Effects of potassium nutrition on fruit development and yield of substrate grown strawberry

　Effect of K nutrition on sugar and organic acid concentration in fruit and yield of strawberry cultivars (Fragaria ×ananassa Duch.; Nyoho, Toyonoka, Sachinoka, Asukarubi, Akihime, Tochiotome, and Sagahonoka) was investigated. Nutrient solution (NO3 8, NH4 1, P 1, K 4, Ca 2, Mg 1, SO4 1 ; mM) was modified to contain 0 to 4mM of K by replacing K with Ca and supplied from the beginning of flowering. K in the drainage decreased to a trace level 3 weeks after the beginning of treatment except for 4mM‒K solution. Absorption of NO3 apparently decreased in plants supplied 0mM‒K solution, but little difference was observed among the other 3 solutions. K concentration in petiole decreased linearly with decrease in K concentration in solutions, but there was little difference between the concentrations of leaflet of plants supplied with 4 and 2mM‒K solutions. No difference was observed in concentrations of sugars and organic acids in fruit in primary inflorescence. In the second inflorescence, organic acids and K concentration in fruit linearly decreased with decrease in K in supplied solutions while sugar concentration of fruit decreased significantly only in plants supplied 0mM‒K solution. When 0.5 to 4mM‒K solutions were supplied from 2 weeks after planting, marketable fruit yield was smallest in plants supplied 0.5mM‒K solution followed, by that supplied 1mM‒K solution, and largest in that supplied with 2mM‒K solution. Almost all K supplied with 2mM‒K solution was absorbed by strawberry plants and no difference was observed in quality and K concentration of fruit, yield and plant growth between the plants supplied with 2 and 4mM‒K solutions. It may be suitable to reduce the concentration of K in nutrient solution by half for substrate production of strawberry

Non-Universal Finite Size Effects with Universal Infinite-Size Free Energy for the α\alpha-XY model

We study finite size effects in a family of systems in which a parameter controls interaction-range. In the long-range regime where the infinite-size free energy is universal, we show that the finite size effects are not universal but depend on the interaction-range. The finite size effects are observed through discrepancies between time-averages of macroscopic variables in Hamiltonian dynamics and canonical averages of ones with infinite degrees of freedom. For a high energy regime, the relation to a pair of the discrepancies is theoretically predicted and numerically confirmed. We also numerically show that the finite-size effects of macroscopic variables in the canonical ensemble are close to ones in the dynamical systems.Comment: Proceedings of the workshop Comlexty and Nonextensivity - New Trends in Statistical Mechancs - (CN-Kyoto

Defoliating to 12-15 leaves increases calcium concentration and decreases blossom-end rot incidence in fruit of tomato plant grown under moderate water stress

The objectives of this study were to (i) determine the optimum number of whole leaves to retain on a tomato plant for effective blossom-end rot (BER) management and (ii) explore the relationship between shoot calcium (Ca) and fruit Ca in non-defoliated plants in two different sized fruit cultivars, a large-fruited cultivar ‘Momotaro fight’ and a medium-fruited cultivar ‘Cindy sweet’. Treatments involved maintaining 18, 15 and 12 leaves on a plant. All lateral shoots were removed regularly throughout the growing period except the shoot closest to the flowering truss in the 18-leaf treatment. At the length of 10cm, these shoots were sampled for real time Ca determination using a hand held Ca2+ meter. In the plants defoliated to 18 leaves, BER was higher in ‘Momotaro fight’ at 10% compared to 2% in ‘Cindy sweet’. Fruit growth rate was significantly increased by defoliation in ‘Momotaro fight’, however no significant difference was observed among treatments in ‘Cindy sweet’. Defoliating to 12 leaves increased daily Ca transport rate by 59% and 37% in ‘Momotaro fight’ and ‘Cindy sweet’, respectively. Defoliating to 12 leaves increased the water-soluble Ca concentration in the distal part of fruit by 34% and 14% in ‘Momotaro fight’ and ‘Cindy sweet’, respectively. In the plants defoliated to 18 leaves where only old yellowish leaves were removed, a significant steady decrease was observed in the concentration of water soluble Ca in the distal part of fruit with increase in truss order. There was a significant linear relationship between water-soluble Ca concentration in the distal part of the fruit and Ca concentration in the lateral shoot of plants defoliated to 18 leaves. We conclude that under moderate water stress by root zone restriction and also certain other BER inductive conditions, defoliation to 12–15 leaves on a tomato plant should be a promising approach for decreasing BER incidence in susceptible large fruit cultivars

