Pre-emergence Stage Research Articles

The Host Range of Fusarium proliferatum in Western Canada.

Fusarium proliferatum is associated with the root rot of many plant species, but knowledge of its impact on western Canadian field crops is limited. This study assessed the host range of this fungus and its effect on plant emergence, plant height, and shoot and root dry weights in repeated greenhouse experiments with wheat, barley, faba beans, peas, lentils, canola, lupine, and soybeans. Infection was confirmed via PCR, and principal component analysis determined the utility of different parameters in assessing host responses. All crops were at least partly susceptible, developing mild to severe disease at the seedling and adult stages, and showing significant reductions in growth. In general, the barley and wheat demonstrated higher tolerances to infection, followed by the faba bean and the pea. The soybean, canola, lupine, and lentil were most susceptible. The canola and the soybean were particularly vulnerable to F. proliferatum at the pre-emergence stage, while infection greatly reduced the lentil's biomass. Reductions in the barley's emergence and other growth parameters, however, occurred only under a high inoculum concentration. Variability in root rot severity among cultivars of the same crop indicated some diversity in host reactions within species. Nonetheless, the absence of fully-resistant crops may pose challenges in managing F. proliferatum in western Canadian cropping systems.

Proteomic characterization of the different stages of seed germination in Cupressus gigantea

Abstract Seed germination is a pivotal period of plant growth and development. This process can be divided into four major stages, swelling absorption, seed coat dehiscence, radicle emergence and radicle elongation. Cupressus gigantea, a tree native to Tibet, China, is characterized by its resistance to stresses such as cold, and drought, and has a high economic and ecological value. Nevertheless, given its unique geographic location, its seeds are difficult to germinate. Therefore, it is crucial to explore the mechanisms involved in seed germination in this species to improve the germination efficiency of its seeds, thereby protecting this high-quality resource. Here, our findings indicate that seed germination was enhanced when exposed to a 6-h/8-h light/dark photoperiod, coupled with a temperature of 20°C. Furthermore, the application of exogenous GA3 (1 mg/ml, about 2.9 mM) stimulated the germination of C. gigantea seeds. Subsequently, proteomics was used to detect changes in protein expression during the four stages of seed germination. We identified 34 differentially expressed proteins (DEPs), including 13 at the radicle pre-emergence stage, and 17 at the radicle elongation stage. These DEPs were classified into eight functional groups, cytoskeletal proteins, energy metabolism, membrane transport, stress response, molecular chaperones, amino acid metabolism, antioxidant system and ABA signalling pathway. Most of them were found to be closely associated with amino acid metabolism. Combined, these findings indicate that, along with temperature and light, exogenous GA3 can increase the germination efficiency of C. gigantea seeds. Our study also offers insights into the changes in protein expression patterns in C. gigantea seeds during germination.

Response of soybean cultivars with different maturation times to pre-emergence herbicides

Herbicide selectivity is the basis for chemical control of weeds; however, it depends on the interactions between herbicide, crop, and edaphoclimatic conditions. The objective of this work was to evaluate the selectivity of herbicides applied at the pre-emergence stage of soybean cultivars with different maturation times grown in different locations. The experiment was conducted under field conditions, in two crop seasons (2019/2020 and 2020/2021), in Lages and Curitibanos, state of Santa Catarina, Brazil. A randomized block experimental design was used, with treatments organized in 4×3 (2019/2020) and 4×4 (2020/2021) factorial arrangements, with four replications. The treatments consisted of interactions between four soybean cultivars: BMX Raio IPRO® (Raio), BMX Zeus IPRO® (Zeus), MONSOY 5947 IPRO® (Monsoy), and BMX Fibra IPRO® (Fibra) and three or four herbicide treatments: control with no herbicides, sulfentrazone + diuron, and diclosulam in 2019/2020; and control with no herbicide, sulfentrazone + diuron, diclosulam, and pyroxasulfone + flumioxazin in 2020/2021. The plots were evaluated for phytotoxicity of herbicides, canopy closure, plant height, stand of plants, number of pods per plant, one-thousand grain weight, and grain yield. The phytotoxicity of herbicides on the soybean plants was mild, under 11%, regardless of the cultivar and growth location. The soybean plants fully recovered from the injuries at 14 days after herbicide application. In Curitibanos, the cultivar Zeus presented higher grain yield in both crop seasons. The herbicide factor showed that sulfentrazone + diuron and diclosulam decreased the grain yield of the cultivars Raio and Zeus in 2019/2020. In the following crop season, only the cultivar Raio presented decreases in grain yield due to the application of diclosulam and pyroxasulfone + flumioxazin. In Lages, the soybean cultivar factor affected the grain yield; the cultivars Monsoy and Fibra were the most productive.

