News Article | May 17, 2017
Extension specialists recently released a two-year, multi-state study to measure the effectiveness of insecticide treatments in providing protection against soybean aphids. Credit: Purdue University Entomology Extension About 89.5 million acres of soybeans will be planted across the United States in 2017—a record high, according to the USDA. Research published in the April 2017 issue of Pest Management Science indicates that many of these soybean growers will invest in neonicotinoid insecticide seed treatments. The two-year, multi-state study revealed that, even during periods of infestation by the key pest across the region, the soybean aphid, the neonicotinoid treatment produced the same yields as using no insecticide at all. The study was a joint effort of Purdue University, Iowa State University, Kansas State University, North Dakota State University, the University of Minnesota, South Dakota State University, and the University of Wisconsin. The research was grower-funded, using soybean checkoff funds provided by the North Central Soybean Research Program (NCSRP). The neonicotinoid insecticide thiamethoxam, which is applied as a coating to soybean seeds, provides a maximum of two weeks of protection against insect feeding. Aphids typically don't reach damaging numbers until much later in the season, said Christian Krupke, an entomology professor and extension specialist at Purdue University and one of the researchers and authors of the study. As a result, when soybean aphid populations reached threshold levels, from late July to August, the insecticide levels in tissues of neonicotinoid-treated soybean foliage were similar to plants grown from seeds without the insecticide. Bruce Potter, Insect Pest Management (IPM) specialist for the University of Minnesota Extension, said one of the most important aspects of the study was providing soybean growers information about how to invest their funds. Potter said soybean growers in northern regions, including Minnesota, don't have chronic and consistent economic infestations of early season insect pests. "Farmers wouldn't get an advantage from putting insecticide on soybean seeds," he said. The exception to this conclusion would be fields at a higher risk for infrequent pests like seed corn maggot and white grub or for seed production fields where bean leaf beetle and bean pod mottle virus occur. The research study concluded soybean farmers in all the regions in the study should employ the IPM approach, combining scouting and foliage-applied insecticide where necessary. "In terms of long-term sustainability and the bottom line for your yearly balance sheet, the IPM approach is the most effective approach for pest management in the growing season," Krupke said. A study examining neonicotinoid seed treatments of corn had a similar result. This study, published in the journal PLOS ONE in March 2017, was conducted by Krupke's doctoral student, Adam Alford. It revealed that concentrations of the insecticide most commonly applied to corn seeds, clothianidin, declined rapidly and approached zero in plant tissues within 20 days after planting. Less than 5 percent of what was applied to the seed was recovered from corn plants in the field. Currently, at least one of two neonicotinoids, clothianidin or thiamethoxam, are routinely applied to more than 80 percent of the corn and over half of the soybeans grown in North America. Previous studies, although smaller in size, had shown similar results with neonicotinoid seed treatments, which were introduced in the 1990s, said Kelley J. Tilmon, state extension specialist for the Ohio Agricultural Research and Development Center and an associate professor of entomology at Ohio State University. She performed the research in South Dakota when she was on the faculty of South Dakota State University. The recent study was launched to provide more definitive scientific answers across a large geographic area, Tilmon said. Janet J. Knodel, extension entomologist and associate professor at North Dakota State University, said the results were similar in North Dakota. "As part of our research, we saw the soybean aphids coming into the field in late July and early August in North Dakota," she said. "By then, the residual of the insecticide seed treatment is gone." Explore further: Neonicotinoid seed treatments produce higher soybean yields in the Southern US More information: The Effectiveness of Neonicotinoid Seed Treatments in Soybean. www.edustore.purdue.edu/item.asp?Item_Number=E-268-W#.WRCw1BLDGM8 Christian H. Krupke et al. Assessing the value and pest management window provided by neonicotinoid seed treatments for management of soybean aphid (Matsumura) in the Upper Midwestern United States, Pest Management Science (2017). DOI: 10.1002/ps.4602
News Article | November 22, 2015
