Soybean(Glycine max) is a facultative short-day plant with a sensitive photoperiod perception and reaction system, which allows it to adjust its physiological state and gene regulatory networks to seasonal and diurnal...Soybean(Glycine max) is a facultative short-day plant with a sensitive photoperiod perception and reaction system, which allows it to adjust its physiological state and gene regulatory networks to seasonal and diurnal changes in environmental conditions. In the past few decades, soybean cultivation has spread from East Asia to areas throughout the world. Biologists and breeders must now confront the challenge of understanding the molecular mechanism of soybean photoperiodism and improving agronomic traits to enable this important crop to adapt to geographical and environmental changes. In this review, we summarize the genetic regulatory network underlying photoperiodic responses in soybean. Genomic and genetic studies have revealed that the circadian clock, in conjunction with the light perception pathways, regulates photoperiodic flowering. Here, we provide an annotated list of 844 candidate flowering genes in soybean, with their putative biological functions. Many photoperiod-related genes have been intensively selected during domestication and crop improvement. Finally, we describe recent progress in engineering photoperiod-responsive genes for improving agronomic traits to enhance geographic adaptation in soybean, as well as future prospects for research on soybean photoperiodic responses.展开更多
A later heading date generally leads to higher grain yield in favorable ecological regions;however,grain yield reaches a limit as the heading date exceeds a certain threshold.Ghd7 is the first cloned major gene that r...A later heading date generally leads to higher grain yield in favorable ecological regions;however,grain yield reaches a limit as the heading date exceeds a certain threshold.Ghd7 is the first cloned major gene that regulates heading date,plant height and grain number.Here,we investigated the relationship between Ghd7 and florigen genes Hd3a and RFT1,to determine their roles in regulating heading date and grain number under different photoperiods.Our results revealed that under long-day(LD)conditions,Hd3a acts prior to RFT1 to promote heading while negatively regulating plant height and grain number.In contrast,Ghd7 positively regulates heading date,plant height,and grain number by inhibiting both Hd3a and RFT1.Under short-day(SD)conditions,the functions of Hd3a and RFT1 remain consistent with those under LD conditions,but Ghd7 does not inhibit their expression,resulting in a weaker phenotypic effect compared to Hd3a.Additionally,under both LD and SD conditions,increased Ghd7 expression enhances its inhibitory effect on Hd3a and RFT1,leading to later heading and increased grain number;however,once the heading date exceeds 94 d,grain number no longer increases.Moreover,the gn1a allele increased grain number by 16.5%to 42.5%,while combinations of the elite alleles from Ghd7,Hd3a,RFT1,and Gn1a significantly increased grain number by up to 240.9%.Therefore,we propose a new breeding strategy to optimize the heading date and grain number using the Ghd7Hd3aRFT1gn1a combination of Ghd7,Hd3a,RFT1,and Gn1a under LD conditions,and the Ghd7hd3aRFT1gn1a combination under SD conditions.This strategy improved the yield of the high-quality Northeast variety Kongyu 131(KY131)by 69.1%in Beijing and 93.7%in Hainan.This strategy will greatly improve the efficiency of north-to-south adaptation in rice,providing theoretical guidance for expanding the geographical adaptability of rice varieties.展开更多
Climate warming is reshaping the phenology of plants in recent decades,with potential implications for forest productivity,carbon sequestration,and ecosystem functioning.While the effects of warming on secondary growt...Climate warming is reshaping the phenology of plants in recent decades,with potential implications for forest productivity,carbon sequestration,and ecosystem functioning.While the effects of warming on secondary growth phenology is becoming increasingly clear,the influenceof environmental factors on different developmental phases of xylem remains to be quantified.In this study,we investigated the temporal dynamics of xylem cell enlargement,wall-thickening,and the interval between these events in twelve temperate tree species from Northeast China over the period 2019–2024.We found that both cell enlargement and wall-thickening advanced significantlyin response to climate warming,with species-specific variations in the rate of advancement.Importantly,the advancing rate of wallthickening was greater than that of cell enlargement,leading to a shortening of the interval between these two events.Linear mixed-effects models revealed that photoperiod,forcing temperature,and precipitation were the primary environmental drivers influencingthe timing of both cell enlargement and wall-thickening,with photoperiod emerging as the most important factor.These results suggest that climate warming accelerates the heat accumulation required for the transition from xylem cell enlargement to wall-thickening,thereby shortening the time interval between these two developmental stages.Beyond contributing valuable multi-year xylem phenological data,our results provide mechanistic insights that enhance predictions of wood formation dynamics under future climate scenarios and improve the accuracy of forest carbon models.展开更多
Photoperiod and temperature are crucial factors that trigger flowering in Brassica juncea(B.juncea).However,the underlying regulatory mechanisms remain poorly understood.The MADS-box transcription factor AGL18 acts as...Photoperiod and temperature are crucial factors that trigger flowering in Brassica juncea(B.juncea).However,the underlying regulatory mechanisms remain poorly understood.The MADS-box transcription factor AGL18 acts as a pivotal repressor of floral transition and functions redundantly with AGL15.In this study,we isolated BjuAGL18-1 from B.juncea and identified two unique transcripts,resulting in two distinct proteins:a full-length protein,BjuAGL18-1L,and a truncated protein,BjuAGL18-1S.Further investigation showed that the two isoforms had similar subcellular localizations but different expression patterns in various plant tissues.Notably,BjuAGL18-1L and BjuAGL18-1S were abundantly induced under short-and long-day photoperiods,respectively.BjuAGL18-1L overexpression in B.juncea and Arabidopsis thaliana(A.thaliana)led to late flowering,whereas BjuAGL18-1S overexpression resulted in early flowering.Yeast two-hybrid,bimolecular fluorescent complementation,and luciferase complementation assays showed that BjuAGL18-1L,but not BjuAGL18-1S(which lacked the EAR motif),interacted with the co-repressor BjuAFR2 and the histone deacetylase BjuHDA9 to form a multiprotein complex.Further analysis indicated that BjuAGL18-1L could also form a complex with BjuAGL15 and bind to the BjuFUL promoter,thus inhibiting its expression.However,BjuAGL18-1S interacted with BjuAGL18-1L to form heterodimers,which attenuated their activities,likely by disrupting their binding to target genes,resulting in accelerated flowering progression.These results suggest that BjuAGL18-1 is involved in photoperiod-induced flowering via different regulatory mechanisms in B.juncea.展开更多