Phytopathological and biochemical impacts of Trichoderma harzianum and certain plant resistance inducers on faba bean root rot disease

BackgroundFaba bean attacked by soil-borne pathogens causing root rot disease. This disease has serious damage to both plant stand and produced yield. The present study aimed to evaluate effectiveness of the bioagents; Trichoderma harzianum and some plant resistance inducers as fungicide alternatives against root rot disease incidence at both pre- and post-emergence growth stages.ResultsUnder open greenhouse conditions, the incidence of faba bean root rot in pre- and post-emergence growth phases was considerably reduced by using six inorganic salts and five antioxidants individually or combining with each other or with the bio-stimulator T. harzianum that exceeded the used fungicide, Rhizolex-T. Application of enervit agitated the highest significant defensive impact during pre-emergence stage versus root rot incidence (5.0%), followed by calcium sulfate and [cysteine + T. harzianum] (6.7%). At post-emergence stage, majority of the treatments completely suppressed (100.0%) root rot incidence, except vitamax plus and the fungicide (Rizolex-T) which expressed by 91.7 and 18.8%, respectively. Duplicate irrigations of 23 treatments after faba bean dressing improved the synthesis of different protein contents with the 2nd of which enhanced higher protein contents than the 1st one, except [T. harzianum + vitamin E + vitamin C + enervit + selenium + vitamax plus], [T. harzianum + vitamax plus] and cysteine. Disodium phosphate induced the highest catalase (CAT) activity (1820.8 and 1677.2 U/g FWt) after both irrigations. [T. harzianum + vitamax plus] and vitamin E induced the highest peroxidase (POD) activity 217.4 and 356.9 U/g FWt after 1st and 2nd irrigations, respectively. Disodium phosphate and [T. harzianum + vitamin E + vitamin C + enervit + selenium + vitamax plus] induced the highest chitinase (CHIA) activity 52.8 and 54.4 U/g FWt after 1st and 2nd irrigations, respectively. Application of disodium phosphate, calcium sulfate, potassium metabisulfite, sodium sulfate, cysteine, [cysteine + potash alum], enervit, vitamin E, [vitamin E + vitamin C + enervit + selenium + vitamax plus], [T. harzianum + enervit], [T. harzianum + selenium], [T. harzianum + vitamin E], [T. harzianum + vitamin E + vitamin C + enervit + selenium + vitamax plus] and vitamin C stimulated the formation of new protein bands on SDS-PAGE after the 2nd irrigation treatment.ConclusionsSuch treatments are considered good and environmentally safe alternatives against root diseases for getting rid of the negative effects of fungicides.

