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1.
栽培大麦辐射敏感性与进化的关系   总被引:1,自引:0,他引:1  
大麦幼苗组织的过氧化物酶同工酶有3个酶带区,8条酶带。辐照后,在偏负极端出现一个新的酶带区,增加1—3条酶带。辐射剂量效应可用线性回归方程Y=A+BX拟合。大麦品种的过氧化物酶同工酶变化与辐射敏感性有关,与进化类型直接相关。协方差分析表明,裸大麦对辐射的敏感性显著高于皮大麦,四棱和六棱大麦则显著高于二棱大麦。据此可以认为,在进化上属原始类型的品种,辐射敏感性较低。  相似文献   

2.
研究了10个不同地理种源的小桐子种子对60Coγ射线照射的敏感性。结果表明,辐射剂量与出苗率呈负相关,且不同剂量处理间的相对出苗率差异达显著或极显著水平,线性回归方程的相关系数为-0.89~-0.96,其半致死剂量为127~184Gy。根据半致死剂量可将10个不同地理种源的小桐子划分为辐射敏感型、辐射中间型和辐射迟钝型,其中贵州贞丰鲁容种源(141Gy)和海南乐东莺歌海种源(127Gy)为辐射迟钝型;云南元江种源(184 Gy)为辐射敏感型;其余7个种源为辐射中间型。本研究可为创制小桐子新种质提供重要试验基础。  相似文献   

3.
不同小麦品种(系)对Ar+注入的敏感性   总被引:1,自引:0,他引:1  
本文就不同小麦品种(系)对Ar+注入的敏感性进行了研究。研究结果表明:6×1016Ar+cm2注入对参试的21个品种(系)的存活率影响可分为5种类型:极敏感型、敏感型、过渡型、迟钝型和极迟钝型;Ar+注入对高水肥型、中水肥型和旱地型小麦品种(系)的敏感性依次为高水肥型>中水肥型>旱地型。本项研究可为Ar+注入不同小麦品种(系)发生诱变的半致死剂量提供实验依据。  相似文献   

4.
辐射对果树花粉发芽率及远缘杂交亲和性的影响   总被引:3,自引:0,他引:3  
李靖  尚霄丽  张建鹏 《核农学报》2006,20(5):395-397
本文研究了不同剂量的60Coγ射线和紫外线辐照对帚型山桃、凯特杏、黑宝石李3种果树花粉后其发芽率及远缘杂交坐果率的影响。结果表明,经60Coγ射线和紫外线照射后,3种果树花粉的发芽率与对照相比都明显降低。3种果树花粉的辐射敏感性有明显差异,其中黑宝石李花粉最敏感,花粉发芽率降低最明显;帚型山桃次之;凯特杏的花粉最不敏感。辐照后的低花粉发芽率降低了远缘杂交的坐果率。  相似文献   

5.
~(60)Coγ射线诱发梨的短枝型变异的探讨   总被引:3,自引:0,他引:3  
本文对苹果梨、朝鲜洋梨辐射营养后代的短枝型变异进行了研究。研究结果表明:辐射有利于培育短枝型品种。在本试验范围内,辐射处理均有不同程度的矮化,而且与对照差异极显著。朝鲜洋梨较苹果梨对辐射处理更敏感。采用辐射诱变矮化型品种,可在V_1代直接进行选择。  相似文献   

6.
施巾帼  张伯林 《核农学报》1990,4(4):193-198
小麦合子期不同阶段的辐射敏感性有明显差异,敏感高峰出现在授粉后11—13小时。γ射线辐照杂合子可获得较高突变率,F_2M_2总突变频率比辐照干种子提高约2.6倍,有益突变频率提高37.5%,而且变异谱较宽。合子期内不同阶段的辐射敏感性与突变频率有紧密的对应关系,合子敏感期是诱变的适宜时期。胚培养有效地提高了F_1M_1的幼苗成活率。  相似文献   

7.
大豆品种间辐射敏感性差异机制的研究   总被引:1,自引:0,他引:1  
袁玉春 《核农学报》1990,4(2):71-74
用60_Coγ射线辐照13个大豆品种的种子表明,不同品种大豆的辐射敏感性存在明显差异。应用3~H-TdR掺入法研究受辐照种子浸种初期的DNA合成情况表明,受辐照的大豆种胚出现非S期DNA合成,即修复合成。品种间辐射敏感性差异与DNA修复合成有关,辐射敏感性高的品种DNA修复合成能力弱,辐射敏感性低的品种DNA修复合成能力强。  相似文献   