Mandarin fish(Siniperca scherzeri) has high market prices and significant market potential in China because of its highquality meat and high nutritional value. However, due to the limited scale of aquaculture, meeting...Mandarin fish(Siniperca scherzeri) has high market prices and significant market potential in China because of its highquality meat and high nutritional value. However, due to the limited scale of aquaculture, meeting the market demand is difficult, making the effective development of the aquaculture potential of mandarin fish an important challenge for the industry. In this study, a 30-d breeding experiment was conducted on mandarin fish larvae under three photoperiod conditions: G1 8 h light:16 h dark(8L:16D), G2 12 h light:12 h dark(12L:12D), and G3 16 h light:8 h dark(16L:8D). The results showed that the G2 group exhibited the best growth performance and development status, with final body weights, weight gain rates, and specific growth rates all higher than those of the other two groups(P < 0.05). Observations of sections from each group revealed that the intestinal villi length and muscle thickness of the G2 group were significantly greater than those of the other two groups(P < 0.05). The G2 group inhibited the transcriptional activation of key circadian rhythm genes, including nr1d2a, nr1d1 and per1, while upregulating the expression of BMAL1 in S. scherzeri.The activation of both the insulin signalling pathway and the Fox O signalling pathway enhanced the efficient secretion of insulin, which subsequently played a critical role in regulating fatty acid metabolism. This active fatty acid metabolism provided an optimal energy supply, ensuring that other nutrients were fully utilized during the growth and development process while minimizing unnecessary nutrient loss. Consequently, this mechanism effectively promoted the overall growth and development of S. scherzeri. This study was the first to elucidate the transcriptomic expression patterns of S. scherzeri under varying photoperiod conditions. In response to the cyclic alternation of day and night, S. scherzeri regulated their metabolic levels and the transcriptional activation of downstream target genes via insulin signalling.展开更多
Foxtail millet(Setaria italica)is an important crop and an emerging model plant.Photoperiodic flowering is a key determinant of its production and geographic expansion.In this study,we found that SiPRR37 is responsibl...Foxtail millet(Setaria italica)is an important crop and an emerging model plant.Photoperiodic flowering is a key determinant of its production and geographic expansion.In this study,we found that SiPRR37 is responsible for the major quantitative trait locus(QTL)Heading date 2(Hd2)identified in 680 foxtail millets using a genome-wide association study.Overexpression of SiPRR37 in foxtail millet significantly delayed the heading date under both natural long-day and short-day conditions.CRISPR/Cas9-induced Siprr37 mutants exhibited earlier flowering in long-day conditions but later flowering in short-day conditions.The critical day length(CDL)for the reversal of Siprr37’s function was around 14.3 h.Haplotype analysis revealed that accessions with the Tc1-Mariner transposon insertion in SiPRR37(Hap 1)flowered significantly earlier at higher latitudes,and later at lower latitudes,indicating that natural variants of SiPRR37 exert dual functions in flowering regulation according to geographic latitude.The gradual,successive decrease in the frequency of Hap 2 from low to high latitudes,with the concurrent increase of Hap 1,demonstrates that these haplotypes have undergone artificial selection.Further FST analysis demonstrated that SiPRR37 has contributed to the ecological adaption of foxtail millet.Additionally,we reveal that OsPRR37 promotes flowering in rice,while GmPRR37 may only inhibit flowering in soybean.Further diurnal expression and transgenic analyses suggest that the dual function of SiPRR37 might depend on SiHd1.Our study uncovered the distinct functional reversal of SiPRR37 and functional diversification of PRR37 homologs in SD crops.These findings not only enrich knowledge about the regulation of photoperiodic flowering,but also contribute to genetic improvement of crops’regional adaptability.展开更多
Understanding the phenology and productivity of Populus species is crucial for effective management and conservation strategies amid climate change.We investigated leaf budbreak timing,susceptibility to cold damage,le...Understanding the phenology and productivity of Populus species is crucial for effective management and conservation strategies amid climate change.We investigated leaf budbreak timing,susceptibility to cold damage,leaf dynamics,and biomass production of 168 Populus genotypes with diverse provenances in the southeastern United States.Our study revealed significant variation in budbreak timing across different taxa and years,with genotypes inheriting traits adapted to their parents’local climates.Temperature emerged as a key factor triggering budbreak,while leaf development depended on other environmental cues such as photoperiod.Notably,budbreak occurred approximately 20 days earlier in 2023 compared to 2022 due to higher accumulated degree days(ADDs).Short-rotation-coppice(SRC)management delayed budbreak by five to ten days.Cold damage was significant in 2023,particularly for genotypes from northern provenances and those with P.maximowiczii parentage.Severe damage was also observed in eastern cottonwood(Populus deltoides×Populus deltoides(D×D))genotypes,despite most having southeastern US parentages.Leaf dynamics,including leaf duration and leaf area index(LAI),varied across taxa and sites,with earlier budbreak correlating with extended growing seasons and increased LAI.Biomass production was intricately linked to phenological events,with earlier budbreak leading to increased biomass production and greater susceptibility to cold damage.Our findings highlight the importance of genetics,environment,and coppicing management in understanding and managing Populus phenology and biomass production.These insights provide valuable guidance for developing effective breeding,conservation,and management strategies for Populus species in the context of climate change.展开更多
The photoperiod/thermo-sensitive genic male sterility(P/TGMS)system is crucial for hybrid rice production,but challenges persist in seed purity(due to fertility conversion and mixed male seeds)and mechanization.Here,w...The photoperiod/thermo-sensitive genic male sterility(P/TGMS)system is crucial for hybrid rice production,but challenges persist in seed purity(due to fertility conversion and mixed male seeds)and mechanization.Here,we developed a novel hybrid seed production scheme using herbicide-resistance alleles(OsALS and CYP81A6).P/TGMS lines were bred for imazamox sensitivity and bentazon resistance,while male parents were engineered for the opposite traits.This system enables mechanical harvesting and ensures hybrid purity by eliminating self-pollinated contaminants through herbicide application.We identified suitable sterile lines and developed complementary male parents via breeding and CRISPR/Cas9 editing,validated through herbicide assays.This strategy enhances hybrid seed purity and mechanization efficiency in two-line hybrid rice production.展开更多
Gibberella stalk rot(GSR)caused by Fusarium graminearum is one of the most devastating diseases of maize,seriously impacting maize yield and quality,as well as the ability to use technology of mechanical harvesting.En...Gibberella stalk rot(GSR)caused by Fusarium graminearum is one of the most devastating diseases of maize,seriously impacting maize yield and quality,as well as the ability to use technology of mechanical harvesting.Environmental conditions including photoperiod affect crop disease resistance.However,the mechanism underlying photoperiod-regulated maize GSR resistance remains unexplored.We found in this study that GSR resistance is regulated by the ZmPIF4.1(Phytochrome-Interacting Factor4)-ZmPTI1c(Pto-Interacting 1)-ZmMYB31 module coupled with photoperiod.The functional analysis of zmpti1c mutant indicated that ZmPTI1c negatively regulates maize GSR resistance.Short day promoted the disease progression in both zmpti1c and wild-type plants.ZmPTI1c promoter contains multiple predicted cis-acting elements for light responses.Yeast one-hybrid assay(Y1H),Electrophoretic mobility shift analysis(EMSA),and Dual-luciferase(LUC)reporter assays demonstrated that ZmPIF4.1 binds to the G-box in ZmPTI1c promoter and activates its expression.Moreover,expression levels of ZmPIF4 and ZmPTI1c were significantly higher under short day than under long day.ZmPTI1c interacted with and phosphorylated ZmMYB31.GSR resistance in zmmyb31 mutant was significantly increased than in wild type,indicating that ZmMYB31 also negatively regulated GSR resistance.Furthermore,ZmMYB31 suppressed the transcriptional activation of ZmPTI1c by ZmPIF4.1.Overall,ZmPIF4.1-ZmPTI1c-ZmMYB31negatively regulates maize immunity to GSR,which is likely modulated by photoperiod.展开更多
