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'S17-2243C' (Reg. no. CV-557, PI 700003) is a semi-determinate, maturity group IV (relative maturity 4.9), non-genetically modified (non-GM) soybean [Glycine max (L.) Merr.] cultivar developed and released by the University of Missouri-Fisher Delta Research, Extension, and Education Center. S17-2243C was developed to meet the growing demands for new non-GM soybean cultivars with high yield and elevated seed oil content. S17-2243C is resistant to stem canker and charcoal rot and has tolerance to salinity conditions. Seed of S17-2243C has averaged 232 g kg(-1) of oil concentration on a dry weight basis, which was significantly higher than all check cultivars in the 2020 USDA Uniform Soybean Tests, Southern States. S17-2243C was tested against high-yielding private and public soybean cultivars from 2018 to 2021 in 80 locations across 12 states, including Alabama, Arkansas, Illinois, Kentucky, Louisiana, Mississippi, Missouri, North Carolina, Ohio, South Carolina, Tennessee, and Virginia. With high yield potential, broad adaptability, early maturity, elevated seed oil content, and non-GM traits, S17-2243C is an excellent cultivar choice for soybean growers adopting alternative growing systems and benefiting from premium prices offered for non-GM soybean products. Missouri Soybean Merchandising Council [6066-21220-014-000D]; USDA-ARS Project; [301] Published version Missouri Soybean Merchandising Council, Grant/Award Number: 301; USDA-ARS Project, Grant/Award Number: 6066-21220-014-000D Public domain – authored by a U.S. government employee

Soybean (Glycine max [L.] Merr.) production is influenced by planting date, but its impact on yield in fields infested with Macrophomina phaseolina (Tassi) Goid. is unknown. A 3-year study was conducted in M. phaseolina-infested fields to assess the effects of planting date (PD) on disease severity and yield using eight genotypes, four of which are reported to be susceptible to charcoal rot (S), and four reported with moderate resistance (MR) to charcoal rot (CR). The genotypes were planted in early April, early May, and early June under irrigated and nonirrigated conditions. There was planting date by irrigation interaction for area under the disease progress curve (AUDPC) where May PD was significantly lower compared to April and June PDs in irrigated environments but not in nonirrigated environments. Correspondingly, yield in April PD was significantly lower than that of May and June. Interestingly, yield of S genotypes increased significantly with each subsequent PD, while yield of MR genotypes remained high across all three PDs. The interaction of genotypes by PD on yield revealed that the MR genotypes DT97-4290 and DS-880 had the greatest yields in May compared to April. While May PD had a decreased AUDPC and an increased yield across genotypes, the result of this research suggests that in fields infested with M. phaseolina, early May to early June planting coupled with appropriate cultivar selection provides maximum yield potential for western Tennessee and mid-southern soybean growers.

Two infectious root diseases that cause significant yield losses worldwide in soybean (Glycine max [L.] Merr.) are charcoal rot caused by Macrophomina phaseolina (Tassi) Goid. and the soybean cyst nematode, caused by Heterodera glycines Ichinohe. The objective of this research was to evaluate resistance to charcoal rot in a set of 120 soybean accessions reported to have resistance to one or more races of soybean cyst nematode so that lines with combined resistance could be identified. These accessions were screened in an infested field in 2006 and 2007. Charcoal rot severity ranged from 1 to 5, where 1 is resistant and 5 susceptible. The results showed that out of the 120 soybean accessions tested for charcoal rot resistance 12 were identified to have moderate levels of resistance, 51 had moderate susceptibility, and 60 were susceptible. Furthermore, the accessions with moderate resistance to charcoal rot had resistance for one to two races of soybean cyst nematode. Within the lines identified with moderate resistance to charcoal rot, nine had a yellow seed coat, a desirable agronomic trait. These lines can be used as parents in soybean breeding programs for developing soybean cultivars with combined resistance to both charcoal rot and soybean cyst nematode.