8.
选用我国西北的主要牧草苜蓿、少打旺、草木樨、三叶草、小冠花及偃麦草等96个品种,用^60Coγ射线照射种子,测定出苗率。辐照剂量与出苗率的相关关系分析表明,出苗率与剂量之间呈显著、极显著的负相关,出苗率随辐照剂量的增加而降低。计算出各品种的半致死剂量,并按射敏感性将牧草品种划分为敏感型、中间型和迟钝型三类。其中敏感型品种14个(含禾本科牧草品种10个),占总数的14.59%;迟钝型品种11个(含上  相似文献   

9.
同步辐射(软X射线)对水稻的细胞学效应研究   总被引:7,自引:2,他引:5  
王彩莲  陈秋方  金卫 《核农学报》2000,14(3):141-144
对不同剂量的同步辐射 (软X射线 )辐照水稻种子 ,研究其细胞学效应。结果表明 ,软X射线同步辐射处理后 ,在水稻根尖细胞内可诱发各类染色体结构变异。 3个品种的细胞染色体畸变率随照射剂量的增加而提高 ,有丝分裂指数明显下降。同步辐射的细胞学效应与γ射线相似。 3个品种的辐射敏感性从高至低的顺序为加育2 93 >舟 90 3 >浙 73 3  相似文献   

10.
为解析小麦叶片出生与小穗原基分化的同步关系,为营养器官生长和幼穗分化的协调发展、苗情诊断和培育壮苗提供理论依据,以16个小麦品种为试验材料,采用室内春化处理和田间分期播种的方法,研究春化处理和播期对不同春化发育特性小麦品种叶片出生与壮苗冬前安全穗发育期(二棱期)和护颖分化期对应关系的影响。结果表明,小穗原基分化的叶龄和叶龄余数受播期和春化处理的影响较大,不同播期和春化处理的叶龄指数则较为稳定,不同春化发育特性小麦品种间的叶龄指标差异大于播期和春化处理之间的差异。表明主茎叶龄与小穗原基分化的对应关系受生态因子及栽培条件的影响较大,不宜将叶龄作为冬前壮苗的形态指标,而叶龄指数和小穗原基分化之间存在确定的量化关系,且主要由品种特性决定,可将春性品种以二棱期、半冬性品种以单棱末期或二棱始期进入越冬期的叶龄指数作为壮苗的叶龄指标。  相似文献   

11.
Multilocation testing remains the main tool for understanding varietal responses to the environment. Here, Latvian and Norwegian hull-less and hulled barley varieties were tested in field experiments in Latvia and Norway in order to assess the varieties adaptability across environments (sites). Two Latvian (cv Irbe and cv Kornelija) and one Norwegian hull-less barley variety (cv Pihl) were tested along with one Latvian (cv Rubiola) and one Norwegian hulled barley variety (cv Tyra) under conventional and organic management systems. The grain yield, together with physical and chemical grain parameters were compared, and variety yield and protein stability determined. Overall, grain yield of hull-less barley varieties was significantly lower than for hulled barley varieties regardless of climatic conditions and management system. However, in the organic farming systems this difference between barley types was less pronounced. The hull-less barley varieties cv Pihl and cv Irbe, along with both hulled varieties, had good yield stability across environments and were well adapted to both cropping systems. Hull-less barley varieties tended to contain more protein and β -glucans than hulled barley varieties. Despite being bred for local conditions in Norway and Latvia, our study shows that all the varieties used may be successfully transferred across countries.  相似文献   

