Calag Archive

A detailed study of both individual cotton plants and data from the overall performance of large fumigation plots, resulted in convincing evidence that early season infection by Verticillium wilt may drastically reduce yield. Yield reductions were reflected in reduced production per plant and in bolls of lighter weight. Where infection of individual plants occurred from seedling to harvest, and occurred more severely on some plants than on others, yield reductions resulted from the production of fewer bolls per foot of row, and lighter boll weight averages. Fumigation obviously controlled soil-borne pathogens other than Verticillium—some perhaps unknown—so the total effect of fumigation evidenced in the second year may not have resulted from Verticillium wilt control alone. High plant vigor and dense plant populations undoubtedly reduced yields in fumigated plots.

There has been considerable increase in the commercial production of onions on the West Side. In this study, both dehydrator and market onions were evaluated for variety differences, optimum planting times, bulb size, pungency, and length of harvest season at the West Side Field Station near Five Points in 1971.

These experimental results show not only that sugarcane mosaic virus (SCMV) tolerance exists in sweet corn, but also that it is variably expressed in plant and ear characteristics. Virus infection can apparently be expressed independently or collectively in the form of leaf symptoms, in an inability to produce ears of marketable size, and in defects in kernel development on the ears. Some of the hybrids tested showed collectively less defects than others, and should be considered for trial in areas where SCMV infection is prevalent. These are: NCX 200 (Niagara), 70–2109 (Rogers Bros.), Sunshine State (Keystone), and Goldie (Northrup-King). On the basis of very high table quality, past performance, and fairly good tolerance in this experiment, the hybrids Bonanza and Jubilee should also be included in grower trials.

The weather largely determines the use of water, or evapotranspiration (ET), by most crops during times when the plants are healthy and fully shade the ground. Even under full-cover conditions, however, the evapotranspiration of various crops can vary significantly with differences in stomatal or surface resistance, reflectance, and aerodynamic roughness. However, during early stages of crop growth, transpiration is very limited, and the controlling factor in water use is basically the moisture status of the soil surface. How frequently the surface receives water from rain or irrigation—along with the weather conditions—largely determines evapotranspiration rates.