Structure identification of five unknown dilipo-alkaloids extracted from processed tuber of Aconitum carmiechaeli by electrospray ionization tandem mass spectrometry

The alkaloids in processed aconite tuber of Aconitum Carmiechaeli were studied, and five novel alkaloids in extract from processed aconite tuber were found. The first step involved the use of electrospray ionization mass spectrometry (ESI-MS), and then multi-stage tandem mass spectrometry (MSn) was used to provide structural information. Based on their MSn spectra, the structures of the five novel compounds were elucidated to be C3,C8-difatty acid esters of mesaconitine, aconitine and 10-hydroxyaconitine.

云南吕合中新世木贼属草问荆比较种及其古生态学研究

位于我国西南边陲的云南省今天以丰富的植物种类、复杂的植被类型，被誉为“绿色明珠”和“植物王国”，其现今格局的形成无疑是长期历史演化的结晶。探讨其植物区系成分的由来、植被演替的规律及其与环境的关系已经成为研究的热点问题。 新生代是云南植物王国形成和环境演变过程中的关键地质时期。本论文以新生代晚第三纪中新世吕合地区植物群为研究的切入点，对其中的木贼属（Equisetum L.）化石做了深入研究。 木贼属为早期陆地维管植物楔叶类唯一的现存代表，过去报道和研究的化石记录多集中在古生代和中生代，新生代的较少。 本文首次报道云南吕合中新世地层中发现的以地下根状茎和块茎形式保存的木贼属草问荆比较种（E. cf. pratense Ehrhart）。化石根状茎分明显的节和节间， 节部簇生1-4 串串珠状的块茎（每串块茎数目2-4 个），单个块茎椭圆形、圆球形、卵形或纺锤形，通常位于串珠末端的块茎顶端较尖。 木贼属现存两亚属：问荆亚属（8 个种，气孔与表皮齐平，地上茎一年生， 通常分枝，孢子囊穗顶端钝）和木贼亚属（7 个种，气孔凹陷于表皮，地上茎宿存，通常不分枝，孢子囊穗顶端尖）。问荆亚属中，除溪木贼（E. fluviatile L.） 和E. bogotense Kunth 外，其余6 个种都有块茎，而从未在木贼亚属中发现过块茎。具块茎的问荆亚属6 个种中，仅发现草问荆有2-3 个串联的块茎，其余种均为单个块茎。鉴于吕合发现的化石根状茎上着生块茎之特征和现代草问荆的情形一致，表明二者之间亲缘相近，故将吕合化石标本鉴定为草问荆比较种。 前人在北美、欧洲和亚洲的早白垩世到第三纪地层中，报道过14 种具根状茎和块茎的木贼类化石，其中具串珠状块茎的仅5 种。这些化石种与吕合标本有明显区别，如美国怀俄明州始新世的E. haydenii Lesquereux 根状茎的节部收缩，块茎有分枝。美国蒙大纳州渐新世至中新世的E. cf. arcticum Heer 和中国吉林始新世的E. hunchunense Guo 块茎在根状茎节上轮生。尽管据报道加拿大白垩纪E. perlaevigatum Cockerell 和辽宁北票早白垩世Equisetites longevaginatus Wu 有串珠状块茎结构，但原文提供的照片显示却只有单个块茎。 根据将今论古的原理，似可将化石的现存最近亲缘种草问荆的生境和物候调查结论，推演到发现草问荆比较种的云南吕合中新世地点及相应层位上。这样，不仅可以推测当时环境湿润，而且化石沉积的时间应为块茎形成的秋冬季节。结合前人在该产地发现喜热的亚热带成分壳斗科青冈属、栲属、金缕梅科枫香属等花粉和喜湿的桦木科桤木属花粉、杉科落羽杉型木以及红杉属的枝叶和球果，表明云南吕合中新世植被类型为常绿落叶阔叶混交林，气候类型为温暖湿润的亚热带气候。

保水剂对宁南山区马铃薯产量及土壤水分利用的影响

在宁南半干旱黄土丘陵区探讨大田施用PAM、沃特保水剂对马铃薯产量和土壤水分利用的影响。结果表明:PAM、沃特均可促进马铃薯生长、提高块茎产量,其中PAM 9.0 kg/hm2(P3)和沃特15 kg/hm2(W1)、沃特30kg/hm2(W2)、沃特60 kg/hm2(W3)处理马铃薯生物量和块茎产量显著高于CK(P<0.05),增产效果最明显。幼苗期、块茎形成期和块茎生长期各处理耗水量无显著差异,淀粉积累期CK耗水量极显著高于施用保水剂处理(P>0.01)。保水剂处理耗水量随着马铃薯生物量的增加而增大,降雨对土壤水分的补充随生物量的增大而减少。利用有序聚类分析得出,淀粉积累期降雨对土壤0~60 cm的水分储量有明显的补充,施用PAM和沃特两种保水剂,0~140 cm各层土壤储水量恢复相近,而140 cm以下土层沃特的恢复能力优于PAM,平均每20 cm土层储水量较PAM高6.2 mm。随着PAM施用量的增加水分利用效率提高,沃特保水剂则相反。沃特15 kg/hm2和PAM 9 kg/hm2处理水分利用效率、水分产出效率最高。通过对马铃薯产量和水分利用特征得出,PAM的用量为9 kg/hm2、沃特15kg/h...

Effect of gamma-ray radiation on physiological, morphological characters and chromosome aberrations of minitubers in Solanum tuberosum L.

Purpose: To investigate the effects of gamma-ray radiation on the physiological, morphological characters and chromosome aberrations of minitubers. Materials and methods: Minitubers of one potato cultivar, 'Shepody', were irradiated with 8 doses of gamma-rays (0, 10, 20, 30, 40, 50, 60, 70 and 80 Gy [Gray]) to investigate the effects of radiation on emergence ability, plant height and root length, morphological variations, chromosome aberrations, M-1 (first generation mutants) tuber number and size of minituber plants. Results: Compared with the non-irradiated controls, the whole period of emergence was prolonged by 10-15 days for minitubers treated with gamma-ray radiation, but low doses of radiation (10, 20 and 30 Gy) promoted the emergence percentage of minitubers. With an increase in radiation dose, the emergence percentage, plant height and root length of minituber plants were significantly inhibited at 40 and 50 Gy. No emergence occurred at 60 Gy and higher doses. After radiation, a series of morphological variations and chromosome aberrations appeared in minituber plants. Radiation with 20 Gy promoted tuber formation, and the average number and diameter of M-1 tubers per plant were significantly increased over the control by 71% and 34%, respectively. Conclusion: Low doses of radiation (10-30 Gy) might be used as a valuable parameter to study the improvement of minitubers by gamma-ray radiation treatment.