in-vivo in gyrencephalic brains.