Genetic diversity and erosion in lima bean (Phaseolus lunatus L.) in Northeast Brazil

Genetic Resources and Crop Evolution - Lima bean (Phaseolus lunatus L.) is a crop that stands out for its economic and social importance throughout the world, including in Northeast Brazil....     

Application of comprehensive two-dimensional liquid chromatography to elucidate the native carotenoid composition in red orange essential oil

In the present work, the ability of a LC x LC-DAD/APCI-MS method developed at this laboratory to identify the native composition of carotenoid in an extremely complex matrix such as red orange essential oil was demonstrated. To carry out this task, two independent and orthogonal separation mechanisms were coupled through a 10-port switching valve that simultaneously collected the eluent from a microbore cyano column used as the first dimension in normal phase mode and injected it to a conventional reversed phase monolithic C(18) column in the second dimension separation. By using this novel analytical technique together with the use of DAD and APCI-MS detectors it was possible to identify in the sample, without the need of any pretreatment, 40 different carotenoids. Among them, 16 carotenoid monoesters were identified, mainly beta-cryptoxanthin palmitate (C(16:0)), myristate (C(14:0)), and laureate (C(12:0)) as well as several lutein, violaxanthin, antheraxanthin, and luteoxanthin monoesters. Moreover, 21 carotenoid diesters composed by several antheraxanthin, luteoxanthin, violaxanthin, and auroxanthin diesters were found in the native carotenoid composition of the orange oil. The main carotenoid diesters were the laureate palmitate (C(12:0), C(16:0)), myristate palmitate (C(14:0), C(16:0)), and dipalmitate (C(16:0), C(16:0)) diesters, although other diesters were also identified. Besides, two different free carotenes, zeta-carotene and phytofluene, and a xanthophyll, lutein, were also determined. To the authors' knowledge, this is the first time that carotenoid diesters are described and identified in orange essential oil. Likewise, it has been demonstrated that the LC x LC approach proposed in this study is capable of coping with the direct analysis and identification of a complex natural source of carotenoids such as the orange.     

A cross-sectional study of swine influenza in intensive and extensive farms in the northeastern region of the state of São Paulo,Brazil

Swine influenza (SI) is a seasonal infectious disease highly important to the world pig industry. Loss of daily weight gain, increased costs for the prevention and treatment of secondary infections are the main economic losses associated with the presence of this disease. However, some epidemiological features of SI remain quite unclear. This study focused on assessing the prevalence of swine influenza virus (SIV) infection in intensive and extensive pig herds and associating risk factors. A set of 601 blood samples of five intensive farrow-to-finish farms and 361 blood samples from 56 extensive farms were analyzed using an indirect ELISA kit CIVTEST SUIS INFLUENZA®, Hipra (Amer, Spain), in order to detect anti-SIV antibodies. In total, 24.13 % of samples from intensive herds were positive, while no positive samples were detected in extensive rearing herds. Sow and weaning piglets had the highest prevalence values. In the intensive rearing system, occurrence of reproductive disorders and exposure to recently introduced animals were positively associated with the disease occurrence in swine herds. The findings highlight the importance of sows in the epidemiology of the disease and bring information about risk factors involved in the occurrence of swine influenza in intensive herds.     

Leaching behaviour of a sandy soil amended with natural and NH4+ and K+ saturated clinoptilolite and chabazite

