Sampling plans for aphids and their parasitoids in blueberry fields in Argentina

Densities of aphids (Aphis gossypii and A. spiraecola) and mummified aphids at different phenological stages of a blueberry crop were estimated for the purpose of developing sampling plans. Our data set comprised 99 samples taken during the period 2006–2008 in four fields in Buenos Aires Province, Argentina. Estimation of population density based on the proportion of sample units infested by individuals was investigated. We also calculated the minimum number of sample units to estimate the density of individuals on buds and buds + flowers using enumerative sampling. The relative precision of both methods was compared. Moreover, an enumerative sequential sampling protocol was developed. The presence–absence sampling plan gave density estimates with large variances (as measured by confidence intervals and large standard errors). The aggregation of mummies was similar on buds and buds + flowers, so the required number of sample units for density estimates was the same. Relative precision of estimates was much lower for the presence–absence sampling than the enumerative sampling, even at intermediate densities. An enumerative sequential plan would be the most appropriate and useful method in management plans for aphids and mummified aphids in blueberries.     

不同因素对兔眼蓝莓离体培养芽诱导效果的影响

[目的]为兔眼蓝莓的快速繁殖提供理论依据。[方法]以不同品种兔眼蓝莓为材料,取其不同部位外植体进行组织培养,研究植物品种、外植体类型（茎尖、带腋芽茎段、叶柄、叶片）、培养基种类（MS、改良MS、改良WPM）和植物生长调节剂（ZT、2ip,6-BA）对外植体芽诱导效果的影响。[结果]改良WPM、改良MS和MS培养基中带腋芽茎段的萌芽率分别为46．7％、36．7％和6．7％;改良WPM培养基中添加1～4mg／LZT或10～20mg／L2ip时,茎段的芽诱导效果较好;不同植物品种对外植体萌芽率无明显影响;改良WPM＋2mg／LZT培养基中茎段、茎尖、叶片和叶柄的萌芽率分别为86．7％、56．7％、3．3％和13．3％。[结论]兔眼蓝莓离体培养芽诱导的最佳外植体为茎段,最佳培乔基为改艮WPM＋1～4mg／LZT（或10～20mg／L2ip）。     

南烛叶多酚氧化酶最适提取条件的研究

[目的]深入探讨南烛叶多酚氧化酶(PPO)的酶学性质,对南烛叶PPO的最适提取条件进行研究。[方法]以南烛叶为原料,分别研究了交联聚乙烯吡咯烷酮(PVPP)添加含量、料液比、浸提时间和p H各因素对其提取的PPO酶活的影响。[结果]试验表明,适量南烛叶粉末,以料液比1∶15 g/m L,加入含9%PVPP(W/V)p H 7.6的柠檬酸-磷酸氢二钠缓冲液(0.1 mol/L),匀浆并于4℃下浸提9 h,过滤,滤液经冷冻离心(4℃,12 000 r/min,20 min)后得到酶活最高的PPO酶液(11 335 U/m L)。[结论]研究结果可为促进南烛叶的工业化应用提供参考。     

笃斯越桔离体培养及植株再生体系的建立

以笃斯越桔新生嫩芽为外植体,应用均匀设计法筛选其最适合的基部直接再生芽苗和生根的培养基,结果表明,最适合的基部直接再生芽苗诱导培养基为:DR+2-ip2.75 mg·L-1 +IAA0.10 mg·L-1,诱导率为99%;生根培养基:MS(改良)+IAA 1.00 mg·L-1 +Kt0.30 mg·L-1,生根率达98%;以再生植株的茎节为材料进行快繁的结果表明,在25 d的一个培养周期内增殖倍数平均达40以上,快繁培养基:MS(改良)+IAA 0.50～1.00 mg·L-1 +Kt0.30 mg·L-1+GA3 0.20 mg·L-1.建立了笃斯越桔的植株再生和快繁体系.     

