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VII. The Future of Sugar Beet Breeding Research

VII. The Future of Sugar Beet Breeding Research

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SUGAR BEET IMPROVEMENT



135



delian factors such as monogermness is being demonstrated, and one can

only speculate on possibilities when genetics research throws light on

other characters in the sugar beet and demonstrates their inheritance.

Polyploidy has at present hardly been utilized with sugar beets as a

genetic tool, but it may be the key opening the way for certain wide

crosses between the species of Beta. The results from European work

that are beginning to come in concerning the productiveness of triploids,

certainly demand thoroughgoing exploration with American varieties.

As indicated, the research in the United States has simply shown that

polyploidy itself is not an automatic way whereby production may be

increased. The finding of highly productive polyploids and their use,

either as tetraploids or as triploids, have not thoroughly covered the

possibilities in this field of research.

The control of certain serious diseases by resistant varieties, although affording a fair measure of assurance against crop failures, is

certainly not a closed matter, because losses are still heavy. We may

forecast that the improved sugar beet in the next two decades will incite

wonder as to why present-day varieties once were prized. As said, control of virus yellows and sugar beet nematode is still to be achieved, but

evidence given by Coons (1952) and Rietberg (1954) indicates that disease resistance breeding may be effective against virus yellows. There

are indications also that breeding research may be useful against the

sugar beet nematode (Rietberg, 1954).

Once certain morphological and disease resistance goals are gained,

or even some half-way point is reached, there remain the great problems concerned in improving the sugar beet as a living machine. There

is a job of making it a better, more efficient sugar producer; reducing its

complement of harmful nitrogen; removing the melassigenic elements;

in short, as physiological research explains the metabolism of the sugar

beet, the breeder must be ready to build on these findings. The sugar

beet needs to be improved in storagability, both with respect to resistance to decay and oxidation rate. These fields of research as investigated by Gaskill (1952b), Stout and Smith (1950), and Nelson and

Oldemeyer (1952) already are showing great promise. I n another

approach to sugar beet improvement, the results given by Wood et al.

(1950) indicate that tolerance to cold exposures may be increased, the

seedlings which have survived subfreezing temperatures giving progenies with greater cold tolerance than the parental material.

The jobs yet to be done serve to make us humble in appraising the

improvements that have been registered. The advances that have come

since the White Silesian beet was picked out by Achard give encouragement in facing the problems of the future.



136



G . H. COONS, F. V. OWEN, A N D DEWEY STEWART



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Green Manuring Viewed by a Pedologist

J. S. JOFFE

New Jersey Agricultural Experiment Station. Rutgers Uniuersity*

New Brunswick. New Jersey

CONTENTS



I. Ideas and Concepts .

1. Introduction

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2 . Historical Analysis . . . . . . .

3 . Pedologic Analysis of the Green Manuring

a . Essence of Pedology . . . . .

b . The Zonality Principle . . . . .

4. Organic Matter and Green Manuring . .

a . Introduction . . . . . . . .

b . Soil Organic Matter Constants . .

c. Fundamental Proposition . . . .

d . Organic Matter from Tops and Roots

I1. Green Manuring in Zonal Soils . . . . .

1. Introduction

. . . . . . . . .

2. Applying the Zonality Principle . . .

I11. Green Manuring in Pedalfers . . . . . .

1. Zone o f Laterization . . . . . . .

a . Organic Matter Supply . . . .

h . Supply o f Nutrients . . . . .

c . Soil Structure Improvement . . .

d. Moisture Relationships . . . . .

e. Residual Value . . . . . . .

2 . Zone of Podzolization . . . . . . .

a . Organic Matter Supply . . . .

b. Supply of Nutrients . . . . .

c. Soil Structure Improvement . . .

d . Moisture Relationships . . . . .

e. Residual Value . . . . . . .

IV. Green Manuring in Pedocals . . . . . .

1. Chernozein Zone . . . . . . . .

a . Burning the Straw in Grain Culture

2 . Soil Types under Irrigation . . . . .

V . Concluding Remarks . . . . . . . .

References

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J. S. JOFFE



I. IDEASAND CONCEPTS

I. Introduction



Green manuring, as discussed in this paper, does not refer to practices and methods of growing crops for purposes implied by the term.

In the main, the object is to assess effects of these practices and methods

in the light of pedology. In general, these effects are reflected in soilplant relationships more or less alike qualitatively, and less so quantitatively, with any type of organic matter that finds its way incidentally

into the soil or is intentionally placed there, such as sod crops, residues

of cover crops, straw o r stubble and roots of grain crops, top growth and

roots not harvested, such as corn stalks, vines of peas, beans, potatoes,

and tomatoes, and organic material brought in from the outside, such

as barnyard manure, peat, by-products of the food industries, sawdust

and wood chips, sewage sludge, composts, wool waste, and others.

Thus, whereas green manuring per se is the focus of the discussions,

the theories advanced and principles evolved may be applied in total

or in part to methods of utilizing any kind of organic matter. These

theories and principles stem from the natural laws governing the processes of soil formation, This is the pedologic approach in the study of

green manuring in the respective zonal soil types, subtypes, and varieties of these.

2. Historical Analysis

Pieters’ volume (1927) Green Manuring, being the most comprehensive presentation on the subject, is universally quoted. Indeed, it

presents a review of the history and development of the many phases of

the green manure problem, going back to practices in China, 1134 B. c.

I n the preface of his volume, Pieters states: “The value of green

manuring lies in the fact that organic matter is worked into the soils.”

Trunz ( 1911) , Stoklasa ( 1926), and Wohlbier ( 1931) , covering investigations on green manuring published in German, stress this very same

fact.

Pieters and McKee (1938) have concluded “that in the main the

object of green manuring must be to maintain rather than to increase

the quantity of organic matter in soils.” Standard texts on soils, agronomy, and horticulture repeat these statements. The men on the land

have accepted the practice. Some have succeeded better than others;

some have failed; and most of them have been asking one and the same

question: “You experts speak of increasing the store of organic matter

in the soil, or of sustaining a suitable amount of organic matter,



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