Enhanced O-GlcNAcylation Mediates Cytoprotection under Proteasome Impairment by Promoting Proteasome Turnover in Cancer Cells

The proteasome is a therapeutic target in cancer, but resistance to proteasome inhibitors often develops owing to the induction of compensatory pathways. Through a genome-wide siRNA screen combined with RNA sequencing analysis, we identified hexokinase and downstream O-GlcNAcylation as cell survival factors under proteasome impairment. The inhibition of O-GlcNAcylation synergistically induced massive cell death in combination with proteasome inhibition. We further demonstrated that O-GlcNAcylation was indispensable for maintaining proteasome activity by enhancing biogenesis as well as proteasome degradation in a manner independent of Nrf1, a well-known compensatory transcription factor that upregulates proteasome gene expression. Our results identify a pathway that maintains proteasome function under proteasome impairment, providing potential targets for cancer therapy

Fasciation in Strawberry Floral Organs and Possible Implications for Floral Transition

Fasciation in strawberry is characterized by an enlarged and flattened receptacle, clustering of flowers, and altered inflorescence architecture. However, the developmental process of fasciated flowers remains obscure. In this study, the fasciation incidence and developmental process in the primary fruit and inflorescence architecture were evaluated and compared for the non-susceptible cultivars, ‘Nyoho’ and ‘Sagahonoka’ and one of the most susceptible cultivars, ‘Ai-Berry’. The severity and frequency of flower and inflorescence fasciation was clearly greater in the vigorously growing large plants of ‘Ai-Berry’ compared to small plants and large plants of the other two cultivars. In ‘Ai-Berry’, the deformation of the large shoot apical meristem (SAM) into an oval shape was the initial symptom observed before and during floral transition. Such oval-shaped SAMs often differentiated two or more leaf primordia almost at the same time, which then developed into divided multiple vegetative SAMs before floral transition and linearly-fasciated SAMs during floral transition, respectively. The development of fasciation symptoms was observed after downregulation of FaTFL1. Although inflorescence or receptacle fasciation could be controlled when early and rapid floral induction was achieved by intermittent low-temperature treatment, severe fasciation was observed in late-flowered plants which were either not responsive or not subjected to this treatment. These results indicate that fasciation of floral organs may be triggered and develop during floral transition and that temperature fluctuations around boundary values between floral inhibition to induction may cause a half-finished or slowly processed floral transition and finally result in severe fasciation in vigorously growing ‘Ai-Berry’ plants

Linking Antarctic glaciochemical records to past climate conditions (scientific paper)

Deep Antarctic ice cores document the former states of the climatic system, the atmosphere, and the marine and terrestrial biospheres. However, questions do remain in the interpretation and the reliability of ice core chemical profiles in terms of atmospheric information. Data from the Dome C, Vostok, Dome F, and EPICA deep ice cores are used and compared in the discussions. First of all, the transfer functions of various gaseous and particulate compounds are not entirely understood and in the case of acid gases, strong post-deposition effects are observed at central Antarctic sites. It is emphasised that marine primary and secondary aerosol species may strongly interact during their long-range transport. Continental aerosol is important for the Antarctic impurity budget only in glacial environmental conditions. Its composition, as derived from Antarctic ice core glaciochemistry is discussed. As for the case of marine aerosol, the reaction of primary and gas-derived aerosol has to be considered. Finally, the possible impact of continental dust on marine biogenic activity shortly is discussed in the light of glaciochemical results

Positional differences of intronic transposons in pAMT affect the pungency level in chili pepper through altered splicing efficiency

