Search

This study aims to characterise the so-called Sialkoti paper used to produce Pahari drawings preserved today in the Wereldmuseum in Leiden (Netherlands) (WML). These works originate from the Punjab Hills in India (today Himachal Pradesh) and are commonly known as 'Pahari miniature paintings'. The paper upon which these drawings are executed is said to have been produced in Sialkot during the eighteenth and nineteenth centuries when papermaking was an integral part of an overall regional economy correlated with other sectors such as agriculture and the textile industry. Although the term Sialkoti refers to identified papermills in Sialkot (now Pakistan), the paper from this region is yet to be subjected to a systematic study. This article therefore explores the paper(s) in question through macro- and microscopic observations of structure, pulp and fibres. The study of historical sources, complemented by the analysis of paper samples and fibre identification, has revealed that the pulp would have been prepared from a variety of manufactured products using different technologies, such as rags, cloth, mats, rope and other plant-based materials made from local bast fibres which, once tattered, were recycled to prepare the pulp. Microscopic study reveals that a variety of fibre combinations under different conditions and processing steps were used, in particular sunn hemp fibre (Crotalaria juncea L.), a plant species that has until now rarely been identified in historical paper. In addition, the presence of kenaf and jute fibres, as well as a significant quantity of cotton fibres, have also been demonstrated. To overcome the lack of comparative materials, our work was supported by a comparative study of several materials made from sunn hemp now held in the Ethnobotany Collection at Kew Gardens. Samples were taken from these materials and provided useful reference micrographs for the identification of the WML samples. The quality of the paper used by Pahari artists, as well as the raw materials available and their processing, are discussed in detail. Putting all the data, including technical and historical information into perspective, we conclude that the Pahari artists used a paper of inferior quality compared to other types of paper used for other purposes such as the creation of illuminated manuscripts in the Punjab plains. This study therefore provides useful analytical and material evidence that complements previous historical, technical and anthropological studies. [ABSTRACT FROM AUTHOR]

Untreated and alkali-treated Sunn hemp hessian cloth-reinforced high-density polyethylene (HDPE) composites were prepared by the compression molding method. The fabricated composites contained 40, 45, 50, 55, 60, and 65wt% fiber contents and were optimized. 55wt% fiber contents reinforced composites showed better mechanical properties. This composite was alkali treated and irradiated under gamma-ray at doses 2.5‒7.5 kGy at the rate of 6 kGy/h. The X-ray diffraction (XRD) result indicates that the crystallinity of the alkali-treated Sunn hemp-reinforced HDPE composites shows a higher value than those of untreated and irradiated composites. Better adhesion between fiber and matrix was observed from surface micrographs. Fourier-transform infrared (FTIR) spectroscopy reveals cross-linking between fiber and matrix. The water intake properties of irradiated composite show more hydrophobic nature than that of untreated and alkali-treated composites. The tensile strength of the gamma-ray irradiated composites are 20% and 33% greater than that of untreated and alkali-treated composites. Similar results are found for Young's modulus. At a certain dose of 5 kGy, the irradiated composites show improved thermal, mechanical, and structural properties than untreated and alkali-treated composites. [ABSTRACT FROM AUTHOR]

Abstract This study aims to characterise the so-called Sialkoti paper used to produce Pahari drawings preserved today in the Wereldmuseum in Leiden (Netherlands) (WML). These works originate from the Punjab Hills in India (today Himachal Pradesh) and are commonly known as ‘Pahari miniature paintings’. The paper upon which these drawings are executed is said to have been produced in Sialkot during the eighteenth and nineteenth centuries when papermaking was an integral part of an overall regional economy correlated with other sectors such as agriculture and the textile industry. Although the term Sialkoti refers to identified papermills in Sialkot (now Pakistan), the paper from this region is yet to be subjected to a systematic study. This article therefore explores the paper(s) in question through macro- and microscopic observations of structure, pulp and fibres. The study of historical sources, complemented by the analysis of paper samples and fibre identification, has revealed that the pulp would have been prepared from a variety of manufactured products using different technologies, such as rags, cloth, mats, rope and other plant-based materials made from local bast fibres which, once tattered, were recycled to prepare the pulp. Microscopic study reveals that a variety of fibre combinations under different conditions and processing steps were used, in particular sunn hemp fibre (Crotalaria juncea L.), a plant species that has until now rarely been identified in historical paper. In addition, the presence of kenaf and jute fibres, as well as a significant quantity of cotton fibres, have also been demonstrated. To overcome the lack of comparative materials, our work was supported by a comparative study of several materials made from sunn hemp now held in the Ethnobotany Collection at Kew Gardens. Samples were taken from these materials and provided useful reference micrographs for the identification of the WML samples. The quality of the paper used by Pahari artists, as well as the raw materials available and their processing, are discussed in detail. Putting all the data, including technical and historical information into perspective, we conclude that the Pahari artists used a paper of inferior quality compared to other types of paper used for other purposes such as the creation of illuminated manuscripts in the Punjab plains. This study therefore provides useful analytical and material evidence that complements previous historical, technical and anthropological studies.

Among the species of the genus Crotalaria L., Crotalaria juncea is the only cover crop cultivated for its fiber. The quality of the latter depends on the nutritional conditions, accumulation of biophilic elements in the biomass, and synthesis of proteinogenic amino acids. Thus, the purpose of this study was a qualitative and quantitative assessment of the green harvest at the active flowering stage, before the bean formation phase, when the entire biochemical cycle of the plant is reconfigured, and the biochemical indicators are maximum. The plants were grown for 140 days (from April 22 to September 9, 2023) in protected soil conditions. The experimental design consisted of two units of 50 plants each: in the first (control) unit, plants were grown in a soil mixture without any additives; in the second one, they were treated three times during the growing season with an organic suspension of humic acids (1000 ppm) obtained from sapropel (Pskov oblast, UDHSS) by applying it when watering at the root. The soil substrate in both cases was typical chernozem (Kamennaya Steppe Nature Reserve, Voronezh oblast, 51°01′41.6″ N, 40°43′39.3″ E) with a 20% addition of volcanic zeolite. Over the course of every 14 days, morphometric trends of the crop growth (height and dry biomass) were systematically recorded with the removal of five cultivars from each unit of options. After 140 days, the remaining five replicates per option were subjected to biochemical analysis by inductively coupled plasma mass spectrometry (ICP-MS) and high-performance liquid chromatography (HPLC) using the 7500 and LC 1200 devices (Agilent Technologies, United States) according to the manufacturer's method. Treatment with UDHSS increased productivity and shoot height by 51.1% and 11.3%, respectively. The microelement concentration order in the dry biomass was as follows: Na > K > Ca > S > P > Mg in the control option and Na > K > Ca > Mg > P > S in the UDHSS option, while the microelement export was observed as Fe > Mn > Zn > Ba > B > Cu > Mo and Fe > Mn > B > Zn > Ba > Cu > Mo. In total, the increase was more evident in the microelement accumulation due to a twofold increase in the concentration of iron ions. As for amino acids, L-lysine, L-glycine, L-glutamine, and L-tyrosine became higher. The first three are structural components of biological tissues indirectly indicative of an increase in the fiber strength of the plant culture. [ABSTRACT FROM AUTHOR]

