Golden rice: introgression, breeding, and field evaluation

Considerable progress has been made on the genetic engineering of rice for improved nutritional content involving micronutrients and carotenoid content. Golden Rice, developed by genetic engineering (Agrobacterium and biolistic transformation) was used in rice breeding for the transfer of high-nutritional value to the local rice cultivars. Simultaneously, commercial Asian indica rice cultivars were also developed with expression of high-carotenoid levels. The lines were developed based on POSITECH (PMI) selection system or made marker free by segregating out the marker gene from the gene of interest. Anther culture was used to develop the homozygous stable lines, which could be of much use in further introgress-breeding and in farmer’s field. Enhanced carotenoids levels (up to T3 generation) were observed in a number of lines compared to the T0-T1 seeds which could be due to transgeneration effect of growing under greenhouse versus field conditions. However, a few introgressed lines showed less carotenoid levels than the original lines used in the breeding process. Agronomic performance of introgressed lines, non-transgenic controls, and transgenic golden rice (IR64 and BR29) developed at IRRI showed acceptable and comparable data under identical limited field conditions (screenhouse data). Syngenta generated a new Golden Rice (US cultivar) containing high level of carotenoids grown in the field at Louisiana, USA is expected to be available to the public domain. Incorporation of genes for carotenogenesis in seeds by transgenesis or by introgression did not change any significant agronomic characteristics in rice plants. The ongoing and future study of bioavailability, quality, larger field testing and freedom to operate will ensure the benefit of Golden Rice to the people who need them most.     

Effects of Soil Application of Amino Acids,Ammonium, and Nitrate on Nutrient Accumulation and Growth Characteristics of Sweet Basil

ABSTRACT

The use of organic or reduced form of nitrogen (N) can have various beneficial effects in terms of plant nutrient uptake, metabolism, and environmental issues. In this study, the influence of soil application of reduced N-forms (ammonium, glycine, and glutamine) compared to nitrate and a no fertilizer treatment was evaluated on growth characteristics of sweet basil (Occimum basilicum L.) under a moderate lime soil conditions. The basil growth traits including root and shoot biomass were increased under application of reduced N-forms mainly glycine and glutamine compared to no fertilizer treatment. Application of reduced forms of nitrogen (ammonium, glycine, and glutamine) increased the leaf concentrations of potassium (K), magnesium (Mg), calcium (Ca), iron (Fe) and zinc (Zn), whereas the leaf N concentration was increased by ammonium and nitrate fertilization compared to unfertilized control plants. The results indicate that soil application of reduced N-forms particularly glycine and glutamine is superior to nitrate application.     

Effects of Salinity and Nitrogen on Growth,Contents of Pigments,and Ion Accumulation of a Euhalophyte Suaeda Salsa in an Intertidal Zone and on Saline Inland

The different responses of two populations of Suaeda salsa (Linn.) Pall. (saline seepweed) from an intertidal zone and a saline inland zone to salinity [1 or 500 mM sodium chloride (NaCl)] and nitrogen [N; 0.05, 1, or 10 mM nitrate (NO₃ ^?)‐N] were investigated. Greater NO₃ ^?‐N supply (10 mM) increased shoot dry weight for the two populations of S. salsa, especially for S. salsa from the saline inland zone. Greater NO₃ ^?‐N supply (10 mM) increased the concentrations of chlorophyll and carotenoid in leaves and the NO₃ ^? and potassium (K⁺) concentrations in shoots for both populations. Greater NO₃ ^?‐N supply (10 mM) increased shoot Na⁺ in S. salsa from the intertidal zone. In conclusion, S. salsa from the saline inland zone is more responsive to NO₃ ^?‐N supply than the intertidal population. Greater NO₃ ^?‐N supply can help the species, especially the intertidal population, to grow and to mediate ion homeostasis under high salinity.     

植物类胡萝卜素生物合成及其调控与遗传操作

类胡萝卜素是生物体内通过类异戊二烯途径合成的、自然界广泛存在的一大类天然色素物质的总称。近年来,类胡萝卜素生物合成基因的分离和功能鉴定与有关类胡萝卜素生物合成调控机制研究的新进展,使通过遗传操作调控植物体内类胡萝卜素生物合成途径成为可能。本文主要综述了近年来类胡萝卜素生物合成及其调控研究的进展,并介绍了应用转基因技术改变植物体内类胡萝卜素成分与含量的成功事例。     

基因型和环境对小麦类胡萝卜素含量及其品质性状的影响

为了给小麦类胡萝卜素含量及其相关品质性状的改良提供参考,选用了15个小麦品种作为试验材料,分别在安徽省5个生态区进行区试,测定了小麦全麦粉的类胡萝卜素含量、脂肪氧化酶( LOX )活性、白度等性状。结果表明,15个小麦品种的类胡萝卜素含量及其他被测品质性状在基因型间和环境间的差异均达到极显著水平;类胡萝卜素、蛋白质、湿面筋和淀粉含量的环境变异大于基因型变异,而LOX活性、L值,a值、b值和白度等指标的基因型变异大于环境变异。基因型和环境对小麦品种的类胡萝卜素含量及其他品质性状均有重要影响,基因型与环境互作效应亦不可忽视。     

