Compatibility of root growth and tuber production of potato cultivars with dynamic and static water‐saving irrigation managements          下载免费PDF全文

S. H. Ahmadi  M. Agharezaee  A. A. Kamgar‐Haghighi  A. R. Sepaskhah 《Soil Use and Management》2017,33(1):106-119

The important root characteristics of root length density (RLD) and root mass density (RMD) generally differ among irrigation managements and potato cultivars. The objective of this study was to investigate the RLD and RMD variations and their functional relationships with gross potato tuber yield for two commercial potato cultivars, Agria and Sante, under different irrigation strategies. Full irrigation and water‐saving irrigation strategies, deficit and partial root drying irrigations, were applied statically (S) and dynamically (D) based on daily crop evapotranspiration. Results showed that SPRD had significantly greater RLD (3.64 cm/cm³) and RMD (132.7 μg/cm³) than other irrigation treatments. Between the potato cultivars, Agria had significantly larger values of RLD (3.50 cm/cm³) and RMD (138.7 μg/cm³) than Sante. The functional relationship between the root growth characteristics and tuber yield showed that under water‐saving irrigations, Agria increased root mass at the expense of gross tuber yield but Sante increased root mass to maintain larger gross tuber yields. However, Agria produced more roots and gross tuber yield than Sante, and it is concluded that Agria is a more drought‐tolerant potato cultivar, which is recommended for tuber production in regions where water might be scarce. It was shown that larger root production in potatoes was associated with improved tolerance to water stress.  相似文献   

捕食线虫性真菌的分离培养及分布规律   总被引：6，自引：1，他引：5  

杨晓野  杨莲茹  刘珍莲  董世娟  考桂兰 《中国兽医学报》2003,23(4):344-347

对自然界中的捕食线虫性真菌进行了分离和种属区分，并对分布规律进行了研究。从土壤、粪便等材料中获得了2类活性较强的捕食线虫性菌株：即套捕型(hooping)捕食线虫性真菌和粘捕型(sticking)捕食线虫性真菌。主要的代表种类有3种。这些捕食线虫性真菌在捕食性结构分生孢子形态及某些生物学特性上有一定差异。套捕型捕食线虫性真菌代表种为少孢节丛孢菌(Arthrobotrys oligospara)和梨形指环菌(Dactylaria pyriformis)，它们以菌环、菌网作为捕食性结构(器官)，以套捕方式杀灭线虫幼虫。梨形指环菌可产生多量厚垣孢子(chlamyalospore)。粘捕型捕食线虫性真菌代表种为纺锤隔指孢菌(Dactylella ellipsospora)。可形成菌结捕食线虫性结构，以粘捕的方式杀灭线虫幼虫。结果表明：捕食线虫性真菌在土壤和家畜粪便中的分离率是40．41％；此类菌适合于生存在阴暗、潮湿、富含腐植质的环境中。在温暖季节时，采用0．4g／L玉米粉琼脂培养基(CMA)易于对其进行分离培养。  相似文献   

捕食线虫性真菌菌种保存技术的研究     

考桂兰  石鑫  杨晓野  杨莲茹  刘珍莲  王军 《中国预防兽医学报》2004,26(5):385-388

本试验对捕食线虫性真菌菌种保存技术进行了研究,测定了在不同介质保存条件下,捕食线虫真菌分生孢子和菌丝的存活情况及其不是寄生性线虫的能力.结果表明:在设定的保存条件下,分别经过1周冷冻融化或2周反复冷冻融化,被保存的分生孢子接种于玉米粉琼脂培养基上能生长发育:在加入线虫第3期幼虫后,能生产捕食器,对虫体发挥捕食作用.  相似文献   

The Phytotoxicity of Various Graminicides in Durum Wheat in Greece     

D. Bilalis  P. Efthimiadis  & G. Karagiannis 《Journal of Agronomy and Crop Science》2001,187(2):121-126

The effect of three herbicides, diclofop-methyl (DM), imazamethabenz-methyl (IM) and fenoxaprop-ethyl (FE), was investigated at the recommended rate (×) and double the recommended rate (2×) in a durum wheat crop. FE had the smallest effect on root system characteristics, while IM had the greatest effect. For all herbicides, the double rate treatment gave a greater statistical reduction than the single rate for root system characteristics. FE had the smallest effect on the activity of aerobic microorganisms, while DM gave the greatest reduction, 10 days after application, and all three herbicides reduced earthworm abundance. DM gave the smallest reduction in the number of tillers and in plant height, while the double rate of IM gave the greatest reduction. For all three herbicides, double the recommended rate resulted in a significant reduction in the weight of 1000 seeds, while no statistically significant deviations were noted at the recommended rate. Finally, the use of all three herbicides resulted in significantly lower statistical yields compared to the sample (control plot), although there were no significant statistical differences among them, for either recommended or double recommended rates.  相似文献   

