马铃薯脱毒种薯标准化生产技术研究——Ⅰ.不同密度栽培对块茎大小、单株结薯及产量的影响

试验利用高海拔地区的气候特点和土壤肥沃疏松条件 ,将“鄂马铃薯 3号”脱毒试管苗直接进入田间土床培育 ,在高密植栽培条件下 ,生产标准种薯。经 9个处理的试验结果表明 :随着种植密度的增加 ,单位面积上的块茎数、无效薯增加 ,大薯率降低。3～ 5 0 g结薯率最佳处理是F、H和C ,分别占83 5 0 %、83 81%和 84 5 0 % ;10 ～ 30 g结薯率最佳处理是E和F ,分别占总数的 4 3 96 %和 4 6 86 % ,产量最佳处理是E和F ,分别为 15 0 0kg/ 6 6 7m2 和 15 83kg/ 6 6 7m2 ,各处理间差异达极显著水平。单位面积结薯数与单位面积移栽株数呈极显著正相关 ,y =196 6 6 + 0 98x(r=0 98 ) ;单株结薯数与单位面积移栽株数呈极显著负相关 ,y=2 89- 0 0 0 2 2x(r =- 0 81 )。     

马铃薯脱毒种薯标准化生产技术研究——Ⅱ不同时期栽培对块茎大小、单株结薯及产量的影响

试验在海拔 190 0m处的自然条件下 ,将鄂马铃薯 3号脱毒试管苗直接进入大田土床培育、切顶扦插繁殖 ,以同一密度 ,不同时期将土培扦插苗移栽到试验区内 ,生产种薯。试验结果表明 ,从 5月 2 8日至 6月 2 6日移栽的土培扦插苗 ,5 g以上块茎重量占 94 %以上 ,其中 ,10 0～ 15 0 g块茎重量占 17 6 7%～ 19 5 5 % ,产量达 14 4 5～ 180 3kg/ 6 6 7m2 ,处理间差异极显著。 6月 6日移栽的单株结薯数平均 4 0 5个 /株 ,尔后随移栽时期的延迟 ,单株结薯个数呈缓慢下降趋势。     

提高雾化栽培马铃薯微型薯结薯能力的初步研究

用 3种处理方法 ,下放植株 ,激素 (CCC) ,剪尖对雾化栽培室内的脱毒苗进行随机区组处理。结果表明 :激素和剪尖对叶面积系数 (LAI)、株高、茎粗等营养器官生长特征影响一致 ,可用剪尖替代激素促进形态建成 ;下放植株可极显著促进根系发育 ,促使腋芽向匍匐茎转化 ,可极显著提高微型小薯的产量 ;同时 ,相关分析表明 ,LAI与单株薯数呈极显著正相关 (r =0 874 8 ) ;根系体积与单株薯数显著相关 (r=0 82 0 1 ) ,与单株匍匐茎数极显著相关 (r =0 8770 )。     

马铃薯脱毒试管苗无土栽培高产机理研究

在防虫网室中无土栽培马铃薯脱毒试管苗生产微型薯。用 9次剪尖和 8次培土的办法 ,180d平均单株结薯达 2 12 8个 ,2 10d商品粒数 (≥ 1g)达 158 2个 ;且剪尖和培土的次数与匍匐茎数、腋芽枝数和单株结薯个数有正相关关系 ,后两者均达极显著水平r1=0 90 2 3,r2 =0 94 70     

不同栽培密度对商薯 8 号农艺性状和经济性状的影响

本研究采用田间试验方法，研究栽培密度对商薯 8 号农艺性状与经济性状的影响。结果表明：T4（60 000 株 /hm2 ）处理的薯块干物质分配率最高，与 T1（37 500 株/hm2 ）相比，150 d 时 T4 处理薯块干物质分配率显著增加 16.14%。 T4 处理的鲜薯干物率明显高于其他 3 个处理。T1 处理的单株薯重、单株最大薯重、单株蔓重显著高于 T2（45 000 株 /hm2 ）、T3（52 500 株/hm2 ）和 T4 处理，T2 处理的 T/R 值显著高于 T3、T4 处理。T3 处理的商品薯产量及商品薯率最 高。生产上选择 52 500 株/hm2 的栽培密度较为适宜。研究结果为商薯 8 号合理栽培提供理论依据。     

