Early-Stage Brown Spot Disease Recognition in Paddy Using Image Processing and Deep Learning Techniques

India is an agricultural country. Paddy is the main crop here on which the livelihood of millions of people depends. Brown spot disease caused by fungus is the most predominant infection that appears as oval and round lesions on the paddy leaves. If not addressed on time, it might result in serious crop loss. Pesticide use for plant disease treatment should be limited because it raises costs and pollutes the environment. Usage of pesticide and crop loss both can be minimized if we recognize the disease in a timely manner. Our aim is to develop a simple, fast, and effective deep learning structure for early-stage brown spot disease detection by utilizing infection severity estimation using image processing techniques. The suggested approach consists of two phases. In the first phase, the brown spot infected leaf image dataset is partitioned into two sets named as early-stage brown spot and developed stage brown spot. This partition is done on the basis of calculated infection severity. Infection severity is computed as a ratio of infected pixel count to total leaf pixel count. Total leaf pixel counts are determined by segmenting the leaf region from the background image using Otsu's thresholding technique. Infected pixel counts are determined by segmenting infected regions from leaf regions using Triangle thresholding segmentation. In the second phase, a fully connected CNN architecture is built for automatic feature extraction and classification. The CNN-based classification model is trained and validated using early-stage brown spot, developed stage brown spot, and healthy leaves images of rice plants. Early-stage brown spot and developed stage brown spot images used in training and validation are the same images that are obtained in phase 1. The experimental analysis shows that the proposed fully connected CNN-based early-stage brown spot disease recognition model is an effective approach. The classification accuracy of the suggested model is found to be 99.20%. The result of the suggested method is compared with those existing CNN-based disease recognition and classification methods that have used leaf images to recognize the diseases. It is observed that the performance of our method is significantly better than compared methods.

Morphological and anatomical features of winter rye leaves development

Differences of rye varieties in the length of lamina and sheath 1 - 6 from spike of the lamina and leaf sheath, width and area of the lamina were shown. The highest values of the studied leaf parameters were peculiar to the alien varieties of winter rye. It was found that foreign varieties were characterized by a smaller proportion of the plate area of the three upper leaves and a larger proportion for the 4th and 5th leaves (in % of the total leaf plate area). A characteristic feature of the laminae of the upper two leaves of winter rye is the absence of trichomes, instead of them there are spines 12 µm long, which are located above the conductive bundles on the adaxial side of the lamina. Stomata were located on both sides of the leaf, but there were more of them on the adaxial side of the lamina, where they were arranged in one or two rows on the flanks of the conductive bundles. Strong sclerification of conductive bundles was noted. In the most developed conducting bundles, sclerenchyma fibers were observed on both sides of the leaf lamina. The presence of stomata at the leaf sheath on both adaxial and abaxial sides is revealed. It was shown that the contribution of each leaf of upper and middle phytomeres to the total leaf area of winter rye varieties under study is different, which is important to consider when assessing their importance in the photosynthetic potential of plants.

Growth and Physiological Responses of Four Plant Species to Different Sources of Particulate Matter

Background and objective: Particulate matter (PM) has a serious impact on health. Recently, studies are conducted to reduce PM in an environmentally friendly way using plants. This study investigated the physiological responses of plants and their ability to remove PM by continuously spraying different PM sources (loam, fly ash, carbon black) to four native plant species, such as Iris sanguinea, Pteris multifida, Vitis coignetiae, and Viburnum odoratissimum var. awabuki. Methods: The four plant species were randomly placed in four chambers, and 0.1 g of different PM was injected into each chamber twice a week. We measured chlorophyll, carotenoid, chlorophyll fluorescence (Fv/Fm), total leaf area, amount of leaf wax, PM10 (sPM10) and PM2.5 (sPM2.5) on the leaf surface, and PM10 (wPM10) and PM2.5 (wPM2.5) on the wax layer. Results: For I. sanguinea and V. coignetiae, the sources of PM did not affect the growth response. P. multifida showed high chlorophyll a, b, total chlorophyll, and carotenoid content in carbon black as well as high Fv/Fm and total leaf area, thereby proving that carbon black helped plant growth. By PM sources, sPM10 showed a significant difference in three plant species, sPM2.5 in two plant species, and wPM10 in one plant species, indicating that sPM10 was most affected by PM sources. Conclusion: Carbon black increased the leaf area by affecting the growth of P. multifida. This plant can be effectively used for PM reduction by increasing the adsorption area. I. sanguinea and V. coignetiae can be used as economical landscaping plants since they can grow regardless of PM sources.

