不同降水年型下旱地深翻时间和施肥方式对小麦产量及水肥利用率的影响

为提高旱地小麦自然降水和肥料利用效果以实现稳产高产栽培,通过3个不同降水年型田间试验,研究了晋南旱地麦田休闲期深翻时间和氮、磷施用方式对小麦群体、产量及水肥利用率的影响。结果表明,休闲期降水量及其分布、深翻时间和施肥方式共同影响旱地小麦播前0~200 cm土壤蓄水量、产量、水肥利用效率。休闲期丰水年较平水年和枯水年分别增产75.29%和170.39%,播前0~200 cm土壤贮水量分别多42.77 mm 和116.91 mm,水分利用效率分别高2.94和8.77 kg·mm^-1·hm^-2,氮、磷利用效率也较高。8月中上旬深翻蓄水效果较好,可促进小麦植株和籽粒对氮、磷的吸收,增加冬前茎数和穗数,8月中旬深翻较7月中旬深翻增产5.43%~18.15%,播前0~200 cm土壤贮水量增加12.12~18.45 mm,水分利用效率和磷素利用率也较高。与播种前配施氮、磷肥相比,8月中上旬深翻时配施磷肥,播种前施入氮肥,可提高冬前和拔节期茎数、穗数和穗粒数,促进氮、磷积累和转运,从而增产,同时提高收获期0~200 cm土壤贮水量和水分利用率。在当前气候、栽培条件下,晋南丘陵旱地不同降水年型下均以8月中上旬深翻配施磷肥,播种前施入氮肥可提高土壤渗水特性,最大限度纳秋雨蓄墒,增加小麦冬前和拔节期茎数和穗数,提高产量和水肥利用效率。     

枯草芽孢杆菌对植烟土壤养分含量与酶活性的影响

为探讨枯草芽孢杆菌微生物菌剂对土壤主要养分含量及酶活性的影响,以及施用枯草芽孢杆菌后的土壤养分与酶活性间的关联性,以K326为材料,开展了枯草芽孢杆菌微生物菌剂不同用量研究。结果表明:烤烟移栽以后,(1)土壤有机质含量呈现下降趋势;碱解氮和有效磷、钾含量则呈现"低-高-低"的变化规律,且烤烟移栽后45 d达到最大值;(2)土壤脲酶活性呈现由低到高的变化,移栽后90 d达到最大值;过氧化氢酶活性呈现"低-高(60 d)-低-较高(90 d)"的规律性变化;蔗糖酶活性出现"较高-低(60 d)-高(75 d)-高(90 d)"的规律性变化;(3)通过土壤酶活性对土壤有机质、碱解氮和速效磷、钾含量间的灰色关联分析表明,土壤脲酶活性在移栽后45 d对有机质和碱解氮,以及移栽后60 d对速效磷和钾含量影响最大;过氧化氢酶和蔗糖酶活性,分别在移栽后60 d和75 d,对土壤有机质、碱解氮,及速效磷和钾的含量影响最大。植烟土壤施用枯草芽孢杆菌,对提高土壤养分含量及酶活性有着良好的效果,不同生长阶段土壤养分与酶间相互作用有差异。     

不同有机肥与无机肥配施对小麦产量、效益及土壤养分的影响

为探讨不同品牌有机肥与无机肥配施对小麦产量、效益及土壤养分的影响,选用蕾特、名远、绿盈、邦禾4种品牌的有机肥开展研究。结果表明,有机肥与无机肥配施能够提高小麦产量,4种有机肥比常规施肥平均增产4.9%,其中增产效果最佳的是蕾特有机肥,比常规施肥增产9.1%,达极显著水平,穗粒结构上主要表现在增粒增重。在效益上,除蕾特有机肥比常规施肥增效1.8%外,其余3种有机肥当季效益均不明显。有机肥与无机肥配施对土壤养分含量影响较为明显,4种有机肥施用后土壤有机质、全氮、有效磷、速效钾含量分别增加2.2 g/kg、0.16 g/kg、0.8 mg/kg、2.8 mg/kg。4种有机肥中,蕾特有机肥在产量、效益及土壤养分含量变化上的表现优于其余3种产品,可在本地区示范推广。     

