新疆伊犁地区亚麻田杂草调查

采用倒置“W”9点取样法对新疆亚麻主栽区——伊犁地区亚麻田进行了杂草调查。结果表明伊犁地区亚麻田的杂草有15科26种，单子叶杂草狗尾草、稗草、野燕麦，双子叶杂草灰绿藜、卷茎蓼的相对多度在20以上，是亚麻田杂草的优势种群。     

二甲四氯钠与烯草酮混用对亚麻田杂草的防除效果

在新疆伊犁进行了二甲四氯钠与烯草酮混用防除亚麻田一年生阔叶杂草和禾本科杂草的田间试验,结果表明:药后30 d,二甲四氯钠与烯草酮混用对亚麻田杂草的株防效和鲜重防效均在88%以上,明显高于二者单用时的防效,且持效期长,一次施药能控制亚麻田生育期大多数杂草,对亚麻安全,两者混用是有效控制亚麻田杂草的理想措施。     

甘肃省亚麻田杂草种类及危害程度评价

为准确评价农田杂草的危害程度,为亚麻杂草综合防控提供依据,采用倒置"W"9点取样法调查甘肃省亚麻主产区亚麻田杂草种类、株数、株高和盖度.依据调查结果分析提出相对优势度RA的计算公式:RA=RD(相对密度)+RF(相对频度)+RU(相对均度)+RH(相对高度)+RC(相对盖度).该计算方法与国内外文献报道的不同,属于计算...     

亚麻化学除草技术应用研究

在调查出宾川县亚麻田杂草种类,分析出亚麻田杂草发生规律的基础上,研究出亚麻化学除草的药剂和配方以及相应的施用技术.3年累计示范推广亚麻化学除草5701.7hm2,节约生产费用846.5万元,新增总产值836.1万元,新增纯收益797.1万元,科技投资收益率120.44,经济效益非常显著.     

应用化学除草剂防除亚麻田杂草研究初报

亚麻是平播密植作物,杂草对它为害很大,一般亚麻田每平方米有杂草100—200株,不仅影响产量,而且收获后往往因麻把内夹有杂草而造成亚麻霉烂,降低品质。广大社员为提高亚麻产量和品质,增加收入,多在苗期进行1—2次人工拔草。     

亚麻专用除草剂在亚麻田上应用效果研究

为研究亚麻专用除草剂在亚麻田上应用效果,我们在黑龙江省四个种麻区开展了两年小区试验和一年大区对比试验。结果表明：在杂草2—5叶期,亚麻专用除草剂用药商品量1050ml/hm2,喷液量405㎏/hm2,苗后茎叶处理,可以完全控制亚麻田杂草危害。亚麻原茎和种子产量比不除草田分别增产28.41%和39.59%,增加工农业产值5865.35元/hm2;比常规药剂除草田分别增产9.16%和25.28%,增加工农业产值3000元/hm2左右,对亚麻安全,无药害。     

亚麻化学除草技术应用研究

在调查出宾川县亚麻田杂草种类，分析出亚麻田杂草发生规律的基础上，研究出亚麻化学除草的药剂和配方以及相应的施用技术。3年累计示范推广亚麻化学除草5701．7hm^2，节约生产费用846．5万元，新增总产值836．1万元，新增纯收益797．1万元，科技投资收益率1：20．44，经济效益非常显著。     

烯草酮防治亚麻田杂草药效试验

亚麻为平播密植作物,杂草发生较重,杂草防治效果直接影响亚麻的产、质量。2012年我们完成了24％烯草酮防治亚麻田禾本科杂草药效试验。田间试验结果表明：24％烯草酮乳油450-600ml／hm2。对禾本科杂苹有较好的防除效果,亚麻原茎、种子、纤维均比空白对照增产35．77％-45．76％、21．82％-28．20％、47．72％-50．65％;烯草酮对狗尾草、马唐、野黍、碱草等抗性杂草有特效,在一定范围内使用对亚麻安全。     

冀西北油用亚麻田杂草调查及化学防控技术研究

本文系统调查了冀西北地区油用亚麻田苗期杂草种类、群落及优势杂草,并开展了化学除草防除试验。结果表明,本区域油用亚麻田苗期杂草种类有16科43种,禾本科、菊科、藜科、蓼科,苋科为优势种,占杂草种类55.3%。优势杂草主要有藜、苦荞、狗尾草、野糜子、苋、野燕麦、苣荬菜、卷茎蓼、芦苇、皮碱草和野油菜11种。杂草群落类型为2~12元群落,以6~9元群落居多。试验筛选出防除阔叶杂草除草剂40%2·甲辛酰溴乳油等3种,防效在85%左右;防除禾本科杂草的除草剂10.8%高效盖草能等7种,防效在90%以上。筛选的所有除草剂对胡麻安全,可以在油用亚麻产区大面积推广应用。     

几种芽前除草剂对冬季亚麻田杂草的防除效果研究

为筛选对冬季亚麻苗期安全、高效、低成本的除草药剂,本研究比较了不同化学除草剂及其不同用量对亚麻田间杂草的防除效果,并以人工除草和不除草方法为对照,对比分析不同除草方法的投入和产出情况。结果表明,90%异丙甲草胺乳油2250 ml/hm2处理对冬季亚麻田杂草的防除效果较好,对亚麻生长安全,能显著降低劳动力和生产成本投入,提高亚麻种植效益,可以作为冬季亚麻田芽前化学除草方法推广应用。     

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.     

我国发展能源油料作物的策略分析

分析了国内外植物油脂的供需形势、我国耕地和边际地利用潜力、油脂植物资源的种属分布特点等,提出发展我国能源油料作物和生物柴油产业的3点建议：加大对边际地、油脂植物资源的调查等基础平台性研究,为政府决策和产业服务;加强产学研结合,形成研究、推广、产业的良性循环;制定能源植物推广应用优惠政策、推动能源油料作物生产发展。     

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。     

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.