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- Author or Editor: Donald N. Maynard x
Abstract
Quality of horticultural crops is an extremely variable and perhaps nebulous characteristic. Quality may be easily expressed in physical terms such as size, color, or shape. Texture, food value, and keeping qualities, requiring more sophisticated determinations, are also critical components of quality. In some cases, quality may be a highly individual thing, varying from consumer to consumer. Furthermore, the expression of quality may be controlled by genetic capability as well as a host of environmental conditions.
Traditional varieties and selections of tropical pumpkins have long trailing vines that produce two to five fruit weighing from 2 to 20 kg each. Bush inbreds have been developed from crosses between `La Primera', `La Segunda', and `Seminole' with `Bush Butternut'. These inbred plants produce four to 10 early-maturing fruit weighing 1 to 2 kg each at the crown of the plant. Hybrids made with the vining types produce plants that have short or intermediate-length vines. Fruit are produced at the crown and on short laterals on the short-vine hybrids and on laterals on the intermediate-vine hybrids. Some short-vined and intermediate-vined hybrids produce higher yields than the traditional type, but fruit size is smaller and the fruit wall is generally thinner. C42-1-9-1 x Linea C. Pinta, an intermediate-vine type, produced the highest yield in spring (66.5 t·ha–1) and fall (39.9 t·ha–1) at Bradenton, Fla. About three fruit weighing 4 to 5 kg each were produced per plant.
Abstract
Fall and spring spinach experiments were conducted in the greenhouse in sand culture. Nutrient stress was produced late in the growth period by removal of N, P, K, Ca, or Mg from the nutritional regime. Nitrogen stress caused a general restriction in growth and chlorophyll concentration while dry weight was reduced by P and K stress only in the spring experiment. Element stress generally resulted in lower concentrations of that element in mature leaves in the fall and in both mature and immature leaves in the spring investigation. Redistribution generally occurred at a sufficient rate to prevent lower element concentrations in the fall but not in the spring study. K, Ca, and Mg accumulated in mature spinach leaves while N and P were found in higher concentrations in immature leaves.