Cultivar, defined

Conservative is used to define orchard and management factors that once introduced cannot, or are extremely difficult to, change or require substantial additional investment to do so. Among these are soil and other site-specific conditions, choice of variety/cultivar and rootstock, planting density and tree canopy formation, system stabilisation measures at orchard set-up and installations to buffer extreme events. 

In recent years, a number of workers have published amino acid analyses of the sweet potato (38, 43, 35, 22, 18). The overall picture is that the sweet potato amino acid pattern is of good nutritional quality but that the variability of individual amino acids both within the same cultivar and across cultivars is very high. For example, Walter et al. (44) reported that with the exception of aromatic amino acids, every essential amino acid has a score of less than 100 in one or more cultivars. The amino acid score is defined as the g of amino acid in 100 g of test protein divided by the number of g of that amino acid in the FAO/WHO reference pattern times 100. Bradbury et al. (22) showed that, for the same cultivar, environmental effects on the amino acid patterns is significant. For three cultivars, they found a mean percent standard deviation for all amino acids of 24.2,... 

Ozone and sulfur dioxide mixtures are of special interest, because of their widespread occurrence and the greater than additive effect on Bel W, tobacco. Concentrations of either or both that may cause foliar injury are found around major metropolitan areas throughout the world and are widespread throughout rural eastern United States. Macdowall and Cole reported that the two-gas combination lowered the threshold for injury of tobacco (cultivar White Gold) by sulfur dioxide, but not the threshold for ozone injury. Macdowall et defined the threshold in terms of dose when th reported the threshold at 20 pphm-h (0.20 ppm-h). This has not appeared true in several other reports, nor within the results reported by Macdowall and Cole. Symptoms reported, when sulfur dioxide was below the threshold for the specific plant, were similar to those reported for ozone. 

Studies of pollutant interactions are preliminary. We are still not able to define ad uately the total potential impact of pollutant combinations on the production of quality food, feed, and fiber. We do know that plant species respond differently to pollutant combinations and five. We still do not understand variations in species or cultivar responses or the responses of plants grown or exposed under a variety of environmental stresses. 

The search for sunflower varieties of defined characteristics was also aimed at a reduction of plant size and adaptation to other climates. Short-stature cultivars in... 

For the long period of selection studies we have defined that creation of most productive cultivars in mountain enviroiunental zone by well-known effective methods is unavailable for the cultivars of hayfield-pasture type, because created populations have the main drawback-the low adaptive capacity in conditions of... 

---