Tuber quality and soft rot resistance of hybrids betweenSolarium tuberosum and the incongruent wild relativeS. commersonii

Tetraploid BC₃ hybrids between sexually incompatible speciesSolanum commersonii andS. tuberosum were characterized for tuber quality (stolon length, tuber eye depth, chipping color from 3-month storage at 5 C, and specific gravity) and soft rot resistance traits. For all analysed morphological traits, except stolon length, genotypes resembled theS. tuberosum phenotype. On average, the specific gravity of selected genotypes was quite high (1.087), and 12 of them had a value >1.090. As for chipprocessing ability, 4.8% of genotypes chipped well directly from cold storage, and 14.3% after reconditioning. All but one of these genotypes also possessed a high specific gravity of tubers. Variability was found for resistance toErwinia carotovora subsp.carotovora. In particular, 24% of hybrids had a rotted area diameter ≤ 4 mm and were classified as resistant. The average percentage ofcommersonii-specific markers still present in the BC₃ hybrids was 22%, ranging from 9% to 37%. Genotypes combining good qualitative tuber traits with a wild genome content lower than the average value of the population were selected for further breeding efforts. The importance of molecular-assisted selection is discussed.     

Proteins of some legumes with reference to environmental factors and nutritional value

Storage globulins contribute 80–90% of the seed protein of many legumes and consist principally of two proteins called vicilin and legumin in peas. The relative proportions of the two proteins has been shown to differ in different legumes by gel-electrophoresis. The essential amino acid composition of vicilin and legumin ofPisum andVicia differ and the possible significance of these findings to screening strategies for improved legume programmes was discussed.Cowpeas were grown in growth cabinets under standard environmental conditions. Seeds were shown to have the same percentage nitrogen and sulphur on a dry-weight basis, irrespective of the position of the pod on the plant, indicating that legume seeds may have a conservative biochemistry.Paper presented at the conference of the International Association for Quality Research on food Plants (CIQ) held in common with the Deutsche Gesellschaft für Qualitätsforschung (Pflanzliche Nahrungsmittel) e.V. (DGQ) in Berlin on 6th October 1972     

Multiplication ofPseudomonas solanacearum in resistant potato plants and the establishment of latent infections

When 1-mo-old plants of a wilt-resistant clone ofSolanum phureja (1386.15) were stem-inoculated with three strains ofPseudomonas solanacearum (K60, S123, and S206), the bacteria multiplied rapidly at the point of inoculation and then moved in the vascular system to other parts of the stem. Resistant plants showed a remarkable ability to support relatively high populations of the bacterium in the absence of disease symptoms. Although multiplication in this resistant clone was substantially less than in susceptible Russet Burbank potato plants, large numbers of bacteria (up to 624 × 10⁴ cells of K60 per 5-cm stem segment) reached the base of the stem of plants maintained at high temperature (28°C) for 20 days after stem inoculation. From the base of the stem, the bacteria moved rapidly into the roots and tubers. Strains ofP. solanacearum differed in their ability to cause latent tuber infection in different resistant potato clones. When 11S.phureja ×S. tuberosum hybrids were stem-inoculated, maintained at 28°C for 3 wk and then grown to maturity at 20°C., most of the clones yielded tubers infected by one or more strains. The race 1 strain (K60) was the most infectious; 53.8% of all tubers harvested from all plants inoculated with this isolate carried latent infections. Because one clone (BR 53.1) never yielded infected tubers, there appear to be genetic factors which may be useful in breeding programs aimed at eliminating latent tuber infection.     

