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The contribution of spike photosynthesis to grain yield (GY) has been overlooked in the accurate spectral prediction of yield. Thus, it’s essential to construct and estimate a yield-related phenotypic trait considering spike photosynthesis. Based on field and spectral reflectance data from 19 wheat cultivars under two nitrogen fertilization conditions in two years, our objectives were to (i) construct a yield-related phenotypic trait (spike–leaf composite indicator, SLI) accounting for the contribution of the spike to photosynthesis, (ii) develop a novel spectral index (enhanced triangle vegetation index, ETVI3) sensitive to SLI, and (iii) establish and evaluate SLI estimation models by integrating spectral indices and machine learning algorithms. The results showed that SLI was sensitive to nitrogen fertilizer and wheat cultivar variation as well as a better predictor of yield than the leaf area index. ETVI3 maintained a strong correlation with SLI throughout the growth stage, whereas the correlations of other spectral indices with SLI were poor after spike emergence. Integrating spectral indices and machine learning algorithms improved the estimation accuracy of SLI, with the most accurate estimates of SLI showing coefficient of determination, root mean square error (RMSE), and relative RMSE values of 0.71, 0.047, and 26.93%, respectively. These results provide new insights into the role of fruiting organs for the accurate spectral prediction of GY. This high-throughput SLI estimation approach can be applied for wheat yield prediction at whole growth stages and may be assisted with agronomical practices and variety selection. [ABSTRACT FROM AUTHOR]

The need for consumption of mustard plant (Brassica juncea L.) has increased every year. One of the efforts to increase its production and quality by applications of inorganic and organic fertilizer. This study aimed to evaluate the productivity of mustard plants treated with liquid organic fertilizer, a byproduct of black soldier fly (BSF), and inorganic fertilizer (NPK). Mustard plants were grown at Karanggayam Research Station, Caturtunggal, Depok, Sleman, Yogyakarta were treated with water as a control, NPK fertilizer, DoctoRS organic fertilizer at 0.05%, organic fertilizer A, and B at 0.1, 0.15, 0.20, and 0.25%. The effects of treatments to the phenotypic and the chlorophyll of the mustards were done after 2 weeks of treatments. The results showed that there were significant different on the stem height, number of leaves, leaf width, leaf length, and wet weight. These were in line with the total chlorophyll. Liquid organic fertilizer content analysis showed that DoctoRS liquid organic fertilizer and liquid organic fertilizer A were the most in accordance with the national standards for organic fertilizers on the parameters of pH, Mg, Ca, and TPC. [ABSTRACT FROM AUTHOR]

Background: Plasticity in response to environmental drivers can help trees cope with droughts. However, our understanding of the importance of plasticity and physiological adjustments in trees under global change is limited. Methods: We used the International Tree-Ring Data Bank (ITRDB) to examine 20th century growth responses in conifer trees during (resistance) and following (resilience) years of severe soil and atmospheric droughts occurring in isolation or as compound events. Growth resilience indices were calculated using observed growth divided by expected growth to avoid spurious correlations, in which the expected values were obtained by the autoregressive moving average (ARIMA) model. We used high atmospheric vapour pressure deficit (VPD) to select years of atmospheric drought and low annual values of the Standardized Precipitation-Evapotranspiration Index (SPEI) to select years with soil drought. We acquired the sensitivities (i.e., the slopes of the relationships) by fitting the resilience indices as a function of environmental drivers, and assessed how these sensitivities changed over time for different types of drought events using linear mixed models. We also checked whether plasticity in growth responses was sufficient to prevent long-term trends of growth reductions during or after severe droughts. We acknowledge that by focusing on the response of surviving trees from the ITRDB we are potentially biasing our results towards higher resilience, as stand level responses (e.g., mortality) may result in lowered competition after the disturbance event. Results: Sensitivities of resilience to VPD and SPEI changed throughout the 20th century, with the directions of these changes often reversing in the second half of the century. For the 1961-2010 period, changing sensitivities had positive effects on resilience, especially following years of high-VPD and compound events, avoiding growth losses that would have occurred if sensitivities had remained constant. Despite sensitivity changes, resilience was still lower at the end of the 20th century compared to the beginning of the century. Conclusions: Future adjustments to low-SPEI and high-VPD events are likely to continue to compensate for the trends in climate only partially, leading to further generalized reductions in tree growth of conifers. An improved understanding of these plastic adjustments and their limits, as well as potential compensatory processes at the stand level, is needed to project forest responses to climate change. [ABSTRACT FROM AUTHOR]

Plant roots exhibit plasticity in their branching patterns to forage efficiently for heterogeneously distributed resources, such as soil water. The xerobranching response represses lateral root formation when roots lose contact with water. Here, we show that xerobranching is regulated by radial movement of the phloem-derived hormone abscisic acid, which disrupts intercellular communication between inner and outer cell layers through plasmodesmata. Closure of these intercellular pores disrupts the inward movement of the hormone signal auxin, blocking lateral root branching. Once root tips regain contact with moisture, the abscisic acid response rapidly attenuates. Our study reveals how roots adapt their branching pattern to heterogeneous soil water conditions by linking changes in hydraulic flux with dynamic hormone redistribution. [ABSTRACT FROM AUTHOR]

Aflatoxinproduced by the fungus Aspergillus flavus (Link:Fr) can accumulate in maize (Zea mays L.) and poses serious human health and economic concerns, especially in sub‐Saharan Africa. Genetic resistance against A. flavus infection and spread, and subsequent production of aflatoxin, is a key tool for reducing the problem. Some resistant inbred donor lines carry quantitative trait loci (QTL) for resistance that have a sufficiently large phenotypic effect to be used for marker assisted introgression. New sources of resistance, unrelated to previously characterized resistant lines, could carry unique QTL with large phenotypic effect on resistance to complement the previously identified QTL. To this end, CML69, derived from Caribbean Composite germplasm unrelated to previously released resistant lines, was used in QTL mapping to identify and characterize new resistance QTL. Seventeen QTL were identified, although some may be the same genetic region causing QTL identified in more than one environment, indicating that these QTL are stably expressed across environments. These QTL explained 1.8–12.6% each and jointly up to 55% of the phenotypic variation. The largest effect QTL, in particular the QTL in bin 4.08, are most likely the same as has been reported in QTL mapping studies of other resistant maize lines, suggesting both environmental and genetic stability. This stability will be very useful when these QTL are used in maize improvement programs, and single nucleotide polymorphism (SNP) markers linked to these QTL were identified to facilitate this use. CML69, and other lines related to it by pedigree, may make good parents for new aflatoxin resistant hybrids. Core Ideas: QTL for resistance to aflatoxin accumulation were identified in maize inbred line CML69.These QTL explained 1.8–12.6% each and jointly up to 55% of the phenotypic variation.We discuss how best to use the resistance from CML69 in a practical breeding program. [ABSTRACT FROM AUTHOR]

The regulation of resource allocation in biological systems observed today is the cumulative result of natural selection in ancestral and recent environments. To what extent are observed resource allocation patterns in different photosynthetic types optimally adapted to current conditions, and to what extent do they reflect ancestral environments? Here, we explore these questions for C3, C4, and C3–C4 intermediate plants of the model genus Flaveria. We developed a detailed mathematical model of carbon fixation, which accounts for various environmental parameters and for energy and nitrogen partitioning across photosynthetic components. This allows us to assess environment-dependent plant physiology and performance as a function of resource allocation patterns. Models of C4 plants optimized for conditions experienced by evolutionary ancestors perform better than models accounting for experimental growth conditions, indicating low phenotypic plasticity. Supporting this interpretation, the model predicts that C4 species need to re-allocate more nitrogen between photosynthetic components than C3 species to adapt to new environments. We thus hypothesize that observed resource distribution patterns in C4 plants still reflect optimality in ancestral environments, allowing the quantitative inference of these environments from today's plants. Our work allows us to quantify environmental effects on photosynthetic resource allocation and performance in the light of evolutionary history. [ABSTRACT FROM AUTHOR]

