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1.
花生品种(系)叶部病害综合抗性鉴定   总被引:4,自引:3,他引:4  
:1 998~ 1 999年在自然发病条件下对 2 0个花生品种 (系 )进行叶部病害综合抗性鉴定。结果表明 ,目前我国广泛种植的花生品种对晚斑病、早斑病、网斑病等主要叶部病害的抗性存在差异 ,缺乏高抗和兼抗性材料。花生对叶部病害的抗性与主茎高、分枝数、结果数、饱果率等农艺性状及其分类类型无显著相关。自然发病条件下花育 1 7和花育 1 6荚果产量较高 ,引进花生品种 UF91 1 0 8产量较低 ,但对晚斑病、网斑病等具高抗水平 ,可提供花生育种作抗源材料  相似文献   

2.
Poor survival of winter cereals due to winter conditions in Ontario can necessitate destruction of the stand in the spring to allow the subsequent seeding of an alternative crop. Winter cereals were seeded in the autumn of 2004 and 2005 at the Huron Research Station and at the University of Guelph Ridgetown Campus in Ontario to evaluate two formulations of glyphosate [potassium (K) vs diammonium (DA) salt] at different doses (225, 450, 675, 900, or 1350 g a.e. ha−1) for the burn-off of soft white winter wheat (SWW), soft red winter wheat (SRW), hard red winter wheat (HRW) and autumn rye (AR) in either late April or early May. There was no difference between the glyphosate formulations for the control of winter cereals at 1, 2, 3, and 4 weeks after treatment (WAT). There was generally improved control with glyphosate applications made in early May compared to late April however results were not always statistically significant. Generally, control of winter cereals increased as the glyphosate dose was increased from 225 to 1350 g a.e. ha−1. The minimum dose of glyphosate required for providing 90% or greater control of SWW, SRW, HRW, and AR was 675 g a.e. ha−1 at 4 WAT. Glyphosate applied at 675 g a.e. ha−1 caused a 98, 97, 98, and 99% reduction in shoot dry weight of SWW, SRW, HRW, and AR, respectively. Based on this study glyphosate (K or DA) applied in late April or early May can be used at doses as low as 675 g a.e. ha−1 to adequately control SWW, SRW, HRW, and AR in the spring.  相似文献   

3.
Scenarios of climate changes indicate longer and more frequent spells of mild weather during winter in northern latitudes. De-hardening in perennial grasses could increase the risk of frost kill. In this study, the resistance to de-hardening of different grass species and cultivars was examined, and whether the resistance changes during winter or between years, was tested. In Experiment 1, two cultivars of timothy ( Phleum pratense L.) and perennial ryegrass ( Lolium perenne L.) of contrasting winter hardiness were grown under ambient winter conditions, transferred from the field in January and April 2006 to the laboratory for 9 d with controlled de-hardening conditions of 3°C, 9°C and 15°C. The timothy cultivars were tested at 3°C, 6°C and 9°C in a similar experiment (Experiment 2) in January 2007. De-hardening, measured as decrease in frost tolerance (LT50), was less in timothy than in perennial ryegrass and increased with increasing temperatures. The northern winter-hardy cultivar Engmo of timothy de-hardened more rapidly than the less-hardy cultivar Grindstad, but had higher initial frost tolerance in both experiments, whereas there was less difference between cultivars of perennial ryegrass in Experiment 1. Cultivar Grindstad of timothy lost all hardiness in early spring at all temperatures, whereas cultivar Engmo maintained some hardiness at 3°C. Cultivar Engmo de-hardened at a lower rate in 2007 than in 2006, in spite of similar frost tolerance at the start of de-hardening treatment in both years. This indicates that the rate of de-hardening was controlled by factors additional to the initial frost tolerance and that autumn weather conditions might be important for the resistance to de-hardening.  相似文献   

