Vegetative compatibility relationships among weakly pathogenic isolates (pathotype E) of Verticillium dahliae

A degree of genetic diversity may exist among Verticillium dahliae isolates within vegetative compatibility groups (VCGs) that bears phytopathological significance and is worth investigating using molecular tools of a higher resolution than VCG characterization. The molecular variability within and among V. dahliae VCGs was studied using 53 artichoke isolates from eastern-central Spain, 96 isolates from cotton, 7 from cotton soil, and 45 from olive trees in countries of the Mediterranean Basin. Isolates were selected to represent the widest available diversity in cotton- and olive-defoliating (D) and -nondefoliating (ND) pathotypes, as well as for VCG. The VCG of 96 cotton and olive isolates was determined in this present study. Molecular variability among V. dahliae isolates was assessed by fluorescent amplified fragment length polymorphism (AFLP) analysis and by polymerase chain reaction (PCR) assays for DNA fragments associated with the D (462 bp) and ND (824 bp) pathotypes, as well as a 334-bp amplicon associated with D pathotype isolates but also present in some VCG2B isolates. Isolates from cotton were in VCG1A, VCG1B, VCG2A, VCG2B, and VCG4B and those from olive trees were in VCG1A, VCG2A, and VCG4B. Artichoke isolates included representatives of VCG1A, VCG2A, VCG2B (including a newly identified VCG2Ba), and VCG4B. AFLP data were used to generate matrixes of genetic distance among isolates for cluster analysis using the neighbor-joining method and for analysis of molecular variance. Results demonstrated that V. dahliae isolates within a VCG subgroup are molecularly similar, to the extent that clustering of isolates correlated with VCG subgroups regardless of the host source and geographic origin. VCGs differed in molecular variability, with the variability being highest in VCG2B and VCG2A. For some AFLP/VCG subgroup clusterings, V. dahliae isolates from artichoke grouped in subclusters clearly distinct from those comprising isolates from cotton and olive trees. In addition, VCG2B isolates from artichoke formed two distinct clusters that correlated with PCR markers of 334 bp (VCG2B(334)) or 824 bp (VCG2B(824)). Artichoke isolates in the VCG2B(334)/2beta(334) cluster were molecularly similar to isolates of VCG1A. The molecular difference found among artichoke isolates in VCG2B correlates with virulence of isolates to artichoke and cotton cultivars demonstrated in a previous study.

Phenolic acids are thought to be beneficial for human health and responsible for vegetables’ health-promoting properties. Free, conjugated, and bound phenolic acids of seven commonly consumed vegetables, including kidney bean, cow pea, snow pea, hyacinth bean, green soy bean, soybean sprouts and daylily, from the regions of Beijing, Hangzhou, and Guangzhou, were identified and quantified by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Three vegetables, namely green soy bean, soybean sprouts, and daylily (Hemerocallis fulva L.), from the Beijing region contained higher concentrations of total phenolic acids than those from the Hangzhou and Guangzhou regions. The results indicated that the phenolic acid content in the seven vegetables appeared to be species-dependent. The highest content of phenolic acids was found in daylily, followed by green soy bean, while the least amounts were identified in kidney bean and hyacinth bean. Typically, phenolic acids are predominantly found in conjugated forms. Principle component analysis (PCA) revealed some key compounds that differentiated the seven vegetables. Green soy bean, compared to the other six vegetables, was characterized by higher levels of syringic acid, ferulic acid, vanillic acid, and sinapic acid. Other compounds, particularly p-coumaric acid, neochlorogenic acid, and caffeic acid, exhibited significantly higher concentrations in daylily. In addition, p-coumaric acid was the characteristic substance in cow pea. Results from this study can contribute to the development of vegetables with specific phytochemicals and health benefits.

Green soybean (Glycine max (L.) Merrill) is a highly nutritious food that is a good source of protein and fiber. However, it is sensitive to low temperatures during the growing season, and enhancing cold tolerance has become a research hotspot for breeding improvement. Background/Objectives: The underlying molecular mechanisms of cold tolerance in green soybean are not well understood. Methods: Here, a comprehensive analysis of transcriptome and metabolome was performed on a cold-tolerant cultivar treated at 10 °C for 24 h. Results: Compared to control groups, we identified 17,011 differentially expressed genes (DEGs) and 129 differentially expressed metabolites (DEMs). The DEGs and DEMs were further subjected to KEGG functional analysis. Finally, 11 metabolites (such as sucrose, lactose, melibiose, and dehydroascorbate) and 17 genes (such as GOLS, GLA, UGDH, and ALDH) were selected as candidates associated with cold tolerance. Notably, the identified metabolites and genes were enriched in two common pathways: ‘galactose metabolism’ and ‘ascorbate and aldarate metabolism’. Conclusions: The findings suggest that green soybean modulates the galactose metabolism and ascorbate and aldarate metabolism pathways to cope with cold stress. This study contributes to a deeper understanding of the complex molecular mechanisms enabling green soybeans to better avoid low-temperature damage.

