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1.
白花曼陀罗叶提取物对南方根结线虫生长发育的影响   总被引：5，自引：0，他引：5  
研究了白花曼陀罗(D a tura m etel L inn.)叶提取物对南方根结线虫(M eloid ogyne incogn ita Ch it-w ood.)生长发育的影响。结果表明,白花曼陀罗叶提取物对南方根结线虫胚胎发育和胚后发育有抑制作用。1%白花曼陀罗叶提取物处理48 h,仅有19.88%的卵完成胚胎发育,且变异卵增多;胚后发育历程、初侵染、初产卵日分别推迟2、4、6 d,雌虫产卵量降低。  相似文献   

2.
Guava is an important fruit species but poorly studied for the effect of humic substances and soil mulching on its nutrition and fruit production. Thus, an experiment was conducted to evaluate the nutritional status and fruit production of guava as a function of humic substances and soil mulching in Brazilian semiarid. The experimental design was in randomized blocks with treatments distributed in a factorial arrangement (5?×?2) referring to humic substances doses (0, 10, 20, 30 and 40?mL of Humitec plant?1) and organic mulching (with and without organic mulching). Nutritional status of guava is affected by humic substances and soil mulching. The use of humic substances combined with soil mulching promotes optimum supplies of nitrogen, phosphorus, calcium, sulfur, boron and iron, but not calcium, copper and zinc. Under sandy soil and semiarid climate it is possible to recommend 40?mL?L?1 of humic substances and soil mulching.  相似文献   

3.
ABSTRACT

A pot experiment was carried out to investigate the tolerance of cucumber plants (Cucumis sativus L.) to root-knot nematode after inoculation with Glomus intraradices. Plants were inoculated with G. intraradices for four weeks and then transplanted in soil treated with Meloidogyne incognita for a further five weeks. The low phosphorus (P) loamy soil was amended with 50 and 100 mg P kg?1 soil. Mycorrhizal colonization increased shoot dry weight, shoot length, leaf numbers, root fresh weight and shoot P concentration, whereas nematode penetration and reproduction were significantly decreased. Similarly, P fertilization usually increased shoot growth and significantly decreased the number of galls and the number of egg masses and eggs per g root. Our results indicate that inoculation with G. intraradices and P fertilizer confer tolerance of cucumber plants to M. incognita by enhancing plant growth and by suppressing reproduction and/or galling of nematodes during the early stages of plant growth.  相似文献   

4.
Abstract

A field experiment was conducted at Al Malak Valley Farm, El-Sharkeya Governorate-Egypt (30°–51° N; 32°–53° E) using 15 years old productive mango (Mangifera indica L.) trees cv. Zebda. The experiment was repeated for two successive seasons (2014/2015) and (2015/2016). The trees were planted 8×8 meters apart in sandy soil under drip irrigation system using the Nile water. Treatments included three concentrations of boron (0.0, 250, 500?mg L?1) and three concentrations of nitrogen (1000, 1250, 1500?g nitrogen/tree/year). Boron was applied as foliar spray of boric acid and nitrogen was applied to the soil as ammonium sulfate. Treatments were arranged in a factorial Completely Randomized Block Design with three replicates for each treatment. Results show that boron application has improved mango tree nutritional status. Leaf nitrogen, phosphorus, potassium and boron concentrations significantly increased as the boron application rate increased. In addition, boron application resulted in significant increase in leaf total chlorophyll, total carbohydrates, total sugars, carbon/nitrogen (C/N) ratio and decrease in total phenol content. Boron showed higher impact than nitrogen on all tested parameters. The interaction treatment of 250?mg L?1 boron and 1500?g/tree nitrogen proved to be the best treatment.  相似文献   

5.
Abstract

Zinc (Zn) as a microelement plays a salient role in the vital processes of plants such as metabolism and nutrition. This experimental study was conducted in the research field of Agriculture Faculty, Zanjan University using two genotypes of canola as main factor (Okapi and Tassilo) and zinc fertilizer application method in 7 levels including control, foliar spraying (2, 3.5, and 5?g/L) at the beginning of flowering and soil application (25, 50, and 75?kg/ha) were considered as sub-plot factor. The results showed that the application of zinc significantly increased the chlorophyll content as compared to control treatment. The highest chlorophyll content was observed in foliar spraying of 3.5 and 5?g/L zinc in Okapi cultivar. While, the highest value of RWC content resulted only with spraying 5?g/L of zinc. The result showed that zinc foliar of 5?g/L obtained the highest oil and seed yields and seed yield components. In addition, the highest qualitative seed traits (oil and protein content and zinc content in seed and plant) resulted with spraying 5?g/L of zinc. Also, Okapi cultivar had more quantitative and qualitative yields than Tassilo cultivar. The foliar spray of 5?g/L Zn can be recommended to increase the quantity and quality seed yield of canola.  相似文献   

