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
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.
Sharma M.P.,Soybean Research |
Gupta S.,Soybean Research |
Sharma S.K.,Soybean Research |
Vyas A.K.,Soybean Research |
Vyas A.K.,Indian Agricultural Research Institute
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.
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.
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.