Charcoal rot, caused by Macrophomina phaseolina, is a major soybean disease resulting in significant yield loss and poor seed quality. Currently, no resistant soybean cultivar is available in the market and resistance mechanisms to charcoal rot are unknown, although the disease is believed to infect plants from infected soil through the roots by unknown toxin-mediated mechanisms. The objective of this research was to investigate the association between seed sugars (sucrose, raffinose, stachyose, glucose, and fructose) and their role as biomarkers in the soybean defense mechanism in the moderately resistant (MR) and susceptible (S) genotypes to charcoal rot. Seven MR and six S genotypes were grown under irrigated (IR) and non-irrigated (NIR) conditions. A two-year field experiment was conducted in 2012 and 2013 at Jackson, TN, USA. The main findings in this research were that MR genotypes generally had the ability to maintain higher seed levels of sucrose, glucose, and fructose than did S genotypes. Conversely, susceptible genotypes showed a higher level of stachyose and lower levels of sucrose, glucose, and fructose. This was observed in 6 out of 7 MR genotypes and in 4 out of 6 S genotypes in 2012; and in 5 out of 7 MR genotypes and in 5 out of 6 S genotypes in 2013. The response of S genotypes with higher levels of stachyose and lower sucrose, glucose, and fructose, compared with those of MR genotypes, may indicate the possible role of these sugars in a defense mechanism against charcoal rot. It also indicates that nutrient pathways in MR genotypes allowed for a higher influx of nutritious sugars (sucrose, glucose, and fructose) than did S genotypes, suggesting these sugars as potential biomarkers for selecting MR soybean plants after harvest. This research provides new knowledge on seed sugars and helps in understanding the impact of charcoal rot on seed sugars in moderately resistant and susceptible genotypes.

Information on the effect of nitrogen fertilizer rates and environment on sesame seed composition and nutrition is scarce. The objective of this research was to investigate the effects of nitrogen fertilizer application rates on sesame seed yield, protein, oil, fatty acids, and mineral nutrition. A two-year (2014, 2015) field experiment was conducted. Nitrogen fertilizer (urea ammonium nitrate) solution (UAN, 32% N) was applied by side dressing to four sesame varieties (S-34, S-35, S-38, S-39) at rates of 44.7, 67.2, 89.6 and 112.0 kg·ha-1. Rate of 44.7 kg·ha-1 was used as control since this rate is traditionally recommended in the region. Increasing nitrogen application rates resulted in higher protein and oleic acid contents in two varieties in 2014, and in all varieties in 2015. Increased protein and oleic acid were accompanied by lower total oil and linoleic acid. Increased nitrogen application also resulted in higher seed N, S, B, Cu, Fe, and Zn in 2014 in S-34 and S-35, but either a decline or no clear change was observed in seed levels of these nutrients in S-38 and S-39. In 2015, increased nitrogen application resulted in significantly higher seed N in all varieties, and higher S, B, Cu, Fe, and Zn in some varieties. A significant positive correlation was observed between nitrogen application rate and yield, and with seed levels of protein, oleic, acid, N, B, Cu, Fe, and Zn. A significant negative correlation was observed between nitrogen application rate and seed oil and linoleic acid. Thus, increased nitrogen fertilizer application resulted in higher seed protein, oleic acid, and some mineral nutrients, but lower oil and linoleic acid. However, this effect depended on variety and environmental conditions. Because higher protein and oleic acid are desirable traits for sesame seed nutritional value and oil stability, regional breeders should select sesame varieties for efficient fertilizer response.

Soybean seed isoflavones are affected by various factors, but their responses to phosphorus (P) fertilization is largely unknown. A field experiment was conducted at Jackson and Milan in Tennessee from 2008 to 2010 to investigate the effects of P application rates on concentrations and production of individual and total isoflavone in the form of aglycones in soybean seeds on low and high P soils under no-tillage. Five P application rates (0, 10, 20, 30, and 40 kg P ha−1) plus the University of Tennessee recommended P fertilizer rate based on initial soil-test P were arranged in a randomized complete block design with four replicates. Phosphorus application rates exerted more frequent and greater impacts on aglycone concentrations on the low testing P soil at Milan, particularly under the dry year of 2008. Application of 10–20 kg P ha−1 was adequate for producing high individual and total aglycone concentrations in seeds on the low testing P soil. Genistein concentration was more responsive to P fertilization than daidzein and glycitein concentrations. Individual aglycone concentrations were positively correlated (r = 0.25–0.91) among each other. Total aglycone was positively correlated with seed protein but not with oil in concentration. In conclusion, pre-plant fertilization of 10–20 kg P ha−1 is frequently beneficial for producing high concentrations of individual and total aglycones in soybean seeds on low P soils, particularly under dry years, without any significant reductions in other key quality attributes such as protein or oil.

