菱花粉生活力测定方法研究

为了探索菱花粉生活力的最佳测定方法，以孝感红菱花粉为试材，利用无机盐培养法、MTF（四甲基噻唑蓝）染色法和TTC（氯化三苯基四氮唑）染色法对花粉生活力进行测定。研究结果表明．培养基中添加低浓度的蔗糖和硼酸对菱花粉的萌发有促进作用，菱花粉萌发的最适培养基为10％蔗糖＋0．005％硼酸，萌发率达65．9％：用MTT染色法和TTC染色法测定菱花粉生活力，染色率仅为36．9％和27．1％，效果不理想。     

The porcine sperm reservoir in relation to the function of hyaluronan

The oviduct plays a role in successful animal reproduction not only in spermatozoa and ova transport to the fertilization site but also by affording a microenvironment for fertilization and early embryonic development. The sperm reservoir (SR) is restricted in the uterotubal junction (UTJ) and caudal isthmus. Billions of porcine spermatozoa are distributed to the female reproductive tract during/after insemination, and small amounts of them are stored for about 36–40 hours in the SR, which maintains sperm viability in the pre-ovulation period through its surface epithelium and production of fluid. The SR regulates the release of spermatozoa so that only a small population moves towards the fertilization site (ampulla) to decrease polyspermy. This review attempts to provide information about the structure and function of the porcine SR, its intraluminal content (hyaluronan, HA), and the influences of HA on porcine spermatozoa in vivo. In pigs, the spermatozoa are stored in a mucous-like fluid within the UTJ and caudal isthmus in the pre-ovulation period. The oviduct fluid contains sulfated glycosaminoglycans (GAGs) and non-sulfated GAGs, i.e., HA. It is interesting to note that HA is synthesized by hyaluronan synthase-3 (HAS-3), and its receptor, CD44, is found in the epithelium of the porcine SR site. Additionally, sperm capacitation does not occur in vivo in the SR during the pre- and peri-ovulation periods, but spermatozoa in the SR will attempt to capacitate if exposed to bicarbonate. However, capacitation in the SR will rise in the post-ovulation period, indicating the role of HA in modulating sperm capacitation after ovulation. All data support the understanding that the porcine SR ensures the viability of fertile spermatozoa and maintains the non-capacitated status during the pre-ovulation period. This basic knowledge about the SR is believed to be useful to advance sperm preparation procedures for in vitro fertilization (IVF) and improve the preservation process of porcine semen.     

Engineered in situ bioremediation of soil and groundwater polluted with weathered hydrocarbons

In this work, we present our experience in the engineered in situ biostimulation of a hydrocarbon-polluted subsoil of an old metal-working plant. The site had a long history of fuel, lubricant oil, and diesel spills and leakages that were initially treated by means of physico-chemical techniques. After one year of treatment, weathered hydrocarbons were firmly sorbed in the unsaturated zone, limiting the effectiveness of the physico-chemical methods being applied. Also, low nutrient and dissolved oxygen levels limited natural attenuation yields. Therefore, a bioremediation approach based on the injection of hydrogen peroxide, an oleophilic fertilizer, and a surfactant was applied. Total petroleum hydrocarbons and gas chromatography-mass spectrometry determinations were performed as a chemical means of monitoring the process. Microbial populations, including the presence of hydrocarbon-degrading bacteria, were simultaneously analyzed during the process, using enrichment techniques and confocal laser scanning microscopy observations with fluorescent indicators. Hydrocarbon-degrading bacteria were already present in the polluted subsoil prior to the implementation of this bioremediation technique and increased noticeably during the first 2 months of treatment. Hence, the suitability of the nutrient and oxygen amending approach was confirmed as further demonstrated by chemical determinations.     

群体生存力分析在大额牛保种中的应用研究

由于外来种的大量引进和杂交利用,我国地方畜禽品种资源受到严重威胁,一些品种已濒临灭绝。本文以大额牛为例,在国内外首次用群体生存力方法模拟分析该珍稀牛种资源的生存过程和系统压力及遗传等影响因素。结果表明,大额牛目前的状况很危险,按现在的生存状况,群体平均灭绝时间为52～78年。除非采取轮回交配制度、降低死亡率、减少灾害发生频率、合理的公母畜交配比例等措施。在畜禽遗传资源保护行动中,不仅需从遗传本身考虑,正确解决系统压力问题更重要。     