4.
Endemic fungal foliar diseases, such as leaf blight – LB [Lasiodiplodia theobromae (Pat.) Griffon and Maubl] and leaf verrucosis, or “lixa-pequena” – LP [Camarotela torrendiela Batista (Bezerra) and Vitoria], reduce the productivity of the coconut palm in Brazil. Damage arises from extensive necrosis of the leaflets, resulting in early abscission of basal leaves and fruit. In Brazil, fungicide terrestrial sprayings has not been a commonly employed practice for the control of coconut foliar diseases because it is not cost-effective, once requiring high-volume of fungicide spraying. Coverage gaps and extensive drift of chemicals can occur due to technological limitations of terrestrial spraying of the tallest mature trees and is further complicated by the peculiar architecture of the palms. The aim of this study was to evaluate the efficacy of systemic fungicides applied directly to the leaf axil of the coconut palm (variety Brazilian Green Dwarf of Jiqui) for the control of foliar diseases. During 2007–2010 and 2009–2012, two field plot experiments were conducted at distinct locations (farms) in the North Fluminense region. Two to 4-monthly applications of the fungicides to the leaf axil of cyproconazole (alone), cyproconazole plus azoxystrobin, cyproconazole plus trifloxystrobin, and flutriafol (alone) were efficacious in controlling coconut palm leaf diseases, resulting in a significant reduction of the LB severity and the number of necrotic LP lesions. When compared with the control treatment, significant increases in the total number of leaves per plant were observed for the most efficacious treatments after one year (2–4 leaves more) and after the second year (3–6 leaves more) after initiating the axillary applications of fungicides in both experiments. This trend continued even after the third year, when there was an average of 8 leaves more for the most efficacious treatment (27 leaves per plant) compared to control (19 leaves per plant) at the end of second experiment. The control of foliar diseases based on the results could ensure a significant increase in regional coconut production.  相似文献   

5.
《Field Crops Research》1998,58(3):167-175
Wheat (Triticum aestivum L.) is expanding into lower latitudes of the Nile Valley Region, where maximum air temperature can reach 38–40°C during the short growing season. Genotype and environment, particularly temperature, affect the rate of leaf appearance. Field experiments were conducted at the Gezira Research Station, Wad Medani, Sudan in 1992–94. The study aimed to determine the effect of high temperature (by manipulating sowing dates) on leaf and tiller appearance and growth of nine spring wheat cultivars. Linear response was found between rate of leaf appearance and thermal time and it was faster before double-ridge stage than after double ridge. Phyllochron ranged between 99°C d and 122°C d. Differences in phyllochron interval (PI) were pronounced among cultivars and early-maturing cultivars had faster leaf appearance compared with late-maturing ones. Mean final leaf number on the main stem ranged from 8.1 to 12.2 and it was highly correlated with thermal time from sowing to double ridge stage (r=0.71**). Genetic constitution of cultivars had larger effect on number of leaves per main-stem than temperature. Tillers were initiated at leaf stage 2.9 and cultivars differed in their tillering capacity and only 1.5–2.0 reproductive tillers per plant were produced. About 810°C d were needed to produce tillers 1 and 2 and about 1140°C d for tillers 3 and 4. Leaf senescence started at leaf stage 6.1 for cv. Wadi El Neil and 4.2 for Debeira. Cultivars sown late exhibited delayed senescence of their leaves. High temperature accelerated maturity and the cultivars suited for the irrigated tropical environment were found to be early-sown late-maturing types.  相似文献   

6.
对5%氨基寡糖素等6种茶树常用叶面肥开展春茶品质和效益影响研究。结果表明,氨基寡糖素等6种叶面肥处理对春茶感官品质影响不明显;氨基寡糖素和利果美处理春茶水浸出物含量提高;氨基寡糖素、利果美、中茶早、碧护、绿康壮、爱多收处理春茶茶多酚含量均有所提高而游离氨基酸却有所降低;中茶早、碧护和绿康壮处理的春茶咖啡碱含量提高;扣除叶面肥使用工本后,6种叶面肥中只有氨基寡糖素和利果美处理春茶收益极显著高于清水对照,每667m~2分别增收1922.9元和941.6元。  相似文献   

7.
Summary True potato seed production may contribute to the spread of several diseases and pests. MCPA (500 or 750 g a.i. ha−1) applied at early or full bud stage reduced berry number and seed number per berry, resulting in reduced true seed production. Effects on berry set differed between cultivars and were dependent on crop growth stage at application and true seed production was reduced most strongly in all cultivars with application at full bud stage. MCPA also slightly reduced yield and tuber size, but did not affect tuber dry matter content or fry colour.  相似文献   

