Cup Plant (Silphium perfoliatum L.) Biomass as Substitute for Expanded Polystyrene in Bonded Leveling Compounds

Biomass for non-food applications is considered as a substitute for petro-based materials such as expanded polystyrene (EPS). This research analyzes physical properties of an EPS containing commercial bonded leveling compound (BLC) which was substituted with cup plant (Silphium perfoliatum L.) biomass. Cup plant is a high-yielding biomass plant with several ecological benefits that is yet mainly used for biogas production. Furthermore, the high amount of parenchyma in senescent biomass with its EPS-like structure could be a possible substitute for petrochemical foams in lightweight aggregates. The natural variation in parenchyma content of several European cup plant accessions is promising, regarding the development of cultivars with suitable biomass properties for the proposed material use. Two binders with different proportions of cup plant and EPS were used to produce samples of BLC for thermal conductivity and compression strength tests. The compression strength of 0.92 N mm−2 and a thermal conductivity of 84 mW m−1 K−1 were analyzed and comparable to the commercial BLC. The thermal conductivity within the tested borders appears nearly independent of the biomass content. With increasing cup plant content, the shape characteristics of the lightweight aggregate mix changes towards more elongated aggregates. The mechanical strength and thermal conductivity are highly sensitive to the water demand of the biomass. Direct partial substitution of EPS by cup plant appears feasible and could be a part of the decarbonization of the construction sector.

Kochia (Bassia Scoparia) Growth and Fecundity As Influenced By Crop Competition and Weed Density

Kochia [Bassia scoparia (L.) A. J. Scott] represents one the most troublesome weeds in crop production systems in the North American Great Plains. The development of herbicide-resistant B. scoparia populations further exacerbated this problem. More ecologically driven approaches to its control are necessary. This study examined the competitive effects of four crops (sugar beet, soybean, barley, and corn) in combination with B. scoparia densities (3, 13, 24, 47, 94, and 188 plants m-2) on B. scoparia development and seed production across 2 years. Corn and barley had the greatest impact on B. scoparia growth and fecundity. B. scoparia biomass was 87 and 82% lower and seed production was 98 and 96% lower (p<0.001) in corn and barley, respectively, relative to fallow. Corn had greatest effect in reducing B. scoparia biomass and seed production. Barley had greatest effect in delaying B. scoparia flowering which occurred 113 days after B. scoparia emergence (p<0.001). Soybean and sugar beet had the least effect reducing B. scoparia biomass by 70 and 65% and seed production by 84 and 80% (p<0.001), respectively, relative to fallow. Increasing B. scoparia densities resulted in reductions in B. scoparia width, number of primary branches, biomass plant-1, and seeds plant-1 but increased B. scoparia height, biomass m-2, and seeds m-2 (p<0.001) under all cropping treatments except corn. Barley represents the greatest opportunity to impact B. scoparia through reduced fecundity and delayed flowering, with the latter providing a window of opportunity for post-harvest control. The effects observed here were isolated from differences in herbicide practices that are associated with each of these crops, differences that have a dramatic effect on B. scoparia in their own right.

Community social capital in supporting biomass development at The Purwakarta Forest Management Unit, West Java

Biomass plantations are starting to become an option for developing renewable energy sources. Socio-economic problems related to management regulations, trust, and networks in the biomass energy plantations-developing process need to be resolved. This study aims to determine the capacity of community social capital in supporting the development of biomass plantations. The location of the study was at Purwakarta Forest Management Unit (FMU). Data collection was carried out by observation, household surveys using questionnaires, and Focus Group Discussion. Data were analyzed using a descriptive qualitative method. The results show that, in general, the community has strong social capital in building biomass plant partnerships, especially in the aspect of trust. Farmer’s trust in those who assist in the management of biomass plants is relatively high, namely Perhutani, the farmer group leader, and the community leaders. The farmers will be motivated to develop biomass crops if successful examples exist. The social norms and sanctions for farmers in the biomass plant management at Purwakarta FMU are very low, but the community is still obedient to the social norms. The networking ability of farmers is relatively low, so intensive assistance in developing biomass farming must be improved, either in technical assistance or intensive extension.

