Potential of Mauritius Hemp (Furcraea gigantea Vent.) for the Remediation of Chromium Contaminated Soils

The present study was conducted to evaluate the ability of a high biomass producing, drought tolerant succulent plant Mauritius hemp (Furcraea gigantea Vent.) for its tolerance to different levels of Cr (0, 25, 50, 100 and 200 mg Cr kg soil^?1) and its potential for phytoremediation purposes. Based on the data on inhibition of the growth of plants with Cr, tolerance index and grade of growth inhibition, it was observed that the plant could tolerate up to 50 mg Cr kg ^?1 soil. Absorption of Cr from soil to plant and its translocation into plant tissues were discussed in terms of bio concentration factor (BCF), transfer factor (TF), and translocation efficiency (TE%). Cr was mainly accumulated in the roots and exclusion of Cr was found to be the principal physiological tolerance mechanism followed by a marked increase in proline, ascorbic acid, total free amino acids in the leaf tissue and malic acid in the rhizosphere samples to counter Cr stress. Based on the tissue concentration of Cr (< 300 μg g^?1 in the leaves and TF<1), it was concluded that, Furcraea gigantea could not be considered a hyperaccumulator and therefore unsuitable for phytoextraction of Cr. Nevertheless, Furcraea gigantea could be a suitable candidate for phytostablization of Cr contaminated soils.     

Hemp sesbania (Sesbania exaltata) control in rice (Oryza sativa) with the bioherbicidal fungus Colletotrichum gloeosporioides f. sp. aeschynomene formulated in an invert emulsion

In greenhouse and field experiments, an invert emulsion (MSG 8.25) was tested with dried, formulated spores of the bioherbicidal fungus Colletotrichum gloeosporioides f. sp. aeschynomene, a highly virulent pathogen of the leguminous weed Aeschynomene virginica (northern jointvetch), but considered ‘immune’ against another more serious leguminous weed, Sesbania exaltata (hemp sesbania). A 1:1 (v/v) fungus/invert emulsion mixture resulted in 100% infection and mortality of inoculated hemp sesbania seedlings over a 21-day period under greenhouse conditions. In replicated field tests of the fungus/invert formulation conducted in Stuttgart, AR, and Stoneville, MS, hemp sesbania was controlled 85 and 90%, respectively. These results suggest that this invert emulsion expands the host range of C. gloeosporioides f. sp. aeschynomene, with a concomitant improvement of the bioherbicidal potential of this pathogen.     

Evaluating the Potential for Harmonized Prediction and Comparison of Disposal‐Stage Greenhouse Gas Emissions for Biomaterial Products

The carbon footprint (CF) of biofuels and biomaterials is a barrier to their acceptance, yet the greenhouse gas emissions associated with disposing of biomaterials are frequently omitted from analyses. This article investigates whether harmonization is appropriate for calculating the importance of biomaterials’ disposal. This research shows that disposal stages could double a biomaterial's CF, or reduce it to the point that it could claim to be zero carbon. Incineration with combined heat and power coupled with on‐site energy production in the biorefinery are identified as prerequisites to being zero carbon. The article assesses the current UK waste infrastructure's ability to support a low‐carbon bio‐based future economy, and finds that presently it only achieves marginal net reductions when compared to landfill and so cannot be said to support low‐carbon biomaterials, though the article challenges the polluter pays principle where low‐carbon disposal infrastructure are not available. Reuse and recycling are shown to have the potential to offset all the emissions caused by landfill of biomaterials. However, the savings are not so great as to offset the biomaterial's upstream emissions. The study explores the ability to overcome the barriers to incorporating disposal into life cycle assessment while identifying limitations of using harmonization as an assessment method. Specifically, data availability and industry consensus are flagged as major barriers. The study also uses sensitivity analysis to investigate the influence of methodological choices, such as allowing additional reuse and recycling stages, classifying biomaterials into different types, and choosing between opposing allocation methods.     

Twin-screw extrusion of ‘Pesta’-encapsulated biocontrol agents

World Journal of Microbiology and Biotechnology -     

大麻沤麻液细菌种群多样性

从分子水平分析大麻沤麻液中细菌种类及其优势菌群,为筛选出大麻微生物脱胶的生产菌种奠定基础。采用PCR-DGGE技术研究大麻沤麻液中细菌种群的多样性及动态变化,使用Gel-Pro Analyzer 4.5软件分析DGGE指纹图谱,并对优势条带进行分析。结果表明:从发酵初期过渡到主发酵期细菌种群多样性上升,群落演替迅速,从主发酵期进入到发酵末期,细菌种群多样性下降,群落演替缓慢;在整个发酵过程中,细菌种群多样性指数在发酵中期(72h)达到高峰,说明发酵中期细菌种群数量、优势菌群种类达到了最高值,发酵初期和末期以不可培养细菌为主,主发酵期以成团泛菌属为主。     

Effects of selected pectinolytic bacterial strains on water-retting of hemp and fibre properties

