棉花花铃期的管理措施

花铃期是棉花营养生长与生殖生长并盛期 ,既要保证营养器官有一定的长势 ,又要满足生殖器官的养分供应 ,争取多结桃、少脱落 ,是此阶段田间管理的要点。1重施花铃肥花铃期是棉花一生中需肥量最大的时期 ,约占需氮总量的 60 %。可在初花期施标准氮肥 1 5 0～2 2 5 kg·hm-2 ,至开花结铃期再施 2 2 5 kg。对长势较弱的棉田 ,还应补施盖顶肥 ,一般施标准氮肥 75～ 1 5 0 kg。对土壤速效磷含量不足 1 0 g· kg-1的棉田 ,于开花结铃期喷施 1 %～ 2 %的过磷酸钙浸出液 ,或 30 0～ 5 0 0倍的磷酸二氢钾溶液 ,对保蕾保铃有较好的效果。生育后期易发…     

棉花增施健桥牌有机肥对其产量和效益的影响

为了检验江苏省南通市金桥生物肥料有限公司生产的健桥牌有机肥在棉花上的效果.2012年和2013年连续两年通过应用配方化肥与该有机肥不同用量配施作棉花的基肥试验,比较棉花产量和效益.结果显示,在施配方氮磷钾化肥折N、P2 O5、K2O用量分别为281.25、72.00、126.00kg/hm2下,再增施健桥牌有机肥9000～10000 kg/hm2获得的棉花产量和效益最佳,增施有机肥有利于增加现蕾和结铃.     

海涂棉花施肥量、化控量和群体大小三因素最优回归分析

浙江省近年来在海涂棉区推广棉花“矮、密、早、调”栽培模式,为了筛选群体大小与施肥量等的最佳组3合,以便达到节工省本高产稳产的目的。 在1997年密变、氮肥用量、助壮素用量三因素旋转回归试验的基础上,1998年进行了总果枝数、三要素用量和助壮素用量三因素最优回归试验。选得的最佳组合为施肥量是纯 N165～180kg·hm-2,P2O582．5～90kg·hm-2．K2O165～180kg·hm-2为宜;25%助壮素用量180m1·hm-2左右;单株留果枝9个,每公顷总果枝81万。     

宁夏引黄灌区春小麦施肥现状与评价

为了解宁夏引黄灌区春小麦养分资源管理中存在的问题,于2011-2013年采用农户抽样调查方法,分析评价了该灌区5个县市328个种植户的春小麦施肥和产量情况。结果表明,春小麦平均产量的年际间变幅不大,3年平均产量为4 578kg·hm-2。春小麦产量偏低的农户比例最高,3年平均达46.7%,产量适中的农户平均占23.7%,处于适中以下的农户比例在50%以上。3年春小麦的纯N、P2O5、K2O平均用量分别为357.0、182.7、33.4kg·hm-2。平均86.4%的春小麦种植户氮肥投入过量,44.6%的磷肥施用过量,83.3%的钾肥投入严重不足,肥料养分投入与产量水平分布并不同步。养分投入以化肥为主,有机肥为辅;重氮肥,轻钾肥。化肥N、P2O5、K2O用量分别占养分总投入量的96.6%、98.0%和79.0%。氮肥运筹以基肥和追肥为主,基追比大致为6∶4;磷肥以基肥和种肥为主,钾肥几乎全部通过基肥施入。春小麦每投入1kg纯N、P2O5、K2O养分,平均分别可生产14.8、30.0和154.7kg籽粒,肥料生产力总体趋势为K2OP2O5N。因此,建议宁夏引黄灌区春小麦采用有机无机肥料配施、氮肥后移(60%追肥)的原则,并注意减氮、控磷、补钾,有机肥以30t·hm-2为宜,化肥N、P2O5、K2O投入分别不超过225、180、60kg·hm-2。     

模糊数学在棉花有机肥分期配施评判中的应用

以 1 998 - 1 999年有机肥分期配施创棉花2 2 5 0 kg· hm-2 高产试验为例 ,应用模糊概率法 ,综合评判了铃数、铃重、衣分、子指、衣指及子棉经济系数等 6个产量性状对棉花成铃时空分布的影响 ,明确了有机肥分别作基肥和花铃肥平均施用为创棉花高产的最佳施肥方式     

