Effect of Different Drying Methods on the Physicochemical Properties and Bioactive Components of Saffron Powder

Plant Foods for Human Nutrition - Saffron is the most expensive spice in the world; so, determining optimum conditions for its processing is crucial. The most important processing stage of saffron...     

Evaluation of genetic diversity of Aegilops tauschii accessions using morphological characters

A collection of sixty-three accessions of Ae. tauschii belonging to different eco-geographical regions were used to evaluate its genetic diversity by 15 morphological characters. The data recorded were analyzed on all accessions using multivariate analyses. Principal component analysis (PCA) indicated that first six principal components with eigenvalues more than 1 explained 77.2% of the variability amongst accessions. Through cluster analysis according to Euclidian distance and UPGMA method, accessions divided into three groups. Knowledge of genetic diversity in Aegilops species provides different levels of information which is important in the management of germplasm resources.     

New terpolymers from n-butyl acrylate,glycidyl methacrylate and tetrahydrofurfuryl acrylate: Synthesis,characterisation and estimation of reactivity ratios

Development and practical application of multicomponent copolymerisation systems, such as terpolymerisation, is an on-going process because even a small addition of a particular comonomer may have a significant impact on the desired property. Commonly, three separate pairs of binary polymerisation experiments are carried out to obtain monomer reactivity ratios (MRR) values that relates to the ternary polymerisation reactions. However, the reaction conditions in each binary system may not be representative of the whole ternary system. The error-in-variables model (EVM) method is a relatively recent statistical approach to solving multi-response parameter estimation problems, with the advantage that all MRR parameters can be directly estimated from terpolymerisation data. New ternary copolymers derived from n-butyl acrylate (nBA), glycidyl methacrylate (GMA) and tetrahydrofurfuryl acrylate (THFA) were synthesised in solution at 70±1 °C in the presence of benzoyl peroxide (BPO) as a free radical initiator. The terpolymers were characterised by ¹H NMR, ¹³C NMR and FTIR spectroscopic techniques. The terpolymer compositions were determined using ¹H NMR analysis. The polydispersities of the terpolymers with values between 1.66 and 1.85 suggest a strong tendency for chain termination by disproportionation. The glass transition temperatures of the terpolymers are found to be between those of the corresponding homopolymers and relative to their content. Increase in the nBA or THFA contents and decrease in the GMA content in terpolymers results in a decrease in the glass transition temperatures. The determination of MRR for the ternary system was obtained by employing the EVM model. Experimental terpolymerisation data agree well with calculations based on the Alfrey-Goldfinger equation and the unitary and binary azeotropes were calculated.     

Variation in virulence and resistance in the bean-bean rust pathosystem in Ecuador

Twenty two Uromyces appendiculatus isolates were tested on 20 differential and 25 Ecuadorian Phaseolus vulgaris cultivars in the seedling stage. Based on the infection types 20 races could be discerned. The Ecuadorian cultivars differed greatly in their reaction to the isolates, from resistant to only one isolate (`Red Small Garden') to resistant to all isolates (’G2333‘). The isolates showed a wide range of virulence to the Ecuadorian cultivars, from virulent to only two cultivars (isolate 13) to virulent to 21 cultivars (isolates 5 and 23). Seven cultivars with a basically susceptible infection type appeared to differ greatly in quantitative resistance when tested in three consecutive crop cycles. The disease severities in percentage leaf area affected averaged over the three cycles ranged between 83.9% for ‘Red Small Garden’ and 13.1% for ‘INIAP-414’. Race-specific resistance does not seem an advisable breeding strategy, but the quantitative resistance offers a good alternative.     

Synthesis and characterization of new copolymers from glycidyl methacrylate and tetrahydrofurfuryl acrylate: Determination of reactivity ratios

The new copolymers from different feed compositions of glycidyl methacrylate (GMA) and tetrahydrofurfuryl acrylate (THFA) were synthesized using free radical polymerization in toluene at 70±1 °C using benzoyl peroxide (BPO) as initiator. The polymers were characterized by ¹H NMR, ¹³C NMR and FTIR spectroscopic techniques. The polydispersities of the copolymers suggest a strong tendency for chain termination by disproportionation. The glass transition temperature of the copolymers increases with increase in GMA content. The thermal stability of the copolymers increases with increase in THFA content. The copolymer compositions were determined using ¹H NMR analysis. Reactivity ratios for GMA and THFA as determined by the Mao-Huglin method were r₁=0.379 and r₂=0.266. The results showed that all these copolymerizations are strictly linear systems describable by the Mayo-Lewis equation based on the terminal model and that accurate reactivity ratio data can be obtained.     

Molecular genetic diversity and population structure of Iranian honey bee (Apis mellifera meda) populations: implications for breeding and conservation

Journal of Plant Diseases and Protection - The honey bee (Apis mellifera), as one of the most important pollinating insects, plays a critical role in biodiversity conservation and global food...     

