首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Climate Change and Its Repercussions for the Potato Supply Chain   总被引:1,自引:0,他引:1  
Since the onset of the industrial revolution, in 1750, the concentration of carbon dioxide rose from 290 to 380 parts per million. Especially during the last decennia, the effects of increased greenhouse gases concentrations are being felt. The last 14 years worldwide contained the warmest 13 years since weather recording started. For southern Europe, the major effects reported by the International Panel on Climate Change are reduced water availability and a shorter suitable winter time slot for potato production. For northern Europe, climate change will bring a decreasing number of days with frost and a lengthening of the growing season. It will be associated with more rain in winter and less in summer, with more erratic but heavier rain storms. For potato production in Mediterranean and Sahelian types of climate, during the heat-free period of the year, yields will go down as the suitable period becomes shorter. With a higher evaporative demand, the resource water will be used less efficiently. Potato yields in temperate climates may increase—provided that water for irrigation is available—due to a longer growing season and higher carbon dioxide concentrations in the air. The quality may be affected as larger tubers with a higher dry matter concentration are expected. Problems with pests and diseases are expected to increase with a longer growing season at higher temperature which allows more cycles of multiplication and greater pressure. Late blight will also have a longer period to build up and erratic rains will make control more difficult. Seed production with increased vector pressure will become more costly because fewer field generations will follow the rapid multiplication stage and seed production may move further north. Present potato areas in Europe, however, are more affected by economic factors such as inadequate farm size, changing habits, and remoteness of markets than by climate determined suitability of growing conditions. To remain competitive, the industry will have to invest in strengthening existing production areas and assess the potential of new potato production areas (further north), in new varieties adapted to extremes in weather (heat, drought), in irrigation equipment, in equipment better adapted to wet soil conditions to assure accessibility, and in improved stores with more stores equipped with refrigeration as higher winter temperatures more frequently will make it impossible to keep ware potatoes cool with ambient air. Assessment of both climate change and market liberalization in Europe shows other roads ahead than when only climate effects are taken into consideration.  相似文献   

2.
Molecular farming refers to the production ofrecombinant proteins in heterologous expressionsystems.The recent advances in genomics andproteomics resulted in identification of several newgenes.These have to be functionally characterized toexplore their probable use in diverse applications.Itis quite unlikely that a single expression system couldsupport the production of these proteins,thereforethere is a needtoidentifyandanalyzedifferentnovelex-pression systems for the recombinant protein prod…  相似文献   

3.
4.
马铃薯早熟品种选育的实生籽播种期研究   总被引:1,自引:0,他引:1  
前 言中原二季作地区马铃薯生产需要选用早熟或中早品种 ,中、晚熟品种在这一地区产量非常低 ,甚至没有产量。其主要原因是这些品种生长期长 ,结薯所需要的环境条件比较严格。在中原地区 ,春季马铃薯播种出苗后日照时数逐渐增多、气温逐渐增高 ,不利于中、晚熟品种结薯。 6月中旬以后高温雨季到来 ,结薯和块茎膨大受到影响 ,同时植株开始感病 ,不等植株正常成熟就已死亡。因此 ,在品种选育上应根据这一地区的特点选育早熟、休眠期短、结薯对温度、光照长短不敏感、秋季播种耐高温的株系。中原地区在利用杂交实生籽育种工作中 ,由于受长日照…  相似文献   

5.
6.
7.
Posidonia oceanica (L.) Delile is a Mediterranean-endemic angiosperm often described for its great ecological importance. Despite evidence of a millennia-old relationship between P. oceanica and humans, as well as traditional medicine applications, the potential benefits of P. oceanica for human health have been documented only recently. This review aims to compile newly acquired knowledge on P. oceanica bioactive properties that allow the scientific community to look at this plant as a promising source of natural therapeutical products for human health. Experimental investigations conducted in both in vitro cellular-based and in vivo animal models pave the way for new research projects aiming at the development of alternative and complementary therapeutic strategies based on P. oceanica against a wide range of pathological conditions.  相似文献   

