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The rice root-knot nematode, Meloidogyne graminicola, is the major bottleneck in aerobic and direct-seeded rice cultivation. Host plant resistance is an environmentally-friendly and cost-effective approach to mitigate damage caused by M. graminicola. Considering the limited availability of genetic resources in Asian rice (Oryza sativa) cultivars, exploration of novel sources of resistance to M. graminicola is necessary. In the present study, we screened 192 diverse wild rice accessions from nine species (Oryza longistaminata, O. barthii, O. glaberrima, O. meridionalis, O. nivara, O. punctata, O. officinalis, O. glumaepatula and O. rufipogon) to identify sources of resistance to M. graminicola. Based on gall number and multiplication factor, two immune and 25 resistant accessions were identified. ‘Pusa Basmati 1121’ and ‘W-27-1’ displayed the highest number of galls per root system and multiplication factor, whereas ‘NW-1’ and ‘NW-17’ had the lowest. Further examination of nematode development suggested that M. graminicola penetrated less often into highly resistant varieties, and, if they penetrated, the juveniles failed to develop into females. Multi-variate analysis was used to investigate the diversity among the wild rice accession for M. graminicola resistance. Analyses showed that the 192 wild accessions of rice could be divided into six clusters based upon their resistance levels. Thirty-four wild accessions exhibited high resistance to M. graminicola, while most accessions showed susceptibility. Analysis of 49 resistant accessions in soil assay correlated very strongly with the identical accessions in ‘PF-127’ assay using the same parameters, indicating the high reproducibility of ‘PF-127’-based assay. The resistant accessions identified in the current study would be a useful resource for studying genetics and the mechanism of resistance to M. graminicola. [ABSTRACT FROM AUTHOR]

[Objective]To understand the drought tolerance of different Phalaenopsis species, to explore the mechanism of drought tolerance of Phalaenopsis, and to provide theoretical support for domestic breeding and introduction of Phalaenopsis and water-saving related applications in production. [Method] Eight different varieties of Phalaenopsis were selected and treated with natural water loss method. On the 20th day of treatment, the relevant indexes of the control group and the treatment group were measured respectively, including fresh weight of the above- ground part, fresh weight of the underground part, dry weight of the above-ground part, dry weight of the underground part, chlorophyll content and other indexes. [ Result] The wilting leaf ratio of ‘ radiant’ was 0. 42, which was the lowest among the 8 varieties. Aboveground fresh weight, aboveground dry weight, aboveground dry weight to aboveground fresh weight ratio and underground dry weight to underground fresh weight ratio were all greater than 1, and the underground fresh weight stress index of ‘red agate’ was 0. 35, along with the aboveground fresh weight, aboveground dry weight and chlorophyll content stress index were much lower than the other 7 varieties. [Conclusion] Under the same drought stress, ‘Radiant’ showed better drought resistance than other varieties, ‘red agate’ showed worse drought resistance. [ABSTRACT FROM AUTHOR]

Blast disease has been one of the most serious threats to rice production. However, the conventional evaluation of rice blast resistance cannot fully meet the large-scale production in recent years. In this study, an efficient evaluation was proposed for rice neck blast resistance via combining unmanned aerial vehicle (UAV) low-altitude remote sensing with the YOLOv7 model. 2 565 images of rice neck blast were collected using UAV and then divided into small-sized images (≤ 1240×1240 pixels) in the annotated area. The small-sized images were further subjected to a random combination of five operations, including rotation, scaling, translation, cropping, and changing contrast. The images with low resolution were removed after data cleaning. Finally, the dataset size was expanded with better diversity. The squeeze extinction attention and deformable convolution were introduced into the YOLOv7 model, in order to capture the fine-grain features of the rice neck blast disease spot. YOLOv7_Neckblast model was established for the rice neck blast detection. The number of affected ears was obtained for 15 rice varieties. The incidence rate was calculated for the disease grade of rice neck blast. Among them, 4, 4, 3, 5, 7, and 9 rice varieties of grades 1, 3, 5, and 7, as well as 9, 2, and 2 were assessed by YOLOv7_Neckblast, respectively. At the intersection over the union (IoU) threshold of 0.5, the mean average precision (mAP) of YOLOv7_Neckblast for rice neck blast was 66.4%, which was 4.0, 6.4, and 5.8 percentage points higher than that of the original YOLOv7, FCOS (fully convolutional one-stage object detection), and RetinaNet models, respectively. The recall rate was 75%, which was 4.0, 8.0, and 22.0 percentage points higher than those of the three models, respectively. The F1 score was 71%, which was 4.0, 5.0, and 12.0 percentage points higher than those of the three models, respectively. The training YOLOv7_Neckblast was relatively stable with the low floating-point operations per second (FLOP) under the same training conditions. The loss values remained stable with about 0.019 and 0.020 at the end of training, which was lower than those of FCOS and RetinaNet models. Furthermore, the molecular-assisted marker selection (MAS) showed that the contribution of the Pit and Pib genes to the resistance to the neck blast was 100.0% and 57.14%, respectively. The rice varieties carrying the Pit and Pib genes also exhibited a stronger resistance to disease. In addition, YOLOv7_Neckblast achieved an average accuracy of 86.67% in evaluating 15 rice varieties' resistance, compared with the actual resistance level. The low-altitude UAV remote sensing coupled with machine learning can be used to evaluate the resistance to rice neck blast for rice breeding. [ABSTRACT FROM AUTHOR]

Botryosphaeria dothidea is a significant plant pathogen responsible for causing ulcers, wilt, and fruit decay across a wide range of host plants. One notable fungal disease attributed to B. dothidea is pear tree ring rot, which currently ranks among the most severe diseases affecting pear trees in China. This pathogen primarily targets branches and fruits, occasionally impacting leaves as well, leading to tree weakening, fruit rot, and leaf drop. The annual repercussions of this disease severely affect both the yield and quality of pear fruits, thereby impeding the healthy development of the pear industry. Recent studies have indicated that other species within the B. dothidea complex can also induce pear ring rot; however, specific physiological strains of B. dothidea remain unreported. Consequently, this study collected tissues from pear trees infected with ring rot from orchards located in Liaoning, Hebei, Shandong, and other regions throughout China. Through morphological characterization combined with pathogenicity assessments and DNA sequence comparisons involving partial internal transcribed spacer (ITS), translation elongation factor (TEF), and β-tubulin (TUB) genes, 21 strains belonging to the Botryosphaeria spp. were identified. These 21 strains served as research subjects for inoculating dormant annual branches from 30 germplasm resources of pear trees in vitro. The results demonstrated that all tested strains could induce lesions on the branches which were characterized by dark brown spots. Furthermore, inoculation experiments involving these 21 strains were conducted to evaluate the resistance levels of various pear varieties against ring rot disease. The resistance was assessed by inoculating different isolates onto distinct pear varieties; this approach established the criteria for evaluating resistance while minimizing identification errors stemming from the variable responses exhibited by certain varieties towards individual strains. Ultimately, this study aims to provide a theoretical foundation for effective prevention and treatment strategies against pear ring rot. [ABSTRACT FROM AUTHOR]