Information on the effects of agricultural practices such as seeding rate (S), row spacing (RS), herbicide apical treatment (T), and nitrogen application (N) on soybean seed nutrition (protein, oil, fatty acids, sugars, and amino acids) is limited. Although seed composition (nutrition) constituents are genetically controlled, agricultural practices and environmental conditions significantly influence the amount and quality of seed nutrition. Therefore, the objective of this research was to understand the responses of these seed composition constituents to these practices, the environment, and cultivar differences. Two-field experiments were conducted, in 2015 and 2016, in Milan, TN, USA. The experiments were irrigated with four replications and included: two soybean cultivars, two seeding rates, three different row spacings, two N rates, and Cobra herbicide apical treatment. The results showed significant effects of S, RS, N, and T on some seed composition constituents, including protein, oleic, linolenic, and stearic acids, sugars, and some amino acids. The current research demonstrated that single or twin row with a seeding rate of 40,000 seeds ha&minus, 1 resulted in higher protein, oleic, some sugars, and some amino acids. However, a high seeding rate of 56,000 seeds ha&minus, 1 resulted in lower protein, oleic acid, some sugars, and some amino acids due to plant competition for soil nutrients. Herbicide apical application of Cobra1X resulted in higher linolenic acid and some amino acids. Application of nitrogen resulted in higher protein, linolenic, and some amino acids. This research is beneficial to the scientific communities, including breeders and physiologists through advancing knowledge on the interactions between cultivars and environment for seed nutritional quality selection, and to soybean producers through consideration of best agricultural management to maintain high seed nutritional qualities.

Charcoal rot, caused by the fungus Macrophomina phaseolina (Tassi) Goid., is a disease of soybean (Glycine max (L.) Merr.) that causes yield loss worldwide. The purpose of this research was to dete...

Frogeye leaf spot (FLS), caused by

Charcoal rot (CR), caused by the fungus Macrophomina phaseolina (Tassi) Goid. is a pervasive disease of economic significance on soybeans (Glycine max (L.) Merr.). Similarly, drought is the leading cause of yield loss in soybean worldwide. In this study, CR severity and seed yield were determined in irrigated and non-irrigated environments in 2011, 2012, and 2013 for thirteen soybean genotypes, nine of which were previously determined to be drought tolerant (DT). The objectives were to determine the severity of CR in the putative DT genotypes and to determine the over-all effect of CR on yield in irrigated and non-irrigated environments. Colony Forming Units (CFUs) at reproductive stage R7 were used to assess disease severity and classify each genotype's response to CR. A stress tolerance index (STI) was used to determine the relative impact of soil moisture stress (i.e. no irrigation) on the 13 genotypes. Over all three years in both irrigated and non-irrigated environments, five genotypes were consistently rated as moderately resistant to CR (MRCR) and three genotypes were consistently rated as susceptible to CR (SCR), whereas the responses of the remaining five genotypes varied between MRCR and SCR. Averaged over the three years, there was a wide range (0.36–1.09) of STI values among genotypes. Even though there was a consistent trend, there was a very weak relationship between STI and CFU's at the R7 growth stage. Regression analysis indicated that as CFUs at R7 increased, seed yield decreased, although the relationship was not significant in every year and irrigation environment. Nonetheless, across all years and irrigation environments, a pooled (global) slope indicated a yield loss of 11.5 kg ha−1 for every 1000 CFUs at R7. These data indicated that as CFUs at R7 increased, seed yield decreased in both irrigated and non-irrigated environments. However, as the relationship between CR disease severity and DT was minimal, it may be necessary to select for resistance to both traits using environments where both soil moisture stress and CR are high.

