Chufa (Cyperus esculentus L. var. sativus boeck.): An unconventional crop. studies related to applications and cultivation

Tubers ofCyperus esculentuswere an important food in ancient Egypt. In Spain the tubers are used to make a beverage named horchata, and are also consumed as fresh after soaking. In other countries tubers are used in sweetmeats or uncooked as a side dish. New products obtained can enhance the interest in this crop: as a source of dietary fiber in food technology; as a high quality cooking/salad oil or as biodiesel fuel; as caramel to add body, flavor or color to other products; as a source of starch; as an antioxidant-containing food, etc. The results of a twenty-year research program on nutrition, fertilization, lodging control, planting date, soil texture and use of herbicides are shown. Three cultivars (‘Ametlla Bonrepos’, ‘Gegant Africana’, and ‘Llargueta Alboraia’) are selected and characterized using horticultural and morphological traits, the chemical composition of tubers and horchatas, and the RAPD technique.     

不同水稻品系幼苗对砷（As）的耐性、吸收及转运

利用琼脂培养基模拟水稻生长的厌氧环境,研究了As对不同水稻品系幼苗生长的影响以及As在其体内的积累及转运特性.结果表明,不同浓度(0～4.0mg/L)的As对供试水稻品系根部干物质积累无显著影响(P>0.05).杂交稻与糯稻的地上部干物质积累随基质中As浓度的增加呈减小趋势,但低剂量的As(0.5mg/L)促进常规稻的生长.水稻地上部的As积累量随基质中As浓度的升高总体均呈增加趋势.水稻根系对As具有较强的吸收与累积能力.水稻根部As的积累量为156.31～504 03mg/kg,占总As含量的63.40～81.90%,远远高于其地上部As的积累量.相比于其它两个品系,糯稻的生物量积累高,耐性指数较大,根部及地上部对As的积累量较低,因此更适合种植在As污染土壤.     

高温对水稻叶片蛋白质表达的影响

为明确高温对耐热性不同水稻品种叶片蛋白质表达的影响,以耐热性不同的2个籼稻品种双桂1号(不耐热)和黄华占(耐热)为材料,分别于苗期、减数分裂期及抽穗(始穗后0—10d)和灌浆早期(始穗后11—20d)进行高温处理,之后取材并采用双向凝胶电泳技术研究高温对不同水稻品种叶片蛋白质表达的影响。结果表明,高温胁迫导致叶片中蛋白质的变化呈4种状况:新蛋白质的产生,一些蛋白质表达量上调,一些蛋白质的表达被抑制,一些蛋白质表达量下调。蛋白质表达变化在两品种以及4个处理时期的表现不同,总体表现为在热敏感品种中表达谱发生变化的蛋白质总数高于耐热品种。质谱分析表明,差异蛋白质主要涉及光合作用和信号转导,该类蛋白质在热敏感品种中表现为不表达或表达量下降,而在耐热品种则表现为有新诱导的蛋白质的产生或表达量上调,表明参与光合作用和信号转导的蛋白质在水稻耐热机制中发挥了重要作用。     

Differential responses to feeding by the tomato/potato psyllid between two tomato cultivars and their implications in establishment of injury levels and potential of damaged plant recovery

An invasive new biotype of the tomato/potato psyllid （Bactericera [Paratrioza] cockerelli [Sulc.]） （Homoptera： Psyllidae） recently has caused losses exceeding 50% on fresh market tomatoes in western North America. Despite these extensive losses, little is known regarding the threshold levels at which populations must be suppressed in order to prevent economic losses. A series of experiments were therefore designed using combinations of two common tomato cultivars （QualiT 21 and Yellow Pear）, five pest-densities （0, 20, 30, 40 and 50 nymphs/plant）, and three feeding-duration （5 days, 10 days, and lifetime） treatments to test the relative importance of pest density, feeding period, and cumulative psyllid-days to establish economic threshold levels for psyllids. The cultivars differed considerably in their response to the toxin injected by the psyllid nymphs. ‘Yellow Pear＇ plants could recover from feeding by up to 40 nymphs for as long as 10 d, whereas ‘QualiT 21＇ plants were irreparably damaged by densities of 20 nymphs feeding for only 5 days. On ‘Yellow Pear＇, all plant measurements such as the number of yellow leaves and plant height were significantly better correlated with cumulative psyUid-days than with either pest density or feeding duration. On ‘QualiT 21 ＇, all plant measurements other than the number of yellow leaflets and leaves were significantly better correlated with pest density than with feeding duration or cumulative psyUid-days, and pest density was a better predictor of psyUid damage. Potential reasons for the variable responses between cultivars and the implications for psyllid sampling and integrated pest management are discussed.     