Mycorrhizal Symbioses Enhance Competitive Weed Growth in Biochar and Nutrient-Amended Soils

Velvetleaf (Abutilon theophrasti) is a highly competitive weed in agroecosystems that is well-studied for its efficient nitrogen (N) acquisition, yet research on its phosphorus (P) uptake is lacking. One pathway may be through symbioses with arbuscular mycorrhizal fungi (AMF) which increase nutrient acquisition. These AMF benefits can be further enhanced by soil amendment with biochar, although effects may vary with different biochar production characteristics. We implemented a fully factorial nutrient and biochar addition experiment in a greenhouse for six months to determine how AMF nutrient uptake impacts plant growth and how these effects vary between two biochar types. We measured total above- and belowground biomass, plant tissue concentration (N and P), AMF colonization and activity rates, and soil media N and P availability. Overall, we observed few statistically significant results, however AMF N uptake may have been more beneficial to velvetleaf than AMF P uptake as evidenced by increased biomass and tissue N concentrations in treatments where N was only accessible by AMF. Additionally, by maintaining root to shoot ratios biochar may have provided plants with N and P (through sorption of nutrients to surfaces or its inherent properties) when nutrients were more difficult to access. We also found variable plant responses across the two biochar types used. Understanding how nutrient and biochar additions can influence weed competition is important for anticipating potential undesirable consequences of novel soil amendments such as biochar.

Effect of Azotobactor and Pseudomonas along with various levels of NPK on growth and flowering of marigold cv. Pusa Narangi Gainda

The experiment was carried at Agriculture Farm, School of Agricultural Sciences and Technology, RIMT University, Mandi Gobindgarh, Punjab, India. This investigation was done to study the effect of different biofertilizers and NPK level on vegetative growth and flowering parameters of marigold cv. Pusa Narangi Gainda during 2019-20. Experiment was laid out in a Randomized Block Design with three replications. Results revealed that, number of leaves/plant (303.98), fresh weight of leaf (4.34 g), dry weight of leaf (1,68 g), leaf biomass/plant (1103.03 g) and stem diameter (1.54 cm) were resulted when plants of marigold treated with treatment T10 (75% NPK + N2 fixer (Azotobactor) + PSB (Pseudomonas) + RDFYM). In concern with flowering parameters, the results revealed that the number of flowers/plant (36.07), fresh weight of flower (6.89 g) and longer flower longevity (34.61 days) were resulted by under T10 (75% NPK + N2 fixer (Azotobactor) + PSB (Pseudomonas) + RDFYM) not with standing, more dry weight of flower (1.91 g) and longer duration of flowering (49.51 days) were recorded under the treatment T9 i.e. 75% NPK + PSB (Pseudomonas).

Phytoextraction of Lead Using a Hedge Plant [Alternanthera bettzickiana (Regel) G. Nicholson]: Physiological and Biochemical Alterations through Bioresource Management

Phytoremediation is a cost-effective and environmentally friendly approach that can be used for the remediation of metals in polluted soil. This study used a hedge plant–calico (Alternanthera bettzickiana (Regel) G. Nicholson) to determine the role of citric acid in lead (Pb) phytoremediation by exposing it to different concentrations of Pb (0, 200, 500, and 1000 mg kg−1) as well as in a combination with citric acid concentration (0, 250, 500 µM). The analysis of variance was applied on results for significant effects of the independent variables on the dependent variables using SPSS (ver10). According to the results, maximum Pb concentration was measured in the upper parts of the plant. An increase in dry weight biomass, plant growth parameters, and photosynthetic contents was observed with the increase of Pb application (200 mg kg−1) in soil while a reduced growth was experienced at higher Pb concentration (1000 mg kg−1). The antioxidant enzymatic activities like superoxide dismutase (SOD) and peroxidase (POD) were enhanced under lower Pb concentration (200, 500 mg kg−1), whereas the reduction occurred at greater metal concentration Pb (1000 mg kg−1). There was a usual reduction in electrolyte leakage (EL) at lower Pb concentration (200, 500 mg kg−1), whereas EL increased at maximum Pb concentration (1000 mg kg−1). We concluded that this hedge plant, A. Bettzickiana, has the greater ability to remediate polluted soils aided with citric acid application.

