Soybean (
L. Merr.) production is influenced by planting date, but its impact on yield in fields infested with
(Tassi) Goid. is unknown. A 3-year study was conducted in
-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
, early May to early June planting coupled with appropriate cultivar selection provides maximum yield potential for western Tennessee and mid-southern soybean growers.
A history of exposure to harsh physical discipline has been linked to negative outcomes for children, ranging from conduct disorder to depression and low self-esteem. The present study extends this ...work into adolescence, and examines the relationship of lifetime histories of harsh discipline to adolescents' internalizing and externalizing symptoms and to their developing capacities for establishing autonomy and relatedness in family interactions. Adolescent and parent reports of harsh discipline, independently coded observations of conflictual interactions, and adolescent reports of symptoms were obtained for 141 adolescents at age 16. Both parents' use of harsh discipline was related to greater adolescent depression and externalizing behavior, even when these effects were examined over and above the effects of other parenting measures known to account for these symptoms. Adolescents exposed to harsh discipline from mothers were also less likely to appear warm and engaged during an interaction task with their mothers. It is suggested that a history of harsh discipline is associated not only with social and emotional functioning, but also with the developmental task of autonomy and relatedness.
Soybean cyst nematode (SCN), Heterodera glycines, HG type 1.2.5.7 is the most virulent and widespread SCN biotype in the southern states of the USA, but its effect on soybean (Glycine max L. Merr.) ...nitrogen fixation (NF) activity and growth is not well documented. The objectives of this study were to: (1) measure the impact of HG type 1.2.5.7 on NF activity during the early vegetative stage of three soybean genotypes and (2) compare the impact on soybean leaf and root development, and plant growth. The NF activity of two susceptible (S) genotypes ("Ellis" and "Williams 82") and one resistant (R) genotype (PI 88,788), subjected to a 10,000-egg treatment, was measured using an in-situ flow-through acetylene reduction assay. The average NF activity of the soybean genotypes was decreased by SCN activity. Time points assessment showed that the NF activity was differently impacted among the genotypes. Based on the measured values, the NF activity was decreased by 30% in SCN infected plants of Williams 82 but that of PI 88,788 and Ellis was affected. Likewise, soybean leaf color and leaf area were affected by SCN infection, but there was no impact on root length and root area. These results showed that SCN HG type 1.2.5.7 can exhibit varying negative impact on NF and shoot growth of S soybean genotypes, while R genotypes may be unaffected. Thus, indicating genetic resistance continues to be a critical tool for the management of the SCN.
The potential of species of
Fusarium
to cause significant economic losses in
Cannabis sativa
due to plant diseases and mycotoxin residues is the subject of this review. Sixteen species of
Fusarium
, ...reported as associated with cannabis production, are classified in six species complexes:
Fusarium oxysporum, F. solani, F. incarnatum-equiseti, F. sambucinum, F. tricinctum
, and
F. fujikuroi
. Taxonomy in this genus is the subject of debate, and removal of species in the
F. solani
Species Complex to the genus,
Neocosmospor
a, has been proposed. Many species associated with
C. sativa
are also opportunistic pathogens of humans and animals. Species of
Fusarium
produce a myriad of mycotoxins, including at least three (deoxynivalenol, zearalenone, and fumonisin B) deemed the most important mycotoxins in human and animal foods. These chemicals vary from the very simple chemicals (moniliformin and butanolide) to the structurally complex depsipeptides (beauvericin and enniatin B) and trichothecenes (deoxynivalenol and its acetylated derivatives, diacetoxyscirpenol, and T-2-toxin). The robust strategies for disease management (e.g., exclusion of the pathogen, control of environment, and host resistance) are in development for this new crop and have primarily relied on management systems for other crops. Biopesticides have been labeled for use on
C. sativa
; however, few efficacy trials have been performed. Host resistance to these pathogens and transmission are also understudied. The new markets for
C
.
sativa
and its derivative products require knowledge for control of these important fungal diseases to provide safe products for human consumption.
Brown spot, caused by
, is a common foliar disease of soybean (
). Applications of fungicide products that contain quinone outside inhibitor (QoI) active ingredients to soybean fields have ...contributed to the selection and development of QoI-resistant populations of
. We investigated the molecular mechanisms of QoI-resistance in these populations through targeted analysis of the cytochrome
gene. Isolates of
collected from several soybean fields over different seasons varied in sensitivity to QoI fungicides. Characterization of the cytochrome
gene revealed a mutation that changed an amino acid from glycine to alanine at codon 143 - one that is generally associated with QoI fungicide resistances. A PCR assay was developed that allowed successful discrimination of QoI-sensitive and -resistant isolates based on the G143A mutation. Results of this study demonstrated that 47.5% of
isolates tested were resistant to QoI fungicides. Accurate monitoring of this mutation will help slow the spread of QoI resistance and will be important for fungicide resistant management in this pathosystem.
The pathogen causing soybean rust, Phakopsora pachyrhizi, was first described in Japan in 1902. The disease was important in the Eastern Hemisphere for many decades before the fungus was reported in ...Hawaii in 1994, which was followed by reports from countries in Africa and South America. In 2004, P. pachyrhizi was confirmed in Louisiana, making it the first report in the continental United States. Based on yield losses from countries in Asia, Africa, and South America, it was clear that this pathogen could have a major economic impact on the yield of 30 million ha of soybean in the United States. The response by agencies within the United States Department of Agriculture, industry, soybean check-off boards, and universities was immediate and complex. The impacts of some of these activities are detailed in this review. The net result has been that the once dreaded disease, which caused substantial losses in other parts of the world, is now better understood and effectively managed in the United States. The disease continues to be monitored yearly for changes in spatial and temporal distribution so that soybean growers can continue to benefit by knowing where soybean rust is occurring during the growing season.