Copyright of Revista Colombiana de Ciencias Hortícolas is the property of Revista Colombiana de Ciencias Horticolas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The fatty acid compositions, polymorphism, solid fat content (SFC), thermal properties, microstructure and rheological properties of fat blends of rice bran wax and corn oil (RWC) with low-melting-point fractions of cocoa butter (LFCB) in the range of 20-50% were investigated. With the raising content of LFCB, the hardness, SFC, storage modulus (G′) and loss modulus (G′′) of blend samples increased. The unsaturated fatty acids of blend samples with different LFCB proportion were in the range of 60.42% to 71.25%. Two kinds of polymorphism were observed in blend samples, which were β′-Form and β-Form. During the crystallization process, the rice bran wax was first crystallized, and then induced a part of LFCB formed β′-Form crystals and another LFCB formed the β-Form crystals. The results show that the addition of LFCB could improve the plasticity of fat blends and reduce the difference in properties between them and commercial shortening. [ABSTRACT FROM AUTHOR]

Plant phenotypic plasticity describes altered phenotypic performance of an individual when grown in different environments. Exploring genetic architecture underlying plant plasticity variation may help mitigate the detrimental effects of a rapidly changing climate on agriculture, but little research has been done in this area to date. In the present study, we established a population of 976 maize F1 hybrids by crossing 488 diverse inbred lines with two elite testers. Genome-wide association study identified hundreds of quantitative trait loci associated with phenotypic plasticity variation across diverse F1 hybrids, the majority of which contributed very little variance, in accordance with the polygenic nature of these traits. We identified several quantitative trait locus regions that may have been selected during the tropical-temperate adaptation process. We also observed heterosis in terms of phenotypic plasticity, in addition to the traditional genetic value differences measured between hybrid and inbred lines, and the pattern of which was affected by genetic background. Our results demonstrate a landscape of phenotypic plasticity in maize, which will aid in the understanding of its genetic architecture, its contribution to adaptation and heterosis, and how it may be exploited for future maize breeding in a rapidly changing environment. [ABSTRACT FROM AUTHOR]

In this study, four pure lines of maize (ZM19R, ZM7R, HS, ZM5) were used, which took the symbols from L1, L2, L3 and L4 sequentially and four concentrations of chemical mutagen sodium azide are (0, 40µm, 50µm, 60µm) as well as took symbols (M0, M1, M2, M3), Soak the seeds in concentrations from the chemical mutagen for 6 hours, Grains were planted in the field according to the Randomized complete Block design (RCBD) using the Factorial system of experiments in the form of experimental units, which included three replicates, each replicate contains 16 experimental units of 2m × 3m. The experimental units were planted by 4 lines for each experimental unit the distance between one line and another 0.75m and the distance between the plants 0.25m. The fertilization process was carried add urea fertilizer with a concentration of (46%)N rate of 300 kg /h in two add during the first cultivation with the amount of phosphate fertilizer P2O5 rate of 200 kg/h. As for the second add of urea fertilizer was added before the tussling. The hoeing and weeding process was conducted to control the and when the plants reached full maturity; random samples were taken from the plants in the field (5) plants from each experimental unit. To study the effect of NaN3 sodium azide on some quantitative traits, which are silking, plant height, length ear, leaf area, number of ears, grain weight, grain yield. The results showed that there were statistically significant differences for all studied trait except for the trait of silking in the mutagens. The highest average for a 300-grain weight showed in the third line(L3) was 73.33 g, while the highest average of the mutagen was a concentration of Mm50 of 77.25g and the highest mean fore interaction of the third Line with a concentration of 50Mm was 78.33 g. Statistical and genetic analyzes were performed to estimate both the genetic parameters that represent the inheritance in the broad sense (H2 b.s%) and the phenotypic coefficient variation (PCV)%) and the genetic coefficient variation (% GCV) and the expected genetic improvement of the trait. As well as statistical parameters were estimated, including variance, standard deviation, Arithmetic average, and standard error for each of the studied traits. Statistical analyzes showed the effect of the variance in their values on the traits of the yield and its components. The value of the coefficient of variance (%C.V)in the trait yield was 6.80%, while the weight of the grain decreased and recorded 0.23%. While, the variance recorded its highest value in the trait of the yield was 95.4, and this value decreased in the two trait of the number of ears and the weight of the grain (0.0097 and 0.028), respectively. The highest value of genetic improvement in the traits number of ears plants reached (80.47) through study factors due to the occurrence of genetic variations of the mutant lines by effect sodium azide. [ABSTRACT FROM AUTHOR]

Seventy two gram negative bacterial isolates were isolated from ninety eight burn wounds specimens obtained from Baghdad hospitals after culturing on macConkey agar medium. Fourty seven (47.9%) out of them were identified as Pseudomonas aeruginosa after culturing on ceramide agar medium and performing further biochemical tests, all these bacterial isolates were identified by VITEK2 compact system. They were individually screened for pyocyanin production by using mineral salt broth supplemented with 1% peptone, the results showed that nine bacterial isolates were pyocyanin producers and the isolate P. aeruginosa (Pa15) was the strongest in pyocyanin production. All 47 isolates went through the antibiotic susceptibility test, the results showed that 85.1% of total isolates were sensitive to imipenem and 60% were resistant to ceftazidime, while for the nine pyocyanin producers isolates, the results showed that 75% of isolates were sensitive to gentamicin while 88% were resistant to ciprofloxacin, levofloxacin and ceftazidime. Nine isolates which were resistant and gave the highest pyocyanin production were selected for this study. Then, the isolates were tested to determine the minimal inhibitory concentration for ciprofloxacin against P. aeruginosa, by agar dilution method, the results showed that the MIC distributed between 8 and 128 µg/ml. The strongest isolate in pyocyanin production P. aeruginosa (Pa15) was tested to determine the minimal inhibitory concentration for sliver nanoparticles against it, the minimal inhibitory concentration was 0.012 mg/ml. The control with three treatments, the sub MIC (0.006 and 0.003 mg/ml) for sliver nanoparticles and the sub MIC 6 mg/ml for ciprofloxacin against P. aeruginosa (Pa15) were taken to study pyocyanin expression. DNA of P. aeruginosa (Pa15) was successfully extracted from overnight cultures, and PCR was conducted for P. aeruginosa (Pa15) to amplify the constitutional genes 16srRNA, phzM and phzS and the bands were confirmed with gel electrophoresis, the results showed that genes 16srRNA (965 bp) and phzM (312 bp) were detected. RNA was extracted from the selected isolate after growing on cetrimide agar medium as control in addition to three treatments, the sub MIC of silver nanoparticle (0.006 mg/ml and 0.003 mg/ml) and sub MIC of ciprofloxacin antibiotic (6mg /ml), The results of QRT-PCR in this study showed that the expression of phzM gene in the presence of silver nanoparticles was decreased to 0.895025 fold compared to the control sample, But, exposure to ciprofloxacin antibiotic increased the expression of phzM gene by two folds. [ABSTRACT FROM AUTHOR]