马铃薯晚疫病水平抗性优良品系“395049.62”栽培技术研究

对CIP马铃薯晚疫病水平抗性优良高代无性系395049.62设计了微型薯、普通薯育芽带薯移栽,667m2种植4000株、6000株二种密度,施用尿素15kg、20kg二次追施的三因素、二水平栽培试验。结果表明,在试验设计范围内,品系395049.62产量以微型薯育芽带薯移栽、667m2种植6000株、追施尿素15kg两次处理最高;大中薯率以微型薯育芽带薯移栽、667m2种植4000株、追施尿素20kg两次处理最高,其次是微型薯育芽带薯移栽、667m2种植4000株、追施尿素15kg两次追施处理。     

微型薯不同生产方式对合格薯的影响

为了探索微型薯不同生产方式对合格薯的影响,以‘夏波蒂’脱毒苗为试验材料,共设计了5个处理,分别为切头0、1、2、3和4次。结果表明,试验所设处理间切头1次原植株合格薯数最高,值为1.1个/株,不切头原植株合格薯数为0.9个/株,随切头次数增加原植株单株合格薯数呈递减趋势,从产量分析结果来看,脱毒苗切头1次与其他几个处理相比差异均达极显著水平,脱毒苗不切头与切头2次差异不显著与切头3次、4次呈极显著差异。     

氮肥基追肥比例对马铃薯微型薯生产的影响

为探讨马铃薯微型薯合理的氮肥施肥方式,以‘早大白’马铃薯脱毒试管苗为材料,在温室内进行了氮肥不同基施和追施比例对马铃薯微型薯生产影响的试验。结果表明:在施氮肥量为纯氮105 kg/hm2条件下,单株结薯方面,基追比为5:2时,单株结薯最多,全部做基肥的处理,单株结薯最低;单粒重方面,基追比为2:1时,单粒重最大,全部追肥的处理最低。可见氮肥基施和追施配合有利于提高单株结薯率及平均单粒重。因此,微型薯生产重视氮肥基施同时配合追施比较符合移栽的试管苗对氮肥的吸收规律。     

缓控释肥施用对旱作区全膜马铃薯生长及产量的影响

为明确缓控释肥的施用对全膜马铃薯关键生长指标及产量的影响,分别在高(H)、中(M)和低(L)3种施肥条件下进行了2种不同施肥方式即集中沟施(F)与表层撒施(B)的田间试验。结果表明,缓控释肥施肥水平对旱作全膜马铃薯的主要生长指标(除茎粗)、产量及商品薯率的影响显著,在施用900 kg/hm~2的高肥水平时,其沟施处理的马铃薯产量、大薯率和商品薯率均达到最大,分别达43 609 kg/hm~2、72.1%和92.7%。施肥方式对马铃薯单株结薯数、大薯数、单株薯重、大薯重、产量和大薯率影响显著,且在3种施肥水平下,集中沟施(F)处理的马铃薯产量、大薯率和商品薯率均高于表层撒施(B)处理,其中在高肥水平下HF处理较HB处理平均增产达2 835 kg/hm~2,增产率为6.9%。施肥水平×施肥方式对马铃薯各生长指标和产量影响均不显著。综合来看,缓控释肥在较高水平的施肥(900 kg/hm~2)条件下,集中沟施处理(HF)有利于旱作区全膜马铃薯产量的提高。     

脱毒马铃薯试管苗直接移栽结薯研究

在日光温室中 ,以蛭石为无土栽培基质 ,脱毒马铃薯试管苗直接移栽 ,生产微型薯 ,通过炼苗提高成活率 ,调控温湿度促壮苗 ,及时培土提高结薯率 ,水肥适宜促薯块膨大。平均单株结薯率达到 4 2粒 株 ,由于长期生长 ,单薯重增加到 6 8g ,提高了脱毒薯 1～ 2个等级 ,试管苗直接结薯不仅解决了扦插伤口二次污染的问题 ,而且产量提高了 4 9 6 9% ;效益提高了 16 9 15 %。     

