Plant Pathology Commons^™

Spraying Tree Fruits, C. C. Wiggans, E. H. Hoppert

Nebraska Agricultural Experiment Station: Historical Circulars

The production of sound, clean fruit is unquestionably one of the major problems facing the modern fruit grower. Culture may be neglected and pruning delayed for a time but the omission of sprays for even a single season demonstrates their absolute necessity. This applies equally to the commercial grower and to the farmer or gardener who has only a few trees.

The Influence Of Various Soil Factors Upon Potato Scab Caused By Actinomyces Scabies, R. W. Goss

Nebraska Agricultural Experiment Station: Historical Research Bulletins

Scab, caused by Actinomyces scabies (Thaxt.) Giiss., is a potato disease of major importance in western Nebraska. Seed treatments are effective in controlling seed-borne scab, but it has been shown that even when healthy or treated seed potatoes are used the disease may be very severe because of infection from the soil. Crop rotation will reduce the incidence of the disease, but the fact that potato scab may cause serious loss in soils never before planted to potatoes indicates that there are numerous factors other than the time interval between potato crops which affect the occurrence of the disease. A …

Tuber Development In Triumph Potatoes As Influenced By Time Of Planting On Dry Land In Northwestern Nebraska, H. O. Werner

Nebraska Agricultural Experiment Station: Historical Research Bulletins

Triumph potatoes were planted on four different dates during six years in order to determine the best planting date on dry land in northwestern Nebraska, where this variety is grown primarily for seed. Features considered in comparing the merits of these planting dates were: stand of plants; vine growth; disease prevalence; time of plant maturity; number, size, and shape of tubers; cracking at harvest time; prevalence and severity of common scab; total yields and yields of various grades of potatoes from various harvesting dates; weight loss in storage; and duration of the dormant period. The experimental aspects dealing with the …

The Symptoms Of Spindle Tuber And Unmottled Curly Dwarf Of The Potato, R. W. Goss

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The differentiation of the virus diseases of the potato on the basis of symptoms is an important but difficult phase of the virus problem. A knowledge of the variation in symptoms due to environmental factors is necessary both in investigational work and in the practical application of our knowledge to the control of these diseases in the field. A fairly comprehensive knowledge of the masking effect of certain environmental factors upon the symptoms of the mosaic group has been obtained through the work of various investigators. Considerably less information is available concerning the effect of environment upon the symptoms of …

Seed Potato Treatment Tests For Control Of Scab And Rhizoctonia, R. W. Goss, H. O. Werner

Nebraska Agricultural Experiment Station: Historical Research Bulletins

Potato scab annually takes a very large toll from the potato growers of Nebraska. Rhizoctonia causes considerable loss each year, particularly in the early-potato sections, where it decreases stand and yield. These losses are caused by infection from both the soil and the seed. The investigations reported in this paper deal only with the control of the infection arising from the seed. Even though potato seed treatments have been recommended for many years, the diversity of recommendations being made at present by various agencies is very confusing to the grower and research worker alike. Many of the reports from different …

Effect Of Cultural Methods And Maturity Upon The Seed Value Of Eastern Nebraska Potatoes, H. O. Werner

Nebraska Agricultural Experiment Station: Historical Research Bulletins

Seed potatoes as good as northern stocks have been produced under a straw mulch in eastern Nebraska by experimenters and growers. Occasionally reports are heard that a lot of seed potatoes has been grown in eastern Nebraska by ordinary cultural methods for many years, apparently without loss of vigor or yielding capacity. In view of this situation it seemed advisable to investigate this problem to determine whether, and to what extent, environment and maturity as such influence the productivity of seed potatoes and also whether it is feasible to produce satisfactory seed potatoes in the southern and eastern portions of …

The Spindle-Tuber Disease As A Factor In Seed Potato Production, H. O. Werner

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The lines of experimentation that supplied the data herein reported, stated in very general terms, were as follows: (1) Tuber-line selection studies (2) Relation of environmental conditions to seed-potato production (3) Seed-potato strain trials of certified and uncertified stock (4) Spindle-tuber transmission experiments. Most of these general lines of experimentation will not be completely discussed as a unit in any one part of the bulletin. For the sake of clarity, consecutive thought, and elimination of repetition, data will be selected from any experiment for insertion and discussion under the most logical heading in any part of the bulletin. Unless otherwise …

Further Studies On The Effect Of Environment On Potato Degeneration Diseases, R. W. Goss, George L. Peltier

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The identification of potato degeneration diseases in the field is extremely difficult owing to the number of diseases now described, their manifestation on different varieties, the combination of several diseases on the same plant, and the further splitting up of these combinations into separate diseases. The influence of environmental factors in intensifying or inhibiting the symptoms of these diseases also increases the difficulty of diagnosis. In the present investigation the effect of environmental factors has been studied with the purpose of determining the limiting factor or factors in the masking of the symptoms, in the hopes of simplifying a complex …

Bulletin 122 - Fruit-Fly: Description And Control, L. J. Newman

Bulletins 1 - 2999

IT is a fundamental principle of Economic Entomology that, in order to successfully combat an insect, the life history of that insect must be worked out. A feature common to all insects is a series of stages involving distinct changes of form which succeed each other in a definite order.

An insect like the fruit-fly affords no exception to this universal rule. Beginning with the fly, we have in regular succession—Egg, Larva, Pupa, and finally the fly again. These stages represent what is known as the life cycle of time insect. Each change—such as larva to pupa, pupa to fly—is …

Seed Potato Investigations, H. O. Werner, R. F. Howard

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The objects of the investigations reported in this bulletin were:

• To determine the condition of western Nebraska seed stock by the tuber unit method and by comparative trials in western Nebraska and various other points.
• To determine the effect of culture, place, disease, etc., upon seed value.
• To perfect methods of applying results to seed production in western Nebraska.

Spraying Experiments In Nebraska, J. Ralph Cooper

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The more important questions which were considered during the three years covered by the present report were as follows: 1. How many summer sprays are required and when should they be applied? 2. What is the difference in efficiency between various brands of arsenate of lead? 3. What are the relative values of lime sulphur and Bordeaux as fungicides for spraying apples? 4. Is it possible to lessen or prevent Bordeaux injury and at the same time control fungous diseases? 5. Is it possible to interchange Bordeaux and lime sulphur in a spray schedule in such a manner as to …