'r'éiion VeiucfaIIe Ikiest

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1 'r'éiion VeiucfaIIe Ikiest 0- COLLECT(ON Volume 23 Oregon State University, January 1974 Number 1 Sweet corn hybrids evaluated for head smut resistance Resistance to head smut, caused by the fungus Spacelotheca reilianum, has become an important factor to consider in sweet corn variety evaluation. The disease is a limiting factor in yield in many Western Oregon locations and has forced farmers to abandon some fields for sweet corn production. Considering the susceptibility range of all varieties available, the major commercial hybrid, 'Jubilee' is only moderately susceptible. However, this level of susceptibility has apparently permitted a build-up of the smut fungus, accounting for the current problem. Though varieties with much greater resistance have been recognized for several years, the iii Zkis issue.. Sweet corn hybrids evaluated for head smut resistance 1 Bean varieties screened for rust resistance 3 Row spacing affects bush bean yields in Northeast Oregon 4 Early eggplant varieties tested for Western Oregon conditions 5 production and quality characteristics of 'Jubilee' have made it difficult to replace in both processing and fresh market operations. In both 1972 and 1973, varieties included in sweet corn trials at Corvallis were also tested for smut resistance in two infested commercial fields. One near Scio, Oregon, providi smut infection both years. The other plantings, near Corvallis, were in two fields which had a history of bad losses from smut. However, infection was obtained only in the 1972 test. Tables 1 and 2 show a well-defined range of susceptibility among varieties, even though a great variability in the tests is also apparent. This variation, the result of the long plot areas crossing spots of high and low infection intensity in the field, may be due to several factors which have not been identified. Soil moisture may directly affect the infection process, or factors affecting plant growth may indirectly influence the percent of infection. these tests, a plant was counted as infected if there was any detectable symptom, which could range from heavy sporulation in the tassel or ear to a few affected kernels, or could consist of stunting with no normal ear development. (Continued on next page) In

2 Outstanding varieties observed during the two years are 'Goldie', 'Triumphant II', 'Exp 1791', ' ', ' ', 'Code 570', 'Gold Crown', 'Commander'. This is an arbitrary list and others such as 'Stylepak' are also resistant to a useful degree. Other varieties, such as 'Sugar Daddy', 'Spring Gold', and 'XP 1330' are highly susceptible and should not be planted where smut is present. Sources of varieties listed in the tables are as follows: Rogers Bros., P.O. Box 2188, Idaho Falls, Idaho Harris Seeds, Moreton Farm, Rochester, New York Ferry Morse Seed Company, Box 967, Mountain View, California J. Asgrow Seed Company, Kalamazoo, Michigan Northrup King and Company, 1500 Jackson St. NE, Minneapolis, Minnesota Niagra Seeds, Western Research, P.O. Box 2508, El Macero, California Charter Seed Company, P.O. Box 191, Twin Falls, Idaho and G Seed Company, P.O. Box 787, Caldwell, Idaho R. Baggett h'orti culture Department Table 1. Head Smut Susceptibility Trials, Scio and Corvallis, Oregon, 1972 Corvallis1 Sciob Overall Variety Source Avg. 1 2 Ti 4 Avg. Average Gold Crown E Stylepak XP Sugar Daddy NCX Gold Winner Gold Cup B Trail Blazer Northern Belle Goldie Earlibelle Yukon FM Cross Jubilee Code Code Code Code Ex Code Golden Cross B Controls Location average (excluding controls) LPlots 20 ft. long with plants, arranged in 4 rows in randomized blocks 140 feet long (plot area 560 feet lodg). Planted Nay 26, readings on August 23. 2plots 22 ft. long with plants, arranged in 2 rows in randomized blocks 250 ft. long (plot area 1000 ft. long). Planted May 29, readings on August 24. 3Controls from commercial crop surrounding plots. Jubilee at Corvallis, Stylepak at Scio. An average of 8 plots, one from each side of the plot area for each replication. Oregon Vegetable Digest is published four times a year by the Agricultural Experiment Station, Oregon State University, Corvallis, G. Burton Wood, Director. Address correspondence to the author concerned or to the Department of Horticulture. Material may be reprinted providing no endorsement of a commercial product is stated or implied. Please credit Oregon State TJniversity. To simplify technical terminology, trade names of products or equipment sometimes will be used. No endorsement of products named is intended, nor is criticism implied of products not mentioned. 2