A South Dakota State University fisheries scientist is developing a soy protein feed that's tasty and easily digestible to eventually reduce the industry's need for using wild-caught fish as food for farm-raised fish. Much of the tilapia, Atlantic salmon and catfish that Americans toss into their shopping carts are raised in fish farms, where companies traditionally feed them pellets containing anchovy, menhaden and herring. The harvest of those small species has pretty much flat-lined, SDSU professor Mike Brown said, and humans' increased demand for fish has driven up the cost of creating the pellet feed. "We've fully exploited that resource," he said, noting that the goal is to create a more sustainable—and cheaper—food source. Traditional fish feed is currently costing between $1,450 and $2,000 per ton, while soybean meal runs about $425 per ton, Brown said. But some environmentalists worry that feeding fish species an uncommon food source could produce excess waste that muddies up inland tanks or offshore waters where fish are raised. Toying with soy also has the potential to open new markets to soybean farmers dealing with stockpiles that have driven down prices, said Jeremy Freking, executive director of the South Dakota Soybean Association. The South Dakota Soybean Research & Promotion Council has invested $1.7 million into the ongoing work at South Dakota State, which is being commercialized at the site by Prairie AquaTech. Researchers at the Brookings facility have been working with species including coho salmon, rainbow trout, barramundi, white leg shrimp, yellow perch and hybrid striped bass to see how much of the feed can be added to the species' diets without affecting physiology or reducing growth. The goal in agriculture and aquaculture is to have 100 percent of an ingredient digested, absorbed, metabolized and incorporated into muscle tissue, Brown said. Through pre-treatments and microbial fermentation, his research team has been able to increase fish's ability to digest more than 95 percent of the protein and energy, he said. "It's pretty darn efficient," said Brown, who's been setting up small commercial validation trials as researchers work toward putting their product into the marketplace. But if soy protein-based food results in excess waste, aquaculture could become even more damaging to the environment, said Patty Lovera, assistant director of the Washington-based sustainability group Food & Water Watch. "If it's not the food they're built to eat, how do they tolerate it?" she asked. It's also important to look at the entire environmental footprint—and industrial fish farms already have a pretty large one, Lovera said. Plus, she added, the equation would have to include all the factors going into crop production. "Nothing's free in terms of environmental impact," she said, "so you have to count the soy production system in whatever you're calculating there." Explore further: Alternative fish feeds use less fishmeal and fish oils
Sharma M.P.,Soybean Research |
Gupta S.,Soybean Research |
Gupta S.,Research Scholar Microbiology |
Sharma S.K.,Soybean Research |
And 2 more authors.
Indian Journal of Agricultural Sciences | Year: 2012
The aim of present study was to evaluate the impact of tillage practices and crop sequences on AM fungal propagules, infectivity potential and soil enzyme activities in the soybean rhizosphere of a long-term field trial maintained since 2001. Rhizosphere soil and root samples of soybean were drawn in kharif 2008 from three tillage systems (conventionalconventional (C-C), conventional-reduced (C-R) and reduced-reduced (R-R) and four soybean-based crop rotations (soybean-wheat (S-W), soybean-wheat-maize-wheat (S-W-M-W), soybean-wheat-soybean-wheat-maize-wheat (S- W-S-W-M-W) and soybean+ maize-wheat (S+M-W) which are being maintained in split plot design for the past seven years. On completion of six cropping seasons, significantly higher mycorrhizal spore count (17.0/g soil) and infectivity potential (IP) (4.58 IP/g soil) were observed in soybean grown under S-W-M-W rotation under C-R tillage system. However, the per cent root length colonized by AMF was found highest (12.66%) in S+M-W rotation under C-R tillage system. In general, the S+M-W or S-W-M-W rotations under R-R tillage system showed higher soil dehydrogenase activity (3.96 pKat/g soil) and fluorescein diacetate hydrolytic activity (110.76 pKat/g soil) when compared to other combinations. The inclusion of maize in the rotation irrespective of tillage systems showed comparatively higher phosphatase activities. Higher soybean grain yield (3 008 kg/ha) although not significantly higher was recorded in S+M-W rotation under C-C tillage, followed by same rotation (2 814 kg/ha) under C-R tillage system when compared to all other combinations. Moreover, IP of resident AM fungi in soybean rotation involving maize in conservation tillage was found to be highly correlated (r=0.96 to 0.99) with grain yield of soybean and maintaining higher organic carbon which indicates the functioning of resident AM fungi in enhancing the soybean yield.
