常温条件下花生种质资源超干燥贮藏研究

不同含水量的花生种子在常温下，密封干燥贮藏7、9、11、12a，对其种子发芽率、发芽势、活力指数、植株生长发育以及植物学特性和经济性状有不同程度的影响。在武汉气候条件下，花生种子含水量处于3．2％～3．3％的超千状态下，至少可安全贮藏11年。     

Influence of the stage of ripeness on phenolic metabolism and antioxidant activity in table grapes exposed to different CO2 treatments

We have analyzed the influence of the stage of ripeness on L-phenylalanine ammonia-lyase (PAL) gene expression, accumulation of anthocyanins and total phenolics, and on antioxidant activity in the skin of table grapes treated with 20% CO₂ + 20% O₂ + 60 % N₂ for 3 or 6 d at low temperature (0 °C). The residual effect of high CO₂ treatment after transfer to air was also studied. In early harvested grapes, neither the anthocyanin content nor the accumulation of VcPAL mRNA was affected by any of the CO₂ treatments applied. However, in late harvested grapes, the duration of high CO₂ treatment determined its effect and a 6 d treatment with CO₂ sustained higher levels of total phenolics and anthocyanin accumulation, and VcPAL expression than observed in untreated late harvested grapes. The increased antioxidant capacity was correlated with the total amount of phenolics and anthocyanins. Conversely, in grapes treated for 3 d with CO₂ the phenylpropanoid pathway did not appear to be induced and a relationship between antioxidant activity and anthocyanins was not observed. Thus, further studies are needed to identify the most important antioxidants in these treated fruit.     

Development of Sequence-characterized DNA Markers Linked to Temperature Insensitivity for Fruit Production in Longan (Dimocarpus longan Lour.) Cultivars

In this paper, we characterize a temperature dependence in longan (Dimocarpus longan Lour.) cultivars using the high annealing temperature random‐amplified polymorphic DNA (HAT‐RAPD) methodology. This form of genomic analysis allows a random sampling of the complete genome to provide information about phenotypic traits of interest. Using a set of 18 unique decamer primers, polymorphic bands ranging from 100 to 2500 bp were examined for 14 longan varieties from which banding patterns of interest were selected for conversion to the more reproducible and robust sequence characterized amplified region (SCAR) markers. In particular, one SCAR marker produced an electrophoresis banding pattern which could distinguish between longan varieties requiring a sustained interval at low temperatures for fruit production vs. those that do not. This band was composed of a nucleotide region 275 bases in length (DQ539047) in which the initial 90 nucleotides were >85 % identical to the 12‐oxophytodienoic acid (OPDA) reductase gene. OPDA is an immediate precursor to jasmonic acid which has been described as the ‘master switch’ for lipid‐derived environmental signalling to factors such as flowering and osmotic stress. The possible involvement of the jamonic acid signalling pathway could explain the recent success of potassium chlorate to induce off‐season flowering and fruit formation.     

湘南红壤区牧草生产的气候模型

利用湖南省祁阳县的长期气象数据，结合不同牧草的生长特性，建立了一个反映当地牧草生长状况的气候模拟模型，并据此气候模型评价了当地气候条件对牧草生产的影响，鉴定了牧草周年生长的限制性因子。根据气候模型预测出温带牧草的最佳播种时期在１０月中旬至１１月下旬，热带牧草最好在３月下旬至４月中旬播种。牧草生长气候模型还可用于指导牧草品种筛选及牧草生产管理。     

机械密封实验台流体温度控制系统

为了方便地控制机械密封实验台流体的温度,运用单片机作为主控机,设计了一套流体温度控制系统。主要介绍了机械密封流体温度控制的基本原理,并建立了机械密封流体温度控制的数学模型。系统软件的设计采用C语言,通过C51编译器将C程序转化为汇编语言程序。对该控制系统进行了仿真。设计结果表明,该方案是可行的并适用于其他温度控制系统,为机械密封实验台的设计提供了参考。     

DS1820数字温度计在微机温度采集系统中的程序编制

采用DS1820数字温度计实现的微机温度采集系统，硬件结构简单．为了保证正确地采集温度数据，必须严格按照DS1820与主机的通信协议编制程序．     

短高温对小麦花器官及旗叶的超微结构变化的直接影响

在春小麦花粉母细胞期和单核期进行短期高温杀雄处理后，用透射电子显微镜观察小麦花器官和旗叶的超微结构。结果表明：短期高温直接使小孢子和绒毡层细胞中线粒体等双层细胞器严重破坏，并且使绒毛层细胞膨胀与小孢子粘连。而胚囊的线粒体和旗叶片中的 纯粒体及叶绿体结构变化不明显。     

Effect of temperature on bulb growth capacity and sensitivity to summer sprouting in Lilium longiflorum Thunb.

The production of Lilium longiflorum bulbs in The Netherlands, with its cool climate, has been a problem because of unsatisfactory bulb growth and the risk of premature sprouting of the daughter bulbs (summer sprouting). To investigate the possibilities of breeding a type of L. longiflorum that can be grown under cool climatic conditions, a collection of 27 L. longiflorum cultivars from Japan, The Netherlands and the United States was tested, together with two Asiatic hybrids and a L. speciosum cultivar, under low phytotron temperatures (10, 14, 17°C) and in field experiments.‘Mount Everest’, ‘Saeki’, ‘Indian Summer’ and ‘White American’ were among the best L. longiflorum cultivars, with less than 20% summer sprouting and good bulb production. This was in contrast to ‘Hinomoto’, ‘Ace’ and some American introductions, which showed more than 60% summer sprouting and low bulb production. The lower the phytotron temperature, the more summer sprouting occurred. The differences observed between the cultivars in the field experiments were in agreement with those observed in the phytotron. The genetic variation proved large enough to start a breeding program for L. longiflorum adapted to cool climate conditions.     

鸡肠道抗菌肽的提取及活性研究

取新鲜鸡肠黏膜超声波破碎,乙酸浸提,经Sephadex G-50层析后,收集具有抑菌活性的组分进行超滤离心,抑菌实验表明滤过物具有抑菌活性.滤过物经SDS-PAGE分析为一个条带,分子量约为6.078KD,得到电泳纯的鸡肠道抗微生物肽.该肽具有一定的耐热性,但经90℃以上热处理后活性下降较大;pH值对其活性影响较大,在pH6～8时活性最强.     

常温仓低温仓储存小麦品质变化规律研究

通过对储存在常温仓、低温仓内的小麦品质指标测定,找出与储藏时问相关的敏感指标变化规律,提出了常温和低温储藏条件下小麦合理的储藏期和轮换周期.