8.
《Crop Protection》1988,7(3):207-209
Fungal diseases of spring wheat (Triticum aestivum L.) in Central Saudi Arabia (AlGassim region) were surveyed in 1984 and 1985. Over 95% of the wheat fields were planted to the Yecora Rojo cultivar. Root and crown rots (Fusarium spp. and Helminthosporium spp.); brown root rot (Pythium spp.); leaf and head blotches (Helminthosporium spp.) and take-all (Gaeumannomyces sp.) were the most serious fungal diseases observed in the fields. Several H. sativum isolates were pathogenic to seedling leaves of most or all local and imported wheat cultivars (22 cultivars). Numerous soil-borne fungi were isolated from wheat roots and tested for pathogenicity to Yecora Rojo seedlings in the greenhouse. Alternaria sp., Helminthosporium spp. (two isolates), Fusarium spp. (three isolates), Pythium spp., Stemphylium spp. (two isolates) and Gaeumannomyces sp. were pathogenic to the inoculated wheat plants in the greenhouse.  相似文献   

9.
《Crop Protection》1988,7(5):303-308
Herbicides were sprayed in spring cereals with conventional and low pressure hydraulic flat-fan spray nozzles and rotary atomizers. The biological effects were measured on weeds and oats. In addition, some spray retention studies were performed. Conventional flat-fan spray nozzles at a spraying pressure of 2 or 4 bar (200 or 400 kPa) gave the best effect. There was no difference in effect between spray volumes of 125 1/ha and 250 1/ha. In most field situations, 200 kPa and 125 1/ha should be preferred. However, when the spray volume is reduced from 250 to 125 1/ha, the droplet size decreases and the drift hazard increases. Where great care has to be taken, the use of conventional flat-fan spray or low-pressure nozzles at 100 kPa and 250 1/ha may be a compromise between effect and safety.  相似文献   

10.
Protein content and protein yield of three spring wheat cultivars differing in morphological and physiological growth characters were found to be influenced by intercultivar competition, irrigation levels and nitrogen fertilization. The protein content of the tall cultivar C 306 and the protein yield of the dwarf cultivar HD 2160 were more than the other cultivars. Binary mixed stands were not superior to the better component cultivar. Intercultivar competition increased the protein content of dwarf and semi-dwarf cultivars, but decreased the protein content of tall cultivar. On the other hand, protein yield of the dwarf cultivar decreased and that of tall cultivar increased when grown in mixed stands. Protein yield of semi-dwarf cultivar increased when grown with dwarf cultivar, but decreased when grown with tall cultivar. Two or three irrigations increased the protein content and protein yield of all the three cultivars and their mixed stands over one irrigation. Protein content and protein yield of the cultivars and their mixed stands were higher when 150 kg N/ha was applied than when 80 kg N/ha was applied.  相似文献   

11.
Field experiments were conducted during the rainy seasons of 2009 and 2010 for the management of the major diseases of mungbean, namely, wet root rot (Rhizoctonia solani), cercospora leaf spots (Cercospora canescens and Pseudocercospora cruenta) and yellow mosaic (Mungbean Yellow Mosaic Virus) by using different combinations of an insecticide, fungicide, and bio-formulation as seed treatment, with or without foliar sprays. A combination of seed treatment with thiamethoxam (Cruiser™) at 4 g kg−1, carboxin (Vitavax™) at 2 g kg−1 and Pusa 5SD (Trichoderma virens) at 4 g kg−1 followed by simultaneous foliar sprays of thiamethoxam (Actara™) 0.02% and carbendazim (Bavistin™) 0.05% at 21 and 35 days after sowing resulted in the highest seed germination and grain yield in mungbean with the lowest intensities of cercospora leaf spots and mungbean yellow mosaic, and moderate incidence of wet root rot. The lowest whitefly population was also observed in this treatment during all stages of the crop. The treatment combinations having Pusa 5SD as seed treatment provided the lowest wet root rot incidence. Two sprays were superior to single spray for all variables recorded, but in combination with seed treatment, single spray was found to be more cost effective as it obtained the highest return per rupee of input. Use of T. virens based bio-formulation Pusa 5SD with insecticide thiamethoxam has been effectively demonstrated for the first time along with fungicides Bavistin and Vitavax for the management of the major diseases of mungbean.  相似文献   