Chemical composition and herbicidal potential of essential oil of Eucalyptus maculata Hook

In continuation of the search of eco-friendly and safe alternatives for chemical pesticide for weeds management, essential oils (EOs) of forestry tree may be a good candidate. Here, the EOs of Eucalyptus maculata were extracted by hydrodistillation and the study of their chemical composition was carried out by GC and GC/MS analysis. The allelopathic effects of E. maculata EOs was tested against two common weeds in Tunisia: Sinapis arvensis (dicot) and Phalaris canariensis (monocot) and Triticum durum as cereal monocot cultivated crop. The application of EOs has been carried out in two stages of growth: pre-emergence and post emergence. Analysis of the EOs resulted in the identification of 46 components representing 97.7% of the total oil. 1.8-Cineole was detected as the principal compound accounted for 42% of the oil totality and oxygenated monoterpenes (61.5%) was the major subclass that characterize E. maculata growing in Tunisia. On pre-emergence stage, Eucalyptus EOs significantly reduced germination and seedling growth of all tested species in a dose dependent manner and the phytotoxic effect of the EOs was differently effective depending on doses and tested species. On post-emergence stage, volatile oil induces a phytotoxic effect against all tested plants, a decrease in relative water content, an increase of relative electrolyte leakage percentage and levels of proline and malondialdehyde contents which explain their significant phytotoxic potential. Thus, E. maculata EOs inhibits germination and seedling growth of tested herbs in pre-emergence stage and post emergence stage, therefore E. maculata EOs shows potential towards weed management.

Microbial Seed Coating-An Emerging Strategy towards Organic Vegetable Production: A Review

New revolutions have been taking place in agriculture since pre-historic times to increase agricultural production and meet the demands of rising population. The last revolution or green revolution has increased the overall production of all agricultural components but has led to several long-term environmental problems. Almost 62% of vegetables and 82% of fruits are found to have pesticide residues, which can affect our health in different ways. This have arisen the fear of eating raw fruits and vegetables and led to sublethal effects on natural enemies and pollinators. So, it is the very need of hour to look for sustainable approaches to control the plant diseases. Most of the plant pathogens are seed borne and disseminated. Thus, they affect the plants during pre-emergence stage or cause seedling damping off resulting in 100% crop loss. Under sustainable practices, microbial seed coating is an evolving precision technology. It enhances the shelf-life and activity of beneficial microbes and thereby decrease the use of harmful chemical pesticides and fertilizers. Natural products such as biochar, chitosan, peat, acacia gum, natural dyes from flowers Phutuka, Polash, Khoyar, Kodam can be used to manufacture microbial seed coats manually. Agribusiness firms Incotec, Novozymes and Monsanto have also led to developing of coated seeds laced with promising microbes. Thus, adoption of microbial seed coating can be a cost effective and efficient strategy in organic horticultural production.

Rice Waste Hydrolyzation at Subcritical Temperature to Produce Bioherbicide to Control Terrestrial Weeds

Thermal anaerobic hydrolyzation process on rice husk with higher lignin content produced organic complexes constituents including phenolic groups. Phenolic groups expose herbicide effects on growing vegetations, where the process in nature mainly require anaerobic condition. The degradation rate in nature is very slow with very low concentration availability. Thermal hydrolyzation is an appropriate choice to produce phenolics herbicide for sustainable pesticide management and application. This study aimed to identify the potency of rice husk extract by thermal hydrolyzation process as an organic herbicide to control terrestrial weeds. The hydrolyzation was processed in 60-90 bars and 280±20 °C for 30±10 minutes. The existence of the phenolic groups in the hydrolysate was considered for generic active ingredients to control weed in the terrestrial ecosystem. Its damage impact was tested on Borreria alata, Eleusine indica, Cyperus kyllingia, Paspalum conjugatum, Asystasia intrusa, and Axonopus compressus. The assay covered the growth at pre-emergence, early post-emergence, and post-emergence growing stages. The rice waste hydrolysate was capable to suppress the growth of the weed growth especially at the pre-emergence stage at 30-64%, and at early post-emergence stages at the suppressing rate of 77-100%. However, the suppressing affectivity is lower at the post-emergence stage which only 17-25%.

