Frontiers in Plant Science最新文献

Poor nutrient use efficiency (NUE) and water use efficiency (WUE) is a predominantly faced problem in semi-arid regions that limit the crop production. This problem can be addressed with the application of zeolite that is a naturally available mineral with very high cation exchange and water holding capacity, which aids in improving NUE and WUE. Moreover, zeolites are safe for the environment and living organisms, and their use in agriculture results in improving physical and chemical properties of soil. Yet, its study is very limited in semi-arid regions of India. Thus, a study was conducted with locally available zeolite at CRIDA, Hyderabad. Zeolite was further characterized using X-ray diffraction (XRD) and SEM, as the type of zeolite collected is unknown from local market. The results of XRD and SEM revealed that the zeolite collected was mordenite zeolite. Our study includes laboratory and pot experiment where laboratory includes sorption and leaching column study to evaluate the zeolite capacity to hold and release the nutrients especially NH₄ ⁺, P, and K. In this study, the adsorption behaviour of the natural mordenite was examined, and it was found that the maximum adsorption capacity for NH₄ ⁺, P, and K were estimated as 10.6, 1.08, and 2.15 mg g^-1, respectively, suggesting the zeolite has good affinity for N. Furthermore, the column study revealed that there was 15.4% reduction in NH₄ ⁺-N loss with 10 tonnes zeolite ha^-1 + N @ 100 kg ha^-1 as compared to N alone, while the reduction was 39.6% with 10 tonnes zeolite ha^-1 + N @ 500 kg ha^-1 compared to N alone, suggesting that the zeolite could control the release of N as compared to the sole application of N, which was supplied through urea. In addition, pot experiment was carried out with three levels of fertiliser rates, four levels of zeolite, and two levels of moisture in randomised complete block design with three replications to evaluate the changes in soil available nutrients and their uptake in tomato. Results revealed that there was a significant positive impact on yield, water use efficiency, nutrient (N, P, and K) uptake, and soil available nutrients. Highest soil available N, P, and K, crop uptake, and yield were observed due to zeolite application @ 200 kg ha^-1 along with 100% recommended dose of fertilization in Alfisols. Thus, zeolite application along with chemical fertilisers can improve the nutrient availability by reducing the leaching losses and improving nutrient use efficiency.

Phenotypic traits like plant height are crucial in assessing plant growth and physiological performance. Manual plant height measurement is labor and time-intensive, low throughput, and error-prone. Hence, aerial phenotyping using aerial imagery-based sensors combined with image processing technique is quickly emerging as a more effective alternative to estimate plant height and other morphophysiological parameters. Studies have demonstrated the effectiveness of both RGB and LiDAR images in estimating plant height in several crops. However, there is limited information on their comparison, especially in soybean (Glycine max [L.] Merr.). As a result, there is not enough information to decide on the appropriate sensor for plant height estimation in soybean. Hence, the study was conducted to identify the most effective sensor for high throughput aerial phenotyping to estimate plant height in soybean. Aerial images were collected in a field experiment at multiple time points during soybean growing season using an Unmanned Aerial Vehicle (UAV or drone) equipped with RGB and LiDAR sensors. Our method established the relationship between manually measured plant height and the height obtained from aerial platforms. We found that the LiDAR sensor had a better performance (R² = 0.83) than the RGB camera (R² = 0.53) when compared with ground reference height during pod growth and seed filling stages. However, RGB showed more reliability in estimating plant height at physiological maturity when the LiDAR could not capture an accurate plant height measurement. The results from this study contribute to identifying ideal aerial phenotyping sensors to estimate plant height in soybean during different growth stages.