兜兰离体快繁技术研究进展

由于生境破坏和人工过度采挖及繁殖的障碍,兜兰已是世界上最濒危的植物物种之一,所有野生种均被列入《濒危野生动植物种国际贸易公约》附录I而被禁止交易。突破其种苗繁殖技术瓶颈有利于兜兰种质资源的保护和可持续利用。本文对兜兰属植物无菌播种、共生萌发和组织培养技术等离体快繁技术的进展进行综述,并提出了目前存在的问题和解决方法,以期为兜兰属植物离体繁殖技术的深入研究和优质种苗的规模化生产提供参考。     

High variation in frequency of infection by endophytes in cultivars of meadow fescue in Finland

Systemic and asymptomatic Neotyphodium fungal endophytes infect numerous species of the Poaceae. The frequencies of Neotyphodium endophyte infection in Finland were investigated among and within seven Nordic cultivars of meadow fescue, Schedonorus pratensis (Huds.) P. Beauv., which is a widely grown pasture and forage grass species in Scandinavia. The cultivars were Kasper, Salten, Antti, Fure, Ilmari, Inkeri and Kalevi. Frequencies of infection of cultivars varied from endophyte-free cultivar Fure to highly infected cultivar Inkeri [mean (standard deviation of mean) of 0·95 (0·023)]. Mean frequencies of infection of three cultivars remained lower than 0·10, and two of the cultivars, Kasper and Salten, were intermediately infected. In most of the cultivars, frequencies of infection varied only slightly among seed lots. In cultivar Kasper, however, the frequency of endophyte infection was highly variable (0–0·96) among the 45 seed lots examined. The relative importance of cultivar, seed lot and infection by Neotyphodium endophyte to the aphid Rhopalosiphum padi L. was studied experimentally, using both endophyte-free and endophyte-infected plants of four seed lots of the two intermediately infected cultivars. Endophyte infection increased plant resistance to R. padi , overriding the influences of seed lot and cultivar. It is proposed that variation caused by endophyte infections in cultivars of meadow fescue should be taken into account in assessing plant breeding programmes in Europe.     

Investigation of Polymorphisms in Coding Region of OsHKT1 in Relation to Salinity in Rice

Rice(Oryza sativa) is sensitive to salinity, but the salt tolerance level differs among cultivars, which might result from natural variations in the genes that are responsible for salt tolerance. High-affinity potassium transporter(HKTs) has been proven to be involved in salt tolerance in plants. Therefore, we screened for natural nucleotide polymorphism in the coding sequence of Os HKT1, which encodes the HKT protein in eight Vietnamese rice cultivars differing in salt tolerance level. In total, seven nucleotide substitutions in coding sequence of Os HKT1 were found, including two non-synonymous and five synonymous substitutions. Further analysis revealed that these two non-synonymous nucleotide substitutions(G50T and T1209A) caused changes in amino acids(Gly17Val and Asp403Glu) at signal peptide and the loop of the sixth transmembrane domain, respectively. To assess the potential effect of these substitutions on the protein function, the 3D structure of HKT protein variants was modelled by using PHYRE2 webserver. The results showed that no difference was observed when compared those predicted 3D structure of HKT protein variants with each other. In addition, the codon bias of synonymous substitutions cannot clearly show correlation with salt tolerance level. It might be interesting to further investigate the functional roles of detected non-synonymous substitutions as it might correlate to salt tolerance in rice.     

马铃薯试管苗组织培养及微型薯诱导技术的研究

通过加入不同浓度的BA、NAA和KT,以探讨外源激素对马铃薯试管苗生理性状的影响,发现低浓度的外源激素较适合用来进行试管苗的增殖。本试验利用香豆素进行微型薯的诱导,结果表明低浓度的香豆素对提高薯重和大薯率有利,而高浓度有利于提高微型薯的结薯数量。     

Role of invertase in the accumulation of sugars in cold-stored potatoes

Freshly harvested potatoes contain low levels of total invertase and high levels of invertase inhibitor. Total invertase increases sharply when potatoes are placed in cold storage, but the inhibitor is not depleted in all varieties. The absence of basal invertase activity in Norchip tubers indicates that an excess of invertase is not required for reducing sugar formation. Analyses of 37 varieties and seedlings after 3 months cold storage revealed that the reducing sugar content is not proportional to the invertase activity. High sugar contents are associated with low inhibitor levels, but low sugars are not necessarily associated with high inhibitor levels. The results indicate that invertase participates in reducing sugar formation, but other factors are responsible for the regulation of starch-sugar conversion in potatoes during cold storage.     