Interspecific Usurpation in the Downy Yellowjacket, Vespula flavopilosa (Hymenoptera: Vespidae)

We report 12 new observations of parasitically-founded Vespula flavopilosa colonies. Of these, 4 nests were identified directly by having been found in the pre-emergence stage, whereby only the resident queen was seen foraging before the presence of the first workers. Seven nests were found in the early phases of worker production, wherein the queen and first workers were foraging simultaneously, or nests were observed containing workers of both the host V. maculifrons and parasite V. flavopilosa freely foraging together. A twelfth nest, collected later in the season, appeared to have been the result of a usurpation of a V. germanica nest, based on gray paper found in the central cores of the first three combs of the nest. This represents the first report of V. flavopilosa utilizing the introduced V. germanica as a host species. These observations cover a wide part of the species' range, and imply that V. flavopilosa is a frequent temporary social parasite. Furthermore, this behavior appears to be obligatory since an incipient nest founded unequivocally by a V. flavopilosa queen has not been recorded.

Efficacy, Energy Budgeting, and Carbon Footprints of Weed Management in Blackgram (Vigna mungo L.)

Weed management in blackgram is one of the most efficient ways to improve its yield, as uncontrolled weed growth causes a significant decrease in crop yield. A field experiment was performed at Berthin, Himachal Pradesh, India, to investigate the efficacy, energy use efficiency (EUE), and carbon footprints of weed management tactics. Twelve weed control treatments were tested applied alone or in combination at pre and post emergence stages. The most prominent weeds were Cyperus iria, Dactyloctenium aegyptium, and Echinochloa colona, which caused a 68.1% loss in unweeded conditions. The application of weed control treatments reduced the weed count at 60 DAS from around 50% to 90%. The most efficient weed control treatment was pre-emergence (PRE) use of ready mix imazethapyr 35% + imazamox 35% WG @ 80 g ha−1, which resulted in a minimum weed infestation (i.e., weed count and weed biomass) and consequently highest yield. Its efficacy in weed control treatment was on par with PRE use of ready mix imazethapyr (35%) + imazamox (35% WG @ 70 g ha−1. Maximum energy use efficiency was also obtained upon PRE use of imazethapyr (35%) + imazamox (35% WG) @ 80 g ha−1 (8.27), trailed by PRE use of imazethapyr + imazamox @ 70 g ha−1 (7.84), mainly because of the higher yield obtained in these treatments which shows their efficiency in energy conversion. The carbon footprints were observed to be the lowest in ready mix combination of imazethapyr (35%) + imazamox (35% WG) applied at 80 g ha−1 (0.11 kg CE kg−1 yield), followed by imazethapyr (35%) + imazamox (35% WG) applied at 70 g ha−1 (0.12 kg CE kg−1 yield), as it resulted in the lowest emission per unit output production.

Biochemical and hormonal changes associated with root growth restriction under cadmium stress during maize (Zea mays L.) pre-emergence

Cadmium (Cd) pollution of agricultural soils is a growing global concern. Plant growth restriction is the main visible symptom of Cd toxicity, and this metal may be particularly harmful to the preformed, seminal root during the pre-emergence stage. In the present study, we focused on Cd phytotoxicity in seminal root growth, nutrient composition, redox status, and hormone homeostasis during the pre-emergence stage of maize (Zea mays L) plants, distinguishing between the root apex and the remaining root tissue. After 72 h of metal exposure (50 and 100 µM CdCl2), root length and biomass, as well as Ca, Fe, Mg, and Mn contents, were diminished. A redox imbalance was evidenced by changes in peroxidase activities and the ascorbate–dehydroascorbate ratio decreased in both root parts. There were fewer carbonylated proteins in both root fractions after exposure to 50 µM Cd, compared to 100 µM Cd, which was related to increased 20S proteasome activities. Cd incremented ABA, IAA, and SA contents, but drastically reduced the biologically active gibberellin GA4 and the conjugate jasmonoyl-isoleucine (JA-Ile). We demonstrated that the whole root tissue is involved in the maize response to Cd stress, which entails redox and hormonal rearrangements, probably directed to widen the plant defense lines at the expense of root growth.

Characterization of CYCLOPHILLIN38 shows that a photosynthesis-derived systemic signal controls lateral root emergence.