8.
Field studies were conducted in 2008 and 2009 in Aberdeen, ID, Ontario, OR, and Paterson, WA to determine the effect of simulated glyphosate drift on ‘Ranger Russet’ potato during the application year and the crop growing the next year from the daughter tubers. Glyphosate was applied at 8.5, 54, 107, 215, and 423 g ae ha?1 which corresponds to 1/00, 1/16, 1/8, ¼, and 1/2 of the lowest recommended single-application rate for glyphosate-resistant corn and sugar beet of 846 g ha–1. Glyphosate was applied when potato plants were at 10 to 15 cm tall (Early), or at stolon hooking (H), tuber initiation (TI), or during mid-bulking (MB). In general, the MB applications caused less visual foliar injury to the mother crop than earlier applications at ID or OR, and H applications at WA. Mother crop injury increased as glyphosate rate increased regardless of location, application timing, and rating date. U.S. No.1 and total tuber yields were usually related to the injury level resulting from glyphosate application timings and rates. Although injury to the mother crop from glyphosate applied at MB usually was the lowest compared to injury from other application timings, when daughter tubers from that timing were planted the following year, emergence, plant vigor, and yield was most detrimentally impacted compared with that of daughter tubers from other timing treatments. MB daughter tuber emergence was less than 30 % of the nontreated control tuber emergence while emergence of daughter tubers from the other treatments was 60 to 95 %. As rate of glyphosate applied to the mother crop increased, daughter tuber emergence decreased. When MB daughter tubers did emerge, plants were chlorotic and stunted as if the plants had been directly sprayed with glyphosate. Regardless of whether the daughter tubers had defects or not, results the following year were the same. Implications are that if a mother seed crop encounters glyphosate during bulking, injury may not even be noticeable on the foliage or the tubers, however, emergence, vigor, and yield of the crop growing the following year from the daughter tubers could be greatly impacted.  相似文献   

9.
10.
11.
12.
轮作是防治大豆胞囊线虫病的有效措施,旨在探讨常用和潜在的轮作植物对大豆胞囊线虫病的抑制作用.为黑龙江省大豆生产轮作体系改进提供技术支持.2006年,选择5种轮作植物(大麦、红三叶草、万寿菊、亚麻、玉米)与感病品种一起种在大豆胞囊线虫病圃;2007年种植玉米、小麦和感病大豆.检测两年播种前和收获后土壤中大豆胞囊线虫胞囊、卵和二龄幼虫数量;2008年所有小区种植感病大豆,测定大豆产量.结果表明:连续种植大豆的处理卵数量增加了13%,而种植万寿菊、红三叶草和大麦茬后复种红三叶三个处理的土壤中卵的数量明显减少,减少率分别为80%、58%和68%,其他轮作处理土壤中大豆胞囊线虫群体密度也有不同程度降低,而且,轮作区大豆产量也有提高.结果显示:合理种植万寿菊、红三叶草以及大麦后复种红三叶草可以减少土壤中胞囊线虫的密度,对大豆胞囊线虫的抑制作用好于常规轮作作物玉米.而综合考虑不同作物对土壤养分的影响,以及在黑龙江省的播种面积,则可以确定能够使土壤中胞囊线虫密度减少,同时义能够提高土壤养分的合理的轮作方式为万寿菊一玉米一大豆.  相似文献   

13.
作物抗旱性生理生化机制的研究现状和进展   总被引:28,自引:0,他引:28  
根据现有文献资料,从渗透调节、细胞膜的结构和功能、自由基学说、干旱胁迫下特异蛋白的产生及其生理功能等方面综述了作物抗旱性生理生化机制的研究现状和进展。  相似文献   

14.
Effects of Aeration on Root Physiology and Nitrogen Metabolism in Rice   总被引:2,自引:0,他引:2  
In order to clarify the effects of aeration on root nitrogen metabolism in rice seedlings,rice cultivars Guodao 6 (indica) and Xiushui 09 (japonica) were investigated for root growth,the activities of glutamine synthetase (GS),glutamic acid-pyruvic acid transaminase (GPT) and glutamic acid oxaloacetate transaminase (GOT),the nitrate (NO 3-N) concertration,the contents of free amino acids and soluble sugar in root under hydroponics with continuous aeration treatment.The results showed that rice seedlings grown in oxygenation solutions had higher root dry matter,longer root length,stronger root activity and larger root absorption area compared with the control.In addition,the contents of soluble sugar,root vigor and the activities of GS,GOT and GPT in the aeration solutions were higher than those in the control.The results also indicated that the activities of enzymes involved in root nitrogen metabolism of Xiushui 09 were enhanced by aeration,however,there was no significant influence on root nitrogen metabolism of Guodao 6,which suggested that effect of oxygenation on rice root nitrogen metabolism might be genotype-specific.  相似文献   

