Leaf Architecture Research Articles

Rapid character scoring and tabulation of large leaf-image libraries using Adobe Bridge.

Digital image libraries are an integral part of specimen-based research. However, coding and extracting metadata for hundreds of specimens on a personal computer can be complex. In addition, most existing workflows require downsampling or platform switching and do not link character data directly to the images. We demonstrate a method to code and embed into images the standard leaf architecture and insect-damage characters that are widely used in paleobotany. Using the visual file browser Adobe Bridge, customizable and searchable keywords can be applied directly and reversibly to individual full-resolution images, and the data can be extracted and formatted into a matrix using scripts. Our approach is intuitive and acts as a digital mimic and complement to the experience of sorting and analyzing specimens in-person. Keywords can be easily customized for other data types that require visual sorting using image libraries.

Critical period of weed control in an interseeded system of corn and alfalfa

AbstractAlfalfa (Medicago sativa L.) hectares in Michigan are declining partly due to reliance on corn (Zea mays L.) silage as a continuous feed source. By interseeding corn and alfalfa, farmers can replace the low alfalfa yield in the establishment year with corn silage while simultaneously establishing alfalfa. A randomized split-block field study was conducted in East Lansing, MI, over 3 yr (2019 to 2021) to determine the critical period of weed control (CPWC) in the interseeded corn and alfalfa system using two corn hybrids with differing leaf architecture (pendulum vs. upright). Whole plots were assigned to corn hybrids interseeded with alfalfa, and subplots were assigned to a surrogate weed, Japanese millet [Echinochloa esculenta (A. Braun) H. Scholz], for the duration of competition treatments. Weed-free and weedy plots were included as controls. At the end of the interseeding year, corn was harvested, while alfalfa was harvested the following year. The CPWC is made up of two components: the critical timing of weed removal (CTWR) and the critical weed-free period (CWFP). Corn hybrid had no impact on the CTWR or CWFP for interseeded corn or alfalfa. Averaged across hybrids, the CTWR was 303 growing degree days (GDD), and CWFP was estimated to be greater than the study duration. The CTWR in the first cutting of alfalfa was estimated to be 369 GDD. The CWFP was estimated to be 394 GDD for a 5% acceptable yield loss for the first alfalfa cutting. Identification of the CPWC in the interseeded system will increase adoption and interest in other interseeded systems that can mitigate potential negative environmental and economic impacts of monoculture agriculture.

A New Species of Comptonia (Myricaceae) from the Early Miocene of Central Inner Mongolia, China, and Phytogeographic History of Sweet-Fern.

Simple SummaryThe deciduous shrub Comptonia is a monotypic genus of Myricaceae, which currently is distributed only in eastern North America, with a smaller range than that in other periods of the Cenozoic. By analyzing the macroscopic and microscopic characteristics of the leaves, we describe a new species of Comptonia (i.e., Comptonia hirsuta) from the Hannuoba Formation in Zhuozi, Inner Mongolia, North China. The co-occurring fruits were also studied based on their morphological characteristics, which were assigned to Comptonia tymensis. Variation in the distribution range of Comptonia indicates the influence of global cooling on the expansion of this plant. Furthermore, the Bering Land Bridge played an important role in the migration from North America to East Asia. The Thulean route may have provided an opportunity for plant exchange between western Europe and eastern North America. Moreover, the reason for the disappearance of Comptonia from China according to the analysis of the changes in both the global climate and the distribution of Comptonia fossils is also discussed. It is suggested that the climatic changes after the late Miocene and the progenitive pattern of Comptonia together caused the disappearance of Comptonia in China.Comptonia (Myricaceae) is well known as a monotypic genus living only in eastern North America; however, fossils show that the genus occurred extensively in the Northern Hemisphere during the Cenozoic. We observed dozens of Comptonia leaf fossils from the early Miocene in Zhuozi, China. The leaf architecture characteristics and epidermal features of the fossil specimens are described in detail here for the first time, and they were assigned to a new species: Comptonia hirsuta. The fruit fossils collected simultaneously from the same layer were assigned to Comptonia tymensis. The global fossil records indicate that the spatial distribution range of Comptonia reached its peak in both the Eocene and Miocene as two warm periods and then gradually decreased in the Oligocene, as well as after the late Miocene, because of the cooling global climate. Furthermore, the Comptonia taxon in East Asia may have migrated from North America via the Bering route in the late Paleocene or Eocene. Plant exchange between western Europe and eastern North America possibly occurred during the Eocene via the Thulean route. Phytogeographic variation in the Comptonia fossils from China also indicates that the reason for the disappearance of Comptonia from China may not only be due to the prolonged cooling and drying after the late Miocene, but also due to its progenitive pattern.

