应对气候变化 确保冬小麦安全生产

随着全球气候的异常变化．河南省安阳地区年平均气温升高．降水量减少。暖干化趋势明显。水资源供需矛盾加剧．农业气象灾害频繁发生．农业病虫害呈上升趋势．影响小麦生产的不利因素增加。农业气象灾害主要归结于降水因子和温度因子的变化。所以从趋利避害的角度研究小麦生产期间主要天气气候灾害（干旱、作物冷害、冻害、雷雨大风等）对小麦的影响和风险,为防灾减灾宏观调控和风险管理提供科学依据。     

江苏采种甜菜越冬气候及防冻技术的探讨

确定甜菜种株良好气候生态区域,是良种繁育的重要任务。江苏地处中纬度近海,气候、生态等诸因素为我国甜菜南繁采种优越的生产区域。随着科研生产体系的日趋完善,其生产水平、配套技术、品质、产量和效益明显提高,但冻害仍然是采种甜菜高产稳产的主要限制因素。本文仅对江苏采种甜菜越冬气候、冻害指标及防冻技术作初步探讨,为甜菜科研、生产提供农业气候依据。甜菜种株的抗寒性及冻害特征     

江苏沿淮地区中强筋小麦高产优质栽培技术规范

1小麦生产水平基本情况 江苏沿淮地区位于北纬33。线、南北交接地带，以沙壤土为主要土质类型，前茬以迟熟中粳和中熟中粳稻为主，亦有少量棉花、大豆茬口，年度降雨量变幅大，不均匀，易旱易涝。小麦生产水平差异大，高产地区及田块产量达550kg/667m2，低产田块的产量不足350kg／667m2。     

豫东地区小麦冻害的形成特点及原因解析

以1981—2010年度商丘市小麦生长季的气象数据为资料,系统地研究了小麦生育期冻害发生规律,深入地分析了形成原因。研究表明:该区小麦冻害10年10遇,重灾年率为10年8遇。与常年相比,冻害的发生频率呈现变化不大,危害程度呈现冻害有所减轻的趋势;时期呈现冻害初冬和早春逐渐减少,越冬和晚霜逐渐增多的态势;空间分布呈现冻害东部重,西部次之,中部轻的特征。从冻害形成原因上来看,该区每年冬初至春末冷暖空气交替频繁,气候多变,低温灾害性天气多;另外,由于耕层浅、播量过大、水肥管理不适等人为因素也会造成小麦易遭受冻害。     

灾害性天气对小麦产量的影响

近几年在小麦生产中,经常会遇到干旱、冻害以及干热风等自然灾害的影响,对小麦生产影响很大,为有效预防自然灾害的发生,将损失降到最低,现将防御措施总结如下。1干旱不同生育时期干旱对小麦的影响不同,前期干旱主要影响小麦的播种质量进而影响分蘖的发生,对小麦成穗有一定的影响。拔节至孕穗期干旱对幼穗分化影响很大,小穗数和小花数减少,     

南靖县麻竹种植的气象条件分析

根据麻竹对环境气候条件的要求,结合南靖县1981-2010年的气候资料进行分析,证实南靖县麻竹生长期温度适宜,生长旺盛期和盛产笋期水分充足,是种植麻竹的理想地区,但低温冻害、干旱和暴雨等气象灾害频繁发生,尤其是低温冻害是影响麻竹生产的主要气候因素,应加以防范。     

黄淮南片麦区小麦耐倒春寒育种研究初探

倒春寒是严重影响和制约黄淮南片麦区小麦生产的主要气象灾害之一。小麦受倒春寒的危害程度与霜冻天气、栽培条件和品种自身遗传等关系密切。为了给黄淮南片麦区小麦耐倒春寒育种提供参考,本文结合耐倒春寒品种(系)百农矮抗58、百农207等的育种实践,提出判断小麦品种耐倒春寒的4条基本原则:(1)在相同地区相同年份,发生倒春寒时,不同栽培条件下均未发生冻害或冻害较轻的品种;(2)在相同地区不同年份,无论任何生育时期发生倒春寒均未造成冻害或冻害较轻的品种;(3)在不同年份不同地区,发生倒春寒时,均未发生冻害或冻害较轻的品种;(4)在低温敏感期(穗分化时期)鉴定时未发生冻害或冻害较轻的品种。本文还分析了与小麦品种耐倒春寒能力强弱密切关联的冬春性和抽穗期、光温反应特性、植株健壮度、越冬期抗寒性、穗部结实性和受害后恢复能力等6类性状,拟定了小麦耐倒春寒育种的基本方法。     