苹果试管苗不定根起源及其发育状况的研究   总被引：4，自引：0，他引：4  

马俊戏  陈四维 《河北农业大学学报》1992,15(4):46-50

利用光学和扫描电子显微镜观察结果表明,经琼脂生根培养基诱导产生的长富—2苹果 (Malus pumila Mill.) 试管苗的不定根起源于维管形成层。这种不定根发育不良,根表面缺乏根毛,内部解剖构造为典型的初生结构。为避免因不定根吸收、运输能力差而影响试管苗移栽成活,宜采用通透性良好的基质进行瓶内或瓶外生根,可诱导出优质不定根。  相似文献   

胃肠道线虫的黏膜免疫     

韩周路义鑫  宋铭忻 《中国兽医科技》2006,36(8):679-683

从机体抗胃肠道线虫的黏膜免疫、胃肠道黏膜的抗原加工与递呈、胃肠道黏膜抵御寄生虫的效应机制等几方面论述了胃肠道线虫的免疫机理和免疫学研究的进展，旨在进一步阐明用免疫介入方法防治胃肠道线虫的理论基础，以解决胃肠道线虫治疗过程中的药物残留以及寄生虫的抗药性问题。  相似文献   

Horizontal transmission and host-virulence attenuation of totivirus in violet root rot fungus Helicobasidium mompa     

Kouichi Suzaki  Ken-ichi Ikeda  Atsuko Sasaki  Satoko Kanematsu  Naoyuki Matsumoto  Kouji Yoshida 《Journal of General Plant Pathology》2005,71(3):161-168

Monokaryotic strains of Helicobasidium mompa were used as vectors of a mycovirus between various H. mompa isolates to examine the transmissibility of one of the mycoviruses, totivirus (HmTV1–17 virus) in the hypovirulent isolate V17 of H. mompa. The isolates that acquired HmTV1–17 virus were also examined for any alteration in the virulence. Twelve dikaryotic isolates of H. mompa, belonging to 11 mycelial compatibility groups (MCGs) and being mycelially incompatible with isolate V17, were used as recipients of HmTV1–17 virus. Two monokaryotic isolates that were mycelially incompatible with isolate V17 and all of the recipients were also used as vectors of HmTV1-17 virus between isolate V17 and the recipients. When isolate V17 and recipients were directly paired on plate media, HmTV1-17 virus was transmitted from isolate V17 into 2 of the 12 recipients (i.e., 2 of the 11 MCGs). Two monokaryotic strains were paired with isolate V17, and the monokaryotic strains that acquired HmTV1-17 virus were then used as new virus donors. When the monokaryotic strains containing HmTV1-17 virus were paired with the 12 recipients, HmTV1-17 virus was transmitted into 7 of the 12 recipients from the monokaryotic strains (i.e., 7 of 11 MCGs). Based on these results, we concluded that monokaryotic strains could act as vectors to transmit HmTV1-17 virus into H. mompa isolates. When four of the H. mompa isolates that acquired HmTV1-17 virus were used to inoculate apple rootstock Malus prunifolia, the virulence of all of the isolates was attenuated from that of their parental isolates. Moreover, because the DNA fingerprints of the fungal isolates that acquired HmTV1-17 virus were the same as those of their parental isolates, the infection with HmTV1-17 virus is considered the cause of virulence attenuation of H. mompa.  相似文献   

Fusarium oxysporum对苗期大豆根部的致病性和侵染规律     

韩庆新  辛惠普 《黑龙江八一农垦大学学报》1989,(1):113-119

Fusarium oxysporum对苗期大豆具有较强的致病作用。病原菌自伤口或直接侵入大豆幼苗根部的皮层组织,随着病原菌的侵入和扩展,细胞出现坏死,组织发生崩解,根部组织表现红褐色病斑。环境因素对病原菌的侵染时期和在大豆体内潜育时间的长短有着明显的影响。侵染时期主要受病原菌侵入前自身所处状态和寄主的影响,侵入后潜育时间的长短则受植株状态的影响。土壤环境条件直接影响着病原菌的侵入和寄主的抗病性,间接影响着病原菌在大豆植株体内的扩展和病症的表现。  相似文献   