Using saturated or enriched zeolites as slow release fertilizers (SRFs) is considered as an environmental-friendly strategy to enhance use of macronutrients in sandy soils. In this paper, two natural zeolites, clinoptilolite (CLI) and chabazite (CHA) were used as mineral precursors to prepare NH₄⁺/K⁺ saturated clinoptilolite (NH₄⁺/K⁺-CLI) and chabazite (NH₄⁺/K⁺-CHA) as zeolitic nutrient sources (ZNSs). Comparison between the nutrient retention capabilities of these ZNSs was one of the main objectives of this study. The NH₄⁺/K⁺-CLI and NH₄⁺/K⁺-CHA were prepared by soaking the zeolites in NH₄Cl and KCl solutions, respectively. Leaching tests were performed on a sandy soil amended with chemical fertilizers (CFs), NH₄⁺/K⁺-CLI and NH₄⁺/K⁺-CHA to evaluate the leaching properties of them. The results indicated that approximately 84% and 88% of the NH₄⁺ and K⁺ of soils fertilized with CFs were lost during the experiment, respectively. While, the NH₄⁺ and K⁺ losses from soils amended with NH₄⁺/K⁺-CLI and NH₄⁺/K⁺-CHA were 29%, 23%, and 14%, 24%, respectively. Despite of drastic changes in leaching behavior of CFs, nutrient losses from ZNSs were more uniform during the experiments. No significant difference was found between the two studied zeolites on reduction of K⁺ loss. However, CHA was more effective in preventing NH₄⁺ loss during leaching.     

Reproductive behaviour of tetraploid alfalfa plants obtained by unilateral and bilateral sexual polyploidization

The objective of the present study was to evaluate the fertility of tetraploid plants obtained from diploid mutants that produced 2n gametes via bilateral (BSP) and unilateral sexual polyploidization (USP) schemes. Controlled matings between selected plants from BSP and USP were carried out according to a complete diallel. The level of male and female fertility of each plant was estimated within full-sib, half-sib and non-inbred crosses. Crosses with unrelated self-fertile and male-sterile testers were also performed. Pollen size and stainability were determined by acetocarmine staining. The number of ovules per ovary was counted and the callose deposition within ovules examined to evaluate embryo sac fecundity. Cross-fertility was generally much higher for USP than BSP plants (on average, 0.3 vs. 0.03 seeds per flower pollinated). Both male and female fertility were inversely related to the inbreeding level of cross combinations. The in vitro pollen germinability was positively correlated to male fertility of BSP plants. The level of in vivo embryo sac sterility was not correlated to female fertility in either BSP or USP plants. Female fertility was restored in both BSP and USP groups when plants were crossed with unrelated tetraploid testers. Male fertility also increased in USP plants but remained rather low in the BSP plants. Scaling up the ploidy level by means of 2n gamete union resulted in tetraploid plants with low fertility. In particular, the BSP process yielded virtually self-sterile and highly cross-sterile plants. The well documented positive effect of sexual tetraploidization on forage yield was accompanied by worsening of fertility traits. This revised version was published online in July 2006 with corrections to the Cover Date.     

Modelling the biomass yield and the impact of seabream mariculture in the Adriatic and Tyrrhenian Seas (Italy)

An individual-based model for Sparus aurata was developed, taking into account the effects on the growth rate of water temperature, food availability and diet composition. The model was identified on the basis of the recent literature regarding the physiological ecology of this species. It was subsequently calibrated and validated by using original field data collected at two Italian fish farms located, respectively, in the Adriatic and Tyrrhenian Seas. The mass budget of uneaten food and faeces was computed using the model at each farm: the optimal ingestion rate of a fish was computed based on its wet weight and the temperature of the water, while the faeces estimation considered the different digestibility of lipids, carbohydrates and proteins in the diet. From an applied perspective, the future use of this growth model in relation to mariculture site selection and monitoring might typically be to estimate both the yield and the amount of uneaten food and faeces discharged from a fish cage. This second output represents a useful input for deposition models which are routinely used in the field of mariculture monitoring by different EU countries. The integration of growth and deposition models in a single system could provide a useful tool for the site-selection and monitoring of finfish mariculture operations in Mediterranean environments.     

意大利杏遗传育种研究现状

意大利地处地中海沿岸,是杏传播途径中一个重要的人工驯化区域,也是欧洲最大的杏生产国。该文根据与意大利多年的学术交流,对意大利及部分其他欧洲国家的杏育种研究现状进行了较为详细的介绍,以期为国内杏育种工作提供借鉴。