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This study investigates dosimetric influence and gradient-analysis of leaf-width of various Multi-leaf-collimators (MLC) from Truebeam and Halcyon linear accelerators. The leaf-width effects of Millennium120 and HD120MLC from Truebeam and SX1 and SX2 from Halcyon were studied using virtual phantom in Eclipse16.1.2 TPS. Target structures consist of bore and wave cylinders of equally spaced projected Planning target volume (PTV) of diameters ranging from 1-to-5 cm and 20 cm length. Treatment plans for all PTVs, and four different MLCs configurations from both machines were created utilizing 6MVFFF beam to deliver dose of 50Gy/25# using IMRT and VMAT. Plans were evaluated using plan quality indices including dose conformity, homogeneity, gradient radius, and Monitor-unit (MU). Also, dose gradients were analyzed by estimating distinct integral volume V D% and paired-t-tests were performed to evaluate statistical differences. All the plan satisfied the minimum criteria of D 95 % ≥prescription dose and V 107 % ≤2cc. Mean conformity and homogeneity indices for SX1MLC(CI = 0.680,HI = 0.022) were found significantly higher and lower than SX2(CI = 0.746,HI = 0.016), Millennium120 (CI = 0.739,HI = 0.012), and HD120MLC(CI = 0.745,HI = 0.017), respectively. However, CI and HI for SX2, Millennium120, and HD120MLC found comparable. Gradient radius enclosing 50 % of isodose observed maximum and minimum for SX1 and HD120MLC, respectively. Plan MUs for Truebeam MLCs were found approximately 25 % higher than Halcyon MLCs. Dose distribution generated using SX2 and Millennium120 found comparable, however p ≤ 0.05 ascertained substantial differences among SX1, Millennium120, and HD120MLC. MLC leaf-width influences intensity-modulation and significantly alters dosimetric outcome depending on the magnitude of the leaf-width. HD120MLC does not show much significant advantages over SX2 and Millennium120 except gradient control. Halcyon SX1MLC produces least effective plan compared to all other MLC types. However, SX2 and Millennium120 can produce plans of comparable quality except plan MUs difference. [ABSTRACT FROM AUTHOR]

Leaf width is a key determinant of planting density and photosynthetic efficiency. In an effort to determine which genes regulate maize plant leaf width, we performed a genome-wide association study (GWAS) of 1.49 × 106 single nucleotide polymorphisms (SNPs) in 80 sequenced backbone inbred maize lines in Jilin Province, China, based upon phenotypic leaf width data from two years. In total, 14 SNPs were identified as being significantly related to leaf width (p < 0.000001), with these SNPs being located on chromosomes 1, 2, 3, 5, 6, 7, 8, and 9. A total of five candidate genes were identified within a mean linkage disequilibrium (LD) distance of 9.7 kb, with a significant SNP being identified within the Zm00001d044327 candidate gene. RNA was then isolated from 12 different inbred maize lines from this GWAS study cohort and was used to conduct qPCR analyses which revealed significant differences in Zm00001d044327 expression among strains exhibiting significant differences in leaf width. Based on an assessment of EMS mutant lines harboring a conserved amino acid stop mutation and two non-synonymous mutations in Zm00001d044327 that exhibited a narrow leaf width, these data suggested that Zm00001d044327 is a key regulator of maize leaf width. [ABSTRACT FROM AUTHOR]

• The equations that use the product between L and W are the most suitable for predicting LA. • The linear and power models are the most suitable for estimating the leaf area of sweet potato cultivars;. • The proposed non-destructive method presents high accuracy for four sweet potato cultivars. Many researchers consider the leaf area the most critical parameter for plant growth and physiology studies. Using allometric equations is considered an effective and non-destructive method for estimating the leaf area of plants. The objectives of this study were to construct allometric equations to predict the leaf area of sweet potato cultivars as a function of leaf dimensions and to verify the effectiveness of the allometric equations constructed for each cultivar individually and for the grouped data. Two hundred fifty leaves of the sweet potato cultivars Beauregard, BRS Amélia, BRS Cuia, and Coquinho were collected, and then the length and width of each leaf were measured. Subsequently, the product between leaf length and width and the actual leaf area was calculated. Linear, linear without intercept, power, and exponential regression models were used to construct allometric equations to predict leaf area. The best equations were chosen according to the highest coefficients of determination and correlation, Willmott agreement index, and lowest Akaike information criterion and root mean square error. The equations obtained with the linear models without intercept and power using the length and width of the leaves were the most indicated for predicting the leaf area of sweet potato cultivars. [ABSTRACT FROM AUTHOR]