NaCl胁迫对黄瓜幼苗体内K+、Na+和Cl-分布的影响

采用营养液水培,以2个耐盐性不同的黄瓜品种为材料,研究了不同浓度NaCl处理下幼苗植株体内K 、Na 和Cl-在器官间的区域化分布及其吸收和运输特性的变化。结果表明:NaCl胁迫下,黄瓜植株体内K 含量下降,Na 和Cl-含量升高,变化幅度随NaCl浓度的升高而增大;不同器官间,茎中Na 和Cl-含量最高,上位叶中Na 和Cl-含量最低、K 含量下降幅度最小。与耐盐性较弱的“津春2号”相比,耐盐性较强的“长春密刺”根向茎运输的SK,Na值较高,根系对Na 的截留作用较强,茎向上位叶运输的SK,Na和SCl,Na值均较高,叶片中K 含量下降幅度较小,K/Na和Cl/Na比值均较高,功能叶中盐分离子尤其是Na 积累较少,植株生物量较高。说明根系对Na 的截留能力较强且向上位叶运输Na 的选择性较低,是“长春密刺”耐盐性较强的主要原因之一。     

灵芝两个无孢品种中水提物成分分析及免疫活性比较

龙芝2号和鹿角灵芝均为赤芝的栽培品种,且在生长发育过程中均不产生孢子。目前,尚缺乏对两者化学成分和药理活性的系统比较研究。本研究以灵芝两个无孢品种——龙芝2号和鹿角灵芝为原料,研究对比两者子实体水提物成分差异及免疫活性的强弱。采用化学及仪器分析相结合的方法,分析两者水提物中的多糖得率、含量、重均分子量分布特征及核苷、蛋白质、氨基酸含量差异,并研究了灵芝两个无孢品种水提物样品刺激RAW 264.7细胞释放NO活性。结果表明,两者多糖得率及含量差异不大,但龙芝2号中重均分子量分布范围较广,多糖分子量较大,其含有3种多糖,分子量分别为2.021×10⁶、1.802×10⁶和4.825×10⁵,而鹿角灵芝中仅含有1种多糖,分子量为1.589×10⁴;两者中含有的核苷种类相似,但各核苷的含量存在差异;鹿角灵芝和龙芝2号中蛋白质含量分别为10.70%和10.32%,两者均不含有组氨酸,蛋氨酸在两者中含量均较高,分别达到2.556%和2.591%。从鹿角灵芝和龙芝2号中得到的水提物样品均具有体外刺激巨噬细胞释放NO的活性。     

新经济植物黑莓的引种

黑莓（Ｒｕｂｕｓｓｐｐ．）是第三代新兴的小果类果树之一。江苏省植物研究所于１９８６～１９８８年从美国引进了７个黑莓品种,从中选出适合江苏地区栽培的Ｈｕｌｌ,Ｃｈｅｓｔｅｒ,Ｂｌａｃｋｓａｔｉｎ３个品种,并已初步推广。田间试验对３个品种的发枝习性、开花结果习性和产量构成等进行比较。Ｈｕｌｌ单株产量最高,果实最大,ＢｌａｃｋＳａｔｉｎ单株产量最低,果实最小。但若种植密度适宜,３品种均能达到高产。     