Lauraceous palmately lobed leaf from the middle Cretaceous Cintura Formation (Albian–Cenomanian), Sonora, Mexico: Identification based on two comparative models

A new middle Cretaceous trilobed leaf, Araliaephyllum silvapinedae sp. nov., collected near the town of Cabullona, Sonora, Mexico, in La Cintura (Albian–Cenomanian) Formation, is described and identified through two comparative methods: a leaf architecture analysis and the morphometric analysis of its shape. These allowed close comparison of the Cabullona material with extant and fossil taxa. The results of both the comparative methods demonstrate that the leaf of the new fossil plant is related to Araliaephyllum and Pabiania, the former being the one with which it shares most characteristics, both in leaf architecture and in shape. The analyses further confirm close morphological similarity between Araliaephyllum and Pabiania, as well as their relationship with Laurales, supporting the recognition of a new species for the Sonoran material.

Effects of CRISPR/Cas9 generated drooping leaf (dl) alleles on midrib and carpel formations in Oryza sativa Nipponbare.

We generated drooping leaf rice mutants by CRISPR/Cas and identified two novel alleles with specific editing that allow underpinning of the function of the DL protein domain towards midrib and carpel formations. The DROOPING LEAF (DL) gene plays an essential role in regulating midrib formation and carpel specification in rice and other grass species, but the specific function of DL protein domains in different developmental processes is unclear. Analysis of different dl mutant alleles will allow dissecting the function of DL. Here, we generated Nipponbare rice dl mutants using CRISPR/Cas gene editing and identified two novel dl alleles with different effects on midrib formation and carpel development. Phenotypic and genotypic analysis of T0 and segregated T1 edited lines showed that while dl-51S allele (a 3bp deletion and a serine deletion at position 51) reduces midrib sizes and produces normal carpels, the dl-50LS allele (a 6bp deletion and a leucine-serine deletion at position 50-51) causes the lack of midribs and abnormal stigma. This result indicates that the 51-serine is important for midrib formation and the 50-leucine is essential for midrib and carpel development. These dl mutant alleles contribute to the DL gene functional analysis and to gain insights into possible modifications of leaf architecture of rice and other grass species.

Classifying fifty-seven Cucumis (Cucurbitaceae) accessions into six species using leaf architectural traits

Abstract. Masungsong LA, Alcala AA, Buot IE Jr., Belarmino MM. 2022. Classifying fifty-seven Cucumis (Cucurbitaceae) accessions into six species using leaf architectural traits. Biodiversitas 23: 4006-4017. In gene banks, there are myriads of accessions that need to be studied, grouped, classified and organized to the proper taxon and hence, be able to manage the accessions efficiently. Using leaf architecture traits, it is the objective of this study to determine the identity and classify the 57 Cucumis accessions in the genebank of Hortanova Farm and Research Center, East-West Seed Company, Inc., Lipa City, Batangas, Philippines. Five hundred thirteen Cucumis leaf samples across the 57 accessions were collected, measured, thoroughly investigated, and described using leaf architectural characters. Results of leaf architectural analyses focusing on the blade class, apex angle, secondary vein spacing, tertiary vein angle in relation to primary vein, and areole development, revealed that the 57 accessions can be grouped into six (6) species of Cucumis, namely, C. melo subsp. agrestis (Naudin) Pangalo, C. melo var. texanus Naudin, C. melo var. flexuosus (L.) Naudin, C. zambianus Widrl, J.H.Kirkbr., Ghebret. & K.R.Reitsma, C. sativus L., and C. sativus var. hardwickii (Royle) Gabaev. Cucumis sativus and C. sativus var hardwickii were delineated from the rest of the species for having a macrophyll blade class, an odd lobed acute apex angle and an obtuse tertiary vein angle in relation to the primary vein. This delineation is illustrated in the constructed dichotomous botanical key. Utilizing leaf architecture characters is an effective technique to characterize, identify and classify closely related taxa possessing confusing characters.

