Corn Pollen Research Articles

Development of a landscape in NE Minnesota, from the Early Holocene to Forest-harvesting, Agriculture and Industry

An array of lake sediment proxies including paleobotanic, geochemical, and historical records has been used to determine former environments of Bugbee Pond, a small, mesotrophic pond in northeastern Minnesota. Much research has been produced on the history of climate and vegetation change of the region, yet we have little information on the impact of human settlement. This well-dated, high resolution, multi-proxy record is important for its length and concentration on the historic period. The lake itself became established by ~7000 years ago. Pollen evidence suggests a transition between the regional Prairie Period to the Great Lakes mixed conifer – hardwood forest was established in the region at this time. XRF data suggest dry basin accumulation early in the record after ~7000 cal yr BP, but lake levels substantially increased by ~5600 cal yr BP, during a regionwide climatic transition to more humid conditions. Birch and boreal conifers increased after about 3800 cal yr BP; further increases in boreal conifers occurred by ~2000 cal yr BP. Anthropogenic vegetation changes during the Historic period, beginning in the late 19th century, is well represented by forest clearance of white pine ( Pinus strobus), followed by increases in early successional species and an increased sediment accumulation rate due to land clearance. Establishment of farming communities locally are shown by occurrence of corn ( Zea mays) and oat ( Avena sativa) pollen, and pasturing and grazing are documented by Rumex, Fabaceae and Poaceae pollen, as well as coprophilous fungi, such as Sordaria. The increase and subsequent decline in Pb and S concentrations in the uppermost sediments are mirrored by historically documented, nearby industrial activities.

Maize pollen carry bacteria that suppress a fungal pathogen that enters through the male gamete fertilization route.

In flowering plants, after being released from pollen grains, the male gametes use the style channel to migrate towards the ovary where they fertilize awaiting eggs. Environmental pathogens exploit the style passage, resulting in diseased progeny seed. The belief is that pollen also transmits pathogens into the style. By contrast, we hypothesized that pollen carries beneficial microbes that suppress environmental pathogens on the style passage. No prior studies have reported pollen-associated bacterial functions in any plant species. Here, bacteria were cultured from maize (corn) pollen encompassing wild ancestors and farmer-selected landraces from across the Americas, grown in a common field in Canada for one season. In total, 298 bacterial isolates were cultured, spanning 45 genera, 103 species, and 88 OTUs, dominated by Pantoea, Bacillus, Pseudomonas, Erwinia, and Microbacterium. Full-length 16S DNA-based taxonomic profiling showed that 78% of bacterial taxa from the major wild ancestor of maize (Parviglumis teosinte) were present in at least one cultivated landrace. The species names of the bacterial isolates were used to search the pathogen literature systematically; this preliminary evidence predicted that the vast majority of the pollen-associated bacteria analyzed are not maize pathogens. The pollen-associated bacteria were tested in vitro against a style-invading Fusarium pathogen shown to cause Gibberella ear rot (GER): 14 isolates inhibited this pathogen. Genome mining showed that all the anti-Fusarium bacterial species encode phzF, associated with biosynthesis of the natural fungicide, phenazine. To mimic the male gamete migration route, three pollen-associated bacterial strains were sprayed onto styles (silks), followed by Fusarium inoculation; these bacteria reduced GER symptoms and mycotoxin accumulation in progeny seed. Confocal microscopy was used to search for direct evidence that pollen-associated bacteria can defend living silks against Fusarium graminearum (Fg); bacterial strain AS541 (Kluyvera intermedia), isolated from pollen of ancestral Parviglumis, was observed to colonize the susceptible style/silk entry points of Fg (silk epidermis, trichomes, wounds). Furthermore, on style/silk tissue, AS541 colonized/aggregated on Fg hyphae, and was associated with Fg hyphal breaks. These results suggest that pollen has the potential to carry bacteria that can defend the style/silk passage against an environmental pathogen - a novel observation.

Functional immune boosters; the herb or its dead microbiome? Antigenic TLR4 agonist MAMPs found in 65 medicinal roots and algae's.

