Growth and fatty acid composition of sesame (<Emphasis Type="Italic">Sesamum indicum</Emphasis> L.) genotypes as influence by planting dates and nitrogen fertilization in semiarid region of Northwest,Pakistan

A field experiment was conducted on silty clay loam soil in the years 2011–2012. Two sesame (Sesamum indicum L.) cultivars (Local Black and Local White) were evaluated using various 3 different sowing dates (20th June, 10th and 30th July) and four agrotechnical level (0, 40, 80 and 120 kg N ha^–1) at New Developmental Farm The University of Agriculture, Peshawar, Pakistan. The objective of this study was to evaluate the effects of sowing dates on growth, yield and oil fatty acid composition of two sesame cultivars grown under different nitrogen fertilization. Results showed that cv. Local Black was characterized by significantly higher content of oil (47%), seed yield (696 kg ha^–1) and oil yield (335 kg ha^–1) while cv. Local White had higher palmitic acid (8%) and linoleic acid (38.7%). Yield and its main components were positively affected by the earlier sowing date. With regard to fatty acid composition, a decrease in oleic and stearic acid and an increase in linoleic and palmitic acid were observed. At early sowing, oleic and palmitic acid decreased whereas linoleic and stearic acid increased. The decrease in the oleic/linoleic acid ratio observed at early sowing, suggests a possible role of temperature on the activity of oleate desaturase in the developing seeds. Intensive technology of cultivation (120 kg N ha^–1), compared to the economical technology (40 kg N ha^–1), significantly increased the seed yield of both sesame cultivars. This was due to higher number of branches, Capsules m^–2, capsules plant^–1, seeds capsule^–1 and 1000 seed weight (g). The intensive technology of cultivation had a beneficial effect on the content of palmitic acid, linolenic acid and oleic acid in sesame seed.     

TDZ对仙客来不同外植体再生的影响

在无菌条件下培养仙客来种子,并以无菌萌发植株的子叶节、子叶、叶片及叶柄为外植体进行芽分化诱导。试验结果表明,不同浓度TDZ对各外植体的诱导效果不同,用子叶节、子叶、叶片及叶柄均可诱导出再生芽,但以叶片为材料的诱导效果最佳,其中1.0 m g/L TDZ对叶片再生芽的诱导效果最好,而子叶以0.5 m g/LTDZ、子叶节和叶柄以0.2 m g/L TDZ诱导再生芽的效果较好。     

水分胁迫对番茄叶片气孔传导及光合色素的影响

以栽培番茄品种AilsaCraig的6叶期幼苗为试验材料,在水培条件下研究了50,75和100g/LPEG水分胁迫对叶片气孔传导、光合色素含量及发叶速度的影响。结果表明,水分胁迫使气孔传导度和发叶速度降低,光合色素增加。气孔传导度和发叶速度的降低均与水分胁迫强度和持续时间有关,而光合色素的增加主要与胁迫持续时间有关。     

Impact of genetic and environmental variation on development of flavonoids and carotenoids in pepper (Capsicum spp.)

Peppers (Capsicum spp.) were grown for phytochemical analyses at three different locations including a greenhouse at College Station and field plots at Uvalde and Weslaco, Texas. Cultivar effects were significant at each location for all compounds. The best sources of β-carotene were mature greenhouse-grown fruit of Fidel (23.7 μg/g) and C 127 (22.3 μg/g). Mature greenhouse fruit of Tropic Bell (10.1 μg/g) and PI 357509 (9.2 μg/g) had high lutein, but Uvalde field-grown mature fruit of these lines were low in this compound, (1.4 and 0.5 μg/g, respectively). MJ 201 fruit had the highest zeaxanthin levels (10 μg/g) at both College Station and Uvalde. The best sources of quercetin over all locations were the yellow wax types, Banana Supreme (186 μg/g), PI 357509 (86 μg/g) and Rio Grande Gold (26 μg/g). Fidel (37 μg/g) and Banana Supreme (21.5 μg/g) were the best sources of luteolin. Immature fruit generally contained lower levels of lutein and xeaxanthin than mature, colored fruit. These differences were not always statistically significant. Greenhouse-grown peppers at College Station contained more carotenoids than the field-grown peppers in Uvalde and Weslaco, but there were no significant differences among locations for flavonoid concentrations. Several good candidate parents were identified for the breeding program to develop novel pepper varieties with increased health benefits. Families of these varieties are currently being examined to assess the impact of specific environmental factors and identify genes involved in regulating synthesis of these beneficial phytochemicals.     