间作缓解蚕豆连作障碍的根际微生态效应

通过田间小区试验,研究了3个品种蚕豆(92-24、云豆324、凤豆6号)与小麦间作对蚕豆产量、枯萎病病情指数、根际镰刀菌数量、根际真菌代谢功能多样性和土壤酶活性的影响。结果表明:与单作蚕豆相比,云豆324与小麦间作(YD324/W)和凤豆6号与小麦间作(FD6/W)处理均显著提高了蚕豆地上部干重、籽粒产量和百粒重。YD324/W和FD6/W处理使蚕豆枯萎病发病初期病情指数分别降低57.14%和41.67%,镰刀菌数量分别降低32.06%和29.88%,而92-24与小麦间作(92-24/W)处理蚕豆产量、枯萎病病情指数和镰刀菌数量与单作蚕豆均无显著差异。YD324/W和FD6/W处理显著提高了蚕豆根际真菌的多样性指数和丰富度指数,并使蚕豆根际真菌的AWCD值分别比单作蚕豆提高了61.75%和46.49%;YD324/W和FD6/W处理明显改变了蚕豆根际真菌的群落结构。而92-24/W处理对蚕豆根际真菌的多样性指数、丰富度指数和AWCD值均无显著影响,也未明显改变真菌的群落结构。不同发病时期,YD324/W和FD6/W处理均显著提高了蚕豆根际土壤的蔗糖酶、脲酶和过氧化氢酶活性;而92-24/W处理蚕豆根际蔗糖酶、脲酶和过氧化氢酶活性与单作蚕豆均无显著差异。总之,小麦与不同品种蚕豆间作改变了蚕豆根际的真菌群落结构,提高了蚕豆根际真菌的活性、多样性和丰富度,提高土壤酶活性并改善蚕豆生长,增加了蚕豆产量。表明小麦与蚕豆间作改善了根际土壤的微生态环境,降低了镰刀菌的数量,缓解了蚕豆连作障碍,但蚕豆品种的差异影响间作控病效果。     

Variation in activity of root extracellular phytase between genotypes of barley

Barley genotypes grown in nutrient solution under P nutrient stress and sterile conditions were compared in activity of root-associated and root-released extracellular phytase. The activity of root-associated phytase of all genotypes was about 10 times higher than that of root-released phytase and the genotypes performed differently with regard to the activity of the enzymes. The winter barley genotype, Marinka had the highest activity of root-associated extracellular phytase which differed significantly from Alexis and Sonate, but not from Regatta. Alexis showed the lowest activity of root-released extracellular phytase which differed significantly from those of Marinka and Regatta, but not from Sonate. Generally, there was a significant correlation between the activity of root-associated and released extracellular phytase.     

Effects of source/sink manipulation on net photosynthetic rate and photosynthate partitioning during grain filling in winter wheat

Source-sink relationship, which was influenced by both genotype and environmental factors, contributed to the variation in photosynthesis and photosynthate partitioning of wheat. Source reduction by partial defoliation increased leaf net photosynthetic rate (PN), and sink reduction decreased PN of irrigated wheat. However, the change in PN varied among genotypes. Source reduction enhanced photosynthate translocation into grain in irrigated wheat. However, the enhancement was more evident in cv. Lumai 215953 than incv. Lumai 15. Sink reduction had little effect on the translocation of photosynthate into grain in cv. Lumai 15, but decreased the translocation of photosynthate into grain and increased it into stem in cv. Lumai 215953. In rainfed, non-irrigated wheat, the source or sink manipulation influenced PN only slightly. The source reduction decreased the partitioning of photosynthates into the upper parts (including grains) of plant. However, very little effects of sink reduction on the production of photosynthates occurred in rainfed wheat. This showed that grain sink size was not a factor limiting the production of photosynthates, but controlled the partitioning of photosynthates. Sink reduction decreased photosynthate translocation into grains, and increased it into upper parts of rainfed wheat plant. This revised version was published online in July 2006 with corrections to the Cover Date.