Salt stress exerts adverse effects on yield by inhibiting or delaying seed germination and impeding seedling growth. Additionally, different salt concentrations have adverse effects on plant wet and dry weight and stem and shoot development. Crotalaria juncea L., the fastest-growing species within the Crotalaria genus, demonstrates a high degree of adaptability to both tropical and subtropical climates. To assess the tolerance of sunn hemp to salinity during the germination and early seedling stages, several indicators were determined at different (0, 50, 100, 150, 200, 250, and 300 mM) salt concentrations. Germination was conspicuously absent at salt concentrations of 250 mM and 300 mM. Notably, seedling characteristics, such as shoot length, root length, root fresh weight, seedling fresh weight, retention capability of the shoot, and the relative water content, experienced adverse effects with escalating salt concentrations. Intriguingly, the apex of seedling and root dry weights manifested at the pinnacle of salt concentration at 200 mM. Despite the discernible influence of heightened salt concentrations during the nascent seedling stage, the tolerance index was quantified at 100 mM, 150 mM, and 200 mM. Analyzing the study results through the lens of macro-minerals revealed an augmentation in Na and Cl content concomitant with increasing salt concentrations. [ABSTRACT FROM AUTHOR]

In this work, it was obtained and characterized a gum extracted from Crotalaria Juncea seeds. For this purpose, 2³ factorial experimental design was performed to generate significant and predictive first-order mathematical models. It was evaluated how the independent variables used in the extraction processes (temperature, NaCl concentration and time) influenced the dependent variables (yield, organic matter content and viscosity). The yields were between 11 and 36 w/w% and the molar masses of the gum were between 7.499 × 105 and 1.448 × 106 g/mol, with average organic matter content of 72.76 w/w%. The characterization analyses confirmed the predominance of a galactomannan polysaccharide. Brine samples containing the gum with different ion concentrations had a pseudoplastic rheological profile, without alteration of the viscosity values with variation of the salt concentration in the brine, but the viscosity decreased with rising temperature. [ABSTRACT FROM AUTHOR]

The management adopted in the establishment and replanting of sugarcane fields, with conventional tillage followed by fallow, is one of the main causes of soil quality degradation. In this context, the soil quality index (SQI) is an important tool to guide the use of more sustainable practices and management. This study aimed to monitor the effect of different cover crops in association with different tillage systems on sugarcane yield based on key indicators and an SQI developed using the Soil Management Assessment Framework (SMAF). The experiment was carried out on a sugarcane expansion area located in the municipality of Ibitinga, São Paulo, Brazil. The following soil physical and chemical attributes were analyzed: soil bulk density, macroaggregates, available phosphorus and potassium. Soil carbon content was also analyzed and used to calculate the SQI. Productivity over the 4 years of sugarcane cultivation was also analyzed. The use of subsoilers for soil tillage proved efficient in managing compaction by providing lower soil bulk density values in the first years of cultivation (1.59 and 1.63 g cm−3); however, these effects occurred in the short term with a 10% increase in later years. The use of millet in association with subsoiling showed the best results for soil quality (0.59), reflected in the maintenance of yields at 100 Mg ha−1 over time. Thus, our study reinforces the importance of using soil conservation systems in sugarcane replanting areas to achieve production longevity. [ABSTRACT FROM AUTHOR]

Copyright of Environmental & Social Management Journal / Revista de Gestão Social e Ambiental is the property of Environmental & Social Management Journal 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 Green manure (GM) may reduce the use of chemical fertilizers, been an ecologically appropriate strategy to cultivation of medicinal plants. Crotalaria juncea, is one of the most used because it adapts to different climatic and high nitrogen content. Origanum vulgare. is widely used in cooking, pharmaceutical, cosmetic industries and food products. The objectives of this study were to evaluate the GM on biomass, essential oil (EO), phenolic and antioxidant. The experiment consisted: control; 150, 300, 450, and 600 g (Sh= leaves+steam) more 200 g roots (R); 600 g aerial part; 200 g roots; and soil with 300 g cattle manure per pot. The highest dry weights were observed in the presence of GM and cattle manure (90 days). The control had an EO production 75% lower in relation to the dose of 450 g GM (Sh+R). Principal component analysis showed that GM and cattle manure positively influenced the dry weight, content, yield, and EO constituents, and total flavonoids. The GM contributed to the accumulation of the major EO compounds (trans-sabinene hydrate, thymol, terpinen-4-ol). The GM management may be beneficial for cultivating, because it can increase the production of biomass and the active components, in addition to being an inexpensive resource.

Many ground beetle species (Coleoptera: Carabidae) prey on noctuid larvae and pupae. Therefore, agricultural practices that maintain or even enhance carabid populations have the potential to reduce noctuid pest populations through predation. One such pest is the fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), a migratory pest of row, turf, and vegetable crops. Before migrating in spring from southern Florida and southern Texas, it feeds and develops on cover crops such as field corn and sorghum-sudangrass and expands its populations. Here we sampled the species and density of carabid populations that were active in cover crops with differing capacity to support fall armyworm development. Three cover crop species, sorghum-sudangrass, cowpea, and sunn hemp, were previously studied for their effects on fall armyworm populations, with sunn hemp showing high incompatibility with fall armyworm development. The cover crops were grown in 3 locations in north and north-central Florida and pitfall traps were used to compare numbers of carabid beetles caught in different cover crop treatments. Almost 2,000 predatory and omnivorous carabid beetles were collected. Three species in particular, Calosoma sayi Dejean, Tetracha carolina (L.), and Cicindela punctulata Olivier, are known predators of S. frugiperda in the laboratory and may aid in the reduction of populations in the field. There were no differences in beetle numbers among cover crop plants. In another trial, more beetles were collected in plots of a popular sunn hemp cultivar developed in the southeastern U.S., 'AU Golden', than in plots of another germplasm line, Tillage Sunn™. Further research should determine if the predatory species found in this study prey on S. frugiperda in the field and if this added mortality helps reduce crop damage. Muchas de las especies de escarabajos terrestres (Coleoptera: Carabidae) se alimentan de larvas y pupas de noctuidos. Por lo tanto, las prácticas agrícolas que mantienen o incluso mejoran las poblaciones de carábidos tienen el potencial de reducir las poblaciones de plagas noctuidas a través de la depredación. Una de esas plagas es el gusano cogollero, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), una plaga migratoria de cultivos en hileras, césped y hortalizas. Antes de migrar en primavera desde el sur de la Florida y el sur de Texas, se alimenta y se desarrolla con cultivos de cobertura como maíz y sorgo-pasto sudán con los cuales expande sus poblaciones. Aquí tomamos muestras de las especies y la densidad de las poblaciones de carábidos que estaban activos en cultivos de cobertura con diferentes capacidades para apoyar el desarrollo del gusano cogollero. Tres especies de cultivos de cobertura, sorgo-pasto sudán, caupí y cáñamo sunn, se estudiaron previamente por sus efectos sobre las poblaciones de gusano cogollero, y el cáñamo sunn mostró una alta incompatibilidad con el desarrollo del gusano cogollero. Se cultivaron los cultivos de cobertura en tres lugares del norte y centro-norte de la Florida y se utilizaron trampas de caída para comparar el número de escarabajos carábidos capturados en diferentes tratamientos de cultivos de cobertura. Se recolectaron casi 2.000 escarabajos carábidos depredadores y omnívoros. Tres especies en particular, Calosoma sayi Dejean, Tetracha carolina (L.) y Cicindela punctulata Olivier, son depredadores conocidos de S. frugiperda en el laboratorio y pueden ayudar a reducir las poblaciones en el campo. No hubo diferencias en el número de escarabajos entre las plantas de cultivos de cobertura. En otro ensayo, se recolectaron más escarabajos en parcelas del popular cultivar de cáñamo sunn desarrollado en el sureste de EE. UU., 'AU Golden', que en las parcelas de otra línea de germoplasma, Tillage Sunn™. Investigaciones adicionales deberían determinar si las especies depredadoras encontradas en este estudio se alimentan de S. frugiperda en el campo y si esta mortalidad adicional ayuda a reducir el daño a los cultivos. [ABSTRACT FROM AUTHOR]