6.
The effect of waterborne zinc on survival, growth, and feed intake of Indian major carp, Cirrhinus mrigala (Hamilton), advanced fry was studied under laboratory condition. Survival rates of C. mrigala advanced fry (2.71?±?0.49 g) after 30 days exposure to control (0.01), 0.03, 0.06, 0.10, and 0.15 mg/L zinc using the static renewal method in freshwater at pH 7.3?±?0.2, temperature 26?±?2°C, and total hardness 114?±?16 mg/L as CaCO3 were 100%. Growth of the fish exposed to 0.10 and 0.15 mg/L of zinc was significantly lower (P?<?0.05) than in control (0.01), 0.03, and 0.06 mg/L of zinc after 30 days of exposure. However, there were no significant differences (P?>?0.05) in fish growth between 0.03 and 0.06 mg/L zinc concentrations. Feed intake rates were significantly (P?<?0.05) reduced in the fish exposed to 0.10 mg/L and higher levels of zinc. The zinc accumulation in the whole body of the fish increased with increasing concentrations of the metal.  相似文献   

7.
Abstract

This investigation was conducted during two successive seasons (2014/2015) and (2015/2016) using 15?years old productive mango (Mangifera indica) trees cv. Zebda. The trees were grown at AlMalak Valley Farm, El-Sharkeya Governorate- Egypt (30–51° North; 32–53° East). Trees were planted 8?×?8 meter within and between rows in sandy soil under drip irrigation system using the Nile water. The objective of this study is to alleviate alternate bearing in cv. Zebda using mineral nutrients (nitrogen in the on year and boron in the off year). Treatments included three concentrations of nitrogen (1000, 1250, 1500?g/tree/year) and three concentrations of boron (0.0, 250, 500?mg L?1). Nitrogen was applied to the soil as ammonium sulfate and boron was applied as foliar spray of boric acid. The extra amount of nitrogen fertilizer (250 and 500?g N/tree) was applied at three installments in (May, June and July). Treatment was arranged in a factorial Completely Randomized Block Design with three replicates for each treatment. Results show that the on-year nitrogen fertilization significantly increased mango tree vegetative growth (number of shoot/branch, shoot length, shoot thickness, number of leaves/meter and leaf area) and yield. The average yield in the on year is 85.5?kg/tree at 1250?g N/tree but 67.4?Kilogram/tree at 1000?g N/tree (the control treatment). While in the off year boron foliar application resulted in a significant increase in flowering, initial fruit set, final fruit set and fruit yield. The average yield in the off year is 47?kg/tree at 250?mg L?1 boron but 9?kg/tree at 0.0?mg L?1 boron rate (the control treatment).The interaction treatment of 250?mg L?1 boron + 1500?g nitrogen/tree is the best treatment as it resulted in the highest values for all the tested parameters. The average yield of this treatment is 53.5?kg/tree. This treatment helps alleviate alternate bearing phenomenon by 41% and obtain the highest economic yield in the off-year, i.e. increased yield by 5.9 fold.  相似文献   

8.
Abstract

The objective of this study was to evaluate the effects of cobalt (Co) and molybdenum (Mo) doses in the treatment of seeds on the biosynthesis of nitrogen compounds, photosynthetic pigments, sugars, and production of peanut plants. The doses of Co and Mo used were 0, 2, 3, and 4?mL kg?1 seed, which were applied immediately before sowing. Seeds treated with Co and Mo at a dose of 4?mL kg?1 yielded peanut plants with higher concentrations of photosynthetic pigments, carotenoids, and sucrose in leaves. Application of Co and Mo doses also increased biological nitrogen fixation by increasing the concentration of allantoic acid, nitrate, ammonia, and amino acids in leaves. The concentration of total amino acids corresponded to most of the nitrogen compounds (on average 50%), followed by the concentrations of nitrate (35%), ammonia (11%), allantoic acid (7%), and allantoin (0.2%). Application of 4?mL kg?1 increased the production of total amino acids compared with the control treatment. Pod yield was not affected by the Co and Mo doses; however, treatment of peanut seeds with 4?mL kg?1 was the most viable alternative for increased production of primary metabolism compounds, nitrogen forms, and photosynthetic pigments in peanut plants. This study provides important information regarding the role of Co and Mo in the biological nitrogen fixation of peanut plants. Future experiments should be conducted using a dose of 4?mL kg?1 with different genotypes to verify the potential for increasing peanut yield.  相似文献   

9.
The filamentous fungi Trichoderma spp. is currently developed as biocontrol agents against many plant pathogens. Recent studies have shown that these fungi are able to infect nematode eggs and juveniles. In this research, biological control of root-knot nematode (Meloidogyne javanica) by Trichoderma harzianum BI was investigated in greenhouse and laboratory experiments. Results showed that different concentrations (102–108 spores/ml) of T. harzianum BI decreased nematode infection and other parameters significantly, compared to control. T. harzianum BI was able to penetrate nematode egg mass matrix and significantly decreased nematode egg hatching level. Specific activities of resistance-related enzymes, namely peroxidase (POX), polyphenol oxidase (PPO) and phenylalanine ammonia lyase (PAL) increased significantly in T. harzianum BI inoculated plants. Maximum activities of POX, PPO and PAL were observed at the 5, 5 and 6 days after inoculation, respectively. Chitinase activity was also increased in culture filtrates of T. harzianum BI grown on wheat bran moistened with salt solution supplemented with colloidal chitin or nematode eggs. Maximum activity of chitinase was recorded at the 4 days after inoculation, in media supplemented with colloidal chitin (1.15 U/min per ml) and nematode eggs (0.85 U/min per ml). Results suggested that direct parasitism of eggs through the increase in extracellular chitinase activity, which would be indicator of eggs infection capability, and inducing plant defense mechanisms leading to systemic resistance are two main suppression mechanisms used by T. harzianum BI against nematode.  相似文献   

