Vegetative propagation of Colutea istria Mill. from leafy stem cuttings

This study investigates the optimal conditions for the vegetative propagation of the multipurpose leguminous shrub Colutea istria from leafy stem cuttings. The conditions examined included 1) the origin of the cutting (apical, medial or basal), 2) indole-3-butyric acid (IBA) treatment (0, 50, 200 or 400 mg/l), 3) the relative humidity of the propagation environment (high or low), 4) wounding base of cutting, and 5) the season in which the cutting was taken. The rooting ability of the cuttings was significantly influenced by all these factors. Winter cuttings obtained from the middle and base of the branch showed a greater rooting capacity than those harvested from the apical area, while autumn cuttings harvested from the middle and apical areas of the branch showed a greater rooting capacity than those harvested from the base. Winter cuttings showed the best rooting capacity than autumn cuttings. IBA treatment (200 mg/l), high humidity (98-100%), and wounding increased the rooting capacity of the cuttings. The sprout of new leaves was higher in basal cuttings, while IBA and wounding also significantly enhanced the root number of rooted cuttings. A method for vegetatively propagating C. istria plants is given.     

Characterization of the interaction between two food aroma components, alpha-pinene and ethyl butyrate, and ethylene-vinyl alcohol copolymer (EVOH) packaging films as a function of environmental humidity

The ethylene-vinyl alcohol copolymers (EVOHs) are well-known high oxygen barrier materials that are being used successfully in the design of packaging structures for oxygen-sensitive food or pharmaceutical products. Recently, there has been increasing interest in using EVOH materials to provide a high barrier to organic compounds as a means to reduce food aroma scalping. However, the barrier function of this family of materials diminishes significantly in humid environments, and it is supposed that so does the organic vapor barrier. In this work, a new sorption-based method to characterize the interaction between food aroma and polymer films for packaging as a function of relative humidity is presented and is used to determine the barrier to ethyl butyrate and alpha-pinene of EVOH at 23 degrees C. The results show that although EVOH is an excellent barrier to food aroma when dry, a property that even improves at low relative humidity (RH), the solubility and diffusivity of the compounds tested increase dramatically with humidity at medium to high water activities. However, even in the worst case (100% RH), EVOH outperforms low-density polyethylene (LDPE) as a barrier to organic vapors at least 500,000-fold.     

Effect of formic acid on performance, digestibility, intestinal histomorphology and plasma metabolite levels of broiler chickens

1. The effect of dietary formic acid on performance, digestibility, intestinal histomorphology and plasma metabolite levels of broiler chickens was studied. 2. An experiment with 120 Ross male broiler chickens was conducted from 1 to 42 d of age at the laboratory. There were 4 treatment groups: control (C), 10 mg/kg feed avilamycin (AV) and formic acid at two concentrations, 5 and 10 g/kg feed (FA5 and FA10, respectively). 3. No differences in weight gain, feed intake or feed conversion ratio were observed in male broiler chickens fed on the different diets. 4. An effect of the additives on ileal dry matter (DM) digestibility at 42 d of age was detected with the finisher diets; AV and 10 g/kg of feed formic acid slightly improved ileal DM digestibility compared to the other treatment groups. 5. Jejunum pH was not affected when 5 or 10 g/kg formic acid was added, and the results do not clearly show a positive effect of formic acid on the intestinal histomorphology. 6. No differences were noticed for blood metabolites in the different diets, and the levels of calcium and phosphorus in the plasma were not altered by formic acid addition. 7. In conclusion, when using broiler chickens under conditions of good hygiene, dietary formic acid did not have a clear positive effect on performance, intestinal histomorphology or plasma metabolite levels; however, there was a slight positive effect on the ileal digestibility of nutrients.     

Reproductive resilience: a paradigm shift in understanding spawner‐recruit systems in exploited marine fish

A close relationship between adult abundance and stock productivity may not exist for many marine fish stocks, resulting in concern that the management goal of maximum sustainable yield is either inefficient or risky. Although reproductive success is tightly coupled with adult abundance and fecundity in many terrestrial animals, in exploited marine fish where and when fish spawn and consequent dispersal dynamics may have a greater impact. Here, we propose an eco‐evolutionary perspective, reproductive resilience, to understand connectivity and productivity in marine fish. Reproductive resilience is the capacity of a population to maintain the reproductive success needed to result in long‐term population stability despite disturbances. A stock's reproductive resilience is driven by the underlying traits in its spawner‐recruit system, selected for over evolutionary timescales, and the ecological context within which it is operating. Spawner‐recruit systems are species specific, have both density‐dependent and fitness feedback loops and are made up of fixed, behavioural and ecologically variable traits. They operate over multiple temporal, spatial and biological scales, with trait diversity affecting reproductive resilience at both the population and individual (i.e. portfolio) scales. Models of spawner‐recruit systems fall within three categories: (i) two‐dimensional models (i.e. spawner and recruit); (ii) process‐based biophysical dispersal models which integrate physical and environmental processes into understanding recruitment; and (iii) complex spatially explicit integrated life cycle models. We review these models and their underlying assumptions about reproductive success vs. our emerging mechanistic understanding. We conclude with practical guidelines for integrating reproductive resilience into assessments of population connectivity and stock productivity.     

A domain-specific language framework for farm management information systems in precision agriculture

Precision Agriculture - Farm management information system (FMIS) is an important element of precision agriculture to support the decision making process in the agricultural business. Developing...     

