机插双季稻育秧适宜播种量研究

为确定双季稻机插育秧适宜播种量,以早稻品种淦鑫202、晚稻品种五丰优T025为材料,通过秧盘育秧试验和大田机插试验,研究了播种量对双季稻机插秧苗素质、机插质量及产量的影响。结果表明,播种量对秧苗素质、漏插率及产量影响显著。随着播种量的增加,秧苗高度、单株根数、假茎宽、百苗干物质质量及成秧率下降,秧苗个体素质降低,但单位面积秧苗数增加,秧苗成毯性增强,漏插率降低,机插质量提高,大田基本苗及有效穗数增加。产量则表现出随着播种量的增加先增加后降低的趋势,双季早、晚稻实际产量均以100 g/盘(干谷)处理最高。综合来看,机插双季稻适宜播种量(干谷)早稻为100~120 g/盘、晚稻80~100 g/盘。     

机插杂交水稻塑篮播种法最佳播种密度研究

对塑篮播种法不同播种密度条件下培育的秧苗实施机插后进行漏苗率和均匀度合格率测定,参考行业有关机械插秧质量标准,确定最佳播种密度,供大面积实际生产应用时参考.结果表明:以机插漏苗率≤5%,均匀度合格率≥85%为机插质量合格标准,最佳播种密度为240 g/m2.     

杂交稻钵形毯状育秧机插不同播种密度与秧龄研究

以中迟熟杂交稻F优498为材料,对钵形毯状育秧机插的不同播种密度与秧龄进行了研究。结果表明,钵形毯状育秧机插可以显著改善秧苗素质,提高栽插质量和籽粒产量,比常规育秧盘育秧机插增产5.18%～14.80%,其杂交稻的最佳播种密度为60～80 g干种/盘,秧龄可以适当延长至36 d。     

壮秧剂和育秧母质不同用量在早稻机插育秧上的应用效果初探

以早稻温814为材料,进行了壮秧剂与育秧母质不同用量在机插育秧上的应用效果比较试验。结果表明:在施用壮秧剂的情况下,以75 g/m2用量处理的秧苗素质最好,产量最高;而在施用育秧母质的情况下,以1.75 kg/盘用量处理的秧苗长势最好,产量最高。综合考虑秧苗素质和产量性状,采用育秧母质进行育秧更有利于实现水稻高产,推荐用量为1.75 kg/盘。     

播种量对机插稻产量和生物学特性的影响

以两优2186为试验材料,在云南省西双版纳州勐海县进行播种量对机插稻产量和生物学特性的研究。结果表明,播种量为50 g/盘和70 g/盘处理的秧苗素质明显好于90 g/盘、110 g/盘、130 g/盘处理;在栽插时播种量为70 g/盘的缺丛率为13.67%,显著低于播种量50 g/盘的处理,与90 g/盘、110 g/盘、130 g/盘处理差异不显著;随着播种量的增加,机插稻基本苗数显著增加,高峰苗数也显著增加,但有效穗数增加不显著;从产量构成因素和实际产量来看,播种量为70 g/盘的有效穗数、千粒重和成穗率最高,分别为23.13万穗/667 m2、30.09 g和63.5%,实际产量达到865.67 kg/667 m2,在所有处理中最高。在本试验中,杂交籼稻品种70 g/盘的处理,由于秧苗素质高、基本苗适宜、高峰苗较低,产量构成因素协调,产量也最高。因此,每盘70 g是机插稻适宜的播种量。     

单季杂交水稻机插播种量对秧苗生长的影响

为了定量分析单季杂交水稻机插秧盘播种量与秧苗生长的关系,以籼型杂交水稻丰两优6号和籼粳杂交水稻甬优538为试验材料,设置秧盘播种量分别为30、50、70、90、110、130g/盘的6个处理,分析播种量与株高、叶龄、绿叶数与黄叶数、秧苗生长量及其充实度之间的关系。结果表明,随着播种量增加,秧苗素质变差,绿叶数减少,黄叶数增加,叶面积和干物质积累量显著下降,充实度下降。当播种量为50～90 g/盘时,秧苗素质较好,且秧苗开始成毯,有利于水稻机插和后期群体的调控。     

