Implementation of simple sequence repeat markers to genotype Florida strawberry varieties

Simple sequence repeats (SSRs or microsatellites) are frequently used as a robust, rapid, and relatively inexpensive means of genotyping. Recent reports in cultivated strawberry (Fragaria × ananassa) have identified a widely applicable set of SSRs that permits discrimination of closely-related genotypes. In the present study this same set of SSRs is analyzed in cultivars commonly grown in the state of Florida, as well as advanced breeding selections from the University of Florida program. Nine primer pairs have been used to produce discrete SSR patterns for all lines tested, including diagnostic sets that distinguish between closely-related cultivars and/or breeding selections. A comparison of markers to known pedigrees is presented, along with analysis of relative relatedness between lines studied. We also detail important technical considerations for transferability and limitations of these technologies between laboratories. The resulting genotype data for cultivars commonly used in Florida are accessible as supplemental data in graphic format and allow comparison with other cultivars. Users can thus select the most diagnostic SSRs to test the lines in question. These resources provide new tools for breeders and nurseries to authenticate genotypes, follow inheritance patterns and enforce patent protection. As important, this report underscores the strengths and weaknesses of applying the original methodologies to a different plant population in independent laboratories.     

Physicochemical control of durum wheat grain filling and glutenin polymer assembly under different temperature regimes

Durum wheat is grown in the Mediterranean area where drought and high temperature frequently prevail and impact grain texture, composition and yield. The purpose of this work was to examine the effect of high temperature on grain development and final composition according to the timing of exposure. High temperature (up to 27.5 °C) was applied either during the linear grain filling or drying phases or during whole grain development. The dynamics of grain dry mass, water, glutenin polymers, and protein bodies during grain development were determined. Irrespective of high temperature timing, the arrest of grain filling was observed at 45.9% grain moisture content. At that point, starch granules included in endosperm cells reached their physical packing limit, limiting further deposits. HT applied before physiological maturity shortened the duration of grain filling and resulted in a significant increase in grain protein concentration and in the proportion of vitreous grain. Late formation of sodium dodecyl sulfate (SDS)-insoluble glutenin polymers below 32% grain moisture content was also favored. The ability of wheat storage protein to form a viscoelastic matrix embedding starch granules at the beginning of grain desiccation is proposed to be mandatory for gaining vitreous grains and a high proportion of SDS-insoluble glutenin polymers.     

Perioperative risk factors for mortality and length of hospitalization in mares with dystocia undergoing general anesthesia: A retrospective study

This study investigated associations between perioperative factors and probability of death and length of hospitalization of mares with dystocia that survived following general anesthesia. Demographics and perioperative characteristics from 65 mares were reviewed retrospectively and used in a risk factor analysis. Mortality rate was 21.5% during the first 24 h post-anesthesia. The mean ± standard deviation number of days of hospitalization of surviving mares was 6.3 ± 5.4 d. Several factors were found in the univariable analysis to be significantly associated (P < 0.1) with increased probability of perianesthetic death, including: low preoperative total protein, high temperature and severe dehydration on presentation, prolonged dystocia, intraoperative hypotension, and drugs used during recovery. Type of delivery and day of the week the surgery was performed were significantly associated with length of hospitalization in the multivariable mixed effects model. The study identified some risk factors that may allow clinicians to better estimate the probability of mortality and morbidity in these mares.     

Isolation and Characterization of Phenol-Degrading Psychrotolerant Yeasts

Water, Air, & Soil Pollution - To investigate the differential contribution of extracellular polymeric substances (EPS) to polycyclic aromatic hydrocarbon (PAH) degradation by fungi and...     

Evaluation of aggregate stability of Haplic Stagnosols using dynamic light scattering,phase analysis light scattering and color coordinates

Dynamic light scattering and phase analysis light scattering have been used to study organo-clay complexes and aggregate stability of Haplic Stagnosols depending on land use. The study of agricultural soils afforested for 45 years showed that the value of the effective diameter of organo-clay complexes slightly decreased compared to that in arable soil but remains still higher than that in the forest soil. Multiple linear regression statistical models were developed to predict the effective diameter of the particles. The best model (r = 0.95), where all parameters were significant (P < 0.05), included the clay content, clay carbon concentration, total iron (Fe_t) and soil color coordinates (L*, a*, b*). In the upper horizons, the effective diameter depends on the organic matter content, whereas iron oxides with surfaced position play the main role in the underlying horizons. Intensive tillage moves the colloidal system to coagulation and after withdrawal of arable Haplic Stagnosol from the agricultural production, the colloidal system tends to restore its peptization stability. However, it should be noted that the afforestation period (45 years) of arable Haplic Stagnosols is not enough for a full recovery of organo-clay complexes peptization stability.     

Can the polyculture with South American catfish improve the feeding efficiency of rainbow trout culture?

The objective of this study was to determine if the South American catfish (Rhamdia quelen) is suitable to be farmed in polyculture with rainbow trout (Oncorhynchus mykiss) in intensive systems during the juvenile phase to maximize feed efficiency. Juveniles of rainbow trout (3.94?±?0.11 g) and South American catfish (2.07?±?0.04 g) were distributed in 16 tanks (100 L) with continuous water renewal at the density of 50 fish/tank. The experimental design was completely randomized with four treatments (proportions between species) and four replicates. The treatments were 100% trout (100T), 70% trout and 30% catfish (70T30C), 50% trout and 50% catfish (50T50C), and 100% catfish (100C). Fish were fed twice daily with pelleted commercial feed (45% crude protein) during an experimental period of 56 days. No feed was provided for the catfish in polyculture. The weight gained by the trout was higher in polyculture. Fish survival did not differ among the treatments. The average survival of the trout in all tanks was 99.6?±?1.0%, while the survival of the South American catfish was 97.9?±?2.7%. The total feed conversion ratio was lower in the 70T30J treatment, followed by the 100T treatment. Rainbow trout and South American catfish are compatible species for farming together in the first phase of their juvenile development. The different spaces occupied by these species inside tanks probably prevent competition or agonistic behavior. Catfish eat the non-ingested leftover diet from the trout, which improves feed conversion and increases sustainability.