不同茬口对小麦养分利用和产量的影响

为了探究不同茬口对小麦生产的影响,在测定玉米、大豆、花生、甘薯4种不同作物收获后土壤养分状况的基础上,对不同茬口下小麦植株养分吸收、利用和产量进行了研究。结果表明,与玉米茬相比,大豆茬的土壤速效磷含量降低,土壤速效氮和速效钾含量提高,花生茬的土壤速效氮和速效磷含量提高,甘薯茬的土壤速效氮和速效钾含量下降;大豆、花生和甘薯茬有利于小麦植株养分的积累,并能显著提高千粒重,但甘薯茬的小麦产量显著低于玉米茬。因此,大豆和花生可作为冬小麦种植区两熟复种模式的适宜前茬作物。     

沟播集中施肥对旱地小麦产量及产量因素的影响

小麦沟播集中施肥较平播撒施肥料对提高肥料利用率和改善农田生态条件等有明显的作用.有利于提高播种质量和培育壮苗。这种施肥方法对小麦生长发育的主要影响,表现为根系发达活力强,叶面积大.有效分蘗多.穗、粒重协调发展.具有穗多、粒多的优势.产量显著高于平播撒施肥。产量构成的三因素的增产效应依次为公顷穗数>穗粒数>千粒重。     

土壤调理剂在酸化稻田连作晚稻上的应用效果

为了探明土壤调理剂对酸化稻田土壤理化性状及连作晚稻产量的影响效应,挖掘甬优538高产潜力,设置了土壤调理剂32%氨基质钙镁肥不同用量试验。结果表明,施用土壤调理剂对甬优538有明显增产效应,其中每hm2施600 kg、900 kg、1 125 kg的处理比未施用对照增产8.31%~9.52%,达显著水平;其增产效应主要在于增加有效穗数和提高千粒重;施用土壤调理剂还能有效改善酸化稻田土壤理化性状,促进碱解氮、有效磷及速效钾的释放利用和有机质提升。通过一系列数学关系模型分析后发现,在生产上土壤调理剂施用量以600~900 kg/hm2为宜。     

微生物肥对小麦产量、赤霉病以及土壤养分的影响

为探讨微生物肥对小麦产量的影响、对赤霉病的防控作用以及对土壤理化性状的改良作用,以扬麦20为供试材料,进行"金菌冠"微生物肥不同用量(0、600、900、1200、1500、1800 kg/hm2)的配合处理试验.结果显示:施用微生物肥可以显著增加冬小麦的产量,施用量为1500 kg/hm2时,小麦产量最高,增产达10.37％;对赤霉病也有一定的防治效果,防效可达52.54％.与常规施肥相比,增施该肥后土壤有机质含量(质量分数,下同)提高1.44％～9.80％,碱解氮含量提高4.42％～13.42％,有效磷含量提高5.33％～28.40％,速效钾含量提高4.79％～21.92％,pH值降低2.94％～5.70％.     

富磷有机肥对北疆棉花产量和土壤理化性质的影响

以不施富磷有机肥为对照,以富磷有机肥施用量900 kg·hm^－2、1 800 kg·hm^－2和2 700 kg·hm^－2为处理,研究富磷有机肥施用对北疆棉花出苗率、产量和土壤理化性质的影响。结果表明：（1）富磷有机肥施肥水平对北疆棉花出苗率无显著影响。（2）900 kg·hm^－2的富磷有机肥处理对棉花增产最为显著,其余2个处理对棉花产量无显著影响;富磷有机肥处理间棉花产量差异不显著。（3）富磷有机肥不同施肥水平对不同土层（0～20 cm、20～40 cm）土壤速效氮磷钾与有机质含量、pH和土壤总盐含量均无显著影响。     

