四棱豆优良品种的引种和良种选育研究

1998～ 1999年 ,在四川南充市对 15份四棱豆材料进行了引种和良种选育试验。选出了适合四川南充地区栽培的 4个优良品种 ,其中 96 - 13具早熟、高产、抗病特性 ;K0 0 0 9和K0 0 10具高产、抗病特性 ;96 - 14 - 1具矮生直立、抗病特性。     

DPC对棉花叶片发育及活性氧代谢的影响

以中棉所１８为材料，研究了大田条件下ＤＰＣ（缩节安）系统化控对棉叶发育和活性氧代谢的影响，结果表明，ＤＰＣ提高了叶片中叶绿素、可溶性蛋白的含量，降低和减轻了膜脂过氧化产物丙二醛（ＭＤＡ）的积累，提高了超氧物歧化酶（ＳＯＤ）活性，降低了过氧化氢酶（ＣＡＴ）、过氧化物酶（ＰＯＤ）活性，改善了活性氧代谢。ＤＰＣ具有显著延缓叶片衰老的效应，可能与改变了内源激素系统、改善了活性氧代谢有关。     

陆地棉×亚洲棉F_0成胚频数与亲本主要产量性状配合力的关系

陆地棉×亚洲棉F_0成胚频数主要受母本陆地棉的影响,不同的7个陆地棉品种间存在着显著差异.成胚频数高的6901和朝阳1号,单铃子棉重、单铃种子数、子指一般配合力亦均高;而成胚频数低的6913和黑山棉,上述各性状的一般配合力也均低.在7个父本亚洲棉中,与陆地棉杂交当代成胚频数高的束鹿白花和完紫,其子指的一般配合力也较高.因此,选择单铃子棉重、单铃种子数、子指一般配合力较高的陆地棉作母本与子指一般配合力较高的亚洲棉作父本杂交,可以显著提高种间杂交当代的成胚频数.     

核不育芝麻小孢子败育机理的细胞学研究

核不育芝麻小孢子败育发生在四分体形成之后的无液泡小孢子期,败育在很短的时间内完成。败育前小孢子大量液泡化,其线粒体异常膨大与质体的基质化可作为小孢子开始败育的标志。败育小孢子缺少花粉外壁上的覆盖层。芝麻花药绒毡层的异常,包括有机物贮量的降低;细胞内含物的异位分布及迅速减少与消失;不能及时或缺乏分泌胼胝质     

珂字201胚性愈伤组织cDNA文库的构建和分析

用经过改进的胍盐法提取了陆地棉品种珂字201胚性愈伤组织的总RNA,进而分离了mR-NA,合成了全长cDNA,并将其克隆到λTriplEx载体中,进行体外包装后,成功地获得了cDNA文库.该文库的滴度为2.02×107pfu·ml-1,重组效率在90%以上,插入片段大小范围也符合cDNA文库构建的要求.     

Performance of Solanum habrochaites LA1777 introgression line hybrids for marketable tomato fruit yield in Asia

Wild relatives of the cultivated tomato (Solanum lycopersicum L.) are major sources of new genetic diversity for tomato improvement. Introgression lines (IL) are near-isogenic lines homozygous for one or several mapped wild DNA fragments in a common recurrent parent. A set of ILs developed by Cornell University from Solanum habrochaites accession LA1777 and recurrent parent E6203 has been made publicly available through the Tomato Genetics Resource Center of the University of California-Davis. Our objective was to identify LA1777 introgressions with potential to increase the marketable fruit yield of tomato grown in the tropics. A subset of ILs were each crossed to CLN2498E (resistant to bacterial wilt and some begomoviruses) to create IL hybrids (ILH). ILH, IL recurrent parent E6203, CLN2498E, and CLN2498E × E6203 (Hchk) were evaluated in replicated trials in Thailand, India, and Taiwan during two dry seasons. Highly significant effects for marketable fruit yield were detected in Thailand and Taiwan. ILH heterozygous for S. habrochaites segments at the bottom of chromosome 1 yielded about 20% than the Hchk at Thailand and Taiwan. Our results agree with previous results from Cornell University researchers who found a segment of S. habrochaites DNA located between TG158 and TG27 associated with increased total fruit yield in previous trials conducted in upper state New York. Yield improvement due to this S. habrochaites introgression can occur over a wide range of environments.     