棉花施用钾肥的增产效应研究

钾素是棉花需求的三大营养元素之一。一直认为碳酸盐石灰性土壤缺氮少磷富钾。但随着长期施用氮肥、增施磷肥 ,钾肥已成为限制棉花产量提高的主要因素之一。1材料和方法1 .1试验设计。试验于 1 998～ 2 0 0 1年在山西省永济市卿头镇、蒲州镇、开张镇、栲栳镇进行。在每公顷普施氮肥 ( N) 1 5 0 kg、磷肥 ( P2 O) 1 5 0 kg基础上 ,设置钾肥 ( K2 O kg· hm-2 )试验处理为 :1 0 .0 0 (对照 ) ;2 37.5 ;375 .0 ;41 1 2 .5 ;5 1 5 0 .0。钾肥和磷肥作基肥一次施入 ,氮肥三分之一作基肥 ,三分之二追施。试验小区面积 0 .75 hm2 ,重复三次 ,随机…     

氮肥运筹模式对冬小麦氮素吸收利用的影响

为给小麦高产、高效、无污染及可持续生产提供合理的氮肥运筹技术和理论依据, 以烟农19为材料,在大田条件下,研究了不同施氮量和基追比例对土壤小麦系统氮素积累及分配的影响。结果表明,施氮可提高0~100 cm土体内的全氮含量。在小麦越冬前, 0~40 cm土层中NO3-N含量随氮肥用量和基肥比例的增加显著增加;起身期到拔节期,施氮量为180和240 kg·hm-2且基肥∶拔节肥∶孕穗肥为3∶5∶2处理的0~40 cm土层内NO3-N含量下降,而施氮量为240 kg·hm-2且基肥∶拔节肥为7∶3和5∶5的处理及施氮量为300 kg·hm-2且基肥∶拔节肥为7∶3的处理则显著增加;拔节期到成熟期,随施氮量的增加,0~60 cm土层速效氮增加幅度有所提高。孕穗肥可明显提高灌浆期的植株全氮含量。因此,在240 kg·hm-2 施氮水平、基肥∶拔节肥∶孕穗肥为3∶5∶2条件下,施氮既能减少土壤硝态氮累积量,又能有效降低土壤硝态氮污染地下水的可能性。     

栗钙土施肥土壤有机碳特性与平衡调控研究

有机无机肥配施明显改善了栗钙土土壤有机 C特性 ,土壤总有机 C、易氧化 C、重组 C、有机 C复合量增大 ,提高了土壤有机 C活性 ,松、稳和紧结态 C含量增加 ,且以紧、松结态 C为主 ,同砂质栗钙土相比 ,壤质草甸栗钙土呈现紧结态 C向稳结态 C转化趋势。不同有机物料在砂质栗钙土和壤质草甸栗钙土上腐殖化系数分别变化于 0 .2 5～ 0 .68和 0 .4 1～ 0 .72之间 ,矿化率则分别变化于 2 .86%～ 4 .53%和 1 .1 0 %～ 3.77%之间。维持高水平土壤有机 C平衡的有机物料临界施用量砂质栗钙土需秸秆类肥 1 1 2 56.5kg· hm-2或畜粪肥1 0 953.4 kg·hm-2或农家肥 32 1 76.5kg· hm-2 ,而壤质草甸栗钙土则需秸秆类肥 7379.2 kg· hm-2或畜粪肥681 4 .0 kg·hm-2或农家肥 1 4 1 58.1 kg· hm-2。     

高海拔地区马铃薯高产中的钾肥效应研究

在贵州高海拔地区织金县采用马铃薯高产栽培技术和平衡施肥技术 ,马铃薯产量为14 91t/hm2 ,超过当地平均产量 1 5倍 ,钾肥配施可增产马铃薯 1 0～ 2 5t/hm2 ,增幅 8 0 6 %～2 0 6 3% ,施钾产投比可达 2 0～ 3 5。施钾肥后马铃薯薯块重量增加 19 2 % ,增产以增加薯块为主 ,马铃薯品质有较大改善 ,试验认为 ,高产高效施肥的N∶K2 O比为 10 0∶95～ 14 0为宜 ,即施氮 (N)10 5kg/hm2 ,施钾 (K2 O) 10 0～ 15 0kg/hm2 为宜。施磷量应根据土壤中缺肥情况进行调整。     

湖北省油菜施肥现状调查

对湖北省20个油菜主产县(市)的356个农户2007/2008年度油菜施肥状况进行了调查。结果显示,所有种植油菜的田块均施用了化肥;施用有机肥的比例仅为19.8%。全省油菜氮(N)、磷(P2O5)和钾(K2O)肥平均施用量分别为171.9、61.7和50.3kg.hm-2,N∶P2O5∶K2O的比例为1∶0.36∶0.29,其中化肥提供的N、P2O5和K2O分别占总投肥量的96.1%、92.1%和80.3%。施肥量分级结果表明,农户普遍重视氮肥的施用,施氮(N)量120 kg.hm-2的田块比例为64.3%;磷、钾肥施用不足,施磷(P2O5)、钾(K2O)量45kg.hm-2的比例分别为35.4%和48.9%。油菜施肥次数以两次(基肥+1次追肥)的比例最高,占56.0%;78.3%的氮肥用作基肥施用。调查结果表明,湖北省油菜种植中的施肥问题主要有:(1)养分不平衡,磷、钾肥用量偏低,尤其钾肥用量明显不足;(2)有机肥施用比例、施用量偏低,秸秆还田率低;(3)氮肥用量不足及过量的现象均有存在;(4)施肥次数与油菜生长及养分吸收规律不匹配,前期氮肥用量比例过高。     

Mineral composition of some traditional Mexican teas

Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described.     