Background and aims: Cover crops are an integral constituent of sustainable subtropical agroecosystems. Using grass/legume mixtures as opposed to monocultures has the potential to maximize their multifunctionality. This project aimed to understand temporal patterns of nitrogen (N) release of cover crop monocultures and mixtures in a subtropical vegetable production system. Methods: A litterbag experiment was established to study N release patterns of two commonly used grasses, two legumes, four two-species mixture each with one grass and one legume, and one four-species mixture. This field experiment was complemented by two laboratory incubations to quantify soil N mineralization after the termination of cover crops in 2020 and 2021. Results: The majority of residue N (> 60%) was lost in the first month of decomposition, suggesting no or minimal N release from cover crops beyond one cropping season. Mixtures enhanced N release relative to monocultures within the first two months; however, the timing of this synergistic effect depended on grass species in the mixture. Initial residue N concentration reasonably predicted the N loss trajectory of all residue types (r = -0.72; p < 0.05). Legumes showed the highest N mineralization rate, followed by mixtures and lastly grasses. Conclusions: Our findings reveal significant temporal variability in N release among different cover crop mixtures, despite the rapid decomposition across all cover crop treatments. Selection of appropriate species in cover crop mixtures helps to facilitate the synchronization of N release and crop update in subtropical systems where N management is extremely time sensitive. [ABSTRACT FROM AUTHOR]

Cover crops (CCs) have demonstrated their significance in enhancing the agronomic and economic performance of corn in succession. In this paper, we assess the agronomic responses and short-term economic returns of adopting cover crops (CCs) for corn cultivation in the sandy soils of the semiarid region of northeast Brazil, with the aim of addressing the additional challenges of CCs adoption in semiarid regions. The field study was conducted in Arapiraca, Alagoas, under no-tillage conditions for two cropping seasons. A randomized complete block design was employed, comprising six CCs (sunn hemp, spectabilis, jack bean, pigeon pea, lab lab, and millet) treatments and one fallow, with 18 replications. The CCs were cultivated for 60 days before corn planting. Drip irrigation was applied during the grain-filling stage of corn growth. Over the two cropping seasons, the biomass and nutrient cycling of the CCs, corn yield, and economic returns were determined, as well as the total organic carbon (TOC) and Mehlich-1 extractable P levels in the soil after corn harvest. The grain yields with sunn hemp, spectabilis, and jack bean were superior (~10%) to that of the fallow (7.7 vs. 7.1 Mg ha−1), irrespective of the cropping season. Sunn hemp exhibited a higher biomass accumulation and ensured greater nutrient cycling, except for K, while lab lab and millet displayed a similar potential, although substantial variations were observed between seasons. Under sunn hemp and jack bean, the TOC increased by ~9%, particularly in the second season. Regarding the available P, spectabilis and jack bean exhibited the highest levels, with an increase of ~74% compared to the fallow (~31.1 vs. 17.9 mg dm−3). Spectabilis and lab lab demonstrated more promising results, both agronomically and economically. However, millet and sunn hemp have the potential to reduce costs over multiple cropping seasons. Therefore, the adoption of cover crops is a sustainable and economically viable agricultural practice. However, it is essential to acknowledge that our results do not represent rainfed conditions and require further investigation. [ABSTRACT FROM AUTHOR]

Petroleum-based materials are often used in the packaging industry. However, the single use value of such products can be problematic with regard to proper waste disposal. As such, molded pulp packaging can be used as an alternative, given its ease of recycling, composting, and eventual biodegradation. In this work, we aims to study the pulp properties of sunn hemp and its usage as molded pulp products. For this purpose, unbleached beaten and unbeaten soda pulps derived from the whole stem of sunn hemp were examined for their fiber morphology, fibrillation, fiber classification, and physical properties. The sunn hemp pulp was subsequently molded using a batch molding machine. To determine the hydrophobicity of the molded pulp products, the molded samples were manufactured with and without additives. Finally, some properties of the molded pulp products were examined and compared with the commercially available bleached bagasse molded pulp products. It was observed that the molded products made from sunn hemp pulp with additives had a higher water contact angle than that of the commercial products. In terms of general usage, the molded products from sunn hemp pulp with additives were found to be capable of storing hot water, hot cooking oil, as well as microwaving water. We concluded that the sunn hemp pulp could be used as an alternative fibrous raw material in the production of molded pulp packaging.

Salt stress exerts adverse effects on yield by inhibiting or delaying seed germination and impeding seedling growth. Additionally, different salt concentrations have adverse effects on plant wet and dry weight and stem and shoot development. Crotalaria juncea L., the fastest-growing species within the Crotalaria genus, demonstrates a high degree of adaptability to both tropical and subtropical climates. To assess the tolerance of sunn hemp to salinity during the germination and early seedling stages, several indicators were determined at different (0, 50, 100, 150, 200, 250, and 300 mM) salt concentrations. Germination was conspicuously absent at salt concentrations of 250 mM and 300 mM. Notably, seedling characteristics, such as shoot length, root length, root fresh weight, seedling fresh weight, retention capability of the shoot, and the relative water content, experienced adverse effects with escalating salt concentrations. Intriguingly, the apex of seedling and root dry weights manifested at the pinnacle of salt concentration at 200 mM. Despite the discernible influence of heightened salt concentrations during the nascent seedling stage, the tolerance index was quantified at 100 mM, 150 mM, and 200 mM. Analyzing the study results through the lens of macro-minerals revealed an augmentation in Na and Cl content concomitant with increasing salt concentrations.

Abstract The rapid growth in the craft brewing industry is increasing the demand for winter barley production. Little recent research exists on producing winter barley for malting in the lower Midwestern United States, with a lack of understanding how previous legumes crops grown in rotation with winter barley interact with nitrogen (N) fertilization rates to affect grain yield and malting quality. To investigate these topics, a preliminary, 1‐year study was conducted in Missouri, USA, to test how growing soybean, a common rotational crop, and sunn hemp, a specialty forage crop, prior to winter barley, as well as two fall N fertilization rates (22.4 and 44.8 kg N ha−1), affected barley grain yield. Barley grain yield was unaffected by the previous legume crop choice or the fall N fertilization rate, suggesting that either crop provided adequate residual N to the succeeding barley crop. Additionally, malting quality was analyzed from representative grain samples to reveal adequate levels suitable for use in the craft brewing industry. This study's results reveal preliminary data supporting winter barley production in the lower Midwestern United States, with an indication that previously grown legume crops impact crop yield greater than fall N fertilizer rate.