Cannabinoids for the pharmaceutical industry

Summary Cannabis sativa, is a rich source of a variety of compounds, including cannabinoids, terpenoids and flavonoids. Their content depends upon the plant genetics, growth conditions, time of harvest and drying conditions. To date, more than 60 different cannabinoids have been identified in the plant. Cannabis has been used medicinally for 4000 years and remained in the British pharmacopaeia until 1932, and in the British Pharmaceutical Codex until 1949. Medical use has been prohibited in the UK since 1973. The principal cannabinoid, delta-9-tetrahydrocannabinol (THC) was first isolated in 1964; the first cannabinoid pharmaceutical product Marinol® (a synthetic THC product) was approved in the USA in 1985. The discovery of specific cannabinoid receptors in the early 1990s and subsequent identification of the endocannabinoids anandamide and 2-arachadonoylglycerol, led to a resurgence of interest in the field of cannabinoid medicine, especially within the pharmaceutical industry. Cannabidiol (CBD), as a non-psychoactive, cannabinoid is currently a cannabinoid of significant interest, showing a wide range of pharmacological activity. The other classes of compounds present in cannabis also have their own pharmacology (e.g. terpenoids, flavonoids). The potential for interaction and synergy between compounds within the plant, may play a role in the therapeutic potential of cannabis. This may explain why a cannabis-based medicine using extracts containing multiple cannabinoids, in defined ratios, and other non-cannabinoid fractions, may provide better therapeutic success and be better tolerated than the single synthetic cannabinoid medicines currently available. The development and employment of one of these medicines, Sativex®, is described.     

Photoperiod sensitivity gene controlling heading date in rice cultivars in the northernmost region of Japan

Rice is grown in diverse environments at latitudes ranging from 53^°N to 40^°S. In Japan, Hokkaido is the northernmost rice cultivation region(42–45^°N latitude). Only extremely early maturing (heading) varieties that have extremely low photoperiod sensitivity are adapted to this area. Heading date is the most important trait in adaptation to this particular environment. Also, the efficient manipulation of heading date is a crucial component of rice improvement. To determine the genetic basis for heading date among cultivars grown in Hokkaido, the heading behaviour was analyzed. Clear segregations were observed. To estimate the photoperiod sensitivity of the genes involved, the cultivars and F₁ plants from crosses between the cultivars were grown under different daylength conditions. The results indicated that the genes controlling heading date are photoperiod sensitive, suggesting they play important roles in the northernmost rice cultivation regions in Japan, to which only cultivars with extremely low photoperiod sensitivity are adapted. This revised version was published online in August 2006 with corrections to the Cover Date.     

Genetic variation for dry matter and nitrogen accumulation and translocation in two-rowed spring barley: I. Dry matter translocation

A 4-year field study was carried out to determine dry matter and nitrogen accumulation until anthesis and at grain filling period and dry matter translocation and utilization in grain filling of barley. Twenty two-rowed spring barley (Hordeum vulgare ssp. distichum L.) cultivars originated from different countries (Yugoslavia, Germany, Australia, the Czeck Republic, Netherlands, France and USA) were grown during 1995–1998 on a non-calcareous chernozem soil near Novi Sad (45° 20′N, 15° 51′E, 86 m asl). Dry matter and nitrogen accumulation depended on the cultivar and year. In a year with favorable weather conditions, 58% of dry matter was accumulated during pre-anthesis, while in a year with less favorable weather the amount was 48%. In the favorable year 91% and in unfavorable year 65% of nitrogen was accumulated until anthesis. The results indicated that the greater amount of dry matter and nitrogen accumulated before anthesis. Dry matter translocation efficiency depended on the cultivar and ranged from 3 to 16.4%, while the contribution of pre-anthesis assimilates to kernel varied from 4 to 24.2%. Cultivars that have been developed for the growing conditions of the area where the experimental site was located, i.e. adapted ones, did not use pre-anthesis dry matter for grain filling. High positive correlations (P<0.01) were found between biomass at anthesis and biological yield, dry matter translocation efficiency, contribution of translocated dry matter to grain yield, and total plant nitrogen at maturity. Accumulated nitrogen at anthesis was positively correlated (P<0.01) with growing degree–days until anthesis, dry matter at anthesis and dry matter translocation parameters. Heritability for the investigated characters was rather high, over 0.60.