DNA markers for eating quality of indica rice in Indonesia

Rice eating quality is considered to be one of the top priorities in determining the agronomical value of rice; thus, the rapid evaluation of eating quality at early breeding generations in breeding programmes for better eating quality is of great importance. In an attempt to develop DNA markers associated with eating quality of indica rice, we used multiple regression analysis to test 54 markers, which were preselected for their possible association with eating quality, using 24 indica varieties with different palatability scores. Of these markers, eighteen markers were found to be significantly associated with palatability according to sensory evaluation. Accordingly, a marker set in the model regression equation with a high R² (0.997) was formulated to estimate indica rice palatability. Validation suggests that markers and the statistical parameters formulated by the equation could be a potential tool to predict the palatability of cooked Indonesian indica rice and could be reliable in developing country‐dependent model equations for eating quality.     

根外施用钙肥对苹果树生育期及产量的影响

作物产品中的钙含量是人类钙营养元素的重要来源，施钙能够提高植物性食品中的含钙量，从而有利于人类健康。若植物新根生长受阻或蒸腾作用减小，作物中钙的含量急剧降低，这样将影响作物的正常生长发育。通过对作物进行根外喷施钙肥，能够快速有效的补充植物对钙元素的需要。本试验通过在苹果的开花期、结果期以及膨大期连续三次叶面喷施不同含量的钙肥，测出喷施含钙量为160g/L钙肥的苹果树的每公顷产量较对照清水的增产5666.6kg，增产率达14.4%，并且方差分析达极显著水平；在喷施含钙量为120g/L的钙肥的苹果树的每公顷产量较对照清水的增产4888.8kg，增产率达12.4%，并且方差分析达显著水平。     

Improved drought tolerance of transgenic Zea mays plants that express the glutamate dehydrogenase gene (gdhA) of E. coli

Genetic modification of nitrogen metabolism via bacterial NADPH- dependent glutamate dehydrogenase (GDH; E.C.4.1.2.1) favorably alters growth and metabolism of C3 plants. The aim of this study was to examine the effect of expression of GDH in the cytoplasmic compartment of Zea mays cells. The gdhA gene from Escherichia coli , that encoded a NADPH-GDH, was ligated to the ubiquitin promoter that incorporated the first intron enhancer and used to transform Z. mays cv. ‘H99’ embryo cultures by biolistics. R0–R3 generations included selfed inbreds, back-crossed inbreds, and hybrids with B73 derivatives. The lines with the highest GDH specific activity produced infertile R0 plants. The highest specific activity of GDH from the fertile Z. mays plants was sufficient to alter phenotypes. Plant damage caused by the phosphinothricin in gluphosinate-type herbicides, glutamine synthetase (GS; EC 6.1.3.2) inhibitors, was less pronounced in Z. mays plants with gdhA pat than in gusA pat plants. Germination and grain biomass production were increased in gdhA transgenic plants in the field during seasons with significant water deficits but not over all locations. Water deficit tolerance under controlled conditions was increased. Crops modified with gdhA may have value in semi-arid locations.     

Breeding system, genetic diversity and clonal structure in the sub-alpine forb Rutidosis leiolepis F. Muell. (Asteraceae)

Genetic markers, controlled pollinations and chromosome analysis were used to examine the breeding system, clonal structure, genetic diversity and cytological complexity of populations of the endangered sub-alpine forb Rutidosis leiolepis. Results show that R. leiolepis: (1) has a strong sporophytic self-incompatibility system; (2) exhibits significant clonality and that the importance of vegetative reproduction increases at higher altitudes; (3) is genetically diverse, but that variation within populations decreases and differentiation among populations increases with altitude; and (4) is diploid with 2n=22 throughout its geographic range. Based on these results, low altitude populations around Cooma and Happy Valley should be made priority areas for in situ conservation in the Species Recovery Plan currently being developed by the New South Wales National Parks and Wildlife Service because they exhibit the most sexual reproduction and highest levels of genetic variation within the species. They may also be demographically more viable in the long term, having larger effective population sizes and less likelihood of mate limitation due to low S allele richness than high altitude populations. Sampling strategies for ex situ conservation should vary from large collections within populations at low altitudes to smaller collections spread across populations at higher altitudes where more of the genetic diversity is partitioned among sites. This should give maximum representation of the species' gene pool for minimum sampling effort.     

