1999 Research Results

Evaluation of soybean germplasm under Pennsylvania conditions, (Pennsylvania State University), Elwood Hatley, $6,000. Dry conditions and above normal temperatures from May through July caused high variability in the test areas, and some trials were not reported for that reason. The Landisville site, in Lancaster County, is used to evaluate material in Groups III and IV in full season and double crop plantings. Eighty-three private and nine public varieties were evaluated in the full season test, including 39 normal germplasm, 44 Roundup Ready and 7 STS varieties. The double crop test at Landisville included 51 private and nine public varieties, including 27 normal germplasm, 26 RR and 7 STS varieties. Eighteen breeding lines, from the Mid-Atlantic testing program, were evaluated there. Maturity Groups II and early III are evaluated at Rock Springs in Centre County. Fifty-three private and nine public varieties were evaluated in the full season test (which included 32 normal germplasm, 20 RR and 10 STS varieties). The average yields for each test are as follows: Landisville, double crop normal germplasm, 47.2 bushels per acre. Rock Springs, full season normal germplasm, 59.4 bushels per acre; full season RR, 68 bushels per acre; full season STS, 57.3 bushels per acre.

Sclerotinia stem rot (white mold) of soybeans: field testing of agronomic control measures and greenhouse investigations of soybean resistance to Sclerotinia sclerotiorum, (Pennsylvania State University), Barbara Pennypacker, $21,682. There are few soybean cultivars adapted for Pennsylvania that have high levels of resistance to Sclerotina white mold. Field experiments were conducted to test whether agronomic practices can be modified to reduce the impact of white mold. Row widths were 14, 21 and 28 inches. Plant densities ranged from high (150,000 plants per acre) to as low as 75,000 plants per acre. Also tested was the herbicide Cobra, which has shown promise as a management tool. It does not affect the pathogen but stimulates the plant to produce defense compounds. Row width and plant density had no effect on white mold incidence when Cobra was applied, but did significantly affect disease incidence in the absence of Cobra. White mold was reduced in the 21-inch and 28-inch row widths (10 and 2 percent, respectively) when plant density was low. When plant density was increased to compensate for fewer rows per acre, white mold incidence did not drop below 10 percent regardless of row width. When Cobra was applied, disease incidence ranged between 2 and 8 percent regardless of row width or plant density. There was a significant Cobra/plant density interaction in yield. Yields did not differ with plant density when Cobra was applied, but were significantly greater (40.1 bushels per acre) in the high-density treatment compared to the low-density treatment (33.5 bushels per acre) in the absence of Cobra. White mold was below the threshold necessary for yield suppression. Following up on research in 1998, plant size was examined in relationship to white mold resistance. The dry weight of leaves per plant was determined in healthy plants from all treatments. In significant numbers, the greater the leaf dry weight, the lower the incidence of white mold. Plants with greater numbers of leaves may have a higher photosynthetic capacity and thus a greater ability to fix carbon and produce the compounds needed to express resistance to white mold.

Burcucumber management in soybeans and corn, (Penn State University ), W. R. Esbenshade and William S. Curran, $8,043. Experiments were conducted in central and southeastern Pennsylvania from 1997 to 1999 examining the effect of emergence date, tillage, row spacing and herbicides on burcucumber growth, reproduction and management in corn and soybeans. Results suggest that no-till should reduce burcucumber emgergence, that few plants emerge after early July and that several effective herbicides are available for control in soybean and corn. The best herbicides for control in soybean were Classic and Roundup, alone or in combination. In corn, several post-emergence programs such as Lightning and Raptor were ineffective in managing burcucumber. Synchrony, Basis Gold and Exceed provided better than 80 and 90 percent control. Liberty provided effective early control in Liberty-Link corn but lacked residual control. The addition of atrazine increased control in most situations. Row spacing appears to have little impact on the emergence or management of burcucumber. Emergence date also plays a vital role in the growth and development of the weed, as plants emerging in early June experienced tremendous growth and seed production while no burcucumber seed was produced when plants emerged after mid-July in a corn crop.

Effect of herbicide programs on weed shifts in corn soybean rotation, (Penn State University), William Curran, $8,116. Five species of weeds continue to be dominant in both corn and soybean: common lambsquarters, common ragweed, Pennsylvania smartweed, yellow foxtail and yellow nutsedge. Lambsquarters biomass increased in untreated checks but was controlled in both corn and soybean. The ALS post treatment was less effective in 1998 with lambsquarters and ragweed. The Classic/Pinnacle mixture was more effective in 1999 than 1998, but did not provide effective control of lambsquarters or ragweed in soybean. All corn herbicides controlled ragweed. All herbicides controlled smartweed in both crops. Yellow foxtail was effectively controlled except with ALS post treatment in soybeans in 1999. The Assure II mixture did not control all emerged foxtail. A single Roundup application did not control all yellow nutsedge and ALS post treatments were less effective for nutsedge than other treatments overall, perhaps due to the lower rate of Classic used. Weed control was better in 1999 than in 1998, probably because of weather conditions. Species noted in ’99 that were not apparent in ’98 included wild buckwheat, black medic, volunteer corn and soybeans. Also noted were corn chamomile, small flower galinsoga, carpetweed, field pepperweed, witchgrass, white clover, prostate spurge, fall panicum, common yellow woodsorrel, velvetleaf, Canada thistle and prostate knotweed. These species probably represent the seedbank that could shift directions in the future.

