Content of Nutrient and Antinutrient in Edible Flowers of Wild Plants in Mexico

Nutrient and antinutritional/toxic factors present in some edible flowers consumed in Mexico were determined. The edible flowers were: Agave salmiana, Aloe vera, Arbutus xalapensis, Cucurbita pepo (cultivated), Erythrina americana, Erythrina caribaea, Euphorbia radians benth and Yucca filifera. The nutrient content in the flowers studied is similar to that of the edible leaves and flowers studied mainly in Africa. The moisture content of the flowers varied from 860 to 932 g kg⁻¹. Crude protein (CP) was between 113 to 275 g kg⁻¹ DM, crude fiber, 104 to 177 g kg⁻¹ DM and the nitrogen free extract, between 425 to 667 g kg⁻¹ DM. The highest chemical score (CS) was found in E. americana and A. salmiana; in five samples the limiting amino acid was lysine, and in three of them it was tryptophan. Trypsin inhibitors and hemaglutinnins had a very low concentration. Alkaloids were present in both the Erythrina species and the saponins in A. salmiana and Y. filifera. Cyanogenic glucosides were not found in the studied flowers. The traditional process of preparing these specific flowers before consumption is by cooking them and discarding the broth; in this way the toxic substances are diminished or eliminated. These edible flowers from wild plants consumed in local areas of the country play an important role in the diet of the people at least during the short time of the season where they are blooming.     

荔枝蛀蒂虫光驱避防控技术田间应用效果评价

【目的】研究荔枝蛀蒂虫光驱避防控技术在不同荔枝品种上的田间应用效果,以及对荔枝产量、品质和果园其他昆虫的影响,为荔枝蛀蒂虫绿色防控提供技术支持。【方法】2019—2020年,分别在广西钦州市钦北区、灵山县、浦北县和桂平市对三月红、妃子笑、桂味、鸡嘴、无核等早中晚熟荔枝品种开展荔枝蛀蒂虫光驱避防控技术田间试验,设光驱避（...     

拟鲌和梭鲈血清蛋白的电泳研究

作者应用琼胶电泳法对拟鲌和梭鲈的血清旦白成分进行了研究。研究证明．这两种鱼的血清旦白可分离出6—7个主要区带。几种旦白成分在鱼类不同性周期的各个时期是不恒定的，在产卵时期变化明显。拟鲌和梭鲈血清中几种旦白成分含量的季节变化具有共同规律。     

海南农民稻田生物多样性保护认知评价 及农药使用情况分析

长期以来农药的不合理利用已经引发了环境污染、食品安全等一系列问题、探索减少农药投入的生产 模式、构建稻田生物多样性生态控制病虫害的水稻生产模式已经成为稻田可持续发展的重要手段之一。 为了更好 地开展海南稻田生物多样性保护、发挥稻田生态系统服务功能、有必要系统全面地了解农民对稻田生物多样性保护 认知及农药使用情况、我们在海南北部和南部分别开展了调查。 结果显示、调查区大部分稻农对稻田生物多样性概 念不了解、相关知识掌握较少、且仅有极少数农民接受过相关的多样性种植培训或者指导。 在农药使用上、存在过 量使用、盲目使用和跟风使用等一系列不科学问题、直接导致海南稻田生态系统遭到破坏、种植成本骤增、稻农净收 益降低。 通过分析、就海南水稻生产中的农药使用问题提出了意见和建议。     

Identification and characterization of lactic acid bacteria isolated from rainbow trout, Oncorhynchus mykiss (Walbaum), with inhibitory activity against Lactococcus garvieae

A study was conducted to evaluate the probiotic properties of endogenous rainbow trout microbiota against pathogenic Lactococcus garvieae. A total of 335 bacterial strains were isolated from rainbow trout and screened for antagonistic activity against L. garvieae using an agar spot assay. Antagonistic strains were grouped by PCR amplification of repetitive bacterial DNA elements (rep‐PCR) and identified by 16S rRNA gene sequence analysis. The results revealed that the antagonistic strains belonged to the genera Lactobacillus, Lactococcus and Leuconostoc. Further probiotic characteristics, such as specific growth rate, doubling time, resistance to biological barriers, antibiotic resistance, hydrophobicity and production of antimicrobial substances, were also studied. These strains were able to survive low pH and high bile concentrations, showed good adherence characteristics and a broad spectrum of antibiotic resistance. The antagonistic efficacy was maintained after sterile filtration and was sensitive to proteinase K, indicating that proteinaceous extracellular inhibitory compounds were at least partially responsible for pathogen antagonism. Based on these results, these strains should be further studied to explore their probiotic effects in challenge experiments in vivo. This study shows clear evidence that the indigenous trout‐associated microbiota may provide a defensive barrier against L. garvieae.     