乌饭树叶和乌饭营养成分的分析与评价

对野生植物乌饭树叶和乌饭的营养成分进行了分析。结果表明,乌饭树叶和乌饭中分别含有多种营养成分、丰富的矿物质元素和维生素,尤其是Vc、Fe、Mn、Se、Ca含量较丰富;至少含有17种氨基酸,氨基酸总量分别为9 027 mg·hg^-1和7 121 mg·hg^-1,其中蛋氨酸、组氨酸含量较高,7种人体必需氨基酸（EAA）总量分别为3 613 mg·hg^-1和2 462 mg·hg^-1,占氨基酸总量的40.02%和34.57%。必需氨基酸中苏氨酸、亮氨酸、异亮氨酸、蛋氨酸、苯丙氨酸、缬氨酸的构成比例基本符合联合国粮农组织/世界卫生组织（FAO/WHO）的推荐标准,鲜味氨基酸（DAA）总量分别为2 212 mg·hg^-1和2 202 mg·hg^-1。     

南方高丛蓝莓新品种‘新昕1号’

南方高丛蓝莓新品种‘新昕1号’是从美国引进的蓝莓优选系‘NC1074’בUS237’的人工杂交种子选育而成。叶色亮绿,椭圆形或卵圆形,叶渐尖,叶长4.82 cm,叶宽2.43 cm。花梗长0.90 cm,总状花序,每花序3 ~ 6朵小花。果实中等大小,平均单果质量1.22 g,坚实,蒂痕小,深蓝色,味酸甜可口,果粉厚。在南京地区6月上旬成熟。丰产性强,对江苏省南部夏季高温多湿气候和粘重土壤有较强的适应性。     

乌饭树的地理分布及潜在分布区分析

利用Bioclim模型,结合354个乌饭树地理分布点以及19个气候因子,对乌饭树在我国的潜在分布区和适宜等级进行了预测。结果表明:潜在分布区的预测结果与实际分布点吻合较好,其适生区(适宜度≥5%)主要为广西、广东、福建、浙江、江西东南部、湖南西部及贵州东部等地区;湖南、江西南部与广东、广西北部交界处的南岭地区及福建中部山地等地区为乌饭树的最适生区(≥20%)。ROC曲线的AUC值为0.819,表明预测结果很准确。极端低温、最干季降雨量、极端高温、温差是影响乌饭树分布的主要水热因子,最适宜区气候参数为:年平均温为14.7—23℃,适宜越冬的年极端低温为-3.1—13.4℃,年降雨量为948.8—1988.4mm,最干季降雨量为54.6—201mm,分布的最适宜海拔范围为3—806m之间。气候变暖将使得乌饭树潜在最适分布区面积显著缩小,现有最适生境位置发生改变。     

兔眼蓝莓组培体系建立及多倍体诱导研究

蓝莓具有较高的营养价值和经济价值,但其繁殖速度慢、果实较小、采摘成本高,优化现有的蓝莓品种具有良好的发展前景。本文以兔眼蓝莓灿烂幼嫩茎段为试验材料开展组织培养研究,采用不同的培养基配比激素以及设置不同浓度用以研究出最适合兔眼蓝莓灿烂生长的、稳定的、可重复性强的培养基配方,建立叶片再生体系,并采用秋水仙素培养基添加法对其进行诱导。在无菌条件下切取由叶片再生形成的长势较好苗的带叶茎尖(长约0.5 cm),接种到秋水仙素浓度为10、20、30、40、50、60 mg/L的6种培养基中。结果表明,最适兔眼蓝莓灿烂腋芽启动培养基是配方WPM+0.005 mg/L NAA+2.0 mg/L ZT+20 g/L蔗糖+6 g/L琼脂,诱导效果最佳,发芽率高达93%以上;取离体叶片再生芽苗的茎尖进行共培养诱导多倍体,50 mg/L秋水仙素处理50 d和60 mg/L秋水仙素处理30 d或40 d时,诱导植株变异的效果最佳,变异率均达30%以上。     

In vitro induction of the amphiploid in interspecific hybrid of blueberry (Vaccinium corymbosum × Vaccinium ashei) with colchicine treatment

Amphiploids were produced from pentaploid hybrids between Vaccinium corymbosum (4x) and Vaccinium ashei (6x) by colchicine treatment. Seeds of each parental species and those obtained by the interspecific crossing were treated with colchicine at 0, 500, 1000 and 2000 mg/l for 7 days, and the ploidy level of the seedlings was determined with flow cytometry. Either amphiploid (10x) or ploidy chimera (5x + 10x) was obtained from interspecific hybrid seeds treated with all colchicine concentrations, while no chromosome-doubled plants were obtained from both parents. Cross direction in interspecific hybridization affected the results of colchicine treatment and amphiploids were obtained only when V. corymbosum was used as the seed parent. In this cross, 17–25% of the seedlings turned to be amphidiploids or ploidy chimeras by treating with 500 mg/l colchicines for 7 days. These results indicate that susceptibility to colchicine may increase in the interspecific hybrid compared with the parental species but only when V. corymbosum was used as female parent.