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Determining the driving climatic factors at critical periods and potential legacy effects is crucial for grassland productivity predictions on the Qinghai–Tibet Plateau (QTP). However, studies with limited and ex situ ground samples from highly heterogeneous alpine meadows brought great uncertainties. This study determined the key climatic factors at critical plant developmental stages and the impact of previous plant growth status for interannual aboveground net primary productivity (ANPP) variations in different QTP grassland types. We hypothesize that the impact of climatic factors on grassland productivity varies in different periods and different vegetation types, while its legacy effects are not great. Pixel-based partial least squares regression was used to associate interannual ANPP with precipitation and air temperature at different developmental stages and prior-year ANPP from 2000 to 2019 using remote sensing techniques. Results indicated different findings from previous studies. Precipitation at the reproductive stage (July–August) was the most prominent controlling factor for ANPP which was also significantly affected by precipitation and temperature at the withering (September–October) and dormant stage (November–February), respectively. The influence of precipitation was more significant in alpine meadows than in alpine steppes, while the differentiated responses to climatic factors were attributed to differences in water consumption at different developmental stages induced by leaf area changes, bud sprouting, growth, and protection from frost damage. The prior-year ANPP showed a non-significant impact on ANPP of current year, except for alpine steppes, and this impact was much less than that of current-year climatic factors, which may be attributed to the reduced annual ANPP variations related to the inter-annual carbon circulation of alpine perennial herbaceous plants and diverse root/shoot ratios in different vegetation types. These findings can assist in improving the interannual ANPP predictions on the QTP under global climate change.

The product. Coconut water (Cocos nucifera L.) is an ancien t tropical beverage whose popularity on the international market has been continuously increasing in recent years. Uses. Besides its various traditional uses, this refreshing liqu id extracted from the coconut fruit has recently been described as a “sport beverage” and has drawn the attention of manufacturers as a natural functional drink. Composition. Coconut water has a low matter content (2% to 5% wet basis), mainly comprising sugars and minerals. Quality criteria, such as the water per nut ratio, Total Soluble Solids (TSS), total sugar per nut, and [reducing sugars / total sugars] ratio, are good indicators for estimating the suitability of coconut cultivars for the production of coconut water. Regarding these criteria, dwarf varieties are the most suitable cultivars to obtain a tasty product. Properties. The quality of coconut water can not only be attributed to sugars and minerals because it also has a typical flavour and some original properties. Although many authors have cited medicinal uses or growth-promoting activities, only a few publications have clearly identified the components responsible for these properties. Discussion. Results of former and recent investigations are discussed. Finally, suggestions are made for further research to increase our knowledge of this original tropical juice. Le produit. L’eau de coco (Cocos nucifera L.) est un ancien breuvage dont la popularité est grandissante sur le marché international des boissons. Usages. Au-delà de ses usages traditionnels, ce liquide rafraîchissant extrait de la noix a été décrit comme une « boisson de réhydratation pour sportif ». Des industriels ont ainsi mis en exergue ses propriétés fonctionnelles naturelles. Composition. L’eau de coco a une faible teneur en matière sèche (2 % à 5 % en base humide), constituée de sucres et minéraux. Des critères comme le poids de l’eau par noix, les solides solubles totaux, la quantité de sucres totaux par noix, le rapport [sucres réducteurs / sucres totaux] sont de bons indicateurs pour sélectionner les cultivars adaptés à la production d’eau de coco. Au regard de ces critères, les variétés naines sont souvent les mieux adaptées à la production de cette boisson. Propriétés. La qualité de l’eau de coco est aussi liée à une flaveur typique et recherchée ainsi qu’à certaines propriétés spécifiques. Bien que plusieurs auteurs aient attribué à l’eau de coco des propriétés médicinales et aient prouvé son effet positif sur la croissance des cellules, peu de publications identifient clairement les molécules responsables de ces actions. Discussion. Pour la première fois, les recherches sur l’eau de coco, des plus anciennes au plus récentes, sont synthétisées et conduisent à proposer des pistes pour améliorer notre connaissance de ce jus de fruit tropical atypique. El producto. El agua de coco (Cocos nucifera L.) es una antigua bebida, cuya popularidad es cada vez mayor en el mercado multinacional de los refrescos. Usos. Más allá de su uso tradicional, este jugo refrescante extraído del coco se describió como una « bebida rehidratante para los deportistas ». De ahí que la industria resaltara las propiedades funcionales naturales de este fruto. Composición. El agua de coco posee un bajo contenido de materia seca (2 % a 5 % en base húmeda), compuesta, a su vez, por azúcares y minerales. Para seleccionar los cultivares adaptados a la producción de agua de coco, algunos de los siguientes criterios son muy buenos: el peso del agua por fruto, los sólidos totales solubles, la cantidad de azúcares totales por fruto, la relación [azúcares reductores / azúcares totales]. Habida cuenta de dichos criterios, con frecuencia, las variedades enanas son las que mejor se adaptan a la producción de este refresco. Propiedades. Asimismo, la calidad del agua de coco está relacionada a un sabor típico e intenso y a ciertas propiedades específicas. A pesar de que numerosos autores hayan atribuido al agua de coco unas propiedades medicinales y hayan demostrado su efecto positivo en el crecimiento de las células, aún existen pocas publicaciones que identifiquen claramente las moléculas responsables de dichas acciones. Discusión. Por primera vez, están recopiladas todas las investigaciones sobre el agua de coco, desde las más antiguas hasta las más recientes, y proponen nuevas pistas para mejorar nuestro conocimiento sobre este original zumo de fruta tropical.