Photosynthesis in leaves generates fixed-carbon resources and essential metabolites that support sink tissues, such as roots. Two of these metabolites, sucrose and auxin, promote growth in root systems, but the explicit connection between photosynthetic activity and control of root architecture has not been explored. Through a mutant screen to identify pathways regulating root system architecture, we identified a mutation in the Arabidopsis thaliana CYCLOPHILIN 38 (CYP38) gene, which causes accumulation of pre-emergent stage lateral roots. CYP38 was previously reported to stabilize photosystem II (PSII) in chloroplasts. CYP38 expression is enriched in shoots, and grafting experiments show that the gene acts non-cell-autonomously to promote lateral root emergence. Growth of wild-type plants under low-light conditions phenocopies the cyp38 lateral root emergence defect, as does the inhibition of PSII-dependent electron transport or Nicotinamide adenine dinucleotide phosphate (NADPH) production. Importantly, these perturbations to photosynthetic activity rapidly suppress lateral root emergence, which is separate from their effects on shoot size. Supplementary exogenous sucrose largely rescued primary root (PR) growth in cyp38, but not lateral root growth. Auxin (indole-3-acetic acid (IAA)) biosynthesis from tryptophan is dependent on reductant generated during photosynthesis. Consistently, we found that wild-type seedlings grown under low light and cyp38 mutants have highly diminished levels of IAA in root tissues. IAA treatment rescued the cyp38 lateral root defect, revealing that photosynthesis promotes lateral root emergence partly through IAA biosynthesis. These data directly confirm the importance of CYP38-dependent photosynthetic activity in supporting root growth, and define the specific contributions of two metabolites in refining root architecture under light-limited conditions.

Production and characterization of xylanase from pomegranate peel by Chaetomium globosum and its application on bean under greenhouse condition

Background and objectiveThe main objective of the present study was production of xylanase from different agricultural wastes using Chaetomium globosum on pomegranate waste, isolation of fungi associated with some legumes seeds, and studied the effect of safe product which obtained from xylanse under laboratory and greenhouse conditions on bean seeds.Results and discussionDifferent agricultural wastes were tested for xylanase production by Ch. globosum; from them, pomegranate peel was most effective at concentration 40 g/l using 2 disks 6 mm in diameter after 7-day incubation period produces 1398.34 U/ml. Addition of calcium chloride increases xylanase activity to 1469.40 U/ml. The crude xylanase activity was active after 20 min of starting of reaction at 6.6 pH, and 40 °C of the reaction mixture produces 1587.27 U/ml. Xylanse is still active at 40 °C for 30 min. Seeds of some legumes were examined for seed borne mycoflora by the agar plate method. The most common fungi were Fusarium solani, Rhizoctonia solani, and Macrophomina phaseolina.Testing of crude xylanase as biocide was more effective in reduction of linear growth of some pathogenic fungi also applied the biocide as seed treatment of bean. Seed coating with biocide gave significant protection to emerge bean seeds against invasion of pathogenic fungi at the pre-emergence stage. Seed coating recorded more than 50% protection compared with the untreated control.ConclusionProduction of xylanase from pomegranate peel wastes using Chaetomium globosum under optimum conditions. Testing crude xylanase after optimization as an effective biocide.

The residual effect of metsulfuron on soybean tolerant and non-tolerant to sulfonylureas