News Article | October 12, 2016
Harold N. Trick, professor of plant pathology; Timothy C. Todd, instructor of plant pathology; and Jiarui Li, research assistant professor in plant pathology, have designed and patented a soybean variety that protects from nematode parasitic infestation. Soybeans are the second largest crop in the U.S. and bring in about $37 billion each year. But nematode parasites—the No. 1 soybean disease in the nation—plague the crop with stunting, chlorosis, wilting and higher susceptibility to other diseases. The new variety from Kansas State University could potentially save the soybean industry millions of dollars per year. "Basically, we've designed a soybean variety that fights back against parasites," Trick said. "It affects nematodes by stopping their reproduction cycles." The researchers identified genes in nematodes that are necessary to the parasite's function and survival. They then developed a soybean variety that silences those genes. "We have found a solution that controls nematodes and is more durable and broadly applicable than traditional resistance," Todd said. "The other really cool thing about this approach is it's specific to the nematode, so no one has to worry about it causing any type of damage beyond stopping the parasite. It's very environmentally friendly." The patent was issued to the Kansas State University Research Foundation, a nonprofit corporation responsible for managing technology transfer activities at the university. The project received seed funding from the U.S. Department of Agriculture and also has been funded by the North Central Soybean Research Program and the United Soybean Board. The work continues to receive funding from a long-term supporter, the Kansas Soybean Commission. The researchers' next steps are to continue refining the soybean variety, identify a commercial partner and make the crop variety available to farmers. Their approach also showed promising results for controlling nematodes in anthurium, a floral plant, so the technology could potentially control nematode problems in other crops as well, according to Li.
News Article | April 13, 2016
For more than 500 million years, the majority of land plants have shared their carbohydrates with arbuscular mycorrhizal fungi that colonize their root systems, Bücking explained. In exchange, these fungi provide plants with nitrogen and phosphorous and improve the stress resistance of their hosts. These fungi, which are seen as living fossils, explore the soil with their hyphae in the search for nutrients and deliver these nutrients to their hosts. As reward, the host plant transfers anywhere from 4 to 20 percent of its photosynthetically fixed carbon to these mycorrhizal symbionts. "We think these fungi have the potential to increase the biomass production of bioenergy crops and the yield of food crops and do so in a more sustainable and environmentally friendly way," said Bücking. She studies these interactions in food and bioenergy crops including wheat, corn, soybeans, alfalfa, clover and perennial grasses, such as prairie cordgrass. Her research has been supported by the National Science Foundation, South Dakota Wheat Commission, Sun Grant Initiative, Soybean Research and Promotion Council and the U.S. Department of Energy - Joint Genome Initiative. Supply and demand determine the amount of nutrients that plants and fungi exchange in these mutualistic relationships, according to Bücking. To unravel these complex interactions, she collaborates with researchers at the Vrije Universiteit in Amsterdam and the University of British Columbia as well as other South Dakota Agricultural Experiment Station researchers. Though a host plant is colonized by multiple fungi species simultaneously, the plant is able to distinguish between good and bad fungal behavior and allocates resources accordingly," she said. These fungi cannot be enslaved by one particular host plant and form common mycorrhizal networks that give them access to multiple hosts. Her research, for example, showed that when fungi were able to choose between a shaded and a non-shaded host plant, fungi responded by reducing their nutrient share to the shaded plant because this host plant was not able to provide as much carbon as the non-shaded plant. Interestingly, it has recently been shown that plants use these common mycorrhizal networks also as information highways, and are able to "communicate" and to exchange warning signals from one plant to another. She and her collaborators have also found that some fungi are more beneficial than others. For example, Bücking and her collaborators evaluated the relationship between alfalfa and 31 different isolates of 10 arbuscular mycorrhizal fungal species. They then classified the fungal isolates as high-, medium- or low-performance isolates. The researchers found that high-performance isolates increased the biomass and nutrient uptake of alfalfa by more than 170 percent, while the low-performance ones did not have any effect on growth. However, those that benefit one crop may not provide the same nutrients or benefits to another crop species, she cautioned. "Even different isolates of one fungal species can behave differently, and it will be necessary to identify fungi that are optimally adapted to their specific environment and host plant to get the highest plant benefit. In addition to providing nutrients, these fungi can protect food and bioenergy crops from environmental stresses, such as drought, salinity and heavy metals, and diseases, Bücking explained. "All the stresses that a plant can potentially be exposed to are generally improved by mycorrhizal interactions." Increasing tolerance through conventional breeding generally targets only one specific stress factor, but crops are often subjected to multiple stresses simultaneously, she pointed out. "These fungi, if used efficiently, can provide the plant with an improved resistance against stresses that are often difficult for us to predict." However, she added, more research is necessary to better understand how this ancient symbiosis between land plants and fungi can be used to its full potential.
