摘心对垦鲜枣1号生长发育特性 及光合特征参数的影响

为解决密植枣园易造成果园过度郁闭结果能力下降,果实品质较差等问题以新疆北疆地区主栽品种 垦鲜枣1 号为试材对矮密栽培模式下红枣进行摘心试验结果表明：不同摘心处理对枣头长度(F=9.218)二次枝长 度(F=3.755)以及Pn、E、C、InTCO2影响差异极显著,不同处理间枣吊长度(F=0.647)差异不显著,枣头粗度、枣头节间长 度等指标存在显著差异,通过对不同摘心处理生物量调查与光合特征参数的分析,得出矮化密植枣园优化的摘心处 理技术为矮化密植枣园的树体调控提供理论依据。     

不同授粉方法对百合不同杂交组合结实的影响

采用常规柱头授粉、切割花柱授粉和柱头涂抹0.1%NAA 3种授粉方法,以4个杂种系的品种和3个野生种为材料,分别进行系内、系间杂交试验,旨在研究不同授粉方法对百合不同杂交组合结实情况的影响。试验结果表明：在系内杂交试验中,采用常规柱头授粉方法对东方百合系内不同杂交组合的效果最好,14个杂交组合中,尤其以杂交组合Pink Expression（O1）×Rain Dance（O8）的结实率最高,其子房膨大率、蒴果结实率和种子有胚率分别为86.36%,72.73%和32.08%。在系间杂交试验中,切割花柱授粉并非都能提高结实率,在有些组合中,切割花柱授粉方法不仅不能克服其杂交障碍,反而降低其结实率,如对于组合Shocking（OT3）×Cocar D’Or（O4）,采用切割花柱授粉方法使蒴果结实率从66.67%降低到50%,降低了16.67%。在以野生百合为父本的远缘杂交试验中,组合Bonsoir（LA5）×L.pumilum（W2）采用柱头涂抹0.1%NAA授粉方法结实率最高,其蒴果结实率和种子有胚率分别为77.78%和10.85%。     

A comparison of the gelling of isubgol,agar and gelrite on in vitro shoot regeneration and rooting of variety Samsun of tobacco (Nicotiana tabacum L.)

Agar is being used to solidify media for plant tissue culture since long. Both purity and type of agar or gelling agent influence the behaviour and growth of tissues in culture. The study using leaf disc explants of variety Samsun of tobacco compares adventitous shoot regeneration on 0.5 cm × 0.5 cm leaf discs cultured on MSD4X2 medium and rooting on MSO medium gelled with different blends of agar–isubgol, gelrite–isubgol, phytagel–isubgol or isubgol singly. It was found that irrespective of some problems associated with isubgol gel, the maximum number of shoot per explant were recorded on MSD4X2 medium gelled with 7 g/l isubgol. The longest shoots were recorded on MSD4X2 medium gelled with 9 g/l isubgol. Likewise, the highest number of roots were also recorded on MSO medium gelled with 7 g/l isubgol. For a given quantity of a medium, agar, gelrite/isubgol blends are very cheap compared to agar used singly. Moreover, blends of agar/isubgol, gelrite/isubgol gelled at low temperatures indicated safe use of these gels for heat labile substances in genetic transformation or tissue culture experiments. The results emphasized the potential of the isubgol used singly or in combination with agar and gelrite for economic commercial application, replacing the costliest, though not indispensable, gelling agent agar.     

