Basal stem rot of oil palm incited by Ganoderma species: A review

European Journal of Plant Pathology - Populus davidiana × Populus bolleana (PdPap) root rot caused by Fusarium oxysporum is a major disease in China. Controlling this disease...     

Intracellular calcium release mediated by sphingosine derivatives generated in cells

Soluble and hydrophobic lipid breakdown products have a variety of important signaling roles in cells. Here sphingoid bases derived in cells from sphingolipid breakdown are shown to have a potent and direct effect in mediating calcium release from intracellular stores. Sphingosine must be enzymically converted within the cell to a product believed to be sphingosine-1-phosphate, which thereafter effects calcium release from a pool including the inositol 1,4,5-trisphosphate-sensitive calcium pool. The sensitivity, molecular specificity, and reversibility of the effect on calcium movements closely parallel sphingoid base-mediated inhibition of protein kinase C. Generation of sphingoid bases in cells may activate a dual signaling pathway involving regulation of calcium and protein kinase C, comparable perhaps to the phosphatidylinositol and calcium signaling pathway.     

Host factors, occupation, and testicular cancer in Saskatchewan, Canada: 1979-2002

The incidence rates of testicular cancer are increasing in several countries, especially among younger adults. The role of agricultural exposure in the etiology of testicular cancer is contentious. We extracted information related to the host, lifestyle, and tumor characteristics from the files of the Saskatchewan Cancer Agency for all cases (n = 517) of testicular cancer diagnosed in Saskatchewan between 1979 and 2000. The following questions were the subject of this initial inquiry: (1) Are tumor characteristics similar or different among occupational groups dichotomized into farmer/nonfarmer? (2) Are host characteristics similar or different among occupational groups? (3) Is farming as an occupation one of the independent predictors of tumor stage at diagnosis? Statistical analyses were restricted on 486 cases. The nonfarmers (n = 349) had smaller tumors in length on average, and more of them were diagnosed at stage I compared to farmers (n = 72). Occupation was not recorded for 65 cases. Farmers were older than nonfarmers. In logistic regression analyses with adjustment for relevant variables as cited in the literature, individuals with nonseminomas [OR (95% CI) 1.99 (1.30-3.31)] and < or = 26 years old at diagnosis [2.12 (1.15-3.93)] were significantly more likely to be diagnosed with a stage 2 or higher tumor. Farmers were significantly more likely than nonfarmers to be diagnosed at stage 2 or higher [1.76 (1.00-3.10)]. Based on our data, the significant predictors of being diagnosed with stage 2 and higher are: presence of nonseminoma, < or = 26 years old, and farming as an occupation.     

Exogenous cholesterol prevents cryocapacitation-like changes,membrane fluidity,and enhances in vitro fertility in bubaline spermatozoa

A study was conducted to determine the optimum dosage of the exogenous cholesterol-loaded cyclodextrins (CLC) to get maximum cryoprotection for bubaline spermatozoa. In the present study, 120 × 10⁶ spermatozoa were incubated in 2, 3 and 4 mg of CLC as grouped as Gr II, III and IV, respectively, and sperm progressive motility, intracellular Ca²⁺, capacitation status by protein tyrosine phosphorylation (PTP) assay and zona binding per cent (ZBP) and cleavage rate (CR) of the cryopreserved buffalo spermatozoa by in vitro fertility assay were assessed in comparison with an untreated control group (Gr I). Results revealed that there was a significant (p < .05) linear decrease in percentage of sperm population with higher intracellular Ca²⁺ and percentage of sperm population with medium or high capacitated by PTP in CLC treated from 2 to 3 mg and then increased to 4 mg/120 × 10⁶ spermatozoa whereas sperm progressive motility, percentage of sperm population with low capacitated, ZBP and CR were increased significantly (p < .05) in sperm population treated from 2 to 3 mg CLC and then decreased to 4 mg/120 × 10⁶ spermatozoa. The study has clearly indicated that CLC at 3 mg/120 × 10⁶ spermatozoa has maximum beneficial effects in protection of sperm progressive motility, membrane fluidity (low intracellular Ca²⁺); prevention of cryocapacitation (low capacitation pattern in immunolocalization) and enhancement of in vitro ZBP and CR. Post-thaw motility of the CLC-treated sperm has shown positively significant (p < .05) correlation with sperm population with low intracellular Ca²⁺, low capacitated sperm population, ZBP and CR, whereas it was negatively (p < .05) correlated with sperm population with high intracellular Ca²⁺, medium or high capacitated sperm. The present study has revealed for the first time that incubation of spermatozoa with CLC of higher dose (>3 mg/120 × 10⁶ spermatozoa) had adverse effects on sperm cryopreservation, although incubation of sperm with 3 mg/120 million prior to processing had minimised the freezing–thawing-associated damages in bubaline species.     

Ameliorative effect of Lantana camara biochar on coal mine spoil and growth of maize (Zea mays)

The aftermath of surface mining is a wasteland deprived of vegetation, soil structure and biodiversity. The unearthed overburden material is nutrient deprived and can only support the growth of invasive weeds such as Lantana camera which often cause allelopathy. The aim of the study is to prepare biochar from these noxious weeds and use it as an amendment for the mine spoil reclamation. Lantana biochar (LB) was prepared and applied to mine spoil, and Zea mays L. growth on biochar amended mine spoil was monitored for three months. Biochar application in a coal mine spoil using LB is comparatively de novo approach for reclamation practitioners. LB was prepared at varying temperature (250, 350 and 450℃) and residence times (30, 45 and 60 min) and characterized. After characterization, the most recalcitrant biochar at 450℃ for 60 min was chosen for application for the study. A pot trial was conducted to study the effect of LB at 0, 5, 10, 20 and 30 g kg⁻¹ dosage on the yield of Zea mays and mine spoil properties. Significant ameliorative effects were observed with increase in organic carbon content (2.9 times), cation exchange capacity (2 times), water holding capacity (0.13 times) and decrease in bulk density (0.5 times) in the mine spoil. The seedling vigour index and germination also increased significantly (p < .05) at 30 g kg⁻¹ biochar treatment compared to control. The study concluded that LB has the potential to remediate coal mine spoils and promote re-vegetation in degraded land.