Background and Aims Leaf area (A) is a crucial indicator of the photosynthetic capacity of plants. The Montgomery equation (ME), which hypothesizes that A is proportional to the product of leaf length (L) and width (W), is a valid tool for non-destructively measuring A for many broadleaved plants. At present, the methods used to compute L and W for the ME can be broadly divided into two kinds: using computer recognition and measuring manually. However, the potential difference in the prediction accuracy using either method has not been thoroughly examined in previous studies. Methods In the present study, we measured 540 Alangium chinense leaves, 489 Liquidambar formosana leaves and 215 Liriodendron  ×  sinoamericanum leaves, utilizing computer recognition and manual measurement methods to determine L and W. The ME was used to fit the data determined by the two methods, and the goodness of fits were compared. The prediction errors of A were analysed by examining the correlations with two leaf symmetry indices (areal ratio of the left side to the right side, and standardized index for bilateral asymmetry), as well as the leaf shape complexity index (the leaf dissection index). Key Results The results indicate that there is a neglectable difference in the estimation of A between the two methods. This further validates that the ME is an effective method for estimating A in broadleaved tree species, including those with lobes. Additionally, leaf shape complexity significantly influenced the estimation of A. Conclusions These results show that the use of computer recognition and manual measurement in the field are both effective and feasible, although the influence of leaf shape complexity should be considered when applying the ME to estimate A in the future. [ABSTRACT FROM AUTHOR]

Plant height and leaf morphology are considered complex agronomy traits; both are significantly related to nutrient utilization, lodging resistance, and photosynthetic efficiency, which ultimately affect biomass and yield. However, the molecular mechanism of leaf morphogenesis is still unclear. WOX is a group of plant-specific transcription factor families that regulate growth and development, cell division, and differentiation in plants. In the present study, we identified and characterized the m-876 mutant in barley (Hordeum vulgare L.), which exhibited an extreme reduction in leaf width and plant height. Using a map-based cloning strategy, the m-876 mutant was narrowed down to an 11.4 Mb genomic interval on the long arm of chromosome 5. By analyzing the gene annotation information and nucleotide sequences, we found that HvWOX3A (HORVU.MOREX.r3.5HG0467090) had a G-to-A substitution at the second exon in the m-876 mutant, resulting in a change of the coding amino acid from Tryptophan to a premature stop codon at the 200th amino acid position. Remarkably, the mutation of the HvWOX3A gene leads to changes in gene expression in the m-876 mutant. Collectively, our results indicate that the loss function of the HORVU.MOREX.r3.5HG0467090 gene might be responsible for the phenotypic variation in barley mutants. [ABSTRACT FROM AUTHOR]

In order to explore the appropriate leaf length, leaf width and leaf weight range of high-quality cured tobacco leaves in Guangyuan and provide data support for the production of high-quality flue-cured tobacco in Guangyuan, 10 tobacco farmers with representative planting levels were selected to take 2 kg samples of X2F, C2F, C3F and B2F from 5 purchase lines in Jiangue County, Guangyuan City, Sichuan Province in 2021. The tobacco leaf quality was evaluated according to different leaf length width and single leaf weight. The results showed as follows; with the increase of leaf length, the contents of total sugar and reducing sugar in X2F, B2F tobacco decreased, and the contents of nicotine and potassium increased with the increase of C3F. The content of total sugar and reducing sugar increased gradually with the increase of leaf width. The content of total sugar in tobacco leaves of X2F and C3F grades increased with the increase of single leaf weight, while the content of potassium decreased. The total appearance quality of X2F increased first and then decreased with the increase of leaf width and single leaf weight. With the increase of leaf length, the total appearance quality of C2F and C3F increased gradually, and the total appearance quality was ranked from high to low as > 75 cm, 65-75 cm,>55-65 cm, ≤55 cm. With the increase of leaf length, leaf width and single leaf weight, the sensory quality scores of C2F, C3F and B2F mainly showed the trend of first increase and then decrease. With the increase of leaf length and width, the scores of C2F and B2F were firstly increased and then decreased. The comprehensive quality of X2F tobacco leaves was better when the leaf length was controlled at >50-60 cm, leaf width at 15-19 cm and single leaf weight at >7-11 g. When the leaf length of C2F was > 55-65 cm, the leaf width was >15-23 cm and the weight of single leaf was >9-13g, the comprehensive quality of C2F tobacco was better. When the leaf length of C3F was >65-75 cm, the leaf width was >15-23 cm and the single leaf weight was >8-12 g, the comprehensive quality of C3F tobacco was better. When the leaf length of B2F was controlled at >55-65 cm, the leaf width was controlled at >15-23 cm, and the single leaf weight was controlled at >9-15 g, the comprehensive quality of B2F tobacco was better. [ABSTRACT FROM AUTHOR]