Asian corn borer (ACB), Ostrinia furnacalis, is an important agricultural pest affecting maize production in southwestern China, but knowledge of the toxic effect of Bt maize on the pest has been insufficient until now. In this study, we determined the susceptibility of ACB to Cry1Ab, Vip3Aa, and their complex proteins and evaluated the efficacy of Chinese domestic Bt-(Cry1Ab+Vip3Aa) maize ("DBN3601T" event) against the pest in Yunnan Province of southwestern China. The susceptible bioassay indicated that the LC50 values of the Cry1Ab and Cry1Ab+Vip3Aa proteins expressed by the Bt maize varieties against ACB larvae were 51.42 and 46.85 ng/g, respectively; however, the ACB larva was insensitive to the Vip3Aa protein. The Cry1Ab+Vip3Aa protein contents in V6–V8 leaves, VT tassels, R1 silks, R2 kernels, R3 stalks and R3 cobs of the Bt-(Cry1Ab+Vip3Aa) maize were 114.20, 30.69, 3.77, 8.92, 11.09 and 10.99 μg/g, respectively. The larval feeding test indicated that the Bt-(Cry1Ab+Vip3Aa) maize was more toxic to the early instar larvae, and the survival time of larvae fed on the leaves was the shortest, while it survived the longest on stalks. The identification of maize resistance levels in the field showed that both larval density and plant damage score of Bt-(Cry1Ab+Vip3Aa) maize were significantly lower than those in conventional maize. It is concluded that the Bt-(Cry1Ab+Vip3Aa) maize can be used for control of the ACB in southwestern China. [ABSTRACT FROM AUTHOR]

Currently, the investigation on the collapse performances of steel frames with various structural scales has not formed a system resultant force, which leads to the current "overall qualitative and local quantitative" modes of structural system anticollapse resistance design. This paper numerically and analytically investigated the load-bearing capacities of the frame assemblies with various structural scales extracted from an overall steel frame structure subjected to the removal of an internal column. First, the accuracy of the numerical simulation methods was verified by comparing with the experimental results of the representative experimental collapse tests with various structural scales. Afterwards, numerical simulation analysis was conducted to investigate the variations in load-resisting capacities, axial forces generated in beams, and bending moments at beam ends in frame assemblies with different structural scales. The finding revealed that the boundary constraint is the one of the most critical parameters influencing the development of various load-bearing mechanisms, which is critical to identifying the internal links among the load-resisting capacities of assemblies with varying different scales. Finally, theoretical analysis methods for achieving the correlation transformation of the collapse capacities of steel frames with different structural scales were proposed, using member resistance based on the evolution laws of internal force among each story beam. The load-displacement curves generated by the display expression and its corresponding numerical models demonstrate a high level of accuracy, which demonstrates that the analytical methods can be employed for structural resistance evaluation before the anticollapse design. [ABSTRACT FROM AUTHOR]

Sorghum northern anthracnose is a leaf disease affecting sorghum, which results in plant death and substantial yield loss. This study aimed to effectively understand the disease, clarify its biological characteristics, and evaluate the resistance of germplasm resources. A field sample was collected to isolate and purify the pathogen. The pathogen, identified as Kabatiella zeae Narita et Hiratsuka using both morphological and molecular techniques, was further confirmed as the causative agent of northern anthracnose of sorghum following Robert Koch's principles. The results revealed the optimal culture temperature to be 25 °C, preferred dark culture conditions, and the best growth on potato glucose agar medium with sucrose and L-leucine as the optimal carbon and nitrogen sources, respectively. A total of 138 sorghum germplasm resources were inoculated and evaluated using the isolated pathogen, with 20 lines (14.49%) exhibiting high resistance, 18 lines (13.04%) showing disease resistance, 27 lines (19.57%) demonstrating medium resistance, 37 lines (26.81%) being susceptible, and 36 lines (26.09%) classified as highly susceptible. The indoor fungicide screening was conducted through pathogen medium application, and enilconazole, pyraclostrobin, methylthiophanate, and flusilazole were screened for the best fungicide inhibition with a 100% inhibition rate compared with the control. This study provides reference for field pharmaceutical control in sorghum production. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Kiwifruit canker and brown spot are significant diseases affecting kiwis, caused by Pseudomonas syringae pathogenic variations (Pseudomonas syringae pv. Actinidiae (Psa)) and Corynesporapolytica (Corynespora cassiicola). At present, the research on canker disease and brown spot disease mainly focuses on the isolation and identification of pathogenic bacteria, drug control, resistance gene mining and functional verification. Practice has proved that breeding disease resistant varieties are an effective method to control canker disease and brown spot disease. However, most existing cultivars lack genes for canker and brown spot resistance. Wild kiwifruit resources in nature exhibit extensive genetic diversity due to prolonged natural selection, containing numerous resistance genes. But, due to insufficient understanding of the resistance of most kiwifruit varieties (lines) to canker disease and brown spot disease, some high-quality resources have not been fully utilized. The incidence of canker and brown spot of 18 kiwifruit cultivars (lines) was measured by inoculating isolated branches and leaves, and their resistance to canker and brown spot was analyzed according to the length, disease index, mean diameter, and systematic clustering. The results were as follows: Among 18 different kiwifruit varieties (lines) for canker disease, there were two highly resistant materials, eight disease-resistant materials, four disease-susceptible materials, and two highly susceptible materials. Moreover, regarding brown spot disease, there were one highly resistant material, five disease- resistant materials, four susceptible materials, and three highly susceptible materials. Furthermore, four resources were resistant to both diseases. The outcomes provided a theoretical basis for breeding kiwifruit against canker and brown spot. [ABSTRACT FROM AUTHOR]

Abstract Background Stemphylium blight incited by Stemphylium botryosum poses a significant threat to lentil crops worldwide, inducing severe defoliation and causing substantial yield losses in susceptible varieties under favorable conditions. While some moderate levels of resistance have been identified within lentil germplasm, a low number of resistant cultivars are available to farmers. Adding to the common constraints of resistance breeding, a notable challenge is generating a sufficient number of spores for large-scale screenings, which are essential for pinpointing additional sources of resistance for integration into breeding programs. Therefore, there is a pressing need to improve existing screening methods and tailor them for large-scale material selection. In pursuit of this objective, a protocol for the efficient production of fungal material has been adapted. Results Optimization of fungal material production was successfully achieved by comparing the use of fungal mycelia and spores. Spore production was found to be optimal when produced on solid V8-PDA(hi) medium, while liquid Richard’s medium was identified as superior for mycelium yield. Furthermore, a refined screening method was developed by evaluating the resistance of six lentil accessions to stemphylium blight. This assessment included the use of either fungal mycelia (at densities ranging from 1 to 5 g L− 1) or spores (with densities ranging from 5 × 104 to 2 × 105 conidia mL− 1) under three different relative humidity levels (from 50 to 100%). Both humidity levels and inoculum dose significantly influenced the final disease rating (DR) and the relative Area Under the Disease Progress Curve (rAUDPC). Differences among genotypes in final symptom severity (DR) became more pronounced after inoculation with inoculum densities of 5 g L− 1 of mycelium or of 105 and 2 × 105 conidia mL− 1 of spore under 100% relative humidity. Given the challenges associated with the large-scale production of S. botryosum spores, inoculations with 5 g L− 1 of mycelium is highly recommended as a practical alternative for conducting mass-scale screenings. Conclusions The findings from this study underscore the critical importance of maintaining high level of humidity during inoculation and disease progression development for accurately assessing resistance to stemphylium blight. The optimization of mycelial production for suspension inoculation emerges as a more reliable and efficient approach for conducting large-scale screening to assess germplasm resistance against stemphylium blight in lentil crops.