Comparative analysis of the leaf architectural characters of Saurauia bontocensis Merr. and Saurauia polysperma (Blanco) Merr. with the application of Digital Image Analysis Software

Abstract. Daipan BPO, Buot IE Jr., Daipan HMO. 2022. Comparative analysis of the leaf architectural characters of Saurauia bontocensis Merr. and Saurauia polysperma (Blanco) Merr. with the application of Digital Image Analysis Software. Biodiversitas 23: 3869-3875. Major confusion still exists among several authors concerning the taxonomy of the dagwey plant. This species is economically significant to the Ikalahan tribe of Luzon, Philippines. Several papers claimed that the plant is Saurauia bontocensis, while others stated that it is Saurauia subglabra. Many botanical websites claimed that S. subglabra is synonymous with S. polysperma, while another article distinguished S. subglabra from S. polysperma. Thus, to help resolve the taxonomic ambiguities, this paper performed a comparative analysis of the leaf architectural characters of S. bontocensis and S. polysperma with the aid of digital image analysis software and cluster analysis. Results revealed that the blade characters alone, delineate the two species, particularly, in terms of the laminar size, shape, symmetry, leaf L:W ratio, base and apex angle, and base shape. Additionally, the leaf venation characters delineate the two species, specifically, on the 2º to 5º vein categories, 2º vein angle, 3º vein course, 3º vein angle to 1º, areolation, freely ending ultimate veins, marginal ultimate venation, and leaf rank. Generally, S. bontocensis have larger, longer, and wider leaves compared with the S. polysperma. The leaf architecture analysis performed in this paper produced a very promising result in differentiating the two Saurauia species and could be used to address some of the taxonomic confusion of these species. The study indicated that S. bontocensis and S. polysperma are two distinct species. Moreover, the use of digital image analysis software was very helpful in the computations of the various blade characters, particularly the digital herbarium exsiccate in the absence of actual leaf samples.

CdS-based artificial leaf for photocatalytic hydrogen evolution and simultaneous degradation of biological wastewater.

Rational design of all-solid-state Z-scheme heterojunction with advanced structure is essential for boosting photocatalytic efficiency. Herein, we design and fabricate a novel Z-scheme photocatalyst with leaf architecture (named artificial leaf) via a simple dipping-calcination (DC) process followed by a successive ionic layer adsorption and reaction (SILAR) strategy. The prepared artificial leaf, composing of CdS, InVO4, and BiVO4, holds advanced leaf-like structure and Z-scheme electron transfer pathway. As a result, this novel artificial leaf exhibits outstanding capability for the harvesting of visible light and superior efficiency for the separation of photogenerated electron-hole pairs, as well as remarkably enhanced photocatalytic performance and stability for H2 evolution (with the rate of 5033μmg-1∙h-1) and pollution degradation (46% pollution can be degraded within 3h).

Numerical Taxonomic Evaluation of Leaf Architectural Morphology of Vitex L. species (Lamiaceae Martinov) in Peninsular Malaysia