Aims:  To study the effect of selected bacterial strains on hemp water-retting and properties of retted fibre.
Methods and Results:  The trials were performed in laboratory tanks. The traditional water-retting process, without inoculum addition, was compared to a process modified by inoculating water tanks with two selected pectinolytic bacteria: the anaerobic strain Clostridium sp. L1/6 and the aerobic strain Bacillus sp. ROO40B. Six different incubation times were compared. Half the fibre obtained from each tank was combed. Micromorphological analyses were performed by scanning electron microscopy on uncombed and combed fibres. Moreover, organoleptic and chemical analyses of uncombed fibres were performed.
Conclusions:  The inoculum , besides speeding up the process, significantly improved the fibre quality. The fibre was not damaged by mechanical hackling, thanks to the good retting level obtained by the addition of selected strains, differently to what happened with the traditionally retted fibre. The best fibre quality was obtained after 3–4 days of retting with the addition of the bacterial inoculum .
Significance and Impact of the Study:  Retting is the major limitation to an efficient production of high-quality hemp fibres. The water-retting process and fibre quality were substantially improved by simultaneously inoculating water tanks with two selected pectinolytic strains.     

Isolation of microsatellite markers in Cannabis sativa L. (marijuana)

We have identified 15 variable microsatellite loci in Cannabis sativa. In 48 samples from five fibre crop seed accessions, we detected an average of 10 alleles per locus (range 2–28) with mean heterozygosity of 0.68 (range 0.28–0.94). Significant genetic differentiation was found between accessions (F_ST = 0.12, P < 0.001). These markers have utility for characterizing genetic diversity in cultivated and naturalized Cannabis populations.     

Effect of Crotalaria juncea Amendment on Nematode Communities in Soil with Different Agricultural Histories

Effect of sunn hemp (Crotalaria juncea) hay amendment on nematode community structure in the soil surrounding roots of yellow squash (Cucurbita pepo) infected with root-knot nematodes was examined in two greenhouse experiments. Soils were from field plots treated long-term (LT) with yard-waste compost or no yard-waste compost in LT experiment, and from a short-term (ST) agricultural site in ST experiment. Soils collected were either amended or not amended with C. juncea hay. Nematode communities were examined 2 months after squash was inoculated with Meloidogyne incognita. Amendment increased (P < 0.05) omnivorous nematodes in both experiments but increased only bacterivorous nematodes in ST experiment (P < 0.05), where the soil had relatively low organic matter (<2%). This effect of C. juncea amendment did not occur in LT experiment, in which bacterivores were already abundant. Fungivorous nematodes were not increased by C. juncea amendment in either experiment, but predatory nematodes were increased when present. Although most nematode faunal indices, including enrichment index, structure index, and channel index, were not affected by C. juncea amendment, structure index values were affected by previous soil organic matter content. Results illustrate the importance of considering soil history (organic matter, nutrient level, free-living nematode number) in anticipating changes following amendment with C. juncea hay.     

Management of Rotylenchulus reniformis in Pineapple,Ananas comosus,by Intercycle Cover Crops

The effects of intercycle cover crops on Rotylenchulus reniformis population densities in pineapple were evaluated in one greenhouse and two field experiments. In the greenhouse, Crotalaria juncea, Brassica napus, and Tagetes erecta were planted for 3 months and then incorporated. These treatments were compared to weedy fallow with or without 1,3-dichloropropene (1,3-D) in three soils (Makawao fallow, Wahiawa fallow, and Wahiawa pineapple) naturally infested with R. reniformis. All cover crop incorporation suppressed R. reniformis numbers in cowpea more than did the weedy treatment in the Makawao (P < 0.05) but not in the Wahiawa soils. Crotalaria juncea treatment increased bacterivorous nematodes and nematode-trapping fungal population densities more than the other treatments in Makawao fallow and Wahiawa pineapple-planted soils. The field trials included the same plants as well as Sinapis alba. Treatments with Crotalaria juncea and 1,3-D maintained lower R. reniformis population densities on pineapple longer than other cover crops or weedy fallow treatments. Crotalaria juncea could have suppressed R. reniformis because it is a poor host and because it enhances nematode-trapping fungi when incorporated into soil. Treatment with 1,3-D reduced microbial activities but produced the greatest pineapple yield.     

麻类织物对须癣毛癣菌生长抑制作用的研究

目的通过分析汉麻、亚麻和苎麻对须癣毛癣菌生长的影响,探讨麻类织物对浅部真菌的抑制作用。方法实验采用振荡法。将3种麻类织物分别与须癣毛癣菌混合培养,对照组为棉布组,3d后分别取培养液稀释5倍后涂布培养皿,计算各自的菌落数和抑菌率并进行统计分析。结果麻类织物组菌落数明显少于对照组棉布组(P<0.01),3种麻类织物对须癣毛癣菌的抑菌率均高于60%,但3种麻类织物的抑菌率之间无明显差异(P<0.01)。结论3种麻类织物均可显著抑制须癣毛癣菌的生长,麻类织物有可能用来预防由须癣毛癣菌引起的足癣、股癣等浅部真菌病。