Humans have been consuming medicinal plants (as herbs/ spices) to combat illness for centuries while ascribing beneficial effects predominantly to the plant/phytochemical constituents, without recognizing the power of obligatory resident microorganism' communities (MOCs) (live/dead bacteria, fungus, yeast, molds etc.) which remain after industrial microbial reduction methods. Very little is known about the taxonomic identity of residual antigenic microbial associated molecular patterns (MAMPs) debris in our botanical over the counter (OTC) products, which if present would be recognized as foreign (non-self) antigenic matter by host pattern recognition receptors (PRRs) provoking a host immune response; this the basis of vaccine adjuvants. As of today, only few research groups have removed the herbal MAMP biomass from herbs, all suggesting that immune activation may not be from the plant but rather its microbial biomass; a hypothesis we corroborate. The purpose of this work was to conduct a high through put screening (HTPS) of over 2500 natural plants, OTC botanical supplements and phytochemicals to elucidate those with pro-inflammatory; toll like receptor 4 (TLR4) activating properties in macrophages. The HTPS was conducted on RAW 264.7 cells vs. lipopolysaccharide (LPS) E. coli 0111:B4, testing iNOS / nitric oxide production as a perimeter endpoint. The data show not a single drug/chemical/ phytochemical and approximately 98 % of botanicals to be immune idle (not effective) with only 65 pro-inflammatory (hits) in a potency range of LPS. Method validation studies eliminated the possibility of false artifact or contamination, and results were cross verified through multiple vendors/ manufacturers/lot numbers by botanical species. Lead botanicals were evaluated for plant concentration of LPS, 1,3:1,6-β-glucan, 1,3:1,4-β-D-glucan and α-glucans; where the former paralleled strength in vitro. LPS was then removed from plants using high-capacity endotoxin poly lysine columns, where bioactivity of LPS null "plant" extracts were lost. The stability of E.Coli 0111:B4 in an acid stomach mimetic model was confirmed. Last, we conducted a reverse culture on aerobic plate counts (APCs) from select hits, with subsequent isolation of gram-negative bacteria (MacConkey agar). Cultures were 1) heat destroyed (retested/ confirming bioactivity) and 2) subject to taxonomical identification by genetic sequencing 18S, ITS1, 5.8 s, ITS2 28S, and 16S. The data show significant gram negative MAMP biomass dominance in A) roots (e.g. echinacea, yucca, burdock, stinging nettle, sarsaparilla, hydrangea, poke, madder, calamus, rhaponticum, pleurisy, aconite etc.) and B) oceanic plants / algae's (e.g. bladderwrack, chlorella, spirulina, kelp, and "OTC Seamoss-blends" (irish moss, bladderwrack, burdock root etc), as well as other random herbs (eg. corn silk, cleavers, watercress, cardamom seed, tribulus, duckweed, puffball, hordeum and pollen). The results show a dominance of gram negative microbes (e.g. Klebsilla aerogenes, Pantoae agglomerans, Cronobacter sakazakii), fungus (Glomeracaea, Ascomycota, Irpex lacteus, Aureobasidium pullulans, Fibroporia albicans, Chlorociboria clavula, Aspergillus_sp JUC-2), with black walnut hull, echinacea and burdock root also containing gram positive microbial strains (Fontibacillus, Paenibacillus, Enterococcus gallinarum, Bromate-reducing bacterium B6 and various strains of Clostridium). This work brings attention to the existence of a functional immune bioactive herbal microbiome, independent from the plant. There is need to further this avenue of research, which should be carried out with consideration as to both positive or negative consequences arising from daily consumption of botanicals highly laden with bioactive MAMPS.

Plant pollen as a resource affecting the development and survival of the mosquitoes Anopheles quadrimaculatus and Culex quinquefasciatus (Diptera: Culicidae).

Mosquito larvae often subsist on inputs of terrestrial-derived resources, including leaves and dead insects. However, seasonal inputs of plant pollen is an underexplored resource for many species. We compared the effects of three levels (low, medium, high) of two pollen types (corn, pine) on development, mass, and survival in Anopheles quadrimaculatus (Say) and Culex quinquefasciatus (Say) (Diptera: Culcidae). We also examined the nutrient content of adults (%nitrogen, %carbon, C:N) and stable isotopes (δ15N, δ13C). Culex quinquefasciatus had the highest survival rates when grown on high and medium pine pollen compared with low pine. Survival of Culex quinquefasciatus was generally higher compared to that of An. quadrimaculatus on any level of pine, with the latter species having higher survival in high corn. Nutrient content for An. quadrimaculatus did not vary significantly in either pollen type or amount but were more enriched in δ15N in corn pollen relative to pine pollen. For Cx. quinquefasciatus, %N decreased and C:N ratio increased across low to high amounts of corn. Adults raised in corn had generally more δ13C compared to pine pollen. No developmental differences across diets were observed for either species, however both sexes of Cx. quinquefasciatus were generally larger when grown in high pine and medium and high corn pollen compared with other treatments. The poor performance of An. quadrimaculatus on corn pollen was unexpected, however, we show a benefit of corn pollen to Cx. quinquefasciatus with implications for West Nile virus transmission in the United States, especially around agricultural areas where corn is grown.

