Effects of culture age on conidia production, viability and pathogenicity of Dactylaria higginsii.

Effects of culture age on conidia production, viability and pathogenicity of Dactylaria higginsii, a potential bioherbicide for controlling Cyperus rotundus (purple nutsedge) were investigated both in the laboratory and the greenhouse. This fungus was capable of producing conidia after five days of culturing on potato dextrose agar (PDA), with the highest conidia production obtained from the 15 day-old culture compared to other culture ages. Conidia harvested from 15 days of culturing on PDA, produced higher viability and were more pathogenic to purple nutsedge compared to conidia harvested before or after 15 days of culturing. The infection rate of conidia harvested from the 15 day-old cultures was faster (rL0.40 logit/day) compared to the infection rate of conidia harvested from other culture ages

Grafting and Paladin Pic-21 for Nematode and Weed Management in Vegetable Production

Two years of field trials conducted in a Meloidogyne incognita-infested field evaluated grafting and Paladin Pic-21 (dimethyl disulfide:chloropicrin [DMDS:Pic] 79:21) for root-knot nematode and weed control in tomato and melon. Tomato rootstocks evaluated were; 'TX301', 'Multifort', and 'Aloha'. 'Florida 47' was the scion and the nongrafted control. A double crop of melon was planted into existing beds following tomato harvest. Melon rootstocks, C. metulifer and 'Tetsukabuto', were evaluated with nongrafted 'Athena' in year 1. In year 2, watermelon followed tomato with scion variety 'Tri-X Palomar' as the control and also grafted onto 'Emphasis' and 'Strongtosa' rootstocks. Four soil treatments were applied in fall both years under Canslit metalized film; Paladin Pic-21, methyl bromide:chloropicrin (MeBr:C33, 67:33), Midas (iodomethane:chloropicrin 50:50), and a herbicide-treated control. M.incognita J2 in soil were highest in herbicide control plots and nongrafted tomato. All soil treatments produced similar tomato growth,which was greater than the herbicide control. All treatments reduced M. incognita J2 in roots compared to the herbicide control. 'Multifort' rootstock produced the largest and healthiest roots; however, the number of M. incognita isolated from roots did not differ among the tomato rootstocks tested. Galling on tomato was highest in herbicide control plots and nongrafted plants. In melon, M.incognita J2 in soil did not differ among melon rootstocks, but numbers isolated from melon rootstocks increased in 'Tetsukabuto' compared with C. metuliferus. 'Tetsukabuto' were larger root systems than nongrafted 'Athena'. All fumigants provided protection for all melon rootstocks against galling by M.incognita compared to the herbicide control. Galling on C. metuliferus rootstock was less in all fumigant treatments compared with nongrafted 'Athena' and 'Tetsukabuto'. In watermelon, M. incognita in soil and roots did not differ among soil treatments or watermelon rootstocks, and yield was lower in both grafted rootstocks compared with the nongrafted control. All soil treatments increased average fruit weight of watermelon compared with the herbicide control, and provided effective weed control, keeping the most predominant weed, purple nutsedge (Cyperus rotundus L.), density at or below 1/m row. Grafting commercial scions onto M. incognita-resistant rootstocks has potential for nematode management combined with soil treatments or as a stand-alone component in crop production systems

Association Analysis of the FTO Gene with Obesity in Children of Caucasian and African Ancestry Reveals a Common Tagging SNP

Recently an association was demonstrated between the single nucleotide polymorphism (SNP), rs9939609, within the FTO locus and obesity as a consequence of a genome wide association (GWA) study of type 2 diabetes in adults. We examined the effects of two perfect surrogates for this SNP plus 11 other SNPs at this locus with respect to our childhood obesity cohort, consisting of both Caucasians and African Americans (AA). Utilizing data from our ongoing GWA study in our cohort of 418 Caucasian obese children (BMI≥95th percentile), 2,270 Caucasian controls (BMI<95th percentile), 578 AA obese children and 1,424 AA controls, we investigated the association of the previously reported variation at the FTO locus with the childhood form of this disease in both ethnicities. The minor allele frequencies (MAF) of rs8050136 and rs3751812 (perfect surrogates for rs9939609 i.e. both r2 = 1) in the Caucasian cases were 0.448 and 0.443 respectively while they were 0.391 and 0.386 in Caucasian controls respectively, yielding for both an odds ratio (OR) of 1.27 (95% CI 1.08–1.47; P = 0.0022). Furthermore, the MAFs of rs8050136 and rs3751812 in the AA cases were 0.449 and 0.115 respectively while they were 0.436 and 0.090 in AA controls respectively, yielding an OR of 1.05 (95% CI 0.91–1.21; P = 0.49) and of 1.31 (95% CI 1.050–1.643; P = 0.017) respectively. Investigating all 13 SNPs present on the Illumina HumanHap550 BeadChip in this region of linkage disequilibrium, rs3751812 was the only SNP conferring significant risk in AA. We have therefore replicated and refined the association in an AA cohort and distilled a tag-SNP, rs3751812, which captures the ancestral origin of the actual mutation. As such, variants in the FTO gene confer a similar magnitude of risk of obesity to children as to their adult counterparts and appear to have a global impact

Report of the Berry Working Group (Strawberry, Raspberry/Blackberry, Blueberry)