Evaluation of the Agromorphological Determinants of the Spread of the Bacterial Disease in Orchards of the Main Mango-Producing Regions in Côte d'Ivoire

The use of agroecological practices for the management of phytosanitary problems has become a major issue in the context of sustainable development. It is with this in mind that this study was initiated in the regions of Bagoué, Poro and Tchologo. This study consisted of investigating the determinants likely to promote the spread of the bacterial disease in 720 mango trees of the Kent variety distributed in 20 orchards in the regions of Poro, Tchologo and Bagoué. During this study, the incidence and severity of bacterial disease on leaves and fruits (IsFe, IsFr, IcFe, IcFr) as well as agromorphological parameters such as East-West and North-South spans, total leaf area, fruit load, trunk circumference, total height and number of main branches (En EO and NS, SFT, ChFr, CirTr, HaTr and RamP) were measured. The performance of the pearson correlation test revealed that spans (N-S and E-O), HaTr, SFT and ChFr are the 4 agromorphological determinants that promote the spread of bacteriosis in orchards of the three (3) regions. The synthesis of the results of the ACP and the CAH supplemented by a multivariate analysis (MANOVA) made it possible to structure the mango orchards into three (3) homogeneous groups. Group 1 orchards (VB4, VB8, VS1, VF5, VK1, VB7, VF2 and VK2) expressed the lowest severity indices and the incidence of bacteriosis on the leaves (respectively 15.21 ± 8.87% ; 12.21 ± 6.54%) and fruits (respectively 13.11 ± 4.75%; 10.40 ± 2.93%). These orchards featured mango trees with medium trunk circumferences (99.14 ± 17.24 cm), medium trunk heights (145.29 ± 7.24 cm) and smallest spans (6.85 ± 1, 13 m for the NS span and 6.79 ± 1.18 m for the EO span) and total leaf area (15.61 ± 0.06 cm). These results could help develop an agroecological control strategy for the sustainable management of bacterial disease.

Plant growth and phytoactive alkaloid synthesis in Mitragyna speciosa (kratom) in response to varying radiance

The dose-dependent consumptive effect of kratom and its potential application as an alternative source of medicine to mitigate opioid withdrawal symptoms has brought considerable attention to this plant. Increased interest in the application and use of kratom has emerged globally, including North America. Although the chemistry and pharmacology of major kratom alkaloids, mitragynine and 7-hydroxymitragynine, are well documented, foundational information on the impact of plant production environment on growth and kratom alkaloids synthesis is unavailable. To directly address this need, kratom plant growth, leaf chlorophyll content, and alkaloid concentration were evaluated under three lighting conditions: outdoor full sun, greenhouse unshaded, and greenhouse shaded. Nine kratom alkaloids were quantified using an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method. Contents of six alkaloids to include: mitragynine, speciogynine, speciociliatine, mitraphylline, coynantheidine, and isocorynantheidine were not significantly impacted by lighting conditions, whereas 7-hydroxymitragynine was below the lower limit of quantification across all treatments. However, paynantheine concentration per leaf dry mass was increased by 40% and corynoxine was increased by 111% when grown under shade conditions in a greenhouse compared to outdoor full sun. Additionally, total alkaloid yield per plant was maximized when plants were under such conditions. Greenhouse cultivation generally promoted height and width extension, leaf number, leaf area, average leaf size, and total leaf dry mass, compared to outdoor full sun condition. Rapid, non-destructive chlorophyll evaluation correlated well (r2 = 0.68) with extracted chlorophyll concentrations. Given these findings, production efforts where low-light conditions can be implemented are likely to maximize plant biomass and total leaf alkaloid production.