To explore the flavor related regulatory mechanisms of fresh Corylus heterophylla × Corylus avellana, a joint analysis of metabolome and transcriptome were utilized to compare the two typical C. heterophylla × C. avellana varieties with different flavors ('yuzhui' and 'pingou21') in this paper. The results showed that the genes including E2.4.1.67-1, E2.4.1.67-2, SUS-1, SUS-2, SUS-4, SUS-5, SUS-7, SUS-8, SUS-9, UGP2-2 were identified as responsible for regulating the levels of stachyose, manninotriose and raffinose in hazelnuts. CS and OGDH were deemed as the genes involved in the citric acid cycle, which was a central metabolic pathway that generated energy through the oxidation of carbohydrates, fats and proteins in hazelnuts. The genes trpD, ALDO, PK-1, PK-2, ilvH, argE-1, argE-4, argE-5, argD, PDAH, GLTI were regarded as involved in the biosynthesis of various amino acids like tryptophan, valine, alanine, and arginine. These amino acids determined the taste of C. heterophylla × C. avellana and were important precursors of other flavor-related compounds. The genes LOX2S-2, LOX2S-3, LOX2S-4 and LCAT3 were viewed as involved in the regulation of lipid biosynthesis, specifically involving 13(S)-HPODE, 9,10,13-trihome and 13(S)-HOTrE in C. heterophylla × C. avellana. These findings highlight the significance of genes and metabolites and internal regulatory mechanisms in shaping the flavor of fresh C. heterophylla × C. avellana cultivated in temperate continents. This study provides the theoretical basis for breeding excellent food functional hazelnut varieties.

Benzylisoquinoline alkaloids (BIAs) are a prominent class of plant metabolites with significant pharmaceutical and industrial significance that have garnered substantial attention from researchers worldwide. BIAs exhibit several pharmacological activities and have been used extensively. Examples include analgesics such as morphine, tetrahydropalmatine, antimicrobials such as berberine, and antineoplastic agents including cepharanthine. Most BIAs are derived and isolated from medicinal plants; however, these plants are predominantly wild resources that are scarce. Their high environmental impact, slow growth rate, scarcity of resources, and expensive direct extraction costs pose a significant challenge. Certain BIAs are present in trace amounts in medicinal plants; moreover, they have complex chemical structures and unstable properties. Designing chemical synthesis routes and processes is challenging. Thus, a major obstacle in developing and utilizing these natural products in the pharmaceutical industry lies in their low abundance in nature. Consequently, the limited supply of these molecules fails to meet high research and market demands. In recent years, biosynthesis approaches have emerged as a novel and efficient method to obtain BIAs. In this review, recent progress in the field of enzymes related to the elucidation of biosynthetic pathways and the biosynthesis of BIAs are discussed, and future perspectives for designing viable strategies for their targeted manipulation are presented.

Introduction: Soil chemical properties and bacterial communities play key roles in shaping tea plant nutrient status and quality. While the relationships between soil bacterial communities and plant nutrient status have been investigated, the specific role by which soil bacterial communities interacted with soil properties to influence tea plant nutrients and quality remained underexplored.

Methods: In this study, different soil types were collected from tea gardens and designated as soil A (pH 3.41), soil B (pH 3.75), soil C (pH 4.16), soil D (pH 4.17) and soil E (pH 5.56) based on the initial soil pH. We conducted pot cultivation of tea plant 'Yabukita' to investigate how soil chemical factors affect bacterial communities and their influences on the nutrient status and quality of tea plants, and finally explored the complex relationships between soil bacterial features and tea quality.