15.
The perennial herb Chlorophytum nepalense (Lindley) Baker, widely distributed throughout the northern parts of Tripura State of India, is used traditionally by Tripuri farmers as a root extract to control dark viral necrotic lesions of sprouted potato tubers and plants. The root extracts strongly reduced infection of potato plants and sprouted tubers by Potato virus X under glasshouse conditions. The root extract was found to contain the three plant-viricidal compounds chlorogenic acid, kaempferol-3-O-(3′,6′di-O-E-p-coumaroyl)-β-d-glucopyranoside, and luteolin and suggests that the isolated compounds may have the potential to be used as natural plant-viricidal compounds.  相似文献   

16.
夏镇卿  路海东 《玉米科学》2020,28(3):99-104
土壤温度对作物的生长发育具有很强的调控作用。在全球气候变化背景下,根区土壤温度对玉米生长的影响及其调控机制已成为当前研究的一个热点。结合目前农业生产中土壤低温和高温对玉米造成危害的现状,从土壤温度对作物根区土壤环境以及玉米根系生长、冠层发育与产量形成的影响方面,综述土壤温度对玉米生长发育调控作用的研究进展,介绍改变土壤温度的措施以及对玉米土壤温度研究的发展方向进行展望,为今后的研究提供参考。  相似文献   

17.
When we consider complex, multi-step processes such as crop growth or the progress of a disease then simple mathematical functions are inadequate to describe them and we generally use some kind of mathematical model. The commonest form in use is one that we call a simulation model although there are other forms of model such as Rule-based, (e.g. Gu et al. AI Appl 10:13–24, 1996), Bayesian (Gold, Plant Disease Epidemiol 4:84–122, 1989) and ‘fuzzy’ (Burrough, J Soil Sci 40:477–492, 1989), depending upon the application. Models may sometimes be combined into packages that we call decision support systems. This paper will consider simulation modelling and also the combination of complementary models. Mathematical models of the potato crop have been devised, in a range of sophistication, over a long period of years and a quite proper question is: “Where next? What are the developments that are sought or, more importantly, that are needed?”  相似文献   

18.
Sustainable management of phosphorus (P) is a critical component of potato production systems because of a comparatively high plant P requirement, soil reactions that create management challenges, and potential environmental degradation from inappropriate P management. Phosphorus affects potato plant growth in many ways including its effects on plant metabolism, cellular structural components, canopy development, tuber set, nutritional quality, and resistance to some diseases.  相似文献   

19.
马铃薯低温贮藏造成还原糖积累是影响块茎加工品质最重要的因素,有关低温糖化机理一直是马铃薯品质改良研究的热点。本文总结了马铃薯基因型、环境因子、ABA和生物膜组成变化对还原糖积累的影响,重点从生理生化水平上探讨了块茎碳水化合物代谢路径变化与还原糖积累的关系,为抑制还原糖含量改良块茎品质打下了理论基础。  相似文献   

20.
Abstract

Rice (Oryza sariva)-wheat (Triticum aestivum) rotation is the major production system in the Indo-Gangetic plains of South Asia and mid hills and is important for the food security of the region. The productivity and profitability of the rice-wheat system are very low mainly because of inappropriate nutrient input and poor crop management practices. Field experiments were conducted in 21 farmers' fields in Bara and Parsa districts in the Eastern-Gangetic plains of Nepal from May 1999 to April 2002 to evaluate site-specific nutrient management (SSNM) and integrated crop management (ICM) for improving rice-wheat productivity and profitability. Soil nutrient-supplying capacity (based on omission plot method) varied largely among farmers' fields. Rice soil had a higher N, P, and K-supplying capacity (35–76, 8–17, and 63–98 kg ha1, compared with wheat (16–41, 6–12, and 20–104 kg ha1, respectively). Both SSNM and ICM strategies significantly improved the grain yields of rice and wheat. Overall yield increment by ICM over farmers' practice (FP) reached up to 2.3 Mg ha1 (66%) in rice and 2.3 Mg ha1 (87%) in wheat, suggesting that there is a large potential for increasing rice and wheat yields in Nepal. Yield gap 1 (maximum attainable yieldaverage yield in ICM) was 1.3 to 1.4 Mg ha1 for rice and 0.3 to 1.0 Mg ha1 for wheat. While yield gap 2 (maximum attainable yieldaverage yield in FP) ranged from 2.8 to 3.5 Mg ha-1 for rice and 2.3 to 2.8 Mg ha-1 for wheat. Rice N-use efficiencies increased up to 50% and 70% with SSNM and ICM, respectively, over FP. In wheat, N-use efficiency increased up to 46% by ICM over SSNM. The net profit gained by applying ICM over FP was higher in wheat (US$ 217) than in rice (US$ 73). The findings suggest the urgent need to develop an effective program for wider dissemination of ICM technology in the Eastern-Gangetic plains.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号