The immunohistochemical localization of IAA and the comparison of their relative levels were carried out for the first time in the anthers of Nongken 58S and its wild type Nongken 58 (Oryza sativa subsp. japonica) af...The immunohistochemical localization of IAA and the comparison of their relative levels were carried out for the first time in the anthers of Nongken 58S and its wild type Nongken 58 (Oryza sativa subsp. japonica) after long_day and short_day treatments. The distribution of free_IAA in anthers and its dynamic variation could be reflected by this method. The results showed that the IAA level in the anthers of Nongken 58S after long_day treatment was much lower than that in short_day_treated Nongken 58S and those in wild type Nongken 58 in five stages from pistil and stamen primordia formation to late uninucleate stage. The possible reasons for IAA deficiency in Nongken 58S_LD anthers and its relationship with fertility alteration were also discussed.展开更多
Changes in the pattern of organization of microtubules in the meiotic stages of development of pollen (i.e. from pre-meiotic interphase to more or less metaphase I) of a normal (IR36) and a temperature/photoperiod sen...Changes in the pattern of organization of microtubules in the meiotic stages of development of pollen (i.e. from pre-meiotic interphase to more or less metaphase I) of a normal (IR36) and a temperature/photoperiod sensitive male sterile line (Peiai 64S) of rice were studied using immunofluorescence confocal microscopy. In IR36, from pre-meiotic interphase to metaphase I, the pattern of microtubule distribution in the meiocytes underwent a series of changes. Some new organizational patterns of microtubules (that have not been described before) were observed during microsporogenesis, including the existence of a broad band of perinuclear microtubules at the diakinesis stage of development. The pattern of microtubule distribution in the meiocytes of the male sterile line, Peiai 64S, was quite different front that seen in IR36. In Peiai 64S, the microtubules showed abnormal patterns of distribution from pre-meiotic interphase to metaphase I. For example the broad band of perinuclear microtubules seen at diakinesis in IR36 was much disorganized and loosened in Peiai 64S. The spindles formed were also very abnormal and different from the normal spindle. The appearance of abnormal microtubule distribution in the early stages of microsporogenesis may contribute to the malformation and ultimate abortion of pollen in Peiai 64S.展开更多
[Objective] The study aimed to reveal the effect of photoperiod and temperature on male fertility of cytoplasmic male sterile line Vtai911289a in wheat and discuss the mechanism of male fertility alteration. [ Method ...[Objective] The study aimed to reveal the effect of photoperiod and temperature on male fertility of cytoplasmic male sterile line Vtai911289a in wheat and discuss the mechanism of male fertility alteration. [ Method ] The sowing-date tests and designed conditions were conducted during 2003 -2005. [ Result] Fertility of Vtai911289a, could alter under specific photoperiod and temperature conditions. Temperature is one of the main factors influencing male fertility of the male sterile lines. Vtai911289a, showed stable sterility under the condition of the mean of daily temperature at fertility sensitive stage lower than 19℃ and presented partial fertility when the mean of daily temperature at fertility sensitive stage lower than 20 - 22℃. Photoperiod to some extent affects the male fertility of Vtai911289a, long-day condition is helpful for the male fertility of the sterile line. [ Conclusion] The application of photoperiod temperature-sensitive cytoplasmic male sterile line in production has a higher safety than that of temperature sensitive sterile line.展开更多
Short_day (SD) induced the plant senescence in pumpkin ( Cucurbita pepo Linn.) strain 185. Structural assay, gene expression and a series of biochemical analyses were performed to analyze the senescence mechanism...Short_day (SD) induced the plant senescence in pumpkin ( Cucurbita pepo Linn.) strain 185. Structural assay, gene expression and a series of biochemical analyses were performed to analyze the senescence mechanism in pumpkin strain 185 exposed to SD. Two aspects of important changes initiated in SD exposure contributed to the senescence process. SD functionally led to the initiation of the apical transformation from vegetative to reproductive growth, and then programmed cell death (PCD) in the apical meristem, causing the loss of vigorous growth activity. Moreover, SD treatment resulted in the formation of a great number of dying cells in mesophyll tissue later in the development compared with the phenotype of plants under long_day (LD) conditions. During the senescence process, high expression of nuclease is an important molecular event. These results indicate that the initiation of senescence process in pumpkin stain 185 plants is closely related to the death of cells in apical meristem and mesophyll.展开更多
Reproductive polyphenism,which allows one genotype to produce sexual and asexual morphs,is an extreme case of phenotypic plasticity and is commonly observed in aphids.Aphids are typical species that switch these repro...Reproductive polyphenism,which allows one genotype to produce sexual and asexual morphs,is an extreme case of phenotypic plasticity and is commonly observed in aphids.Aphids are typical species that switch these reproductive modes,and the pathway orientation is triggered by the environmental conditions(mainly photoperiod and temperature).The typical arm ual life of aphids in eludes a successi on of parthenogenetic gen erations duri ng the spri ng and summer and a single sexual generation in autumn.In this review,we describe how the environmental cues orientate the reproductive mode of aphids from photoperiodic perception to endocrine regulation,and how juvenile hormones may act on the target cells(oocytes)to initiate the gametogenesis and embryogenesis in sexual and asexual reproduction.We also discuss the paradox of sex,especially the advantages of sexual reproduction in aphids.With the recent development of genomic resources in aphids,many potential genes involved in the reproductive polyphenism will enter the public's awareness.In particular,we describe a novel RNAi method in aphids,which may provide a molecular technique for determining the developmental fate and multiple reproductive strategies.展开更多
Abstract Melatonin （N-acetyi-5-methoxytryptamine） is a well-known animal hormone, which is synthesized and secreted by pineal gland and takes part in the regulation of circadian rhythm in animals. At present it has ...Abstract Melatonin （N-acetyi-5-methoxytryptamine） is a well-known animal hormone, which is synthesized and secreted by pineal gland and takes part in the regulation of circadian rhythm in animals. At present it has been observed that melatonin is widely existed in higher plants while there have no enough studies on functions of melatonin in plants. Researches have already indicated that the possible functions of melatonin in plants include regulating photoperiod, participating in growth regulation, clearing active oxygen, and promoting activity of antioxidase. General reviews upon functions of melatonin in plants are made upon experiments in recent years. We fo-cus on the demonstrated and predicted biological functions of melatonin in plants to bring researchers up to date on this field. The weakness in present studies and the main research directions are also pointed out.展开更多
On a population level,individual plasticity in reproductive phenology can provoke either anticipations or delays in the average reproductive timing in response to environmental changes.However,a rigid reliance on phot...On a population level,individual plasticity in reproductive phenology can provoke either anticipations or delays in the average reproductive timing in response to environmental changes.However,a rigid reliance on photoperiodism can constraint such plastic responses in populations inhabiting temperate latitudes.The regulation of breeding season length may represent a further tool for populations facing changing environments.Nonetheless,this skill was reported only for equatorial,nonphotoperiodic populations.Our goal was to evaluate whether species living in temperate regions and relying on photoperiodism to trigger their reproduction may also be able to regulate breeding season length.During 10 years,we collected 2,500 female reproductive traits of a mammal model species(wild boar Sus scrofa)and applied a novel analytical approach to reproductive patterns in order to observe population-level variations of reproductive timing and synchrony under different weather and resources availability conditions.Under favorable conditions,breeding seasons were anticipated and population synchrony increased(i.e.,shorter breeding seasons).Conversely,poor conditions induced delayed and less synchronous(i.e.,longer)breeding seasons.The potential to regulate breeding season length depending on environmental conditions may entail a high resilience of the population reproductive patterns against environmental changes,as highlighted by the fact that almost all mature females were reproductive every year.展开更多