Characterization of Royal Gala apple aroma using electronic nose technology-potential maturity indicator

Changes in aroma of apple harvested at four different maturities were measured at harvest and after short-term storage using electronic aroma sensors ("electronic nose") and classical headspace/gas chromatography methods. Stored fruits were also evaluated by a trained sensory panel. Compared with headspace/gas chromatography, the electronic nose was found to be more sensitive ( approximately 40 times) in terms of sample size. The sampling procedure for the electronic nose was much less complex. Using discriminant function analysis, both methods classified the apples tested into groups according to harvest date. After storage, the groupings were more diffuse. Results from sensory testing showed partial separation along the first linear discriminant but did not classify the apple into distinct groups. Important differences between treatments were found for "overall flavor", "acid flavor" intensity, "crispness", "cider/fermented aroma", "vegetative aroma", and "canned pear aroma".     

Chicken model for studying dietary antioxidants reveals that apple (Cox's Orange)/broccoli (Brassica oleracea L. var. italica) stabilizes erythrocytes and reduces oxidation of insoluble muscle proteins and lipids in cooked liver

A chicken model for studying the effects of antioxidants in the diet on oxidative status was set up. Chickens fed a semi-synthetic diet low in antioxidants showed a remarkable decrease in erythrocyte stability toward H(2)O(2) or 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH), but increases in catalase activity in liver, carbonyls in insoluble muscle proteins, and enhanced lipid oxidation in heat-treated liver samples compared to that of conventionally fed chickens. Thus, this chicken model proved to be more susceptible to oxidative changes than conventionally fed chickens, reflecting a low antioxidative defense. Supplementing this low antioxidant diet with 10% apple/broccoli mixture counteracted these changes, except for activity of catalase in the liver and AAPH-induced lysis of erythrocytes. Supplementation with 10% sweet corn only reduced the carbonyl content in insoluble proteins. However, neither low antioxidant diet nor vegetable supplements affected selected antioxidative enzymes or oxidative stability of lipids in heat-treated muscle tissue.     

The effects of fluctuations in atmospheric pressure on landfill gas migration and composition

Measurements of landfill gas emissions from a single site frequently show large variations in chemical composition and magnitude, often on the same time scale as the monitoring interval. These changes are generally ascribed to faulty instrumentation or mysterious alterations in the internal biological processes. This paper demonstrates a simple deterministic physical mechanism able to explain many of these changes, and discusses the implications this has for monitoring strategies. The main conclusions are that the total rate of gas venting depends linearly on the rate of change of the atmospheric pressure, with the stoichiometric variations depending additionally on the physical characteristics and moisture distribution within the site.     

Buckwheat extract inhibits progression of renal failure

Rats subjected to partial resection of the parenchyma showed reduced radical-scavenging activity in the remaining kidney and increased severity of renal tissue lesions. However, in similarly nephrectomized rats given buckwheat extract, the state of oxidative stress improved by restoring the decreased activities of reactive oxygen species-scavenging enzymes such as superoxide dismutase and catalase. The degree of mesangial proliferation, severity of extratubular lesions such as crescents and adhesions, glomerulosclerosis index, and severity of tubular interstitial lesions also improved. In addition, nephrectomized rats given buckwheat extract showed improvement in renal function, as indicated by decreased serum level of creatinine, with a significant decrease in the level of methylguanidine, a uremic toxin produced from creatinine in the presence of hydroxyl radical.     

Characterization and neutralization requirements of two acidic lake sediments

Preparations for neutralization of two acidic lakes in the southwest Adirondacks included determination of base neutralization capacity for sediments as well as the water column. For sediments this involved assessing vertical and horizontal gradients in sediment properties related to sediment-bound acidity. The analyses showed significant variance vertically (depth within the sediment profile) and horizontally (due mainly to depth of overlying water) in both lakes. Base requirements, equivalent to the acidity present 3in 2 cm of sediments ranged between 0.011 and 0.022 kg CaCO₃ m^?3 for the two lakes. Preliminary observations indicate pH³ values and Ca content increased in the surficial sediments of both lakes after treatment.