Aims Clonal growth is associated with invasiveness in introduced plant species, but few studies have compared invasive and noninvasive introduced clonal species to investigate which clonal traits may underlie invasiveness. To test the hypothesis that greater capacity to increase clonal growth via physiological integration of connected ramets increases invasiveness in clonal plants, we compared the effects of severing connections on accumulation of mass in the two species of the creeping, succulent, perennial, herbaceous genus Carpobrotus that have been introduced on sand dunes along the Pacific Coast of northern California, the highly invasive species Carpobrotus edulis and the co-occurring, noninvasive species Carpobrotus chilensis. Methods Pairs of ramets from four mixed populations of the species from California were grown in a common garden for 3 months with and without severing the stem connecting the ramets. To simulate the effect of clones on soils in natural populations, the older ramet was grown in sand amended with potting compost and the younger in sand alone. Important Findings Severance decreased net growth in mass by ~60% in C. edulis and ~100% in C. chilensis , due mainly to the negative effect of severance on the shoot mass of the younger ramet within a pair. Contrary to the hypothesis, this suggests that physiological integration increases growth more in the less invasive species. However, severance also decreased allocation of mass to roots in the older ramet and increased it in the younger ramet in a pair, and the effect on the younger ramet was about twice as great in C. edulis as in C. chilensis. This indicates that the more invasive species shows greater phenotypic plasticity in response to physiological integration, in particular greater capacity for division of labor. This could contribute to greater long-term growth and suggests that the division of labor may be a trait that underlies the association between clonal growth and invasiveness in plants. [ABSTRACT FROM AUTHOR]

Floral morphology and pigmentation are both charismatic and economically relevant traits associated with cultivated sunflower (Helianthus annuus L.). Recent work has linked floral morphology and pigmentation to pollinator efficiency and seed yield. Understanding the genetic architecture of such traits is essential for crop improvement, and gives insight into the role of genetic constraints in shaping floral diversity. A diversity panel of 288 sunflower genotypes was phenotyped for a variety of morphological, phenological, and color traits in both a greenhouse and a field setting. Association mapping was performed using 5788 SNP markers using a mixed linear model approach. Several dozen markers across 10 linkage groups were significantly associated with variation in morphological and color trait variation. Substantial trait plasticity was observed between greenhouse and field phenotyping, and associations differed between environments. Color traits mapped more strongly than morphology in both settings, with markers together explaining 16% of petal carotenoid content in the greenhouse, and 17% and 24% of variation in disc anthocyanin presence in the field and greenhouse, respectively. Morphological traits like disc size mapped more strongly in the field, with markers together explaining up to 19% of disc size variation. Loci identified here through association mapping within cultivated germplasm differ from those identified through biparental crosses between modern cultivated sunflower and either its wild progenitor or domesticated landraces. Several loci lie within genomic regions involved in domestication. Differences between phenotype expression under greenhouse and field conditions highlight the importance of plasticity in determining floral morphology and pigmentation. [ABSTRACT FROM AUTHOR]

This study evaluated the effect of three N fertilization levels 60 (low), 120 (medium), and 180 (high) kg N ha−1 and soil moisture content gradients created by a line-source sprinkler on the expression of plasticity in lateral root branching and dry matter production (DMP) of upland new rice for Africa (NERICA) 1 and 4. There were no significant differences in DMP between NERICA 1 and 4 under well-watered, mild drought, and severe drought conditions regardless of N level. In contrast, under moderate drought (12–21% v/v of soil moisture content [SMC] in 2011 and 16–24% v/v of SMC in 2012), NERICA 1 had significantly higher shoot dry weight, total root length (TRL), lateral root length, and branching index than NERICA 4 at medium and high N; however, there was no significant difference between the two NERICAs in DMP at low N. TRL of NERICA 1 was significantly higher under moderate drought than well-watered conditions, but only with medium and high N. Regardless of N level, moderate drought did not enhance NERICA 4's root system. Thus, NERICA 1's root system exhibited plastic development, promoting lateral root branching at medium and high N. These morphological changes were associated with the greater DMP in NERICA 1 than NERICA 4 under moderate drought, whereas the lack of such plasticity at low N meant genotypic differences in DMP were obscured. Our findings implied that N application can improve upland NERICA productivity under moderate drought conditions, but differences in variety and field conditions may influence efficacy. [ABSTRACT FROM AUTHOR]

Recognition and exploitation of hybrid vigor or heterosis among individual crosses of plants and animals has a long and distinguished history. Its manifestation is influenced by a combination of genetic, epigenetic, phenotypic, and environmental factors. Although heterosis is known to be governed by both dominant and epistatic gene action, its expression is greatly influenced by nonlinear interaction among epigenetic and phenotypic (phenomic) components. The magnitude of heterosis is generally inferred post hoc by the phenotypic performance of hybrids among laboriously made individual crosses. The expression of dominance, however, is nonlinear at the cellular level and obeys the principles underlying metabolic flux. Then, is it possible to exploit these relationships to predict heterosis? Vasseur and colleagues have indeed demonstrated the feasibility of such an approach in a series of experiments taking integrated biochemical and computational approaches, as well as testing these results on large samples of model organisms. The results offer promise toward phenomic prediction of heterosis across a wide array of organisms. [ABSTRACT FROM AUTHOR]

Heterosis describes the phenotypic superiority of hybrids over their parents in traits related to agronomic performance and fitness. Understanding and predicting nonadditive inheritance such as heterosis is crucial for evolutionary biology as well as for plant and animal breeding. However, the physiological bases of heterosis remain debated. Moreover, empirical data in various species have shown that diverse genetic and molecular mechanisms are likely to explain heterosis, making it difficult to predict its emergence and amplitude from parental genotypes alone. In this study, we examined a model of physiological dominance initially proposed by Sewall Wright to explain the nonadditive inheritance of traits like metabolic fluxes at the cellular level. We evaluated Wright's model for two fitness-related traits at the whole-plant level, growth rate and fruit number, using 450 hybrids derived from crosses among natural accessions of A. thaliana. We found that allometric relationships between traits constrain phenotypic variation in a nonlinear and similar manner in hybrids and accessions. These allometric relationships behave predictably, explaining up to 75% of heterosis amplitude, while genetic distance among parents at best explains 7%. Thus, our findings are consistent with Wright's model of physiological dominance and suggest that the emergence of heterosis on plant performance is an intrinsic property of nonlinear relationships between traits. Furthermore, our study highlights the potential of a geometric approach of phenotypic relationships for predicting heterosis of major components of crop productivity and yield. [ABSTRACT FROM AUTHOR]