A field study was conducted in 2014 through 2016 at the University of Tennessee Research and Education Center, Milan, TN, to determine fungicide effects on frogeye leaf spot (FLS) caused by Cercospora sojina and to determine disease severity and yield under no-till and tillage. Each plot was visually rated for FLS severity based on the percent leaf area covered from 0 to 100%. The result showed that tillage did not affect severity of the disease or yield. However, there were significant effects from fungicide, year-to-year effects, and fungicide × year interactions. Among the three years, disease severity in 2016 was greater than in 2014 and 2015. Among the six fungicides, Topsin, Topguard, Quadris TOP SBX, and Priaxor significantly (P ≤ 0.05) reduced maximum disease severity in 2016. All fungicide applications improved yield relative to the untreated check. Topsin and Quadris TOP SBX, however, had consistently the highest percent yield increases. These results suggest that not all fungicides that reduced FLS severity equally protected yield, indicating that yield and environmental conditions need to be considered when making appropriate fungicide recommendations in tilled and no-till systems.

Mycotoxins are toxic secondary metabolites commonly found in corn and known to cause health issues to human and animals. Information on the relationship between corn grain inoculated with mycotoxins and grain nutrients (protein, oil, fatty acids, sugars, and amino acids) in corn hybrids, especially stacked-gene hybrids is very limited. The objective of this study was to investigate the nutritional advantage of stacked-gene hybrids (Stgene) over non-genetically modified organisms (non-GMO) corn or glyphosate-resistant corn (RR). The experiment was conducted in two locations (clay and sandy soils) in 2011, irrigated, and inoculated with toxigenic Aspergillus flavus using four hybrids of stacked-gene, four of RR, and two non-GMO (conventional). Non-inoculated plots were used as control. The results showed that stacked-gene hybrids had no observable nutritional advantage over RR or non-GMO as all hybrid classes accumulated adequate nutrients in their grains; this effect could be due to adequate concentrations of nutrients in the soil. Higher levels of grain protein, carbohydrates (glucose, reducing sugars, and starch), oleic acid, total amino acids, and some minerals were observed under inoculated conditions in clay and sandy soils indicated a possible osmotic adjustment role of these compounds as stress indicators and osmoprotectants under inoculated conditions. Grain nutrients in clay soil were higher than those in sandy soils; nutrient differences could be due to sandy soil possibly suffering drier conditions, especially inoculated soil, reducing nutrient uptake and nutrients mobility to the grain. This study provides advanced knowledge on the relationship between grain nutrients and mycotoxins in corn hybrids. It is also useful to the corn breeders to understand the responses of grain nutrients to fungal diseases in corn hybrids.

The seed nutrition of crops is affected by global climate changes due to elevated CO2 and temperatures. Information on the effects of elevated CO2 and temperature on seed nutrition is very limited in spite of its importance in seed quality and food security. Therefore, the objective of this study was to evaluate the effects of elevated atmospheric CO2 and temperature on seed composition (protein, oil, fatty acids, and sugars) and mineral nutrition in two soybean cultivars under controlled environments. The treatments were ambient CO2 concentrations (360 μmol mol-1) and elevated CO2 concentration (700 μmol mol-1) as well as normal temperature (26/16°C) and elevated temperature (45/35°C). Plants were grown under greenhouse conditions until the R5 stage, and then, transferred to growth chambers until full maturity (R8). Elevated temperature or a combination of elevated temperature and elevated CO2 resulted in a decrease in seed protein and linolenic acid concentrations and an increase in oil and oleic acid in cultivars Williams 82 (MGIII) and Hutcheson (MG V). Seed sucrose, glucose, and fructose decreased, whereas raffinose and stachyose remained relatively stable. Minerals also decreased under elevated CO2 and temperature. Among those that decreased were N, P, K, Zn, Fe, and B. Natural abundance of 15N and 13C isotopes was altered only under high temperature, regardless of CO2 concentration, indicating that changes in nitrogen and carbon metabolism occurred at elevated temperature. The increase in oil and oleic acid and decrease in linolenic acid are desirable, as high oleic acid and low linolenic acid contribute to the stability and longer shelf-life of oil. The combination of low protein and high oil was due to the inverse relationship between them. This study showed that seed composition and seed mineral nutrients can be affected by elevated temperature alone or elevated CO2 and temperature. This information is beneficial for selecting varieties with high seed nutritional qualities and efficient mineral nutrient use and uptake, traits that are related to seed production, seed quality, and food security. Also, it provides further knowledge on the effect of climate change on seed quality.