Virulence of wheat yellow rust races and resistance genes of wheat cultivars in Ecuador

Virulence factors of the yellow rust, Puccinia striiformis, populations in bread wheat were studied in Ecuador between 1973 and 2004. The number of virulence factors has increased markedly from very few in the early seventies to 16 at the end of the 90s. Isolates belonging to race 0E0 seem to be the ancestor of a rapid virulence evolution of yellow rust in Ecuador. This evolution can be explained by a single step mutation pattern. Virulence to the resistance genes Yr1, Yr2, Yr2+, Yr3V, Yr3ND, Yr4+, Yr6, Yr6+, Yr7, Yr7+, Yr9, Yr9+, Yr11, Yr12, Yr18, Yr24, Yr26 and those in the cultivars Carstens V (YrCV) Strubes Dickkopf (YrSD), Suwon92/Omar (YrSU), Spaldings Prolific (YrSP), Anza (YrA+) and Selkirk (YrSK). was identified. Virulence to Yr5, Yr8, Yr10, and Yr15 was not found. Postulation of resistance genes at the seedling stage of 14 Ecuadorian wheat cultivars indicated that these cultivars carry alone or in combinations the resistance factors Yr1, Yr2, Yr3, Yr6, Yr9 and/or other undesignated resistance factors. Yellow rust evolution in Ecuador has been associated with deployment of these resistance genes. None of these deployed Yr resistance genes are effective to the present yellow rust population in Ecuador.     

Farmers’ participation and breeding for durable disease resistance in the Andean region

In the Andean region, the Preduza project and its partners combined breeding for durable disease resistance using locally adapted cultivars and farmer participatory methods. The approach taken resembles participatory variety selection (PVS). Farmers participated in the selection of advanced materials, rather than finished cultivars. This paper describes this approach and reports experiences with farmers–breeders collaboration. As breeders involved farmers as participants, they learned more about the most important criteria of male and female farmers for preferred cultivars in the marginal environments of Andean cropping systems. This approach encouraged the use of locally adapted cultivars (often landraces), made the breeders less dependent on foreign materials, and has resulted in selection and development of new wheat, barley, common bean, quinoa, potato and maize cultivars. Breeding programmes based on crossing locally adapted cultivars followed by selection by the breeders in the early phases of the breeding programmes and by participatory selection with the farmers in the more advanced stages of the breeding programmes appeared successful. It became clear that breeders must be well acquainted with the farmer preferences such as the requirements for specific agronomic, storage, processing and marketing traits. Over a period of five years the centralized formal breeding approach predominantly based on material produced by the international institutes was replaced by decentralized breeding approaches based largely on local germplasm with extensive farmer participation.     

Does interplot interference affect the screening of wheat for yellow rust resistance?

Summary In small plots, adjacent to one another, a representational error can be expected when screening for quantitative forms of resistance to airborne pathogens. The representational error or interplot interference may occur as an underestimation of the level of resistance and/or as an error in the ranking of the entries tested.Four experiments were carried out with wheat (Triticum aestivum) exposed to yellow rust (Puccinia striiformis), three in Kenya, one in Mexico (exp. III).In experiment I 57 entries were compared in an unreplicated trial with three adjacent and one isolated plot situation. The range in the standard deviation of and the ranking order for disease severity (DS) between the 57 entries were the same for all plot situations at all observation dates.In experiment II nine entries from experiment I, representing a wide range of quantitative resistance and having a similar heading date, were compared in adjacent plots consisting of two rows of 10 m in eight replicates and isolated plots of one, six and ten rows of 4 m in three replicates. The range in the standard deviation of and the ranking order for DS between the entries were very similar for the four plot situations.The 10 entries in experiment III differed from those in experiment II, but represented a similar wide range of resistance. Three adjacent plot situations of 0.9×0.5 m, 0.9×2.0 m and 2.7×2.0 m, respectively, were compared with one isolated one with plots of 2.7×2.0 m. The ranking order was not affected, the range in and the standard deviation of the DS in the isolated plots were slightly larger than in the adjacent plots.In experiment IV two mixtures of two entries each were made. Per mixture one entry was fairly resistant (R) the other rather susceptible (S). Within each mixture the entries had a similar heading date. The ratios of the R:S mixtures were 0:100, 50:50, 67:33, 75:25, 82:18 and 100:0. The DS of each entry was the same as its DS in monoculture irrespective of the mixture ratio. There was no mixture effect on DS.The three experiments in Kenya gave no indication of any interplot interference occurring. In Mexico there was a very slight underestimation of the resistance in adjacent plots. The ranking order was always the same irrespective of the test plot situation. The screening of wheat for yellow rust resistance in small adjacent plots is representative for the farmers fields. This is contrary to what has been found in other windborne pathosystems such as barley-barley leaf rust (strong under estimation of resistance), barley-powdery mildew (some under estimation of resistance and different ranking order) and durum wheat-stem rust (fair under estimation of resistance).