Maize Growth Responses to a Humic Product in Iowa Production Fields: An Extensive Approach

Field evaluations of commercial humic products have seldom involved replication across location or year. To evaluate the consistency of humic product efficacy in field conditions, we determined the effects of a humic product on maize (Zea mays L.) growth in high-yielding Midwestern (US) fields through the following two extensive approaches: (i) replicated strip plots in five site—year combinations from 2010 to 2013; and (ii) demonstration strips in 30–35 production fields annually from 2009 to 2011 that covered major areas of Iowa. Mechanized combine measurements of grain yield showed increases of 0.2–0.4 Mg ha–1 (1–4%) with humic product application for all five site—year combinations of the replicated strip plots. Six of 10 humic treatments within the fields responded positively (P < 0.07), and the positive responses of two more treatments approached significance at the benchmark of P = 0.10. In the demonstration strips, maize grain weight in hand-collected samples increased significantly (P < 0.004) with humic product application in each of the three growing seasons, and across all the three seasons by 6.5% (P < 0.001). Grain weight increased numerically for 76 of the 98 demonstration strips. Yield component analysis for both the replicated strip plots and the demonstration strips attributed the yield boosts largely to increased ear length, especially of the shorter ears. Humic product application caused significantly (P < 0.10) greater total leaf area in all eight field treatments at three site—year combinations. Humic product application did not consistently affect nutrient concentrations of the grain or stover or any measured soil property. These results represent among the widest geographic evaluations published on field efficacy of a humic product. They demonstrate the capability of a humic product to improve maize growth in high-yielding conditions.

Leaf surface index as an indicator of moisture responsiveness and drought resistance of winter bread wheat samples

The growth and productivity of drought-prone varieties are strongly influenced by the chlorophyll pigment content and the development of plants’ foliage. The current climate changing, characterized by long no-rain periods followed by short intense rainfalls, is forcing plants to adopt different strategies to cope with drought. The purpose of the current study is to estimate the effect of growing conditions on the indicators of the total leaf area, leaf surface index (LSI) of sowing, the concentration of chlorophylls (Chl) in the leaves and the yield of winter wheat, depending on the value of their moisture supply. There have been established that the leaf surface index change and the preservation of chlorophyll pigment in foliage during the vegetation period is closely related to plants’ drought resistance, soil moisture reserve and a genotype. Under conditions of insufficient moisture supply, the maximum values of the leaf surface index in the heading phase were formed by the varieties ‘Krasa Dona’ (5.99 r.u) and ‘Etyud’ (2.49 r.u.). The highest content of chlorophyll pigment, both in the heading phase and in the flowering phase, was identified in the varieties ‘Krasa Dona’ (3.7; 3.0 mg/100 g of raw material), ‘Etyud’ (3.4; 3.2 mg/100 g of raw material) and ‘Volny Don’ (3.2; 3.0 mg/100 g of raw material), respectively. Acording to the value of productivity, the reliably standard variety ‘Don 107’ has exceeded the varieties ‘Etyud’, ‘Krasa Dona’, ‘Asket’, ‘Volny Don’.

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.

Physiological Response and Proteomics Analysis of Reaumuria soongorica Under Salt Stress

Soil salinity can severely restrict plant growth. Yet Reaumuria soongorica can tolerate salinity well. However, large-scale proteomic studies of this plant’s salinity response have yet to reported. Here, R. soongorica seedlings (4 months old) were used in an experiment where NaCl solutions simulated levels of soil salinity stress. The fresh weight, root/shoot ratio, leaf relative conductivity, proline content, and total leaf area of R. soongorica under CK (0 mM NaCl), low (200 mM NaCl), and high (500 mM NaCl) salt stress were determined. The results showed that the proline content of leaves was negatively correlated with salt concentration. With greater salinity, the plant fresh weight, root/shoot ratio, and total leaf area increased initially but then decreased, and vice-versa for the relative electrical conductivity of leaves. Using iTRAQ proteomic sequencing, 47, 177, 136 differentially expressed proteins (DEPs) were identified in low-salt vs. CK, high-salt vs. control, and high-salt vs. low-salt comparisons, respectively. A total of 72 DEPs were further screened from the groups, of which, 34 DEPs increased and 38 DEPs decreased in abundance. These DEPs are mainly involved in translation, ribosomal structure, and biogenesis. Finally, 21 key DEPs (SCORE value ≥ 60 point) were identified as potential targets for salt tolerance of R. soongolica. By comparing the protein structure of treated vs. CK leaves under salt stress, we revealed the key candidate genes underpinning R. soongolica’s salt tolerance ability. This works provides fresh insight into its physiological adaptation strategy and molecular regulatory network, and a molecular basis enhancing breeding, under salt stress conditions.

Cultivation of Solanum lycopersicum under Glass Coated with Nanosized Upconversion Luminophore

The effect of upconverting luminescent nanoparticles coated on glass on the productivity of Solanum lycopersicum was studied. The cultivation of tomatoes under photoconversion glass led to an increase in plant productivity and an acceleration of plant adaptation to ultraviolet radiation. An increase in the total leaf area and chlorophyll content in the leaves was revealed in plants growing under the photoconversion glass. Plants growing under the photoconversion glass were able to more effectively utilize the absorbed light energy. The results of this study suggest that the spectral changes induced by photoconversion glass can accelerate the adaptation of plants to the appearance of ultraviolet radiation.

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.

Allometry Between Vegetative and Reproductive Traits in Orchids

In flowering plants, inflorescence characteristics influence both seed set and pollen contribution, while inflorescence and peduncle size can be correlated with biomass allocation to reproductive organs. Peduncles also play a role in water and nutrient supply of flowers, and mechanical support. However, it is currently unclear whether inflorescence size is correlated with peduncle size. Here, we tested whether orchids with large diameter peduncles bear more and larger flowers than those with smaller peduncles by analyzing 10 traits of inflorescence, flower, and leaf in 26 species. Peduncle diameters were positively correlated with inflorescence length and total floral area, indicating that species with larger peduncles tended to have larger inflorescences and larger flowers. We also found strongly positive correlation between inflorescence length and leaf area, and between total floral area and total leaf area, which suggested that reproductive organs may be allometrically coordinated with vegetative organs. However, neither flower number nor floral dry mass per unit area were correlated with leaf number or leaf dry mass per unit area, implying that the function between leaf and flower was uncoupled. Our findings provided a new insight for understanding the evolution of orchids, and for horticulturalists interested in improving floral and inflorescence traits in orchids.

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.