Stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the most destructive diseases of wheat worldwide. Growing resistant cultivars is the most effective approach to control the disease, but only a few genes confer effective all-stage resistance against the current populations of the pathogen worldwide. It is urgent to identify new genes for diversifying sources of resistance genes and for pyramiding genes for different types of resistance in order to achieve high levels of durable resistance for sustainable control of stripe rust. The common spring wheat genotype 'PI 181434', originally from Afghanistan, was resistant in all greenhouse and field tests in our previous studies. To identify the resistance gene(s) PI 181434 was crossed with susceptible genotype 'Avocet Susceptible'. Adult plants of 103 F(2) progeny were tested in the field under the natural infection of P. striiformis f. sp. tritici. Seedlings of the parents, F(2) and F(3) were tested with races PST-100 and PST-127 of the pathogen under controlled greenhouse conditions. The genetic study showed that PI 181434 has a single dominant gene conferring all-stage resistance. Resistance gene analog polymorphism (RGAP) and simple sequence repeat (SSR) techniques were used to identify molecular markers linked to the gene. A linkage map of 8 RGAP and 2 SSR markers was constructed for the gene using data from the 103 F(2) plants and their derived F(3) lines tested in the greenhouse. Amplification of the complete set of nulli-tetrasomic lines and selected ditelosomic lines of Chinese Spring with an RGAP marker and the two SSR markers mapped the gene on the long arm of chromosome 3D. Because it is the first gene for stripe rust resistance mapped on chromosome 3DL and different from all previously named Yr genes, the gene in PI 181434 was designated Yr45. Polymorphism rates of the two closest flanking markers, Xwgp115 and Xwgp118, in 45 wheat genotypes were 73.3 and 82.2%, respectively. Single nucleotide polymorphisms (SNPs) were identified in the eight wheat genotypes sharing both flanking markers. The RGAP markers and potential SNP markers should be useful in incorporating the gene into wheat cultivars and in pyramiding it with other genes for durable resistance.

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Aqueous extraction is a promising green alternative to hexane extraction. This study used a salt effect-aided aqueous extraction process (AEP-SE) for extracting Camellia oleifera seed oil (COSO) to improve oil extractability and avoid emulsification in the aqueous system. The highest oil extractability rate of 88.8% was obtained under 1.48 mol L^–1 sodium carbonate, a solution-to-flour ratio of 3.85, and 3.23h of extraction time with the quality of the aqueous system-extracted oil being similar to those of a commercial sample of COSO and hexane-extracted oil in terms of color, iodine value and saponifcation value, although its moisture content was higher. Furthermore, the free fatty acid content of the aqueous system-extracted oil was lower than that of the solvent-extracted oil. The values of the inibihitory concentration at 50% of oil obtained by AEP-SE and organic solvent extraction as measured by DPPH scavenging activity essay, were 2.27 mg/mL and 3.31 mg/mL. AEP-SE is therefore a promising environmentally friendly method for the large-scale preparation of COSO.

La extracción acuosa es una alternativa verde muy prometedora a la extracción con hexano. En este estudio se utilizó como ayuda en el proceso de extracción acuosa (AEP-SE) el efecto de una sal para la extracción de aceite de semilla de Camellia oleifera (COSO) para mejorar la extractabilidad y evitar la formación de emulsiones en el sistema acuoso. La mayor velocidad de extracción de aceite, 88,8%, se obtuvo con una concentración de carbonato de sodio de 1,48 mol L^–1, una relación de solución a la harina de 3,85, y 3.23h de tiempo de extracción, con una calidad del aceite extraído con el sistema acuoso similares a los de una muestra comercial de COSO extraida con hexano, en términos de índice de yodo, de color, y de índice de saponificación, aunque su contenido en humedad fue mayor. Además, el contenido de acidez libre del aceite extraido con el sistema acuoso fué menor que la del aceite extraído con disolvente. Los valores de la concentración inibihitoria al 50% del aceite obtenido por el AEP-SE y extracción con disolvente orgánico, medido por el ensayo de DPPH actividad de barrido, fueron 2,27 mg mL_–1 y 3,31 mg mL_–1. Por lo tanto, AEP-SE es un método favorable al medio ambiente, prometedor para la preparación a gran escala de COSO

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