Many birds species breed in colonies.One of the species in the Corvidae family nesting in groups is the Rook(Corvus frugilegus).The construction of the nest is costly for birds and needs high energy expenditure.Theref...Many birds species breed in colonies.One of the species in the Corvidae family nesting in groups is the Rook(Corvus frugilegus).The construction of the nest is costly for birds and needs high energy expenditure.Therefore,birds should optimize the time of nest building in relation to environmental,especially weather,conditions.Furthermore,birds should adapt their breeding phenology,including the date of starting the construction of nests for climate change.We observed the dynamics of increasing numbers of nests in a colony of Rooks in relation to air temperature,wind,rainfall,snowfall and day-length(indirect indicator of photoperiodism).Observations were carried out during three breeding seasons(2015-2017)in a large rookery in a big city in north-eastern Poland.The increase in the number of nests was correlated only with day length and no effect of climatic factors on the number of nests in the colony was observed.Number of nests varied significantly between successive years of research.In the case of the Rook(predictable breeders),the photoperiod seems to be the most important factor influencing breeding behavior,especially nest construction.In the last three decades,increasing temperature and time of spring phases have advanced and have influenced changes in the phenology of the availability of food resources.Simultaneously,a rapid decline in the numbers of breeding pairs of the Rook in Poland has been observed,especially in the last three decades.Conservative attachment to the length of the day,which is the main factor responsible for the development of the breeding colony,makes the Rook appear to be a species with low plasticity in the face of rapid climate changes.Thus,we suggest that may indirectly influence the decrease in the breeding population of the Rook.展开更多
Heading date determines the seasonal and regional adaptation of rice(Oryza sativa L.)varieties and is mainly controlled by photoperiod sensitivity(PS).The core heading date genes Hd1,Ghd7,DTH8,and PRR37 act synergisti...Heading date determines the seasonal and regional adaptation of rice(Oryza sativa L.)varieties and is mainly controlled by photoperiod sensitivity(PS).The core heading date genes Hd1,Ghd7,DTH8,and PRR37 act synergistically in regulating the PS.In this study,we systematically analyze the heading date,PS,and agronomic traits of eight homozygous lines with various combinations of Hd1,Ghd7,and DTH8 alleles in the prr37 background under long-day(LD)and short-day(SD)conditions,respectively.We find that Hd1 alone promotes heading,regardless of the day length.However,under LDs,Hd1 suppresses flowering,in coordination with functional Ghd7 or with Ghd7 and DTH8.These loci cooperate to negatively regulate the Ehd1-Hd3 a/RFT1 pathway and delay heading.Under SDs,Hd1 competes with various heading suppressors to promote heading.Therefore,the dual function of Hd1 is vital for PS.The lines carrying Hd1 alone show reduced plant height with fewer primary and secondary branches in panicles.Lines carrying Ghd7 and DTH8(with hd1)show delayed heading and improve agronomic traits.Overall,our results reveal the regulation of rice PS flowering by the core heading date genes and their effects on agronomic traits,providing valuable information for the selection of rice varieties for adaptation to different light and temperature conditions.展开更多
In nature, Apostichopus japonicus exhibits a behavioral characteristic of emerging at night and sheltering during the day. Hence, it was commonly believed that longer and darker light conditions are better for a popul...In nature, Apostichopus japonicus exhibits a behavioral characteristic of emerging at night and sheltering during the day. Hence, it was commonly believed that longer and darker light conditions are better for a population of A. japonicus. In aquaculture situations therefore, animals have commonly been cultured without lighting, especially during juvenile-hatching culture. However, how the length of darkness each day affects .4.japonicus and what the mechanism is of behavioral response of A. japonicus to different photoperiods remain unclear, and are specifically addressed in this study. We applied nine photoperiod treatments （light：dark （LD） cycles at 0：24, 3：21, 6：18, 9：15, 12：12, 15：9, 18：6, 21：3, and 24：0 under 500Ix） to 60 individuals （29.73±0.23 g） per treatment （with 3 replicates）. The enviroramental conditions were set as： water temperature = 16.9±0.3℃, dissolved oxygen〉6.0 rag/L, ammonia〈0.3 mg/L, pH=7.8-8.2, and salinity=30-32. Under experimental conditions of continuous darkness as well as continuous light, cyclic nocturnal activity patterns of A. japonicus （viz. the animals emerged and fed at night and sheltered during the day） were observed. However, they spent more and less time, respectively, moving and feeding under continuous darkness and continuous light, than those under a natural light cycle. Under photoperiods with 6-12 h of light, the animals showed one sheltering behavior transition and two emerging behavior transitions. These behavior transitions appeared to be governed by some internal physiological factors and induced by daily light variation. The behavior of the animals was significantly affected by different photoperiods, and the distribution rate （DR） of the animals emerging at ＂daytime＂ increased with lengthening ＂light time＂ （except for the LD 3：21 cycle）. We also found that there was no significant difference in mean DR per day under LD cycles of 6：18, 9：15, 15：9, and 12：12. Mean DRs per day were significantly lower for these photoperiods, than for those under LD cycles of 0：24 and 3：21, and significantly higher than for those under LD cycles of 18：6, 21：3 and 24：0. These results imply that 6-15 h light per day were the similar photoperiods to natural sunlight. From the viewpoint of activity and feeding behaviors, these might be the optimal photoperiods for rearing A. japonicus.展开更多
基金supported by the National Key Research and Development Plan(2016YFD0101005)National Natural Science Foundation of China(31422041)+1 种基金China Postdoctoral Science Foundation Grant(2014M56013)the Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences
文摘Soybean(Glycine max) is a facultative short-day plant with a sensitive photoperiod perception and reaction system, which allows it to adjust its physiological state and gene regulatory networks to seasonal and diurnal changes in environmental conditions. In the past few decades, soybean cultivation has spread from East Asia to areas throughout the world. Biologists and breeders must now confront the challenge of understanding the molecular mechanism of soybean photoperiodism and improving agronomic traits to enable this important crop to adapt to geographical and environmental changes. In this review, we summarize the genetic regulatory network underlying photoperiodic responses in soybean. Genomic and genetic studies have revealed that the circadian clock, in conjunction with the light perception pathways, regulates photoperiodic flowering. Here, we provide an annotated list of 844 candidate flowering genes in soybean, with their putative biological functions. Many photoperiod-related genes have been intensively selected during domestication and crop improvement. Finally, we describe recent progress in engineering photoperiod-responsive genes for improving agronomic traits to enhance geographic adaptation in soybean, as well as future prospects for research on soybean photoperiodic responses.