Vegetative compatibility groups (VCGs) of 12 potato and nine sunflower isolates of Verticillium dahliae were determined using both nitrate non-utilizing (nit) mutants and multiplex-nested-PCR approaches. Based on analysis of nit mutants, most potato isolates showed strong compatibility with VCG 4A and weak compatibility with VCG 4B; one potato isolate was also weakly compatible with VCGs 2A, 2B and 3. Sunflower isolates were more variable and most of them showed weak reactions with VCG 4A and 4B. One sunflower isolate, Vs06-14, was compatible only with VCG3 testers, whereas another isolate, Vs06-20, was compatible with all VCG groups except VCG2A. Vegetative compatibility of four selected isolates, two from potato and two from sunflower, was also investigated after passing them through potato or sunflower for four generations. The VCG of one potato isolate did not change, whereas the other one changed from VCG4B to 4A. One sunflower isolate, initially compatible with both VCG4A and 4B, became incompatible with both. The other sunflower isolate was not compatible with any VCG and remained so. In a second part of this work, multiplex-nested-PCR was carried out to characterize VCGs of the same isolates of V. dahliae. Vegetative compatibility grouping using this approach assigned the V. dahliae isolates to VCG1, 2A, 3 or 4A. Six of the 12 potato isolates and four of the nine sunflower isolates of V. dahliae could not be identified or placed in any VCG group based on PCR results. In the present study, the multiplex-nested-PCR results were confirmed using nit mutants. As such, PCR-based methods will require more specific primers before they can replace the approach based on nit mutants. Current address of A.F. El-Bebany: Department of Plant Pathology, Faculty of Agriculture, Alexandria University, El-Shatby, 21545, Alexandria, Egypt.

Phosphate Uptake and its Incorporation in Some Crop Plants and their Associated Weeds

Verticillium dahliae is one of the most important pathogens causing Verticillium wilt. We studied the characterisation of the genetic relationship between virulence, vegetative compatibility groups (VCGs) and inter-simple sequence repeat (ISSR). A total of 48 V. dahliae isolates, in which 16 are collected from different cotton growing regions in China and 4 isolates belonged to all known VCGs, are used. Half of them were found highly virulent. Mutants (565) were obtained using the nitrate non-utilising mutant. These mutants were grouped into three VCGs: VCG1 (27 isolates), VCG 2 (14 isolates) and VCG 3 (7 isolates). Use of ISSR indicated two main clusters that were related to VCG and virulence. Genetic diversity lineages were obviously correlated to VCGs and ISSRs according to their geographical origin, virulence and ISSR genetic variation. This study could be useful to design and develop effective management strategies beside for quarantine purposes on Verticillium wilt control.

The ecotoxicological effects of Zn2+ on germination and early seedling growth of six pulses were investigated. Seeds of these plants were exposed to seven different concentrations of Zn (0, 0.2, 0.4, 0.8, 1.6, 3.2, and 6.4 mM). The results indicated that root growth and shoot elongation of six pulse plants were more sensitive than seed germination and dry weight for measurement of the toxic of Zn2+ pollutions. Different species show different levels of tolerance to Zn2+ pollution. Vigna radiate and Lathyrus odoratus are the most sensitive to Zn2+, their germination percentage, root growth, shoot elongation and dry weight were significantly lower than other tested species, by contrast, Glycine max and Dumasia villosa are the most resist species, their germination and seedling growth almost were not influenced by Zn2+ pollution significantly comparing the control. There were significantly negatively correlations between seedling growth and increasing concentration of Zn2+ for Glycine max, Lathyrus odoratus and Dumasia villosa. The significantly negative correlations between germination and increasing concentration of Zn2+ were show for Lathyrus odoratus.