12.
Barley has a variety of potential food uses. However, the dark gray color of the final products negatively affects consumer acceptability. We determined the discoloration potential of barley from different classes and genotypes, and evaluated the relationship of barley composition, total polyphenol content, and polyphenol oxidase (PPO) activity with discoloration potential of barley. Barley grains were abraded, milled into flour, and analyzed for composition, total polyphenol content, and PPO activity. Total polyphenol content of abraded barley, expressed as gallic acid %, was lowest in hulled proanthocyanidin‐free barley (0.02–0.04%), followed by hulled proanthocyanidin‐containing barley (0.11–0.18%), and hull‐less barley (0.19–0.26%). PPO activity of abraded kernels ranged from 62.1 units/g in hulled proanthocyanidin‐containing Baronesse to 116.5 units/g in hulled proanthocyanidin‐free CA803803. Dough sheet brightness (L* value) was the best indicator of discoloration potential of barley. Large variation in L* value of dough sheets was observed among different classes and among genotypes within classes. Brightness of dough sheets measured at 24 hr were significantly higher in hulled (65.3–78.1) than in hull‐less (59.0–63.9) barley, and within hulled barley, higher in proanthocyanidin‐free (72.2–78.1) than in proanthocyanidin‐containing (65.3–69.6) barley. Total polyphenol content significantly correlated with the discoloration potential of barley. Protein content and ash content also had a significant negative correlation with discoloration of dough sheets. The results indicated that polyphenol compounds may play a major role in discoloration potential of barley‐based products.  相似文献   

13.
Different barley varieties, consisting of hulled and hull-less types, of normal, waxy, and high amylose starch, as well as two-rowed and six-rowed types, were analyzed for their main proanthocyanidins and bound phenolic acids. Variations in proanthocyanidin and phenolic acid contents were studied in different barley types as well as inter-relationships between the phytochemicals and polysaccharides. The main flavanols found in the analyzed barley varieties were two dimeric as well as four trimeric forms in addition to catechin. The total amount of flavanols ranged from 325 to 527 microg/g of fresh weight of barley flour. No evident associations were found between variations in proanthocyanidin levels and different barley types. The total amount of phenolic acids ranged from 604 to 1346 microg/g of fresh weight of barley flour, with ferulic acid as the dominating acid. The amount of phenolic acids varied according to occurrence or lack of hull, with significantly higher levels in the hulled varieties.  相似文献   

14.
Barley and its products are good sources of antioxidants. This experiment was conducted to examine the classification and concentration of phenolic compounds, proanthocyanidins, and anthocyanins in 127 lines of colored barley. Their relationship with 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity was also examined. Barley was placed into seven groups using the colorimeter: hulled (black 1, black 2, black 3, and purple) and unhulled (black, blue, and purple). The contents of phenolic compounds and anthocyanins were analyzed by using HPLC. The average content of phenolic compounds in unhulled barley groups (268.6 microg/g) was higher than that in hulled (207.0 microg/g) (P > 0.05). The proanthocyanidins content was determined by modified vanillin assay. The average content of proanthocyanidins was significantly higher in purple and blue barley groups compared with black (P < 0.05). The content of anthocyanins varied from 13.0 to 1037.8 microg/g. Purple and blue barley groups contained higher average contents of anthocyanins than black (P < 0.05). The most common anthocyanin in the purple barley groups was cyanidin 3-glucoside, whereas delphinidin 3-glucoside was the most abundant anthocyanin in the blue and black groups. In colored barley, DPPH radical scavenging activity had high positive correlation to the content of phenolic compounds and proanthocyanidins.  相似文献   

15.
Ten different barley varieties grown in one location were studied for their content of tocols, folate, plant sterols, alkylresorcinols, and phenolic acids, as well as dietary fiber components (arabinoxylan and beta-glucan). The samples included hulled and hull-less barley types and types with normal, high-amylose, and waxy starch. The aim was to study the composition of raw materials, and therefore the hulls were not removed from the hulled barleys. A large variation was observed in the contents of all phytochemicals and dietary fibers. Two varieties from the INRA Clermont Ferrand barley program in France (CFL93-149 and CFL98-398) had high content of tocopherols and alkylresorcinols, whereas the variety Dicktoo was highest in dietary fiber content and phenolics. Positive correlations were found between 1000 kernel weight, alkylresorcinols, and tocols, as well as between dietary fiber content and phenolic compounds. The results demonstrate that the levels of phytochemicals in barley can likely be affected by breeding and that the contents of single phytochemicals may easily be adjusted by a right selection of a genotype.  相似文献   