Physicochemical, antioxidant, antimicrobial, and in vitro cytotoxic activities of corn pollen protein hydrolysates obtained by different peptidases.

The applications of protein hydrolysates as food preservatives and nutraceutical ingredients have attracted much attention because of their beneficial effects. The interest in these ingredients has shifted toward their biological activities with benefits to human health. Bioactive peptides are known as antioxidant agents that could promote health-promoting effects and prolong food shelf-life beyond their basic nutritional value. Thus, the aim of this study was to investigate antioxidant, antimicrobial, and in vitro cytotoxic properties of corn pollen protein (CPP) hydrolysates obtained by different enzymes. Proteolytic activity in terms of degree of hydrolysis (DH) and SDS-PAGE analysis was measured in pancreatin (H-Pan), pepsin (H-Pep), and trypsin (H-Tri) hydrolysates. Amino acid composition, antioxidant and antimicrobial activities, and cytotoxicity of hydrolysates were evaluated. DH and SDS-PAGE revealed higher proteolytic activity of pepsin compared to other enzymes. Amino acid analysis showed that the functional amino acids such as antioxidant types were most predominant in H-Pep compared to two other samples. Antioxidant activity of hydrolysates was found to be affected by the type of enzyme and the concentration of hydrolysates. There was a significant difference (p < 0.05) between antioxidant activity of different hydrolysates. The highest antioxidant activity in terms of Trolox equivalent antioxidant capacity (0.23-2.75 mM), DPPH (33.3%-64.8%), and hydroxyl (33.7%-63.2%) radical scavenging activities, chelation of iron (33.2%-62.5%) and copper (30.2%-50.5%) metals, and total antioxidant activity (0.65-0.85) was obtained for H-Pep followed by H-Pan and H-Tri samples. Antibacterial tests showed that pepsin-hydrolyzed protein was not significantly (P > 0.05) effective against E.coli at any concentrations, however, it showed significant (P < 0.05) concentration-dependent effect against S.aureus (with inhibition zones of 15-25 mm). Cytotoxicity results revealed that CPP, as a nonhydrolyzed protein, did not generally show antiproliferative activity, however, a significant (P < 0.05) ability of H-Pep hydrolysate in decreasing HT-29 colon cancer cell line viability was seen in a concentration-dependent manner (the lowest cell viability of 32% at 5mg/mL). Overall, investigating the application of protein-based hydrolysates is one of the possible strategies that govern their applied intentions as preservatives and nutraceuticals in the food and pharmaceutical industries.

How omnivory affects the survival and choices of earwig Doru luteipes (Scudder) (Dermaptera: Forficulidae)?

Doru luteipes (Scudder, 1876) is an omnivorous predator that finds different food resources in the corn plant: eggs of Spodoptera frugiperda (J.E. Smith, 1797), uredospores of Puccinia polysora (Underw, 1897), and pollen. Knowing the survival and food preferences of this predator is essential to define its relevance as a biological control agent. We hypothesize that the foraging behavior and predatory capacity of D. luteipes may be affected when several food resources, especially eggs of S. frugiperda, uredospores of P. polysora, and pollen are concurrently in the same plant. The survival of D. luteipes in the nymph stage and their preference among food resources, often available in corn plants, were determined. To verify the survival of D. luteipes, newly hatched nymphs were fed exclusively with 1- uredospores of P. polysora, 2- eggs of S. frugiperda, 3- corn pollen, 4- a combination of uredospores + eggs, and 5- artificial diet (control). In another experiment, nymphs and adults of D. luteipes with 24 and 48 hours of fasting were individually released in the center of a container with four diets: 1- uredospores of P. polysora, 2- eggs of S. frugiperda, 3- corn pollen, 4- artificial diet, and maintained for 10 minutes, to evaluate the food choice and feeding time. The exclusive feeding with S. frugiperda eggs caused low nymph survival (8%), but the combination of P. polysora uredospores + S. frugiperda eggs allowed 58.3% survival. D. luteipes preferred feeding during the nighttime and the most significant proportions of choices by nymphs and adults were for pollen and diet, with adults spending more time eating pollen. These findings indicate that the trophic choices of D. luteipes are relevant to understand its contribution as an agent to control pest insects and fungal diseases in corn.