Studies on natural repellents against potato tuber moth (Phthorimaea operculella Zeller) in country stores

Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.     

Comparative Assessment of the Efficacy of Various Nitrogen Fertilizers

Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.     

Redox Status and Neuro Inflammation Indexes in Cerebellum and Motor Cortex of Wistar Rats Supplemented with Natural Sources of Omega-3 Fatty Acids and Astaxanthin: Fish Oil,Krill Oil,and Algal Biomass

Health authorities worldwide have consistently recommended the regular consumption of marine fishes and seafood to preserve memory, sustain cognitive functions, and prevent neurodegenerative processes in humans. Shrimp, crabs, lobster, and salmon are of particular interest in the human diet due to their substantial provision of omega-3 fatty acids (n-3/PUFAs) and the antioxidant carotenoid astaxanthin (ASTA). However, the optimal ratio between these nutraceuticals in natural sources is apparently the key factor for maximum protection against most neuro-motor disorders. Therefore, we aimed here to investigate the effects of a long-term supplementation with (n-3)/PUFAs-rich fish oil, ASTA-rich algal biomass, the combination of them, or krill oil (a natural combination of both nutrients) on baseline redox balance and neuro-inflammation indexes in cerebellum and motor cortex of Wistar rats. Significant changes in redox metabolism were only observed upon ASTA supplementation, which reinforce its antioxidant properties with a putative mitochondrial-centered action in rat brain. Krill oil imposed mild astrocyte activation in motor cortex of Wistar rats, although no redox or inflammatory index was concomitantly altered. In summary, there is no experimental evidence that krill oil, fish oil, oralgal biomass (minor variation), drastically change the baseline oxidative conditions or the neuro-inflammatory scenario in neuromotor-associated rat brain regions.     

Potential of dry fractionation of wheat bran for the development of food ingredients,part II: Electrostatic separation of particles

Wheat bran is a composite material made of several layers, such as pericarp, testa and aleurone. It could be fractionated into purified fractions, which might either be used as food ingredients, or serve as a starting material for extraction of bioactive compounds. The aim of this work was to evaluate the potential of using electrostatic separation as a way to obtain purified fractions from wheat bran. Ultrafine-ground bran obtained either by cryogenic grinding or by grinding at ambient temperature was used as starting material. The ultrafine bran was then charged by tribo-electrification and introduced in a chamber containing two high voltage electrodes, where bran particles were separated depending on their acquired charge, allowing positively and negatively charged fractions to be collected separately. The particle size distribution, microstructure and biochemical composition of the obtained fractions were studied. The charge of the particles was influenced by their biochemical composition: particles rich in highly branched and cross-linked arabinoxylans (pericarp) were separated from particles rich in β-glucan, ferulic acid and para-coumaric acid (aleurone cell walls). The testa and the intracellular compounds from aleurone were not highly charged, neither positively nor negatively. The most positively charged fraction represented 34% of the initial bran, and contained 62% of the ferulic acid present in the initial bran. The yield of the separation process was good (5.4% loss), and could be further increased.     

Pharmacokinetics of Marine-Derived Drugs

Marine organisms represent an excellent source of innovative compounds that have the potential for the development of new drugs. The pharmacokinetics of marine drugs has attracted increasing interest in recent decades due to its effective and potential contribution to the selection of rational dosage recommendations and the optimal use of the therapeutic arsenal. In general, pharmacokinetics studies how drugs change after administration via the processes of absorption, distribution, metabolism, and excretion (ADME). This review provides a summary of the pharmacokinetics studies of marine-derived active compounds, with a particular focus on their ADME. The pharmacokinetics of compounds derived from algae, crustaceans, sea cucumber, fungus, sea urchins, sponges, mollusks, tunicate, and bryozoan is discussed, and the pharmacokinetics data in human experiments are analyzed. In-depth characterization using pharmacokinetics is useful for obtaining information for understanding the molecular basis of pharmacological activity, for correct doses and treatment schemes selection, and for more effective drug application. Thus, an increase in pharmacokinetic research on marine-derived compounds is expected in the near future.     

