Glenn C. Wright

Vermicompost leachate reduces some negative effects of salt stress in pomegranate

PurposeGrowth and productivity of plant crops are negatively affected by salt stress. Vermicompost leachate (VCL) has beneficial effects on plant growth in several different ways. This experiment was conducted to investigate the potential of VCL for raising the tolerance of pomegranate against salinity.MethodsA pot experiment was organized to analyze some physiological attributes and antioxidant activities of two Iranian pomegranate cultivars under different concentrations of NaCl with or without VCL.ResultsSalinity negatively affected the growth properties of pomegranate, while foliar spray of VCL-induced salt tolerance by reducing the accumulation of Na+ in the seedlings. Leaf area and shoot and root fresh and dry weight of VCL-treated pomegranate plants showed a significant increase regardless of whether the seedling growth was under non-saline or saline conditions. Chlorophyll loss and reduced photosynthesis efficiency caused by salinity were also ameliorated using VCL. Foliar application of VCL also improved the activity of antioxidant enzymes and caused a reduction in oxidative stress and electrolyte leakage.ConclusionsThese results suggested that VCL could alleviate the damage caused by salt stress in pomegranate by limiting the agglomeration of Na+ and amending the activities of antioxidant enzymes by which the efficiency of plant increases.

A molecular approach for the diagnosis of wood rotting disease in desert citrus

Brown heartwood rot is an increasingly important problem in southwestern deserts, affecting numerous native tree species, and commercial lemon production. Two fungal pathogens, Coniophora ere- mophila and Antrodia sinuosa, have been identified as causal agents of brown heartwood rot in citrus. Development of effective disease management strat- egies relies on the ability to readily identify and dis- tinguish between the pathogens; therefore we have developed molecular markers as an alternative to morphometric methods to differentiate these two economically important pathogens. Random ampli- fied polymorphic DNA analysis identified four prim- ers that revealed fungal polymorphisms. Polymorphic DNA fragments were cloned, sequenced, and used to create a 700 bp sequence characterized amplified re- gion (SCAR) in C. eremophila isolates using sequence- specific primers, Conio7 and Conio8. Three frag- ments (300, 650, and 1000 bp) were amplified with Conio7 and Conio8 in A. sinuosa isolates. A rapid, small scale method for DNA extraction from fungus was developed to expedite the technique. With this method, the usefulness of the Conio7 and Conio8