Improvement of plant

All varieties of crops that are grown have some desirable characteristics or they would be not used. Nevertheless, each of these varieties is known to possess one or more undesirable traits which, if eliminated, would result in higher yields and better quality. The aim of the plant breeder is to develop superior varieties by eliminating the undesirable characteristics and combining the desirable ones in the same variety. The characteristics desired vary with the crop and the conditions under which it is to be grown. For example, with barley the characteristics that are considered by the plant breeder are malting quality and nature of the ones while what he desires with wheat may be winter hardiness, protein content and milling quality. In some areas, early maturing cold-resistant varieties are needed, while in others, later maturing, heat-and drought –resistant varieties will do best. In all cases yield and resistance to major disease and insects are important.

The most important items are of concern to the plant breeder are as follows:

1. Resistance to (a) diseases, (b) insects, (c) heat, (d) cold, and (e) drought.

2. Proper maturity.

3. Good yield.

4. Improved plant quality for (a) animal feed, (b) human food, and (c) industrial use.

5. Plant characteristics: (a ) strength of straw or stalk, (b) height of plants, (c) shattering of seed, (d) leafness, and (e) ability to recover following grazing or when out for hay.

Упражнение 9. Ответьте на вопросы.

1. What is the aim of the breeder?

2. What the desired characteristics depend on?

3. What are the most important items which of concern to the plant breeder?