In vitro antimicrobial activity of different accessions ofSolanum commersonii Dun. from Uruguay

Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.     

La pourriture fongique des tubercules de pomme de terre en atmosphère contrôlée

Résumé Fusarium culmorum et, dans une moindre mesure,F. avenaceum, F. sambucinum, Colletotrichum coccodes etCylindrocarpon sp. ont été isolés de tubercules entreposés en atmosphère contr?lée (AC) et atteints de pourriture grave. Des expériences d'inoculation de tubercules avec 10 espèces ou variétés fongiques et conservation en AC à 8 et 10°C ont montré que: 1) les champignons non pathogènes en atmosphère normale (ex.:Cylindrocarpon sp.) le devenaient en AC, 2) ceux qui étaient faiblement pathogènes en atmosphère normale étaient nettement plus virulents en AC (ex.:F. culmorum), 3) les espèces ou variétés virulentes en conditions d'air normales (Fusarium sulphureum etPhoma exigua var.foveata) ne provoquaient pas de pourriture plus grave en AC et leur activité pouvait même être légérement freinée.

---

Summary The extensive rotting of tubers which occurred during storage trials in controlled atmospheres has led to a mycological and pathological study of the rots. The most frequently isolated species wasFusarium culmorum althoughF. avenaceum, F. Sambucinum, Coletotrichum coccodes and aCylindrocarpon sp. were also present. Tubers of cvs Bintje and Ulla were inoculated with 19 isolates of 10 fungal species or varieties associated with rotting of stored tubers (Table 1). The tubers were incubated at 8 or 10°C in normal or controlled (2% O₂:1% CO₂, 2% O₂:6% CO₂, 2% O₂:12% CO₂, 6% O₂:6% CO₂) atmospheres and the extent of rotting was determined a month later (Tables 2 and 3 and Fig. 2). Species which were weakly virulent in a normal atmosphere (variousFusarium spp. andPhoma exigua var.exigua) were clearly more aggressive in the controlled atmosphere and this was especially evident in the case ofF. culmorum. Species ot pathogenic in a normal atmosphere under experimental conditions (Colletotrichum coccodes, Cylindrocarpon sp.,Phoma eupyrena) caused rotting in the controlled atmosphere. The two species which were virulent in a normal atmosphere (F. sulphureum andP. exigua var.foveata) were also virulent in the controlled atmosphere and in some cases the extent of rotting was even less. As a general rule, rotting caused by weakly virulent fungi was greater in both cultivars in the controlled than in a normal atmosphere.

---

Zusammenfassung Eine starke F?ulnis von in Kontrotrollierter Atmosph?re gelagerten Kartoffelknollen veranlasste eine mykologische und pathologische Untersuchung. Der am h?ufigsten isolierte Pilz warFusarium culmorum. F. avenaceum, F. sambucinum, Colletotrichum coccodes undCylindrocarpon sp. wurden ebenfalls bestimmt. Neunzehn St?mme von 10 Pilzsorten oder-Arten welche bei Lagerf?ulnis vorkommen (Tab. 1) wurden auf Knollen der Sorten Bintje und Ulla inokuliert. Die Lagerung wurde bei 8 oder 10°C under Normalbedingungen oder kontrollierter Atmosph?re durchgeführt (2% O₂:1% CO₂, 2% O₂:6% CO₂, 2% O₂:12% CO₂, 6% O₂:6% CO₂). Der F?ulnisgrad (Abb. 1) wurde nach einem Monat bonitiert. Die Ergebnisse sind in den Tabellen 2 und 3 dargestellt und in der Abb. 2 illustriert. Unter in Normalbedingungen nur schwach virulente Arten (verschiedeneFusarien undPhoma exigua var. exigua) waren deutlich aktiver in kontrollierter Atmosph?re. Dies was besonders der Fall fürF. culmorum. Pilze, die im Versuch unter Normalbedingungen nicht pathogen waren (Colletotrichum coccodes, Cylindrocarpon sp., Phoma eupyrena), haben unter kontrollierter Atmosph?re Sch?den verursacht. Hingegen werden die beiden unter Normalbedingungen sehr pathogenen Arten (F. sulphureum undP., exigua var.foveata), durch kontrollierte Atmosph?re wenig beeinflusst. Es wurde sogar in einigen F?llen eine gewisse Verringerung des F?ulnisbefalls beobachtet. Ganz allgemein haben die getesteten kontrollierten Bedingungen die Entwicklung der Pilzf?ulnis an beiden Kartoffelsorten gef?rdert, speziell durch Pilzarten, welche unter Normal-bedingungen wenig Sch?den verursachen.