Immobilization of beneficial microbe Methylobacteriumaminovorans in electrospun nanofibre as potential seed coatings for improving germination and growth of groundnut Arachis hypogaea

Seed inoculation with microbial cells is one of the potential invigouration techniques for enhancing the emergence and growth of plants. Herein, we approached a new localized delivery of beneficial microbial cells (Methylobacterium) by invigorating seeds with electrospun Polyvinyl alcohol (PVA) nanofibre contains microbial cells. Methylobacterium is a growth promoting bacteria recently draws attention in agriculture particularly for drought management. PVA was used in this research because of its electrospinnability and biodegradability. Encapsulation study shows effective immobilization of bacteria cells (Methylorubrum aminovorans) in PVA nanofibre, and SEM and TEM characterization further confirmed the entrapment of microbial cells. The microbial plating enumeration reveals 6.6 x 105 CFU g− 1 of nanofibre to the initial loading population of 1 × 108 CFU. Viability of nanofibre encapsulated bacterial cells under ambient environment found 1.85 × 105 CFU g− 1, 2.2 × 104 CFU g− 1 and 1.2 × 104 CFU g− 1 on 10, 20 and 30 days after storage. In vitro bio-efficacy study exhibits that the seeds coated by PVA nanofibres containing M. aminovorans recorded higher germination, root & shoot length, seedling vigour, drymatter production, plant biomass, plant root volume, nodule numbers and fresh weight of nodules. The data of this study concludes that microbial cells could be immobilized in electrospun nanofibre for extended shelf-life of microbial cells and as effective seed coating for localized delivery.

Conspecific and heterospecific grass litter effects on seedling emergence and growth in ragwort (Jacobaea vulgaris)

Jacobaea vulgaris Gaertn. or common ragwort is a widespread noxious grassland weed that is subject to different regulation measures worldwide. Seedling emergence and growth are the most crucial stages for most plants during their life cycle. Therefore, heterospecific grass or conspecific ragwort litter as well as soil-mediated effects may be of relevance for ragwort control. Our study examines the effects of conspecific and heterospecific litter as well as ragwort conditioned soil on seedling emergence and growth. We conducted pot experiments to estimate the influence of soil conditioning (with, without ragwort), litter type (grass, ragwort, grass-ragwort-mix) and amount (200 g/m², 400 g/m²) on J. vulgaris recruitment. As response parameters, we assessed seedling number, biomass, height and number of seedling leaves. We found that 200 g/m² grass litter led to higher seedling numbers, while litter composed of J. vulgaris reduced seedling emergence. Litter amounts of 400 g/m² had negative effects on the number of seedlings regardless of the litter type. Results for biomass, plant height and leaf number showed opposing patterns to seedling numbers. Seedlings in pots treated with high litter amounts and seedlings in ragwort litter became heavier, grew higher and had more leaves. Significant effects of the soil conditioned by ragwort on seedling emergence and growth were negligible. The study confirms that the amount and composition of litter strongly affect seedling emergence and growth of J. vulgaris. Moreover, while conspecific litter and high litter amounts negatively affected early seedling development in ragwort, those seedlings that survived accumulated more biomass and got taller than seedlings grown in heterospecific or less dense litter. Therefore, ragwort litter has negative effects in ragwort germination, but positive effects in ragwort growth. Thus, leaving ragwort litter on pastures will not reduce ragwort establishment and growth and cannot be used as management tool.