基金supported by grants from the Chinese Academy of Sciences(XDA24010101)the Biological Breeding-National Science and Technology Major Project(2024ZD04077)+2 种基金the National Key Research and Development Program of China(2023YFF1001200)Natural Science Foundation of Zhejiang Province(LD24C130001)the Agricultural Science and Technology Innovation Program(ASTIP)of CAAS。
文摘A later heading date generally leads to higher grain yield in favorable ecological regions;however,grain yield reaches a limit as the heading date exceeds a certain threshold.Ghd7 is the first cloned major gene that regulates heading date,plant height and grain number.Here,we investigated the relationship between Ghd7 and florigen genes Hd3a and RFT1,to determine their roles in regulating heading date and grain number under different photoperiods.Our results revealed that under long-day(LD)conditions,Hd3a acts prior to RFT1 to promote heading while negatively regulating plant height and grain number.In contrast,Ghd7 positively regulates heading date,plant height,and grain number by inhibiting both Hd3a and RFT1.Under short-day(SD)conditions,the functions of Hd3a and RFT1 remain consistent with those under LD conditions,but Ghd7 does not inhibit their expression,resulting in a weaker phenotypic effect compared to Hd3a.Additionally,under both LD and SD conditions,increased Ghd7 expression enhances its inhibitory effect on Hd3a and RFT1,leading to later heading and increased grain number;however,once the heading date exceeds 94 d,grain number no longer increases.Moreover,the gn1a allele increased grain number by 16.5%to 42.5%,while combinations of the elite alleles from Ghd7,Hd3a,RFT1,and Gn1a significantly increased grain number by up to 240.9%.Therefore,we propose a new breeding strategy to optimize the heading date and grain number using the Ghd7Hd3aRFT1gn1a combination of Ghd7,Hd3a,RFT1,and Gn1a under LD conditions,and the Ghd7hd3aRFT1gn1a combination under SD conditions.This strategy improved the yield of the high-quality Northeast variety Kongyu 131(KY131)by 69.1%in Beijing and 93.7%in Hainan.This strategy will greatly improve the efficiency of north-to-south adaptation in rice,providing theoretical guidance for expanding the geographical adaptability of rice varieties.
基金supported by the Ministry of Science and Technology(No:2019FY101602).
文摘Climate warming is reshaping the phenology of plants in recent decades,with potential implications for forest productivity,carbon sequestration,and ecosystem functioning.While the effects of warming on secondary growth phenology is becoming increasingly clear,the influenceof environmental factors on different developmental phases of xylem remains to be quantified.In this study,we investigated the temporal dynamics of xylem cell enlargement,wall-thickening,and the interval between these events in twelve temperate tree species from Northeast China over the period 2019–2024.We found that both cell enlargement and wall-thickening advanced significantlyin response to climate warming,with species-specific variations in the rate of advancement.Importantly,the advancing rate of wallthickening was greater than that of cell enlargement,leading to a shortening of the interval between these two events.Linear mixed-effects models revealed that photoperiod,forcing temperature,and precipitation were the primary environmental drivers influencingthe timing of both cell enlargement and wall-thickening,with photoperiod emerging as the most important factor.These results suggest that climate warming accelerates the heat accumulation required for the transition from xylem cell enlargement to wall-thickening,thereby shortening the time interval between these two developmental stages.Beyond contributing valuable multi-year xylem phenological data,our results provide mechanistic insights that enhance predictions of wood formation dynamics under future climate scenarios and improve the accuracy of forest carbon models.
基金supported by grants from the National Natural Science Foundation of China(32172547).
文摘Photoperiod and temperature are crucial factors that trigger flowering in Brassica juncea(B.juncea).However,the underlying regulatory mechanisms remain poorly understood.The MADS-box transcription factor AGL18 acts as a pivotal repressor of floral transition and functions redundantly with AGL15.In this study,we isolated BjuAGL18-1 from B.juncea and identified two unique transcripts,resulting in two distinct proteins:a full-length protein,BjuAGL18-1L,and a truncated protein,BjuAGL18-1S.Further investigation showed that the two isoforms had similar subcellular localizations but different expression patterns in various plant tissues.Notably,BjuAGL18-1L and BjuAGL18-1S were abundantly induced under short-and long-day photoperiods,respectively.BjuAGL18-1L overexpression in B.juncea and Arabidopsis thaliana(A.thaliana)led to late flowering,whereas BjuAGL18-1S overexpression resulted in early flowering.Yeast two-hybrid,bimolecular fluorescent complementation,and luciferase complementation assays showed that BjuAGL18-1L,but not BjuAGL18-1S(which lacked the EAR motif),interacted with the co-repressor BjuAFR2 and the histone deacetylase BjuHDA9 to form a multiprotein complex.Further analysis indicated that BjuAGL18-1L could also form a complex with BjuAGL15 and bind to the BjuFUL promoter,thus inhibiting its expression.However,BjuAGL18-1S interacted with BjuAGL18-1L to form heterodimers,which attenuated their activities,likely by disrupting their binding to target genes,resulting in accelerated flowering progression.These results suggest that BjuAGL18-1 is involved in photoperiod-induced flowering via different regulatory mechanisms in B.juncea.