Background and Aims Depending on the species, water stress affects different growth and developmental processes, mainly due to changes in hydraulic properties and hormonal signalling. This study compared the impact of water stress on tree development and organ growth in three apple cultivars. Methods Trees were differentially irrigated to induce water stress or to provide well-watered conditions in their second and third years of growth. Effects of water stress were evaluated at tree scale by shoot number and proportions of the different types of shoots, and at shoot scale by metamer appearance rate, growth duration and arrest time, as well as organ size. Key Results Water stress promoted early growth cessation, prolonged summer arrests and decreased growth resumptions, thus modifying within-tree shoot demography in favour of short shoots. Growth cessations occurred in mild water stress conditions before any difference in stem water potential appeared. No major impact was observed on organ size. Consistently with tree ontogeny, the number of shoots that resumed growth after summer arrest decreased with years, but more in water-stressed than well-watered conditions. Conclusions Even though the impact of water stress differed slightly among cultivars, the reduction in neoformation and increase in summer arrest played a common role in apple tree morphological responses and led to stress avoidance by early reduction of tree leaf area. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ecological stability and plasticity of maize hybrids in different groups of ripeness - Knezha 307, Knezha 435, Knezha 509 and Knezha M625 by the traits grain yield and length of the ear was evaluated. The ecological parameters were determined by using the method of Eberhart and Russell (1966) and of Pakudin and Lopatina (1984). In the period of study (2014-2017) the hybrids demonstrate different plasticity and stability by the examined traits. The results of the analysis of the variances demonstrate reliable differences of the hybrids and the conditions for the two traits and primarily reliable interaction genotype - environment. The variances of the regression Si2 of all hybrids for the trait grain yield reliably differ from their theoretical value which determines them as plastic, i.e. responsive to more favourable conditions of growth. According to the values of bi the hybrid Knezha 435 (bi<1) is stable by the trait grain yield, the hybrids Knezha 307 and Knezha M625 are with values of bi close to one and have relatively medium stability and Knezha 509 with bi>1 is unstable. With reliable values of Si2 for the trait length of the ear is only the hybrid Knezha M625. The ecological stability of the other hybrids was evaluated by the value of the coefficient of regression (bi). Increased stability by this trait is demonstrated by Knezha 435, followed by Knezha 509. Knezha 307 is with medium stability (bi=1.1) by the respective trait. [ABSTRACT FROM AUTHOR]

Understanding intraspecific variation in the vulnerability of the xylem to hydraulic failure during drought is critical in predicting the response of forest tree species to climate change. However, few studies have assessed intraspecific variation in this trait, and a likely limitation is the large number of measurements required to generate the standard 'vulnerability curve' used to assess hydraulic failure. Here we explore an alternative approach that requires fewer measurements, and assess within species variation in leaf xylem vulnerability in Eucalyptus globulus Labill., an ecologically and economically important species with known genetic variation in drought tolerance. Using this approach we demonstrate significant phenotypic differences and evidence of plasticity among two provenances with contrasting drought tolerance. Few studies assess the range in drought tolerance that exists among individuals of the same species, yet this is critical in accurately predicting the effect of climate change on plants. This may be the result of the labour intensive process of assessing drought tolerance, which typically requires multiple measurements per individual. Here we present an alternative approach for large-scale analysis that reduces the number of measurements, thereby improving efficiency and increasing our ability to assess a broader range of individuals. [ABSTRACT FROM AUTHOR]

Highlights • At the Lake Garda, Cistus albidus is in conditions of extreme range marginality. • Here, it shows a high adaptive potential due to genetic and ecological factors. • It has a high phenotypic plasticity and good levels of genetic variation. • Phenological response is much higher than what is known for the Mediterranean species. • Bayesian analysis does not support any genetic structuring of the population. Abstract The potential effects of climate change on the distribution of Mediterranean plants at their peripheral range make them extremely vulnerable to environmental fluctuations. The northern-most Italian population of Cistus albidus provides an outstanding case for study, as it grows at the extreme northern edge of its range and because phenological data have been available since the early XIX century. In the period 2012–2017, we analysed the population demography and spatial structure, growth and flowering phenology, and genetic variability to understand the history, current state and possible evolution of this population. Lastly, the population data were tested for association with environmental factors. The population studied consists of plants on average 10 years old, showing the highest growth rates in spring and autumn. Anthesis starts in April and ends in early June and is significantly dependent on temperature. High levels of genetic variability are present (average H e = 0.471), with heterozygote excess detected at four loci out of five. Bayesian analysis does not support any genetic structuring of the population. The aggregated pattern in the distribution of individuals and their phenological traits, together with the absence of genetic structuring, seem to suggest that this extreme geographical population is not currently endangered. [ABSTRACT FROM AUTHOR]

In general, studies on plant phenotypic plasticity concentrate on plant responses to different levels of a single environmental factor. Under natural conditions, however, multiple environmental factors often vary simultaneously. I studied the consequences for lifetime fitness caused by single treatments or treatment combinations by investigating patterns of phenotypic plasticity within and between generations. The parental plants (three genotypes of the annual plant Arabidopsis thaliana) received zero, one or two stress treatments at an early life‐stage. The treatments included wounding, shading, chilling, and their pairwise combinations. In the second generation, offspring of treated plants received either the parental or no treatment. Offspring of non‐treated plants were reared under all treatment conditions. Plants responded strongly to the treatments, especially through delayed reproduction, which positively affected lifetime fitness. Notably, treatment combinations triggered stronger plastic responses on average. Because the delay in reproduction was offset by a delay in senescence, the treatments resulted in a fitness gain instead of a loss. However, under adverse environmental conditions, this delay represents a potential fitness cost, especially when the time for reproduction is limited. The treatments 'wounding' and 'shading' triggered parental effects that increased fitness only in plants that themselves received the treatment. Untreated offspring of wounded or shaded parents performed like control plants. Also, these parental effects were not accompanied by potential fitness costs, such as delayed reproduction. Chilling triggered genotype‐specific parental effects that increased or reduced fitness. Of the treatment combinations only 'wounding' and 'shading' resulted in genotype‐specific parental effects that increased or reduced fitness independently of offspring treatment. These results suggest that the response of annual plants to treatment combinations triggers predominantly within‐generation plastic responses that include potential fitness costs, which cannot be inferred from studies that manipulate environmental factors individually. Therefore, single treatment studies likely underestimate the costs of plasticity in natural environments. [ABSTRACT FROM AUTHOR]

This paper demonstrates the application of aerial multispectral images in cotton plant phenotyping. Four phenotypic traits (plant height, canopy cover, vegetation index, and flower) were measured from multispectral images captured by a multispectral camera on an unmanned aerial system. Data were collected on eight different days from two fields. Ortho-mosaic and digital elevation models (DEM) were constructed from the raw images using the structure from motion (SfM) algorithm. A data processing pipeline was developed to calculate plant height using the ortho-mosaic and DEM. Six ground calibration targets (GCTs) were used to correct the error of the calculated plant height caused by the georeferencing error of the DEM. Plant heights were measured manually to validate the heights predicted from the imaging method. The error in estimation of the maximum height of each plot ranged from -40.4 to 13.5 cm among six datasets, all of which showed strong linear relationships with the manual measurement (R2 > 0.89). Plot canopy was separated from the soil based on the DEM and normalized differential vegetation index (NDVI). Canopy cover and mean canopy NDVI were calculated to show canopy growth over time and the correlation between the two indices was investigated. The spectral responses of the ground, leaves, cotton flower, and ground shade were analyzed and detection of cotton flowers was satisfactory using a support vector machine (SVM). This study demonstrated the potential of using aerial multispectral images for high throughput phenotyping of important cotton phenotypic traits in the field. [ABSTRACT FROM AUTHOR]