A numerical taxonomic is an algorithm method that is used to evaluate scored characters of continuous characters such as leaf architectures. Leaf architecture characters were scored from 11 Vitex species in Peninsular Malaysia (V. gamosepala, V. glabrata, V. longisepala, V. millsii, V. negundo, V. pinnata, V. quinata, V. trifolia, V. vestita, Vitex sp.1 and Vitex sp.2), one subspecies (V. trifolia subsp. litoralis) and two varieties (V. negundo var. bicolor and V. negundo var. cannabifolia) were investigated using herbarium voucher specimens and fresh specimens collected from the fieldwork. Species collected were from Pasoh Forest Reserve, Negeri Sembilan; Gunung Lambak Forest Reserve, Johor; Sungai Dara Forest Reserve, Perak; Proton City, Tanjong Malim, Perak; Gunung Lambak Forest Reserve, Johor; Cameron Highland, Pahang; Herb Walk Garden, Langkawi; and Kg. Pulau Belanga, Kota Bharu, Kelantan. All the studied Vitex species shared leaf architecture as follow: arrangement (opposite), marginal ultimate (looped), position of petiole arrangement- P.O.P.A (marginal) and petiole feature (swollen base). Specimens with single leaf type and presence of petiolule further help in distinguishing Vitex species. The scored data were analysed using Multi-Variate Statistical Package (MVSP) and Phylogenetic Analysis Using Parsimony (PAUP) softwares to obtain similarity values between species and their evolutionary relationship, respectively. Dendogram clades show an overall Gower General Similarity Coefficient (GGSc) value at 0.715 to 0.964 which indicate clear separation at genus and species level while pairwise distance between the in-group and out-group taxa analysed in the neighbour-joining tree was in between 0.26364 to 0.55455 showing that trees were constructed with strong bootstrap support with Consistency Index (CI) 0.6852 (CI) excluding uninformative character = 0.6000, Homoplasy index (HI) 0.3148 (HI excluding uninformative character = 0.4000), Retention Index (RI) 0.5802 and rescaled consistency index (RC) 0.3976. As a conclusion, high similarity in leaf architecture characters of all 11 species, one subspecies and two varieties of Vitex studied in Peninsular Malaysia suggest and support them belongs to the same genus hence supporting the taxonomic significance. This study implicate that leaf architecture morphological characters of vegetative parts can be used in identification to species, subspecies and variety level of this genus and might propose some changes to the placement of taxa hence can be devoted as an improvement for the previous Vitex study.

Rich variant phenotype of Gossypium hirsutum L. saturated mutant library provides resources for cotton functional genomics and breeding

Cotton is not only a raw material for the textile industry, but also an important strategic material. However, traditional breeding methods have narrowed the genetic diversity of current cotton cultivars. Abundant germplasm resources is a solid foundation for breeding, the use of chemical mutagenesis to create abundant mutation is of great significance to cotton breeding. This study used ethyl methanesulfonate (EMS) to mutagenize upland cotton material TM-1. First, we obtained a mutant library with abundant mutations and abundant phenotypes of the leaf, boll, locules numbers and plant architecture,. Second, based on the genome-wide analysis of the leaf and plant structure mutant., it showed that the library had a saturated genome mutations. Further GO and KEGG analysis showed SNPs were significantly enriched in DNA repair and response to hormone, non-homologous end joining (NHEJ) and homologous recombination (HR) pathways, which explained the mutated trait. In addition, we screened candidate gene (Gh_D05G364200) for crumpled leaf by BSA and transcriptome sequencing. Above all, the mutant library we obtained provides abundant resources for cotton functional genomics and breeding.

Leaf architectural analysis of taxonomically ambiguous Hoya lacunosa Blume and Hoya krohniana Kloppenb. & Siar

Abstract. Scott HC, Buot JR IE. 2022. Leaf architectural analysis of taxonomically ambiguous Hoya lacunosa Blume and Hoya krohniana Kloppenb. & Siar. Biodiversitas 23: 2055-2065. The horticulturally important Hoya R.Br. species Hoya lacunosa Blume and Hoya krohniana Kloppenb. & Siar are often mistaken for each other because of their generally similar inflorescence morphology. Based on the hypothesis that leaf venation patterns are genetically fixed, leaf architectural analysis was done to determine the difference between these two taxonomically confusing species. Thirty fully expanded leaves were obtained per species from mature plants of H. lacunosa, H. krohniana and an outgroup, H. pubicorolla. Laminar and venation characters were analyzed using standard leaf architecture protocols. Results show that the main distinction lies in their laminar characters, particularly the base angle and base shape. H. lacunosa samples showed acute to obtuse base angles with cuneate and convex leaf bases, while H. krohniana were found to have obtuse reflex base angles with convex, cordate and rounded leaf bases. Analysis of venation characters shows no considerable difference between the patterns seen in H. lacunosa and the patterns observed in H. krohniana. Further investigation of higher vein orders is recommended. Initial comparison of H. lacunosa pollinaria with the photos of H. krohniana pollinaria from its type description show strikingly similar morphology; for this reason, we also recommend floral morphology comparisons, particularly pollinaria morphology to further establish the similarity and delineation of H. lacunosa and H. krohniana.