基金The Science and Technology Plan of Dalian under contract Nos 2023RO058 and 2022RQ060the Liaoning Province Natural Science Planning Fund Project under contract No. 2022-BS-273+1 种基金the Liaoning Provincial Department of Education Basic Research Project under contract No. LJKQZ20222357the Discipline Construction Funding for Marine Science Subject of Dalian Ocean University。
文摘Mandarin fish(Siniperca scherzeri) has high market prices and significant market potential in China because of its highquality meat and high nutritional value. However, due to the limited scale of aquaculture, meeting the market demand is difficult, making the effective development of the aquaculture potential of mandarin fish an important challenge for the industry. In this study, a 30-d breeding experiment was conducted on mandarin fish larvae under three photoperiod conditions: G1 8 h light:16 h dark(8L:16D), G2 12 h light:12 h dark(12L:12D), and G3 16 h light:8 h dark(16L:8D). The results showed that the G2 group exhibited the best growth performance and development status, with final body weights, weight gain rates, and specific growth rates all higher than those of the other two groups(P < 0.05). Observations of sections from each group revealed that the intestinal villi length and muscle thickness of the G2 group were significantly greater than those of the other two groups(P < 0.05). The G2 group inhibited the transcriptional activation of key circadian rhythm genes, including nr1d2a, nr1d1 and per1, while upregulating the expression of BMAL1 in S. scherzeri.The activation of both the insulin signalling pathway and the Fox O signalling pathway enhanced the efficient secretion of insulin, which subsequently played a critical role in regulating fatty acid metabolism. This active fatty acid metabolism provided an optimal energy supply, ensuring that other nutrients were fully utilized during the growth and development process while minimizing unnecessary nutrient loss. Consequently, this mechanism effectively promoted the overall growth and development of S. scherzeri. This study was the first to elucidate the transcriptomic expression patterns of S. scherzeri under varying photoperiod conditions. In response to the cyclic alternation of day and night, S. scherzeri regulated their metabolic levels and the transcriptional activation of downstream target genes via insulin signalling.
基金supported by the National Natural Science Foundation of China(32101759,32241042)the National Key Research and Development Program of China(2023YFD1200700 and 2023YFD1200704).
文摘Foxtail millet(Setaria italica)is an important crop and an emerging model plant.Photoperiodic flowering is a key determinant of its production and geographic expansion.In this study,we found that SiPRR37 is responsible for the major quantitative trait locus(QTL)Heading date 2(Hd2)identified in 680 foxtail millets using a genome-wide association study.Overexpression of SiPRR37 in foxtail millet significantly delayed the heading date under both natural long-day and short-day conditions.CRISPR/Cas9-induced Siprr37 mutants exhibited earlier flowering in long-day conditions but later flowering in short-day conditions.The critical day length(CDL)for the reversal of Siprr37’s function was around 14.3 h.Haplotype analysis revealed that accessions with the Tc1-Mariner transposon insertion in SiPRR37(Hap 1)flowered significantly earlier at higher latitudes,and later at lower latitudes,indicating that natural variants of SiPRR37 exert dual functions in flowering regulation according to geographic latitude.The gradual,successive decrease in the frequency of Hap 2 from low to high latitudes,with the concurrent increase of Hap 1,demonstrates that these haplotypes have undergone artificial selection.Further FST analysis demonstrated that SiPRR37 has contributed to the ecological adaption of foxtail millet.Additionally,we reveal that OsPRR37 promotes flowering in rice,while GmPRR37 may only inhibit flowering in soybean.Further diurnal expression and transgenic analyses suggest that the dual function of SiPRR37 might depend on SiHd1.Our study uncovered the distinct functional reversal of SiPRR37 and functional diversification of PRR37 homologs in SD crops.These findings not only enrich knowledge about the regulation of photoperiodic flowering,but also contribute to genetic improvement of crops’regional adaptability.
基金funded by the USDA National Institute of Food and Agriculture(USDA-NIFA)through the APPS grant(Advancing Populus Pathways in the Southeast,2018-68005-27636)United States Department of Energy(DOE)through the PoSIES(Populus in the Southeast for Integrated Ecosystem Services,DE-EE0009280)USDA-NIFA McIntire Stennis grant(MISZ-067050).
文摘Understanding the phenology and productivity of Populus species is crucial for effective management and conservation strategies amid climate change.We investigated leaf budbreak timing,susceptibility to cold damage,leaf dynamics,and biomass production of 168 Populus genotypes with diverse provenances in the southeastern United States.Our study revealed significant variation in budbreak timing across different taxa and years,with genotypes inheriting traits adapted to their parents’local climates.Temperature emerged as a key factor triggering budbreak,while leaf development depended on other environmental cues such as photoperiod.Notably,budbreak occurred approximately 20 days earlier in 2023 compared to 2022 due to higher accumulated degree days(ADDs).Short-rotation-coppice(SRC)management delayed budbreak by five to ten days.Cold damage was significant in 2023,particularly for genotypes from northern provenances and those with P.maximowiczii parentage.Severe damage was also observed in eastern cottonwood(Populus deltoides×Populus deltoides(D×D))genotypes,despite most having southeastern US parentages.Leaf dynamics,including leaf duration and leaf area index(LAI),varied across taxa and sites,with earlier budbreak correlating with extended growing seasons and increased LAI.Biomass production was intricately linked to phenological events,with earlier budbreak leading to increased biomass production and greater susceptibility to cold damage.Our findings highlight the importance of genetics,environment,and coppicing management in understanding and managing Populus phenology and biomass production.These insights provide valuable guidance for developing effective breeding,conservation,and management strategies for Populus species in the context of climate change.
基金supported by the Zhongshan Biological Breeding Laboratory,China(Grant No.ZSBBL-KY2023-07)the Jiangsu Agricultural Science and Technology Innovation Fund,China(Grant No.CX(22)3138)+1 种基金the National Natural Science Foundation of China(Grant Nos.32101736,32002124)the Jiangsu Provincial Key Research and Development Program,China(Grant No.BE2021360-2).
文摘The photoperiod/thermo-sensitive genic male sterility(P/TGMS)system is crucial for hybrid rice production,but challenges persist in seed purity(due to fertility conversion and mixed male seeds)and mechanization.Here,we developed a novel hybrid seed production scheme using herbicide-resistance alleles(OsALS and CYP81A6).P/TGMS lines were bred for imazamox sensitivity and bentazon resistance,while male parents were engineered for the opposite traits.This system enables mechanical harvesting and ensures hybrid purity by eliminating self-pollinated contaminants through herbicide application.We identified suitable sterile lines and developed complementary male parents via breeding and CRISPR/Cas9 editing,validated through herbicide assays.This strategy enhances hybrid seed purity and mechanization efficiency in two-line hybrid rice production.