Genetic mapping of quantitative trait loci (QTL) associated with seed nutrition levels is almost non-existent. The objective of this study was to identify QTLs associated with seed micronutrients (iron, Fe; zinc, Zn; bororn, B; manganese, Mn; and copper, Cu) accumulation (concentration) in a population of 92 F5:7 recombinant inbred lines (RILs) that derived from a cross between MD 96-5722 (MD) and ‘Spencer’. For this purpose, a genetic linkage map based on 5,376 Single Nucleotide Polymorphism (SNP) markers was constructed using the Illumina Infinium SoySNP6K BeadChip array. The RILs were genotyped using 537 polymorphic, reliably segregating SNP markers. A total of 23 QTLs for micronutrients Fe, Zn, B, Mn, and Cu have been identified and mapped on eight linkage groups (LGs) of the soybean genome. Five QTLs were detected for Fe (qIRO001- qIRO005) on LGs N, A1, K, J, and G. Seven QTLs for Zn (qZIN001-qZIN007) on LGs D1a (Chr 1), N (Chr 3), F (Chr 5), B2 (Chr 14), J (Chr 16), A1 (Chr 5), and K (Chr 9). Two QTLs for B (qBOR001 and qBOR002) were detected on LGs N and A1. Four QTLs were detected for Mn (qMAN001-qMAN004) on LGs N, A1, K, and J, and five QTLs were detected for Cu (qCOP001- qCOP005) on LGs N, A1, K, J, and G). It was observed that the four QTLs for Zn, Cu, Fe, and Mn on LGs N (Chr 3), LG A1 (Chr 5), and LG J (Chr 16) were clustered in a similar region of the linkage groups, suggesting possible shared physiological and genetic mechanisms. The QTLs detected in this study are novel and will contribute to our understanding of the genetic basis of seed mineral nutrition. This research would allow breeders to efficiently select for higher seed nutritional qualities to meet the seed industry and human and livestock nutritional needs.

Frogeye leaf spot (FLS) of soybean, caused by Cercospora sojina, has been a problem in the southern United States for many years and has recently become a greater problem in the northern United States. Cultivars resistant to FLS have been developed for planting in the southern United States and resistance in many of these cultivars is conditioned by the Rcs3 gene. This gene conditions immunity to all known races and isolates of the pathogen. Resistance to C. sojina in soybean genotypes (cultivars and breeding lines) adapted to north-central U.S. production region is unknown. The objectives of this study were to (i) identify maturity group (MG) III, IV, and V soybean genotypes resistant to C. sojina race 11 by field screening at multiple locations over years and (ii) determine whether FLS resistance in these genotypes is likely to be conditioned by the Rcs3 gene. In total, 1,350 genotypes were evaluated for resistance to race 11 in field trials, and 13 MG III, 45 MG IV, and 15 MG V genotypes did not develop symptoms of FLS. Of these, 54 were subsequently tested for the possible presence of Rcs3 using five molecular markers located within 2 centimorgans (cM) of the gene. None of the MG III genotypes tested had the Rcs3 haplotype of cv. Davis, the source of Rcs3; six of the MG IV genotypes and seven of the MG V genotypes had the Rcs3 haplotype. This is the first report of the presence of the Rcs3 haplotype in LN 97-15076 and S99-2281. The soybean genotypes predicted to have the Rcs3 gene and other genotypes with no FLS symptoms in field trials may be useful in developing soybean cultivars with broad resistance to FLS and adapted to the northern United States.