Wheat is a staple crop that suffers from massive yield losses caused by cereal aphids. Many factors can determine the abundance of cereal aphids and the damage they cause to plants; among them are the plant's genetic background, as well as environmental conditions such as spatial position within the plot, the composition and the distance from neighboring vegetation. Although the effects of these factors have been under scrutiny for many years, the combined effect of both factors on aphid populations is not fully understood. The goal of this study was to examine the collective impact of genotype and environment on wheat phenology (developmental stages), chemical diversity (metabolites), and insect susceptibility, as manifested by cereal aphid abundance. To determine the influence of plant genotype on the metrics mentioned above, we measured the phenology, chemical profile, and aphid abundance of four wheat genotypes, including the tetraploid wild emmer ( ssp. dicoccoides cv. Zavitan), tetraploid durum ( ssp. durum cv. Svevo), and two hexaploid spring bread ( ), 'Rotem' and 'Chinese Spring'. These genotypes are referred to as \"focal\" plants. To evaluate the impact of the environment, we scored the distance of each focal plant (spatial position) from two neighboring vegetation types: (i) natural resource and (ii) monoculture wheat resource. The results demonstrated that the wild emmer wheat was the most aphid-resistant, while the bread wheat Rotem was most aphid-susceptible. Aphids were more abundant in plants that matured early. The spatial position analysis demonstrated that aphids were more abundant in focal plants located closer to the margin monoculture wheat resource rather than to the natural resource, suggesting a resource concentration effect. The analysis of metabolic diversity showed that the levels of three specialized metabolites from the flavonoid class, differed between the wheat genotypes and some minor changes in central metabolites were shown as well. Altogether, these results demonstrate a combined effect of genetic background and spatial position on wheat phenology and aphid abundance on plants. This exposes the potential role of the marginal vegetation environment in shaping the insect population of desirable crops. These findings highlight the importance of maintaining plant intra-specific variation in the agriculture system because of its potential applications in reducing pest density.

Abstract The olive tree is a hallmark crop in the Mediterranean region. Its cultivation is characterized by an enormous variability in existing genotypes and geographical areas. As regards the associated microbial communities of the olive tree, despite progress, we still lack comprehensive knowledge in the description of these key determinants of plant health and productivity. Here, we determined the prokaryotic, fungal and arbuscular mycorrhizal fungal (AMF) microbiome in below- (rhizospheric soil, roots) and above-ground (phyllosphere and carposphere) plant compartments of two olive varieties ‘Koroneiki’ and ‘Chondrolia Chalkidikis’ grown in Southern and Northern Greece respectively, in five developmental stages along a full fruit-bearing season. Distinct microbial communities were supported in above- and below-ground plant parts; while the former tended to be similar between the two varieties/locations, the latter were location specific. In both varieties/locations, a seasonally stable root microbiome was observed over time; in contrast the plant microbiome in the other compartments were prone to changes over time, which may be related to seasonal environmental change and/or to plant developmental stage. We noted that olive roots exhibited an AMF-specific filtering effect (not observed for bacteria and general fungi) onto the rhizosphere AMF communities of the two olive varieties/locations/, leading to the assemblage of homogenous intraradical AMF communities. Finally, shared microbiome members between the two olive varieties/locations include bacterial and fungal taxa with putative functional attributes that may contribute to olive tree tolerance to abiotic and biotic stress.