12.
Three cultivars (two diploid and one tetraploid) in each of three maturity groups (early, intermediate and late) of perennial ryegrass were sown in 10 m2 plots, replicated four times, in Northern Ireland in June 1997 in a study of the effect of heading date on tiller development (including initiation to flower) and turnover of tillers produced at specific times in spring in 1998 and 1999. The plots were harvested seven times in each year. Annual dry‐matter production was similar for all groups in each year. In spring and early summer of both years, tiller density of the diploid cultivars was 1·5 times greater than that of the tetraploid cultivars and the mean tiller density over all swards in June was about 0·40 times greater than that in April. Maximum proportions of reproductive tillers in the early, intermediate and late maturity groups, determined from apical dissections, were found in early April, mid‐May and early June, respectively. Although a high proportion of tillers, which were present when annual observations commenced in spring, was decapitated at the first harvest in the early group, the previous population density was maintained by rapid production of new tillers during May, including those from suppressed tiller buds during reproduction. It is concluded that the relationship between heading date and rate of tiller turnover (including flowering) at specified times in spring is important in sward management throughout the early part of the growing season and should be taken into account in tiller‐based grass growth models.  相似文献   

13.
对‘中白1号’白化茶品种和‘茂绿’、‘中茶108’、‘春雨1号’、‘杭茶21’、‘鸠坑早’新品种(品系)等10个品种(品系)制得千岛银珍茶的感官品质、理化成分和杯泡观赏性等进行比较分析。结果表明,‘中白1号’、‘茂绿’和‘浙农117’品种制得的茶样感官品质明显好于对照‘鸠坑群体种’,特别是‘中白1号’白化茶品种,其高氨基酸低茶多酚的理化基础能明显改善芽茶滋味浓涩的品质缺陷。‘春雨1号’等芽头肥壮、厚实、圆直的品种茶样的杯泡观赏性较好,而芽头宽扁、松空的品种茶样杯泡观赏性较差。  相似文献   

14.
Four fungicides for seed treatments and one as foliar spray were tested in replicated field experiments in a strip plot design to determine the effect of fungicides on Helminthosporium leaf blight (caused by Cochliobolus sativus and Pyrenophora tritici-repentis) severity and grain yield of wheat. Wheat seed cv. RR 21 was treated with fungicides, carbendazim (Areestin), triadimenol (Baytan), tebuconazole (Raxil), and carboxin + thiram (Vitavax 200B). Single foliar application of propiconazole (Tilt) was sprayed at flowering stage. Controls were included for both factors and treatments were replicated four times. Triadimenol and carboxin + thiram increased seed germination in both years. Triadimenol, tebuconazole, and carboxin + thiram reduced the number of infected seedlings and seedling root rot severity in both years. Number of tillers was higher in carboxin + thiram treated plots compared to other seed treatments. Compared to the control, carboxin + thiram increased grain yield by 9% and 8% in 2004 and 2005, respectively, and triadimenol by 6% in both years. The foliar spray of propiconazole significantly reduced Helminthosporium leaf blight severity and increased thousand-kernel weights. Propiconazole spray increased grain yield by 15% and 14% in 2004 and 2005, respectively. Therefore, seed treatment either with triadimenol or carboxin + thiram in combination with single post-flowering foliar spray of fungicides should minimize grain yield loss due to wheat foliar blight in South Asia. The findings of this study could be useful in developing strategies to manage Helminthosporium leaf blight in South Asia and other warm wheat growing regions of the world.  相似文献   

15.
1998-2002年紫牡丹,金牡丹和黄玫瑰在武夷山与永春区试与示范鉴定结果表明:(1)产量高,比对照种福建水仙,黄旦,肉桂增产5.5%-44.3%,增产明显或显著;(2)品质优异,乌龙茶品质审评结果均明显超过福建水仙,亦优于肉桂和黄旦;(3)制优率高,超过福建水仙和肉桂;(4)种植成活率高,抗寒,抗旱性强,适应性广;(5)开采期早,金牡丹,黄玫瑰属早生种,紫牡丹亦比福建水仙,肉桂早,属中生种;(6)适宜在我省乌龙茶茶区大面积推广种植。  相似文献   