Intriguing correlations between leaf architecture and intrinsic water-use efficiency enable selective breeding to mitigate climate challenges.

Intriguing correlations between leaf architecture and intrinsic water-use efficiency enable selective breeding to mitigate climate challenges.

Genotype-specific models for leaf architecture as affected by leaf position and age. Model development and parameterisation using smartphone-based 3D plant scans

Leaf architecture is crucial for optimising light harvesting and photosynthetic efficiency. Three-dimensional functional-structural plant models (FSPMs) are instrumental to analyse light conditions inside the canopy and support breeding for ideal plant types. However, the large amount of data needed for their parameterisation often limits their development and use. In this study, widespread technologies like mobile phones were used to scan leaf architecture under field conditions for multiple genotypes (16 rice genotypes, two planting densities, 22,996 measurements of single leaves), providing data for modelling genotype-specific time-dynamics of leaf architecture. Leaf architecture was analysed with the mobile app PocketPlant3D, which records leaf angles with respect to the zenith and azimuth while the device is moved along leaf blades, and with a ruler for leaf length. Models were derived between leaf curvature traits – parameters of Bézier functions fitted to observed leaf angles – and leaf position and age. Genotype-specific simulated Bézier parameters and leaf length were then used to reproduce curvature of single leaves, which were compared against field observations. The approach successfully reproduced variation of leaf architecture over time, with EF (modelling efficiency), R 2 and MAE (mean absolute error) obtained with cross-validation equal to 0.88, 0.96 and 2.07 cm, respectively. Validation on an independent dataset confirmed the validity of the approach (EF: 0.75, R 2 : 0.87, MAE: 2.82 cm). Handy, inexpensive technologies like mobile phones can successfully support the development and genotype-specific calibration of FSPMs. This opens new opportunities to address questions about optimising canopy structure by jointly defining crop breeding and management strategies. • Leaf architecture is key for canopy light harvesting and photosynthetic efficiency. • The 3D architecture of 22,996 tagged leaves was analysed with the app PocketPlant3D. • Models were developed for the effect of leaf position and age on leaf architecture. • Variation of leaf architecture over time in open field was successfully captured. • Our approach can support development and genotype-specific calibration of 3D models.

Analysis of leaf-architecture characteristics and ecological adaptability of tree species in the upper reaches of the Chishui River

The leaf-architecture characteristics of 15 ligneous plants of the karst region of the upper reaches of the Chishui River were assessed using spatial syntax. Furthermore, the relationship between leaf-architecture characteristics, plant functional traits, and soil water-holding capacity as well as the adaptation of plant architecture to this habitat were explored. The following results were obtained: (1) The integration, connectivity, and control of primary veins are significantly better than those of secondary veins, indicating strong interveinal ranking. The integration, connectivity, and control of evergreen tree species are superior to those of deciduous tree species, suggesting a more complex spatial morphological structure of evergreen leaves. In evergreen trees, the spatial morphological structure of tree leaves is more complex than that of shrubs, while the spatial morphological structure of tree leaves of deciduous trees is simpler than that of shrubs. (2) The dry matter content of the leaves of the investigated 15 ligneous plants ranged from 10.79 to 31.83 mg·g−1. The leaf relative water deficit, maximum net photosynthetic rate, transpiration rate, and the specific leaf area content ranged from 35.15 to 66.53%, 0.4–32 μmol·m−2·s−1, 0.07–0.71 g·cm−2·h−1, and 230.15–585.39 cm2·g−1, respectively. (3) The spatial syntax index is significantly correlated with transpiration rate, leaf relative water deficit, as well as soil maximum and available water-holding capacity. (4) Based on the spatial morphological structure of leaves, four basic modes of the leaf architecture can be classified: evergreen mode with complex morphological leaf-structure, evergreen mode with lower complex morphological leaf-structure, mixed evergreen and deciduous modes with lower complex leaf-morphological structure, and deciduous mode with simple morphological leaf-structure. (5) The spatial morphological structure of leaves in karst areas effectively exposes differences of architecture among different plants. Space syntax effectively represents leaf-architecture characteristics and is important for the study of plant architecture. Understanding plant architecture characteristics and their adaptation to the environment provides a scientific basis for the selection of tree species and planting patterns in the vegetation restoration area.