Spongionella Secondary Metabolites Protect Mitochondrial Function in Cortical Neurons against Oxidative Stress

The marine habitat provides a large number of structurally-diverse bioactive compounds for drug development. Marine sponges have been studied over many years and are found to be a rich source of these bioactive chemicals. This study is focused on the evaluation of the activity of six diterpene derivatives isolated from Spongionella sp. on mitochondrial function using an oxidative in vitro stress model. The test compounds include the Gracilins (A, H, K, J and L) and tetrahydroaplysulphurin-1. Compounds were co-incubated with hydrogen peroxide for 12 hours to determine their protective capacities and their effect on markers of apoptosis and Nrf2/ARE pathways was evaluated. Results conclude that Gracilins preserve neurons against oxidative damage, and that in particular, tetrahydroaplysulphurin-1 shows a complete neuroprotective activity. Oxidative stress is linked to mitochondrial dysfunction and consequently to neurodegenerative disorders like Parkinson and Alzheimer diseases, Friedreich ataxia or Amyotrophic lateral sclerosis. This neuroprotection against oxidation conditions suggest that these metabolites could be interesting lead candidates in drug development for neurodegenerative diseases.     

Mediterranean diet in relation to body mass index and waist-to-hip ratio

OBJECTIVE: The Mediterranean diet is rich in fat and starch, and hence may be related to overweight. We therefore investigated the relationship between adherence to a Mediterranean diet and body mass index (BMI) and waist-to-hip ratio (WHR). DESIGN AND SETTING: Data were obtained from the control group of a network of case-control studies on cancer conducted in major teaching and general hospitals in four Italian areas between 1991 and 2002. An interviewer-administered validated 78-item food-frequency questionnaire was used to obtain information on the subjects' habitual diet. Information on socio-economic factors, lifestyle habits and anthropometric measures was also collected. A Mediterranean diet score (MDS) was derived on the basis of eight characteristics of the Mediterranean diet. SUBJECTS: Subjects were 6619 patients (3090 men, 3529 women) admitted to hospital for a wide spectrum of acute, non-neoplastic conditions, unrelated to known risk factors for cancer and long-term modifications of diet. RESULTS: In multiple linear regression models adjusted for age, study centre, education, tobacco smoking, occupational physical activity and total energy intake, the MDS was not related to BMI (beta = 0.05 for men and -0.04 for women) or WHR (beta = 0.000 and 0.001, respectively) in both sexes. CONCLUSIONS: Adherence to the major characteristics of the Mediterranean diet is unrelated to BMI and WHR, confirming previous data from Greece and Spain.     

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.     

Effect of micro-oxygenation on color and anthocyanin-related compounds of wines with different phenolic contents

Several factors may affect the results obtained when micro-oxygenation is applied to red wines, the most important being the moment of application, the doses of oxygen, and the wine phenolic characteristics. In this study, three red wines, made from Vitis vinifera var. Monastrell (2005 vintage) and with different phenolic characteristics, were micro-oxygenated to determine as to how this technique affected the formation of new pigments in the wines and their chromatic characteristics. The results indicated that the different wines were differently affected by micro-oxygenation. In general, the micro-oxygenated wines had a higher percentage of new anthocyanin-derived pigments, being that this formation is more favored in the wines with the highest total phenol content. These compounds, in turn, significantly increased the wine color intensity. The wine with the lowest phenolic content was less influenced by micro-oxygenation, and the observed evolution in the degree of polymerization of tannins suggested that it might have suffered overoxygenation.     

Nitrous oxide emissions from soil during soybean [(Glycine max (L.) Merrill] crop phenological stages and stubbles decomposition period

The purpose of this study was to evaluate, during the phenological stages of inoculated soybean crop [Glycine max (L.) Merrill], the effect of different N fertilization levels and inoculation with Bradyrhizobium japonicum on N₂O emissions from the soil. Gas emissions were evaluated at field conditions by the static-chamber method. Nitrogen fertilization increased N₂O emissions significantly (P < 0.05). The variable that best explained cumulative N₂O emissions during the whole soybean growing season was the soil nitrate level (r ² = 0.1899; P = 0.0231). Soil moisture presented a greater control on N₂O emissions between the grain-filling period and the crop commercial maturity (r ² = 0.5361; P < 0.0001), which coincided with a positive balance of the available soil N, as a consequence of the decrease in crop requirements and root and nodular decomposition. Only soil soluble carbon (r ² = 0.29; P = 0.019) and moisture (r ² = 0.24; P = 0.039) were correlated with N₂O emissions during the residue decomposition period. The relationship between soil variables and N₂O emissions depended on crop phenological or stubbles decomposition stages.