Background: Stemphylium blight incited by Stemphylium botryosum poses a significant threat to lentil crops worldwide, inducing severe defoliation and causing substantial yield losses in susceptible varieties under favorable conditions. While some moderate levels of resistance have been identified within lentil germplasm, a low number of resistant cultivars are available to farmers. Adding to the common constraints of resistance breeding, a notable challenge is generating a sufficient number of spores for large-scale screenings, which are essential for pinpointing additional sources of resistance for integration into breeding programs. Therefore, there is a pressing need to improve existing screening methods and tailor them for large-scale material selection. In pursuit of this objective, a protocol for the efficient production of fungal material has been adapted. Results: Optimization of fungal material production was successfully achieved by comparing the use of fungal mycelia and spores. Spore production was found to be optimal when produced on solid V8-PDA(hi) medium, while liquid Richard's medium was identified as superior for mycelium yield. Furthermore, a refined screening method was developed by evaluating the resistance of six lentil accessions to stemphylium blight. This assessment included the use of either fungal mycelia (at densities ranging from 1 to 5 g L− 1) or spores (with densities ranging from 5 × 104 to 2 × 105 conidia mL− 1) under three different relative humidity levels (from 50 to 100%). Both humidity levels and inoculum dose significantly influenced the final disease rating (DR) and the relative Area Under the Disease Progress Curve (rAUDPC). Differences among genotypes in final symptom severity (DR) became more pronounced after inoculation with inoculum densities of 5 g L− 1 of mycelium or of 105 and 2 × 105 conidia mL− 1 of spore under 100% relative humidity. Given the challenges associated with the large-scale production of S. botryosum spores, inoculations with 5 g L− 1 of mycelium is highly recommended as a practical alternative for conducting mass-scale screenings. Conclusions: The findings from this study underscore the critical importance of maintaining high level of humidity during inoculation and disease progression development for accurately assessing resistance to stemphylium blight. The optimization of mycelial production for suspension inoculation emerges as a more reliable and efficient approach for conducting large-scale screening to assess germplasm resistance against stemphylium blight in lentil crops. [ABSTRACT FROM AUTHOR]

The breeding and selection of resistant varieties is an effective way to minimize wheat Fusarium head blight (FHB) hazards, so it is important to identify and evaluate resistant varieties. The traditional resistance phenotype identification is still largely dependent on time-consuming manual methods. In this paper, the method for evaluating FHB resistance in wheat ears was optimized based on the fusion feature wavelength images of the hyperspectral imaging system and the Faster R-CNN algorithm. The spectral data from 400-1000 nm were preprocessed by the multiple scattering correction (MSC) algorithm. Three feature wavelengths (553 nm, 682 nm and 714 nm) were selected by analyzing the X-loading weights (XLW) according to the absolute value of the peaks and troughs in different principal component (PC) load coefficient curves. Then, the different fusion methods of the three feature wavelengths were explored with different weight coefficients. Faster R-CNN was trained on the fusion and RGB datasets with VGG16, AlexNet, ZFNet, and ResNet-50 networks separately. Then, the other detection models SSD, YOLOv5, YOLOv7, CenterNet, and RetinaNet were used to compare with the Faster R-CNN model. As a result, the Faster R-CNN with VGG16 was best with the mAP (mean Average Precision) ranged from 97.7% to 98.8%. The model showed the best performance for the Fusion Image-1 dataset. Moreover, the Faster R-CNN model with VGG16 achieved an average detection accuracy of 99.00%, which was 23.89%, 1.21%, 0.75%, 0.62%, and 8.46% higher than SSD, YOLOv5, YOLOv7, CenterNet, and RetinaNet models. Therefore, it was demonstrated that the Faster R-CNN model based on the hyperspectral feature image fusion dataset proposed in this paper was feasible for rapid evaluation of wheat FHB resistance. This study provided an important detection method for ensuring wheat food security. [ABSTRACT FROM AUTHOR]

Botryosphaeria dothidea is a significant plant pathogen responsible for causing ulcers, wilt, and fruit decay across a wide range of host plants. One notable fungal disease attributed to B. dothidea is pear tree ring rot, which currently ranks among the most severe diseases affecting pear trees in China. This pathogen primarily targets branches and fruits, occasionally impacting leaves as well, leading to tree weakening, fruit rot, and leaf drop. The annual repercussions of this disease severely affect both the yield and quality of pear fruits, thereby impeding the healthy development of the pear industry. Recent studies have indicated that other species within the B. dothidea complex can also induce pear ring rot; however, specific physiological strains of B. dothidea remain unreported. Consequently, this study collected tissues from pear trees infected with ring rot from orchards located in Liaoning, Hebei, Shandong, and other regions throughout China. Through morphological characterization combined with pathogenicity assessments and DNA sequence comparisons involving partial internal transcribed spacer (ITS), translation elongation factor (TEF), and β-tubulin (TUB) genes, 21 strains belonging to the Botryosphaeria spp. were identified. These 21 strains served as research subjects for inoculating dormant annual branches from 30 germplasm resources of pear trees in vitro. The results demonstrated that all tested strains could induce lesions on the branches which were characterized by dark brown spots. Furthermore, inoculation experiments involving these 21 strains were conducted to evaluate the resistance levels of various pear varieties against ring rot disease. The resistance was assessed by inoculating different isolates onto distinct pear varieties; this approach established the criteria for evaluating resistance while minimizing identification errors stemming from the variable responses exhibited by certain varieties towards individual strains. Ultimately, this study aims to provide a theoretical foundation for effective prevention and treatment strategies against pear ring rot.

The percentage of Fusarium‐damaged kernels (FDK) was proposed as a type of Fusarium head blight (FHB) resistance displayed in matured wheat kernels. In this study, Qfdk.nau‐7D, a QTL identified in the Wangshuibai genome for its association with FDK, was introduced into FHB‐susceptible common wheat line PH691 through marker‐assisted selection and backcrossing. Evaluation of two resulted near‐isogenic lines (NILs) showed that the contribution of Qfdk.nau‐7D interval to lower FDK resulted from its effects on resistance to pathogen infection and to disease spread within the spike. Of a few major agronomic traits evaluated, head length was the only one that made difference between PH691 and the NILs. To reduce the QTL interval, a high‐density marker map was constructed using a BC3F2 population of 97 plants. Through resistance evaluation of the homozygous recombinant lines in repeated field trials, Qfdk.nau‐7D, designated as Fhb8, was placed in a 1.0‐cM Xwgrb1500‐Xwgrb1559 interval (from 93.9–96.5 Mb in CS) and showed co‐segregation with Xwgrb1587. Moreover, it was found that the association of Fhb8 with head length was due to close linkage with spike length QTL HL2. [ABSTRACT FROM AUTHOR]