The maize Ga1-s allele confers protection against ga1 pollen in popcorn and dent corn

Because corn pollen can be carried great distances by wind, maintaining genetic purity of corn grain is challenging. The challenge is substantially reduced in popcorn, which carries the Ga1-s allele preventing pollination by ga1 plants, which include the vast majority of non-popcorn commercial maize varieties in the U.S.. Ga1-s can be transferred into dent corn but the effectiveness of the Ga1-s allele in popcorn and dent corn has never been compared, which is important because each are regulated differently regarding GMO contamination. We compared pollen exclusion of commercial popcorn hybrids, Ga1-s dent corn hybrids and normal dent corn hybrids for their ability to exclude ga1 pollen using a sensitive field-based assay. While both popcorn and Ga1-s dent corn had significantly better pollen exclusion than normal dent corn, popcorn was significantly better than Ga1-s dent corn on average. Some Ga1-s dent hybrids excluded as well or better than some popcorn lines suggesting that identification of hybrids comparable to popcorn is possible. The information in this study will support revised gene purity regulations potentially decreasing costs and increasing genetic purity of organic corn.

Crushing corn pollen grains increased diet digestibility and hemolymph protein content while decreasing honey bee consumption

Crushing corn pollen grains increased diet digestibility and hemolymph protein content while decreasing honey bee consumption

High maize barrier prevents maize pollen transfer in mixed crops

BACKGROUND: There is no scientifically-based assessment for the safety during co-cultivation of genetically modified and ordinary maize plants in Russia. The influence of the barrier from high maize plants for pollen-mediated gene flow in the 2020 field experiment (South-East of the European part of Russia, Saratov region) was evaluated.&#x0D; MATERIALS AND METHODS: We used the high (2,152,90 m) maize hybrids (Kaz LK 178 and ES Regain) as a barrier for pollen-madiated gene flow from pollen donor (Purple Saratovskaya) with purple grain to recipient (Bursting Corn) maize line with yellow grain.&#x0D; RESULTS: The analysis of the ears of the recipient maize line showed that not a single purple grain was found on them. It was found that in the presence of a barrier zone with a width of 315 m (depending on the direction), crossing in recipient maize line in all directions from the donor is completely excluded.&#x0D; CONCLUSIONS: It was established, for the first time, that the barrier from high maize hybrid plants completely excludes over-pollination between donor and Bursting Corn, recipient maize plants with different flowering time. In the study of barrier plants as pollen recipients, it was found that the percentage of crosses on the cob of barrier plants ranged from 0.1 to 7.1%. The number of crosses exceeding 0.9% is observed mainly in the ES Regain variety at close (15 m) distances from the donor, regardless of the prevailing wind direction. Based on the results of model experiments, it can be recommended to use a barrier for corn pollen from tall maize plants and maize varieties with different flowering periods to exclude uncontrolled over-pollination of maize varieties in the South-East of the European part of Russia conditions.

Pollen Feeding Reduces Predation of Northern Corn Rootworm Eggs (Coleoptera: Chrysomelidae, Diabrotica barberi) by a Soil-Dwelling Mite (Acari: Laelapidae: Stratiolaelapsscimitus).