RIP2 interacts with REL1 to control leaf architecture by modulating brassinosteroid signaling in rice.

RIP2 serves as a negative regulator of leaf inclination through the coordination of BR signaling in rice. Leaf angle is considered as an important morphological trait in rice. Appropriate leaf angle increases the efficiency of sunlight capture and maintains a high level of photosynthesis, ultimately improving crop yield. Our present study demonstrates that RIP2 encodes a RING finger E3 ligase protein that directly binds to ROLLED AND ERECT LEAF 1 (REL1), a key regulator of leaf morphogenesis. Further studies reveal that RIP2 is extensively involved in leaf inclination through the coordination of BR signaling. Repression of RIP2 led to altered phenotypes, including enlarged leaf inclination and fewer tillers. Conversely, rice overexpressing RIP2 exhibited erect leaves. The double mutant rel1 rip2 displayed phenotypes similar to those of rel1, characterized by rolled leaves. Transcriptome profiling of WT, rel1, rip2, and rel1 rip2 mutants revealed that BR and IAA signaling pathways were impaired in rip2. Moreover, rel1, rip2, and rel1 rip2 were insensitive to BR treatment. In summary, these findings demonstrate that RIP2 serves as a negative regulator of leaf inclination, and therefore, provides an approach for the optimization of an ideal plant type.

CANOPY ARCHITECTURE AND GRAIN YIELD OF MAIZE (ZEA MAYS L.) IN THE RAINFOREST OF SOUTHWESTERN NIGERIA

Plant architecture is a key factor for optimum productivity in most crops. Unfortunately, this aspect of maize (Zea mays L.) crop configuration has recieved little attention from researchers in the rainforest ecologies of Nigeria.We investigated the effects of the environment on canopy architecture and, in turn, canopy orientation on grain yield of maize in the rainforest of sw Nigeria. Five maize varieties were planted weekly from March to November of 2016 and 2017 in randomized complete block experiments at the Obafemi Awolowo University Teaching & Research Farm (OAU T&RF). Data were collected on canopy architecture, which was quantified with upper and lower leaf angle (LAUpper and LALower) and leaf orientation values (LOVUpper and LOVLower) obtained at the grain-filling stage.-At maturity, grain yield, along with some of its components (ear length, ear diameter and kernel row number) were also obtained from all plots. The data were subjectedto ANOVA, correlation, regression, and sequential path analyses to determine the relationship of grain yield with canopy architecture. The environment and genotype had significant effects on canopy architecture, grain yield (P = 0.01; R2 ≥ 80 %), and yield components. Leaf orientation value of the upper canopy (LOVUpper), with correlation coefficient r = 0.61** and direct positive causal effect (P = 0.61), rather than LAUpper, LALower and LOVLower, greatly affected grain yield. In conclusion, LOVUpper was the single most important leaf architecture index that positively affected grain yield which, in turn, was influenced greatly by the environment in the rainforest ecology of SW Nigeria

An image dataset of cleared, x-rayed, and fossil leaves vetted to plant family for human and machine learning.

Leaves are the most abundant and visible plant organ, both in the modern world and the fossil record. Identifying foliage to the correct plant family based on leaf architecture is a fundamental botanical skill that is also critical for isolated fossil leaves, which often, especially in the Cenozoic, represent extinct genera and species from extant families. Resources focused on leaf identification are remarkably scarce; however, the situation has improved due to the recent proliferation of digitized herbarium material, live-plant identification applications, and online collections of cleared and fossil leaf images. Nevertheless, the need remains for a specialized image dataset for comparative leaf architecture. We address this gap by assembling an open-access database of 30,252 images of vouchered leaf specimens vetted to family level, primarily of angiosperms, including 26,176 images of cleared and x-rayed leaves representing 354 families and 4,076 of fossil leaves from 48 families. The images maintain original resolution, have user-friendly filenames, and are vetted using APG and modern paleobotanical standards. The cleared and x-rayed leaves include the Jack A. Wolfe and Leo J. Hickey contributions to the National Cleared Leaf Collection and a collection of high-resolution scanned x-ray negatives, housed in the Division of Paleobotany, Department of Paleobiology, Smithsonian National Museum of Natural History, Washington D.C.; and the Daniel I. Axelrod Cleared Leaf Collection, housed at the University of California Museum of Paleontology, Berkeley. The fossil images include a sampling of Late Cretaceous to Eocene paleobotanical sites from the Western Hemisphere held at numerous institutions, especially from Florissant Fossil Beds National Monument (late Eocene, Colorado), as well as several other localities from the Late Cretaceous to Eocene of the Western USA and the early Paleogene of Colombia and southern Argentina. The dataset facilitates new research and education opportunities in paleobotany, comparative leaf architecture, systematics, and machine learning.