A rapid Agrobacterium tumefaciens-mediated transformation system for wheat was developed using freshly isolated immature embryos, precultured immature embryos, and embryogenic calli as explants. The explants were inoculated with a disarmed A. tumefaciens strain C58 (ABI) harboring the binary vector pMON18365 containing the beta-glucuronidase gene with an intron, and a selectable marker, the neomycin phosphotransferase II gene. Various factors were found to influence the transfer-DNA delivery efficiency, such as explant tissue and surfactants present in the inoculation medium. The inoculated immature embryos or embryogenic calli were selected on G418-containing media. Transgenic plants were regenerated from all three types of explants. The total time required from inoculation to the establishment of plants in soil was 2.5 to 3 months. So far, more than 100 transgenic events have been produced. Almost all transformants were morphologically normal. Stable integration, expression, and inheritance of the transgenes were confirmed by molecular and genetic analysis. One to five copies of the transgene were integrated into the wheat genome without rearrangement. Approximately 35% of the transgenic plants received a single copy of the transgenes based on Southern analysis of 26 events. Transgenes in T1 progeny segregated in a Mendelian fashion in most of the transgenic plants

Plants, unlike other higher eukaryotes, possess all the necessary enzymatic equipment for de novo synthesis of methionine, an amino acid that supports additional roles than simply serving as a building block for protein synthesis. This is because methionine is the immediate precursor of S-adenosylmethionine (AdoMet), which plays numerous roles of being the major methyl-group donor in transmethylation reactions and an intermediate in the biosynthesis of polyamines and of the phytohormone ethylene. In addition, AdoMet has regulatory function in plants behaving as an allosteric activator of threonine synthase. Among the AdoMet-dependent reactions occurring in plants, methylation of cytosine residues in DNA has raised recent interest because impediment of this function alters plant morphology and induces homeotic alterations in flower organs. Also, AdoMet metabolism seems somehow implicated in plant growth via an as yet fully understood link with plant-growth hormones such as cytokinins and auxin and in plant pathogen interactions. Because of this central role in cellular metabolism, a precise knowledge of the biosynthetic pathways that are responsible for homeostatic regulation of methionine and AdoMet in plants has practical implications, particularly in herbicide design

Estimates of inbreeding depression obtained from the literature were used to evaluate the association between inbreeding depression and the degree of self-fertilization in natural plant populations. Theoretical models predict that the magnitude of inbreeding depression will decrease with inbreeding as deleterious recessive alleles are expressed and purged through selection. If selection acts differentially among life history stages and deleterious effects are uncorrelated among stages, then the timing of inbreeding depression may also evolve with inbreeding. Estimates of cumulative inbreeding depression and stage-specific inbreeding depression (four stages: seed production of parent, germination, juvenile survival, and growth/reproduction) were compiled for 79 populations (using means of replicates, N = 62) comprising 54 species from 23 families of vascular plants. Where available, data on the mating system also were collected and used as a measure of inbreeding history A significant negative correlation was found between cumulative inbreeding depression and the primary selfing rate for the combined sample of angiosperms (N = 35) and gymnosperms (N = 9); the correlation was significant for angiosperms but not gymnosperms examined separately The average inbreeding depression in predominantly selfing species (δ = 0.23) was significantly less (43%) than that in predominantly outcrossing species (δ = 0.53). These results support the theoretical prediction that selfing reduces the magnitude of inbreeding depression. Most self-fertilizing species expressed the majority of their inbreeding depression late in the life cycle, at the stage of growth/reproduction (14 of 18 species), whereas outcrossing species expressed much of their inbreeding depression either early, at seed production (17 of 40 species), or late (19 species). For species with four life stages examined, selfing and outcrossing species differed in the magnitude of inbreeding depression at the stage of seed production (selfing δ = 0.05, N = 11, outcrossing δ = 0.32, N = 31), germination (selfing δ = 0.02, outcrossing δ = 0.12), and survival to reproduction (selfing δ = 0.04, outcrossing δ = 0.15), but not at growth and reproduction (selfing δ = 0.21, outcrossing δ = 0.27); inbreeding depression in selfers relative to outcrossers increased from early to late life stages. These results support the hypothesis that most early acting inbreeding depression is due to recessive lethals and can be purged through inbreeding, whereas much of the late-acting inbreeding depression is due to weakly deleterious mutations and is very difficult to purge, even under extreme inbreeding.

Cell death in higher plants has been widely observed in predictable patterns throughout development and in response to pathogenic infection. Genetic, biochemical, and morphological evidence suggests that these cell deaths occur as active processes and can be defined formally as examples of programmed cell death (PCD). Intriguingly, plants have at least two types of PCD, an observation that is also true of PCD in animals [Schwartz, L.M., Smith, W.W., Jones, M.E.E. and Osborne, B.A. (1993) Proc. Natl. Acad. Sci. USA 90, 980-984]. Thus, in plants, PCD resembles either a common form of PCD seen in animals called apoptosis or it resembles a morphologically distinct form of cell death. The ubiquitous occurrence and necessity of PCD for plant development and defense suggest that the underlying mechanisms of regulation and execution of these processes merit further examination.