Phomopsis longicolla is a major seed pathogen of soybean (Glycine max) in hot, humid environments. The objective of this study was to monitor the infection and development of P. longicolla on vegetative and reproductive tissues of six cultivars and to determine the relationship between this infection and subsequent seed infection and seed germination. Cultivars were grown for 3 years (2002 to 2004) without irrigation or with irrigation applied at pre- plus postflowering or at postflowering growth stages. P. longicolla was isolated most frequently from leaf, stem, pod, root, and seed. Diaporthe phaseolorum and three unidentified Phomopsis sp. were also isolated. Diaporthe aspalathi, which previously has not been reported on soybean, was also recovered from leaf samples. These isolates, however, were recovered very infrequently. Recovery of P. longicolla from roots was much lower than from leaves, stems, and pods in all years and irrigation environments. The recovery of P. longicolla from seed was affected by irrigation environments. Seed from irrigated plots had more P. longicolla than that from nonirrigated plots. Isolation of P. longicolla from seed was negatively correlated with percentage of seed germination in irrigated environments but not in the nonirrigated environment. Pod infection was correlated with seed infection in all three irrigation environments. Even though infection of leaves and stems increased with increasing moisture availability, such infection did not consistently correlate with seed infection. Seed germination and seed infection were negatively correlated with percent hard seed. This study provided the first demonstration of the seasonal progression of P. longicolla on soybean cultivars grown under three irrigation environments.

Mengistu, A., Smith, J. R., Ray, J. D., and Bellaloui, N. 2011. Seasonal progress of charcoal rot and its impact on soybean productivity. Plant Dis. 95:1159-1166. The seasonal progress of charcoal rot (caused by Macrophomina phaseolina) was measured over two growing seasons in four separate experiments: irrigated infested, irrigated non-infested, non-irrigated infested, and non-irrigated noninfested. Disease was assessed at V5, R1, R3, R5, R6, and R7 growth stages based on colony forming units (CFU) of M. phaseolina recovered from the lower stem and root tissues and the area under the disease progress curve (AUDPC). The population density of M. phaseolina increased slowly from the V5 to R6 growth stages and then rapidly from the R6 to R7 growth stages for all genotypes in all four experiments. Yield loss due to charcoal rot ranged from 6 to 33% in irrigated environments. The extent of yield loss was affected by severity of charcoal rot, which in turn was affected by year. Yield loss due to charcoal rot was consistently measured in all paired comparisons in irrigated environments, suggesting that charcoal rot can be an important disease in irrigated environments. Disease severity based on CFU accounted for more yield loss variation (42%) than did the AUDPC (36%) when used to assess disease. Growth stage R7 was found to be the optimum stage for assessing disease using CFU. In addition, screening soybean genotypes under irrigation environment may have utility in breeding programs where there is a need for evaluating soybean genotypes for both disease resistance and yield. Charcoal rot of soybean (Glycine max (L.) Merr.), caused by Macrophomina phaseolina (Tassi) Goid., is a disease of economic

Charcoal rot of soybean [Glycine max (L.) Merr.] caused by Macrophomina phaseolina is a disease of economic significance throughout the world. The effects of potassium (K) and phosphorus (P) fertilizer on disease development are unknown. Therefore, two separate trials were conducted in the field during 2008, 2009 and 2010 at Jackson and Milan, TN, USA to evaluate the effects of K and P on severity of charcoal rot. Rates of K (0, 45, 90, 134 and 179 kg K2O ha−1) and P (0, 22, 45, 67 and 90 kg P2O5 ha−1) were used, with a sixth rate ranging from 0–22 for P and 0–37 for K equal to the recommended K or P fertilizer application based on annual soil testing. The colony forming units of M. phaseolina in soil indicated no significant response for any P treatments in five of six location-by-year and for K applications in all six location-by-year environments. Similarly, no significant response in tissue CFU for all P and K treatments in all six location-by-year environments was observed, indicating that th...

Information is limited about phosphorus (P) fertilization effects on soybean seed composition. A field experiment was conducted to investigate the effects of P application rates on the concentrations of various fatty acids, protein, and oil in soybean under no-tillage on low and high testing P soils at Jackson and Milan, Tennessee from 2008 through 2011. Five P rates 0, 10, 20, 30, and 40 kg·P·ha-1 plus the recommended P fertilizer rate based on soil P testing results were arranged in a randomized complete block design with four replicates. Protein, oil, and fatty acid concentrations in seed responded differently to P fertilization. In general, protein concentrations were enhanced but oil levels decreased with increased P application rate. Palmitic and oleic concentrations responded positively to P application rate up to a certain level. However, the response of linolenic acid concentration was inconsistent (negative or positive). Stearic concentration was not influenced by P fertilization. Application of 10 kg·P·ha-1 resulted in higher production of protein and palmitic, oleic, and linolenic acids than zero P and the higher P application rates as well on the P deficient soil. Excessive P application rates could lower seed yield and the quality of some attributes in seed. In conclusion, linoleic acid concentration, a key quality attribute in soybean seed for human and animal consumption, can sometimes be enhanced by P fertilization; the indigenous soil P level and P application rate should be taken into account in breeding soybean cultivars with low linolenic acid level.