大小麦早春冻害的发生和防御

概述了大小麦早春冻害的发生及表现形式 ,栽培措施对冻害程度的影响 ,以及冻害的防御和补救措施。     

小麦冻害发生的原因和预防措施

小麦是邢台市的主要粮食作物,常年种植面积35.3万hm2左右,居三大作物（小麦、玉米、棉花）之首。近年来,小麦冻害现象屡屡发生,导致小麦减产。经过几年的调查研究,对小麦冻害产生的原因和预防措施进行了分析总结,旨在为小麦冻害防御提供技术指导,达到提高小麦产量的目的。     

小麦阶段性冻害的生理机制及预防途径研究进展

为系统了解小麦抗寒性研究现状,从遗传、生理、栽培、遥感等方面对小麦阶段性冻害发生的生理机制及预防途径的研究进展进行了总结和评述。小麦抗寒性受多个微效基因控制,低温锻炼激发这些基因,诱导冻蛋白或冷激蛋白的合成和功能表达;低温补偿系统、植株营养以及水分代谢的失衡是小麦冻害发生的主要生理原因;通过品种选择、适当晚播、提高播种质量、合理施肥、生物化学调控可提高小麦抗寒性,减少冻害发生和危害;利用遥感监测可对小麦冻害做出快速有效的评估。     

Characterization of starches of proso,foxtail, barnyard,kodo, and little millets

Scanning electron microscope (SEM) pictures of small millet starch granules showed more large polygonal and few small spherical or polygonal granules. The granules of small millets resembled those of rice starch granules. The size of the starch granules ranged from 0.8–10 m. The size of the granules was larger in barnyard millet and smaller in proso millet. Several granules showed deep indentation caused by protein bodies. SEM of starch isolated from 24 hour-germinated kodo millet showed pitting or pinholes at some points due to the attack of amylases (preferentially on bigger granules). Brabender viscoamylograph studies on small millet starches revealed that the gelatinization temperatures ranged from 75.8 to 84.9 ^° C. Barnyard millet possessed lower amylograph viscosity, minimum breakdown, and relative breakdown values when compared to the other small millets.     

Effects of application of nitrogen fertilizer on concentrations of P, K, S, Ca, Mg, Na, Cl, Mn, Fe, Cu and Zn in perennial ryegrass/white clover pastures in south-western Victoria, Australia

Effects of timing and rate of N fertilizer application on concentrations of P, K, S, Ca, Mg, Na, Cl, Mn, Fe, Cu and Zn in herbage from perennial ryegrass/white clover pastures were studied at two sites in south-western Victoria, Australia. Nitrogen fertilizer (0, 15, 25, 30, 45 and 60 kg ha^–1) was applied as urea in mid-April, early May, mid-May, early June and mid-June 1996 to pastures grazed by dairy cows. At Site 1, N fertilizer resulted in a linear increase in P, K, S, Mg and Cl concentrations in herbage and a linear decrease in Ca concentration. For all times of application, concentrations of P, K, Ca, Mg and Cl in herbage increased by 0·0048, 0·08, −0·010, 0·0013 and 0·053 g kg^–1 dry matter (DM) per kg N applied respectively. For S concentration, maximum responses occurred in mid-May (0·012 g kg^–1 DM per kg N applied). At Site 2, N fertilizer resulted in a linear increase in P, S and Na concentrations in herbage, a linear decrease in Ca concentration and a curvilinear increase in K and Cl concentration. The maximum responses for P, S and K concentrations in herbage occurred for the N application in mid-June and were 0·015, 0·008 and 0·47 g kg^–1 DM per kg N applied respectively. For Cl concentration, the maximum response occurred for the N application in early June and was 0·225 g kg^–1 DM per kg N applied. Overall, applications of N fertilizer up to 60 kg ha^–1 did not alter herbage mineral concentration to levels that might affect pasture growth or animal health.     

Milling,functional and thermo-mechanical properties of wheat,rye, triticale,barley and oat

The milling potential of hulled barley, hulled oat, triticale, rye and wheat was studied using a long tempering process and a laboratory four-roller mill. Regardless of the investigated cereal, the results indicated a significant influence (p < 0.05) of volume per surface area ratio on the milling yield and ash contents of the flour. The lowest milling yield was obtained in case of hulled oat. Solvent retention capacity profiles were determined for all investigated whole cereals and flours for predicting the contribution of different polymers to the functionality of samples. For all solvents higher values were obtained for the whole cereals compared to the corresponding flour. Thermo-mechanical properties of the whole cereals and refined flours were also investigated. If in case of wheat the gluten proteins play an essential role on dough behaviour during kneading at 30 °C, in case of triticale, rye, hulled barley and hulled oat, the fibers play a major role as well. Thermo-mechanical properties of starch registered a large variation between cereals and/or flours. The lowest torque value corresponding to starch gelatinization (C3) was registered in case of the hulled oat flour, 1.92 Nm, while the highest value in case of rye flour, 2.65 Nm.     