3 Table 2. Head Smut Susceptibility Trial, Scio, Oregon, Infection 1972-' Commerc. Plots4 No. Vane ty Source Rep 1 Rej2 Rep 3 Ren 4 Avg. Avg. Avg. % Inf. 1 Goldie Code E Sugar Daddy NCX Code Blitz Triumphant II A Exp S_pring Gold Style.pak Cade g NCX Trail Blazer ' Yukon Strndance : Code JubIlee NCX Sweet Sue Exp NCX Code twiji Golden - Bantam check Commander 4 XP X1P i-plot area was two rows, 1,000 feet long; each variety was in four 22-ft. plots, with plants/plot, arranged in randomized blocks. Planted: June 11, Infection recorded Sept. 11, Check variety score was from the crop of 'Stylepak' surrounding the plots. For each replication one 22-ft. plot on each side of the plots was counted and averaged for the score shown. 3Average from two locations, one in the same field at Scio, one from Corvallis. 4Averages of eight 25-plant plots, randomly taken from commercial trials in the same field at Scio, Bean varieties screened for rust resistance Since bush snap beans have largely replaced pole varieties in the Willamette Valley, the bean rust disease (Uromyces phaseoli) has not been much of a problem. This is chiefly because most bush beans complete their growth during the hottest and driest part of the year and the short growing season provides only a brief time when rust can build up and cause damage. All the bush bean varieties have had some screening for disease resistance and most have a fair degree of resistance to certain races of the rust fungus. Studies conducted in the greenhouse indicated, however, that under conditions favorable to the disease, or when large numbers of rust spores are present, many bush bean varieties may become infected. Frequent surveys during the last 15 years have revealed only a single race of Uromyces phaseoli, race 33, in Western Oregon. In pole beans, rust is common, particularly late in the season. In bush beans, the disease is seldom seen except in very late plantings when the plants are less vigorous and are exposed to infection for a relatively long time. The purpose of these field tests was to determine the relative susceptibility of commonly grown bush bean varieties and some breeding lines to natural infection when exposed to heavy "disease pressura" Each plot consisted of a single row of the test line with an artificially inoculated hill of the susceptible 'Pinto UI 111' 3 feet from each end of the row. Each test row was thus exposed to large numbers of air-borne spores from both ends. The entire test area was surrounded by 2 rows of corn as a windbreak, and the plots were irrigated frequently, using overhead sprinklers. No cultivating equipment was moved through the test area after emergence of the bean seedlings. The plots were seeded May 25, 1973, and disease readings were made August 15, when the pods were fairly mature. The most heavily infected leaves were selected from plants near the center of each row. Readings, therefore, show the maximum disease 3

4 severity at the greatest distance from the source of inoculum. A. card having a hole 1 cm square was placed over a section of the leaf lamina and the number of pustules in the exposed area recorded. In Table 1. Development of rust (Uromyces phaseoli) in bush snap beans exposed to natural field infections under conditions of high infection potential, August 15, 1973 Mean number of2 - Size of Cultivar p ustules per cm pus tules ye howing Pinto UI 111* 45.8 Large Severe Very poor BC ,8 Small Slight Variable B Small Moderate Good Variable Severe Variable BBL 290* Medium Slight Good sma 11 Slight Variable Medium Severe Variab 1$ Variable Slight Poor l90l Large Slight Variable Medium Slight Var iable Ore. 1604* 16.3 Small None Exce ilent La rge Moderate Good Ore. 5 8* 14.1 Medium None Excellent Variable Slidit Variable 5 8-BC Variable None Excellent TempQ* 12.3 Large Shi ght Variable Large None Exce ilent B Variable None Exce 11ent Gallatin 50* 1. 