Potato common scab (Streptomyces scabies) is a widespread disease and highly prevalent in recent years in the one cropping zone of northern China, the mixed cropping zone of southwestern China, and the two cropping zone of the Central Plains. The selection and breeding of potato common scab- resistant varieties is the most effective and economical method. The common scab resistance and the yield were evaluated for 31 potato varieties (lines) in 2022 by natural disease nursery method. In 2023, the 12 potato varieties (lines) identified in previous year were repeatedly evaluated. Among the 31 varieties (lines) tested in 2022, 11 potato varieties (lines), including 'Xisen 5', 'Z496', 'Z740', 'Z759', 'Z760', 'Z812', 'Z917', 'Z962', 'Z1148', 'Z1152' and 'Z1356', were resistant and their yields performed well. The repeated test results in 2023 showed that the 'Z962' was resistant to common scab (R) for two years, and there was no significant difference in yield compared with the local main variety 'Youjin'. The yields of 'Z1148', 'Z1152', 'Z1356', 'Z740', 'Z760' and 'Z917' were higher than those of the local main variety, but only the yield of 'Z740' was significantly different from the control, and was moderately resistant (MR) to common scab. 'Xisen 5' and 'Z496' were highly resistant to common scab and could be used as parent materials to create hybrid combinations for common scab resistance breeding. In this study, 31 potato materials were evaluated and screened for common scab resistance, which would provide basic materials for common scab resistance breeding, disease prevention and control. [ABSTRACT FROM AUTHOR]

Sorghum northern anthracnose is a leaf disease affecting sorghum, which results in plant death and substantial yield loss. This study aimed to effectively understand the disease, clarify its biological characteristics, and evaluate the resistance of germplasm resources. A field sample was collected to isolate and purify the pathogen. The pathogen, identified as Kabatiella zeae Narita et Hiratsuka using both morphological and molecular techniques, was further confirmed as the causative agent of northern anthracnose of sorghum following Robert Koch’s principles. The results revealed the optimal culture temperature to be 25 °C, preferred dark culture conditions, and the best growth on potato glucose agar medium with sucrose and L-leucine as the optimal carbon and nitrogen sources, respectively. A total of 138 sorghum germplasm resources were inoculated and evaluated using the isolated pathogen, with 20 lines (14.49%) exhibiting high resistance, 18 lines (13.04%) showing disease resistance, 27 lines (19.57%) demonstrating medium resistance, 37 lines (26.81%) being susceptible, and 36 lines (26.09%) classified as highly susceptible. The indoor fungicide screening was conducted through pathogen medium application, and enilconazole, pyraclostrobin, methylthiophanate, and flusilazole were screened for the best fungicide inhibition with a 100% inhibition rate compared with the control. This study provides reference for field pharmaceutical control in sorghum production.

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Copyright of Forest Research is the property of Forest Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

【Objective】The study was carried out to understand the Phytophthora disease resistance and genetic diversity of pepper germplasm materials, and to provide references for the establishment of core pepper germplasm bank and improvement of pepper Phytophthora disease resistance breeding.【Method】The Phytophthora disease resistance of 96 pepper germplasm materials was evaluated by using modified root irrigation inoculation method and the genetic diversity of them with 20 SSR molecular markers selected from the whole genome were analyzed.【Result】The results show that there was only 1 immune material, 6 highly resistant, 24 resistant, 53 susceptible and 12 highly susceptible materials among the 96 materials, which were basically consistent with the field performance. The results of genetic diversity analysis showed that a total of 79 alleles were detected among 20 SSR markers, with 2-9 alleles per marker and an average of 3.95 alleles. Shannon's index ranged from 0.2992 to 1.9893, with an average of 0.9513, indicating that the genetic polymorphism of the 20 SSR molecular markers selected was high. Nei's genetic diversity index ranged from 0.1614 to 0.8440, with an average of 0.5259, indicating high genetic diversity among materials. Cluster analysis results showed that the tested materials could be divided into three groups at the genetic distance of 0.37, including 3, 14 and 79 materials, respectively. Additionally, the genetic distance among 8 groups of materials was close to 0.【Conclusion】The improved root irrigation inoculation method is suitable for the identification of pepper Phytophthora disease, and the results are basically consistent with those of the field performance. Moreover, it is more convenient. The genetic polymorphisms of the 20 SSR molecular markers selected are high and suitable for genetic diversity analysis of pepper germplasms. The 96 pepper germplasm materials are rich in resources, but there are homogeneous materials, and some materials should be discarded properly during germplasm preservation.

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present study aimed to evaluate the resistance of 14 common tomato cultivars in the south of Kerman province and Hormozgan province, including Afra, Badro, Basimo, Bernetta, Brivio, Canyon, Comodoro, Elisa, Golsar, Karun, Matin, Sunseed 6189, 4129 and 8320 at the stage of four true-leaves against Fusarium oxysporum f. sp. radicis-lycopersici, under greenhouse conditions and to study the presence or absence of frl resistance gene in the tomato cultivars based on the SCARFrl marker. Based on the results of comparison of the disease index, morphological characteristics including root length, shoot height, root fresh and dry weight, shoot fresh weight and total fresh weight as well as frl gene amplification using SCARFrl-F/SCARFrlR primers, Canyon, Comodoro, Karun and 4129 were recognized as the most resistant and Bernetta, Elisa, Golsar and Matin were recognized as the most sensitive cultivars to FORL UJFCC1919. Other cultivars including Afra, Badro, Basimo, Brivio, Sunseed 6189 and 8320 showed different degrees of sensitivity to this pathogen. Using SCARFrl-F/SCARFrl-R primers, a 1000 bp fragment was amplified in the cultivars Canyon, Comodoro, Karun and 4129 which indicates the presence of frl gene with dominant homozygous (RR) alleles. Using this primer, a 950 bp fragment was amplified in Bernetta, Elisa, Golsar, Matin and 8320 cultivars, which indicates the absence of the frl gene and the presence of homozygous recessive (rr) alleles. In addition, in Afra, Badro, Basimo, Brivio and Sunseed 6189 cultivars, two 900-1000 bp fragments were amplified, which indicates the existence of heterozygous (Rr) alleles in these cultivars. [ABSTRACT FROM AUTHOR]