Phenotypic plasticity is important for species responses to global change and species coexistence. Phenotypic plasticity differs among species and traits and changes across environments. Here, we investigated phenotypic plasticity of the widespread grass Arrhenatherum elatius in response to winter warming and frost stress by comparing phenotypic plasticity of 11 geographically and environmentally distinct populations of this species to phenotypic plasticity of populations of different species originating from a single environment. The variation in phenotypic plasticity was similar for populations of a single species from different locations compared to populations of functionally and taxonomically diverse species from one environment for the studied traits (leaf biomass production and root integrity after frost) across three indices of phenotypic plasticity (RDPI, PIN, slope of reaction norm). Phenotypic plasticity was not associated with neutral genetic diversity but closely linked to the climate of the populations' origin. Populations originating from warmer and more variable climates showed higher phenotypic plasticity. This indicates that phenotypic plasticity can itself be considered as a trait subject to local adaptation to climate. Finally, our data emphasize that high phenotypic plasticity is not per se positive for adaptation to climate change, as differences in stress responses are resulting in high phenotypic plasticity as expressed by common plasticity indices, which is likely to be related to increased mortality under stress in more plastic populations. Phenotypic plasticity of populations within a single species varied as much as phenotypic plasticity among functionally and taxonomically diverse species, all stemming from the same environment, indicating a high degree of selection on the studied traits across three indices of phenotypic plasticity (RDPI, PIN, slope of reaction norm). Levels of phenotypic plasticity were not associated with neutral genetic diversity but closely linked to the climate of origin of the populations with populations stemming from warmer and more variable climates showing higher phenotypic plasticity, implying local adaptation of phenotypic plasticity itself. Finally, our data emphasizes that high phenotypic plasticity is not per se positive for adaptation to climate change, as mortality increased in parallel. [ABSTRACT FROM AUTHOR]

Increasingly large presence‐only survey datasets are becoming available for use in conservation assessments. Potentially, these records could be used to determine spatial patterns of plant species rarity and endemism. We test the integration of a large South Korean species record database with Rabinowitz rarity classes. Rabinowitz proposed seven classes of species rarity using three variables: geographic range, habitat specificity, and local population size. We estimated the range size and local abundance of 2,215 plant species from species occurrence records and habitat specificity as the number of landcover types each species' records were found in. We classified each species into a rarity class or as common, compared species composition by class to national lists, and mapped the spatial pattern of species richness for each rarity class. Species were classed to narrow or wide geographic ranges using 315 km, the average from a range size index of all species (Dmax), based on maximum distance between observations. There were four classes each within the narrow and wide range groups, sorted using cutoffs of local abundance and habitat specificity. Nationally listed endangered species only appeared in the narrow‐range classes, while nationally listed endemic species appeared in almost all classes. Species richness in most rarity classes was high in northeastern South Korea especially for species with narrow ranges. Policy implications. Large presence‐only surveys may be able to estimate some classes of rarity better than others, but modification to include estimates of local abundance and habitat types, could greatly increase their utility. Application of the Rabinowitz rarity framework to such surveys can extend their utility beyond species distribution models and can identify areas that need further surveys and for conservation priority. Future studies should be aware of the subjectivity of the rarity classification and that regional scale implementations of the framework may differ. Increasingly available large species observation datasets provide opportunity for greater insights about landscape biodiversity and patterns of species rarity than simply applying species distribution models. We assess the species rarity classification and spatial results of integrating Rabinowitz (1981) species rarity classes with 2,215 plant species from a national‐scale survey. [ABSTRACT FROM AUTHOR]

Summary: Heteromorphic diaspores (fruits and seeds) are an adaptive bet‐hedging strategy to cope with spatiotemporally variable environments, particularly fluctuations in favourable temperatures and unpredictable precipitation regimes in arid climates.We conducted comparative analyses of the biophysical and ecophysiological properties of the two distinct diaspores (mucilaginous seed (M+) vs indehiscent (IND) fruit) in the dimorphic annual Aethionema arabicum (Brassicaceae), linking fruit biomechanics, dispersal aerodynamics, pericarp‐imposed dormancy, diaspore abscisic acid (ABA) concentration, and phenotypic plasticity of dimorphic diaspore production to its natural habitat and climate.Two very contrasting dispersal mechanisms of the A. arabicum dimorphic diaspores were revealed. Dehiscence of large fruits leads to the release of M+ seed diaspores, which adhere to substrata via seed coat mucilage, thereby preventing dispersal (antitelechory). IND fruit diaspores (containing nonmucilaginous seeds) disperse by wind or water currents, promoting dispersal (telechory) over a longer range.The pericarp properties confer enhanced dispersal ability and degree of dormancy on the IND fruit morph to support telechory, while the M+ seed morph supports antitelechory. Combined with the phenotypic plasticity to produce more IND fruit diaspores in colder temperatures, this constitutes a bet‐hedging survival strategy to magnify the prevalence in response to selection pressures acting over hilly terrain. [ABSTRACT FROM AUTHOR]

ContentsSummary1253I.Introduction1253II.What is the rate and molecular spectrum of spontaneous epimutations?1254III.Do spontaneous epimutations have phenotypic consequences?1257IV.Conclusion and discussion1258Acknowledgements1258References1258 Summary: Heritable gains or losses of cytosine methylation can arise stochastically in plant genomes independently of DNA sequence changes. These so‐called 'spontaneous epimutations' appear to be a byproduct of imperfect DNA methylation maintenance and epigenome reinforcement events that occur in specialized cell types. There is continued interest in the plant epigenetics community in trying to understand the broader implications of these stochastic events, as some have been shown to induce heritable gene expression changes, shape patterns of methylation diversity within and among plant populations, and appear to be responsive to multi‐generational environmental stressors. In this paper we synthesized our current knowledge of the molecular basis and functional consequences of spontaneous epimutations in plants, discuss technical and conceptual challenges, and highlight emerging research directions. [ABSTRACT FROM AUTHOR]

From a series of shade tolerance screening trials conducted in an outdoor Shade Tolerance Screening Laboratory, 22 forages (16 grasses and 6 legumes) were selected for quality evaluation. The forages were grown under non-shade (100% of full sun, the control), moderate shade (45%), and dense shade (20%) with adequate water and nutrients and free of competition from other plants. All 22 forages had equal or higher percent crude protein (%CP) and CP yield (g pot−1) under moderate shade than in the control. Under dense shade, 22 and 18 forages had equal or higher %CP and CP yield than in the control, respectively. Under moderate and dense shade, 14 and 15 forages, respectively, maintained relative feed value (RFV) equal to that in the control. Legumes had higher %CP and RFV than grasses with no differences for CP yield. Relative distance plasticity index (RDPI), an indicator of a species' adaptability to different environments, suggested grasses maintained RFV better than legumes under shade, while legumes were more resilient under shade in maintaining %CP than grasses. Our results suggest most grass and legume forages will maintain or have improved quality when grown in agroforestry practices with light to moderate shade compared to forages grown in open pastures. [ABSTRACT FROM AUTHOR]

Genetic variability is the fundamental requirement of any crop breeding program to develop superior cultivars. The objective of this study was to estimate the genetic variability and find out the correlation among the different quantitative traits of rainfed early lowland rice. The experiment was conducted consecutively two years during 2015 and 2016 in wet season across the four different locations in Regional Agricultural Research Station, Khajura, National Wheat Research Program, Bhairahawa, National Maize Research Program, Rampur, and National Rice Research Program, Hardinath, along the Terai region of Nepal representing subtropical agroclimate. Seven genotypes including Hardinath-1 as standard check variety were evaluated in the randomized complete block design with three replications. Various quantitative traits were measured to investigate the variability and correlation coefficients. All the genotypes and locations showed significant variations for all the traits considered. Genotypic coefficient of variation was lower than phenotypic coefficient of variation for all traits studied. The magnitudes of genotypic coefficient of variations were relatively higher for grain yield, 1000-grain weight, and days to heading. The highest broad sense heritability of 94% was recorded in days to maturity and the lowest heritability of 16% was observed in plant height. Positive and highly significant correlations were found both in genotypic and phenotypic levels between days to heading and days to maturity (rg=0.9999 ⁎⁎, rp=0.997 ⁎⁎), days to heading and grain yield (rg =0.9999 ⁎⁎, rp= 0.9276 ⁎⁎), and days to maturity and grain yield (rg =0.9796 ⁎⁎, rp=0.9174 ⁎⁎). However, negative and highly significant genetic correlation was observed between plant height and 1000-grain weight (rg = -0.9999 ⁎⁎). Thus results indicated that days to heading, days to maturity, grain yield, 1000-grain weight demonstrating higher heritability and remarkable genetic advance could be considered the most appropriate traits for improvement and selection of trait to achieve stable and high yielding early rice genotypes under rainfed environments. [ABSTRACT FROM AUTHOR]