Evaluation of the enzyme-amplified ELISA for the detection of potato viruses A,M, S,X, Y,and leafroll

Various parameters,e.g. types of microtiter plate for DAS-ELISA (double antibody sandwich-enzyme-linked immunosorbent assay), use of fresh or frozen amplifier solutions for enzyme-amplified-ELISA, and use of sodium diethyldithiocarbamate (NaDIECA) in sample buffer in cocktail-ELISA were evaluated for the detection of potato viruses A, M, S, X, Y and leafroll from potato foliage. Dynatech Immulon immunoplates provided higher readings for all viruses. Fresh amplifier solution in amplifed-ELISA was superior to frozen solutions. Amplified ELISA gave only marginal improvement in the sensitivity over the standard DAS-ELISA. Addition of NaDIECA in sample buffer did not improve the detection of viruses in DAS-, amplified-, or cocktail-ELISA. Cocktail-ELISA can reduce antigen incubation time to as short as 15 min for PVA, PVM and PVX; 1 hr for PVY and PLRV; and 2–4 hr for PVS using pre-coated plates. Although amplified-ELISA is slightly more sensitive than DAS-ELISA for certain potato viruses, it is not suitable for large-scale indexing of potato viruses in Seed Certification Laboratories, in view of the additional steps needed in carrying out this procedure.     

Study of antimicrobial activity of aloevera, chitosan, and curcumin on cotton, wool, and rabbit hair

Aloevera, chitosan, and curcumin were applied in alone and in combination with each others on cotton, wool and rabbit hair by exhaustion method for the assessment of their antimicrobial activity. The antimicrobial activity of these natural ingredients was better in peroxide treated cotton, formic acid treated wool/rabbit hair fibrous substrates than their corresponding intact ones. Aloevera shown better antimicrobial activity than chitosan and curcumin when applied alone and its antimicrobial activity was enhanced by addition of both chitosan and curcumin. The application of aloevera+chitosan+curcumin combination on peroxide treated cotton and formic acid treated wool/rabbit hair fibrous substrate was fast up to twenty five washing cycles.     

Response of permanent and reseeded grassland to fertilizer nitrogen. 2. Effects on concentrations of Ca, Mg, K, Na, S, P, Mn, Zn, Cu, Co and Mo in herbage at a range of sites

The concentration of mineral elements in herbage from permanent swards of mixed species composition (predominantly Agrostis spp., Holcus lanatus, Festuca rubra, Lolium perenne, Poa spp., etc.) was compared with that from sown perennial ryegrass ( Lolium perenne ) at two fertilizer rates (0 and 300kg N ha⁻¹ year⁻¹, both with P and K) and with L. perennel Trifolium repens (at 0 N with P and K). The investigation was conducted over four years at sixteen contrasting sites in England and Wales. Herbage samples for mineral analysis were taken at first and fourth harvests (May and August) each year from plots under 4-weekly cutting. There was a wide degree of variation between sites, particularly for concentrations of Ca, Mg, Na and all trace elements analysed. Herbage from L. perenne reseeds had significantly higher concentrations of Ca, Mg, Na, Co and S, but K, Mo, Zn, Cu and P were generally lower than in the permanent swards. L. perennel T. repens swards had the highest concentration of major cations, but trace element levels were generally intermediate between those for 0 N permanent and L. perenne swards. Fertilizer N reduced concentrations of Ca, Mn, Mo and S, and increased Mg, Na and Zn, with no consistent effects on K, Co and Cu. Herbage at harvest 4, compared with harvest 1, had higher Ca, Mg, Na, Mn, Zn and S. Permanent and L. perenne swards responded similarly to fertilizer N and between harvest dates. Results are discussed in relation to previous reports of botanical and fertilizer effects on mineral concentrations, and the mineral requirements of livestock. Changes in mineral concentration resulting from reseeding permanent swards are considered unlikely to increase mineral-related livestock disorders, and in many cases could be beneficial, though problems might arise on sites where some elements, e.g. Cu and Mg, are low.