Simple SummaryFlowering plants are used to enhance pest control by predators and parasitoids, but insect herbivores can also use floral resources. We documented the species of adult rootworm beetles on key plants, and found that northern corn rootworm (NCR) adults were commonly associated with sunflower inflorescences while western corn rootworm adults were most abundant in corn and on squash blossoms. Consumption of sunflower and corn pollen by NCR adults did not impact predation of their eggs by an omnivorous mite, but a predatory soil-dwelling mite ate pest eggs less frequently and took longer to feed on eggs when NCR adults had fed on sunflower pollen. While increasing plant diversity can benefit natural enemies and pest control within agroecosystems, it is important to consider how floral resources alter dietary preferences of biocontrol agents.Landscape diversification with flowering plants can benefit pollinators and natural enemies, although insect pests can also use floral resources for nutrition and chemoprotection. Corn rootworms (Coleoptera: Chrysomelidae, Diabrotica spp.) are major pests of corn (Zea mays L.), and while subterranean larvae primarily feed on corn roots, adult rootworms commonly consume floral resources from other plant species. We quantified the species, density, and sex of adult corn Diabroticite rootworm beetles on wild and cultivated sunflower, corn, and squash, quantified pollen within the bodies of adult northern corn rootworms [NCR, D. barberi (Smith & Lawrence)], and investigated how consumption of sunflower and corn pollen by NCR adults impacted predation of their eggs by two soil-dwelling mites with different feeding specialization. NCR were the most common Diabroticite species on sunflower inflorescences and western corn rootworm (WCR, D. v. virgifera LeConte) were more abundant in corn and squash blossoms. Pollen feeding by NCR adults did not impact egg predation by omnivorous Tyrophagus putrescentiae (Schrank) (Acari: Sarcoptiformes, Acaridae), but predatory Stratiolaelaps scimitus (Womersley) (Acari: Mesostigmata, Laelapidae) ate eggs less frequently and took longer to feed on eggs from NCR females that had fed on sunflower pollen. This research suggests pollen feeding by adult NCR can impact predation of their eggs. While increasing plant diversity can benefit natural enemies and pest control within agroecosystems, it is important to consider how floral resources alter dietary preferences of biocontrol agents.

INTENSITY OF CESIUM-137 ACCUMULATION IN FLOWER POLLEN OF CORN AT DIFFERENT pH OF SOIL ENVIRONMENT

137Сs is concentrated in soils and is in a continuous cycle, the intensity of movement of which depends on a number of factors, in particular on the type of soil, its composition and properties, botanical origin of plants and others. . It was found that under the same ecological conditions the accumulation coefficient of 137Cs in the distribution of honey plants can differ up to 3 times. The migration of radionuclides into vegetation is lower on soils with high levels of nutrients, compared to low-nutrient soils. This feature is inherent in both agricultural and forest soils. High migr ation of radionuclides was observed on sod-podzolic sandy soils, while on chernozems it was relatively lower. Soils of honey lands in the studied areas are mainly sod-podzolic. They are characterized by a low content of humus and trace elements, sometimes with high acidity, which can increase the translocation of radionuclides in plants and their products, in particular pollen. After the half-life of 137Cs, which was released into the environment after the Chernobyl accident, there is a certain pattern of intensity of contamination of protein products of beekeeping depending on its type, harvesting period and intensity of contamination of honey lands. Along with this, it should be noted that the exceedance of permissible levels is observed only for cesium-137 in the territory of honey lands in the soil of which this element exceeded 4 Ki / km2. On the basis of the fact that pollen is the main raw material for the production of protein products of beekeeping, further research was aimed at studying measures to improve the quality of this raw material in order to reduce cesium-137 in bee pollen and persimmon. The intensity of 137Cs contamination of corn pollen was studied. It was found that lowering the soil pH from 4.6 to 7.7 contributes to a decrease in the pollen of maize pollen activity 137Cs from 9.7 Bq / kg to 5.8 Bq / kg, hazard factor from 0.049 to 0.029 and accumulation factor from 0 , 28 to 0.14.

Benefits of a balanced diet? Mixing prey with pollen is advantageous for the phytoseiid predator Amblydromalus limonicus

Plant pollen is an important alternative food for generalist phytoseiid mites ensuring survival and supporting population build-up during periods of prey scarcity. However, in the short term predator efficacy can be negatively affected by pollen provisioning as a consequence of predator satiation or when pollen is preferred over prey. This is counteracted by the fact that, combining pollen with prey in a balanced mixed diet, may benefit the numerical response of the predator and thus, improve the effectiveness of long-term biological control. Here, we assessed the effects of pollen (Typha angustifolia, Zea mays, Pinus brutia) provisioning in a mixed diet with prey (thrips) on the performance and predation efficiency of Amblydromalus limonicus, a predatory mite used against thrips and whiteflies in greenhouse crops. We found that provisioning pollen in mixed diets with high-quality prey resulted in significant decrease in prey consumption. This effect was shown to be stronger for T. angustifolia and weaker for P. brutia when both were combined with thrips larvae. When pollen was provided alongside thrips, this resulted in a significant decrease in juvenile dispersal and oviposition was always higher. The highest value of intrinsic rate of population increase (rm) was recorded for the mix of cattail pollen and thrips, and the strongest increase in rm when thrips were combined with pine pollen followed by corn and cattail pollen. Overall, mixing prey with pollen resulted in higher rm values thus enhancing the medium- to long-term thrips-control potential of A. limonicus.

