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December 31, 1998

Imazamox could be used postemergence in snap beans at 0.024 lbs ai/A with little risk of yield reduction provided it is applied at or after the 4' trifoliate. Imazamox adequately controls pigweed, nightshade, and many grass weeds at this timing and rate.

Objectives:

  • Varietal tolerance to Imazamox
  • Weed control and snap bean yield with postemergence Imazamox 
December 31, 1998

OBJECTIVE for 1998:

  • To evaluate the use of pre-sidedress testing of soil nitrate content (PSNT), and the SPAD leaf chlorophyll meter, to predict the level of additional N needed to grow a sweet corn crop to good yield and quality. 

COOPERATORS:

  • Neil Christensen, Dept. of Crop and Soil Science 
  • Marvin Kauffman, consultant
  • Carol Miles, Washington State University Extension

 

December 31, 1999

This proposal is also submitted to the broccoli, cauliflower, and sweet corn research committees of the Oregon Processed Vegetable Commission

OBJECTIVES:

  • To maintain, evaluate, and refine a regional pest monitoring network for selected Lepidopteran pests of broccoli, cauliflower, and sweet corn.
  • To strengthen the communication network among ag professionals serving the Willamette Valley processed vegetable industry.
December 31, 1999

Objectives

The general objective of the processing component of this research is to support the green bean breeding program being carried out by Dr. Jim Myers in the Horticulture Department. The specific objectives are:

December 31, 1998

The cause(s) of the root/crown rot problem of sweet corn in the Willamette Valley the past 10 years has been a challenge to identify. Root rot is the precursor to crown rot symptoms. Many species of Fusaria and Pythium have been isolated from symptomatic roots and crowns.
Experiments were conducted in the field and greenhouse in 1998 to help pinpoint the pathogenic agent of corn root rot and to evaluate the efficacy of soil treatments on managing this disease.

December 31, 1999

OBJECTIVE for 1999:

  • To evaluate SPAD response curves to available N for three varieties of sweet corn and to determine the relative N uptake efficiency of these varieties when grown at varying levels of soil nitrate content.
December 31, 1999

The cause of sweet corn root rot has been difficult to determine. Extensive sampling and surveying indicate the fungal pathogens Pythium arrhenomanes and Fusarium oxysporum and solani are consistantly associated with diseased roots.

Experiments were conducted during 1999 to determine: 1) if the cause of root rot of sweet corn is biotic, 2) if the disease is associated with plant nutrition, and 3) the potential role of stress in disease development and 4) the effect of soil treatments on reducing severity of root rot symptoms.

COOPERATOR:

December 31, 1999

Objectives:

December 31, 2000

Several root-invading plant pathogens have been found in symptomatic sweet corn roots, Fusarium oxysporum, F. solani, and Pythium species, but their involvement in the symptoms observed in the field was still unclear (Powelson et al., unpub.) in the spring of 2000.

Objectives:

December 31, 2000

Objectives for 2000:

  • To evaluate the N uptake efficiency of sweet corn varieties.
  • To evaluate the effects of several fall-seeded and overseeded (relay interplanted) triticale, fall-seeded triticale plus common vetch, and overseeded red clover, on yield of sweet corn fertilized at three rates of N. The cover crops follow snap beans with three rates of N.
  • To evaluate the effect of the cover crops and the N applied to the sweet corn on the amount of nitrate leached below the root zone.
December 31, 2000

While Fusarium oxysporum and solani and Pythium arrenhomanes are consistantly associated with diseased roots and Pythium arrhenomanes has been shown to be pathogenic on sweet corn seedings in the greenhouse, other studies suggest neither fungus alone is the cause of this disease. Experiments were conducted in 2000 to determine: 1) pathogenicity of Fusarium isolates and other fungi on sweet corn seedlings, 2) effect of soil treatments (fungicides and herbicides) on severity of root necrosis of corn grown in naturally infested field soil, and 3) effect of c

December 31, 2001

Principal Investigator: Alexandra Stone
Graduate Student: Heather Darby

SUMMARY

December 31, 2000

Objectives:

  • Breed Bush Blue Lake green bean varieties with high economic yield.
  • Improve pod characteristics including straightness, color, smoothness, texture, flavor and quality retention, and combine with delayed seed size development.
  • Incorporate white mold resistance, and improve root rot tolerance while maintaining resistance to bean common mosaic virus.
  • Initiate populations to facilitate molecular marker assisted selection of desirable horticultural traits.
  • Evaluate novel genetic traits of potential benefit.
December 31, 2001

Objectives: Characterize su and se sweet corn hybrids for reaction to root/crown rot.
 