高羊茅种子生活力丧失过程中遗传物质的降解

本文以高羊茅（Ｃａｍａｒｉｌｌｏ品种）种子为材料，采用人工加速老化的方法，对其老化过程中的ＲＮＡ和Ｐｏｌｙ＾ＲＮＡ进行研究，结果表明，随着才化种子发芽率的下降，干种子胚中的ＲＮＡ，ＰｏｌｙＲＮＡ含量均随之下降。在严重老化的种子中，则丧失其在发芽过程中新ＲＮＡ，ＰｏｌｙＡＲＮＡ的合成能力，同时大分子量的ＲＮＡ降解为小分子量的ＲＮＡ，并丧失其完整性，研究结果表明，在高羊茅种子人工加速老化的过程中，Ｐｏ     

辣椒花粉生活力最佳测定方法的筛选

研究结果表明：I－KI染色法，醋酸洋红染色法，TTC染色法，过氧化物酶沉淀法和培养基离体萌发法等5种方法的适用测定现采花粉的生活力，而要测定贮藏花粉的生活力只能用TTC染色法和培养基离体萌发法。不论对何种来源的辣椒花粉进行生活力测定，以离体萌发法所得结果最为直观，稳定，是测定辣椒花粉生活力的最佳方法。     

红麻种子超干贮藏研究

选用粤丰1号和青皮3号红麻种子为试材，进行超干贮藏研究。两品种种子的原始水分分别为13.69%和10.72%，经日晒降水至8.37%和9.10%，再用硅胶作干燥剂，将粤丰1号种子水分降至5.80%、4.65%、3.51%，青皮3号种子水分降至6.45%、5.22%、4.51%、3.70%。各水分种子分别密封贮藏于室温和0～5℃低温下，11个月后取出种子经室内水分平衡后测定生活力和活力。结果表明：超干贮藏和低温下适当低水分贮藏，均可使红麻种子保持较高生活力和活力。粤丰1号最佳水分，室温下的4.65%，低温下的8.37%；青皮3号最佳水分，室温下为4.51%，低温下为9.10%。     

基因库大豆种子繁殖更新阈值研究

试验研究了大豆种子恒温 (30℃ )抽真空密封贮存不同时间后与其活力相应的生理生化和农艺性状指标的变化。结果表明 :随种子贮存时间的延长 ,发芽率 (GP)、芽鲜重 (BFW )、出苗率(SEP)、株高、单株粒重、外渗量和脱氢酶活性降低 ,出苗天数和开花天数推迟 ,过氧化物酶谱带减少 ,其测定指标基本上都存在“三降点”(起始下降点、显著下降点和临界下降点 )。综合分析显示 :80 %发芽率可考虑作为大豆种子繁殖更新生活力标准 ,73%～ 86%之间所在的发芽率范围可考虑作为大豆种子繁殖更新阈值 ,73%可考虑作为基因库大豆种子繁殖更新的发芽率下限     

氧气浓度对杧果种子贮藏寿命的影响

杧果种子在所试各氧浓度中密闭贮藏时，含水量变化不大，但在21．0％和17．5％O2中贮藏20天后，颜色由白完全变黑，生活力完全丧失；在10．5％。。中贮藏100天，颜色保持白色，生活力达40％；在7．0％和3．5％O2中贮藏100天，种子颜色虽保持白色，但生活力已降至20％以下。推论除脱水损伤外，种子氧化变黑也是杧果种子表现顽拗性的一个主要原因。     

Provenance Variation in Seed Morphometric Traits, Germination, and Seedling Growth of Cordia africana Lam

Patterns of genetic variation in Cordia africana, a tropical timber species, were evaluated at the population level. Bulk seed samples were collected from six natural populations in Ethiopia and examined for variations in seed morphometric traits, seed germination, and seedling growth at nursery stage. Analysis of variance revealed significant differences among provenances in all studied attributes except root collar diameter after 4 months of growth. The provenance effect, as determined by broad sense heritability, was 71–98% for seed morphometric traits, 80% for germination capacity, 42% for germination energy, 57–58% for seedling height and 3–13% for root collar diameter. Seed weight showed a significant positive correlation with altitude and negative correlation with mean annual temperature of seed origin. Germination energy was significantly correlated with longitude and mean annual rainfall. Seedling parameters and geo-climatic variables of seed origin were fairly correlated. A significant intercharacter correlation was found between seed length and seed weight, between root collar diameter at the age of 4 months and seed length and weight, as well as between seedling height after 4 and 8 months of growth. It can be concluded that the observed patterns of variation will have implications for genetic resources conservation and tree improvement.