4种药剂对红火蚁田间防治效果评价

以工蚁减退率和活动蚁巢减退率为指标,评价了10%高效氯氰菊酯、1.8%阿维菌素、噻虫?氟氯氰、0.1%舒绝杀蚁饵剂对红火蚁的田间防治效果。结果表明,1.8%阿维菌素防治效果一般;10%高效氯氰菊酯持效性较好、速效性一般;噻虫?氟氯氰速效性和持效性均较好,但安全性较差;0.1%舒绝杀蚁饵剂在对活动蚁巢防效和工蚁防效上,均表现出较好的持效性,且使用方法简单,对环境友好,是一种较为理想的红火蚁田间防治药剂。     

0.1％氯吡脲可溶性液剂对西瓜的安全性评价

通过在湖北和浙江两地进行氯吡脲田间药效和残留试验,为安全合理使用该药剂提供依据.试验用0.1％氯吡脲可溶性液剂有效成分量10、20、30 mg/L浸泡瓜胚2s,坐果和采收后测定药效和药物残留.结果表明,0.1％氯吡脲可溶性液剂在西瓜上施用可以提高坐果率、促进增产,对品质无不良影响,药后30d所有西瓜样品中均未检出氯吡脲残留.证明氯吡脲在试验剂量范围内对西瓜安全,可以在西瓜生产中应用.     

不同季节使用0.1%氯吡脲可溶性液剂对西瓜*产量和可溶性固形物含量的影响

研究0.1%氯吡脲可溶性液剂有效成分量10mg/L、20mg/L、30mg/L、40mg/L和50mg/L对海南不同季节栽培西瓜产量和可溶性固形物含量的影响。结果表明,冬季使用0.1%氯吡脲可溶性液剂处理可以提升西瓜果实含糖量改善品质,但不利于产量的提高;春季则对西瓜果实正常生长无影响,在海南西瓜生产上可使用0.1%氯吡脲可溶性液剂,并替代人工辅助授粉。     

0.1%阿卜答GR在水稻上应用效果分析

阿卜答是一种新型高效的植物生长调节剂,在水稻上施用0.1%阿卜答GR,苗期促进植株矮化、增加水稻的根长、提高叶绿素含量、缩短水稻第三叶片的长度;成株期提高结实率、增加水稻的有效穗数、穗长增加、千粒重增加等,综合累加效应明显,具有增产的潜力。     

Applied Mn extracted by four methods correlated with Mn concentrations in soybean leaf tissue on a southeastern soil

Abstract

Four extractants for soil Mn were compared for their sensitivity to changes in Mn availability caused by rates and sources of added soil Mn and soil pH variations. Their ability to extract amounts of Mn correlated with plant Mn concentrations was also determined. Two field experiments were conducted on a sandy, high water table soil (Ultic Haplaquod‐Arenic Plinthaquic Paleudult) which included 5 Mn rates, 4 Mn sources and 3 soil pH levels. Soybeans [Glycine max (L.) Merr. cultivar Ransom] were grown and leaf tissue and soils sampled at the late pod‐fill stage. All four extractants separated the high‐ Mn rates, but the small exchange method did not separate the low Mn rates. Few differences were observed among extractants due to Ma sources. The DTPA method was the only procedure to correctly distinguish soil pH levels by showing decreasing extractable Ma with increasing soil pH. Including pH in multiple regressions significantly increased the plant Mn‐soil Mn correlation coefficients. The DTPA method and the 0.1N H₃PO₄ method had the highest correlation coefficients and the double acid method the lowest. The small exchange method was intermediate. Considering all the results, the DTPA was the most promising method for extracting Mn from this sandy, southern Coastal Plain soil.     

应用Beverton-Holt单位补充量产量模型估算东海区带鱼生物学参考点F_(0.1)和F_(MSY)

应用Beverton-Holt单位补充量产量模型,估算东海区带鱼生物学参考点F0.1、FMSY及其对应的MSY、Y0.1,并探讨了开捕年龄tc与上述生物学参考点的关系。结果表明,在当前的开捕年龄条件下,带鱼的F0.1比FMSY降低了31.71%,而单位补充量产量Yw/R只下降了4.46%;F0.1、FMSY随tc的提高而不断增大;若以MSY/R为管理目标,当tc为3.08龄时,Yw/R取得最大值329.41 g,可承受较大的捕捞强度;若以Y0.1/R为管理目标,当tc为2.50龄时,Yw/R取得最大值281.32 g,而F0.1仅为0.66。