December 31, 2002

Objective: The purpose of this research was to verify fungicide performance observed in the previous two years.

December 31, 2001

Objectives:

 

These experiments in 1979 were a continuation of a series begun in the 1977 growing season and repeated in 1978. Bush beans, lettuce, and carrots were again the crops used to determine the effects of soil pH and N fertility level on vegetable yield. In 1979, new plots were established with lime rates of 0, 2, 4, and 6 tons/acre. This produced a narrower range of pH (5.0 to 5.8) than was present in the 1977 and 1978 experiments (4.9 to 6.6).

Methods

In 1971, the North Willamette Agricultural Experiment Station obtained several selections from the forcing rhubarb varieties Victoria and German Wine from Washington State University as well as the variety Crimson and several breeding lines from Oregon State University, Corvallis, for a total of 24 lines. All lines were propagated by crown division and five plants of each maintained until 1977. Based on previous observation at WSU and OSU and field observations of vigor and quality at the North Willamette Station, 18 lines were selected in January 1978 for further observation.

February 1, 1985

Prices paid for rhubarb are usually highest at the beginning of the production season. Growers would benefit from an inexpensive and reliable method for forcing crowns into early production. Hot house forcing has been used but this practice is expensive and the field must be replanted. Clear plastic mulch has been used to force rhubarb in the field but mulch costs may exceed $200/acre and plastic removal and disposal are an additional expense.

The purpose of this study was to investigate the effect of several combinations of soil pH and nitrogen fertilizer rates on yield and mineral uptake of bush beans, carrots, and crisphead lettuce. Of particular concern are the nutrient elements potassium, calcium, phosphorus, magnesium, zinc, and copper, and heavy metals such as manganese which may be toxic to plants if present in sufficient quantity. Optimal soil pH levels are not well known for many vegetable crops and probably vary with soil type, cation exchange capacity, amount of organic matter etc.

Drift or volatilization of chlorophenoxy herbicides with resultant damage to non-target plants is an increasing problem in the Willamette Valley. The number of damage claims is increasing each year despite growing regulation and training of growers and applicators. The effects of lethal doses of the chlorophenoxy 2,4-D on broadleaf plants are well-known, but except for a few crops such as tomatoes and grapes, the effects of sublethal doses have not been well documented.

April 1, 1982

Rhubarb growers would benefit from an inexpensive, reliable method for forcing crowns into early production and increasing yields. Early harvests of high quality spears allow growers to take advantage of the usually higher early season prices. Currently, two methods are commonly used to bring rhubarb into early production. In the first, crowns are dug, removed to a hot house, and forced under etiolated conditions. In the second, rows of crowns are covered in the field with clear plastic mulch which increases air and soil temperatures and results in early spear growth.

April 1, 1982

Previous experiments at the North Willamette Station (1979, 1980) have established that stands of carrot, cauliflower, and lettuce on Willamette silt loam are inhibited at pH less than 5.8 compared to higher pH. In addition, broadcast applications of N fertilizers have reduced stands when compared with unfertilized soil. In the 1979 experiments, ammonium sulfate at 112 kg N/ha depressed stands by approximately 15% to 45%, depending on the crop; at 224 kg N/ha, ammonium sulfate depressed stands by 30% to 55%.

February 1, 1985

Overwintered onions in the Willamette Valley are seeded in early September and harvested in the following spring or summer. Obtaining strong and early growth in the spring is essential to achieve large bulb size and profitable yields. However, soil and air temperatures are usually less than optimal during the spring growth period, possibly limiting response to fertilizers.

April 1, 1981

Production of commercial nitrogen (N) fertilizers depends on fixing atmospheric N, a process which consumes natural gas. As world energy prices soar, the cost of fertilizer N must also increase, making efficient crop uptake of applied N ever more important. It may be possible to increase the efficiency of crop N utilization by splitting the total crop requirement among two or more applications. In some situations, application of the entire crop N requirement at one time may lead to significant losses to volatilization, leaching, or runoff.

