The severity and yield effects of the chocolate spot disease in faba bean affected by intercropping and nitrogen input.

BACKGROUND: The aim is to study the disease suppression efficiency, yield loss rate, and yield benefits of intercropped faba bean against chocolate spot under nitrogen (N) input, to clarify the effectiveness of intercropping faba beans in controlling chocolate spot and its contribution to yield increase. RESULTS: Four N input levels and disease suppression treatments were discovered when faba bean-wheat intercropped was used. Adding N enhanced the chocolate spot's area under disease progression curve (AUDPC) by 27.1-69.9%. In contrast to monoculture, intercropping reduced the AUDPC of the chocolate spot by 32.4-51.0% (P < 0.05). Interestingly, the relative control efficacy (RCE) of intercropping at the EShan site was better. With disease suppression or non-suppression, N input increased grain yield loss and its components in faba bean. The total yield advantage effect (TE) and disease-suppression effect (DSE) of faba bean intercropped at the two experimental sites were significantly increased under N input (N1 and N2 level). The proportion of recovery yield due to intercropping suppressed disease (DSE/TE ratio) in EShan (52.1%) was higher than that in Xundian (40.9%), and the DSE of intercropping played an indispensable role in the two sites. Regression analysis of AUDPC and grain yield loss amount showed that one unit increase in chocolate spot AUDPC could cause a grain yield loss of 0.38-0.86 kg ha-1 . The partial land equivalent ratio (pLER) of intercropping faba beans at the EShan site was > 0.33. CONCLUSION: In conclusion, intercropped faba bean with N treatment (45-90 kg ha-1 ) was the best choice for maximizing the intercropping disease control effect. © 2023 Society of Chemical Industry.

The complete chloroplast genome of Rubus pinfaensis, an edible and medicinal dual-purpose plant.

Rubus pinfaensis H. Lév. & Vaniot is of great importance in the phylogeny and evolution amongst Rosaceae, genus Rubus L. plants. The chloroplast genome of R. pinfaensis was reported in this study, which is 155,523 bp in size, with an average GC content of 37.13%. The complete chloroplast genome has a typical quadripartite structure, including a large single copy (LSC) region (85,211 bp) and a small single copy (SSC) region (18,718 bp), which were separated a pair of inverted repeats (IRs, 25,797 bp). This plastome contained 129 different genes (112 unique), including 85 protein-coding genes (79 unique), 36 tRNA genes (29 unique), and 8 rRNA genes (4 unique). The chloroplast genome of R. pinfaensis has completed that will be based on the phylogeny and genomic studies in the family Rosaceae, genus Rubus L.

Increased nodular P level induced by intercropping stimulated nodulation in soybean under phosphorus deficiency.

Low P availability is a vital constraint for nodulation and efficient N2 fixation of legume, including soybean. To elucidate the mechanisms involved in nodule adaption to low P availability under legume/cereal intercropping systems, two experiments consisting of three cropping patterns (monocropped soybean, monocropped maize, soybean/maize intercropping) were studied under both sufficient- and deficient-P levels. Our results demonstrated that intercropped soybean with maize showed a higher nodulation and N2 fixation efficiency under low P availability than monocropped soybean as evidenced by improvement in the number, dry weight and nitrogenase activity of nodules. These differences might be attributed to increase in P level in intercropping-induced nodules under low P supply, which was caused by the elevated activities of phytase and acid phosphatases in intercropping-induced nodules. Additionally, the enhanced expression of phytase gene in nodules supplied with deficient P level coincided with an increase in phytase and acid phosphatase activities. Our results revealed a mechanism for how intercropped maize stimulated nodulation and N2 fixation of soybean under P deficient environments, where enhanced synthesis of phytase and acid phosphatases in intercropping-induced nodules, and stimulated nodulation and N2 fixation.

The complete chloroplast genome of Rubus setchuenensis, an edible and medicinal dual-purpose wild plant.

Rubus setchuenensis Bureau et Franch. is important in phylogeny and evolution amongst genus Rubus L. (Rosaceae) plants. The chloroplast genome of R. setchuenensis reported in this study is 156,231 bp in size, with an average GC content of 37.19%. The complete chloroplast genome has a typical quadripartite structure, including a large single copy (LSC) region (85,829 bp) and a small single copy (SSC) region (18,860 bp), which are separated by a pair of inverted repeats (IRs, 25,771 bp). This plastome contains 129 different genes, including 85 protein-coding genes, 36 tRNA genes, and 8 rRNA genes. The phylogenetic analysis of 20 chloroplast genomes from genera Fragaria, Rosa and Rubus of the family Rosaceae suggested that R. setchuenensis clustered into one clade with the other three species of section Malachobatus Focke, and then grouped with four species of section Idaeobatus Focke, while species from Fragaria and Rosa were classified into a group, separately.

[Root morphological changes in maize and soybean intercropping system under different phosphorus levels]. / 不同磷水平下玉米-å¤§è±†é—´ä½œç³»ç»Ÿæ ¹ç³»å½¢æ€å˜åŒ–.