Black soybean extract can attenuate thrombosis through inhibition of collagen-induced platelet activation

Verticillium wilt caused by the soil-borne fungus Verticillium dahliae is a devastating disease of cotton, leading to serious loss of lint yield in China. It is important to characterize the prevailing populations of V. dahliae for understanding disease development. In this study, the representative 74 V. dahliae isolates from 28 different cotton regions in three major cotton-production areas in China were identified for their pathotypes, races, vegetative compatibility groups (VCGs) and genetic diversity by specific PCR, amplified fragment length polymorphism (AFLP) and inter simple sequence repeat (ISSR) analysis. Of 74 isolates, 60 isolates (81%) were defoliating (D) pathotype strains, especially in Yellow River/Yantze River Valley region. Seventy isolates belonged to race 2, whereas no race 1 specific fragment was amplified. These isolates were grouped into five VCGs: VCG1A (48), VCG2A/VCG4B (3), VCG2B824 (6), VCG6 (5). The D pathotype and VCG1A isolates have become the dominant strains, moderately and highly virulent isolates were widely distributed in three major cotton-growing areas in China. High level of polymorphic markers was obtained by AFLP and ISSR analyses. Through comparison of the obtained dendrograms by unweighted paired group method with arithmetic averages cluster analysis (UPGMA), the V. dahliae isolates were divided into two major groups and five subgroups. The obvious correlations with the geographic origin of the isolates between AFLP and ISSR were revealed, with significant diversity among V. dahliae isolates. In addition, AFLP dendrogram showed relationships with pathotypes. The results offered a better understanding of the epidemiology of Verticillium wilt in China.

Objective: The study is an attempt to quantitatively measure the presence of Anti-Parkinsons drug Levodopa in members of the family Leguminosae.
 Methods: Reverse phase HPLC, Phytochemical analysis carried out using Bioinformatic tools (ChemMine and Cytoscape). The dried seed samples of Mucuna pruriens (Linn.), Cassia fistula (Linn.), Lathyrus odoratus (Linn.), Glycine max (L. Merr.), and Mimosa pudica (L) were selected for the study of Levodopa, and compared with Tecoma stans from the family Bignoniaceae., and antimicrobial activity was conducted on selected bacteria.
 Results: Mucuna pruriens showed the presence of Levodopa in quantifiable higher quantity i.e., 705.5985 ????g/20 ml, whereas other plant samples contained very less quantity. The antimicrobial activity of the selected plants on E. coli and Bacillus showed positive results.
 Conclusion: The study proves the presence of Anti-Parkinsons drug Levodopa in Mucuna pruriens, whereas absent in the other plants. The selected plants prove the anti-bacterial activity on the selected bacteria.

Vegetative compatibility groups of Japanese isolates of Verticillium dahliae

Belfry, K. D., McNaughton, K. E. and Sikkema, P. H. 2015. Weed control in soybean using pyroxasulfone and sulfentrazone. Can. J. Plant Sci. 95: 1199–1204. Pyroxasulfone and sulfentrazone are new herbicides currently being evaluated for weed control in soybean [Glycine max (L.) Merr.] in Ontario, Canada. Seven experiments were conducted over a 3-yr period (2011 to 2013) at Ridgetown and Exeter, Ontario, to evaluate weed management using pyroxasulfone, sulfentrazone and their tank-mixes relative to the industry standard, imazethapyr plus metribuzin. Tank-mixing pyroxasulfone and sulfentrazone provided up to 97, 46, 60, 100 and 71% control of common lambsquarters (Chenopodium album L.), common ragweed (Ambrosia artemisiifolia L.), green foxtail [Setaria viridis (L.) Beauv.], Powell amaranth [Amaranthus powellii (S.) Wats.] and velvetleaf (Abutilon theophrasti Medic.), respectively, at 2 wk after treatment. Control with pyroxasulfone and sulfentrazone was improved when tank-mixed, relative to application of each herbicide separately. Although control was variable across weed species, no difference in control was identified between pyroxasulfone plus sulfentrazone and imazethapyr plus metribuzin. Soybean yield was up to 2.7, 2.4 and 2.9 t ha−1 for pyroxasulfone, sulfentrazone and pyroxasulfone plus sulfentrazone application, yet imazethapyr plus metribuzin provided the highest yield (3.3 t ha−1). This research demonstrates that pyroxasulfone plus sulfentrazone may be used as a valuable weed control option in soybean; however, weed community composition may limit herbicidal utility.