Evaluation of food grade soybean varieties and organic cultural practices, (Rodale Institute), Peggy Wagoner, $5,106. A growing demand for soyfoods such as soymilk and other dairy alternatives commands a premium for food grade soybeans of $1.25 to $2 above feed variety prices of $4.5 to $5 per bushel. High quality certified organic food grade soybeans sold for $12 to $16 per bushel in 1999. Food grade varieties tend to yield 20 to 25 percent lower than feed varieties, but newer, higher yielding varieties are now available. On-farm variety trials began in 1998. Yields and other agronomic qualities of four food grade varieties were compared to Pioneer 9352 (Group III), a popular feed variety. Food qualities of the four were compared to Vinton 81, considered the industry standard. The food varieties yielded 13 to 28 percent lower than the Pioneer variety. Iowa 3001 (Group III) produced higher yields than the other food varieties but exhibited significantly lower yields of soymilk and tofu. Food processors prefer varieties such as HP 204 due to higher soymilk and tofu yields, as evidenced in prices of $2 more paid for HP 204 and Vinton 81. The premium paid for food grade varieties more than offsets the slightly lower yield, especially when these varieties are grown under certified organic conditions.

Enhancing the functionality of soy protein ingredients (Penn State University) John Coupland, $18,498. Soy protein isolate is a low-value byproduct of oil manufacture but its functionality in human foods, such as providing texture as a thickened liquid or gel, is limited by its relatively poor solubility, particularly at intermediate pH values. Soy proteins often form an unsightly precipitate rather than a firm gel or smooth liquid. The aim of this research was to develop an enhanced soy protein ingredient by mixing it with small molecule surfactants that will bind to the soy protein and change its functional properties. A commercial soy protein isolate was dispersed in solutions of 0 to 5 percent polyoxyethylene sorbitan monolaurate (Tween 20, an uncharged surfactant) or sodium dodecyl sulfate (SDS, a negatively charged surfactant) and a small volume of concentrated hydrochloric acid overnight. Then the pH and viscosities of the samples were measured. The viscosity of surfactant-free samples was low and largely pH independent. The viscosity of all samples containing Tween 20 was higher, particularly at low pH. The samples containing SDS behaved similarly to the Tween samples under acid conditions but had a higher viscosity under neutral conditions. The SDS samples also significantly enhanced the solubility of soy proteins, especially in the intermediate pH range. Surfactant-enhanced soy protein has new and useful properties that may be valuable to apply in many food products. For example, an acid barbecue sauce could be thickened with modified soy whereas the unmodified soy product would merely precipitate out.

Evaluate the interaction between date of planting, row spacing and cultivare maturity upon soybean production and whole farm crop rotation, (Penn State University), John Yocum and O. E. Hatley, $2,691. The trial was planted, but due to dry weather, the trial was not harvested. The trial was to be replanted in 2000.

Can a cover crop improve continuous soybeans? (Penn State University), John Yocum, $2,153. Grasses were successfully seeded into standing soybeans Sept. 21, 1998. By the end of October, grass plants averaged 31.3 plants (rye) to 106.3 plants (ryegrass) per square foot. Prior to killing the grasses with Roundup Ultra, the grasses were harvested to obtain the amount of dry matter production. Tons per acre were: Rye, 3.6; wheat 1.3; ryegrass, 0.7; timothy, 0.2; oats (killed in winter, 0 production in spring). Soybeans were seeded no-till in 15-inch rows with a corn planter on May 20, 1999. All grasses except spring oats (which was no different than the no-cover check plot) provided good soil cover at planting. At harvest, rye, wheat and ryegrass still had good soil cover. The rye cover treatment produced the only significant soybean yield increase (16.7 bushels per acre) over the yield of the non-cover check. Since the 1999 growing season was dry, the high amount of rye mulch reduced the loss of soil moisture. Since this was the first year, conclusions on soil improvement cannot be made. Rye wheat and grass covers did appear to provide enough soil cover to reduce soil erosion from one soybean harvest to the next.

Soybean response to nitrogen fertilization in conservation tillage: Effect of planting date and nitrogen timing, (Pennsylvania State University), Douglas Beegle and John Yocum, $6,106. Soybeans require 5 pounds of nitrogen per produced bushel. Only half of this is supplied by nitrogen fixation. The study evaluated the response of soybeans to nitrogen fertilization at two critical periods: at planting time and at early pod fill when nitrogen demand is at a maximum. Soybeans were planted in minimum and no-till plots at two locations, both early and mid-season. Two treatments were applied, at rates of 30, 60, 90 or 120 pounds nitrogen per acre. Dry weather hurt the yields at Landisville, where the only significant effect on yield was due to planting date. There, the late-planted beans out-yielded early planted beans by 11 bushels per acre. There was no significant effect of nitrogen fertilizer rate or timing on yield there or at Rock Spring.

The researchers concluded nitrogen fertilization appears to have little beneficial effect.

New uses Extreme pressure metalworking lubricating oils and greases from soybeans, (Desilube Technologies), Dr. James King, $25,000.