Nát'oh Baa Hane': How Tobacco Saved the World from Destruction and Healed the People

Nát'oh Baa Hane':How Tobacco Saved the World from Destruction and Healed the People Avery Denny (bio), Adrian Lerma (bio), and Michael Lerma (bio) There comes a time in life, and in history, when we must be reminded and be retaught about wellness of life—what to do and not to do. On the Navajo Nation, we look around and see young people who are unaware of things that can be harmful to their health. It is our responsibility, as adults, to teach and provide guidelines for their safety needs. This is a Fundamental Law of the Navajo. Today, we all need a good lesson about life. We need to hear it repeatedly to be reminded of life's philosophy of Są'ah Naagháí Bik'ehózhóón, which reminds us that living a good healthy life includes keeping our mind, spirit, soul, and body clean. These lessons of living are not meant to put people down, insult, or embarrass them. These teachings are meant to help get people out of addiction. Many times, all we need is to have someone open our minds allowing us to escape narrow-mindedness. We need a holistic spiritual vantage point of the world. We also need that holistic spiritual view of ourselves, and our relatives. The mind and body manifest a desire to indulge in new educational perspectives. It is natural for our minds to have thirst and hunger for knowledge. Let us feed our minds and bodies with spiritual knowledge. Navajo Hataałii (Chanters) are trained to see to the needs of The People, to maintain their well-being, and to attend to the duty of saving a life. We seek the spirituality in life that is associated with nature and the Holy People, and we journey to better understand longevity and wisdom. As healers and guides, we give our concern with passion, and we believe that without spiritual healing, we will all suffer down the road. That is why we are sharing knowledge to save your internal organs and insist that you take care of your body and mind by not contaminating them with unhealthy chemical substances. It is said that all people should live to be 102 years old as this is the ideal age. We want you to be healthy and able-bodied experiencing minimal difficulties. With healing and prevention, we can walk on the correct path of life, which is also identified as the Corn Pollen Road of Life. There are options to turn your life around, to get rid of bad habits that are health hazards. Please choose the life of healthy living in your future. The end is never too soon in this journey of a lifetime. Many people are smart enough to know not to smoke commercial and electronic [End Page 1086] cigarettes, but still cut their lives short by contaminating their lungs. If only we intervened earlier, these relatives would still be alive. Nevertheless, it's not too late to help by sharing the teachings about the dangers of chemical tobacco use. The proper use of Navajo traditional Nát'oh (mountain tobacco) needs to be mentioned at this point. It is a medicinal herb utilized for healing in traditional Navajo ceremony known as "Nahagha." If it is abused, it will become a danger to your health. It should only be used in a prescribed way, to heal and nurture. Abusing Nát'oh will destroy your life and kill you, so quit and leave it alone. Live a long time. No need to smoke to pass time. Instead, smoke in ceremonies for treatment. We are responsible for taking care of our loved ones' lives by educating them with what we know and sharing our experiences. We respect young people's learning abilities, and we want them to live wisely and take life seriously. We hope we all succeed to make change for the better of all. Tobacco People In this section, and in the sections that follow, the information utilized to describe and enhance the understanding of tobacco is taken directly from Diné baa hane', or the Navajo creation account. In this account, each of the Four Worlds had conflict that...

Risk assessment of pollen‐mediated gene flow from Ga1‐m field corn to dent‐sterile Ga1‐s popcorn

AbstractThe popcorn industry in the United States is at risk of genetic contamination because it utilizes the gametophyte factor 1 gene (Ga1) as a barrier against pollen‐mediated gene flow (PMGF) from field corn (Zea mays L.). Popcorn with the Ga1‐s allele accepts pollen only from Ga1‐s corn, allowing for field corn and popcorn to be nearby without isolation. Germplasm is being introduced to the United States to increase field corn diversity that unknowingly contains the Ga1‐m allele, which can overcome Ga1‐s selectivity and pollinate popcorn. The risk to the popcorn industry has been underassessed. Experiments were conducted to model the frequency of PMGF from Ga1‐m field corn to Ga1‐s popcorn under field conditions and to evaluate the role of wind speed and direction using a concentric donor–receptor design in 2017 and 2018 in Nebraska, USA. The PMGF to white popcorn was detected using a field corn pollen donor with yellow kernel color (dominate) and further confirmed with a molecular test. Popcorn kernels were harvested from cardinal and ordinal directions from 1 to 70 m. More than 7 million kernels were screened to detect the PMGF. Information‐theoretic criteria were used to select the best‐fit model. The greatest PMGF (1.6– 4.1%) was detected at 1 m and declined with distance. The PMGF was detected at 70 m, the maximum distance tested. Amplification of Ga1 followed by restriction enzyme digest confirmed that yellow kernelled progeny were hybrids from the result of PMGF. This is the first assessment of PMGF from field corn to popcorn, and the results are alarming for the popcorn industry and export market.