A pot experiment was conducted to investigate the changes of root morphology and its relationship with P uptake under different P levels (0, 50 and 100 mg P2O5·kg-1, represented by P0, P50 and P100, respectively). The results showed that intercropping significantly changed root morphological parameters of both maize and soybean, and increased the root:shoot ratio in soybean under different P levels. Intercropping significantly increased root length, root surface area, root volume, and root dry weight of maize and soybean by 25.6%, 22.0%, 39.2%, 34.3% and 28.1%, 29.7%, 37.3%, 62.3%, respectively, but significantly decreased the average root diameter by 15.2% and 11.7% compared to corresponding monoculture. The phosphorus uptake equivalent ratio (LERP) was >1, showing P uptake advantage of intercropping and that the LERP were unaffected by P levels. The root morphological changes induced by intercropping were closely related to P uptake improvement. The increases of maize root surface area and soybean root length were the main mechanisms driving efficient P uptake in maize and soybean intercropping. Based on the regression equation, 10% increase of maize root surface area or soybean root length caused 5%-10% increase of phosphorus uptake. P uptake of intercropped maize was not declined under P50 level compared to that of monoculture supplied with P100 level. In conclusion, maize and soybean intercropping has the potential to maintain crop P uptake when reducing application of phosphate fertilizer.

Effects of Applied Ratio of Nitrogen on the Light Environment in the Canopy and Growth, Development and Yield of Wheat When Intercropped.

Changes in the light environment have an important effect on crop growth and yield. To clarify the effects of intercropping and the application of nitrogen on the yield of wheat and light within the crop canopy, the relationship between light and yield and their response to nitrogen fertilizer were studied. In a 2-year field experiment, the characteristics of growth, light, biomass, and yield of wheat were measured using three cropping arrangements (monocropped wheat, monocropped faba beans, and intercropped wheat/faba beans) and four levels of applied nitrogen, in groups termed N0 (0 kg/ha), N1 (90 kg/ha), N2 (180 kg/ha), and N3 (270 kg/ha). The results demonstrated that the application of nitrogen fertilizer increased wheat plant height, spike leaf length and width, and the number of leaves while significantly decreasing wheat canopy light transmittance (LT) and canopy photosynthetic active radiation transmittance (PART), by 7.5-71.1 and 12.7-75.1%, respectively. There was a significantly increased canopy photosynthetic active radiation interception rate (IPAR) of 7.5-97.8% and an increase in biomass of 9.6-38.4%, of which IPAR, biomass, and yield were highest at the N2 level. Compared with monocropping, intercropping increased parameters of wheat growth to varying degrees. Intercropping decreased LT and PART by 10.8-46.4 and 15.7-58.7%, respectively, but increased IPAR by 0.1-66.0%, wheat biomass and yield by 7.5-17.4 and 27.7-47.2%, respectively. The mean yield of intercropped wheat increased by 35.8% over 2 years, while the mean land equivalent ratio (LER) was 1.36, for which a values greater than 1 indicates that wheat and faba bean intercropping is advantageous. Correlation analysis demonstrated that there was a very significant negative correlation between wheat LT and yield, while simultaneously demonstrating a very significant positive correlation between PART and IPAR with yield, indicating that the efficient interception and utilization of light energy in intercropping was the basis for the higher biomass and yield of wheat. In summary, wheat/faba bean intercropping and the application of nitrogen at 180 kg/ha were effective in increasing wheat yield.

Nitrogen supply and intercropping control of Fusarium wilt in faba bean depend on organic acids exuded from the roots.

Fusarium wilt in faba bean (Vicia faba L.) is caused by Fusarium oxysporum f. sp. fabae (FOF), which reduces the yield of crop. We used greenhouse, field and laboratory experiments to evaluate the role of organic acids in the occurrence of Fusarium wilt of faba bean to confirm the mechanism of rational application of nitrogen (N) and intercropping to alleviate Fusarium wilt. We investigated the response of organic acids exuded from the roots of faba bean to different N levels and cropping patterns (monocropping and intercropping with wheat). The results showed that the application of N and intercropping with wheat could control the Fusarium wilt of faba bean, which was closely related to the components and quantity of organic acids exuded from its roots. Among them, tartaric acid and malic acid are the most abundant and important, because they have a significant inhibitory effect on the growth and reproduction of FOF and substantially aid in the control of Fusarium wilt. The application of 90 kg ha-1 of N combined with wheat intercropping significantly controlled the Fusarium wilt and increased the grain yield of faba bean. Our results suggest that 90 kg ha-1 of N combined with intercropping is the most effective way to control Fusarium wilt and should be incorporated into agricultural management practices.

[Quantitative analysis of root morphology and phosphorus absorption in wheat and faba bean intercropping system.] / å°éº¦ä¸Žèš•è±†é—´ä½œä½“ç³»æ ¹ç³»å½¢æ€ä¸Žç£·å¸æ”¶çš„å®šé‡è§£æž.