外源亚精胺对干旱胁迫下番茄幼苗碳水化合物代谢及相关酶活性的影响

以耐旱性不同的2个品种番茄(‘毛粉802’和‘皇冠’)为试材,采用营养液栽培,研究了7.5%聚乙二醇(PEG)模拟的干旱胁迫下喷施外源亚精胺(Spd)对番茄幼苗植株碳水化合物代谢及相关酶活性的影响。结果表明,外源Spd处理不同程度地提高了干旱胁迫下番茄幼苗叶片中蔗糖、葡萄糖和果糖的含量,增加了叶片中蔗糖合成酶(SS)、磷酸蔗糖合成酶(SPS)活性,降低了叶片中淀粉含量。Spd通过促进幼苗叶片内糖类的转换和利用,进而影响碳水化合物含量,参与了干旱胁迫下番茄幼苗碳水化合物的代谢过程,促进了幼苗形成新的代谢平衡,表明幼苗体内碳水化合物代谢与多胺之间关系密切。     

Application of abscisic acid (ABA) at veraison advanced red color development and maintained postharvest quality of ‘Crimson Seedless’ grapes

‘Crimson Seedless’ is a popular table grape cultivar, but in warm-climates, its fruits often fail to develop adequate red color, even after they have been treated with ethephon. Application of abscisic acid (ABA) may improve color more effectively than ethephon, but its potential effects on postharvest quality must be considered before recommending its use on table grapes. Therefore, we compared the postharvest quality attributes of grapes treated preharvest with 250 μL L⁻¹ ethephon, the current industry standard, to that of grapes treated with 150 or 300 μL L⁻¹ ABA, or nontreated. Treatment with either ethephon or 150 μL L⁻¹ ABA allowed grapes to be harvested 10 d before nontreated fruit, and fruits treated with 300 μL L⁻¹ ABA attained marketable quality 30 d before nontreated fruit. Early harvest was possible because the treatments induced more rapid coloring of the grapes, and though total yield was not affected by any plant growth regulator (PGR), all PGRs doubled packable yields by improving the color of the grapes. ABA-treated grapes were characterized by superior appearance both in berries and clusters’ rachises compared to ethephon-treated and control grapes. Other quality attributes such as firmness, berry weight, decay incidence, and shatter remained unaffected among treatments. Therefore, ABA is an effective alternative to ethephon for enhancing the color and maintaining postharvest quality of ‘Crimson Seedless’ grapes.     

Ripeness estimation of grape berries and seeds by image analysis

Digital imaging has become a powerful tool for the characterization and quality control of foodstuff. Because of the need to automate processes, faster tools are needed and Computer Vision is a good alternative to chemical analysis of many products in quality control. Appearance of grape seeds and grape berries change during the ripeness. These changes are closely related to the chemical composition, especially phenolics, which are very important compounds due to their implications on the intensity and stability of red wine colour. In this study, a complete characterization of grape seeds and grape berries by digital image analysis is described. The size of grapes and the veraison has been determined by image analysis and it has been also established an objective Browning Index of seeds. Morphological differences between varieties were studied by applying discriminant analysis models which allowed us to classify the grape seeds with high accuracy.     

转葡聚糖酶和防御素基因的番茄植株及其对番茄灰霉病的抗性

用根癌农杆菌Agrobacterium tumesfaciens介导法，将烟草β-1，3-葡聚糖酶Glucanase基因、苜蓿防御素alfAFP基因及二者双价基因导入番茄Micro—Tom中，以期获得抗灰霉病的转基因株系，并比较验证双价基因是否具有协同作用。绿色荧光蛋白基因（GFP）活性检测、PCR和Southem杂交检测表明，外源基因分别以1—4个拷贝整合到番茄基因组中。对T1代植株进行接种鉴定表明，转基因植株对灰霉病侵染的抵抗能力较对照明显增强，各株系的抗病能力与外源基因的表达相关，且葡聚糖酶基因和防御素基因对抗灰霉菌表现一定的协同作用。T1株系田间抗病鉴定结果表明，转基因株发病程度不同，病情指数在19—28之间，抗病性均高于对照。所得到的稳定表达的株系可作为抗病育种材料进一步研究。     

硫酸和PEG处理对多叶羽扇豆种子萌发和某些生理生化指标的影响

以多叶羽扇豆种子为试材,对其适宜萌发的条件进行了筛选,并对浓硫酸破除硬壳以及不同浓度的PEG处理后的某些生理生化指标进行了研究。结果表明,种子用浓硫酸处理后,再经20%PEG浸润在砂床。18~25℃变温和白天8 h光照的条件下培养效果最好。在种子萌发过程中,其外渗电导率和丙二醛(MDA)含量明显低于对照,发芽势、发芽率、活力指数以及过氧化物酶(POD)的活性显著高于对照,种子的贮藏蛋白、淀粉和可溶性糖的分解利用也明显快于对照,从而提高了种子的萌发和出苗率。     

FraxForFuture—research on European ash dieback in Germany

Journal of Plant Diseases and Protection - European ash dieback caused by the alien, invasive ascomycete species Hymenoscyphus fraxineus currently represents, along with its side effects, the...