Intraspecific trait variation within natural populations (i.e. intra‐population trait variation, IPTV) is the basic source for selection and can have significant ecological consequences. Higher IPTV may increase a population's niche breath and benefit interspecies competition under a resource‐limited environment, thus affecting the ability of a species to move into novel habitats. However, the reciprocal influences of variation in environmental conditions and phenotypic trait expression in spreading plant populations are not clearly defined. We propose that during invasion, IPTV and its relative change in response to key resource enrichment may increase with the resource deficit of invaded sites, and that this relationship may facilitate plant invasions into resource‐limited environments. We analyzed the invasion trend, IPTV and its response to water enrichment, and moisture variability among populations of an annual grass Brachypodium hybridum in California, United States. We incorporated a genotyping‐by‐sequencing approach, a common garden experiment that had two water level treatments, and public plant and climate databases. Our hypothesis was supported by the observation that for populations that invaded sites with higher spring moisture deficit, both their seed biomass IPTV (for the water‐enriched treatment only) and relative change of the IPTV across water treatments were larger when examined in the common garden experiment. A generally north to south spreading direction was found in these B. hybridum populations, towards a drier and warmer climate exhibiting higher moisture deficit for plant growth. Our results suggest a role for interactions between IPTV (rather than trait means) and environmental resource availability in promoting plant invasions, providing new insights into the significance of IPTV in shaping plant geographic distributions. [ABSTRACT FROM AUTHOR]

Seasonal developmental plasticity, which consists of season‐dependent alternations of developmental processes, has evolved to produce optimal phenotypes depending on specific periods in a year. For example, many phenological events in plants, such as flowering, fruiting, bud blast, bud formation, and growth cessation, are often controlled seasonally. Although temperature and photoperiod are the two major seasonal cues for such responses, the importance of phase lag between annual oscillations of the two signals has been unexplored, despite its universal nature in the context of seasonal environments. In this article, the phase‐lag calendar hypothesis (New Phytologist, 210, 2016, 399), especially the one between temperature and photoperiod, is explained using meteorological data obtained from central Japan as an example. We set forth to show how, for a narrow window in time of a couple of weeks in a year, simple threshold responses to these two signals that differ in annual oscillation phases are enough to make developmental plasticity to be expressed as phenological events. The properties of the underlying mechanisms of the events in different seasons are further predicted, and the responses are compared with reported empirical examples. Because many organisms have evolved under the phase lag between photoperiod and temperature, the developmental plasticity in response to the phase lag should be evaluated for diverse organisms. Although temperature and photoperiod are the two major seasonal cues for organismal responses, the importance of phase lag between annual oscillations of the two signals has been unexplored, despite its universal nature in the context of seasonal environments. In this article, the phase‐lag calendar hypothesis, especially the one between temperature and photoperiod, is explained using meteorological data obtained from central Japan as an example. [ABSTRACT FROM AUTHOR]

Highlights • Grain quality associated with environmental conditions between GS31 and 200 °Cd after flowering. • In stressful environments, trade-offs between yield and quality were important. • Water soluble carbohydrates were the crux of these trade-offs. • Breeding targets "specialist" phenotypes for grain and fodder but traits meeting market standards spread across types. • "Generalist" phenotypes can accommodate multiple agronomic uses but specialists are required where trade-offs are involved. Abstract The profitability of oat crops depends on quality attributes in relation to milling and hay marketing standards. The aims of this paper were to (i) quantify grain and hay quality traits in varieties and advanced grain, hay and grazing oat lines, and (ii) analyse the effect of line, environment and their interaction from the viewpoint of phenotypic plasticity. The experiment included 29 lines grown in the winter-rainfall region of South Australia. Grain traits included hectolitre weight, screenings, groat percentage, brightness and concentration of oil and protein. Hay traits, measured at GS71, included digestibility, crude protein, water soluble carbohydrates, acid detergent fibre, and neutral detergent fibre. High temperature, high vapour pressure deficit, and water deficit in the developmental window from GS31 to 200 °Cd after GS60 reduced hectolitre weight and groat percentage, and increased screenings. For hay, the proportion of water soluble carbohydrates declined, the proportion of both acid detergent fibre and neutral detergent fibre increased, and digestibility decreased with higher minimum temperature in a window from approx. −500 to +500 °Cd centred at anthesis. For both grain and hay, current lines returned high yield and high quality in favourable environments, where further improvement could focus on yield and maintenance of quality. In stressful environments, trade-offs between yield and quality were important; water soluble carbohydrates were the crux of these trade-offs. For grain, high concentration of water soluble carbohydrates favoured high hectolitre weight, low screenings and high groat percentage, at the expense of yield. For hay, high concentration of water soluble carbohydrates associated with higher digestibility and lower fibre, at the expense of yield. Nitrogen adds a layer of complexity to these relations, which were partially captured by leaf greenness measured with SPAD. Greener leaves associated with lower concentration of water soluble carbohydrates, hence capturing the established negative correlation between nitrogen and water soluble carbohydrates. Greener leaves associated positively with yield and protein concentration in grain and hay, lower digestibility and higher neutral (and acid) detergent fibre. Whereas the breeding program targets "specialist" phenotypes for grain and fodder, quality traits meeting market standards were spread across types. "Generalist" phenotypes can accommodate multiple agronomic uses but specialists are required where trade-offs are involved. [ABSTRACT FROM AUTHOR]

Summary: With the advent of rapid genotyping and next‐generation sequencing technologies, genome‐wide association study (GWAS) has become a routine strategy for decoding genotype–phenotype associations in many species. More than 1000 such studies over the last decade have revealed substantial genotype–phenotype associations in crops and provided unparalleled opportunities to probe functional genomics. Beyond the many 'hits' obtained, this review summarizes recent efforts to increase our understanding of the genetic architecture of complex traits by focusing on non‐main effects including epistasis, pleiotropy, and phenotypic plasticity. We also discuss how these achievements and the remaining gaps in our knowledge will guide future studies. Synthetic association is highlighted as leading to false causality, which is prevalent but largely underestimated. Furthermore, validation evidence is appealing for future GWAS, especially in the context of emerging genome‐editing technologies. Significance Statement: This review summarizes the latest advances in generating an overall view of the genetic architecture associated with crop complex traits, and discusses how these updated insights will guide future studies. A multiple‐causal‐allele hypothesis was formulated to explain the increasingly common artifact/synthetic associations. [ABSTRACT FROM AUTHOR]