基金supported financially by the grants from the JBGS[2021]002 project from the Jiangsu Governmentthe National Nature Science Foundation of China(32472095)+2 种基金the National Key Research and Development Program of China(2020YFE02029002)Collaborative Innovation Center for Modern Crop Production(CIC-MCP)to Xiquan Gaosupported in part by the high-performance computing platform of Bioinformatics Center,Nanjing Agricultural University。
文摘Gibberella stalk rot(GSR)caused by Fusarium graminearum is one of the most devastating diseases of maize,seriously impacting maize yield and quality,as well as the ability to use technology of mechanical harvesting.Environmental conditions including photoperiod affect crop disease resistance.However,the mechanism underlying photoperiod-regulated maize GSR resistance remains unexplored.We found in this study that GSR resistance is regulated by the ZmPIF4.1(Phytochrome-Interacting Factor4)-ZmPTI1c(Pto-Interacting 1)-ZmMYB31 module coupled with photoperiod.The functional analysis of zmpti1c mutant indicated that ZmPTI1c negatively regulates maize GSR resistance.Short day promoted the disease progression in both zmpti1c and wild-type plants.ZmPTI1c promoter contains multiple predicted cis-acting elements for light responses.Yeast one-hybrid assay(Y1H),Electrophoretic mobility shift analysis(EMSA),and Dual-luciferase(LUC)reporter assays demonstrated that ZmPIF4.1 binds to the G-box in ZmPTI1c promoter and activates its expression.Moreover,expression levels of ZmPIF4 and ZmPTI1c were significantly higher under short day than under long day.ZmPTI1c interacted with and phosphorylated ZmMYB31.GSR resistance in zmmyb31 mutant was significantly increased than in wild type,indicating that ZmMYB31 also negatively regulated GSR resistance.Furthermore,ZmMYB31 suppressed the transcriptional activation of ZmPTI1c by ZmPIF4.1.Overall,ZmPIF4.1-ZmPTI1c-ZmMYB31negatively regulates maize immunity to GSR,which is likely modulated by photoperiod.
文摘The immunohistochemical localization of IAA and the comparison of their relative levels were carried out for the first time in the anthers of Nongken 58S and its wild type Nongken 58 (Oryza sativa subsp. japonica) after long_day and short_day treatments. The distribution of free_IAA in anthers and its dynamic variation could be reflected by this method. The results showed that the IAA level in the anthers of Nongken 58S after long_day treatment was much lower than that in short_day_treated Nongken 58S and those in wild type Nongken 58 in five stages from pistil and stamen primordia formation to late uninucleate stage. The possible reasons for IAA deficiency in Nongken 58S_LD anthers and its relationship with fertility alteration were also discussed.
文摘Changes in the pattern of organization of microtubules in the meiotic stages of development of pollen (i.e. from pre-meiotic interphase to more or less metaphase I) of a normal (IR36) and a temperature/photoperiod sensitive male sterile line (Peiai 64S) of rice were studied using immunofluorescence confocal microscopy. In IR36, from pre-meiotic interphase to metaphase I, the pattern of microtubule distribution in the meiocytes underwent a series of changes. Some new organizational patterns of microtubules (that have not been described before) were observed during microsporogenesis, including the existence of a broad band of perinuclear microtubules at the diakinesis stage of development. The pattern of microtubule distribution in the meiocytes of the male sterile line, Peiai 64S, was quite different front that seen in IR36. In Peiai 64S, the microtubules showed abnormal patterns of distribution from pre-meiotic interphase to metaphase I. For example the broad band of perinuclear microtubules seen at diakinesis in IR36 was much disorganized and loosened in Peiai 64S. The spindles formed were also very abnormal and different from the normal spindle. The appearance of abnormal microtubule distribution in the early stages of microsporogenesis may contribute to the malformation and ultimate abortion of pollen in Peiai 64S.
文摘[Objective] The study aimed to reveal the effect of photoperiod and temperature on male fertility of cytoplasmic male sterile line Vtai911289a in wheat and discuss the mechanism of male fertility alteration. [ Method ] The sowing-date tests and designed conditions were conducted during 2003 -2005. [ Result] Fertility of Vtai911289a, could alter under specific photoperiod and temperature conditions. Temperature is one of the main factors influencing male fertility of the male sterile lines. Vtai911289a, showed stable sterility under the condition of the mean of daily temperature at fertility sensitive stage lower than 19℃ and presented partial fertility when the mean of daily temperature at fertility sensitive stage lower than 20 - 22℃. Photoperiod to some extent affects the male fertility of Vtai911289a, long-day condition is helpful for the male fertility of the sterile line. [ Conclusion] The application of photoperiod temperature-sensitive cytoplasmic male sterile line in production has a higher safety than that of temperature sensitive sterile line.
文摘Short_day (SD) induced the plant senescence in pumpkin ( Cucurbita pepo Linn.) strain 185. Structural assay, gene expression and a series of biochemical analyses were performed to analyze the senescence mechanism in pumpkin strain 185 exposed to SD. Two aspects of important changes initiated in SD exposure contributed to the senescence process. SD functionally led to the initiation of the apical transformation from vegetative to reproductive growth, and then programmed cell death (PCD) in the apical meristem, causing the loss of vigorous growth activity. Moreover, SD treatment resulted in the formation of a great number of dying cells in mesophyll tissue later in the development compared with the phenotype of plants under long_day (LD) conditions. During the senescence process, high expression of nuclease is an important molecular event. These results indicate that the initiation of senescence process in pumpkin stain 185 plants is closely related to the death of cells in apical meristem and mesophyll.
基金This work was supported by the National Key Research and Development Program of China(2018YFD0200804 and 2017YFD0201200).
文摘Reproductive polyphenism,which allows one genotype to produce sexual and asexual morphs,is an extreme case of phenotypic plasticity and is commonly observed in aphids.Aphids are typical species that switch these reproductive modes,and the pathway orientation is triggered by the environmental conditions(mainly photoperiod and temperature).The typical arm ual life of aphids in eludes a successi on of parthenogenetic gen erations duri ng the spri ng and summer and a single sexual generation in autumn.In this review,we describe how the environmental cues orientate the reproductive mode of aphids from photoperiodic perception to endocrine regulation,and how juvenile hormones may act on the target cells(oocytes)to initiate the gametogenesis and embryogenesis in sexual and asexual reproduction.We also discuss the paradox of sex,especially the advantages of sexual reproduction in aphids.With the recent development of genomic resources in aphids,many potential genes involved in the reproductive polyphenism will enter the public's awareness.In particular,we describe a novel RNAi method in aphids,which may provide a molecular technique for determining the developmental fate and multiple reproductive strategies.
基金Supported by National 863 Project of China(2012AA101801)"Twelfth Five-Year"Plan for Science&Technology Project(2011BAD17B01)Chinese Universities Scientific Fund(2009-2-06)~~
文摘Abstract Melatonin （N-acetyi-5-methoxytryptamine） is a well-known animal hormone, which is synthesized and secreted by pineal gland and takes part in the regulation of circadian rhythm in animals. At present it has been observed that melatonin is widely existed in higher plants while there have no enough studies on functions of melatonin in plants. Researches have already indicated that the possible functions of melatonin in plants include regulating photoperiod, participating in growth regulation, clearing active oxygen, and promoting activity of antioxidase. General reviews upon functions of melatonin in plants are made upon experiments in recent years. We fo-cus on the demonstrated and predicted biological functions of melatonin in plants to bring researchers up to date on this field. The weakness in present studies and the main research directions are also pointed out.