华北平原两熟区不同夏播作物对土壤养分和小麦籽粒产量及品质的影响

两熟种植模式一直是华北平原的主要种植模式，冬季作物以小麦为主，夏季则以玉米、大豆、棉花和薯类等作物为主。为研究不同夏播前茬作物对后茬小麦产量和品质的影响，选用玉米（T1）、大豆（T2）、花生（T3）和甘薯（T4）四种夏播作物，在播种前和收获后检测田间土壤养分变化，以及后茬小麦的籽粒产量和品质。结果表明,大豆收获后，15～30 cm土层土壤碱解氮和速效磷含量分别提高129.75%和43.93%，远高于其他前茬处理；花生收获后，15～30 cm土层土壤碱解氮和速效磷含量与播前相比基本保持平衡；四种前茬处理下土壤速效钾和有机质含量均显著增加。玉米前茬和花生前茬处理下，小麦产量和籽粒中氮、磷、钾的积累量显著高于大豆前茬和甘薯前茬处理，小麦产量比甘薯前茬处理分别提高38.15%和31.13%。花生前茬能够有效提高后茬小麦籽粒干基蛋白、湿面筋含量和籽粒容重，大豆前茬能够提高后茬小麦籽粒的干基淀粉含量，甘薯前茬能够提高后茬小麦的出粉率。总的来看，选择花生做前茬，在保持后茬小麦产量较高的同时，能够提高小麦籽粒的品质性状。     

麦秆全量还田对水稻农艺性状、产量及土壤性状的影响

通过3 a麦秆全量还田,研究其对水稻农艺性状及产量形成、土壤性状的影响。结果表明,与不还田处理相比,麦秆全量还田抑制了前期水稻个体和群体生长发育,在栽后30～35 d内总茎蘖数减少,到达高峰苗时间推迟1个叶龄期,每667 m2高峰苗数少2.15万,但成穗率提高9.0%;每667 m2有效穗数增加7.62%,每穗粒数增加9.14%,结实率降低4.01%,千粒重降低0.5%,产量增加11.4%;麦秆全量还田使土壤pH值下降,土壤有机质提高9.4%、碱解氮提高4.5%、速效磷提高16.7%、速效钾提高16.9%。     

Analysis of nutritional components of eight famine foods of the Republic of Niger

In the western Sahel, indigenous plants become important staples when cereal harvests are inadequate to support populations inhabiting that region of Africa. The purpose of this study was to assess the nutrient content of several of these edible wild plants. The leaves of the following seven plant foods were analyzed: Ziziphus mauritiana, Cerathotheca sesamoides, Moringa oleifera, Leptadenia hastata, Hibiscus sabdarifa, Amaranthus viridi, and Adansonia digitata. The fatty acid, vitamin E, carotenoid, selected mineral and amino acid contents of these plant foods were determined. These same analyses were performed on the fruit of the Adansonia digitata. In quantitative and qualitative terms, Amaranthus viridis was found to be an excellent source of protein. Its amino acid composition compared favorably to that of a World Health Organization (WHO) protein standard. It also contained considerable amounts of the two fatty acids that are essential in humans (linoleic and -linolenic) and a number of minerals including iron, magnesium, calcium and zinc. The leaves of Hibiscus sabdarifa contained an appreciable quantity of protein the composition of which was comparable to the WHO standard. The mineral content of the leaves of this plant was also exceptionally high; noteworthy was its high zinc content. H. sabdarifa also contained significant quantities of the two essential fatty acids. Ziziphus mauritiana was an excellent source of the essential fatty acid linoleic acid and several of the metals including iron, calcium, magnesium and zinc. Its content of other essential nutrients, however, was rather low. In general, Adansonia digitata leaves were nutritionally superior to the fruit of the tree; however, the fruit did contain useful quantities of potassium, phosphorus, zinc and -linolenic acid. The Leptadenia hastata leaves were an especially good source of lutein and -carotene. These data should be useful to the people who inhabit the western Sahel in helping them devise healthy diets during times when cereal staples are in short supply.     