9 Small None Excellent *Commercjal varieties; all others are Oregon State University breeding lines. Although we seldom see rust on any of the snap bean varieties grown in Western Oregon, none is immune and, given favorable conditions for infection, an outbreak of rust of epidemic proportions is possible. In the table, a variety with less than 10 pustules per cm2 would be considered highly resistant, one with less than 15 per cm2 resistant and one with 20 or more per 2 would be considered susceptible to infection by our common rust race 33. Fortunately, most of the varieties tested had a degree of resistance to rust. 'Gallatin 50' was by far the most resistant of the snap bean varieties tested. The few pustules that were present were very small, with no yellow halo and no general yellowing of the leaf lamina. None of the snap beans tested approached the dry bean 'Pinto UI 111' in susceptibility. It required only casual observation to distinguish the 'Gallatin 50' and 'Pinto UI 111' plots from all others. Highest yields of bush beans were obtained In closer row spacings tested in Umatilla County in Row spacings used in two experimental plantings were 7, 14, 21, and 28-inches. Seeding rates were adjusted to increase the number of plants per foot of row as the row width increased. Plant populations at harvest time were 113, 81, 80, and 66 thousand plants per acre for the 7, 14, 21, and 28- inch rows. Plant populations for the three wider row spacings were less than intended. Prior to planting, Trifluralin (3/4 pound/acre) and two rates of fertilizer were incorporated into the soil. Fertilizer rates were and pounds N, P205, K20, S, and Zn per acre to each row spacing. 'Wondergreen 452' bush beans supplied by Rogers Walla Walla, Inc., were planted in early June. Irrigation water was applied via sprinklers. The 4 addition, appearance of the infected leaves and relative size of the pustules was recorded. Results of the tests are given in Table 1. Foliar B4840-F 19.2 Laree None Poor There was remarable uniformity in the number of rust pustules per cm for any particular variety. On the other hand, in some varieties the size of pustu1 and the general appearance of the infected plants varied greatly, possibly indicating that the line was segregating for these characteristics. Greenhouse inoculation of bean breeding lines to determine resistance to rust is a useful procedure, making it possible to eliminate many susceptible lines and to select lines with a high degree of resistance. It is believed, however, that testing for natural infection under field conditions provides a more reliable estimate of the probable performance of a variety under commercial growing conditions. --Edward K. Vaughan Botany and Plant Pathology Department General appearance of plants Row spacing affects bush bean yields in NE Oregon once-over hand harvesting the last of August consisted of counting all plants in a plot and picking and weighing all marketable pods. Sieve size distributiat was determined by putting all pods through a grader at Rogers Wahla Walla plant in Nilton-Freewater. The highest yields were obtained from the narrowest row spacings in each experiment (Table 1). Yields declined rapidly as the row spacings increased with the lowest yields being harvested from the 28- inch rows. Statistical differences in yields in Experiment 1 were measured between the 7, 14, and 21-inch row spacings. The loss of several plots in Experiment 2 prevented the analyzing of that experiment statistically. Blooming and pod set during the growing season were observed to be extended over a longer period of time than usual. This is borne Out by data of sieve size distribution (Table 1). The large percentage of size 1 and 2 pods and low percentage of size 4 suport

5 the field observations. Row spacing had no obvious effect on sieve size distribution of the pods at harvest. No visible differences in growth and color were observed during the growing season which could be attributed to the two rates of fertilizer applied. No difference in yield due to fertilizer was measured. Soil test values showed each soil to be reasonably well supplied with nitrate nitrogen, available phosphorus, and potassium. Available nitrogen as nitrates was approximately 130 and 160 pounds per acre for Experiments 1 and 2 respectively. Table 1. Results of two years' experimental work indicate the yield of bush beans could be increased 40 percent or more by planting rows spaced 7 to 14 inches apart compared to the wider spacing now used. --F. V. Pumphrey Columbia Basin Research Center --D. J. Burkhart Umatilla Extension