Results and discussion: The results showed that soil bacterial α-diversity was higher level in soils D and E, with distinct β-diversity patterns separating higher pH soils (D and E) from lower pH soils (A, B, and C). The dominant amplicon sequence variants (ASVs) in soils were Proteobacteria (28.12%), Actinobacteriota (25.65%), Firmicutes (9.99%) at phylum level, and Acidothermaceae (7.24%), Solirubrobacteraceae (4.85%), and Acetobacteraceae (4.50%) at family level. Soil pH, exchangeable Mg²⁺, and Ca²⁺ were identified as key factors shaping bacterial community composition and positively correlated with bacterial diversity. Differentially abundant ASVs (DAAs) among all soils were also identified including the phylum Firmicutes and families such as Paenibacillaceae, Alicyclobacillaceae, JG36-TzT-191, KF-JG30-C25, and Acidobacteriaceae_subgroup1. Besides, the nutrient content of tea new leaves varied significantly among soil types and harvests. Combined with Mantel-test association analysis, soil chemical properties and soil bacterial communities were jointly correlated with the contents of total nitrogen, potassium, calcium, aluminum, magnesium, free amino acids, and caffeine in tea new leaves. These findings highlight the dynamic interactions between soil properties, bacterial communities, and tea nutrients, emphasizing the importance of optimizing soil health and bacterial networks to improve tea quality.

Extracting the navigation line of crop seedlings is significant for achieving autonomous visual navigation of smart agricultural machinery. Nevertheless, in field management of crop seedlings, numerous available studies involving navigation line extraction mainly focused on specific growth stages of specific crop seedlings so far, lacking a generalizable algorithm for addressing challenges under complex cross-growth-stage seedling conditions. In response to such challenges, we proposed a generalizable navigation line extraction algorithm using classical image processing technologies. First, image preprocessing is performed to enhance the image quality and extract distinct crop regions. Redundant pixels can be eliminated by opening operation and eight-connected component filtering. Then, optimal region detection is applied to identify the fitting area. The optimal pixels of plantation rows are selected by cluster-centerline distance comparison and sigmoid thresholding. Ultimately, the navigation line is extracted by linear fitting, representing the autonomous vehicle's optimal path. An assessment was conducted on a sugarcane dataset. Meanwhile, the generalization capacity of the proposed algorithm has been further verified on corn and rice datasets. Experimental results showed that for seedlings at different growth stages and diverse field environments, the mean error angle (MEA) ranges from 0.844° to 2.96°, the root mean square error (RMSE) ranges from 1.249° to 4.65°, and the mean relative error (MRE) ranges from 1.008% to 3.47%. The proposed algorithm exhibits high accuracy, robustness, and generalization. This study breaks through the shortcomings of traditional visual navigation line extraction, offering a theoretical foundation for classical image-processing-based visual navigation.

This study aimed to uncover salt-tolerant eggplant (Solanum melongena L.) genotypes and accessions. Crop wild relatives (S. macrocarpon L., S. linnaeanum, S. incanum L., S. insanum L., S. sisymbriifolium Lam.), commercial varieties (Topan374, Kemer, Amadeo, Faselis, Bildircin), and local genotypes (TB, BB, MK, AH) were investigated under 150 mM NaCl stress. The experiment was set in a completely randomized block design with three replications. Morphological and biochemical parameters were studied to distinguish salt-tolerant genotypes. Wild relatives have species-specific growth features; thus, the salt tolerance levels of morphologic features such as plant height and leaf area were found inappropriate to be compared. In eggplant, Na⁺ is a majorly harmful ion and there is a negative correlation between leaf Na⁺ content and plant tolerance index. The low Na⁺ concentration in roots of BB and S. linnaeanum caused high K⁺ and Ca²⁺ concentrations in their leaves. A plant with high proline accumulation displays greater tolerance under stress conditions. The proline content of S. linnaeanum, S. incanum L., and MK was analyzed to be higher than the others. Additionally, the lowest malondialdehyde (MDA) increases were observed in S. linnaeanum, TB, and S. incanum L. Moreover, positive correlations were spotted between 0-5 scale values and MDA and Na⁺ level in shoots by correlation analysis. Strong correlations between proline accumulation-S. linnaeanum and MDA accumulation-AH were revealed by principal component analysis (PCA). In terms of results, the most salt-tolerant, S. linnaeanum, S. incanum L., BB, and MK, will be employed in future breeding studies to improve salt-tolerant inbred lines and varieties through interspecific hybridization.