芦笋枯萎病病原鉴定

对造成福建省漳州市东山县的芦笋枯萎病病原菌进行分子鉴定,以期确定病原菌的属、种名,为防治该病害寻求理论依据。试验对分离纯化的病原菌核糖体DNA的ITS区进行测序,在Genbank中搜索其同源性并构建它们的系统发育树,结果表明：引起芦笋枯萎病的病原菌是镰刀属中的尖孢镰刀菌(Fusarium oxysporum),且病原菌之间的同源性高达89%,遗传差异不显著。     

狗牙根诱变后代抗寒性评价

通过电解质外渗法和匍匐茎恢复试验对‘阳江’狗牙根及其12个通过形态鉴定选出的坪用价值高且花序密度低的诱变后代进行抗寒性鉴定。电解质外渗法结果表明:诱变后代间的抗寒性具有较大差异,其叶片半致死温度(LT₅₀)的变异范围为-7.6～-0.2℃(最低值与最大值相差7.4℃);参试材料抗寒性由强到弱依次为M18>M4>M26>M28> M22>阳江>M29>M31>M10>M37>M16>M1>M25,其中,有5个诱变后代抗寒性优于亲本,分别是M18、M4、M26、M28、M22。匍匐茎恢复实验结果表明:诱变后代M1、M22、M26、M31、M25在0℃和-5℃低温胁迫后的恢复生长率都高于亲本,恢复能力均优于亲本;M10、M37、M28在-5℃低温胁迫下,恢复生长能力低于亲本,抗寒性相对较弱,M16和M4在0℃和-5℃低温胁迫下,恢复生长率都低于亲本,抗寒性明显弱于亲本。综合2种方法鉴定结果显示:诱变后代M1、M25的恢复能力较强;M4、M28的叶片抗寒性较好,青绿期较长;M22、M18、M26的叶片抗寒性和匍匐茎恢复能力均较强;M29,M31的叶片抗寒性和匍匐茎恢复能力与亲本相似;M10、M16、M37的叶片抗寒性和匍匐茎恢复能力均较弱,整体抗寒性较弱。     

玉米产量性状配合力遗传分析

通过对8个中晚熟玉米自交系产量性状进行双列杂交分析，表明各个自交系产量性状的一般配合力与特殊配合力存在显著差异，玉米杂交种F₁的产量构成受到一般配合力与特殊配合力的共同作用，用特殊配合力对F₁的作用大于一般配合力。特殊配合力高低与一般配合力无明显相关关系。因此在玉米杂交种组配与自交系改良工作中，既要兼顾双亲的一般配合力与特殊配合力，又要保持杂交优势利用模式与选系模式的种质关系。     

Mechanism of action of insecticidal secondary metabolites of plant origin

Insect pest management is facing the economic and ecological challenge worldwide due to the human and environmental hazards caused by majority of the synthetic pesticide chemicals. Identification of novel effective insecticidal compounds is essential to combat increasing resistance rates. Botanicals containing active insecticidal phytochemicals appear to be promising to address some of these problems. Therefore, there is a continuous need to explore new active molecules with different mechanisms of action. Secondary metabolites present in plants apparently function as defense (toxic), which inhibits reproduction and other processes. The phytochemical biomolecules could be used for maximizing the effectiveness and specificity in future insecticide design with specific or multiple target sites, while ensuring the economic and ecological sustainability. In this article, the current state of knowledge on phytochemical sources and insecticidal activity, their mechanism of action in insects, resistance, and promising advances made in phytochemical research are reviewed.     