Spray solution deposition and Asian rust control in soybean cultivars

ABSTRACT The control of Asian soybean rust depends on fungicide efficacy and the application technology; however, the leaf architecture of soybean cultivars may also interfere in disease control. This study aimed to evaluate Asian rust control and fungicide deposition using spray nozzles in three soybean cultivars. A randomized block design was used, with treatments arranged in a split-plot scheme; the plots were three soybean cultivars (SYN 1561 IPRO, M6410 IPRO, and M6210 IPRO) and the subplots three spray nozzles (11002 BD, AIXR 110015 and TTJ60 11002), in addition to a control with no fungicide application, and four replicates. The volume median diameter, droplet coverage, leaf area index, area under the disease progress curve, 1,000-grain weight and crop yield were evaluated. The 11002BD and AIXR11005 nozzles provided better spray deposition in cultivars with lower leaf area indexes at the R1 phenological stage. Nozzles 11002BD, AIXR110015 and TTJ60 ensured better management of Asian rust than that of the control treatment, regardless of leaf area index. Cultivar SYN1561 obtained the largest grain yield and highest leaf area index in the season with the highest rainfall, regardless of the spray nozzle used.

Characterizing Genotype-Specific Rice Architectural Traits Using Smart Mobile App and Data Modeling

The quantity and quality of light captured by a plant’s canopy control many of its growth and development processes. However, light quality-related processes are not very well represented in most traditional and functional–structural crop models, which has been a major barrier to furthering crop model improvement and to better capturing the genetic control and environment modification of plant growth and development. A main challenge is the difficulty in obtaining dynamic data on plant canopy architectural characteristics. Current approaches on the measurement of 3D traits often relies on technologies that are either costly, excessively complicated, or impractical for field use. This study presents a methodology to estimate plant 3D traits using smart mobile app and data modeling. Leaf architecture data on 16 genotypes of rice were collected during two crop seasons using the smart-app PocketPlant3D. Quadratic Bézier curves were fitted to leaf lamina for estimation of insertion angle, elevation angle, and curve height. Leaf azimuth angle distribution, leaf phyllotaxis, canopy leaf angle distribution, and light extinction coefficients were also analyzed. The results could be used for breeding line selection or for parameterizing or evaluating rice 3D architectural models. The methodology opens new opportunities for strengthening the integration of plant 3D architectural traits in crop modeling, better capturing the genetic control and environment modification of plant growth and development, and for improving ideotype-based plant breeding.

Short communication: Variations in leaf morphological characters of Shorea leprosula in progeny trial stand of a logging concession in Kalimantan, Indonesia

Indonesia has the highest distribution of Dipterocarpaceae members, and Shorea leprosula is one of the species that has a natural hybrid in its habitat. Furthermore, the members have intermediate morphological character with the neighboring species, Shorea curtisii. This study aimed to investigate the morphological variations of Shorea leprosula Miq. Progeny trial in PT Sari Bumi Kusuma. The morphological level of 72 Shorea leprosula in PT Sari Bumi Kusuma was identified through sampling. Furthermore, macroscopic and microscopic observations were conducted, and the measurement data were analyzed using cluster and principal component analyses to explain the morphological variable contribution. The results showed leaf architecture variations in laminar shape, apex shape, base shape, and midrib thickness category. The cluster analyses classified the samples into four cluster groups and they consist of a notophyll leaf size category with a rounded base. Meanwhile, the second group consists of an ellipse laminar shape with medium midrib thickness, and the third has an oblong laminar with an obtuse apex shape. The fourth group has a notophyll leaf size category with an obtuse base. The principal component analysis showed that the base shape has the highest contribution to diversity in the samples.