Sugarbeet yields unaffected by afternoon wilting

The Relationship of Heterodera schachtii Population Densities to Sugarbeet Yields.

Sugarbeet yields were contpared with field populations of Heterodera schachtii Schmidt. The correlation between sugarbeet yields and viable larvae/g of soil was negative and high, but that between sugarbeet yields and viable cysts/g of soil was lower. Sugarbeet yields were also compared with H. schachtii populations by years of rotation with a nonhost crop. The coefficients of correlation (r) b...

The Relationship Between Population Density of Heterodera schachtii, Soil Temperature, and Sugarbeet Yields.

In two glasshouse experiments, relations between sugarbeet root dry weight (y, expressed as a percentage of the maximum dry root weight), and preplanting populations of Heterodera schachtii (P(i)) were described by the equation y = 100(Z)(P(i)-T), in which Z = a constant slightly smaller than 1, and T = the tolerance limit (the value of P(i) below which damage was not measureable). T varied wit...

Afternoon Break

Physics Develops Unaffected by Constructivism

The way physics and other parts of science work can be explained in the framework of radical constructivism. However, this constructivist view itself shows that a uniquily accepted epistemology, constructivism or any other, would not be an advantage for the development of science. Unlike physics some parts of science successfully use constructivist concepts inside their theories. Because this i...

Invasion of Sugarbeet Leaf Blades by Larvae of Heterodera schachtii.

Although Polychronopolis and Lownsbery (1) found that Heterodera schachtii invaded the radicle, hypocotyl, and cotyledons of seedling sugarbeet, they observed no histological or cytological changes other than cellular death and disorganization. Ross (2) reported development of females and brown cysts accompanied by formation of giant cells and hypertrophy in leaves of white clover inoculated wi...