基金The Provincial Administration of Arezzo and the Italian Ministry of Education,University and Research(PRIN 2010-2011,20108 TZKHC)financially and logistically supported the research.S.G.was supported by the FAR 2020 of the University of Sassari.
文摘On a population level,individual plasticity in reproductive phenology can provoke either anticipations or delays in the average reproductive timing in response to environmental changes.However,a rigid reliance on photoperiodism can constraint such plastic responses in populations inhabiting temperate latitudes.The regulation of breeding season length may represent a further tool for populations facing changing environments.Nonetheless,this skill was reported only for equatorial,nonphotoperiodic populations.Our goal was to evaluate whether species living in temperate regions and relying on photoperiodism to trigger their reproduction may also be able to regulate breeding season length.During 10 years,we collected 2,500 female reproductive traits of a mammal model species(wild boar Sus scrofa)and applied a novel analytical approach to reproductive patterns in order to observe population-level variations of reproductive timing and synchrony under different weather and resources availability conditions.Under favorable conditions,breeding seasons were anticipated and population synchrony increased(i.e.,shorter breeding seasons).Conversely,poor conditions induced delayed and less synchronous(i.e.,longer)breeding seasons.The potential to regulate breeding season length depending on environmental conditions may entail a high resilience of the population reproductive patterns against environmental changes,as highlighted by the fact that almost all mature females were reproductive every year.
文摘Many birds species breed in colonies.One of the species in the Corvidae family nesting in groups is the Rook(Corvus frugilegus).The construction of the nest is costly for birds and needs high energy expenditure.Therefore,birds should optimize the time of nest building in relation to environmental,especially weather,conditions.Furthermore,birds should adapt their breeding phenology,including the date of starting the construction of nests for climate change.We observed the dynamics of increasing numbers of nests in a colony of Rooks in relation to air temperature,wind,rainfall,snowfall and day-length(indirect indicator of photoperiodism).Observations were carried out during three breeding seasons(2015-2017)in a large rookery in a big city in north-eastern Poland.The increase in the number of nests was correlated only with day length and no effect of climatic factors on the number of nests in the colony was observed.Number of nests varied significantly between successive years of research.In the case of the Rook(predictable breeders),the photoperiod seems to be the most important factor influencing breeding behavior,especially nest construction.In the last three decades,increasing temperature and time of spring phases have advanced and have influenced changes in the phenology of the availability of food resources.Simultaneously,a rapid decline in the numbers of breeding pairs of the Rook in Poland has been observed,especially in the last three decades.Conservative attachment to the length of the day,which is the main factor responsible for the development of the breeding colony,makes the Rook appear to be a species with low plasticity in the face of rapid climate changes.Thus,we suggest that may indirectly influence the decrease in the breeding population of the Rook.
基金supported by grants from the National Natural Science Foundation of China (31921004 and 31871596)the Major Program of Guangdong Basic and Applied Research (2019B030302006)the Laboratory of Lingnan Modern Agriculture Project (NT2021002)
文摘Heading date determines the seasonal and regional adaptation of rice(Oryza sativa L.)varieties and is mainly controlled by photoperiod sensitivity(PS).The core heading date genes Hd1,Ghd7,DTH8,and PRR37 act synergistically in regulating the PS.In this study,we systematically analyze the heading date,PS,and agronomic traits of eight homozygous lines with various combinations of Hd1,Ghd7,and DTH8 alleles in the prr37 background under long-day(LD)and short-day(SD)conditions,respectively.We find that Hd1 alone promotes heading,regardless of the day length.However,under LDs,Hd1 suppresses flowering,in coordination with functional Ghd7 or with Ghd7 and DTH8.These loci cooperate to negatively regulate the Ehd1-Hd3 a/RFT1 pathway and delay heading.Under SDs,Hd1 competes with various heading suppressors to promote heading.Therefore,the dual function of Hd1 is vital for PS.The lines carrying Hd1 alone show reduced plant height with fewer primary and secondary branches in panicles.Lines carrying Ghd7 and DTH8(with hd1)show delayed heading and improve agronomic traits.Overall,our results reveal the regulation of rice PS flowering by the core heading date genes and their effects on agronomic traits,providing valuable information for the selection of rice varieties for adaptation to different light and temperature conditions.
基金Supported by the National Natural Science Foundation of China (Nos. 30871931, 30771661)the National Key Technology Research and Development Program of China (Nos. 2006BAD09A01)the National Special Research Fund for Non-Profit Sector (No. 200905020)
文摘In nature, Apostichopus japonicus exhibits a behavioral characteristic of emerging at night and sheltering during the day. Hence, it was commonly believed that longer and darker light conditions are better for a population of A. japonicus. In aquaculture situations therefore, animals have commonly been cultured without lighting, especially during juvenile-hatching culture. However, how the length of darkness each day affects .4.japonicus and what the mechanism is of behavioral response of A. japonicus to different photoperiods remain unclear, and are specifically addressed in this study. We applied nine photoperiod treatments （light：dark （LD） cycles at 0：24, 3：21, 6：18, 9：15, 12：12, 15：9, 18：6, 21：3, and 24：0 under 500Ix） to 60 individuals （29.73±0.23 g） per treatment （with 3 replicates）. The enviroramental conditions were set as： water temperature = 16.9±0.3℃, dissolved oxygen〉6.0 rag/L, ammonia〈0.3 mg/L, pH=7.8-8.2, and salinity=30-32. Under experimental conditions of continuous darkness as well as continuous light, cyclic nocturnal activity patterns of A. japonicus （viz. the animals emerged and fed at night and sheltered during the day） were observed. However, they spent more and less time, respectively, moving and feeding under continuous darkness and continuous light, than those under a natural light cycle. Under photoperiods with 6-12 h of light, the animals showed one sheltering behavior transition and two emerging behavior transitions. These behavior transitions appeared to be governed by some internal physiological factors and induced by daily light variation. The behavior of the animals was significantly affected by different photoperiods, and the distribution rate （DR） of the animals emerging at ＂daytime＂ increased with lengthening ＂light time＂ （except for the LD 3：21 cycle）. We also found that there was no significant difference in mean DR per day under LD cycles of 6：18, 9：15, 15：9, and 12：12. Mean DRs per day were significantly lower for these photoperiods, than for those under LD cycles of 0：24 and 3：21, and significantly higher than for those under LD cycles of 18：6, 21：3 and 24：0. These results imply that 6-15 h light per day were the similar photoperiods to natural sunlight. From the viewpoint of activity and feeding behaviors, these might be the optimal photoperiods for rearing A. japonicus.