Consistent with social identity theory, political identity was strongly linked to conservative Christians’ morality represented by the Moral Foundation Theory model. Participants identifying as ...Democrats scored significantly higher than did those identifying as Republicans on the individualizing foundations of care and fairness but significantly lower than Republicans on the binding foundations of authority, loyalty, and purity. In addition, political identity differentially related to the two liberty subfoundations consistent with salient political party themes. Hierarchical regression analyses identified political identity as a consistent predictor of all moral foundations beyond the variance accounted for by unique contributions of gender and education. RS factors, primarily fundamentalism, contributed additional incremental value to predicting the three binding but not the individualizing foundations, which suggests a congruent dual identity (political, religious) for Republicans that does not hold for Democrats.
Diaporthe seed decay can compromise seed quality in soybean
(L.) Merr. in the warm and humid production areas of the United States during crop maturation. In the current study, 45 isolates of
were ...recovered from seed sampled from soybean fields affected by
-associated diseases in eight U.S. states in 2017. The isolates obtained belonged to 10 species of
based on morphology and phylogenetic analyses of the internal transcribed spacer, partial translation elongation factor 1-α, and β-tubulin gene sequences. The associated species included
,
,
,
,
,
,
, and three novel fungi,
,
, and
. One isolate each of the 10 species was examined for pathogenicity on seed of cultivar Sava under controlled conditions. Seven days postinoculation, significant differences in the percentages of decayed seeds and seedling necrosis were observed among the isolates and the noninoculated control (
< 0.0001). While the isolates of
,
, and
caused a significantly greater percentage of decayed seeds (
< 0.0001), the isolate of
caused the greatest seedling necrosis (
< 0.0001). The observation of new fungi causing Diaporthe seed decay suggests the need for a more comprehensive survey in U.S. soybean producing areas since members of the genus
appear to form a complex that causes seed decay.
Foliar fungicide applications to corn (Zea mays L.) occur at one or more application timings ranging from early vegetative growth stages to mid-reproductive stages. Previous studies indicated that ...fungicide applications are profitable under high disease pressure when applied during the tasseling to silking growth stages. Few comprehensive studies in corn have examined the impact of fungicide applications at an early vegetative growth stage (V6) compared to late application timings (VT) for yield response and return on fungicide investment (ROI) across multiple locations.
Compare yield response of fungicide application timing across multiple fungicide classes and calculate the probability of positive ROI.
Data were collected specifically for this analysis using a uniform protocol conducted in 13 states in the United States and one province in Canada from 2014-2015. Data were subjected to a primary mixed-model analysis of variance. Subsequent univariate meta-analyses, with and without moderator variables, were performed using standard meta-analytic procedures. Follow-up power and prediction analyses were performed to aid interpretation and development of management recommendations.
Fungicide application resulted in a range of yield responses from -2,683.0 to 3,230.9 kg/ha relative to the non-treated control, with 68.2% of these responses being positive. Evidence suggests that all three moderator variables tested (application timing, fungicide class, and disease base level), had some effect (α = 0.05) on the absolute difference in yield between fungicide treated and non-treated plots (Formula: see text). Application timing influenced Formula: see text, with V6 + VT and the VT application timings resulting in greater yield responses than the V6 application timing alone. Fungicide formulations that combined demethylation inhibitor and quinone outside inhibitor fungicides significantly increased yield response.
Foliar fungicide applications can increase corn grain yield. To ensure the likelihood of a positive ROI, farmers should focus on applications at VT and use fungicides that include a mix of demethylation inhibitor and quinone outside inhibitor active ingredients.
Frogeye leaf spot (FLS), caused by
, is an important foliar disease affecting soybean in the United States. A meta-analytic approach including 39 fungicide trials conducted from 2012 to 2021 across ...eight states (Alabama, Arkansas, Illinois, Iowa, Kentucky, Louisiana, Mississippi, Tennessee) was used to assess the relationship between FLS severity and soybean yield. Correlation and regression analyses were performed separately to determine Fisher's transformation of correlation coefficients (Z
), intercept (β
) and slope (β
). Disease pressure (low severity, ≤34.5; high severity, >34.5%) and yield class (low, ≤3,352; high, >3,352 kg/ha) were included as categorical moderators. Pearson's Formula: see text, obtained from back-transforming the Formula: see text
estimated by an overall random-effects model, showed a significant negative linear relationship between FLS severity and yield (Formula: see text = -0.60). The Formula: see text
was affected by disease pressure (
= 0.0003) but not by yield class (
= 0.8141). A random-coefficient model estimated a slope of -19 kg/ha for each percent severity for a mean attainable yield of 3,719.9 kg/ha. Based on the overall mean (95% CI) of the intercept and slope estimated by the random-coefficients model, the estimated overall relative damage coefficient was 0.51% (0.36 to 0.69), indicating that a percent increase in FLS severity reduced yield by 0.51%. The best model included yield class as a covariate, and population-average intercepts differed significantly between low (3,455.1 kg/ha) and high (3,842.7 kg/ha) yield classes. This highlights the potential impact of FLS on soybean yield if not managed and may help in disease management decisions.
PDF