Introduction Every year, soli-borne pathogens of beans cause a lot of damage to this crop. Caudex and root rot of beans caused by Macrophomina phaseolina, Rhizoctonia solani, and Fusarium solani are among the most common diseases of this plant. Cultivating resistant species and maintaining shifting cultivation are among the most effective methods of controlling this disease Disease caused by Rhizoctonia solani include seedling death and in some cases cause rot of aerial parts. Macrophomina phaseolina is a plant-borne pathogen that has a wide range of hosts and causes extensive damage to farmers around the world each year. This fungus is a polyphage and causes disease in more than 500 different plant species such as soybeans, peas, pines, kiwis, cotton and sesame, peanuts, cotton, sunflower, melon. Fusarium solani f.sp. phaseoli Burk, is a fungus isolated from peas and red beans, it is present in most soils and causes disease on legumes and plants that grow in hot and humid conditions.Materials and Methods A factorial experiment in the form of Completely Randomized Design is conducted in order to evaluate the resistance level of beans species to these fungi. The factors consisted of species (five levels, containing Sadri, Shazand, Saleh, Dorsa, and Goli species) and fungi species (8 levels: each of three fungi alone, combined with each other, and a control sample without any fungus). The reaction of beans species was by calculating the severity of disease and evaluating dry and fresh weight of aerial organs and root and height of the bushes. Steps to perform the test: 1- Preparation of seedbed for planting and sowing seeds of bean cultivars 2- Planting seeds and start growing seedlings 3- Inoculation of seedlings 4- Determining the severity of the disease 5- Measuring the height of aerial parts of seedlingResults and Discussion Plants are equipped with several defense mechanisms to resist the attack of various pathogens. These include pre-existing structural or biochemical defenses that prevent pathogens from invading, or a series of induced structural and biochemical defenses after an attack. In natural ecosystems, most of the existing pathogenic models are the result of long-term evolution of both the host and the pathogen, and there is usually a high genetic diversity between plants and microbial populations. Today, with the widespread cultivation of cultivars with a uniform genetic background, it has led to the increasing development of susceptible strains of pathogens and the occurrence of widespread epidemics of plant diseases. Therefore, there is a great need to produce lasting resistance to pathogens in plants. Rhizoctonia solani, Macrophomina phasolina and Fusarium solani are fungi with widespread global damage to crops. Therefore, strategies to reduce the quantitative and qualitative damage of these fungi should be studied. In this study, it was observed that beans infected with Macrophomina phasolina, the first symptoms after about four weeks, were yellowing of leaves, wilting of the plant and discoloration of root vascular tissue to reddish-black brown. Also, plants infected with Fusarium solani and Rhizoctonia solani turned the root skin brown. With the spread of disease-causing fungi, necrosis of the crown and roots of tissues was observed. In this case, the color of the vessels changed and turned yellow to brown. Restriction of root development, slow growth of plant shoots, symptoms of leaf yellowing and paleness similar to the symptoms of nutrient deficiency and wilting and leaf fall were the obvious symptoms of these diseases. The results of this study showed that Sadri and Darsa cultivars had relative resistance to all three fungi alone, but Sadri cultivar also showed relative resistance to binary combinations of fungi. But none of the cultivars used were resistant to all three fungi. The experimented species reacted differently to the pathogenic fungi. The maximum and minimum severity of the disease was observed in Goli and Sadri species respectively. The maximum height of seedling was observed in Sadri and Shazand species infected with R. solani and M. phaseolina pathogenic fungi and the combination of these two fungi with Shazand. The maximum dry and fresh weight of aerial organs and roots of infected seedlings was observed in Sadri species infected with F. solani fungus.Conclusion The research results indicated that Sadri species, with minimum severity of disease and maximum height and fresh and dry weight of aerial organs and root, was the most resistant species to all three fungi solely and combined.

To identify excellent cultivars resistant to Fusarium head blight (FHB), 104 wheat cultivars were tested by single‐flower inoculation using two prevalent pathogens from 2018 to 2020. Agronomic traits were also investigated. Six FHB‐resistance quantitative trait loci (QTL), Fhb1, Fhb2, Fhb4, Fhb5, Fhb7 and Qfhb.crc‐2D, have been assessed using previously reported DNA markers. A diagnostic marker has been used for Fhb1, and indicative markers linked to the other QTL were used. Results showed that (i) 12 (11.5%) cultivars were resistant to two pathogens in 3 years; among them, 'Shengxuan 6', 'Wanhongbian 759', 'Yunong 903' and 'Yunong 901' had good agronomic traits. (ii) Among cultivars with one resistance QTL, the severities of cultivars carrying Fhb1 and Qfhb.crc‐2D were 2.2 and 2.8, respectively, whereas those of cultivars with Fhb2 or Fhb7 were 3.6. Among cultivars with two resistance QTL, the severities of cultivars with Fhb1 + Fhb4, Fhb1 + Fhb7 and Fhb4 + Fhb5 were 2.2, 3.0 and 3.6, respectively. The severity of five cultivars possessing three or four resistance QTL was below 2.5. Fhb1 and Qfhb.crc‐2D showed better resistance effects than other resistance QTL. [ABSTRACT FROM AUTHOR]

Viral and other diseases are important limiting factors of the potato industry in China. For management of these diseases in potatoes, the resistances against potato virus Y (PVY), potato virus X (PVX), potato virus S (PVS), and potato virus A (PVA) were evaluated in 15 late-maturing potato varieties (lines) from Northern China by mechanical inoculation in this study, and the diseases related molecular markers were also detected. Ten potato varieties (lines) exhibited resistance to at least one of the tested viruses, among which 'Jingzhangshu 4', 'Jizhangshu 8', 'Jizhangshu 12', '2013-19-14', and '2013-89-2' were resistant to three of four tested viruses, indicating that these potatoes expressed good comprehensive resistance to viruses. The marker detection results revealed that the PVY resistance in 'Jizhangshu 8', '2013-38-32', and '2013-89-2' were possibly derived from Ryadg, Rychc, and Rysto, respectively, while the PVX resistance in 'Jizhangshu 12' was probably derived from Rx1. According to the degree of coincidence between markers and phenotypes, the PVY and PVX resistance in these potato varieties (lines) may be mainly from Rysto, and Rx1, respectively. Molecular markers also detected potato root-knot nematode resistance gene H1 in six potato varieties (lines) and potato late blight resistance gene R8 in four potato varieties (lines). This study may lay a foundation for the further utilization of these resistance resources and the pyramid breeding of multiple resistance genes. [ABSTRACT FROM AUTHOR]

Background: Tartary buckwheat (Fagopyrum tartaricum) is particularly vulnerable to pre-harvest sprouting (PHS) due to its extended flowering and fruiting cycle, especially during periods of prolonged rainfall. This susceptibility has significant adverse effects on yield, quality and post-harvest processing. In this study, a recombinant inbred lines (RILs) population (XJ-RILs) was developed from a cross between the PHS-susceptible Tartary buckwheat variety 'Xiaomiqiao' (female parent) and the highly PHS-resistant variety 'Jinqiaomai 2' (male parent). Key traits, including germination percentage, germination energy, germination index, field PHS (PHS-F) and simulated PHS (PHS-S), were evaluated, and a quantitative trait locus (QTL) mapping analysis was performed., Results: (i) PHS-S was strongly and significantly correlated with PHS-F. (ii) A total of 11 QTLs associated with seed germination and 14 QTLs related to PHS were identified. Notably, the major QTL cluster qPHS8-1 was consistently detected and mapped within the interval of 8.53-9.65 Mbp on chromosome Ft8. (iii) Genotyping of 221 XJ-RILs across eight chromosomes revealed five residual heterozygous lines carrying a heterozygous interval of qPHS8-1 cluster, with inbred line R56 being particularly suited for the fine mapping of qPHS8-1., Conclusion: The PHS-S test, conducted on entire Tartary buckwheat spikes, is an effective and comprehensive method for assessing PHS resistance in this crop. QTL mapping identified qPHS8-1 as a major locus for PHS resistance, and inbred line R56 offers a promising resource for further fine mapping of this cluster. © 2025 Society of Chemical Industry., (© 2025 Society of Chemical Industry.)