The intercropping of legume and cereal crops could affect crop roots growth. The relationship among intercropping, root morphology and phosphorus (P) acquisition under different P levels is still unclear. With field experiments and a rhizo-box experiment, we examined the changes of yield, biomass, P acquisition and root morphology of wheat and faba bean under different planting patterns (monocropped wheat, MW; monocropped faba bean, MF; and wheat and faba bean intercropping, W//F) and different P levels. In the rhizo-box experiment, both root weight and root-shoot ratio were increased by 21.2% and 61.5%, respectively, but shoot weight was decreased by 14.6% when wheat intercropped with faba bean. Root P content and P uptake of intercropping wheat (IW) increased by 23.8% and 12.1% when compared to MW. Both shoot and root weight, root-shoot ratio, total root length, and root volume of intercropping faba bean (IF) increased by 16.5%, 47.3%, 24.0%, 3.5%, and 8.4% as compared to MF, respectively, which resulted in higher shoot and root P content and P acquisition of IF. In the field experiment, P uptake by IW decreased by 8.7% at tillering stage, but P acquisition increased by 40.6%, 19.7%, 7.8% and 12.4% at join-ting, heading, filling, and maturity stages as compared to MW. By contrast, P acquisition of IF decreased by 9.8%, 9.0% and 5.2% at flowering, podding, and maturity stages as compared to MF. Partial least squares (PLS) regression analysis showed that root surface area and total volume of wheat and root surface area of faba bean had the greatest contribution to crop P acquisition. Intercropping induced higher root volume and root surface area which resulted in higher P acquisition under low P stress. In conclusion, interspecific interaction amplified the root-soil interface zone and increased P uptake at seedling stage under low P stress, which could contribute to the intercropping advantages at later stage.

Interactive influences of intercropping by nitrogen on flavonoid exudation and nodulation in faba bean.

In order to address the question of how flavonoids affected root nodulation of faba bean in a wheat and faba bean intercropping system, we set up soil and hydroponic experiments comprising two cropping pattern treatments (intercropped and monocropped) and three nitrogen (N) supply treatments at the deficient (50% N), adequate (100% N), and excessive (150% N) levels with three replicates in a randomized complete block design. Across the three N treatments and two experiments, it was frequently observed that intercropping increased but N fertilization decreased the nodule number and nodule dry weight of faba bean. Six types of flavonoids were detected in the faba bean root secretion, but only genistein, hesperetin, and naringenin often had significant correlations with the nodule number and nodule dry weight. Intercropping increased faba bean root secretions of genistein, hesperetin, and naringenin compared to monoculture only at the deficient and adequate N supply levels. The differences in flavonoids of faba bean caused by the intercropped patterns, N supply levels, and their interactions were mainly significant at flowering stage. In conclusion, interspecies and N supply interactively altered the contents and proportions of flavonoids in faba bean root exudations under wheat and faba bean intercropping. These findings provide insight into flavonoids-nodule-yield interactions in cereal and legume intercropping systems.

Cinnamic Acid Inhibited Growth of Faba Bean and Promoted the Incidence of Fusarium Wilt.

To ascertain the role and mechanism of cinnamic acid in the process of soil-borne Fusarium wilt infection with fava bean, we studied the effect of cinnamic acid on the faba bean and Fusarium oxysporum f. fabae (FOF). Our results showed that cinnamic acid treatment affected the physiological resistance of faba bean to FOF after inoculation with the pathogen and enhanced the pathogenicity of the pathogen, which may have led to aggravation of infection by the pathogen and increases in the incidence rates of Fusarium wilt and disease.

[Effect of wheat and faba bean intercropping on root exudation of low molecular weight organic acids].

Pot experiment of wheat and faba bean intercropping was conducted and exudates from wheat and faba bean roots were collected at different growth stages. Low molecular weight organic acids (OA) in root exudates were examined by HPLC. The results showed that wheat and faba bean intercropping significantly increased the total amounts of OA exuded by roots. At tillering (57 d), booting (120 d) and filling stages (142 d), intercropping increased the total amounts of OA in wheat root exudates by 155%, 35.6% and 92.6% respectively, in comparison with that of monoculture wheat (MW). At branching (57 d) and filling stages (142 d), intercropping increased the total amounts of OA in faba bean root exudates by 87.4% and 38.7%, respectively, in comparison with that of monoculture faba bean (MF). Wheat and faba bean intercropping changed the types of OA exuded by roots. At tillering stage, lactic acid was identified in root exudates of intercropping wheat (IW), but not in that of MW. At jointing stage (98 d), citric acid was identified in root exudates of IW, but not in that of MW, and acetic acid was vice versa. At branching stage, acetic acid was identified in root exudates of intercropping faba bean (IF), but not in that of MF, and lactic acid was vice versa. At filling stage, lactic acid was identified in root exudates of IF, but not in that of MF. Wheat and faba bean intercropping increased the OA exudation rate of wheat. At booting stage, the exudation rates of citric and fumaric acid from IW were 179 and 184-times as that of from MW, respectively. At filling stage, the exudation rate of lactic acid from IW was 2.53-times as that from MW. In conclusion, wheat and faba bean intercropping increased the rate and total amount, and changed the types of OA exuded by roots.