2253 Yield and �uality responses to soybean planting date have been extensively evaluated for more than a century in Tennessee (Mooers, 1908; Cartter and Hartwig, 1963). Planting date is one of the most important and least expensive production decisions aff ecting soybean seed yields and quality, so it still receives considerable attention from soybean researchers in the southern United States (Egli and Cornelius, 2009; Hu and Wiatrak, 2012). Farmers in the upper mid-southern region have become increasingly interested in the early soybean production system where short-season maturity soybean is planted early to avoid frequent midor late-season droughts and to take advantage of abundant soil moisture available earlier in the growing season (Walker et al., 2010). Th is system may be particularly suitable for the rolling uplands of Kentucky, Tennessee, eastern Mississippi, and northern Alabama, where fi eld sizes are relatively small and irrigation is less feasible (Walker et al., 2010). Th us, several related factors such as location, year-to-year climate conditions, and maturity group (MG) selection make decisions regarding the optimum planting date for soybean complex (Egli and Cornelius, 2009; Hu and Wiatrak, 2012). Egli and Cornelius (2009) used data from 28 experiments located across the United States to analyze regional weather and soil type impacts on yield-maximizing planting dates. Th ey reviewed soybean planting date studies undertaken in the Midwest (Iowa, Illinois, Indiana, North Dakota, Nebraska, and Ohio), Upper South (Arkansas, Kentucky, Missouri, and Tennessee), and Deep South (Alabama, Florida, Georgia, Louisiana, Mississippi, and South Carolina) and found that yield potential decreased when soybean was planted aft er late May in the Midwest and Deep South and aft er early June in the Upper South. Yields decreased at a faster rate in the Deep South and Upper South than in the Midwest aft er the optimal planting date, primarily because of decreased vegetative and reproductive growth that reduced the number of branches and pods, decreased plant height, and reduced photosynthesis (Popp et al., 2002; Pedersen and Lauer, 2003; Bastidas et al., 2008; De Bruin and Pedersen, 2008). Photoperiod, temperature, and precipitation were the primary factors responsible for reduced yield Crop economics, Production & Management

Interest in using harvest aids (defoliants or crop desiccants) such as paraquat, carfentrazone-ethyl, glyphosate, and sodium chlorate (NaClO3) have become increasingly important to assure harvest efficiency, producer profit, and to maintain seed quality. However, information on the effects of harvest aids on seed nutrition (composition) (protein, oil, fatty acids, sugars, and amino acids) in soybean is very limited. The objective of this research was to investigate the influence of harvest aids on seed protein, oil, fatty acids, sugars, and amino acids in soybean. Our hypothesis was that harvest aid may influence seed nutrition, especially at R6 as at R6 the seeds may still undergo biochemical changes. Field experiments were conducted in 2012 and 2013 under Midsouth USA environmental conditions in which harvest aids were applied at R6 (seed-fill) and R7 (yellow pods) growth stages. Harvest aids applied included an untreated control, 0.28 kg ai ha&minus, 1 of paraquat, 0.28 kg ai ha&minus, 1 of paraquat, and 1.015 kg ai ha&minus, 1 of carfentrazone-ethyl (AIM), 6.72 kg ai ha&minus, 1 sodium chlorate, 1.015 kg ai ha&minus, 1 carfentrazone-ethyl, and 2.0 kg ae ha&minus, 1 glyphosate. Results showed that the application of harvest aids at either R6 or R7 resulted in the alteration of some seed composition such as protein, oil, oleic acid, fructose, and little effects on amino acids. In addition, harvest aids affected seed composition constituents differently depending on year and growth stage. This research demonstrated the possible alteration of some nutrients by harvest aids. This research helps growers and scientists to advance the understanding and management of harvest aids and investigate possible effects of harvest aids on seed nutrition.