The aim of this project was to compare the phenotypic responses of global populations of Lythrum salicaria in cold/dry and hot/humid environments to determine if phenotypic plasticity varied between the native and invasive ranges, and secondarily if this variation was linked to genetic diversity. Common garden studies were conducted in Třeboň, Czech Republic, and Lafayette, Louisiana, USA (cold/dry vs. hot/humid garden, respectively), using populations from latitudinal gradients in Eurasia and North America. Lythrum salicaria seeds collected from the same maternal plants across these latitudinal gradients were germinated and grown in Třeboň and Lafayette. Tissue masses (above-, below-ground, inflorescence and total) of these individuals were assessed at the end of each growing season (2006–2008). Worldwide field measurements of L. salicaria height were made by volunteers from 2004–2016. Biomass and height data were analyzed using the General Linear Model framework and multivariate techniques. Molecular markers (amplified fragment length polymorphisms) of individuals used in the common garden study were analyzed using traditional genetic diversity metrics and Bayesian clustering algorithms in STRUCTURE. Reaction norms were developed from differences in maternal plant responses in Třeboň versus Lafayette. In the common garden studies, stem/leaf, root and total biomass generally were highest for individuals grown from seeds collected in the southern part of the range in the cold garden, particularly by the third year of the study. In contrast, inflorescence biomass in the cold garden was higher by the third year in individuals from mid-latitude populations. As measured by volunteers, plants were taller in Eurasia than in North America moving from north to south with the pattern switching southward of 40°N latitude. Genetic diversity was similar between native and non-native invasive populations regardless of geographical origin of the seed and was not significantly different in the GLM Select model (p > 0.05). Reaction norm slopes showed that Eurasia had larger values than North America for reaction norms for above-ground and total biomass. Plants from the seeds of mother plants from Turkey had wide variation in total biomass when grown in Třeboň versus Lafayette; this variation in response within certain populations may have contributed to the lack of population-level differences in plasticity. These results indicate no loss of genetic diversity for L. salicaria during its North American invasion, nor reduction in plastic tissue allocation responses to a varying environment, which may help explain some of its invasive qualities and which could be of adaptive value under changing future environments. [ABSTRACT FROM AUTHOR]

Premise of the Study: Ecologists generally agree that weak interspecific competition for light contributes to high plant species diversity in ecosystems with nutrient‐poor soils. However, the role of competition for light in such ecosystems that are also maintained by fire is poorly understood. I quantified intra‐ and interspecific competition for light in a fire‐maintained nutrient‐poor pine savanna by contrasting the effects of conspecific and heterospecific neighbors of the pale pitcher plant, Sarracenia alata. Methods: Accounting for initial neighbor abundance/aboveground production and initial transplant size, I measured growth and survival of small and large pitcher plant ramets of Sarracenia alata transplanted to the vicinity of natural, undisturbed mixtures of large pitcher plants and their heterospecific neighbors in the field. I tested competition for light and nutrients by clipping conspecific neighbors and by excluding prey from unclipped neighbors of transplants. I tested interspecific competition by uprooting heterospecific neighbors. Key Results: Plant survivorship increased when conspecific neighbors were clipped and/or starved but not when heterospecific neighbors were uprooted. Small pitcher plants benefited from clipping large conspecific neighbors, suggesting that competition for light was important. Large pitcher plants benefited from excluding prey from their neighbors, with no additional benefit of clipping, suggesting that competition for prey limited their survival. Transplants produced new pitchers that were taller with narrower openings (i.e., shade avoidance) when heterospecific neighbors were left intact but not when conspecifics were unclipped. Conclusions: Results demonstrate size‐dependent intraspecific competition for light and nutrients and interspecific shade avoidance in Sarracenia alata, which could be important to understanding species coexistence in fire‐maintained nutrient‐poor ecosystems. [ABSTRACT FROM AUTHOR]

The plasticity of functional traits promotes invasiveness of a species. Biomass allocation, as one of these traits, is responsible for resource acquisition, and its plastic modifications can be of adaptive value in new environments before any genetic adaptations may occur. Our aim was to compare in situ biomass allocation in aboveground and belowground organs in an Antarctic and a Polish population of annual bluegrass (Poa annua), the only alien plant species successfully invading Antarctica. The Antarctic population was characterised by three times lower aboveground biomass, more compact plant growth habit and higher fraction of biomass allocated into belowground organs than in the Polish population. The differences between populations are probably a result of adaptation to local conditions. The modifications of the studied traits in the Antarctic population are most likely a response to extreme atmospheric and edaphic conditions and enable the species to survive and spread in this hostile environment. Our results are in accordance with the balanced growth hypothesis. At the same time, these trait values enhance species performance under Antarctic conditions making P. annua a potential threat to local plant communities under altering climate changes and growing human impact scenario. [ABSTRACT FROM AUTHOR]

Summary: Arbuscular mycorrhizal (AM) symbioses can improve plant tolerance to multiple stresses. We compared three AM fungi (AMF) from different genera, one of them isolated from a dry and saline environment, in terms of their ability to increase tomato tolerance to moderate or severe drought or salt stress. Plant physiological parameters and metabolic profiles were compared in order to find the molecular mechanisms underlying plant protection against stress.Mycorrhizal growth response was determined, and ultrahigh‐performance LC‐MS was used to compare the metabolic profile of plants under the different treatments.All AMF increased plant tolerance to stress, and the positive effects of the symbiosis were correlated with the severity of the stress. The AMF isolated from the stressful environment was the most effective in improving plant tolerance to salt stress. Differentially accumulated compounds were identified and the antistress properties of some of them were confirmed.We demonstrate that AM symbioses increase plant metabolic plasticity to cope with stress. Some responses were common to all AMF tested, while others were specifically related to particular isolates. Important metabolism reprograming was evidenced upon salt stress, and we identified metabolic pathways and compounds differentially accumulated in mycorrhizas that may underlie their enhanced tolerance to stress. [ABSTRACT FROM AUTHOR]

Kernel moisture content at harvest stage (KMC) is an important factor affecting maize production, especially for mechanical harvesting. We investigated the genetic basis of KMC using an association panel comprising of 144 maize inbred lines that were phenotypically evaluated at two field trial locations. Significant positive or negative correlations were identified between KMC and a series of other agronomic traits, indicating that KMC is associated with other such traits. Combining phenotypic values and the Maize SNP3K Beadchip to perform a genome-wide association study revealed eight single nucleotide polymorphisms (SNPs) associated with KMC at P = 0.001 using a mixed linear model (PCA+K). These significant SNPs could be converted into five quantitative trait loci (QTLs) distributed on chromosomes 1, 5, 8, and 9. Of these QTLs, three were colocalized with genomic regions previously reported. Based on the phenotypic values of the alleles corresponding to significant SNPs, the favorable alleles were mined. Eight maize inbred lines with low KMC and harboring favorable alleles were identified. These QTLs and elite maize inbred lines with low KMC will be useful in maize breeding. [ABSTRACT FROM AUTHOR]

Grain number per panicle is a major component of rice yield that is typically controlled by many quantitative trait loci (QTLs). The identification of genes controlling grain number per panicle in rice would be valuable for the breeding of high-yielding rice. The Oryza glaberrima chromosome segment substitution line 9IL188 had significantly smaller panicles compared with the recurrent parent 9311. QTL analysis in an F2 population derived from a cross between 9IL188 and 9311 revealed that qgnp7(t), a major QTL located on the short arm of chromosome 7, was responsible for this phenotypic variation. Fine mapping was conducted using a large F3 population containing 2250 individuals that were derived from the F2 heterozygous plants. Additionally, plant height, panicle length, and grain number per panicle of the key F4 recombinant families were examined. Through two-step substitution mapping, qgnp7(t) was finally localized to a 41 kb interval in which eight annotated genes were identified according to available sequence annotation databases. Phenotypic evaluation of near isogenic lines (NIL-qgnp7 and NIL-qGNP7) indicated that qgnp7(t) has pleiotropic effects on rice plant architecture and panicle structure. In addition, yield estimation of NILs indicated that qGNP7(t) derived from 9311 is the favorable allele. Our results provide a foundation for isolating qgnp7(t). Markers flanking this QTL will be a useful tool for the marker-assisted selection of favorable alleles in O. glaberrima improvement programs. [ABSTRACT FROM AUTHOR]