【Objective】To assess the degree of Phytophthora resistance of pepper germplasm resources and examine the indoor antifungal activity of common chemical agents against Phytophthora capsici, in order to provide guidance for the prevention and control of Phytophthora.【Methods】The resistance of 28 pepper germplasm resources to Phytophthora capsici was evaluated by root inoculation. The sensitivity of Phytophthora capsici S90 to 16 common fungicides in the market was analyzed by mycelial growth rate method.【Results】The disease resistance of different pepper germplasm resources was significantly different, and the disease index was 0-100. Among them, the disease index of C164, C186, C167, C189, Beixing No.1 and Beixing No. 6 was 0, showing high resistance, accounting for 21.43% of the total resources. There were 1 medium resistant and 21 highly susceptible materials, accounting for 3.57% and 75.00% of the total resources, respectively. Among the 16 fungicides, the suspension of 32% pyraclostrobin·fluopicolide had the highest inhibitory activity of P. capsici S90, with EC50 value at 6.935 0 mg/L. The EC50 values of iprodione, carbendazim, myclobutanil, ethylicin and pyraclostrobin were 21.504 7 to 93.587 8 mg/L. The EC50 values of other fungicides were all greater than 100 mg/L, among which, fluopyramotri·floxystrobin and chlorobromoisocy anuric acid had no inhibitory effect on P. capsici S90.【Conclusion】In the tested pepper germplasm resources, there were six varieties with high Phytophthora capsici resistance. Among the 16 fungicides tested, the suspension of 32% pyraclostrobin·fluopicolide had the highest inhibitory effect on P. capsici S90. Iprodione, carbendazim, myclobutanil, ethylicin and pyraclostrobin also had some inhibitory activities that could be used as effective fungicides for controlling Phytophthora. [ABSTRACT FROM AUTHOR]

Abstract Background Mulberry (Morus alba L.) is an important sericulture crop; however, root-knot nematode infection seriously limits its production. Understanding the mechanism of interaction between mulberry and nematode is important for control of infection. Results Using sequencing and de novo transcriptome assembly, we identified 55,894 unigenes from root samples of resistant and susceptible mulberry cultivars at different stages after infection with the nematode Meloidogyne enterolobii; 33,987 of these were annotated in the Nr, SWISS-PROT, KEGG, and KOG databases. Gene ontology and pathway enrichment analyses of differentially expressed genes (DEGs) revealed key genes involved in hormone metabolic processes, plant hormone signal transduction, flavonoid biosynthesis, phenylpropanoid biosynthesis, and peroxisomal and photosynthetic pathways. Analysis of key trends in co-expression networks indicated that expression of unigenes 0,015,083, 0,073,272, 0,004,006, and 0,000,628 was positively correlated with resistance to M. enterolobii. Unigene 0015083 encodes tabersonine 16-O-methyltransferase (16OMT), which is involved in alkaloid biosynthesis. Unigene 0073272 encodes a transcription factor contributing to nitric oxide accumulation during plant immune responses. Unigenes 0,004,006 and 0,000,628 encode ERF and MYB transcription factors, respectively, involved in plant hormone signaling. We verified the accuracy of transcriptome sequencing results by RT-qPCR of 21 DEGs. Conclusions The results of this study increase our understanding of the resistance mechanisms and candidate genes involved in mulberry–M. enterolobii interaction. Thus, our data will contribute to the development of effective control measures against this pathogen.

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Copyright of Acta Agronomica Sinica is the property of Crop Science Society of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Background The black pod disease affects cacao plantations worldwide; it is caused by the oomycete species of the genus Phytophthora. The resistance of cacao plants to the black pod is commonly evaluated by artificial inoculation of the pathogen and the monitoring of the disease symptoms. However, it is difficult to identify resistant plants because the commonly used methods for the inoculation of the pathogens produce inconsistent results. Therefore, this study aimed to develop an efficient and reliable method to evaluate the resistance of Theobroma cacao seedlings to the infection by Phytophthora palmivora. Results Seedlings of different cacao genotypes were inoculated with P. palmivora under greenhouse conditions using the previously reported inoculation methods and a newly proposed method, the agar–water solution method. While none of the previously reported methods was effective, the agar–water solution method ensured a 100% seedling infection under greenhouse conditions. The proposed agar–water methodology is fast, simple and reproducible. Furthermore, the evaluation of this method in susceptible (CCN-51) and tolerant (SCA-6) T. cacao genotypes produced the expected contrasting results. Conclusions The agar–water solution method presented in this study is an efficient alternative inoculation protocol for the identification of cacao genotypes that are resistant to black pod under greenhouse conditions.

Wheat stripe rust (yellow rust), caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most serious diseases in wheat. To address the threat of predominant Pst races to wheat production and screen resistance resources to breed new wheat cultivars in China, the resistance of 93 wheat landraces derived from Qinghai-Tibet spring and winter wheat zones to stripe rust were evaluated at seedling stage and adult plant stage, and the Yr genes that they might carry were detected. The resistance of 93 wheat landraces were evaluated at seedling stage in a greenhouse with two Pst races CYR32 and CYR34, and at adult plant stage under four field conditions with the mixture of Pst races (CYR32, CYR33, CYR34, Su11-4, Su11-5, and G22-14) in Chongzhou and Mianyang, Sichuan during 2015-2016, 2017-2018, and 2018-2019 cropping seasons, respectively. The panel of wheat land- races was detected with flanking markers closely linked to stripe rust resistance genes Yr5, Yr10, Yr18, Yr24 (=Yr26), Yr48, Yr65, and Yr67. Resistance evaluation indicated that four landraces (4.30%) were resistant to CYR32, three (3.26%) resistant to CYR34, and one was resistant to both CYR32 and CYR34 at seedling stage. Ten landraces displayed resistance to mixed races at adult plant stage under four field conditions. Molecular detection indicated that 11, 40, and 1 landrace might carry Yr18, Yr48, and Yr65, respectively. Seven landraces may carry both Yr18 and Yr48. In addition, no Yr genes were detected in the three resistant wheat landraces, indicating that these wheat landraces might carry other known or unknown stripe rust resistance genes. The wheat landraces derived from Qinghai-Tibet spring and winter wheat zones showed low levels of resistance to the current predominant Pst races in China, and they carried less resistance genes. These wheat landraces with good resistance and carrying known or unknown resistance genes should be valued to explore novel stripe rust resistance genes and accelerate their utilization in wheat breeding program. [ABSTRACT FROM AUTHOR]

Anthracnose caused by Colletotrichum lindemuthianum is one of the most important bean diseases in Iran. In this study, the presence of disease resistance genes was investigated using 10 pairs of SCAR primers in 12 Iranian bean cultivars. Also, disease symptoms were evaluated based on the intensity index in the greenhouse condition. Amplification of SCAR markers SAS13, SY20, SZ04 and SB12 indicated the presence of Co-4 2, Co-4, Co-6 and Co-9 resistant genes respectively. Cultivars Akhtar, Derakhshan, Almas, Talash and Koosha contained Co-4 ², Co-4 and Co-6 resistance gene revealed by amplification of SBB14, SC08 and SZ20 markers accordingly. Co-4 ² gene was detected in Goli and Naz cultivars and Co-4 and Co-4 ² genes were present in Pak, Sadri and Khomein cultivars. Co-4 ² gene that is linked to SH18 marker was observed in Dorsa and Shokofa cultivars. The presence of Co-2 resistance gene was observed only in Almas cultivar. Co5 gene linked to SAB3 marker was only observed in the related differential cultivars. Phenotypic evaluation for disease symptoms showed that out of 12 cultivars studied, four (Naz, Almas, Dorsa and Shokofa) showed resistance reaction and two (Akhtar and Goli) were moderately resistant. Based on the intensity of the disease index, these cultivars were considered relatively resistance. Simultaneous analysis of molecular and phenotypic data showed that only the two markers of SQ4 and SH18 yielded in amplifying the expected band in the resistant cultivars Diamond, Shokofa and Dorsa. The results of this study will be beneficial for producing resistant bean cultivars against anthracnose disease by pyramiding of the resistance genes. [ABSTRACT FROM AUTHOR]

Copyright of Acta Prataculturae Sinica is the property of Acta Prataculturae Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fusarium head blight (FHB) mainly caused by Fusarium species is one of the most important diseases threatening worldwide wheat production. To develop new FHB resistance resources, disease resistances of three new wheat lines L958, L962 and L987 were evaluated over a period of several years. We employed L699 (PI672540) and L661 as the resistant and susceptible control, respectively. Moderate FHB resistance was observed in these three wheat lines, among which the genotype L958 was found a good resource for yield, quality and FHB resistance improvement. In addition, genotype L962 was found to be resistant to powdery mildew, and both L958 and L987 carried the YrL693 gene conferring stripe rust resistance. The study provides promising results for accelerating the resistance breeding of the three wheat lines.

