Phenotypic Plasticity and Genetic Variation of Leaf Pigment Content in a Southern Beech

Physiological, morphological and phenological attributes are potentially adaptive traits that determine functional responses to certain environmental conditions. They are crucial for understanding adaptations to environmental variation along a species natural range. In particular, leaf pigment content can be a good proxy to the physiological and phenological tree state. Our goal was to evaluate the variation in pigment traits among Nothofagus alpina populations in a common garden trail during two years to infer local adaptation and/or phenotypic plasticity. We also aim to analyse the correlation between pigment traits and phenological traits and climatic data from the geographic location of the populations. To comprise the entire range of the species in Argentina, we analysed 400 individuals from eight natural populations coming from four lake watersheds. Pigment traits were estimated using a spectrophotometer and analysed with linear mixed model (LMM). Significant differences among fixed factors (populations - years and watershed – years) were found in chlorophyl a, b, total, carotenoids and anthocyanins concentrations. Higher concentrations were found for 2018, year with the highest number of rainy days and accumulated precipitation. Two populations (Boquete and Tren Tren) were always the most contrasting ones. At population level, the correlation between the means of pigment concentrations and phenological traits was significant in almost all cases. Conversely, the correlation between the means of population pigment concentrations and the main geographic, climatic and bioclimatic variables of the home range were not significant. The significance of the environmental factor (year) in the linear mixed models tested is evidence of phenotypic plasticity of pigment content, suggesting flexibility for acclimatization to moderate inter-annual changes in climatic conditions. The significance of population and watershed and the influence of the family factor on the variance of the pigment traits are evidence of the genetic control as well as the potential adaptive value of leaf pigment content in N. alpina, giving a base for adaptation to a long-lasting change in climate. High correlations between phenological and pigment traits indicate that, in N. alpina, the determination of only one pigment concentration could be used as a proxy of bud burst, senescence and growing degree days.

Leaf Pigment, Phenolic Content, and Production of Green Shallot of Five Different Shallot Varieties

Five shallot varieties namely ‘Bauji’, ‘Bantaeng’, ‘Tuk Tuk’, ‘Rubaru’, and ‘Palasa’ were examined for their leaf pigment, total phenolic content, leaf tissue nutrient analysis, and green shallot production. The experiment was conducted in in Cikabayan greenhouse, IPB University, Dermaga, Bogor, arranged in a randomized complete block design with single factor (variety) and three replications. The observations were carried out three times in the maximum vegetative period, consisting of 20, 30, and 40 days after planting. The result showed that ‘Palasa’ had the highest leaf pigment content, such as chlorophyll a, chlorophyll b, total chlorophyll, and carotenoid, while the anthocyanin content fluctuated between the varieties and observation times. ‘Palasa’ also had the highest sulfur content in the leaf tissues. On the contrary, ‘Palasa’ had the lowest production compared to other the varieties. Meanwhile, ‘Bantaeng’ had the highest green shallot production, total nitrogen, and total phosphorus content in the leaf tissues. Total phenolic content fluctuated in the five varieties and observation times. The highest total phenolic content was in ‘Tuk Tuk’, observed 20 days after planting. The principal component analysis (PCA) showed that the five shallot varieties formed three clusters. The first was ‘Palasa’, the second cluster was ‘Bauji’, ‘Tuk Tuk’, and ‘Rubaru’, while the third cluster was ‘Bantaeng’. ‘Palasa’ had the highest content of leaf pigment, while Bantaeng had the highest leaf production. Leaf pigment and total phenolic content changed along with the increasing plant age in all varieties.