The Effect of Detopping the Field Bean Plants (Vicia faba L. minor) and Lack of the Pod Setting on the Symbiosis with Root Nodule Bacteria     

W. Filek    F. Dubert  M. Kaminski 《Journal of Agronomy and Crop Science》1996,176(1):39-45

The plants of field bean var. Nadwiślaνski were detopped after about 1 month since the beginning of flowering and after that all flower buds were removed from some plants. The effect of a change in the trophic balance on the setting and subsequent growth of root nodules was studied.
The removal of pods had the greater effect on the increase in the weight of the remaining organs than the detopping of plants. Detopping retarded the ageing of the plants and delayed the phase of the greatest reduction of the number of pods. The detopping of plants revealed their considerable compensative possibilities in terms of production of the pod weight and the potential of leaves for biomass production. The data obtained indicate that plant detopping may disturb the root–bacteria exchange of signals, necessary to initiate the nodule development, while the further growth of nodules depends, above all, on the amount of available photosynthates.
A very high correlation between the dry weight of the whole plant to the dry weight of leaves ratio and the weight of nodules was observed. It proves the importance of the trophic balance of the plant for the root nodule weight production.  相似文献   

Spring invasion of Heterodera schachtii in sugarbeet; a simulation study     

W. Van Der Werf  R. Rabbinge  W. Heijbroek 《European journal of plant pathology / European Foundation for Plant Pathology》1986,92(1):33-42

A simulation model was developed for the spring invasion of the beet cyst nematode,Heterodera schachtii Schmidt, into sugarbeet roots, according to the state variable approach. This model describes the processes of egghatch, emergence of second stage larvae from cysts, migration to roots and penetration into roots quantitatively, using published data.In 1983 a field experiment was conducted to test this model.H. schachtii cysts were introduced at depths 6–29 cm in PVC-cylinders, buried in the soil. The rooting depth of sugarbeet seedlings, growing in these cylinders, was limited to 5 cm by 50 m mesh nylon gauze. Every 10 days the second stage larvae, which had penetrated into the roots of these seedlings were counted. After 50 days, about 40% of the eggs had hatched. More than 20% of the emerged larvae penetrated if the cysts had been buried undeeply, and only 4% if the cysts had been buried at 29 cm depth.The model predicted the course of penetration into the root during the first 40 days with reasonable accuracy (r²=0.79), but in the 5th period of 10 days the model made an overestimation of more than 100%. Egghatch after 50 days was correctly simulated. The differences in penetration into the root between the model and the experiment might result from an oversimplified simulation of the penetration success or the neglection of mortality of second stage larvae. Detailed experiments should be done to provide better parameters for these factors.Samenvatting Volgens de toestandsvariabele-benadering werd een simulatiemodel ontwikkeld van de voorjaarspenetratie van het bietecystenaaltje. Het model beschrijft aan de hand van literatuurgegevens het uikomen van de eieren, het verlaten van de cyst door de larven, de migratie naar en de penetratie in de wortel.In 1983 werd een veldproef uitgevoerd om het model te toetsen. Cysten vanH. schachtii werden op 5 dieptes tussen 6 en 29 cm ingegraven in PVC-cylinders, welke waren verzonken in de bodem. De bewortelingsdiepte van de suikerbiete-zaailingen die hierin groeiden werd beperkt tot 5 cm door nylon gaas van 50 m maaswijdte. Elke 10 dagen werden de larven geteld die in de wortels van deze plantjes waren gepenetreerd. Na 50 dagen was 40% van de eieren uitgekomen. Meer dan 20% van de gelokte larven penetreerden als de cysten ondiep waren ingegraven, en slechts 4% als de cysten op 29 cm diepte waren ingegraven.Gedurende de eerste 40 dagen werd het verloop van de penetratie in de wortel met redelijke nauwkeurigheid door het model voorspeld (r²=0.79). In de 5e periode van 10 dagen maakte het model echter een overschatting van meer dan 100%. Het uitkomen van de eieren werd correct gesimuleerd. De verschillen in penetratie tussen het model en de proef zouden het gevolg kunnen zijn van een oververeenvoudigde simulatie van het penetratiesucces of van het verwaarlozen van de mortaliteit van de migrerende larven. Betere gegevens hierover zullen moeten komen uit detailproeven.  相似文献