Ontogeny and total sugar content of yacon tuberous roots and other three Smallanthus species (Heliantheae,Asteraceae), insights on the development of a semi-domesticated crop

The ontogeny of the tuberous roots of yacon (Smallanthus sonchifolius), an ancient Andean crop, is described for the first time along with three other wild species of Smallanthus: S. connatus, S. macroscyphus and S. siegesbeckius. Tuberous storage roots are present in the four species. Tuberization results from unusual secondary thickening. A meristematic endodermis maintains the primary cortex by generating cortex cells continuously. Secretory schizogenous canals develop adjacent to the endodermis in opposition to the phloem poles. Phellogen originates in the outer layers of the parenchymatic cortex. The four species develop a parenchymatous pith that stores mainly fructooligosacharides (FOS) and plays an important role in storing water, protecting the plant from drought stress and environmental hazards in the Andean climate. In yacon, domestication has produced a wide pith that stores water, reducing sugars and FOS with low degree of polimerization, that could have eventually made it more palatable as compared to the wild counterparts.     

Detection of Eutypa lata and Eutypella vitis in Grapevine by Nested Multiplex Polymerase Chain Reaction

ABSTRACT Two fungi were isolated from grapevines in Michigan vineyards with Eutypa dieback symptoms: Eutypa lata and Eutypella vitis. These fungi are difficult to distinguish morphologically but are genetically distinct as determined by sequencing of the internal transcribed spacer (ITS) regions. The ITS regions of 25 Eutypa lata and 15 Eutypella vitis isolates were sequenced. Eutypa lata sequences were more variable than those of Eutypella vitis. Polymerase chain reaction (PCR) primers were designed for each species and evaluated against isolates of both fungi as well as 11 closely related Diatrypaceous fungi and 23 isolates of other fungi representing various pathogenic, saprophytic, and endophytic genera on grape and other small fruit crops. The primers were specific for their intended species. A nested multiplex PCR protocol was developed and used to successfully detect these fungi in wood samples from cankers with and without stromata from naturally infected vines as well as in artificially inoculated, potted canes. The primers developed in this study will assist in our abilities to diagnose and study the roles of Eutypa lata and Eutypella vitis in Eutypa dieback development.     

Controlled atmosphere storage of wild strawberry fruit (Fragaria vesca L.)

Controlled atmosphere storage technology to extend the shelf life of "Reina de los Valles" wild strawberry fruit (Fragaria vesca L.) was studied. Fruits were stored at 3 degrees C for three weeks in different atmosphere compositions: 0.05% CO2/21% O2 (air), 3% CO2/18% O2, 6% CO2/15% O2, 10% CO2/11% O2, and 15% CO2/6% O2. The effect of gas composition on soluble solids content, titrable acidity, pH, off-flavor, aroma volatiles, and consumer preference was monitored. The result showed that the 10% CO2/11% O2 combination can efficiently prolong the shelf life of wild strawberries by maintaining the quality parameters within acceptable values, through inhibiting the development of Botrytis cinerea, without significantly modifying consumer acceptance.     

Estimation of grain yield by near-infrared reflectance spectroscopy in durum wheat

Near-infrared Reflectance Spectroscopy (NIRS) is widely used for routine, non-destructive assessment of grain quality in cereals. In this work, we assess the use of NIRS as an indirect indicator of grain yield (GY) in durum wheat grown in Mediterranean conditions. Plants were grown under rain-fed conditions in two sites in NW Syria, Breda and Tel Hadya, and a third trial was planted at Tel Hadya under support irrigation. We measured the spectral reflectance signature between 1100 and 2500 nm in flour from the same grains harvested for yield determination. By Partial Least Squares (PLSR), we obtained a model of the association between agronomic determinations of GY and these spectra. We found significant (p < 0.001) relationships between GY and NIRS-predicted values, with r ²= 0.36 (N= 96), r ²= 0.72 (N= 72) and r ²= 0.52 (N= 138) in Breda, and Tel Hadya rainfed and irrigated, respectively. Full cross validation of these models gave r ² between 0.31 and 0.33 (p < 0.001). When we applied the models to the samples from the other two trials, we found a general decrease in their predictive ability. Compared with other grain traits (carbon isotope discrimination, grain weight, ash and nitrogen content), NIRS showed a similar or even stronger relationship with GY, at least when validated in the same trial. We concluded that NIRS could be used to rank GY during the early generations of a breeding program, when performing yield trials is less feasible. However, further research is required to identify the environments in which this technique is more reliable, as well as to evaluate the heritability of NIRS-predicted GY.     

Development of active polyvinyl alcohol/β-cyclodextrin composites to scavenge undesirable food components

Active food packaging systems based on the incorporation of agents into polymeric package walls are being designed to purposely release or retain compounds to maintain or even increase food quality. The objective of this work was to develop polyvinyl alcohol (PVOH)/β-cyclodextrin (βCD) composite films that can be applied to reduce undesirable component content such as cholesterol in foods through active retention of the compounds in the package walls during storage. Cyclodextrins were added to PVOH in a proportion of 1:1 and cross-linked with glyoxal under acidic media to reduce its water-soluble character. Three different cross-linking procedures were used: cross-linking of the polymer/polysaccharide mixture in solution and film casting, PVOH. βCD*; cross-linking of the polymer, addition of βCD, and casting of the mixture, PVOH*.CD; and casting of a PVOH film, addition of a βCD/glyoxal solution onto the film, and cross-linking during drying, PVOH.CD*. Characterization studies showed that the PVOH*.CD and PVOH.CD* films provided the best physical characteristics with the lowest release values and the highest barrier properties. As a potential application, materials were tested as potential cholesterol-scavenging films. There was a significant reduction in the cholesterol concentration in milk samples when they were exposed to the materials developed.