This work evaluated the competence of two strains of cadmium (Cd)-resistant Streptomyces, namely Streptomyces rapamycinicus K5PN1, an indole-3-acetic acid (IAA) producer, and Streptomyces cyaneus 11-10SHTh, a siderophore producer on promoting Cd phytoextraction by sunn hemp. The results showed that S. rapamycinicus improved root elongation of sunn hemp seedlings under Cd stress conditions. S. rapamycinicus and S. cyaneus were colonized on the root surface of sunn hemp at concentrations of 2.3 × 104 and 6.4 × 103 CFU g−1 root fresh weight, respectively. The results of pot-culture experiments showed that S. rapamycinicus increased the root and shoot lengths, and dry biomass of sunn hemp planted in high Cd-contaminated soil. The Cd concentration in the leaves of sunn hemp inoculated with S. cyaneus (73.82 ± 2.20 mg kg−1 plant dry wt) was higher than that of plants with S. rapamycinicus inoculation and the uninoculated control. The phytoextraction of Cd by sunn hemp was significantly increased with Cd-resistant Streptomyces inoculation. In conclusion, both strains of Cd-resistant Streptomyces had potential on enhancing Cd phytoextraction efficiency of sunn hemp. Our study suggests the application of Cd-resistant Streptomyces can improve Cd phytoextraction by sunn hemp for restoration of Cd-polluted sites. Our study demonstrated the potential of two strains of Cd-resistant Streptomyces to stimulate Cd phytoextraction from soil by sunn hemp. Cadmium-resistant Streptomyces strongly stimulated Cd uptake and accumulation in sunn hemp planted in high level of Cd-polluted soil, supporting sunn hemp to be a superior Cd accumulator. [ABSTRACT FROM AUTHOR]

Petroleum-based materials are often used in the packaging industry. However, the single use value of such products can be problematic with regard to proper waste disposal. As such, molded pulp packaging can be used as an alternative, given its ease of recycling, composting, and eventual biodegradation. In this work, we aims to study the pulp properties of sunn hemp and its usage as molded pulp products. For this purpose, unbleached beaten and unbeaten soda pulps derived from the whole stem of sunn hemp were examined for their fiber morphology, fibrillation, fiber classification, and physical properties. The sunn hemp pulp was subsequently molded using a batch molding machine. To determine the hydrophobicity of the molded pulp products, the molded samples were manufactured with and without additives. Finally, some properties of the molded pulp products were examined and compared with the commercially available bleached bagasse molded pulp products. It was observed that the molded products made from sunn hemp pulp with additives had a higher water contact angle than that of the commercial products. In terms of general usage, the molded products from sunn hemp pulp with additives were found to be capable of storing hot water, hot cooking oil, as well as microwaving water. We concluded that the sunn hemp pulp could be used as an alternative fibrous raw material in the production of molded pulp packaging. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental 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 efficient use of green manure enhances sustainable nitrogen (N) cycling in agroecosystems. Appropriately utilizing the differences in N and fiber of green manure between cultivars or harvesting times strengthens the N use efficiency for subsequent crops. Therefore, it is necessary to clarify these differences. We clarified differences in nitrogen and fibers from four sunn hemp (Crotalaria juncea L.) commercial cultivars at two harvesting times after spring and summer seeding for three years. Only a few significant differences were found for any components between the four commercial cultivars. Although sunn hemp produced almost no flowers after the May seeding, the earliest flower opened at 50 days after seeding (DAS) and then significantly increased by 60 DAS (p < 0.05), after the July seeding. Sunn hemp DMY at 60 DAS had significantly larger values than those at 50 DAS all three years after the May and July seedings (p < 0.01). Significant differences between 50 DAS and 60 DAS were also observed for more than two years for the sunn hemp total carbon (TC), total nitrogen (TN), C/N ratio (CN), nitrate N (NO3-N), acid detergent fiber (ADF), and neutral detergent fiber (NDF) (p < 0.05). The sunn hemp N and ADF yields were significantly greater at 50 DAS than at 60 DAS in 2019 and 2020 (p < 0.05). These results suggest that the seeding and harvest time are important for decomposition estimations, although the differences between cultivars with equivalent flowering characteristics were not worth considering. Additionally, significant differences between years were found for all measurements except for NDF after the July seeding. This result suggests that the yearly effect of the difference in weather conditions, which causes differences in the yield, nitrogen, and ADF contents, is also an important factor for decomposition. [ABSTRACT FROM AUTHOR]

Simple Summary: The fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae), is considered a lepidopteran pest that originated from the Americas. In 2019, the fall armyworm (FAW) was first reported in Taiwan. Alternative host plants also play an important role in the insect population ecology. Hence, the study aimed to investigate how different alternative host plants, two grasses (napier and natal grass) and one legume (sunn hemp) crop, affect the population growth of this insect pest. The findings revealed that alternative host plants significantly affect the developmental period and reproduction of this pest. Based on the age-stage, two-sex life table, sunn hemp resulted to be a more suitable host plant while natal grass a less suitable host plant for FAW. Overall, all alternative host plants could support the growth and development of this pest in the absence of the main host plant. As a result, monitoring the host plants for the pest in the off-season could be used as a technique for prediction. After being discovered in Taiwan for the first time in June 2019, the polyphagous invasive fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera: Noctuidae), has since spread throughout the entire nation. In Taiwan, this insect has a significant impact on the quality and output of wheat, corn, sorghum, and millet. It may further infest more crops in Taiwan due to its diverse range of hosts and alternate hosts. Maize and other staple crops have already been the subject of several study. The biology of FAW has not yet been studied in relation to the alternative hosts, particularly those commonly found in Taiwanese farmlands. Therefore, this study proposed to investigate the effects of napier grass (Pennisetum purpureum), natal grass (Melinis repens), and sunn hemp (Crotalaria juncea) on the development, reproduction, survivorship, and population growth of FAW under laboratory conditions. According to the results, the developmental duration was considerably the shortest when FAW was reared on sunn hemp while the longest on natal grass. Furthermore, female adults reared on napier grass had a longer adult pre-oviposition period, total pre-oviposition period, oviposition period, longevity, highest fecundity, and highest net reproductive rate (Ro: 465.12). Among the tested three alternative host plants evaluated, sunn hemp had the highest intrinsic rate of increase (r: 0.1993), finite rate of increase (λ: 1.2206), and shortest mean generation time (T: 29.98). Therefore, this study suggests that all hosts plants can contribute to the development and outbreak of this pest in the absence of its primary host; however, sunn hemp was a relatively more suitable host plant for this insect. The possibilities for the FAW's growth and development vary depending on the host plant. Thereby, all potential host plants in the area should be extensively examined while developing an IPM program against FAW. [ABSTRACT FROM AUTHOR]

Sting nematode is acutely damaging to a wide range of crops and is relatively common in sandy soils in the southeastern United States. Sweetpotato is an important crop in this region, and its production may be expanding to localities where sting nematode is an important pest. Despite this, the relationship between sweetpotato and sting nematode is not well-defined. Therefore, the objectives of this study were to assess (1) the relative host status of sweetpotato for sting nematode and (2) damage potential of sting nematode on sweetpotato in repeated greenhouse experiments. A known sting nematode host (field corn), a known poor host (sunn hemp), and sweetpotato cultivars susceptible (‘Beauregard’) and resistant (‘Covington’) to southern root-knot nematode were challenged with sting nematode. In both trials, field corn supported greater final soil sting nematode abundances than sunn hemp or either sweetpotato cultivar. Based on the average reproductive factor, field corn was confirmed as a susceptible host, whereas sunn hemp and sweetpotato were poor hosts. Sting nematode did not impair the growth of any crop, suggesting greenhouse conditions were not conducive to damage since field corn sustains damage in field conditions. These results suggest that sunn hemp and sweetpotato could be useful rotation crops for managing sting nematode, but future work is needed to assess sting nematode pathogenicity on these crops under field conditions.