16.
Tetrahymena pyriformis was used to compare the relative nutritive value (RNV) of various components of wheat and rye bread. Rye bread crumbs were superior to those of wheat crumbs. The crust of both breads had considerably reduced RNV. When applied as an intervarietal screening tool in barley, this organism failed to detect small differences in the lysine content. Gross differences among various cereals and legumes could be detected. A colorimetric method for biomass measurement was compared with the direct microscope counting and found to be superior. The merits and limitations ofT. pyriformis as a test organism in the RNV determination are discussed.  相似文献   

17.
喷施硒对大豆品质和大豆食品硒水平的影响   总被引:23,自引:0,他引:23  
用田间试验研究喷施亚硒酸钠对大豆品质和大豆食品硒水平的影响。结果表明,叶面喷施亚硒酸钠浓度小于400mg/L对产量无显著影响,亚硒酸的浓度大于600mg/L,大豆产量显著下降。喷施亚硒酸钠显著提高大豆脂肪含量,特别是亚油酸含量提高1%左右,但对大豆蛋白质含量和氨基酸组成影响不显著。利用富硒大豆生产的大豆食品含硒量显著提高,大豆分离蛋白含硒量为7.487μg/g,豆奶粉为1.023μg/g,豆芽为1.033μg/g,白豆腐干为1.412μg/g.大豆分离蛋白可作为富硒功能食品的有机硒源,豆渣可作为动物饲料添加剂。  相似文献   

18.
High-temperature stress during the grain-filling stage reduces grain quality of rice, and this is a serious problem in Japan, especially in the Kyushu region. To solve this problem, various heat-tolerant cultivars have been bred, such as ‘Nikomaru’, ‘Kumasannochikara’, ‘Genkitsukushi’, ‘Sagabiyori’, and ‘Otentosodachi’. When cultivated under high temperature after flowering, these heat-tolerant cultivars had lower percentages of chalky grains than in the heat-sensitive cultivar ‘Hinohikari’. All the heat-tolerant cultivars markedly decreased the nonstructural carbohydrate content in the stem under the high temperature compared to control condition during early grain-filling stage, which is considered to be a common trait of heat tolerance. Notably, ‘Sagabiyori’, ‘Genkitsukushi’, and ‘Nikomaru’ maintained a nucellar epidermis at 17 days after flowering (DAF) under high temperature, whereas the nucellar epidermis disappeared in ‘Hinohikari’. In addition, the expression of AGPS2b, thought to be a rate-limiting enzyme in starch synthesis, in ‘Kumasannochikara’, ‘Otentosodachi’, and ‘Nikomaru’ did not decrease under high temperature, whereas ‘Hinohikari’, ‘Sagabiyori’, and ‘Genkitsukushi’ could not maintain expression of the gene at 17 DAF. Moreover, the expression of Amy3E, a starch-degradation-related gene considered to induce grain chalkiness, in ‘Kumasannochikara’ at 17 DAF was not increased by high temperature. These results suggest that the heat-stress-tolerant cultivars have various mechanisms for dealing with high-temperature stress.  相似文献   

19.
春季茶园虫、病、草无公害防治技术   总被引:2,自引:2,他引:0  
张觉晚 《茶叶通讯》2006,33(1):25-27
1春季茶园虫、病、草发生特点 (1)生长发育期长,各虫态较整齐,是一年防治的有利时期。  相似文献   

20.
Late spring cold(LSC) occurred in the reproductive period of wheat impairs spike and floret differentiation during the reproductive period, when young spikelets are very cold-sensitive. However, under LSC,the responses of wheat spikelets at various positions, leaves, and stems and the interactions between them at physiological levels remain unclear. In the present study, two-year treatments at terminal spikelet stage under two temperatures(2 C,-2 C) and durations(1, 2, and 3 days) were imposed i...  相似文献   

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