Maize is an important food and feed crop. Under limited arable land area, the cultivation of high-density-tolerance crops is a key factor in promoting yield improvement. Leaf width and stalk strength are important influences on density tolerance in maize. However, no comprehensive transcriptomic analysis has focused on maize's leaf width and stalk strength formation mechanisms. In this study, comparative transcriptomic analyses demonstrated that significant transcriptome changes occurred regarding leaf width and stalk strength of narrow-leaved and wide-leaved maize inbred lines, with a total of 5001 differentially expressed genes (DEGs) identified. Enrichment analysis showed that phenylpropanoid biosynthesis, starch and sucrose metabolism, phytohormone signaling, amino acid metabolism, and brassinosteroid biosynthesis were significantly correlated with the formation of maize leaf shape and stalk strength and that the genes in these pathways were primarily involved in cell wall formation. Weighted gene co-expression network analysis identified 2 modules significantly correlated with leaf width and stalk strength, from which 11 hub genes were further identified. The 11 leaf and stem development genes in different pathways were validated using qRT-PCR. These findings can provide a theoretical basis for the mechanism of narrow-leaf and high-strength stalk formation in high-density-tolerance maize and contribute to the proposal of a breeding strategy for yield improvement. [ABSTRACT FROM AUTHOR]

Background and Objectives: The importance of rapid, non-destructive, and accurate estimation of leaf area (LA) in agronomic and physiological studies is well known. The need for such estimates of leaf area in particular for leaves with unusual shapes has led to studies relating leaf dimensions and leaf area. However, a search of literature revealed that little information is available for short day onion (Allium cepa L.). The objective of this study was to develop a statistically validated regression model for leaf area prediction from simple non-destructive measurements for onion cultivated in the South of Iran. Materials and Methods: In order to prepare the required plant samples to measure leaf area parameters, an experiment was conducted in the cropping year 2020-2021 in a field of 300 square meters located in Hormozgan province-Rahdad district. The short-day cultivar Takii was used because of its wide planting area in the province. 40 leaves were chosen at random from plants growing in the farm, half were left for validation of the model and the other 20 leaves were subjected to measurement and calibration. The standard method (LICOR LI-3000C) was used for measuring the actual areas of the leaves. Before measuring the leaf area, two main parameters related to leaf length and width were accurately determined for each leaf. To select the best variables and the regression model for estimating leaf area, the fitted simple and multiple linear regression were subjected to the stepwise elimination method. Finally, the accuracy of the selected models was validated using the root mean square error (RMSE) and coefficient of determination (R2 ). Results: All linear models for estimation of leaf area with width (W) and length (L) as well as models including both variables were subjected to regression analysis. The results indicated that leaf length (L) is more appropriate variable for estimating onion leaf area and leaf width (W) was not able to properly describe leaf area. Based on the findings of this research leaf area estimation model with both W and L had the best prediction, with RMSE%=8.64, RMSE=1.76 and R2 =0.91. (Area=0.121 + 0.01537 L2 + 0.3225 L×W). Conclusion: As the understanding of plant growth and development has been increasing, such mathematical models will be very useful tools for the prediction of leaf area for many plants without the use of expensive devices. Thus, the models from the present study will enable researchers of plant growth modeling to predict leaf area non-destructively with the equations developed. [ABSTRACT FROM AUTHOR]

