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111.
112.
Masuda K Sakaguchi M Saito S Deboer DJ Yamashita K Hasegawa A Ohno K Tsujimoto H 《Veterinary dermatology》2002,13(1):55-61
Three dogs were examined because of episodes of recurrent pruritic dermatitis in the spring, the season of Japanese cedar (Cryptomeria japonica, CJ) pollination in Japan. The dogs were shown to be sensitive to CJ pollen allergen using intradermal testing and antigen-specific IgE measurement. Fluorometric enzyme-linked immunosorbant assay (ELISA) showed increased concentrations of IgE specific to Cry j 1 and a negative result for Cry j 2 in the three dogs. The concentrations of IgE specific to Cry j 1 during the season of CJ pollination were higher than the concentrations found during the off-season in all the dogs, and the variation in the concentrations correlated with the variation in clinical signs. Peripheral blood mononuclear cells showed apparent proliferative responses to crude CJ pollen antigen and Cry j 1 during CJ pollination season. These findings indicated that Cry j 1 was the major allergen recognized by IgE and lymphocytes and resulted in the development of type I hypersensitivity to CJ pollen allergen in these atopic dogs. 相似文献
113.
Due to the protogynous dichogamy of cherimoya and to the absence of proper pollinating vectors, hand-pollination with fresh pollen is a common practice for cherimoya commercial production. In order to optimize the process of hand-pollination, in this work we have studied the conservation of cherimoya pollen at −20, −80 and −196 °C for up to 3 months. In vitro pollen germination of fresh pollen was 57.1% and it was progressively reduced with conservation time at the three temperatures studied reaching a minimum after 3 months of storage of 10.4%, 14.2% and 13.6% at −20, −80 and −196 °C, respectively. Differences in germination among temperatures were only significant during the first 2 weeks of storage. Field pollinations with pollen stored for up to 3 months at the three temperatures show no yield differences compared to pollinations performed with fresh pollen. The results indicate that pollen collected and stored at sub-zero temperatures at the beginning of the cherimoya blooming season can be used along the whole blooming season avoiding the need of collecting fresh pollen daily. 相似文献
114.
西瓜成熟花粉的超微结构 总被引:1,自引:0,他引:1
为了解西瓜成熟花粉的超微结构特点,特别是营养细胞和生殖细胞之间的关系,选取刚开花的西瓜雄花采集花粉,2.5%戊二醛固定并制成超薄切片,透射电镜观察照相。结果表明,西瓜成熟花粉粒中营养细胞含丰富脂类储藏物质和内质网,内质网堆叠,周围和间隙中充满脂类物质;含丰富高尔基体和大量小泡;质体很少。营养核通常深度开裂,产生多数裂片,裂片伸向生殖细胞。生殖细胞流线型,细胞壁电子透明,细胞核伸长,细胞质含高尔基体、内质网,不含质体。生殖细胞表面产生波状突起,波峰背离营养核。生殖细胞一端伸入营养核裂片间隙,2者构成雄性生殖单位。 相似文献
115.
热激处理对桃,李离体花枝2n花粉产生的影响 总被引:14,自引:1,他引:13
对桃和李通过休眠的花枝在20℃条件下进行水培,减数分裂前期Ⅰ进行32℃、12h热激处理,小孢子母细胞减数分裂四分体时期二分体发生频率为5.82%~16.06%,2n花粉比例为13.33%~20.37%,处理后花粉离体萌发率较低;30℃恒温培养导致花蕾败育。二分体频率重复间、花朵间和品种间差异显著。 相似文献
116.
Sorghum [(Sorghum bicolor L.) Moench] is a highly productive crop plant, which can be used for alternative energy resource, human food, livestock feed or industrial purposes. The biomass of sorghum can be utilized as solid fuel via thermochemical routes or as a carbohydrate substrate via fermentation processes. The plant has a great adaptation potential to drought, high salinity and high temperature, which are important characteristics of genotypes growing in extreme environments. However, the climate change in the 21st century may bring about new challenges in the cultivated areas. In this review, we summarize the most recent literature about the responses of sorghum to the most important abiotic stresses: nutrient deficiency, aluminium stress, drought, high salinity, waterlogging or temperature stress the plants have to cope with during cultivation. The advanced molecular and system biological tools provide new opportunities for breeders to select stress‐tolerant and high‐yielding cultivars. 相似文献
117.
118.
H. F. W. Rattunde 《Plant Breeding》1998,117(1):33-36
Landrace cultivars represent potentially valuable source material for breeding dual-purpose (grain and stover) sorghums. To characterize the genetic variation and interrelationships for major agronomic traits among potential dual-purpose sorghum landraces, 74 accessions, primarily from Southern Africa, the Sudan, and India, were evaluated in five environments at Patancheru, India. These environments, at 17°N with 520-540 mm rainfall during the growing season, are representative of the major sorghum-growing areas in India and the Sudanian Zone of Western and Central Africa. Significant genetic variation and high heritabilities (P = 0.01, h2= 0.63-0.92) were observed for seedling vigour, grain and stover yields, growth rate and harvest index. Time to flower was correlated with stover yield (r = 0.48, P = 0.01) and an index (Iev) of total economic value (r = 0.44, P = 0.01) but not with grain yield (r = 0.22, P = 0.05). Grain and stover yields varied independently (r = 0.22, P = 0.05) and were similarly related to Iev, values (r = 0.79 and r = 0.77 (P = 0.01), respectively). The 13 landraces with the highest Iev values (adjusted for maturity) had above-average growth rates and harvest indices that ranged from 20 to 38%. Landraces from Botswana and India were more highly represented in the high Iev set than in the full set of accessions. 相似文献
119.
120.
Mo Fatemi 《Biological conservation》2009,142(7):1461-1468
Wind-facilitated migration of new genotypes into small, geographically disjunct populations should buffer them against local extinction. Bertya ingramii, a monoecious, wind-pollinated shrub, is restricted to three populations in a 4 km2 area in eastern Australia. Populations are separated by deeply dissected gorges where it is unlikely that seeds are exchanged but where wind movement may facilitate pollen dispersal. Using 156 highly polymorphic ISSR markers, we found moderate genetic variation within and among populations of B. ingramii and less genetic diversity in a nearby and small population of the widespread Bertya rosmarinifolia. The smallest population of B. ingramii (<30 plants) had the highest genetic variation (65% polymorphic markers, Shannon Information Index = 0.30). AMOVA and a Bayesian analysis showed that molecular variance was equally distributed within and among populations suggesting that gene flow is as limited within as in among populations. Genetic distances between populations were only weakly explained by their relative geographic distances (mantel test, R2 = 0.21, P = 0.001) but the distribution of private bands, the departure from Hardy-Weinberg equilibrium, and a UPGMA tree showed that the smallest population of B. ingramii was generally more similar to an upstream population of B. rosmarinifolia. Thirty-eight percent of bands in this small population of B. ingramii were exclusively shared with B. rosmarinifolia. This covert hybridisation may have been an ancient event but may be responsible for contemporary declines in germination and establishment in B. ingramii. The conservation implications are amplified by the endangered status of B. ingramii. 相似文献