Controls on fine particle retention in experimental streams

The transport and retention of fine particulate organic matter (FPOM) in headwater streams plays a significant role in organic matter processing and represents a critical link between upstream and downstream systems. Benthic biofilms potentially alter substrate characteristics and dynamics. However, the influence of biofilm colonization on FPOM retention has not been well documented, likely due to inherent heterogeneity of natural systems. We expected that biofilm growth would either enhance or diminish FPOM retention in the streambed, whereas biofilm growth would vary depending on the underlying substrate template. We used a short-term FPOM addition technique to estimate transport distances of a fine particle analog (corn pollen: 70 μm) in four 50-m experimental streams (Q = 1.5 L/s) at the Notre Dame Linked Experimental Ecosystem Facility. Streams varied in substrate size (1-cm pea gravel vs 10-cm small cobble) and complexity (homogenous 50/50 mix vs alternating sections). We sampled streams on multiple dates over 5 mo (June–October) of biofilm colonization and senescence. While FPOM transport distances generally increased as biofilm colonization occurred, retention was variable across streams and over time. We found no consistent or simple pattern of FPOM retention in our streams. Rather, one of the strongest effects was an indirect relationship between FPOM removal and transient storage, a factor that is strongly driven by biofilm colonization. These results emphasize the dynamic feedback of the physical and biological environments influencing FPOM retention in streams.

Honey bee colony-level exposure and effects in realistic landscapes: An application of BEEHAVE simulating clothianidin residues in corn pollen.

Discerning potential effects of insecticides on honey bee colonies in field studies conducted under realistic conditions can be challenging because of concurrent interactions with other environmental conditions. Honey bee colony models can control exposures and other environmental factors, as well as assess links among pollen and nectar residues in the landscape, their influx into the colony, and the resulting exposures and effects on bees at different developmental stages. We extended the colony model BEEHAVE to represent exposure to the insecticide clothianidin via residues in pollen from treated cornfields set in real agricultural landscapes in the US Midwest. We assessed their potential risks to honey bee colonies over a 1‐yr cycle. Clothianidin effects on colony strength were only observed if unrealistically high residue levels in the pollen were simulated. The landscape composition significantly impacted the collection of pollen (residue exposure) from the cornfields, resulting in higher colony‐level effects in landscapes with lower proportions of semi‐natural land. The application of the extended BEEHAVE model with a pollen exposure‐effects module provides a case study for the application of a mechanistic honey bee colony model in pesticide risk assessment integrating the impact of a range of landscape compositions. Environ Toxicol Chem 2019;38:423–435. © 2018 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.

Influence of Feeding with different Plant Pollens on Prey- Stage Preference and Predation Rate of Neoseiulus Californicus (Mcgregor) (Acari: Phytoseiidae)

Neoseiulus californicus (Acari: Phytoseiidae) is an effective predator in greenhouses which feeds on plant injurious mites. Searching capacity is one of importance in the effectiveness of this predatory mite. In this research, the population fed with corn pollen, walnut and date pollen and the spider mite (four strains) were investigated. The prey-stage preference of N. californicus was studied on different developmental stages of Tetranychus urticae. The predation rate of rearing population of N. californicus was determined; it was used eggs of T. urticae. Experiments were carried out on strawberry disc in Petri dish (6 cm diameter) under laboratory conditions (27±1ºC temperature, 70±5% RH and 16L: 8D photoperiod). After 24 hours, the total numbers of prey consumed were counted. The predatory mites reared on different pollens prefer eggs or nymphs to adults and the Preference Index of different strains was not different. Result of consumed of spider mites by female predatory mites indicated the predation rate of the predatory mites fed with corn pollen (9±1.46), walnut pollen (8.19±0.99) and Date pollen (8.28±0.80) did not any significant difference, however when spider mites and the mentioned pollens were used, the predation rate of predatory mites when fed with T. urticae (14.74±0.94), Walnut (15.24±1.05) and date pollen (14.17±1.04) show significant difference with the population of corn pollen (10.0±0.95). The predation rate of four strains decreased at present of plant pollens. Use of the predatory mite fed with the different developmental stage of two-spotted spider mite and pollen in the biological control of the pests is useful.