Lack of genomic resources in sunn hemp (Crotalaria juncea L.), a leguminous bast fiber crop, is one of the major constraints for germplasm characterization and genetic analysis. We identified non-redundant sets of a variety of molecular markers from the de novo flower-bud transcriptome of sunn hemp. These molecular markers included 1683 simple sequence repeats, 4759 intron length polymorphism markers primarily from protein-coding genes, and 3309 single nucleotide polymorphism allele-specific markers. All of these marker resources have been integrated into a simple database for easy access. To evaluate marker efficiency and polymorphism information content of the sampled primers, a subset of SSR and intron length polymorphism markers were validated in sunn hemp germplasm accessions to obtain average PIC values of 0.26–0.32. The SSR genotyping profiles also aided in the genetic distance matrix-based clustering of sunn hemp germplasm accessions. The ability of these molecular markers to successfully amplify in cross-genera bast fiber crops further demonstrated their effectiveness in genotyping. Thus, the current study describes the identification of previously undisclosed endogen)ous molecular markers in sunn hemp, which have potential applications in genetic studies and breeding in sunn hemp for bast fiber improvement. [ABSTRACT FROM AUTHOR]

Objetive. Determine the most appropriate substrate from mulberry biochar fertilizers for the germination and initial development of Crotalaria juncea L. Materials and methods. Six combinations were compared that were composed of: Treatment 1: 100% red ferralitic soil, Treatment 2: 50% soil and 50% biochar, Treatment 3: 50% soil and 50% compost, Treatment 4: 50% soil and 50% humus. worm, Treatment 5: 50% soil, 25% biochar, and 25% compost, and Treatment 6: 50% soil, 25% biochar, and 25% worm humus. Previously, biochar evaluations were carried out comparing its way of elaboration, and its origin of enrichment. Variables to measure: emergence (%), stem length (mm), stem thickness (mm), main root length (mm), leaves (number), and secondary roots (number). Results. The best results at 15 days were obtained with the substrate composed of 50% soil, 25% biochar, and 25% earthworm humus (treatment 6) with values of stem length (95.70 mm), stem diameter (1.10 mm), number of leaves (5.13), length of the main root (45.50 mm) and number of secondary roots (13.74) that give rise to a good development of the plant, favoring the best consistency of the root ball. Conclusions. It can be seen that the combined substrate of biochar, earthworm humus, and soil presents the potential for the development and germination of crotalaria in root ball. [ABSTRACT FROM AUTHOR]

The slow initial growth of hybrid brachiariagrass (Urochloa spp.) can require some months to achieve complete ground cover of a newly seeded area, leading to decreased forage production and increased weed infestation in the establishment year. To solve these problems, we attempted to sow seeds by mixing warm‐season annual forages with brachiariagrass at a brachiariagrass pasture establishment (University of Florida, USA, 2017 and 2018). Treatments were single seeding of 'Cayman' brachiariagrass solo (BR), sorghum sudangrass solo (Sorghum bicolor (L.) Moench; SD), and sunn hemp solo (Crotalaria juncea L.; SH) and two mixtures of these three forages at half (HSR) or full (FSR) of the recommended seeding rate. The seeding rates of FSR were, respectively, 10, 20, and 25 kg/ha for brachiariagrass, sudangrass, and sunn hemp. The treatments were distributed in a randomized complete block design with four replicates. Plots were harvested at 6, 12, 18, and 24 weeks after seeding. The number of brachiariagrass seedlings in the HSR and FSR treatments was less than half that in the BR (P <.05). The BR treatment had greater brachiariagrass herbage accumulation (HA) at all harvests than HSR (4%–75% of BR) or FSR (7%–66% of BR). This difference between the BR and mixture treatments became narrower in later harvests. In addition to the decreased number of brachiariagrass seedlings, light and nutrient competition between annual forages are considered to be the causes of lower brachiariagrass HA in the mixture treatments. Sunn hemp increased forage HA and crude protein concentrations at 6 weeks. Sudangrass provided overyielding forage until 18 weeks after seeding, with a similar nutritive value as brachiariagrass. Mixing warm‐season annual forages with brachiariagrass at the establishment, especially half of the seeding rates of sunn hemp and sudangrass, is a feasible management practice to increase HA during the first 12 weeks after seeding. [ABSTRACT FROM AUTHOR]

Lack of genomic resources in sunn hemp (Crotalaria juncea L.), a leguminous bast fiber crop, is one of the major constraints for germplasm characterization and genetic analysis. We identified non-redundant sets of a variety of molecular markers from the de novo flower-bud transcriptome of sunn hemp. These molecular markers included 1683 simple sequence repeats, 4759 intron length polymorphism markers primarily from protein-coding genes, and 3309 single nucleotide polymorphism allele-specific markers. All of these marker resources have been integrated into a simple database for easy access. To evaluate marker efficiency and polymorphism information content of the sampled primers, a subset of SSR and intron length polymorphism markers were validated in sunn hemp germplasm accessions to obtain average PIC values of 0.26–0.32. The SSR genotyping profiles also aided in the genetic distance matrix-based clustering of sunn hemp germplasm accessions. The ability of these molecular markers to successfully amplify in cross-genera bast fiber crops further demonstrated their effectiveness in genotyping. Thus, the current study describes the identification of previously undisclosed endogenous molecular markers in sunn hemp, which have potential applications in genetic studies and breeding in sunn hemp for bast fiber improvement.

Soil structural quality in areas under a no-tillage system is altered after successive crops, where compaction is a recurrent problem. The objective of this study was to evaluate the effect of different forms of soil decompaction on maize grain production. A randomized split-plot block design with four replications was used, in a 5 × 3 × 2 factorial arrangement, consisting of five forms of mechanical soil decompaction: ripping to a depth of 0.3 m, ripping to a depth of 0.5 m, subsoiling to a depth of 0.3 m, and subsoiling to a depth of 0.5 m, and no-tillage; three crop seasons: 2014/2015, 2015/2016, and 2016/2017; and two cover crops: sunn hemp and pearl millet. The soil resistance to root penetration (RP, 0.0–0.40 m), density (0.0–0.40 m), moisture (0.0–0.40 m), fresh (FB), and dry (DB) above-ground biomass of cover crops, and maize yield were evaluated. The subsoiling to a depth of 0.3 or 0.5 m results in higher production of sunn hemp biomass but has no effect on millet. Mechanical and biological soil decompaction improved maize grain yield throughout the seasons by at least 28% above the average yield in the study area region. The RP of up to 3.3 MPa did not negatively affect cover crop biomass production and maize grain. The association between the mechanical and biological decompaction method using cover crops provided greater resilience to the preparation carried out up to three years after the application of the treatments, resulting in greater corn grain productivity. [ABSTRACT FROM AUTHOR]

Abstract Background Fall armyworm, Spodoptera frugiperda (J. E. Smith) is a migratory moth that annually migrates northward each spring from sites in southern Florida and southern Texas. This caterpillar pest feeds on and damages row, turf and vegetable crops in the eastern and central U.S. Before migrating in spring, it feeds on cover crops in central and eastern Florida and expands its populations. Our objective was to use multi-year studies to compare fall armyworm populations that develop in cover crop plants. Methods A series of field experiments and a laboratory feeding study were conducted to compare infestation and feeding and of fall armyworm on different cover crop plants. Field experiments had plots planted with corn (Zea mays L.), sorghum-sudangrass [Sorghum bicolor (L.) Moench], a standard cover crop in Florida, and two alternative cover crops, sunn hemp (Crotalaria juncea L.) and cowpea [Vigna unguiculata (L.) Walpers spp. unguiculata]. Another trial compared populations in sorghum-sudangrass and in mixtures of sorghum-sudangrass with buckwheat (Fagopyrum esculentum Moench) or pearl millet (Cenchrus americanus (L.) Morrone). Fall armyworm larvae were fed and allowed to develop on different sunn hemp germplasm in a laboratory trial. Results Field populations of fall armyworm were highest on corn, followed by sorghum-sudangrass. Sunn hemp and cowpea had larval populations 70–96% less than on sorghum-sudangrass, suggesting replacement of this cover crop with either plant species might help reduce areawide populations of resident or migratory fall armyworm. Larvae collected from cover crop plots had parasitism levels that averaged 30%, with Chelonus insularis (Hymenoptera: Braconidae) emerging as the most commonly-collected species. Larval feeding on different sunn hemp germplasm lines resulted in no difference in weight gain. Conclusions Replacing sorghum-sudangrass with sunn hemp varieties or germplasm should be acceptable as a replacement cover crop for areawide management of fall armyworm.