Leaf pigment complex of spring soft wheat cultivars of different maturity groups under different moisture regimes

Creation of new higher productive cultivars of cereal crops is often linked with straightening of degree of resistance to abiotic environmental factors. Indirectly this degree of resistance could be estimated on quantitative change in leaf pigment composition. There is practical interest to compare the activity of pigment complex of flag leaves of wheat cultivars belonging to different maturity groups that could give information on direction of breeding improvement of plant physiological-and-genetic traits under different ecological conditions. Plants of nine breeding lines and two standard cultivars grew in 2016-2018 at the experimental field of FARC of North-East (Kirov) under continental climate conditions with moderately cold winter and warm summer. The study of flag leaves pigment complex allows to discover differences between early and middle-ripening cultivars on investigated parameters in different hydrothermal conditions. During the study years, middle-ripening cultivars accumulated more chlorophyll a than the early ones. On average this excess was about 10%. The studied cultivars were differed on distribution of pigment between structural parts of photosystems: middle-ripening cultivars had more chlorophyll a in reaction centers whereas the amount of the pigment in light-harvesting complexes was not differed. Hydrothermal conditions significantly influenced the differences between cultivar groups. Thus, under dry conditions the content of chlorophyll b and carotenoids in flag leaves of cultivars belonging to both group of maturity had no significant differences. Under normal or moist conditions middle-ripening cultivars contained 11,0-12,6% more chlorophyll b and 7,6-23,1% more carotenoids than the early cultivars. Under dry conditions the two groups of cultivars significantly differed on mass ratio chlorophyll a/b: in the middle-ripening cultivars it was 5,0% higher than in the early ones. Based on chlorophyll a and b content at flowering stage breeding lines С-64, С-65, С-103, and С-129 were selected. The amount of chlorophyll in these genotypes was significantly higher than in Margarita standard cultivar. Within the group of early cultivars, no one exceeded Bazhenka standard by the pigment content. The cultivars of this group reacted on abiotic growing conditions change very much (the amount of precipitations and air temperature): the coefficients of chlorophyll a content variation were 6,5-16,3%, of chlorophyll b content - 26,9-29,7%, of carotenoids content - 4,1-17,2%.

Non-destructive measurement of leaf area and leaf pigments in feijoa trees

ABSTRACT Leaf area (cm2 per leaf) and leaf pigment content are important traits that can be used to better understand a plants physiology. In this study, empirical non-destructive models for leaf area and leaf pigment based on the leaf dimensions, length (L) and width (W) in centimeters, and chlorophyll meter readings were developed for feijoa (Acca sellowiana). The experiment was carried out during January 2016 using five-year-old trees of 60 genotypes, grown under field conditions in the state of Paraná, Brazil. The proposed leaf area (LA) model was L A = 0 . 0022 L 3 + 0 . 1482 W 2 + 0 . 6159 L W + 0 . 1076 (R2 = 0.99). Three current leaf area models found in the literature were also assessed. All of the already created models were less accurate than the model proposed in this article. The proposed leaf pigment models were based on the Falker Chlorophyll Index for Chlorophyll a (A) and b (B), these were C h l a = 2 . 564 A + 13 . 098 B - 42 . 605 (R2 = 0.94), C h l b = 1 . 538 A + 3 . 287 B + 8 . 847 (R2 = 0.86) and C a r o t e n o i d s = 0 . 947 B + 8 . 943 (R2 = 0.88) expressed as µmol m-2 of leaf blade. In conclusion, the proposed models in this study were shown to be a reliable non-destructivel way of estimating A. sellowiana leaf area and leaf pigment.

Antioxidant leaf pigments and variability in vegetable amaranth

Twenty-three vegetable amaranth genotypes were evaluated for variability, interrelationships among antioxidant leaf pigments and foliage yield. Five genotypes found to be a rich source of antioxidant leaf pigments and might be directly selected as antioxidant leaf pigments enriched high yielding varieties. Two genotypes had high content of antioxidant leaf pigments with low yield might be used as donor parents for antioxidant leaf pigments genes to develop transgressive segregant or pigment enriched transgenic vegetable amaranth varieties. The insignificant negative genotypic correlation was observed between total carotene versus all antioxidant leaf pigments, ascorbic acid versus all antioxidant leaf pigments and foliage yield versus rest of all traits. Improvement of vegetable amaranth regarding carotene and ascorbic acid might be possible without compromising yield loss. On the other hand, most of the interrelationships among antioxidant leaf pigments traits indicated that improving of one antioxidant leaf pigment significantly improved the other antioxidant leaf pigments.