Agent --N. S. Mansour Extension Vegetable Specialist Yield and sieve size of 'Wondergreen 452' bush beans from four row spacings, Columbia Basin Research Center, 1973 Row Spacing Inches LSD 5% EXPERIMENT 1 Yield Tons! Acre 1& Sieve Size Percent EXPERIMENT 2 Yield Tons! Sieve Size Percent Acre &6 1& & Early eggplant varieties tested for Western Oregon conditions The eggplant is a very marginal crop in Western Oregon because of its high heat requirement for fruit set and development. Even with black plastic mulch, which appears to improve fruit production, popular varieties produce very sparse and variable crops. Most seed firms in the United States list the popular large-fruited varieties, such as 'Black Beauty', which are egg-shaped and have attractive purpleblack color. Because previous trials have indicated that some other types were more adapted to the ares, a few varieties were grown in 1973 without plastic mulch to observe earliness and production. The trial was a small one, with 5 plants of each variety in a 12-foot plot. Greenhouse grown transplants were set Out on May 11 into rows with 600 lb.!acre banded fertilizer. Irrigation was applied every 7-10 days during the summer. Estimates of performance were made by picking all usable sized fruits at arbitrarily determined times. Also noted was the date when the first feasible harvest was possible (such as for a home gardener) and when a full crop was mature. Second harvests were made on some early varieties which continued to produce after the first crop was picked. In the table, the varieties are listed in order of the first mature fruits which is slightly different than the order of first harvest. 'Morden Midget', 'Money Maker No. 1' and 'Money Maker No. 2' are distinctly early. 'Short Tom', 'Long Tom', 'No. 29', and 'Black Jack' are also early when yield of their first harvest on September 13 is considered. Of these 7 varieties, 'No. 29' and 'Black Jack' produce generally typical large, egg-shaped fruits, and those of 'Morden Midget' are also egg-shaped but much smaller. 'Black Jack' was probably the outstanding variety for a combination of fruit type and earliness. The remaining 4 early varieties bear slender fruits which are equal in quality, but are not of the type popular in the United States. If seed companies in this country were to list them, home gardeners or local market growers would do well to try these varieties. The dwarf, early 'Morden Midget' is available from at least one retail source and should permit home gardeners to succeed in many areas where standard varieties fail. Sources of varieties in the trial: Geo. W. Parke Seed Co., P.O. Box 31, Greenwood, South Carolina Takii and Co., Ltd., P.O. Box 7, Kyoto Central, Kyoto, Japan T. Sakata & Co., c,'o Herbst Bros. Seedsmen, Inc., 1000 Main Street, Brewster, New York Stokes Seed Ltd., Box 548, Buffalo, New York Agway, Inc., Ithaca, New York W. Atlee Burpee Co., Box 748, Riverside, California Joseph Harris Co., Moreton Farm, Rochester, New York J. R. Baggett Norticulture Department

6 Eggplant Variety Observations, Corvallis, Oregon, 1973 let Main the. per plant No. fruit per plant Avg. Vartety Source ripe crop Total A Total Wt. Notes Morden Midget Poor, light, streaked color; broad egg Money Ma16Y El J'() a ape var a. a, some cr00 a., color unit, purple None Maker # ,n IT,O Si. rougher fhan Hone Maker P2. lighter y P color: some rrmnkad Short Tom Med. long, many crooked; var. color, black to it. Durnle Long Toe Similar to Short Tom No , tar ge egg shape, some broad; fair color, come stripe Stokes Hybrid fl.69 Broad egg, fair to good color Black -lack S Eg to ned. I ong; good color, good Black Beauty type WRIte Beauty Some green; small, egg shape Large Frui ted # Near globe shape; color fair - some striped and dull Jersey King Hyb ) V. tall plant; long pear shape; un med. purple smooth Earle Hybrid Egg to pear; poor color; generally poor Burpee Hybrid CoccI shape and color; egg shape Special Ilibush ,90 Long-heavy; very good color; smooth Early Purple GeneraUy late and poor performance AGRICULTURAL EXPERIMENT STATION of Oregon State University Corvallis, Oregon Director FREE: Annual Report or Bulletin or Circular or Report of Progress. Permit 1115 POSTMASTER: Please return free if unclaimed. See Postal Laws and Regulations. POSTAGE PAID U.S. DEPARTMENT OF AGRICULTURE AGR 101 THIRD CLASS BULK RT. U.S.MAIL