トウガラシの辛味レベルを変化させる遺伝子変異を発見 －激辛・中辛・辛くないを作り分ける－. 京都大学プレスリリース. 2019-08-30.Capsaicinoids are unique compounds that give chili pepper fruits their pungent taste. Capsaicinoid levels vary widely among pungent cultivars, ranging from low‐pungency to extremely pungent. However, the molecular mechanisms underlying its quantitative variation have not been elucidated. Our previous study identified various loss‐of‐function alleles of the pAMT gene, which led to low‐pungency. The mutations in these alleles are commonly defined by Tcc transposon insertion and its footprint. In this study, we identified two leaky pamt alleles (pamtL1 and pamtL2) with different levels of pAMT activity. Notably, both alleles had a Tcc transposon insertion in intron 3, but the locations of the insertions within the intron were different. Genetic analysis revealed that pamtL1, pamtL2 and a loss‐of‐function pamt allele reduced capsaicinoid levels to about 50%, 10%, and less than 1%, respectively. pamtL1 and pamtL2 encoded functional pAMT proteins, but they exhibited lower transcript levels compared with the functional‐type. RNA‐seq analysis showed that intronic transposons disrupted splicing in intron 3, which resulted in simultaneous expression of functional pAMT mRNA and non‐functional splice variants containing partial sequences of Tcc. The non‐functional splice variants were more dominant in pamtL2 than that in pamtL1. This suggested that the difference in position of the intronic transposons could alter splicing efficiency, which led to different pAMT activities and reduced capsaicinoid content to different levels. Our results provide a striking example where intronic transposons caused allelic variations, which contributed to quantitative differences in secondary metabolite contents

Fecal microbiota transplantation prevents Candida albicans from colonizing the gastrointestinal tract

Gut microbes symbiotically colonize the gastrointestinal (GI) tract, interacting with each other and their host to maintain GI tract homeostasis. Recent reports have shown that gut microbes help protect the gut from colonization by pathogenic microbes. Here, we report that commensal microbes prevent colonization of the GI tract by the pathogenic fungus, Candida albicans. Wild‐type specific pathogen‐free (SPF) mice are resistant to C. albicans colonization of the GI tract. However, administering certain antibiotics to SPF mice enables C. albicans colonization. Quantitative kinetics of commensal bacteria are inversely correlated with the number of C. albicans in the gut. Here, we provide further evidence that transplantation of fecal microbiota is effective in preventing Candida colonization of the GI tract. These data demonstrate the importance of commensal bacteria as a barrier for the GI tract surface and highlight the potential clinical applications of commensal bacteria in preventing pathogenic fungal infections.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149500/1/mim12680_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149500/2/mim12680.pd

トウガラシ（Capsicum baccatum）における カプサイシノイド含量の変異とその非辛味系統

The chili pepper (Capsicum) is both an important spice and fresh vegetable worldwide. C. baccatum is a lesser known domesticated species that is native to the Andean region. Fruit traits such as color, shape, and pungency markedly vary in this species. C. baccatum has potential as a bioresource for future chili pepper breeding programs. Although extensive studies have been conducted on the pungency of C. annuum, that of C. baccatum has not been examined in as much detail. In the present study, capsaicinoid contents were analyzed in 36 C. baccatum accessions. Capsaicinoid contents ranged between 0 and 4,258 μg/gDW. Furthermore, a negative relationship was observed between capsaicinoid contents and fruit weights. Although the pungency of C. baccatum is regarded as low-mild, very few non-pungent accessions were detected ; only one non-pungent accession (‘Kaleidoscope’) was identified among the C. baccatum accessions examined. In order to validate the stability of non-pungency in the accession, capsaicinoid contents were determined at different harvest dates, along with other accessions with different pungencies. Although capsaicinoid contents in other C. baccatum accessions changed with the picking date, capsaicinoid was not detected in ‘Kaleidoscope’ at any date. The non-pungent accession reported here may be useful for future C. baccatum pepper breeding programs.　トウガラシ（Capsicum 属）は世界的に重要な香辛料および野菜である．C. baccatum は南米原産のマイナーな栽培種であるが，果色，果形や辛味など果実形質に多様性が認められることから，トウガラシ遺伝資源として注目されている．トウガラシの辛味性についてはC. annuum 種において多くの研究が行われているが，C. baccatum 種においては十分研究されていない． 　本研究では，C. baccatum 36系統について辛味成分カプサイシノイドの含量を調査した．カプサイシノイド含量の幅は0 ～4,258 ㎍ /gDW であった．また果実重と辛味成分含量の間に負の相関が認められた．C. baccatum の辛味は低〜中程度であるが，非辛味系統はほとんど認められず，唯一1 系統（‘Kaleidoscope’）が非辛味であった．この非辛味の安定性を調査するために，辛味程度の異なる系統とともに異なる収穫時期におけるカプサイシノイド含量を調査した． 　他のC. baccatum 系統ではカプサイシノイド含量は収穫時期で変化したが，‘Kaleidoscope’ ではいずれの収穫時期でもカプサイシノイドは検出されなかった．本研究で見出された非辛味系統は将来のC. baccatum の育種において有用であろう