There is growing interest in malting barley (Hordeum vulgare L.) production in the Northeastern United States. This crop must meet high quality standards for malting but can command a high price if these quality thresholds are met. A two-year field experiment was conducted from 2015 to 2017 to evaluate the impact of two leguminous cover crops, sunn hemp (Crotalaria juncea L.) and crimson clover (Trifolium incarnatum L.), on subsequent winter malting barley production. Four cover crop treatments—sunn hemp (SH), crimson clover (CC), sunn hemp and crimson clover mixture (SH + CC), and no cover crop (NC)—were grown before planting barley at three seeding rates (300, 350, and 400 seeds m−2). SH and SH + CC produced significantly more biomass and residual nitrogen than the CC and NC treatments. Higher barley seeding rates led to higher seedling density and winter survival. However, the subsequent spring and summer barley growth metrics, yield, and malting quality were not different in any of the treatments. There is much left to investigate in determining the best malting barley production practices in the Northeastern United States, but these results show that winter malting barley can be successfully integrated into crop rotations with leguminous plants without negative impacts on barley growth, yield, and grain quality.

This research was conducted to determine some silage quality traits of silage alternatives prepared in different mixture rates of sorghumsudangrass hybrid [Sorghum bicolor (L.) Moench x Sorghum sudanense (Piper) Stapf] which is more drought tolerant than maize, and sunn hemp (Crotalaria juncea L.) which has a high protein content, under Mediterranean ecological conditions. Different silage alternatives (sorghum-sudangrass hybrid % - sunn hemp %; 100-0, 80-20, 60-40, 50-50, 40-60, 20-80, 0-100, based on fresh matter) were prepared in a randomized design with four replications in both years. Silage weight loss and pH, dry matter, Flieg score, crude protein, crude ash, ADF, NDF, metabolizable energy, dry matter intake, digestible dry matter and relative feed value were determined at the end of 8 weeks ensilage. According to results, good quality silages can be made from all silage alternatives of sorghum-sudangrass hybrid and sunn hemp without affecting the fermentation process. In addition, silages made by adding sunn hemp to sorghum-sudangrass hybrid at different rates have more nutritional value than pure sorghum-sudangrass hybrid silage without sacrificing quality. Ensiling the sorghum-sudangrass hybrid on a fresh matter basis with up to 50% sunn hemp can be recommended for optimum quality. In animal nutrition, it would be best to choose one of the silage alternatives according to the need in the rations. [ABSTRACT FROM AUTHOR]

Many factors cause increasing Pb contamination in soils, including intensive crop production, motor vehicle exhaust gas around agricultural land areas, or irrigation mixed with household. An effort is needed to minimize Pb contamination in soils. This experiment aimed to examine the potential of Crotalaria juncea L. intercropped for minimizing the accumulation of Pb in vegetable crops grown using agrochemicals. The treatments tested were monoculture of Brassica rapa, monoculture of Phaseolus vulgaris, monoculture of C. juncea, intercropping C. juncea with B.rapa, and intercropping C. juncea with P. vulgaris. Results of the study showed that planting of C. juncea reduced the total dry weight of B. rapa by 33.47% and increased the total dry weight of P. vulgaris by 17.41% compared to monoculture. Intercropping of B rapa or P. vulgaris with C. juncea reduced the total Pb concentration of B. rapa by 45.64% and that of P. vulgaris by 16.22%. Planting of C. juncea reduced the Pb concentration in B. rapa by 21.23% (Pb 0.89 mg kg-1) and that in P. vulgaris by 76.03% (Pb 0.93 mg kg-1). Monoculture planting of C. juncea and intercropping of C. juncea with B. rapa or P. vulgaris reduced the concentration of available Pb and total Pb in the soil to not detected value, compared to monoculture planting of B. rapa and P. vulgaris. [ABSTRACT FROM AUTHOR]

Background & Objective: Use of cover crops for controlling weeds is an environmental friendly alternative to conventional chemical and mechanical methods. Kohlrabi is a cool-season hardy crop which can be grown in early spring. The crop is well known in Europe and other regions as a health staple in human’s diets. The aim of the present study was to investigate the effectiveness of using sunn hemp and rye cover crops as monoculture or mixed in controlling weeds and improving yield of kohlrabi. Materials & Method: A two-year field study was conducted. Experimental treatments consisted of monoculture rye (Secale cereal L.), sunn hemp (Crotalaria juncea) and their mixture and no cover crop as control. Results: Cover crops biomass were 379.7 and 473.9 g.m-2 in first and second growing seasons, respectively. Averaged over two years, weed dry weight reduced by 52.6, 42.5 and 45.4 percentage in rye monoculture, sunn hemp monoculture, and mixed cover crops, respectively. Monoculture rye was more effective in suppressing the dominant weeds. Rye reduced lambsquarter, pigweed, and wild mustard by about 44, 60, and 52 percentage, respectively. On average, use of cover crops improved kohlrabi yield by 30%. Sunn hemp followed by mixed cover crops were more effective in kohlrabi yield improvement. Conclusion: Cover crops provide many ecological benefits. When weed suppression is the main goal of cover cropping, rye with fast growing habit and extensive root system is more efficient. However, legumes or mixture of legumes and grass are more effective in crop yield improvement.

The relay-cropping (R) of a winter cereal and a high biomass yielding legume for advanced biofuel production can enlarge the legume growing season, thus increase its biomass yield and synchronize nitrogen (N 2)-fixation capacity to uptake. The aim of the present study was to evaluate the biomass and food yield of two sunn hemp (Crotalaria juncea L.; cv. Ecofix) – wheat (Triticum aestivum L.; cv. Bologna) relay-cropping systems compared to double-cropping, in order to explore the impact on grain and biomass yield of the variable crops overlapping periods. The evaluated relay-cropping systems foreseen an early November wheat sowing into no till bare soil with: i) sunn hemp harvested at full flowering (beginning of November, R1) and ii) sunn hemp harvested at the end of flowering (end of November, R2). In the control (C) double-cropping, sunn hemp was harvested at the beginning of flowering (end of September). Quantitative and qualitative parameters were evaluated for each system across two growing seasons (2019–20 and 2021–22). Sunn hemp biomass and wheat straw residues were determined. The grain qualitative parameters determined for wheat were: grain volume weight (VW), crude protein, wet gluten, starch and Zeleny index (ZI). The R1 and R2 sunn hemp-wheat relay-cropping biomass yield (12.5 Mg d.m. ha−1 y−1) was similar to C (11.3 Mg d.m. ha−1 y−1). In 2019–20, environmental conditions were more favorable, thus, yields were higher than in 2021–22 by 72 %. Wheat grain yields in 2021–22 were higher in R1 (2.9 Mg d.m. ha−1) than C (2.0 Mg d.m. ha−1), with R2 showing intermediate values. In 2019–20, however, the grain quality was higher in R1 than in C for crude protein (+11 %), wet gluten (+15 %), and ZI (+26 %) eventually due to an increased N 2 -fixation by sunn hemp that reached full flowering. The local availability of low iLUC risk lignocellulosic feedstock for advanced biofuel could be increased through crop intensification with relay-cropping, showing the potential to provide additional biomass and enhance food quality thus complying with the additionality measures set out by the Delegated Regulation of REDIII. • Relay-cropping increases the availability of lignocellulosic feedstock for biofuels • Relay-cropping stretch the sunn hemp' growing season, leading to higher biomass yield • Relay-cropping improve the grain quality and the sustainability of the farming system [ABSTRACT FROM AUTHOR]