Introduction: Hemipteran gall vascular traits result from the access, piercing, and sucking of the inducer mouth parts directly in the xylem and phloem conductive cells. Herein, our focus relies on mapping the features of phloem cells in the proximal, median, and distal regions of Malus pumila stem galls and adjacent galled stems.

Methods: Phloem cells were dissociated from gall fragments, the stem portions above and below the galls, and the proximal and distal regions of M. pumila stem galls. were measured. The comparison of the higher length and diameter of the sieve tube elements (STE) was evaluated considering the priority of nutrient flow to gall portions.

Results: In the M. pumila - E. lanigerum system, there were no significant differences in the dimensions of the STE in the galls compared with those of the stem portions above and below the galls.

Discussion: At the cytological level, the callose deposited in gall STE and the decrease in the cell lumen area in the stem portion above the gall due to thickened nacreous cell walls have implications for nutrient flow. Peculiarly, the smaller sieve pores in the sieve plates of the STE located in the galls and stem portions above and below them and the deposition of P-protein in the stem portions below the galls limit the bidirectional transport of nutrients, benefiting the transport of photoassimilates to the gall proximal region and reducing the vigor of apple tree stems.

The microfilament cytoskeleton, formed by the process of actin polymerization, serves not only to support the morphology of the cell, but also to regulate a number of cellular activities. Actin-depolymerizing factors (ADFs) represent a significant class of actin-binding proteins that regulate the dynamic alterations in the microfilament framework, thereby playing a pivotal role in plant growth and development. Additionally, they are instrumental in modulating stress responses in plants. The ADF gene family has been explored in various plants, but there was a paucity of knowledge regarding the ADF gene family in alfalfa (Medicago sativa), which is one of the most significant leguminous forage crops globally. In this study, a total of nine ADF genes (designated MsADF1 through MsADF9) were identified in the alfalfa genome and mapped to five different chromosomes. A phylogenetic analysis indicated that the MsADF genes could be classified into four distinct groups, with members within the same group exhibiting comparable gene structures and conserved motifs. The analysis of the Ka/Ks ratios indicated that the MsADF genes underwent purity-based selection during its evolutionary expansion. The promoter region of these genes was found to contain multiple cis-acting elements related to hormone responses, defence, and stress, indicating that they may respond to a variety of developmental and environmental stimuli. Gene expression profiles analyzed by RT-qPCR experiments demonstrated that MsADF genes exhibited distinct expression patterns among different organs. Furthermore, the majority of MsADF genes were induced by salt and drought stress by more than two-fold, with MsADF1, 2/3, 6, and 9 being highly induced, suggesting their critical role in resistance to abiotic stress. These results provide comprehensive information on the MsADF gene family in alfalfa and lay a solid foundation for elucidating their biological function.

A comprehensive understanding of the genetics of resistance is essential for developing an effective breeding strategy to create germplasm resistant to Fusarium Ear Rot. This study aimed to determine the general combining ability (GCA), specific combining ability (SCA), and heritability of resistance to infection by Fusarium verticillioides in tropical maize. Using the North Carolina II mating design, six inbred lines as females and seven as males were crossed to produce 42 hybrids, which were evaluated across five environments using artificial inoculation. At harvest, the hybrids were scored for Fusarium Ear Rot (FER) infection using a 1-9 severity scale. Significant GCA effects for the parents and SCA effects for the hybrids were observed. The narrow-sense heritability estimate was 0.22, while the broad-sense heritability was 0.73, and the additive genetic effects, as represented by GCA (m+f), were more significant than non-additive effects. The inbred parents JPS25-13, JPS26-125, JPS26-86, JPS25-11, JPS25-5, JPS25-7, and JPS25-9 were identified as the best general combiners for FER resistance. These lines, with favorable general combining ability effects for resistance to Fusarium verticillioides, are strong candidates for breeding resistant varieties.