Identification of cattail pollen, pine pollen and bee pollen by Fourier transform infrared spectroscopy and two-dimensional correlation infrared spectroscopy

Cattail pollen (CP) and pine pollen (PP) are traditional Chinese medicine, which are used for bleeding blood and immunity enhancement activity respectively. Due to the economic benefits, they are occasionally adulterated with bee pollen. In this study, CP, PP and 6 kinds of bee pollen (dandelion pollen, sunflower pollen, lotus pollen, rhus pollen, buckwheat pollen, corn pollen) were collected and observed by the scanning electron microscope. And then, Fourier transform infrared (FT-IR) spectroscopy and two-dimensional correlation infrared (2D-IR) spectroscopy were used to identify and analyze these 8 kinds of pollens. It is found that PP and CP could be identified from bee pollen through the position, intensity and shape of saccharide and protein characteristic peaks in the FT-IR spectra. The FT-IR spectra of PP, CP and bee pollen are almost similar. 2D-IR spectra exhibited significant differences in automatic peak positions, especially in the range of 760–1400 cm−1. CP and PP have three consistently strong automatic peaks around 1150, 1204, and 1233 cm−1. The sequences of the absorption intensities of them all are 1204 cm−1 > 1233 cm−1 > 1150 cm−1. While CP has no obvious strong automatic peaks compared with PP in the range of 830–1140 cm−1. In conclusion, FT-IR and 2D-IR technology are the effective method for distinguish CP and PP from these 6 kinds of bee pollen.

Effect of different natural and factitious diets on development and life history parameters of Chilocorus bipustulatus

The effects of five diets consisting of two natural prey (Acanthococcus abaii Danzig and Aganoscena pistaciae Burckhardt et Lauterer) and three factitious foods (frozen eggs of Ephestia kuehniella Zeller, a mixture of frozen corn pollen with eggs of E. kuehniella and a diet consisting of eggs of Sitotroga cerealella Olivier) on the development, survival and reproduction of Chilocorus bipustulatus L. were investigated. The results revealed that this predator successfully completed immature developmental procedures on the offered foods, but developmental duration was affected. Total larval survival of C. bipustulatus was higher on natural diets than factitious diets. Fresh weights of the newly emerged female and male coccinellids were also affected by the diet offered to this predator during their larval stage. The highest intrinsic rate of increase (r), the net reproductive rate (R 0) and the finite rate of increase (λ) were obtained on A. pistaciae, and these values were significantly different from A. abaii.

Spiders from multiple functional guilds are exposed to Bt-endotoxins in transgenic corn fields via prey and pollen consumption

ABSTRACTA comprehensive assessment of risk to natural enemies from Bt-endotoxins from bioengineered crops must evaluate potential harm, as well as exposure pathways in non-target arthropod food webs. Despite being abundant generalist predators in agricultural fields, spiders (Araneae) have often been overlooked in the context of Bt crop risk assessment. Spiders and their prey were collected from transgenic corn fields expressing lepidopteran-specific Cry1Ab, coleopteran-specific Cry3Bb1, both proteins, and a non-transgenic near isoline. Spiders and prey were screened for Cry1Ab and Cry3Bb1 using qualitative enzyme-linked immunosorbent assay. Spiders from the three most common functional guilds, wandering sheet-tangle weavers, orb-weavers, and ground runners, tested positive for Cry1Ab and Cry3Bb1 proteins, with the highest per cent positive (8.0% and 8.3%) during and after anthesis. Laboratory feeding trials revealed that Bt-endotoxins were detectable in the Pardosa sp. (Lycosidae)-immature cricket-Bt corn pathway, but not in the Tennesseellum formica (Linyphiidae)-Collembola-Bt corn pathway. Additionally, direct consumption of transgenic corn pollen by Pardosa sp., T. formica, and Cyclosa turbinata (Araneidae) resulted in transfer of both Cry1Ab and Cry3Bb1 endotoxins. This study demonstrates that Bt-endotoxins are taken up by diverse members of a spider community via pollen and prey consumption and should be factored into future risk assessment.