Fruit size and shape are the primary criteria for domestication and improvement of tomato. The varying sizes and shapes of tomato fruit further signify their importance as agronomic traits. Here, we characterized a tomato mutant, smaller fruit (sf), which bears relatively small and ovoid fruits compared with the large and flat fruits of the wild-type (WT). Phenotypic measurements and histological analyses revealed that fruit diameter but not fruit length of the sf mutant decreased compared with that of the WT. This phenotypic change was attributed to significant decreases in locule number and pericarp cell layers in a transverse direction, which resulted in the transition of fruit shape from flat in the WT to ovoid in sf. Comparison of the transcriptomes of ovaries of sf with the WT using RNA-Seq identified 2596 differentially expressed genes, in which 1737 genes significantly were up-regulated and 859 genes were dramatically down-regulated in the sf ovary. Further analyses confirmed that some genes, such as CRCa, CNRs, CYCs, WUS, SUNs, OFRs, CDKs, participate in regulation of fruit size and shape of sf mutant. Thus, our study adds a new genetic resource regarding fruit size and shape of tomato, and provides a valuable basis for understanding molecular regulation of small and ovoid fruit of the sf mutant. [ABSTRACT FROM AUTHOR]

Highlights • Phenotypic plasticity is exceptionally high in A. adscensionis. • Survival in environmental heterogeneity is due to specific anatomical modifications. • Sclerification protects plants organs from collapse and desiccation. • Water conservation is a prime strategy in A. adscensionis for survival. Abstract Aristida adscensionis L. is a widely distributed grass species that particularly invades Potohar region (arid/semi-arid conditions) of the country. Exploration of adaptive components in this grass in relation to altitudinal gradient is the first attempt. Plant samples were collected from 6 different altitudinal ranges, viz. 400, 600, 800, 1000, 1200 and 1400 m a.s.l. Morpho-anatomical and physiological features along altitudinal gradient varied significantly that showed phenotypic plasticity in this species to inhabit a variety of environmental conditions. Stomata at 400 m altitude were larger and rhomboid-shaped, which changed to narrowly elliptic at moderate elevations and circular at high elevations. Growth and biomass production were maximum at 800–1000 m a.s.l. along with most of the morpho-anatomical and physiological features like proportion of vascular tissue, nutrient uptake, and chlorophyll pigments. Xeromorphy was high in plants colonisng at 1200 m elevations, which was indicated by an intensive sclerification, increased amount of storage parenchyma, increased vascular bundle number, deeply grooved bulliform cells, and dense pubescence on adaxial leaf surface. Leaf succulence was the unique feature in plants inhabiting 1400 m elevation. Another prominent feature was the development of chlorenchyma inner to stem epidermis. All these features reflect the tolerance capacity of A. adsecnsionis against environmental adversaries like salinity, aridity and low temperatures of the Potohar region. [ABSTRACT FROM AUTHOR]

In the absence of genetic diversity, plants rely on the capacity of phenotypic plasticity to cope with shifts in environmental conditions. Understanding the mechanisms behind phenotypic plasticity and how local phenotypic adjustments are transferred to clonal offspring, will provide insight into its ecological and evolutionary significance. Epigenetic changes have recently been proposed to play a crucial role in rapid environmental adaptation. While the contribution of epigenetic changes to phenotypic plasticity has been extensively studied in sexual reproducing model organisms, little work has been done on vegetative generations of asexual reproducing plant species. We studied the variability of DNA methylation and bud set phenology of the Lombardy poplar (Populus nigra cv. Italica Duroi), a cultivated tree representing a single genotype worldwide distributed since the eighteenth century. Bud set observations and CpG methyl polymorphisms were studied on vegetative offspring resulting from cuttings grown for one season in a common glasshouse environment. The cuttings were collected from 60 adult Lombardy poplars growing in different environments. The physiological condition of the cuttings was determined by measuring weight and nutrient condition. Methylation sensitive amplified polymorphisms were used to obtain global patterns of DNA methylation. Using logistic regression models, we investigated correlations among epigenotype, bud phenology, and the climate at the home site of the donor trees, while accounting for physiological effects. We found significant epigenetic variation as well as significant variation in bud phenology, in the absence of genetic variation. Remarkably, phenology of bud set observed at the end of the growing season in the common environment was significantly correlated with climate variables at the home site of the mother trees, specifically the average temperature of January and monthly potential evapotranspiration. Although we could not directly detect significant effects of epigenetic variation on phenology, our results suggest that, in the Lombardy poplar, epigenetic marks contribute to the variation of phenotypic response that can be transferred onto asexually reproduced offspring resulting in locally adapted ecotypes. This contributes to the growing evidence that epigenetic-based transgenerational inheritance might be relevant for adaptation and evolution in contrasting or rapidly changing environments. [ABSTRACT FROM AUTHOR]

In a rapidly changing climate, alpine plants may persist by adapting to new conditions. However, the rate at which the climate is changing might exceed the rate of adaptation through evolutionary processes in long-lived plants. Persistence may depend on phenotypic plasticity in morphology and physiology. Here we investigated patterns of leaf trait variation including leaf area, leaf thickness, specific leaf area, leaf dry matter content, leaf nutrients (C, N, P) and isotopes (δ13C and δ15N) across an elevation gradient on Gongga Mountain, Sichuan Province, China. We quantified inter- and intra-specific trait variation and the plasticity in leaf traits of selected species to experimental warming and cooling by using a reciprocal transplantation approach. We found substantial phenotypic plasticity in most functional traits where δ15N, leaf area, and leaf P showed greatest plasticity. These traits did not correspond with traits with the largest amount of intraspecific variation. Plasticity in leaf functional traits tended to enable plant populations to shift their trait values toward the mean values of a transplanted plants' destination community, but only if that population started with very different trait values. These results suggest that leaf trait plasticity is an important mechanism for enabling plants to persist within communities and to better tolerate changing environmental conditions under climate change. [ABSTRACT FROM AUTHOR]

Plant breeders always face the challenge to select the best individuals. Selection methods are required that maximize selection gain based on available data. When several crosses have been made, the BLUP procedure achieves this by combining phenotypic data with information on pedigree relationships via an index, known as family-index selection. The index, estimated based on the intra-class correlation coefficient, exploits the relationship among individuals within a family relative to other families in the population. An intra-class correlation coefficient of one indicates that the individual performance can be fully explained based on the family background, whereas an intra-class correlation coefficient of zero indicates the performance of individuals is independent of the family background. In the case the intra-class correlation coefficient is one, family-index selection is considered. In the case the intra-class correlation coefficient is zero, individual selection is considered. The main difference between individual and family-index selection lies in the adjustment in estimating the individual's effect depending on the intra-class correlation coefficient afforded by the latter. Two examples serve to illustrate the application of the BLUP method. The efficiency of individual and family-index selection was evaluated in terms of the heritability obtained from linear mixed models implementing the selection methods by suitably defining the treatment factor as the sum of individual and family effect. Family-index selection was found to be at least as efficient as individual selection in Dianthus caryophyllus L., except for flower size in standard carnation and vase life in mini carnation for which traits family-index selection outperformed individual selection. Family-index selection was superior to individual selection in Pelargonium zonale in cases when the heritability was low. Hence, the pedigree-based BLUP procedure can enhance selection efficiency in production-related traits in P. zonale or shelf-life related in D. caryophyllus L. [ABSTRACT FROM AUTHOR]