Introduction

The rationale for this trial was similar to that of the previously described broccoli and sweet corn experiments. Sweet corn is planted at smaller populations and wider row spacings than is broccoli and may be less effective at taking up applied N. The purpose of this trial was to determine if yield of sweet corn would be affected by placement or source of N fertilizer at several rates of applied N.

Methods

April 1, 1981

Lettuce is difficult to plant to stand, particularly in early spring and again during mid-summer periods of high soil temperature. Transplanting greenhouse-grown seedlings may offer the advantage of nearly ideal stands and even permit one extra crop during the growing season. Other possible advantages which may offset the cost of raising transplants include elimination of thinning equipment or labor, reduced herbicide use or cultivation, and production of a more uniform head of lettuce.

Methods

April 1, 1981

Soil and plant samples taken from 90 sweet corn fields in the Willamette Valley during 1978 showed low Cu and B levels but responses to applied Cu and B in commercial fields have been inconsistent. Yields and maturity dates of sweet corn in the Willamette Valley are known to respond to banding P fertilizer at planting. The yield response to various rates of banded P in the presence of high P soil test is unknown. High rates of P and Cu may be antagonistic.

February 1, 1985

Recent experiments at the North Willamette Station indicated that, for a given level of N, yields are increased by delaying application of the bulk of the N fertilizer until the corn is 10 to 12 inches tall. These experiments used ammonium nitrate as N source and the late applied N was sidedressed on the soil surface. No additional benefit was obtained by delaying application of a portion of the N until tasseling or silking. The yield increase with split application of N could be from leaching of NO3-N below the root zone when all N is applied at planting.

Introduction

Although we have established that cauliflower is more efficient that sweet corn or snapbeans in taking up fertilizer N, the large amounts of N applied to this crop (up to 300 pounds/acre) make it a candidate for improvements in N use efficiency. As with sweet corn, a predictive test of the need for late-season N applications could enable growers to cut back on wasteful and environmentally sensitive overapplication of N fertilizer.

Methods

April 1, 1982

Shallots may be grown as an overwinter or spring-planted crop in the Willamette Valley. Major cultural problems in this crop include weed and disease control, effect of planting dates on yield, maturity, and degree of bolting, and the effects of size of, planting stock and planting density on yield and bulb size at harvest. This study was designed to investigate the effects of three planting densities and two bulb sizes on the total yield and mean bulb weight at harvest and on the number of bulbs produced per bulb planted.

Methods

Introduction

Broccoli is not often transplanted in the Willamette Valley, but transplanting offers advantages in multiple cropping and establishing an early stand. The cost of using plug-grown transplants can be reduced by using the smallest plug capable of producing a quality transplant, thus reducing greenhouse bench space, number of trays, and amount of rooting medium needed to produce the crop. In addition, costs might be reduced further by growing multiple seedlings per plug and reducing the number of plugs needed to transplant a given area.

February 1, 1985

Production of muskmelons in the Willamette Valley is limited by low air and soil temperatures, particularly early in the growing season. Daily minimum temperatures are commonly between 50 and 55°F even during the warmest months.

February 1, 1985

Transplanting lettuce seedlings can insure a nearly perfect stand. In addition, transplanting offers the possibility of bringing the crop to market earlier than a direct-seeded crop, taking advantage of higher early season market prices and allowing marketing over a longer time period. Perhaps more importantly, transplanting may allow for multiple cropping. In the Willamette Valley, for example, transplanting would allow three rather than two crops of lettuce. Transplanting may also take place when soil conditions would not allow direct seeding.

April 1, 1986

In an attempt to confirm results obtained in 1979, the cultivars Armado April and Preminda (Royal Sluis Co.) were seeded on August 1, 16, and 30, 1979, and were transplanted on August 28, September 10, and October 8, respectively. Nitrogen rates, in addition to the base fertilizer at planting, were 1) 50 pounds N/acre sidedressed as ammonium nitrate on February 12 and again on March 7, 1980, and 2) 100 pounds N/acre on the same dates. Plots were 4 rows x 25 feet and treatments were in randomized block design.