Metsulfuron is widely used for weed management; however, the residual effect on STS soybean cultivars is unknown. The objective of this work was to evaluate the residual effect of the herbicide metsulfuron on the BMX Garra RR2/STS and M 6410 IPRO (non-STS) soybean cultivars. The herbicide metsulfuron was applied at a rate of 2.4 g a.i. ha-1, in pre-planting of soybean plants. The design was completely randomized in a 2×5 factorial scheme with four replications (first factor: two soybean cultivars - STS and no-STS; second factor: five periods between metsulfuron application and soybean sowing - 0, 15, 30, 45, and 60 days). At 7, 14, 21, and 28 days after sowing (DAS), an emergency evaluation of the soybean seedlings was performed; at 28 DAS, height and dry mass of the shoot were evaluated. The height averages for the STS cultivar were higher than the values of the no-STS cultivar. The average dry mass of soybean plants was higher in the STS cultivar at 0, 15, and 30 days between application and sowing. No differences were observed between the cultivars for the periods of 45 and 60 days, for average dry mass. The BMX soybean cultivar Garra RR2/STS was potentially tolerant for the pre-sowing application of the herbicide metsulfuron. The cultivar of M 6410 IPRO (nonSTS) was affected in its initial development by the metsulfuron application during the pre-emergence stage; however, the 60-day metsulfuron application was safer, and therefore, it is recommended to perform the herbicide application in that interval.

Comparative analyses of plantain vivoplants responses to different clam shells and Tithonia diversifolia treatments in terms of growth promotion and induced resistance against Mycosphaerella fijiensis

The seeds availability and quality are the main constraints for agricultural explosion of plantain productivity in sub-Saharan Africa countries. Plantain vivoplants were generated and submitted to different treatments in the nursery, the plant responses were analysed and compared in other to determine the best treatment influencing the growth promotion and induced resistance to Mycosphaerella fijiensis. Plantain explants and vivoplants were treated with five different treatments: clam shells powder (T1), clam shells and Tithonia diversifolia powder (T2), Tithonia diversifolia flakes (T3), Tithonia diversifolia mulch (T4), Tithonia diversifolia liquid extract (T5). The treatments were applied by their incorporation in the substrate (T1, T2, T3 and T4) or by watering of the whole plant (T5). The germination rate was evaluated and recorded in the greenhouse at the germination and pre-emergence stage, followed by the agromorphological measurements on the vivoplants and their inoculation with Mycosphaerella fijiensis in the shade at the vegetative growth stage. Biochemical analysis was done on the vivoplants leaves tissues. The vivoplants respond positively to all the treatments by a quick germination and emergence, coupled with an important biomarker’s accumulation (total proteins and phenolics). It turns out that the best treatment was T5 (T. diversifolia liquid extract), followed by T4 (T. diversifolia mulch). However, depending on the expected response in the vivoplants, all these treatments have proven to be impactful. Therefore, a combination of Tithonia diversifolia liquid extract (T5) with clams’ shells (T1) could be useful to boost the production at low cost and without chemical inputs of large amount of improved vigorous (clean and less susceptible) planting material, impacting thus the food security and poverty alleviation.

Disruption of <i>CYCLOPHILIN 38</i> Function Reveals a Photosynthesis-Dependent Systemic Signal Controlling Lateral Root Emergence

Photosynthesis in leaves generates the fixed-carbon resources and essential metabolites that support sink tissues, such as roots. One of these products, sucrose, is known to promote primary root growth, but it is not clear what other molecules may be involved and whether other stages of root system development are affected by photosynthate levels. Through a mutant screen to identify pathways regulating root system architecture, we identified a mutation in the CYCLOPHILIN 38 (CYP38) gene, which causes an accumulation of pre-emergent stage lateral roots, with a minor effect on primary root growth. CYP38 was previously reported to maintain the stability of Photosystem II (PSII) in chloroplasts. CYP38 expression is enriched in the shoot and grafting experiments show that the gene acts non-cell autonomously to promote lateral root emergence. Growth of wild-type plants under low light conditions phenocopied the cyp38 lateral root emergence phenotype as did the inhibition of PSII-dependent electron transport or NADPH production. Importantly, the cyp38 root phenotype is not rescued by exogenous sucrose, suggesting the involvement of another metabolite. Auxin (IAA) is an essential hormone promoting root growth and its biosynthesis from tryptophan is dependent on reductant generated during photosynthesis. Both WT seedlings grown under low light and cyp38 mutants have highly diminished levels of IAA in root tissues. The cyp38 lateral root defect is rescued by IAA treatment, revealing that photosynthesis promotes lateral root emergence partly through IAA biosynthesis. Metabolomic profiling shows that the accumulation of several defense-related metabolites are also photosynthesis-dependent, suggesting that the regulation of a number of energy-intensive pathways are down-regulated when light becomes limiting.