马铃薯黑痣病菌生物学特性测定

马铃薯黑痣病是土传真菌性病害,在定西市马铃薯种植区均有发生,目前已成为影响马铃薯产量和品质的主要因素之一。本研究对马铃薯黑痣病菌从温度、光照、碳源、氮源以及p H方面进行了生物学特性的测定。结果表明:该病原菌菌丝在无光25℃条件下生长最快,在无光35℃条件下生长最慢;室温条件下培养1 d后用紫外线照射处理2 h,然后室温持续光照培养4 d的菌丝生长速率最大,持续黑暗培养4 d的菌丝生长速率最慢;不同碳氮源对该菌菌丝生长均有影响,碳源为淀粉的培养基上菌丝生长最快、氮源为尿素的培养基上菌丝生长最快;培养基p H中性时菌丝生长速率最大。     

橡胶树丛枝病病原的抗血清制备与应用

以感染橡胶树丛枝病病原的长春花为材料,制备得到橡胶丛枝病病原菌抽提液,以抽提液为抗原免疫家兔,制备抗血清,经微量沉淀测定,抗血清效价为１：２０４８。应用橡胶丛枝病抗血清检测橡胶褐皮病,无症苗木检出率达３０％－３７％,可疑的褐皮病树检出率达８５．７％。     

Valorization of three varieties of grape

In the present investigation, seed methanolic extracts of three Vitis vinifera (Muscat d’Italie, Syrah and Carignan) were assayed for their antioxidant activities. Results showed that there are strong variations in the contents of total phenols (440.97–121.94 mg GAE g⁻¹ DW), flavonoids (48.07–16.81 mg EC g⁻¹ DW) and tanins (37.15–14.9 mg EC g⁻¹ DW) from the studied seeds. The phenolic composition of these extracts was determined by RP–HPLC after acid hydrolysis. The main phenolic compound was quercetin with 27.2% in Muscat d’Italie, 48.8% in Syrah and 28.4% in Carignan. Besides, all seed extracts showed remarkable DPPH radical scavenging activity with IC₅₀ values ranged from 1.8 to 30 μg ml⁻¹. EC₅₀ values of reducing power activity ranged from 100 to 120 μg ml⁻¹. The high phenolic content and the considerable antioxidant activities of vitis seed extracts could potentially be considered as an expensive source of natural antioxidants.     

Size and frequency of occurrence of pre-roost gatherings of starlings

One hundred and fifty-six pre-roost gatherings of starlings were observed at 28 sites around a roost in west Norfolk during winter. Pre-roost gatherings occurred more frequently at individual farmyards compared with individual fields, but 82% of the sites where gatherings occurred were on fields. The size of gatherings was greater, the closer to the roost. Birds in pre-roost gatherings on fields of autumn-sown winter wheat spent most of the time feeding and had a diet composed almost exclusively of wheat seeds. Birds in gatherings on grass fields also fed intensively whereas only 31% of birds at farmyards were feeding. The implications that these results have with regard to potential damage to fields of winter wheat and around farmyards are discussed.     

几个粳稻不育系、恢复系产量性状配合力研究

新粳型不育系和恢复系是通过籼粳交或粳粳交的方式培育而成的中间型稳定品系,杂交组合的育性正常或接近正常。粳型不育系和恢复系配组,杂种F1的产量性状差异显著或极显著。组合9512A/R364、73A/R55、150A/R198、9512A/R2690、150A/R55,具有产量的正向超亲、超标优势,另一些组合呈显著或极显著的负向优势;本研究产量性状一般配合力好的不育系是中14A、辽150A、73A、9512A、9214A,恢复系是R198-2、R238、R46、C418、R364和花38;亲本的产量性状一般配合力和特殊配合力在不同性状的作用没有交叉。杂种优势的表现与双亲亲和力高低、配合力高低有明显的相关性。辽150A、9512A的超亲优势明显,R198、R55、R2690、R364、C204等恢复系具有较强的杂交优势。不育系对产量性状的作用显著大于恢复系。