Canopy architecture in cereals plays an important role in determining yield. Leaf width represents one key aspect of this canopy architecture. However, our understanding of leaf width control in cereals remains incomplete. Classical mutagenesis studies in barely identified multiple morphological mutants, including those with differing leaf widths. Of these, we characterized the broad leaf13 (blf13) mutant in detail. Mutant plants form wider leaves due to increased post-initiation growth and cell proliferation. The mutant phenotype perfectly co-segregated with a missense mutation in the HvHNT1 gene which affected a highly conserved region of the encoded protein, orthologous to the rice NARROW LEAF1 (NAL1) protein. Causality of this mutation for the blf13 phenotype is further supported by correlative transcriptomic analyses and protein–protein interaction studies showing that the mutant HvNHT1 protein interacts more strongly with a known interactor than wild-type HvHNT1. The mutant HvHNT1 protein also showed stronger homodimerization compared with wild-type HvHNT1, and homology modelling suggested an additional interaction site between HvHNT1 monomers due to the blf13 mutation. Thus, the blf13 mutation parallels known gain-of-function NAL1 alleles in rice that increase leaf width and grain yield, suggesting that the blf13 mutation may have a similar agronomic potential in barley. [ABSTRACT FROM AUTHOR]

Leaf width is a key determinant of planting density and photosynthetic efficiency. In an effort to determine which genes regulate maize plant leaf width, we performed a genome-wide association study (GWAS) of 1.49 × 106 single nucleotide polymorphisms (SNPs) in 80 sequenced backbone inbred maize lines in Jilin Province, China, based upon phenotypic leaf width data from two years. In total, 14 SNPs were identified as being significantly related to leaf width (p < 0.000001), with these SNPs being located on chromosomes 1, 2, 3, 5, 6, 7, 8, and 9. A total of five candidate genes were identified within a mean linkage disequilibrium (LD) distance of 9.7 kb, with a significant SNP being identified within the Zm00001d044327 candidate gene. RNA was then isolated from 12 different inbred maize lines from this GWAS study cohort and was used to conduct qPCR analyses which revealed significant differences in Zm00001d044327 expression among strains exhibiting significant differences in leaf width. Based on an assessment of EMS mutant lines harboring a conserved amino acid stop mutation and two non-synonymous mutations in Zm00001d044327 that exhibited a narrow leaf width, these data suggested that Zm00001d044327 is a key regulator of maize leaf width.

Plant height and leaf morphology are considered complex agronomy traits; both are significantly related to nutrient utilization, lodging resistance, and photosynthetic efficiency, which ultimately affect biomass and yield. However, the molecular mechanism of leaf morphogenesis is still unclear. WOX is a group of plant-specific transcription factor families that regulate growth and development, cell division, and differentiation in plants. In the present study, we identified and characterized the m-876 mutant in barley (Hordeum vulgare L.), which exhibited an extreme reduction in leaf width and plant height. Using a map-based cloning strategy, the m-876 mutant was narrowed down to an 11.4 Mb genomic interval on the long arm of chromosome 5. By analyzing the gene annotation information and nucleotide sequences, we found that HvWOX3A (HORVU.MOREX.r3.5HG0467090) had a G-to-A substitution at the second exon in the m-876 mutant, resulting in a change of the coding amino acid from Tryptophan to a premature stop codon at the 200th amino acid position. Remarkably, the mutation of the HvWOX3A gene leads to changes in gene expression in the m-876 mutant. Collectively, our results indicate that the loss function of the HORVU.MOREX.r3.5HG0467090 gene might be responsible for the phenotypic variation in barley mutants.

Maize is an important food and feed crop. Under limited arable land area, the cultivation of high-density-tolerance crops is a key factor in promoting yield improvement. Leaf width and stalk strength are important influences on density tolerance in maize. However, no comprehensive transcriptomic analysis has focused on maize’s leaf width and stalk strength formation mechanisms. In this study, comparative transcriptomic analyses demonstrated that significant transcriptome changes occurred regarding leaf width and stalk strength of narrow-leaved and wide-leaved maize inbred lines, with a total of 5001 differentially expressed genes (DEGs) identified. Enrichment analysis showed that phenylpropanoid biosynthesis, starch and sucrose metabolism, phytohormone signaling, amino acid metabolism, and brassinosteroid biosynthesis were significantly correlated with the formation of maize leaf shape and stalk strength and that the genes in these pathways were primarily involved in cell wall formation. Weighted gene co-expression network analysis identified 2 modules significantly correlated with leaf width and stalk strength, from which 11 hub genes were further identified. The 11 leaf and stem development genes in different pathways were validated using qRT-PCR. These findings can provide a theoretical basis for the mechanism of narrow-leaf and high-strength stalk formation in high-density-tolerance maize and contribute to the proposal of a breeding strategy for yield improvement.