Effect of Extraction Variables on the Biodegradable Chelant-Assisted Removal of Toxic Metals from Artificially Contaminated European Reference Soils

Development of aminopolycarboxylate chelants (APCs) having enhanced biodegradability is gaining increasing focus to replace the EDTA and its homologs with those used widely for the ex situ treatment of contaminated soils and are potential eco-threats. The paper reports the chelant-assisted extraction of the toxic metals (Cd, Cu, Pb, and Zn) from the metal-spiked European reference soils (Eurosoil 1 and Eurosoil 4) using biodegradable APCs, namely EDDS, GLDA, and HIDS. The effects of chelant-to-metal molar ratio, solution pH, and metal/chelant stability constants were evaluated, and compared with that of EDTA. The selectivity aptitude of the biodegradable chelants towards the toxic metals was assumed from the speciation calculations, and a proportionate correlation was observed at neutral pH. Pre- and post-extractive solid phase distributions of the target metals were defined using the sequential extraction procedure and dissolution of metals from the theoretically immobilized fraction was witnessed. The effect of competing species (Al, Ca, Fe, Mg, and Mn) concentrations was proven to be minimized with an excess of chelant in solution. The highlight of the outcomes is the superior decontamination ability of GLDA, a biodegradable APC, at minimum chelant concentration in solution and applicability at a wide range of pH environments.     

Effect of pre-harvest foliar application of amino acids and seaweed (Ascophylum nodosum) extract on growth,yield, and storage life of different bell pepper (Capsicum annuum L.) cultivars grown under hydroponic conditions

The study was set up to evaluate the efficiency of amino acids and seaweed on vegetative growth, reproductive phase, yield, and postharvest storage quality of hydroponically grown bell pepper cultivars “Sven Rz F-1” and “Red Knight.” Different concentrations of amino acid and seaweed were sprayed on bell pepper plants under hydroponic conditions. Pre-harvest foliar application of amino acids and seaweed significantly increased plant height, number of leaves, leaf area, yield per plant, number of marketable fruits per plant, average fruit diameter, fruit wall thickness, and average single fruit weight. Amino acid and seaweed significantly improved postharvest physicochemical quality of both bell pepper cultivars under extended cold storage conditions. Conclusively, amino acid as well as seaweed extract not only improved growth, development, yield, and overall quality of bell pepper cultivars but also increased storage life with reduced weight loss and decay along with better physicochemical quality.     

水黄皮叶斑病的成因、严重性及杀菌剂防止

对孟加拉国4个苗圃(IFES、IFESCU、BFRI和ANC)内水黄皮叶斑病症状和严重性进行了调查,结果表明:IFESCU苗圃内叶斑病侵染率及致病指标最高、BFRI次之、ANC最低.与叶斑病相关联的组织从发病植株分离出来,被分离的真菌形成致病性.结果证实胶孢炭疽菌即为致病菌.观察了杧果炭疽病菌丝体生长抑制性并对杀菌剂(Bavistin, Cupravite and Dithane M-45) 有效性和浓度(0.05, 0.10, 0.50, 1.00, 1.50 和 2.00%)进行了鉴定.0.05% Bavistin和Cupravite潜伏8天后,菌丝体生长分别处于最低和最高水平.结果表明:Bavistin杀菌效果最好、Diathane M-45次之,Cupravite对菌丝体生长的抑制作用最低.图1表4参27.     

Optimizing fertilizers doses and their effects on photosynthesis and biomass yield of Hibiscus cannabinus cultivated on BRIS soil

In tropical climate, huge amount of fertilizer need to be used for the cultivation of kenaf (Hibiscus cannabinus L.) in Beach Ridges Interspersed with Swales (BRIS) soil, however this approach is not cost effective and environmental friendly. Therefore, the optimizing of fertilizer rate for BRIS soils and selection of suitable soil amendments are crucial to get a higher yield. In this study, the effects of different combinations of urea, chicken manure and biochar on soil properties, growth performance and physiological characteristics of kenaf cultivated on the BRIS soil were investigated. Eight treatments were conducted namely: control (T1), biochar (T2), chicken manure (T3), urea (T4), chicken manure + urea (T5), biochar + chicken manure (T6), urea + biochar (T7) and biochar + chicken manure + urea (T8). The biomass and physiological characteristics of kenaf were recorded every month, while the soil was analyzed following a standard laboratory procedure. The application of organic and inorganic fertilizer (urea) significantly increased the nutrient content of the soil compared to the T1, whereas T3 showed the highest pH, cation exchange capacity, and exchangeable bases (Na, Mg, Ca). However, the mixing of biochar with organic and inorganic fertilizers showed the highest plant height, diameter of stem and number of leaves as well as dry biomass compared to other treatments. Furthermore, the application of nitrogen fertilizer significantly increased the photosynthesis rate and stomatal conductivity. The results suggest that the mixing of biochar with organic and inorganic fertilizers represents an effective approach for the cultivation of kenaf in tropical climate.     