Lesser-known ethnic leafy vegetables Talinum paniculatum grown at tropical ecosystem: Morphological traits and non-destructive estimation of total leaf area per branch

Lakitan B, Kartika K, Widuri LI, Siaga E, Fadilah LN. 2021. Lesser-known ethnic leafy vegetables Talinum paniculatum grown at tropical ecosystem: Morphological traits and non-destructive estimation of total leaf area per branch. Biodiversitas 22: 4487-4495. Talinum paniculatum known as Java ginseng is an ethnic vegetable in Indonesia that has also been utilized as a medical plant. Young leaves are the primary economic part of T. paniculatum, which can be eaten fresh or cooked. This study was focused on characterizing morphological traits of T. panicultaum and developing a non-destructive yet accurate and reliable model for predicting total area per leaf cluster on each elongated branch per flush growth cycle. The non-destructive approach allows frequent and timely measurements. In addition, the developed model can be used as guidance for deciding the time to harvest for optimum yield. Results indicated that T. paniculatum flourished rapidly under wet tropical conditions, especially if they were propagated using stem cuttings. The plants produced more than 50 branches and more than 800 leaves, or on average produced more than 15 leaves per branch at the age of nine weeks after planting (WAP). The zero-intercept linear model using a combination of two traits of length x width (LW) as a predictor was accurate and reliable for predicting a single leaf area (R2 = 0.997). Meanwhile, the estimation of total area per leaf cluster was more accurate if three traits, i.e., number of leaves, the longest leaf, and the widest leaf in each cluster were used as predictors with the zero-intercept linear regression model (R2 = 0.984). However, the use of a single trait of length (L) and width (W) of the largest leaf within each cluster as a predictor in the power regression model exhibited moderately accurate prediction at the R2 = 0.883 and 0.724, respectively.

Determining relevant traits for selecting landrace accessions of Phaseolus lunatus L. for insect resistance

Plant-insect interactions are a determining factor for sustainable crop production. Although plants can resist or tolerate herbivorous insects to varying degrees, even with the use of pesticides, insects can reduce plant net productivity by as much as 20%, so sustainable strategies for pest control with less dependence on chemicals are needed. Selecting plants with optimal resistance and photosynthetic traits can help minimize damage and maintain productivity. Here, 27 landrace accessions of lima beans, Phaseolus lunatus L., from the Yucatan Peninsula were evaluated in the field for morphological resistance traits, photosynthetic characteristics, insect damage and seed yield. Variation was found in physical leaf traits (number, area, and dry mass of leaves; trichome density, specific leaf thickness and hardness) and in physiological traits (photosynthetic rate, stomatal conductance, intercellular carbon, water-use efficiency, and transpiration). Five accessions (JMC1325, JMC1288, JMC1339, JMC1208 and JMC1264) had the lowest index for cumulative damage with the highest seed yield, although RDA analysis uncovered two accessions (JMC1339, JMC1288) with strong positive association of seed yield and the cumulative damage index with leaf production, specific leaf area (SLA) and total leaf area. Leaf traits, including SLA and total leaf area are important drivers for optimizing seed yield. This study identified 12 important morphological and physiological leaf traits for selecting landrace accessions of P. lunatus for high yields (regardless of damage level) to achieve sustainable, environmentally safe crop production.