播种方式和播种密度对杂交籼稻机插秧节本增效的研究

【目的】探索机插杂交籼稻稀播育秧秧苗生长特性、栽插质量、产量与效益特点。【方法】以F优498和Ⅱ优498的种子为材料开发并优选条播器后,采用两因素裂区设计,播种方式为主区,播种量为副区。【结果】条播播种均匀度优势明显,24行条播规格效果最佳。播种14 d后,秧苗开始产生分蘖芽,播后17至23 d是分蘖芽发生速率最快时期。随播种密度的增加,成苗率、干物质积累量、根冠比、秧苗充实度、N积累量、分蘖芽发生率、发根力、漏插率都呈降低趋势,同时有效穗数增加,每穗粒数减少,产量先增加后降低。条播相对于散播,秧苗整体素质较好,易形成壮秧,产量较高。【结论】投入与产出综合分析,采用条播方式,播种密度为50 g/盘时,秧苗群体密度和个体优势之间能得到较好的协调,产投比最高。     

云南籼稻小苗机插技术研究

为了降低机插稻育秧、运秧劳动强度,在云南籼稻地区探索籼稻小苗机插技术。以吉优716为材料,设置160 g/盘（T1 ）和180 g/盘（T2）2个播种量处理,秧龄9 d,每667 m²大田用秧6盘。以常规播种量70 g/盘,15 d秧龄,每667 m²用秧15盘为对照,比较分析了不同处理间秧苗素质、栽插质量、茎蘖动态和产量的差异。结果表明,虽然密播小苗处理秧苗素质不如对照,并且缺丛率较高,但每丛基本苗数、各时期的茎蘖数和有效穗数均显著高于对照,最终产量均高于对照。较高的有效穗数是机插密播小苗技术增产的主要原因。其中,T1处理用种量比对照减少了8.57%,秧盘数比对照减少60%,但产量比对照增加了9.0%,节本增效的效果明显,具有较大的推广潜力。     

水肥一体简易场地无盘育秧对机插杂交晚稻秧苗素质的影响

为了探明机插杂交水稻简易场地无盘育秧的可行性和实用性,在湖南农业大学水稻栽培试验基地(浏阳市永安镇)以杂交水稻泰优390、C两优华占为材料,比较研究了不同育秧方式和不同播种方式对机插杂交水稻秧苗素质的影响。结果表明,采用简易场地无盘基质育秧方法,不论是单粒印刷播种还是播种器播种,其秧苗株高、叶龄、植株干重等地上部指标均优于硬盘泥浆育秧。单粒印刷播种条件下,不论是简易场地无盘基质育秧还是硬盘泥浆育秧,其秧苗株高、叶龄、茎基宽、叶绿素含量、植株干重以及根系干重等均优于播种器播种秧苗。由此可见,简易场地无盘基质育秧和单粒印刷播种均有利于提高秧苗素质,两者结合应用对机插杂交稻育秧的发展具有重要意义。     

杂交稻低播量精量播种育秧及机插取秧特性

【目的】明确杂交稻70 g以下低播量精量穴播和条播对育秧效果及机插特性的影响,突破生产中杂交稻机插的技术瓶颈。【方法】以中浙优1号和甬优1540两个杂交稻品种为材料,利用机插标准9寸盘,设置机械穴播和条播两个精量播种方式,并以机械流水线撒播为对照,穴播规格为16(纵向)×34(横向)穴,条播为纵向16条,以穴播5粒、3粒及2粒的播种量进行播种试验。考查了低播量下不同播种方式对秧苗生长影响及配套取秧效果【结果】1)低播量下不同播种方式对秧苗成苗率的影响不大。2)降低播种量提高秧苗生长一致性,且穴播和条播秧苗生长一致性好于撒播。3)与撒播相比,精量穴播和条播能够在低播量下提高秧苗根系盘结力和成毯性,中浙优1号和甬优1540根系盘结力比撒播平均高75.4%和81.0%,播量每穴3粒时即能有效成毯,穴播和条播差异不大。4)精量穴播和条播能够显著降低低播量下机插漏秧率,中浙优1号和甬优1540机插漏秧率平均分别比撒播低76.3%和74.6%,穴播和条播下,两个品种每穴播量3粒的漏秧率均在1%以下,与撒播相比降幅在10个百分点以上。5)精量穴播和条播机插取秧苗数均匀度比撒播要好,两个品种预期取秧2~5苗(5粒)、1~3苗(3粒)和1~2苗(2粒)比例均达80%以上,中浙优1号和甬优1540机插苗数均匀度平均比撒播高121.2%和67.0%,其中,穴播机插取秧苗数均匀度及预期取秧苗数比例高于条播。【结论】精量穴播和条播可以解决目前杂交稻机插用种量大、漏秧率高和机插取秧苗数均匀度差的问题。     

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.     

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.     

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.     

Novel food and non-food uses for sorghum and millets

Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.