Corn with Symptoms of Reddening: New Host of Stolbur Phytoplasma.

Recurrent epiphytotic outbreaks of a disease of uncertain etiology known as reddening of corn (Zea mays) have occurred in some areas of Serbia during the last 50 years. Affected plants show early and abnormal ripening, dry precociously, and have poor, shriveled grains. Using molecular tools, phytoplasmas were detected in diseased plants and their identity was subsequently deduced as a subgroup 16SrXII-A strain by a variety of supporting assays involving restriction fragment length polymorphism (RFLP) analysis of polymerase chain reaction (PCR)-amplified 16S rDNA and tuf gene sequences, selective amplification of phytoplasma DNA using primer pair G35p/m, similarity of 16-23S intergenic spacer region (SR) sequences, and similarity and phylogenetic analysis of 16S rDNA gene sequences.

Gibberellic acid nitrite stimulates germination of two species of light-requiring seeds via the nitric oxide pathway.

We used two species of light-requiring seeds, Paulownia tomentosa, which have absolute light requirement (no germination in darkness), and Stellaria media seeds, which germinate in darkness to a certain extent because of presence of preformed active phytochrome, to obtain results strongly suggesting that gibberellic acid nitrite stimulates seed germination via its capability as a functional NO donor. Exogenous application of gibberellic acid nitrite stimulates gibberellin-insensitive Stellaria media seed germination in darkness as do a wide variety of NO donors. Pure gibberellic acid could replace the light requirement of P.

Sublethal effects of tebufenpyrad on the eggs and immatures of two-spotted spider mite, Tetranychus urticae.

Sublethal effects of the mitochondrial electron transport inhibitor (METI) tebufenpyrad on Tetranychus urticae Koch females surviving treatment as eggs or immatures (> or =90% mortality) were investigated in life-table assay. The developmental time of females that had survived treatment as eggs (2 mg/l) or larvae (2.5 mg/l) was 1 day longer, while that of protonymphs (2.

The effects of clofentezine on life-table parameters in two-spotted spider mite Tetranychus urticae.

Sublethal effects of the growth inhibitor, clofentezine, on life-table parameters of Tetranychus urticae Koch females treated at different developmental stages with a concentration causing >90% mortality were investigated. Females which survived treatment as 'early' (0-24 h old) eggs produced 12% more offspring than the untreated females during the first five days of oviposition. This resulted in a significant rise in the intrinsic rate of increase (rj): 0.