EFEITO DO TAMANHO DAS SEMENTES SOBRE A EMERGÊNCIA E MORFOFISIOLOGIA DE MUDAS DE MAMA CADELA

O objetivo deste estudo foi avaliar a emergência de plântulas e a morfofisiologia de mudas de mama-cadela (Brosimum gaudichaudii Trécul) produzidas a partir de sementes de diferentes tamanhos. Foram determinadas a porcentagem de emergência de plântulas e as características morfofisiológicas das mudas (altura, diâmetro do colo, índice de robustez, espessura foliar, índice de clorofila, biomassa seca, massa foliar específica - MFE e área foliar total). A emergência iniciou-se após 21 dias da semeadura e atingiu, ao final do experimento, 84% para as sementes pequenas, valor inferior ao das sementes médias e grandes (94 e 90%, respectivamente). Em 60 dias, as mudas apresentavam, em média, 2,53 mm de diâmetro e 12,81 cm de altura. Nos primeiros 30 dias, as mudas formadas a partir de sementes pequenas tinham alturas menores que as demais. O tamanho das sementes não afetou o diâmetro do colo e a espessura das folhas durante o crescimento inicial das mudas, assim como para os parâmetros morfofisiológicos estudados. Ao longo de 120 dias, houve aumento do conteúdo de clorofilas, biomassa seca, área foliar total, exceto para a MFE. O tamanho das sementes afeta a emergência e a altura das mudas de mama-cadela após 30 dias após a emergência. Palavras-chave: Brosimum gaudichaudii; Cerrado; crescimento inicial. Effect of seed size on emergence and mophophysiology of mama-cadela seedlings ABSTRACT: The objective of this study was to evaluate the seedling emergence and morphophysiology of mama-cadela (Brosimum gaudichaudii Trécul) seedlings produced from seeds of different sizes. Seedling emergence percentage and seedling morphophysiological characteristics (height, diameter, slenderness index, leaf thickness, chlorophyll index, dry matter, specific leaf mass - MFE and total leaf area) were determined. The emergence started after 21 days of sowing and reached, at the end of the experiment, 84% for small seeds, lower than the average and large seeds (94 and 90%, respectively). In 60 days, the seedlings had, on average, 2.53 mm in diameter and 12.81 cm in height. In the first 30 days, seedlings formed from small seeds had shorter heights than the others. The seeds size did not affect the diameter and the leaves thickness during the initial growth of the seedlings, as well as for the morphophysiological parameters studied. Over the 120 days, there was an increase in the content of chlorophylls, dry matter, total leaf area, except for MFE. The seeds size affects the emergence and the height at 30 days after mama-cadela seedlings emergence. Keywords: Brosimum gaudichaudii; Brazilian savanna; initial growth.

A direct comparison of ecological theories for predicting the relationship between plant traits and growth

Despite long-standing theory for classifying plant ecological strategies, limited data directly links organismal traits to whole-plant growth. We compared trait-growth relationships based on three prominent theories: growth analysis, Grime’s CSR triangle, and the leaf economics spectrum (LES). Under these schemes, growth is hypothesized to be predicted by traits related to biomass investments, leaf structure or gas exchange, respectively. In phylogenetic analyses of 30 diverse milkweeds (Asclepias spp.) and 21 morphological and ecophysiological traits, growth rate varied 50-fold and was best predicted by growth analysis and CSR traits, as well as total leaf area and plant height. Despite two LES traits correlating with growth, they contradicted predictions and leaf traits did not scale with root and stem characteristics. Thus, although combining leaf traits and whole-plant allocation best predicts growth, when destructive measures are not feasible, we suggest total leaf area and plant height, or easy-to-measure traits associated with the CSR classification.

Biomass Allocation and Root Characteristics of Early-Stage Poplars (Populus spp.) for Assessing Their Water-Deficit Response During SRC Establishment

Early above- and belowground biomass fractionation, root diameter composition and allocation of cumulated fine root length per total leaf area of Populus clones have been measured for a pre-assessment of the risk for plantation establishment during spring drought conditions. Four clones of Populus × euramericana, and one P. nigra × P. maximowiczii clone (cv. Max 3), were planted in sandy mix substrate and were exposed to one normal and one deficit watering regime over 65-day greenhouse experiments conducted during early summer. The P. × euramericana hybrids showed plasticity of their root biomass fractions. Although clone Max 3 was among the productive clones, even under deficit watering, it was not able to respond plastically to deficit watering. It showed no increase in the root biomass fraction and no increase in the ratio of cumulated fine root length per total leaf area. Therefore, the clone Max 3 should not be planted under high risk for spring drought. Planting the investigated P. × euramericana clones under water deficit likely involves a lower risk, but clone differences within this group must be considered. It can be concluded that the water deficit response of biomass allocation to roots and of the ratio of fine root length per unit leaf area is suitable traits to improve drought risk assessments that are based on yield response of poplar clones to drought. Percent plant loss data and the yield at the end of the first SRC rotation will be suitable to verify the present greenhouse assessment.