After being discovered in Taiwan for the first time in June 2019, the polyphagous invasive fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera: Noctuidae), has since spread throughout the entire nation. In Taiwan, this insect has a significant impact on the quality and output of wheat, corn, sorghum, and millet. It may further infest more crops in Taiwan due to its diverse range of hosts and alternate hosts. Maize and other staple crops have already been the subject of several study. The biology of FAW has not yet been studied in relation to the alternative hosts, particularly those commonly found in Taiwanese farmlands. Therefore, this study proposed to investigate the effects of napier grass (Pennisetum purpureum), natal grass (Melinis repens), and sunn hemp (Crotalaria juncea) on the development, reproduction, survivorship, and population growth of FAW under laboratory conditions. According to the results, the developmental duration was considerably the shortest when FAW was reared on sunn hemp while the longest on natal grass. Furthermore, female adults reared on napier grass had a longer adult pre-oviposition period, total pre-oviposition period, oviposition period, longevity, highest fecundity, and highest net reproductive rate (Ro: 465.12). Among the tested three alternative host plants evaluated, sunn hemp had the highest intrinsic rate of increase (r: 0.1993), finite rate of increase (λ: 1.2206), and shortest mean generation time (T: 29.98). Therefore, this study suggests that all hosts plants can contribute to the development and outbreak of this pest in the absence of its primary host; however, sunn hemp was a relatively more suitable host plant for this insect. The possibilities for the FAW’s growth and development vary depending on the host plant. Thereby, all potential host plants in the area should be extensively examined while developing an IPM program against FAW.

Summary: Cover crops can be a useful tool for managing plant-parasitic nematodes provided they are poor or non-hosts for the target nematode species. A glasshouse experiment was done to determine the host status of four common cover crops in Florida, sunn hemp, cowpea, sorghum sudangrass and sunflower, to pure populations of four common tropical root-knot nematode (RKN) species Meloidogyne javanica (Mj), M. incognita (Mi), M. enterolobii (Me) and M. arenaria (Ma). Tomato was included as a susceptible control. Eight weeks after nematode inoculation (WAI), tomato showed the highest root gall damage for all tested RKN species, with gall indices (GI) between 7 (Ma) and 8.5 (Me) and reproduction factor (RF) ranging from 20 (Ma) to 50 (Mj). No visible root galls were observed for any of the RKN species on sunn hemp and sorghum sudangrass at 8 WAI. However, Mj and Mi were able to reproduce slightly on sorghum sudangrass (RF = 0.02 and 0.79, respectively). Sunflower and cowpea were infected by all four tested RKN species, but host suitability varied. Sunflower root galling ranged from 1.1 (Me) to 4.5 (Mj) and RF = 3.2 (Me) to 28.7 (Mj), while cowpea root galling ranged from 0.6 (Mi) to 5.1 (Me) and RF = 0.8 (Mi) to 67.3 (Mj). Sunn hemp and, to a lesser extent, sorghum sudangrass were poor hosts to all four tested RKN species. Sunflower was a good host to all RKN species, but root gall damage and RF were lowest for Me. Cowpea was a good host to Mj , Me and Ma , but a poor host to Mi. Our results confirm and stress the importance of RKN species identification when selecting cover crops as an RKN management strategy. [ABSTRACT FROM AUTHOR]

Abstract Crotalaria (Fabaceae) occurs abundantly in tropical and subtropical regions and has about 600 known species. These plants are widely used in agriculture, mainly as cover plants and green manures, in addition to their use in the management of phytonematodes. A striking feature of these species is the production of pyrrolizidine alkaloids (PAs), secondary allelochemicals involved in plant defense against herbivores. In Crotalaria species, monocrotaline is the predominant PA, which has many biological activities reported, including cytotoxicity, tumorigenicity, hepatotoxicity and neurotoxicity, with a wide range of ecological interactions. Thus, studies have sought to elucidate the effects of this compound to promote an increase in flora and fauna (mainly insects and nematodes) associated with agroecosystems, favoring the natural biological control. This review summarizes information about the monocrotaline, showing such effects in these environments, both above and below ground, and their potential use in pest management programs.

There is growing interest in malting barley (Hordeum vulgare L.) production in the Northeastern United States. This crop must meet high quality standards for malting but can command a high price if these quality thresholds are met. A two-year field experiment was conducted from 2015 to 2017 to evaluate the impact of two leguminous cover crops, sunn hemp (Crotalaria juncea L.) and crimson clover (Trifolium incarnatum L.), on subsequent winter malting barley production. Four cover crop treatments—sunn hemp (SH), crimson clover (CC), sunn hemp and crimson clover mixture (SH + CC), and no cover crop (NC)—were grown before planting barley at three seeding rates (300, 350, and 400 seeds m−2). SH and SH + CC produced significantly more biomass and residual nitrogen than the CC and NC treatments. Higher barley seeding rates led to higher seedling density and winter survival. However, the subsequent spring and summer barley growth metrics, yield, and malting quality were not different in any of the treatments. There is much left to investigate in determining the best malting barley production practices in the Northeastern United States, but these results show that winter malting barley can be successfully integrated into crop rotations with leguminous plants without negative impacts on barley growth, yield, and grain quality. [ABSTRACT FROM AUTHOR]

Sunn hemp (Crotalaria juncea) has been widely used as cover crop in the USA and due to superior biomass accumulation and nutritive value, there is interest from producers to use sunn hemp as forage for livestock. However, sunn hemp has pyrrolizidine alkaloids, which can affect animal performance. The objective of this study was to evaluate the effects of feeding sunn hemp hay to early-weaned beef calves in a dry lot in Florida. The experiment was conducted at the UF/IFAS Range Cattle Research and Education Center, Ona, FL from April to May 2021 (42 d). Treatments were calves receiving sunn hemp or stargrass (Cynodon nlemfuensis) hay distributed in a randomized complete block design with 12 replicates. Calves were supplemented with concentrate at 1.3% BW daily (18% CP and 78% TDN). Twenty-four Angus crossbred calves were weaned with 90 ± 14 kg BW and grazed annual ryegrass (Lolium multiflorum) with 1% BW concentrate supplementation for approximately 60 d. Subsequently, calves were randomly distributed and assigned to experimental units (pen) on 14 April 2021 with initial BW of 184 ± 10 kg. 'Ubon' sunn hemp hay was harvested approximately 49 d after seeding when 75% of the plants were initially flowering. Ground hay was fed daily targeting 10% refusals, and the initial CP and in vitro digestible organic matter concentrations of sunn hemp and stargrass hay were 9 and 48%, and 9 and 47%, respectively. The average concentration of pyrrolizidine alkaloids from sunn hemp hay was 58 μg/g DM. Early-weaned calves receiving stargrass had a tendency to have greater ADG than sunn hemp (0.5 vs. 0.4 kg/d, P = 0.09), and had greater forage DM intake (1.2 vs. 1.0% BW, P < 0.01) and total DM intake (2.5 vs. 2.3% BW, P < 0.01). Conversely, diets with sunn hemp had greater in vivo DM digestibility than stargrass (68 vs. 62%, P = 0.04). There was no difference between treatments on parasite egg count (mean = 45 eggs/3 g feces, P = 0.25) and coccidia egg count (log10 eggs/g feces, P = 0.35). Earlyweaned calves receiving sunn hemp consumed 0.25 g pyrrolizidine alkaloids/d; however, there was no detectable amount (< 0.05 μg/g DM) of pyrrolizidine alkaloids in the feces. The presence of pyrrolizidine alkaloids in sunn hemp may be the potential cause of decreased early-weaned calves forage intake and animal performance. [ABSTRACT FROM AUTHOR]