Sodium alginate supplementation modulates gut microbiota,health parameters,growth performance and growth‐related gene expression in Malaysian Mahseer Tor tambroides

This study investigated the effects of sodium alginate supplementation on gut microbiota composition, health parameters, growth performances and growth‐related gene expression of Malaysian mahseer. Five test diets were formulated by supplementing 0%, 0.1%, 0.2%, 0.4% and 0.8% sodium alginate. Triplicate groups of juvenile Tor tambroides (2.19 ± 0.05 g) were stocked in 15 aquaria (20 individuals per aquarium) and fed at 3.0% body weight per day for 60 days. PCoA and UPGMA analysis showed that gut bacterial community were more convergence in higher sodium alginate‐supplemented diets. The percentage of Porphyromonadaceae, Bacteroides, Plesiomonas and Shewanella were substantially higher and Aeromonas, Entomoplasmatales and Prevotellaceae were drastically lower in higher sodium alginate (0.2%–0.8%) diets. Sodium alginate supplementation (≥0.2%) significantly improved the haematocrit value and respiratory burst activity of T. tambroides. Growth performances and feed utilization were significantly higher in 0.2%–0.4% sodium alginate‐supplemented diets. The increased growth rate of T. tambroides was governed by both hyperplastic and hypertrophic muscle growth. Real‐time PCR data demonstrated that most of the growth‐related genes were significantly upregulated in 0.2%–0.4% sodium alginate‐supplemented diet. Finally, it can be concluded that sodium alginate should be supplemented at 2 g/kg in practical fish feed formulation.     

Resynthesis of Brassica napus L. for self-incompatibility: self-incompatibility reaction, inheritance and breeding potential

Self-incompatibility (SI) in Brassica has been considered as a pollination control mechanism for commercial hybrid seed production, and so far has been extensively used in vegetable types of Brassicas. Oilseed rape Brassica napus (AACC) is naturally self-compatible in contrast to its parental species that are generally self-incompatible. Introduction of S-alleles from its parental species into oilseed rape is therefore needed to use this pollination control mechanism in commercial hybrid seed production. Self-incompatible lines of B. napus , carrying SI alleles in both A and C genomes, were resynthesized from self-incompatible B. oleracea var. italica (CC) cv.'Green Duke' and self-incompatible B. rapa ssp. oleifera (AA) cv. 'Horizon', 'Colt' and 'AC Parkland'. All resynthesized B. napus lines exhibited strong dominant SI phenotype. Reciprocal cross-compatibility was found between some of these self-incompatible lines. The inheritance of S-alleles in these resynthesized B. napus was digenic confirming that each of the parental genomes contributed one S-locus in the resynthesized B. napus lines. However, the presence of two S-loci in the two genomes was found not to be essential for imparting a strong SI phenotype. Possible use of these dominant self-incompatible resynthesized B. napus lines in hybrid breeding is discussed.     

二穗短柄草叶绿体RNA编辑位点的预测及其鉴定

RNA编辑是陆生植物叶绿体转录后基因表达调控的一种重要方式。为进一步探讨单子叶植物RNA编辑功能及其发生机制,本研究通过生物信息学方法,对二穗短柄草叶绿体的81个蛋白编码基因的RNA编辑位点进行了预测和鉴定分析,结果发现78个基因存在编辑位点,共检测到176个编辑位点,都是C到U的转换。其中ndhB最多,为14个编辑位点。为验证预测结果,利用blast工具比对了NCBI的二穗短柄草EST数据库,最终确定存在于17个基因中的34个编辑位点是真实存在的,其中19个为沉默编辑,15个为有效编辑。与5个不同单子叶禾本科物种18个蛋白编码基因的RNA编辑位点的比较发现,在rpoB-206位点,只有二穗短柄草发生了编辑,且只有ndhD-295(293)为部分编辑位点。     

耐高温陆地棉品种综合评价及优良品种选择

 在高温干旱条件下,通过大田试验测定20个陆地棉花品种的主要产量性状、纤维品质性状及农艺性状,并进行综合评价。应用主成分分析法对20个品种的皮棉产量、生育期、株高、始果节、果枝数、有效铃、铃重、衣分、纤维长度、整齐度、麦克隆值、伸长率和断裂比强度进行分析。确定了主要性状的5个主成分及其主成分的函数方程和主成分综合函数方程,主成分的方差累积贡献率达到84.087%。通过计算主成分值和综合主成分值,对供试的20个品种进行了比较,进而选择了湘YC₃F₁、晋棉38、豫宝8号3个综合性状优良的品种,其结果与实际相一致。