Many are called but few are chosen: the emergence of Latino congressional candidates

ABSTRACT Prior work has shown that Latino candidates do not under-perform compared to other candidates, and that Latino underrepresentation is a function of supply rather than demand (Juenke, Eric Gonzalez. 2014. “Ignorance Is Bias: The Effect of Latino Losers on Models of Latino Representation.” American Journal of Political Science 58 (3): 593–603; Juenke, Eric Gonzalez, and Paru Shah. 2015. “Not the Usual Story: the Effect of Candidate Supply on Models of Latino Descriptive Representation.” Politics, Groups, and Identities 3 (3): 438–453). Building on this work we investigate what factors influence the prospects of Latino candidates from the supply side. Examining candidate emergence from the supply side requires that we examine not only the winners and losers, but also those who could have entered a pool of candidates but did not. Using an original dataset of latent and primary candidates running for U.S. House seats from 2004 to 2014, we show that Latino candidacy at the pre-emergence stage is sensitive to potential challengers and that party elites under-support Latino candidates relative to others. Latinos are predicted to receive fewer endorsements than non-Latinos, and those endorsements influence candidates’ chances of winning office. Our findings suggest that the poor integration of Latinos into partisan networks is largely responsible for their limited presence in candidate pools and elected office.

Embracing entrepreneurial action through effectuation in social enterprise

PurposeMainstream entrepreneurship research tends to adopt either the causation or effectuation perspective in their studies. Yet, the social enterprise literature has largely focussed on the bricolage perspective to explain social entrepreneurial action. The authors argue that when investigating legitimacy driven opportunity pursuit of an enterprise’s pre-emergence stage, all three perspectives of causation, effectuation and bricolage are required. The purpose of this paper was to address the research question how does effectuation determine entrepreneurial action in the pre-emergence of a social enterprise?Design/methodology/approachAn in-depth single case study approach was used based on the data provided by the founding entrepreneur of Good-Faith Learning social enterprise in Australia.FindingsThe results demonstrated the complementary evolution of the three perspectives. In the following sequence, the effectuation, causation and bricolage actions were identified during the pre-emergence stage of the Good-Faith Learning social enterprise. Specifically, the input–process–output perspective of the study confirmed that the initial stage reflects on the effectual means linked to the causation-based strong articulation of the social vision and mission. The process stage dominates the bricolage approach to resourcing leading to effectual outcomes subsequently. Further, the specific actions of the pre-emergence stage are comprised legitimacy driven symbolic management approaches conveying the entrepreneur’s credibility and commitment, professional organising through website, gut-instinct based team selection, and organisational achievement.Research limitations/implicationsThe future research may conduct multiple case study analysis with multiple respondents to observe the consistency or deviations of the patterns identified in this study.Originality/valueThis single case study demonstrates the complementary existence of causation, effectuation and bricolage elements in entrepreneurial actions in a single social enterprise context and advances the social entrepreneurship literature.

The Influence of Herbicide Underdosage on the Composition and Diversity of Weeds in Oilseed Rape (Brassica napus L. var. oleifera D.C.) Mediterranean Fields

Weed flora is considered harmful for crop growth and yield, but it is fundamental for preserving biodiversity in agroecosystems. Two three-year trials were conducted in Italy (two different sites) to assess the effect of six herbicide treatments on the weed flora structure of an oilseed rape crop. We applied metazachlor during the pre-emergence stage at 25%, 50%, 75%, and 100% of the labelled dose (M25, M50, M75, M100); trifluralin (during the first growing season); post-emergence treatment (PE); and a weedy control (W). Species richness, and diversity indices were used to characterize weed flora composition and to evaluate the effect of herbicide treatments on the considered variables. Results highlighted that the weed community is characterized by a higher diversity in underdosed than in M100 treated plots. Raphanus raphanistrum and Sinapis arvensis were the most common species in M75 and M100 treatments in both sites, while more weed species were detected in underdosed treatments and in weedy plots. The highest Shannon index values were observed in the underdosed treatments. In general, only a slightly similar trend was observed between sites, weed abundance and diversity being positively affected both by low-input herbicide management and by environmental factors (e.g., pedoclimatic situation and previous crop).