Summary: Field studies were conducted in Mato Grosso, Brazil and Georgia, USA to evaluate the efficacy of Crotalaria spp. as a rotational cover crop for managing Meloidogyne incognita in cotton (Gossypium hirsutum). The two studies differed in how Crotalaria spp. were incorporated into the cotton production system to reflect differences in climate (tropical vs subtropical) and production systems typical for the two regions. In Mato Grosso, Crotalaria juncea and C. spectabilis were planted after soybean in late summer, grown for approximately 300 days, and incorporated into the soil 6-15 days prior to cotton planting. In Georgia, C. juncea and a nematode-resistant cowpea, Vigna ungiculata , were planted after maize in the late summer, grown until killed by frost in the early winter, and cotton was planted in the next season. Soil population densities of M. incognita and root galling in cotton were similar in cotton following either fallow, resistant cowpea, or Crotalaria spp. However, Crotalaria spp. significantly increased cotton plant height at the time of harvest relative to the other treatments. Except for one of the experiments in Brazil, incorporation of Crotalaria spp. in the rotational scheme did not increase cotton yield. Results indicate that a cover crop of Crotalaria spp. does not suppress M. incognita in cotton production system more than a fallow period or planting a resistant cover crop. [ABSTRACT FROM AUTHOR]

The utilisation of plant allelopathy is an important tool in a diversified weed management strategy. Allelochemicals are released by some plants, such as sunn hemp (Crotalaria juncea L.), to inhibit the growth of neighbouring plants. This species was tested for use as an allelopathic plant for weed control in cropping systems. The allelopathic properties of sunn hemp were tested under field conditions at different timings of 4, 8, 12 and 16 weeks after planting (WAP). The results showed that sunn hemp at 8, 12 and 16 WAP significantly decreased the total number of weeds compared with the control weedy check. The similar trend of decreasing weed number was observed in grass and broadleaf weeds, as well as sedge. The allelopathic activity of sunn hemp was further investigated in the soil planted with sunn hemp and water extracts on tested plants. Phytotoxicity of the soil, planted with sunn hemp at different timings, did not significantly decrease germination, shoot length, root length and dry weight of tested plants. However, the water extracts caused significantly decreased germination and plant growth, especially the shoot extracts exhibited the inhibitory effects more than the root extracts. Interestingly, the extracts from sunn hemp at 4 WAP had higher inhibitory effects than the extracts from other stages. These results suggest that sunn hemp growth stage is an important consideration for maximising biological weed control in cropping systems. [ABSTRACT FROM AUTHOR]

Soil structural quality in areas under a no-tillage system is altered after successive crops, where compaction is a recurrent problem. The objective of this study was to evaluate the effect of different forms of soil decompaction on maize grain production. A randomized split-plot block design with four replications was used, in a 5 × 3 × 2 factorial arrangement, consisting of five forms of mechanical soil decompaction: ripping to a depth of 0.3 m, ripping to a depth of 0.5 m, subsoiling to a depth of 0.3 m, and subsoiling to a depth of 0.5 m, and no-tillage; three crop seasons: 2014/2015, 2015/2016, and 2016/2017; and two cover crops: sunn hemp and pearl millet. The soil resistance to root penetration (RP, 0.0–0.40 m), density (0.0–0.40 m), moisture (0.0–0.40 m), fresh (FB), and dry (DB) above-ground biomass of cover crops, and maize yield were evaluated. The subsoiling to a depth of 0.3 or 0.5 m results in higher production of sunn hemp biomass but has no effect on millet. Mechanical and biological soil decompaction improved maize grain yield throughout the seasons by at least 28% above the average yield in the study area region. The RP of up to 3.3 MPa did not negatively affect cover crop biomass production and maize grain. The association between the mechanical and biological decompaction method using cover crops provided greater resilience to the preparation carried out up to three years after the application of the treatments, resulting in greater corn grain productivity.

This study was performed to investigate the ability of Streptomyces sp. St1 that has indole-3-acetic acid (IAA) production and phosphate solubilizing ability on the growth and remediation efficiency of sunn hemp cultivated in 202.9 mg/kg of anthracene-contaminated soils. Streptomyces sp. St1 immobilized in rice straw and coconut husk could increase sun hemp growth. On day 36 of the experiment, shoot length, shoot fresh weight, shoot dry weight, root fresh weight and total chlorophyll content in sunn hemp leaves were around 41.2-44.4 cm, 2.81-3.45 g, 0.44-0.53 g, 0.46-0.55 g and 47.4-79.2 mg/ml, respectively, in soil amended with Streptomyces sp. St1 immobilized in rice straw and coconut husk. Sunn hemp cultivated in anthracene-spiked soil without Streptomyces sp. St1 inoculation died at 36 d after germination. Additional immobilized cells+spores of Streptomyces sp. St1 in rice straw and coconut husk in soil planted with sunn hemp maintained the cell density to a better extent than the free cells+spores. However, both free and immobilized cells+spores of Streptomyces sp. St1 did not improve anthracene removal from the soil with or without sunn hemp planting. [ABSTRACT FROM AUTHOR]

This study investigates enhancing the biogas production of sunnhemp by pretreatment, before the anaerobic digestion and co-digestion processes, to address the complex and recalcitrant structure of the plant. Fresh sunnhemp harvested at a cutting interval of 50 days is used in the study. Five systems (each with a 5 litre useable volume) are operated semi-continuously with five different ratios of the feedstock by feeding separate feedstocks every five days with a hydraulic retention time (HRT) of 40 days. The system operates at room temperature (30 °C). The study uses sunnhemp as 20% of the feedstock and also considers sunnhemp mixed with cow manure at different ratios, with the weighed sunnhemp being pretreated with dilute sodium hydroxide. Pretreatment of sunnhemp before digestion produces a methane (CH 4) yield 89% greater than that of the untreated sunnhemp. It requires 3.597 kg of dry sunnhemp to produce 1 m3 of CH 4 and the annual CH 4 yield per hectare is 19,015 m3. In the pretreatment of sunnhemp before co-digestion, the increased CH 4 yield depends on the amount of pretreated sunnhemp in the feedstocks. However, the %CH 4 , the CH 4 production level and the system stability depend on the optimal ratio of the sunnhemp to cow manure. The initially prepared sunnhemp to cow manure ratio is recommended at 10 g:10 g in 80 mL of water. At this ratio, the %CH 4 and the CH 4 yield are 53.84% and 313 kg chemical oxygen demand (COD) removed, respectively, and the COD removal efficiency is 56.4%. Sunnhemp has high potential and it is worth pretreating before producing biogas. Using sunnhemp to produce biogas is recommended to decrease greenhouse gas emissions and mitigate global warming. • A promising way to increase biogas from sunnhemp is to pretreat it with NaOH. • The CH 4 yield obtained is 89% greater than from the untreated sunnhemp. • To produce 1 m3 of CH 4 requires 3.597 kg sunnhemp when pretreated. • The appropriate initially prepared sunnhemp:cow manure is 10g:10g in 80 mL of water. • Pretreated sunnhemp has high potential for biogas production. [ABSTRACT FROM AUTHOR]