Addition chain is a well-known approach for implementing higher-order masked SBoxes. However, this approach induces more computations of intermediate monomials over F2n, which in turn leak more information related to the sensitive variables and may decrease its side-channel resistance consequently. In this paper, we introduce a new notion named polygon degree to measure the resistance of monomial computations. With the help of this notion, we select several typical addition chain implementations with the strongest or the weakest resistance. In practical experiments based on an ARM Cortex-M4 architecture, we collect power and electromagnetic traces in consideration of different noise levels. The results show that the resistance of the weakest masked SBox implementation is close to that of an unprotected implementation, while the strongest one can also be broken with fewer than 1,500 traces due to extra leakages. Moreover, we study the resistance of addition chain implementations against profiled attacks. We find that some monomials with smaller output size leak more information than the SBox output. The work by Duc et al. at JOC 2019 showed that for a balanced function, the smaller the output size is, the less information is leaked. Thus, our attacks demonstrate that this property of balanced functions does not apply to unbalanced functions.

[Objective] Black spot disease was an important disease in the process of rose field planting. The pathogen was Marsonina rosae and breeding rose varieties with resistance to black spot was one of the main ways to resist black spot. [Method] In order to screen out the rose germplasm resources with high resistance to black spot, 46 wild rose species from 9 groups of Rosa were evaluated for resistance to black spot in laboratory and field. The activities of superoxide dismutase (SOD), peroxidase (POD) and polyphenol oxidase ( PPO) were measured in the selected immune and highly sensitive materials, and the leaf tissue structure was observed by scanning electron microscope. [Result] The results showed that the indoor identification results were basically consistent with the field identification results. Among 46 Rosa germplasm resources, 2 immune materials and 13 high resistance materials were identified. After infected with black spot disease, the activity of 3 enzymes of resistant varieties was higher than that of susceptible varieties. The PPO activity of susceptible Wild R. odorata var. erubescens reached 767. 78%. Scanning electron microscopy showed that the epidermal cells of the cotyledons of Rosa l.aevigata were closely arranged, the wax layer was dense and uniform, the stomatal opening and closing degree was small, and the leaf structure was not easy to be infected with black spot pathogen; the high sensitive material of Rosa odoraia var. erubescens rose leaves were loose, the waxy layer was not evenly distributed, the stomatal opening degree was large, and the leaf structure was more susceptible to black spot pathogens. [Conclusion] Leaf enzyme activity, leaf cuticular wax layer and stomatal opening and closing degree can be used as preliminary identification indexes for resistance screening of black spot. The wild germplasm resources screened in the present experiment could be used as parents for disease resistance breeding, and new rose varieties with high resistance to black spot could be selected by means of cross breeding or molecular breeding. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Oil Crop Sciences is the property of Oil Crops Research Institute of Chinese Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Mulberry (Morus alba L.) is an important sericulture crop; however, root-knot nematode infection seriously limits its production. Understanding the mechanism of interaction between mulberry and nematode is important for control of infection. Results: Using sequencing and de novo transcriptome assembly, we identified 55,894 unigenes from root samples of resistant and susceptible mulberry cultivars at different stages after infection with the nematode Meloidogyne enterolobii; 33,987 of these were annotated in the Nr, SWISS-PROT, KEGG, and KOG databases. Gene ontology and pathway enrichment analyses of differentially expressed genes (DEGs) revealed key genes involved in hormone metabolic processes, plant hormone signal transduction, flavonoid biosynthesis, phenylpropanoid biosynthesis, and peroxisomal and photosynthetic pathways. Analysis of key trends in co-expression networks indicated that expression of unigenes 0,015,083, 0,073,272, 0,004,006, and 0,000,628 was positively correlated with resistance to M. enterolobii. Unigene 0015083 encodes tabersonine 16-O-methyltransferase (16OMT), which is involved in alkaloid biosynthesis. Unigene 0073272 encodes a transcription factor contributing to nitric oxide accumulation during plant immune responses. Unigenes 0,004,006 and 0,000,628 encode ERF and MYB transcription factors, respectively, involved in plant hormone signaling. We verified the accuracy of transcriptome sequencing results by RT-qPCR of 21 DEGs. Conclusions: The results of this study increase our understanding of the resistance mechanisms and candidate genes involved in mulberry–M. enterolobii interaction. Thus, our data will contribute to the development of effective control measures against this pathogen. [ABSTRACT FROM AUTHOR]

Walnut anthracnose is one of the most serious diseases of walnut globally. In this study, the pathogen was identified as Colletotrichum gloeosporioides by morphological and molecular approaches. Then, the resistance of 18 walnut genotypes was evaluated by field investigation as well as field and detached leaflet inoculation. A field inoculation assay was used as a benchmark for comparing field evaluation and the detached leaflet inoculation assay. Seven genotypes, Panhe1 and clones 71 and 200 of Juglans sigillata, Yanyuanzao and Qingxiang of J. regia, and Shujiang1 and Chuanzao1 of J. regia × J. sigillata, displayed high resistance in all assays, suggesting that they may be good candidates for further evaluation. Subsequently, two genotypes (Panhe1 with high resistance, and clone 199 with high susceptibility) were selected to analyse the different physiological responses between highly resistant and susceptible genotypes after inoculation. C. gloeosporioides infection induced the activities of superoxide dismutase (SOD), peroxidase (POD), polyphenol oxidase (PPO), and chitinase; they were all significantly increased in both Panhe1 and clone 199. However, the POD activity and its change rate in Panhe1 were significantly higher than those in clone 199. The change rates of PPO activity, and total phenol and proline content in Panhe1 were significantly higher than those in clone 199. Moreover, the change rates of SOD activity, malondialdehyde, and soluble sugar content in clone 199 were significantly higher than those in Panhe1. These findings not only enhance our understanding of the resistance of walnut to anthracnose, but also lay the foundation for breeding anthracnose‐resistant walnuts in the future. [ABSTRACT FROM AUTHOR]

In this study, four genotypes (Acva-1, Acva-2, Acva-3 and ZM-2) of Actinidia germplasm resources were grown in different NaCI concentrations (0, 0.4, 0.8 and 1.2 g L–1). The growth, physiological and biochemical indicators were measured, and a graded scale was developed as the salt damage index (SDI) according to different damage symptoms in leaves. The results showed SDI increased gradually, and average number and length of new shoot decreased significantly. Three antioxidant enzymes (superoxide dismutase, peroxidase and catalase) and two osmotic adjustment substances (soluble sugar and proline) showed different changes in old and new leaves of four genotypes. SPAD values exhibited a decreased trend in the whole except in the new leaves of Acva-2. Malonaldehyde contents increased and root activity decreased with the increasing salt concentrations. Principal component analysis was used to assess the salt tolerance, and the results showed Acva-3, from Actinidia valvata Dunn., had the strongest tolerance to salt, and could be a potential resistant resource to the salt-tolerance dedicated rootstock breeding of kiwifruit.