观赏植物花色基因工程的研究进展

介绍了观赏植物花色素的种类、显色影响因素、类黄酮类色素和类胡萝卜素的生物合成途径以及利用基因工程改变花色的国内外进展．同时简单阐述了花卉基因工程中存在的问题和应用前景。     

Effects of dietary carotenoid on the gut and the gonad of the sea urchin Paracentrotus lividus

Gonad colour, determined by accumulated carotenoids, is an important marketability factor in sea urchin products. In this study, dietary carotenoids were fed to Paracentrotus lividus in prepared diets to test their effects on the sea urchin's gonad colour. All diets had the same basic content of protein, lipid, carbohydrate, ash and energy. Four diets were enriched with: (I) all-trans β-carotene; (II) astaxanthin; (III) zeaxanthin/lutein/β-carotene; and (IV) capsanthin/zeaxanthin/lutein/cryptoxanthin/β-carotene. A fifth diet had Dunaliella bardawil algal powder containing all-trans and 9-cis β-carotene added, and a sixth one was a control diet with no added carotenoids. Sea urchins were fed the control diet (no pigments) for 4 weeks, then the six experimental diets for 8 weeks. Carotenoid concentration in the gut and gonad was determined by tri-dimensional photo-diode array high performance liquid chromatography. Four qualitative colour categories were established: brown, pale yellow, medium-orange, and mango-orange.Gonad development and test diameter increased equally in all diet treatments. Carotenoid profile and concentration in the gut were higher than in the gonad or in the feed. Total carotenoid concentration was four- to ten-fold greater in the gut than in the gonad, and carotenoid profile in the gut was different from that of the diet. Gut and gonad total carotenoids, β-carotene, and echinenone concentration were not dependent on total dietary carotenoid concentration. Total carotenoid and β-carotene concentration in the gut, and total carotenoid and echinenone concentration in the gonad were significantly dependent on dietary β-carotene concentration. The percentage of gonads with acceptable colour was positively correlated with dietary and gut β-carotene concentration. Carotenoids not normally contained in the diet of P. lividus (astaxanthin, capsanthin and capsorbin), did not accumulate in the gonad. Echinenone was found in all gut and gonad samples. Over 90% of the gonads from P. lividus fed Dunaliella algal powder diet developed the optimal mango-orange colour and this diet led to the greatest echinenone concentration.     

宫内伊予柑果实发育期间色泽和色素的变化

 以宫内伊予柑为试材, 对果实发育期间色泽、色素种类及含量, 尤其是类胡萝卜素组分进行了研究。结果表明, 幼果中高含量的叶绿素使果实呈现青绿色, 采前8周起类胡萝卜素开始积累, 采前4周起随叶绿素含量下降黄色得以显现。果实类胡萝卜素主要存在于果皮中, 成熟果实果皮类胡萝卜素含量达囊瓣的16.62倍, 总量占整果的83.62%。用高效液相色谱—二极管阵列检测(HPLC - PDAD) 技术,对采前12周至采收期的果皮类胡萝卜素组成进行了分析, 共分离出类胡萝卜素组分23种, 其中7种得到鉴定。在采收期果皮中, 已鉴定的类胡萝卜素中以β - 隐黄质和玉米黄素较丰富, 占总类胡萝卜素的8.00%和6.78%; β - 胡萝卜素不足总类胡萝卜素的1% , 没有检测出α - 胡萝卜素和番茄红素。果实成熟过程中β - 隐黄质及玉米黄素含量上升, 并伴随α - 胡萝卜素、叶黄质和β - 胡萝卜素含量下降, 暗示类胡萝卜素的β主链合成能力和β环羟化活性急剧增强, 与此同时, 阿朴类胡萝卜素的出现则表明类胡萝卜素的裂解能力随果实成熟而上升。     

Influence of cultivar and site of cultivation on levels of lipophilic and hydrophilic antioxidants in virgin olive oils (Olea Europea L.) and correlations with oxidative stability

Oxidation stability is an important property of olive oil quality and is affected by different antioxidant compounds whose levels may be influenced by cultivar, year and place of production. Polyphenols, tocopherols, carotenoids, chlorophylls and fatty acids levels were correlated to oxidative stability in olive oils from three experiments: cultivar influence (18 cultivars assessed for 4 years in the same place); environmental influence by mesoclimatic (4 cultivars from 17 sites in a single region for 4 years) and macroclimate conditions (3 cultivars from 3 different regions for 3 years). Total polyphenols and saturated on polyunsaturated fatty acids ratio were shown to be the major factors in oil antioxidant stability, according to multivariate regression models. Among the surveyed cultivars, oils from ‘Leccino’ and from three ‘local’, minor cultivars (‘Miniol’, ‘Regina’ and ‘Rossanello’) resulted in higher oxidative stability and oils from cultivars grown in Tuscany (central Italy) showed the highest oxidative stability by comparison with northern and southern regions.