Public pressure and economic distress have together provided a strong incentive for reduced chemical use in U.S. agriculture. This field study was designed to determine if preplant‐incorporated imazaquin {2‐[4,5‐dihydro‐4‐methyl‐4‐(1‐methylethyl)‐5‐oxo‐1H‐imidazol‐2‐yl]‐3‐quinoline‐carboxylic acid} rates could be reduced from the labeled rates when applied with alachlor [2‐chloro‐N‐(2,6‐diethylphenyl)‐N‐(methoxymethyl) acetamide] without incurring yield penalties due to broadleaf weed infestations. Imazaquin was applied at 0, 47, 93, and 141 g ha−1 in earlyplanted soybean [Glycine max (L.) Merr.] studies in Fayette County in 1989, 1990, and 1991 and in Simpson County (1989), Hardin County (1990), and Hopkins County (1991), Kentucky. Preplant‐incorporated alachlor was followed by postemergence fluazifop‐P‐butyl {butyl(R)‐2‐[4[[5‐(triliuoromethyl)‐2‐pyridinyl]oxy]phenoxy]propanoate} (as needed) to minimize grass competition. Perennial broadleaf weeds were controlled with hand‐wicked glyphosate [isopropylamine salt of N‐(phosphonomethyl) glycine]. Acceptable broadleaf control was obtained at sub‐label imazaquin rates, except for Fayette 1991, where ivyleaf morning‐glory [Ipomoea hederacea (L.) Jacq.] and velvetleaf (Abutilon theophrasti Medic.) were planted. Two studies (Simpson 1989 and Hopkins 1991) showed minimal broadleaf weed pressure at any imazaquin rate; this may have been a result of the early planting dates used. The common lambsquarters (Chenopodium album L.) and Pennsylvania smartweed (Polygonum pennsylvanicum L.), which dominated in Fayette 1989 and 1990, were successfully controlled with 47 g ha−1 imazaquin. While alachlor provides some control for these two species, their competition with soybean was severe without the addition of imazaquin. Producers who can accumulate detailed knowledge of the broadleaf weed species present in their soybean fields could potentially use such information to select herbicides likely to control their broadleaves at sub‐label rates.

Saflufenacil (Sharpen) is a commonly used preplant herbicide for the control of broadleaf weeds in corn (Zea mays) and soybean (Glycine max). Water hardness can influence the efficacy of some herbicides. Field experiments were conducted in Lafayette, IN, in 2012 to determine the influence of water hardness and co‐applied herbicides on the efficacy of saflufenacil. Saflufenacil application with any herbicide provided 12 to 33% higher control of common lambsquarters (Chenopodium album L.) as compared to saflufenacil alone, and saflufenacil with atrazine (Aatrex), clethodim (Select Max), cloransulam‐methyl (FirstRate), dicamba (Clarity), isoxaflutole (Balance Pro), mesotrione (Callisto), metribuzin (Metribuzin 75), paraquat (Gramoxone Inteon), or 2,4‐D (Weedar 64) provided at least 90% control of common lambsquarters at 21 days after treatment (DAT). Tank‐mix of saflufenacil with other herbicides controlled giant ragweed by at least 85%. Regardless of rating intervals, saflufenacil combinations with glufosinate (Ignite) or glyphosate (Roundup Powermax) provided 96% or 100% control of giant foxtail, respectively. Conversely, saflufenacil application with imazaquin and imazethapyr only provided 29 to 65% control of giant foxtail. When saflufenacil was applied alone at 0.36 oz ai/acre and without diammonium sulfate, common lambsquarters control was reduced by water sources having hardness of 310 ppm or 620 ppm as compared to deionized water without diammonium sulfate. When diammonium sulfate was included at 0.17 lb/gal, no differences were observed between water hardness levels. There was no influence of water hardness on saflufenacil efficacy of giant ragweed.

The effect of different levels of cereal rye (Secale cereale L.) residue on common waterhemp (Amaranthus rudis Sauer) and common lambsquarters (Chenopodium album L.) emergence was determined. Cereal rye seeding date had a greater effect on rye biomass accumulation and percent cover than seeding rate. Common waterhemp emergence was equal to or increased in the presence of cereal rye residue in both 2013 and 2014 compared to the control. Common lambsquarters emergence was increased in two treatments in 2014 but was otherwise unaffected by cereal rye. The presence of cereal rye residue increased the time to 10% and 50% emergence of common waterhemp in both years but had less effect on common lambsquarters. The lack of weed emergence suppression seen in these experiments is a concern for cover crop use in Iowa’s conventional cropping systems, while the delay in weed emergence associated with cereal rye residue may be beneficial or detrimental to weed management. Greenhouse trials determined the soil activity of low rates of eleven corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] herbicides on five cover crops: cereal rye (Secale cereale L.), oat (Avena sativa L.), hairy vetch (Vicia villosa Roth), lentil (Lens culinaris Medik.), and radish (Raphanus sativus L.). Cereal rye was the most tolerant cover crop, whereas radish was the most sensitive species. Dry weight of radish was severely reduced by nearly all herbicides, whereas other cover crop species had smaller reductions due to herbicide injury. Root growth of oat was inhibited more by pendimethalin than the other species. Flumetsulam + clopyralid, atrazine, and herbicides containing isoxaflutole caused significant injury to most species studied.