NPK fertilizer briquettes (NPKBriq) and organically enhanced N fertilizer (OENF), as newly developed fertilizer products, are reported to increase maize (Zea mays L.) yield and N use efficiency, but their effects on maize grain composition are unknown. The objective of this study was to determine the effects of NPKBriq and OENF on the protein, oil, fiber, ash, and starch of maize grain. A field study was conducted at Jackson and Grand Junction, TN, during 2012 and 2013, with NPKBriq, OENF, ammonium sulfate ((NH4)2SO4) (+P and K), and urea (+P and K) as the main treatments and 0, 85, 128, and 170 kg N ha&minus, 1 as the sub treatments under a randomized complete block split plot design with four replicates. The fiber concentration was more responsive to the fertilizer source than the protein, oil, ash, and starch concentrations. OENF resulted in a higher fiber concentration than NPKBriq at 85 kg N ha&minus, 1 in 2013, averaged over the two sites. Both OENF and NPKBriq had nearly no significant effects on the concentrations of the quality attributes compared with ammonium sulfate and urea. In conclusion, the nutrient-balanced NPKBriq exerts the same or greater effects on maize grain quality relative to the commonly used nutrient management practices of urea (+P and K) and ammonium sulfate (+P and K) under normal weather conditions. OENF is an alternate N source to urea and ammonium sulfate for similar to higher maize grain quality.

This study examines the influence of livestock holding on households’ decision to participation in wood fuel production from dryland forest. Survey data were collected from 160 households in Dire Dawa administration council of Oromia state, Ethiopia following a snowball sampling technique. Binary logit regression model and descriptive statistics were used to analyze the impacts of livestock holding on households’ decision to participation in fuelwood production from dryland forest. The estimation of the model indicates that livestock and size of arable land holdings were significant factors in determining households’ participation in wood fuel production. An increase of one unit in livestock holding leads to the probability of participation in wood fuel production of households decreased by 0.118 units while the land size has a negative impact on the participation of wood fuel production. When land size increased by 1 hectare the probability of participating in wood fuel production will be decreased by 0.9 units. The mean of wood fuel producers’ livestock holding was about 5.84 TLU and 10.67 for non- wood fuel producer which indicates the negative correlation of livestock holding and wood fuel production. Thus the study concludes that households with large livestock less likely to participate in wood fuel extraction from dryland forest. Promoting sustainable livestock production with appropriate grazing plan can have a significant role in dryland forest conservation and sustainable forest management.

Mengistu, A., Kelly, H. M., Bellaloui, N., Arelli, P. R., Reddy, K. N., and Wrather, A. J. 2014. Tillage, fungicide, and cultivar effects on frogeye leaf spot severity and yield in soybean. Plant Dis. 98:1476-1484. Frogeye leaf spot (FLS) of soybean, caused by Cercospora sojina, has been a problem in the southern United States for many years but has become an increasing problem in the northern United States more recently, causing significant yield losses. This increase in disease severity in the northern United States has been attributed to increased utilization of no-till planting and changes in climate. A field study was conducted at the University of Tennessee, Research and Education Center in Milan, TN from 2007 to 2010 to determine severity in tilled and no-till plots treated with or without fungicide at R3 and R5 growth stages. Three FLS-susceptible cultivars, one each in Maturity Groups III, IV, and V, were treated with pyraclostrobin (Headline) fungicide. Analysis of variance using the area under the disease progress curve (AUDPC) indicated no significant difference (P ≤ 0.05) in disease severity between tilled and no-till plots without fungicide. Fungicide did not significantly reduce disease under no-till, but did under tilled plots. This is the first study showing that no-till plots did not reduce or enhance the severity of FLS when no fungicide was applied. Fungicide application significantly reduced (P ≤ 0.05) disease severity and AUDPC and increased yield in tilled plots. The yield gains in tilled, fungicide-treated plots ranged from 1 to 17%. When fungicide was applied, disease severity was not reduced as significantly in no-till as in treated tilled plots, suggesting that fungicide programs under a notill system may require further study to minimize the risk of FLS