Abiotic stress modulates root patterning via ABA-regulated microRNA expression in the endodermis initials.

Patterning of the root xylem into protoxylem (PX) and metaxylem is regulated by auxin-cytokinin signaling and microRNA miR165a/166b-mediated suppression of genes encoding Class III HOMEODOMAIN LEU-ZIPPER (HD-ZIPIII) proteins. We found that, in Arabidopsis, osmotic stress via core abscisic acid (ABA) signaling in meristematic endodermal cells induces differentiation of PX in radial and longitudinal axes in association with increased VND7 expression. Similarly, in tomato, ABA enhanced PX differentiation longitudinally and radially, indicating an evolutionarily conserved mechanism. ABA increased expression of miR165a/166b and reduced expression of the miR165a/166b repressor ZWILLE (ZLL) (also known as ARGONAUTE10), resulting in reduced levels of all five HD-ZIPIII RNAs. ABA treatments failed to induce additional PX files in a miR165a/166b-resistant PHB mutant, phb1-d, and in scr and shr mutants, in which miR165a/166b expression is strongly reduced. Thus, ABA regulates xylem patterning and maturation via miR165a/166b-regulated expression of HD-ZIPIII mRNAs and associated VND7 levels. In lateral root initials, ABA induced an increase in miR165a levels in endodermal precursors and inhibited their reduction in the future quiescent center specifically at pre-emergence stage. Hence, ABA-induced inhibition of lateral root is associated with reduced HD-ZIPIII levels.

Antifungal Activity of Spearmint and Peppermint Essential Oils against Macrophomina Root Rot of Cotton

Essential oils as natural antifungal substances one of the alternative methods for plant disease control. The present study was conducted during 2015 and 2016 to investigate the antifungal activity and oil constituents of volatile oils from spearmint (Mentha viridis L.)and peppermint( Mentha piperita L.) against cotton root rot pathogen (Macrophomina phaseolina). Gas chromatographic analysis revealed that spearmint volatile oilwas constituted by carvone (60.16%) as a major component followed by 1,8 cineole (8.67%), limonene (7.40 %), dihydro carvone (5.86 %), β- ocimene (4.29%) and pulegone (3.23%). While peppermint volatile oilwas rich in menthone (46.52%), menthol (25.88%), limonene (7.72%) menthyl acetate (3.90%), iso menthol (2.10%) and sabinene (2.03%). Both essential oils with different concentrations were evaluated in vitro against three fungus isolates. The two tested oils exhibited 89.55 inhibition percent for the crude oils, against all the tested fungal isolates. Moreover, it was noticed that as oil concentrations decreased, the inhibitory effect also decreased. At the same time, a highly significant effect of oils at all concentrations was observed during sclerotial formation (number and size). The use of essential oils as seed treatment exhibited a highly significant reduction in disease incidence of cotton which has been artificially infested with root rot patho­gen, compared to fungicide and untreated control treat­ments under the greenhouse conditions. This reduction was calculated to be between 4.56 and 100% compared with a 26.67% reduction with the utilization of Topsin M treatment at the pre-emergence stage. At the post-emergence stage, all applied treat­ments were able to decrease the percentage of root-rot incidence. Reduction ranged between 66.67 and 100% over the untreated control. Reduction in disease incidence was reflected in a survival plants increase of 34.62–96.17% and 73.09–126.9% for spearmint and peppermint volatile oils, receptively. Results in the current study demonstrated, that application of peppermint essential oils has an observer influence on the plant growth (plant height), which differ significantly from this of spearmint oil.