Strawberries are a relatively recently domesticated crop. The most commonly cultivated strawberry, Fragaria x ananassa, is a hybrid of the North American F. virginiana and the South American F. chiloensis (Maas 1998). These parental species are still grown in some areas and F. virginiana is the primary wild, sexually compatible relative to the cultivated strawberry. In addition to F. virginiana, F. vesca and its subspecies are also present in the United States. Fragaria x ananassa and F. virginiana readily cross. Introgression of pest resistance traits into the wild strawberry population is likely, as substantial amounts of crop-weed introgression has already occurred throughout the midwest, northeast, and southeast United States (Jim Hancock pers. comm.). Introgression has occurred to the extent that it is difficult to find “pure” populations of Fragariae virginiana in many areas. Strawberries suffer from several limiting diseases, insects, nematodes, and weed problems (Table 1)

Soil Amendment and Storage Effect the Quality of Winter Melons (<i>Benincasa hispida</i> (Thunb) Cogn.) and Their Juice

Winter melon fruits were grown in the field using anaerobic soil disinfestation (ASD) and conventional fertilizer alone as the control treatment. Fruits were harvested and stored at 20 °C for 120 d, the juice was processed on day one and day 120, and the effects of soil amendment and 120 d storage on the juice’s physical and chemical (sugars, acids, volatile and nutritional compounds) properties were evaluated. Fruit juice extracted from ASD-grown fruit had greater magnitude of zeta potential than the control juice, indicating it was physically more stable than the juice obtained from the control conditions. ASD fruit juice had lower soluble solids content (SSC), and lower volatile compounds that contribute green, grass, and sulfur notes, and negatively influence flavor quality. ASD fruit juice had higher vitamin B5 and cytidine. Juice processed from 120 d stored fruit had less yield due to 12.4–15.6% weight loss. The non-soluble solids content was higher and particle size was larger, and the SSC and individual sugars decreased. However, titratable acidity (TA) increased primarily due to increased citric acid. Out of 16 free amino acids, 6 increased and only 1 decreased. However, three out of five nucleosides decreased; vitamins B1 and B6 increased; vitamins B2, B3 and C decreased. Overall, juice derived from fruit produced using ASD was physically more stable and had less SSC and off-odor volatiles than the control, while the fruit juice of those stored for 120 d had lower SSC and higher TA and nutritional profiles, comparable to freshly harvested fruit

Zinc and Iron Agronomic Biofortification of Brassicaceae Microgreens

Insufficient or suboptimal dietary intake of iron (Fe) and zinc (Zn) represent a latent health issue affecting a large proportion of the global population, particularly among young children and women living in poor regions at high risk of malnutrition. Agronomic crop biofortification, which consists of increasing the accumulation of target nutrients in edible plant tissues through fertilization or other eliciting factors, has been proposed as a short-term approach to develop functional staple crops and vegetables to address micronutrient deficiency. The aim of the presented study was to evaluate the potential for biofortification of Brassicaceae microgreens through Zn and Fe enrichment. The effect of nutrient solutions supplemented with zinc sulfate (Exp-1; 0, 5, 10, 20 mg L&minus;1) and iron sulfate (Exp-2; 0, 10, 20, 40 mg L&minus;1) was tested on the growth, yield, and mineral concentration of arugula, red cabbage, and red mustard microgreens. Zn and Fe accumulation in all three species increased according to a quadratic model. However, significant interactions were observed between Zn or Fe level and the species examined, suggesting that the response to Zn and Fe enrichment was genotype specific. The application of Zn at 5 and 10 mg L&minus;1 resulted in an increase in Zn concentration compared to the untreated control ranging from 75% to 281%, while solutions enriched with Fe at 10 and 20 mg L&minus;1 increased Fe shoot concentration from 64% in arugula up to 278% in red cabbage. In conclusion, the tested Brassicaceae species grown in soilless systems are good targets to produce high quality Zn and Fe biofortified microgreens through the simple manipulation of nutrient solution composition

Evaluation of Steam and Soil Solarization for Meloidogyne arenaria Control in Florida Floriculture Crops

Steam and soil solarization were investigated for control of the root-knot nematode Meloidogyne arenaria in 2 yr of field trials on a commercial flower farm in Florida. The objective was to determine if preplant steam treatments in combination with solarization, or solarization alone effectively controlled nematodes compared to methyl bromide (MeBr). Trials were conducted in a field with naturally occurring populations of M. arenaria. Treatments were solarization alone, steam treatment after solarization using standard 7.6-cm-diameter perforated plastic drain tile (steam 1), steam treatment following solarization using custom-drilled plastic drain tile with 1.6-mm holes spaced every 3.8 cm (steam 2), and MeBr applied at 392 kg/ha 80:20 MeBr:chloropicrin. Drain tiles were buried approximately 35 cm deep with four tiles per 1.8 by 30 m plot. Steam application followed a 4-wk solarization period concluding in mid-October. All steam was generated using a Sioux propane boiler system. Plots were steamed for sufficient time to reach the target temperature of 708C for 20 min. Solarization plastic was retained on the plots during steaming and plots were covered with a single layer of carpet padding to provide additional insulation. The floriculture crops larkspur (Delphinium elatum and Delphinium X belladonna), snapdragon (Antirrhinum majus), and sunflower (Helianthus annuus) were produced according to standard commercial practices. One month after treatment in both years of the study, soil populations of M. arenaria were lower in both steam treatments and in MeBr compared to solarization alone. At the end of the season in both years, galling on larkspur, snapdragon, and sunflowers was lower in both steam treatments than in solarization. Both steam treatments also provided control of M. arenaria in soil at the end of the season comparable to, or exceeding that provided by MeBr. Both steam treatments also reduced M. arenaria in snapdragon roots comparable to, or exceeding control with MeBr. Meloidogyne arenaria in soil increased in solarization alone. Solarization alone also had higher gall ratings on larkspur, snapdragon, and sunflower than all other treatments. Steam provided excellent control of M. arenaria in this study