Rani A.,Soybean Research |
Verma K.,Soybean Research |
Saini R.,Kurukshetra University
Indian Journal of Genetics and Plant Breeding | Year: 2012
Transgenic plants of an Indian soybean (Glycine max L. Merrill) cultivar JS335 were obtained using Agrobacteriummediated transformation. Half seed explants were inoculated with A. tumefaciens strain EHA 105 harboring pBI121 containing β-glucuronidase (GUS) reporter gene and neomycin phosphotransferase (nptII) as selectable marker gene. Selection of regenerated primary plants was carried out in a medium with sub-lethal dose of kanamycin (100-175 mg/L). Transformed plants were recovered with a success rate of 0.91%. Stable integration and expression of transgenes in T 0 plants were confirmed by southern blot and histochemical assay respectively. The T 0 plants were fully fertile, with no apparent phenotypic abnormalities. Analysis of the T 1 progeny and T 4 plants from four independent events showed the stable inheritance of GUS gene.
Ramteke R.,Soybean Research |
Singh D.,Soybean Research |
Murlidharan P.,Soybean Research
Indian Journal of Agricultural Sciences | Year: 2012
Field experiments were conducted during 2008 and 2009 using 90 genotypes to screen for height of insertion of the lowest pod, the trait useful for combine harvester. Data was recorded on plant height (cm), height of insertion of the lowest pod (cm) when erect, lodging of the plant in degrees (ø), stem diameter (cm), number of nodes, number of branches and yield. Results of analysis of variance showed significant differences among genotypes in terms of traits under study, which indicate the existence of genetic variation. Correlation coefficient indicated that the grain yield was not significantly associated with all studied traits, which showed non-significant association. Plant height and nodes were negatively correlated with lodging of plants in degrees. First pod height was significant and positively associated with height as well as number of nodes/plant. Stem diameter was positively associated with the nodes/plant. Highest yield was observed in genotypes JS 95-60, Co Soya 2, JS 71-05, MACS 450, VL Soya 21, MAUS 47, KB -79, MAUS 81, PS 1225, NRC 37 and MAUS 71 and was found at par with JS 95-60. However, the genotypes JS 71-05, MAUS 47, PS 1225, NRC 37 and MAUS 71 had a yield at par with JS 95-60, with the lodging angle in degrees (> 65.00°), having pod height above 12 cm, these genotypes are recommended for mechanical harvesting.
Ramteke R.,Soybean Research |
Murlidharan P.,Soybean Research
Indian Journal of Agricultural Sciences | Year: 2012
For the establishment of distinctiveness among Indian soybean [Glycine max (L.) Merrill] varieties, 20 characters were used and presented in a simple tabular form. The varieties were characterized for 20 characters, viz. flower colour, hypocotyl anthocyanin pigmentation, seed colour, absence or presence of pod pubescence, pod pubescence colour, plant growth type, pod colour, days to maturity, seed cotyledon colour, days to 50% flowering, seed size, seed shape, leaf colour, plant height (cm), seed hilum colour, seed lusture, plant growth habit, pod shattering, leaf shape and peroxidase activity. Of the 92 soybean varieties studied, 42 varieties were found to be distinctive on the basis of eleven essential characters. Remaining 50 varieties can be classified into 19 groups. However, 13 of these groups were distinct from each other on the basis of other remaining nine characters. But one group (4 varieties, viz. MAUS 1, PK 308, PUSA 20, and PUSA 37) belonging white flowered and five groups (10 varieties, viz. RKS 18 and RAUS 5, MAUS 47 and Monetta, ADT 1 and Co 1, MACS 57 and Pusa 16, Gujarat Soybean 1 and Punjab1) belonging purple flowered could not be differentiated being similar traits and therefore it is suggested to use of other biochemical markers/ DNA finger printing. This study will be useful for breeders/ researchers/ farmers to identify soybean varieties and to seek protection under Protection of Plant Varieties and Farmers Rights Act.