Sorghum is an important source of food, feed and raw material for brewing, and is expected to be a promising bioenergy crop. Sorghum is well known for its strong resistance to abiotic stress and wide adaptability, and salt tolerance is one of its main characteristics. Increasing sorghum planting acreage on saline-alkalien land is one way to effectively use this kind of marginal soil. In this paper, domestic and overseas research on plant tolerance to soil salinity and alkalinity in sorghum, including salt-tolerant genetics and breeding, physiology, cultivation, and identification of tolerant germplasms, are reviewed. Suggestions for further studies on salinity and alkalinity tolerance in sorghum are given, and the prospects for sorghum production in saline-alkalien land are discussed.

The root-knot nematode Meloidogyne graminicola, which is distributed worldwide, is considered a major constraint on rice production in Asia. The present study used the root gall index and number of nematodes inside the roots to evaluate resistance/susceptibility to M. graminicola in different subpopulations of Oryza sativa (aus, hybrid aus, indica, hybrid indica, temperate japonica, tropical japonica). Nematode development in highly resistant varieties was also evaluated. Analyses of randomly selected 35 varieties showed the number of M. graminicola nematodes inside the roots correlated very strongly (r=0.87, P≤0.05) with the nematode gall index, and the results from pot and field experiments revealed similar rankings of the varieties for resistance/susceptibility. Among the 136 tested varieties, temperate japonica displayed the highest gall index, followed by tropical japonica, indica, hybrid indica, aus, and hybrid aus. Zhonghua 11 (aus), Shenliangyou 1 (hybrid aus) and Cliangyou 4418 (hybrid indica) were highly resistant to M. graminicola under both pot and field conditions. Further examination of nematode development suggested that compared to susceptible rice, M. graminicola penetrated less often into highly resistant varieties and more frequently failed to develop into females. The promising varieties found in the present research might be useful for the breeding of hybrid rice in China and for the further development of practical nematode management measures.

Copyright of Journal of South China Agricultural University is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

【Objective】To evaluate the resistance to ring rot for apple and pear fruits in Hohhot of Inner Mongolia, and provide information for the breeding of disease resistance apple and pear cultivars in cold and drought area.【Methods】Taking Qiuxiang and Fuji as control, after inoculating the fruit of apple and pear with Physalospora piricola, the disease susceptibility rate, lesion diameter and lesion expansion rate were measured to evaluate the resistance of 7 kinds of apple and pear fruits(Jinhong, Shennong No.2, Lvhongbao, Jixinguo, Huoyanhaitang, Pingguo pear, Zaosu pear)in Hohhot to the disease. The micro structure of the resistant and the susceptible cultivar were compared by election microscopy.【Results】Pingguo pear, Huoyanhaitang were super susceptible cultivars to ring rot, Lvhongbao, Jinhong, Jixinguo and Zaosu pear were medium susceptible cultivars, Fuji and Qiuxiang were medium resistant cultivars, and Shennong No.2 was super resistant cultivar. The results of microstructural observation showed that Huoyanhaitang was susceptible cultivar and Shennong No.2 was resistant cultivar.【Conclusion】The Huoyanhaitang and Pingguo pear were super susceptible cultivars to ring rot, while Shennong No.2 was super resistant cultivar in Hohhot. [ABSTRACT FROM AUTHOR]

Bacterial canker of kiwifruit caused by Pseudomonas syringae pv. actinidiae (Psa) is a catastrophic disease that threatens the global kiwifruit industry. As yet, no cure has been developed. Planting resistant cultivars is considered as one of the most effective ways to control Psa. However, most existing cultivars lack Psa‐resistance genes. Wild Actinidia resources contain rich genetic diversity and may have powerful disease‐resistance genes under long‐term natural selection, but lack of knowledge about the resistance to Psa for most Actinidia species results in some excellent wild resistant genotypes being underutilized. In this study, the response to Psa of 104 wild genotypes of 30 Actinidia species (including 37 taxa) was tested with an in vitro bioassay, and a considerable number of individuals from different species with tolerance or high resistance to Psa were identified. The results showed high consistency between years. This is the first large‐scale evaluation of diverse Actinidia species with resistance to Psa through an in vitro bioassay. The resistant genotypes of A. chinensis identified could be used in future kiwifruit improvement programmes. The findings should help provide an understanding of the resistance to Psa. [ABSTRACT FROM AUTHOR]

[Objective] The resistance to Tetranychus cinnabarinus (Boisduval) of 84 cassava germplasms resources from the nursery of Guangxi Institute of Southern Tropical Agricultural Sciences was evaluated. [Method] Three random leaves were taken from cassava plants separately from the upper, middle and lower parts, 9 leaves from each plant to investigate the damage degree and calculate the mite damage index. [Result] The results showed that among the 84 cassava germplasms, 6 were resistant (R), 39 moderately resistant (MR), 31 sensitive (S), and 8 highly sensitive (HS). Six germplasms such as Guiken 09-11 and SC5 could be used as breeding materials with resistance, and the varieties with large planting area in Guangxi such as GR3, SC201, GR911, SC205 and SC11 were all moderately resistant. The resistance of edible cassava varieties was poor, among which GR891 and South Asia Cassava No. 1 have the lowest resistance. [Conclusion] No correlation was found between mite damage index of cassava germplasm and plant type, number of branches, lobe shape, leaf length, leaf width and leaf thickness. [ABSTRACT FROM AUTHOR]

Anthracnose caused by Colletotrichum truncatum is a major fungal disease of soybean, especially vegetable soybean (edamame). Studies of this disease have mainly focused on resistance evaluation, but the primary methods used—in vivo inoculation of pods or plants under greenhouse or field conditions—have limitations with respect to accuracy, stability, scale, and environmental safety. In this study, we developed a method for inoculating pods in vitro by soaking in a mycelial suspension. We optimized the crucial components, including the mycelial suspension concentration (40 to 60 mg mL−1), the maturity of the sampled pods (15 days after flowering), and the post-inoculation incubation period (5 days). Application of the mycelial suspension by soaking rather than spraying improved the efficiency of inoculation and made large-scale evaluation possible. Using this method, we evaluated 589 soybean germplasm resources (275 cultivars, 233 landraces, and 81 wild accessions). We identified 25 highly resistant cultivars, 11 highly resistant landraces, but only one highly resistant wild accession. Our results will aid future research on soybean anthracnose resistance, including gene discovery, the elucidation of molecular mechanisms, and the breeding of resistant cultivars.

The first reported case of Phoma macdonaldii Boerema that caused sunflower black stem disease in China was from Xinjiang Uygur Autonomous Region in 2008. Black spindle lesions were observed on sunflower stems in the fields of Inner Mongolia region in China. The causal agents were isolated from the infected stems. Cultures on potato dextrose agar (PDA) plates were whitish with black particles underneath. Dark and pear-like pycnidia with yellowish or dirty whitish exudates were also observed on the surface of the cultures. The cultures produce primarily non-septate conidia. The cultures could infect sunflowers stems by artificial inoculation and developed symptoms consistent with those in the field. Morphological characteristics and molecular identification indicated the isolated causal agents were P. macdonaldii. Phylogenetic analysis based on ITS1, 5.8 s RNA and ITS2 region confirmed the identification. Disease resistance assessments were performed on twenty sunflower varieties and the results suggested that the resistance of seven sunflower varieties to P. macdonaldii was above the average; SC89 and Longkuiza1 were susceptible to P. macdonaldii. [ABSTRACT FROM AUTHOR]