April 1, 1986

In northern states, spinach is normally planted in early spring for late spring harvest or in late summer for autumn harvest. Spring plantings are often limited by the difficulty of working cold, wet soils and many varieties bolt in the long daylengths and increasing temperatures of late spring. Autumn crops must be established during periods of very high soil temperature and low soil moisture and require frequent irrigation.

February 1, 1985

This trial is the fourth in a series of winter cauliflower variety trials dating from 1978. Previous trials have established that best quality is obtained with varieties that mature in April or May in average years. Very early varieties are less hardy, often fail to produce sufficiently large frames to support large heads, and may suffer frost damage to the curd. Several varieties maturing in late May and June have good yield potential but poor curd quality. This trial focused on mid-maturity varieties to determine those with the best combination of yield and quality.

May 1, 1987

Trials to evaluate the heat tolerance of cauliflower have been conducted at the North Willamette Station for several years. These trials were transplanted in late May for July harvest. The 1985 trial differed in that the varieties were transplanted in early July for late summer to early autumn harvest. As with the earlier trials, the major desired quality is the ability to withstand high temperatures without ricing or discoloration while producing a high density, moderately sized head.

Methods

February 1, 1987

In the N source trial, the number of bulbs harvested per plot varied significantly with treatment, but the stands may have varied before the treatments were applied (Table 4). Total yield varied with N source, but the differences were not directly proportional to stand differences. Mean bulb weight and percent No. 1 bulbs were greatest with ammonium sulfate, in spite of a greater than average stand. They were lowest with ammonium chloride, in spite of a low stand. The high percentage of No.

May 1, 1987

Storage onions in western Oregon have been grown almost exclusively on lake bottom soils which are high in organic matter (more than 10%). Recently, production of onions on mineral or "upland" soils with low organic content and N availability has increased rapidly and now equals production on the organic soils. Response of onions to nitrogen rate and to applications of phosphorus and potassium on the mineral soils is not well understood.

February 1, 1987

The major cultural problem in overwintered onion production is weed control. Onions are a slow-growing crop which competes poorly with weeds. Since the crop is in the ground for eight or nine months, and cultivation is nearly impossible during the winter rainy season, both good weed control at planting and good postemergence control are necessary. The weed control task has been made more difficult by the loss of registration of effective preemergence herbicides such as propachlor.

May 1, 1987

Crop protection with floating row covers interferes with tillage or other means of weed control. Therefore, herbicides or ground mulch are the likely means of weed control under covers. A successful weed control program depends on understanding the environmental and physiological interactions between the herbicide and other components of the cropping system. Results in 1983 with bunching onions (N. S. Mansour) indicated that paraquat residues on row covers might injure the subsequently emerging crop.

February 1, 1987

Extremely high quality leeks are being produced on a small scale in the Willamette Valley with good yields. The crop is usually seeded in early spring, matures in autumn, and can be held through the winter for harvest the following spring. Very few varieties are grown commercially and the highest quality plants have been transplanted and grown in trench culture. The most lucrative market is the restaurant trade, which demands long, thick, blanched stems. Healthy foliage can also be used decoratively in presentation of restaurant dishes.

July 1, 1988

Introduction

Black plastic ground mulch and row covers have enhanced the growth and yield of many crops. Lily bulb production in the Pacific Northwest takes place on bare ground. The objective of this research was to study the effects of a ground mulch and a hoop-supported row cover (tunnel), as well as flower bud removal and cut flower harvest, on bulb growth and bulblet production of Asiatic lily.

Methods

May 1, 1987

Control of virus-vectoring insects, particularly aphids, is essential in production of potatoes for seed to exclude viruses such as potato virus Y, leaf roll, and net necrosis. Seed production fields are heavily treated with insecticides to prevent virus transmission, but control is often inadequate. Floating row covers may protect plants from attack by insect vectors, reducing the need for insecticides. Row covers might also increase yield through their effect on air and soil temperatures around the plants.

July 1, 1988

Introduction

May 1, 1987

Introduction

The purpose of this trial was to investigate the effect of Kimberly Farms row cover on the yield and earliness of broccoli, muskmelon, and tomato.

Methods