Quantitative assessment of metals in local brands of tea in Pakistan

In present study, Mn, Fe, Zn, Cu, Co, Pb, Cr, Ni and Cd were analyzed by FAAS in green and black tea samples of locally available in the Pakistani market. Na and K were also determined by Flame Photometer. Tea leaves can be the source of mineral components and trace elements, as well as some undesirable substances due to exposure to the environment. Among the metals tested, K was the most abundant one followed by Na, Mn and Fe. Fortunately, toxic heavy metals, Pb and Cd, had the lowest contents in tea samples and also in tea aqueous extracts. Concentration of heavy metals in tea aqueous extract was markedly lower than their total contents except that of K. The solubility of studied metals in tea aqueous extract varied widely and ranged from 0.0-95%. The lowest ranges of solubility were listed for toxic heavy metals Pb and Cd. The possible uptake of metals by the human body from tea aqueous extract has also been determined. The amounts of metals that one may take up through consumption of tea aqueous extract were found to match the acceptable daily intake even taking into account exposure from air, food and drinking water.     

玉米耐盐性研究进展

综述了玉米耐盐生理机制和耐盐育种的研究进展。     

用蛭石做马铃薯快繁培养基支持体的初步研究

1　前　言目前 ,马铃薯脱毒快繁技术已广泛应用于科研与生产中 ,快繁过程中脱毒苗培养基支持体通常采用琼脂或直接采用液体培养。然而这两种培养基存在着诸多问题 ,例如琼脂培养基中的琼脂价格昂贵、成本高 ,而且胶体不利于营养物质的扩散、透气性差 ,导致瓶苗生长不良。因此 ,该实验在本着降低成本的同时 ,又能保证瓶苗正常生长的前提下 ,以蛭石代替琼脂 ,分析其在实际生产中的应用价值。2　材料与方法2 1　材料供试品种为郑薯 6号脱毒苗 ,试验于 2 0 0 2年在郑州市蔬菜研究所马铃薯脱毒实验室内进行。2 2　方法本试验设两个处理 :处理 1…     

Matlab在玉米子粒灌浆特性分析中的应用

利用Matlab软件对玉米子粒灌浆过程用Richards方程进行拟合后,通过编程实现灌浆次级特征参数计算,并对不同播期子粒灌浆特征进行分析和探讨。结果表明,在黑龙港地区生态条件下,不同播期玉米各部位子粒灌浆均符合"S"形生长曲线,可用Richards方程很好地拟合。不同播期条件下,早播处理子粒起始势最高,达到灌浆盛期时间最早,平均灌浆速率及最大灌浆速率最大,活跃灌浆期较长,粒重最高。各播期玉米不同部位子粒,穗下部与上部相比,子粒的起始生长势较大,平均灌浆速率较高,达到灌浆高峰期时间较短,粒重较高。     

5个马铃薯品种组培幼苗的磷效率差异研究

试验以5个生产用马铃薯品种脱毒试管苗为材料,采用组织培养的方法,初步研究了茎切段在正常磷及低磷培养基中生长30 d时幼苗的磷营养效率差异,为筛选出适宜于生产用的磷高效马铃薯品种奠定了基础。试验结果表明,5个马铃薯品种幼苗在正常磷和低磷胁迫下对磷素的吸收和利用能力均存在明显的基因型差异。利用各品种幼苗的磷效率指标(植株干重、鲜重、吸磷量、磷利用效率)的相对指标(低磷处理的结果/正常磷处理的结果×100)进行聚类分析(类平均法)的结果表明,大白和I-1035属于磷高效基因型品种,中农Ⅷ是磷低效基因型品种,凉薯97和疫不加则属于中间类型品种。