16.
Barley grains contain significant amounts of phenolic compounds that may play a major role in the discoloration of food products. Phenolic acid and proanthocyanidin (PA) composition of 11 barley genotypes were determined, using high-performance liquid chromatography and liquid chromatography-mass spectrometry, and their significance on food discoloration was evaluated. Abraded grains contained 146-410 microg/g of phenolic acids (caffeic, p-coumaric, and ferulic) in hulled barley and 182-282 microg/g in hulless barley. Hulled PA-containing and PA-free genotypes had comparable phenolic acid contents. Catechin and six major barley PAs, including dimeric prodelphinidin B3 and procyandin B3, and four trimers were quantified. PAs were quantified as catechin equivalents (CE). The catechin content was higher in hulless (48-71 microg/g) than in hulled (32-37 microg/g) genotypes. The total PA content of abraded barley grains ranged from 169 to 395microg CE/g in PA-containing hulled and hulless genotypes. Major PAs were prodelphinidin B3 (39-109 microg CE/g) and procyanidin B3 (40-99 microg CE/g). The contents of trimeric PAs including procyanidin C2 ranged from 53 to 151 g CE/g. Discoloration of barley flour dough correlated with the catechin content of abraded grains (r = -0.932, P < 0.001), but not with the content of individual phenolic acids and PAs. Discoloration of barley flour dough was, however, intensified when total PA extracts and catechin or dimeric PA fractions were added into PA-free barley flour. The brightness of dough also decreased when the total PA extract or trimeric PA fraction was added into heat-treated PA-free barley flour. Despite its low concentration, catechin appears to exert the largest influence on the discoloration of barley flour dough among phenolic compounds.  相似文献   

17.
γ射线对钝顶螺旋藻(Spirulina platensis)的生物学效应   总被引:5,自引:1,他引:5  
用Cor线照的常状体群体,率是300krud,是示了100krad以下量可以的生长,用超声波把螺单位死剂量是100krad,致,单隹死剂量是100krad,致死剂量是2krad,在100krad对的细总代中,大细长的细胞系,  相似文献   

18.
Dark discoloration negatively influences the aesthetic properties of barley‐based food products. The effects of abrasion and heat treatment of grains, exclusion of oxygen, and the use of antibrowning agents on the retardation of darkening in barley flour gel or dough were determined in four types of barley, including hulled proanthocyanidin‐containing and hulled proanthocyanidin‐free, hulless regular, and hulless waxy barley. Abrasion by >30% in hulled barley and by >15% in hulless barley significantly increased the brightness (L*) of barley flour dough by 0.1–7.1. Steam heating of abraded grains also significantly increased the L* of barley flour gels by 1.8–3.4. Ascorbic acid at 1,500 ppm was most effective for retarding discoloration of barley flour dough, followed by 50 ppm of 4‐hexylresorcinol, which is an enzyme competitive inhibitor. The discoloration of barley flour dough was also effectively reduced by storing the dough sheets at 4°C under nitrogen gas to exclude oxygen or under anaerobic conditions at 20°C. Discoloration of barley‐based food products may be effectively controlled by selecting genotypes with low discoloration development such as proanthocyanidin‐free genotypes, by lowering total polyphenol content or polyphenol oxidase (PPO) activity through abrasion, by heat treatment, by exclusion of oxygen, and by the use of enzyme inhibitors.  相似文献   

19.
Abstract

Iron deficiency in humans is the most prevalent micronutrient deficiency worldwide. To screen for high Fe cultivar, genotypic variation in Fe concentration of barley grain was investigated in two collections of barley: 274 standard varieties selected at the Barley Germplasm Center of the Research Institute for Bioresources, Okayama University (SV) and 135 varieties from the Barley Core Collection of Americas (BCCAM). The Fe concentration of barley grain showed large variation, ranging from 24.6 to 63.3 mg kg?1 in SV, from 21.0 to 83.0 mg kg?1 in BCCAM barleys. The Fe concentration was not affected by the key characters of barley varieties, kernel row types, and hulled or hull-less. The Fe concentration was also not related to the place of origin of the barley variety. About 90% of total Fe was localized in the grain without hull. These results provide fundamental data for breeding Fe-rich cultivars and for studying the mechanisms involved in genotypic variation in Fe concentration.  相似文献   

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