Effect of carazolol on the oestrous behaviour and concentrations of luteinising hormone and steroids in lactating cows during the periovulatory period

Twelve multiparous, cycling, lactating Holstein-Friesian cows were synchronised with prostaglandin F(2alpha) and treated with either 2.5 mg carazolol or saline. There were no differences between the peripheral blood concentrations of oestradiol or progesterone, but in the cows treated with carazolol the periovulatory surge of luteinising hormone was delayed, and oestrous behaviour was expressed later than in the control cows.     

Cloning and Sequence Analysis of Lipoxygenase Gene cDNA from Cucumber Fruit （Cucumis sativus L.）

Lipoxygenases are nonheme-iron-containing dioxygenases that catalyze the hydroperoxidation of unsatrated fatty acids containing a cis, cis-1,4-pentadiene structure producing hydroperoxy acids with conjugated dienes. LOX activity has been found in a wide range of plants. Typical substrates for LOX in plants are linoleic acid and linilenic acid fatty acids. The function of various LOXs in plants is unknown, but their participation in all stages of plant growth and development has been suggested （Hildebrand, 1989; Siedow, 1991）. Some of the physiological processes in whicn lipoxygenses have been implicated include wounding （Saravitz and Siedow, 1996）, pathogen attack （Melan et al., 1993）, seed germination （Kato et al., 1992）, fruit ripening （Ferrie et al., 1994）, plant senescence （Paliyath and Droillard, 1992）. The study on the role of lipoxygenase in ripening and senescence fruit focused on tomato and strawberry. Cloning LOX gene of cucumber fruit will make us further understand the molecularaction mode of this enzyme during fxuit ripening and senescence. In this paper we isolated the partial nucleotide sequences of cucumber fiuit lipoxygenase gene and discuss the characterization of it.     

软质小麦品质性状与酥性饼干品质参数的关系研究

选用我国17份软质小麦品种（系）在3点种植2年，研究软质小麦品质性状与酥性饼干品质的关系，探讨优质饼干品种的筛选指标。结果表明，粉质仪和拉伸仪参数与饼干品质的相关系数较小；吹泡仪弹性、吹泡仪弹性/延伸性、碱水保持力（AWRC）、碳酸钠溶剂保持力（SRC）和蔗糖SRC与饼干直径关系密切，相关系数分别为－0.79、－0.75     

The Application of TDZ in Enhancing Regeneration of Transgenic Plants

At present, transgenic plants are globally grown. Availability of a reliable regeneration system predominantly from a single transformed cell is the prerequisites for gene transfer, but regeneration is still a key problem （Wenzel, 2006）. The application of genetic modification technology in plants is closely related to the efficiency of the regeneration protocol. Shoot formation is oilen enhanced by the combination of auxins and cytokinins. TDZ （Thidiazuron, N-phenyl-N＇-1,2,3-thiodiazol-5-ylurea）, a non-purine, has been shown to promote differentiation of organized centers of growth in cultured tissues at much lower concentrations, and shoot regeneration occurs with an efficiency comparable to or greater than that of other cytokinins （Fiola et al., 1990）. By addition of TDZ, a series of plants which were difficult to culture in vitro or less sensitive to plants growth regulators obtained somatic embryos and regenerated plants, some of them have become the eminent transformation system for genetic engineering. TDZ has been reported to be very efficient in stimulating adventitious shoot production in several recalcitrant plants. TDZ is considered as a potential growth regulator for in vitro shoot regeneration and somatic embryogenesis of several crops. This review summarized how the new growth regulator TDZ to affect the regeneration of transgenic plants.