10.
ABSTRACT

A pot experiment was conducted in a greenhouse on a calcareous soil (fine, mixed, mesic, Fluventic Haploxerepts) to study the interaction of zinc (Zn) and boron (B) on the growth and nutrient concentration of corn (Zea mays L.). Treatments consisted of a factorial arrangement of seven levels of B (0, 2.5, 5, 10, 20, 40, and 80 mg kg? 1as boric acid), two sources of Zn [zinc sulfate (ZnSO4 · 7H2O) and zinc oxide (ZnO)], and three levels of Zn (0, 5, and 10 mg kg? 1) in a completely randomized design with three replications. Plants were grown for 70 d in 1.6 L plastic containers. Applied Zn significantly increased plant height and dry matter yield (DMY) of corn. Source of Zn did not significantly affect growth or nutrient concentration. High levels of B decreased plant height and DMY. There was a significant B × Zn interaction on plant growth and tissue nutrient concentration which were rate dependent. In general, the effect of B × Zn interaction was antagonistic on nutrient concentration and synergistic on growth. It is recommended that the plants be supplied with adequate Zn when corn is grown in high B soils, especially when availability of Zn is low.  相似文献   

11.
Degradation factors can cause both quantitative and qualitative changes in fauna and thus affect soil functioning. The use of bio-indicators may help to detect environmental changes. The aim of this study was to evaluate the effects of lead and cadmium on the biology (mortality, reproduction, egg hatching) of two euedaphic collembolans, Sinella coeca and Folsomia candida and to evaluate sensitivity differences between the two species. The results showed that low concentrations of lead did not cause dramatic effects on the survival and reproduction of both species. Reproduction of both species was reduced when the soil contained a nominal concentration of Pb at 1000 μg g–1. S. coeca and F. candida showed a high sensitivity to cadmium and both their reproduction and survival were significantly reduced on exposure to 50 μg g–1. Moreover, egg hatching of F. candida was affected by the cadmium concentrations in the soil, and by the amount of time that the eggs stayed in contact with cadmium. This study showed that the inhibition determined by Cd on F. candida juvenile production was caused in part by inhibition of deposition and, in part, by reduction of egg viability.  相似文献   

12.
不同硼效率甘蓝型油菜品种中硼的形态及其相互关系   总被引：12，自引：5，他引：12  
采用硼高效 (9589,9590)和硼低效 (9141,95105)甘蓝型油菜品种各 2个及其 4个杂交种 (95105 9589,95105 9590 ,91419589,9141 9590)作试材 ,研究了不同硼效率甘蓝型油菜品种及其F1代花期各部分叶片中硼的形态。结果表明 ,在B2 (0 .35mg/kg)处理下 ,硼高效品种上叶 ,中叶 ,下叶和花中水溶态硼含量和束缚态硼含量低 ,半束缚态硼含量高 ,而硼低效品种 3种硼形态的含量则与此相反 ;F1代基本居于二者之间 ,且趋向于高效品种 ;在B1(0 .2 0mg/kg)处理下 ,各叶片和花中各硼形态含量也呈现类似的特征 ,但存在例外 ,尤其在花中。B1和B2处理下 ,除B1处理上叶外 ,硼高效品种和F1代的花和叶片中水溶态硼和束缚态硼相对含量较低 ,半束缚态硼相对含量较高 ,硼低效品种与此相反。建立了硼形态之间的相互平衡关系 ,并把这种平衡关系同硼效率联系起来 ,表明硼形态和硼效率存在密切关系 ,可望由此揭示不同甘蓝型油菜品种硼效率差异的生理机制。  相似文献   

13.
Foliar fertilization may be a viable strategy to boron supply in irrigated cropping systems with common beans (Phaseolus vulgaris), since it prevent B leaching. The aim of this work was to evaluate the economic viability and physiological parameters of the common beans production in irrigated cropping systems using sources and increasing foliar boron doses. A field experiment was carried out using an experimental block design in a factorial scheme 2?×?5?×?3, with two sources of B (boric acid and borax) and five doses: 0 (control), 2, 4, 6 e 8?kg?ha?1, with three repetitions. Foliar B applications were performed at 40 days after seeds germination, in pre-flowering stage. Physiological process (transpiration, stomatal conductance, CO2 internal concentration, net photosynthesis, and relative chlorophyll index), B level in leaves and grain yield were measured. These data were used to determine the economic viability of B fertilization in common beans. Both boric acid and borax increased B levels in common beans leaves. Borax affected some physiological process reducing stomatal conductance and increasing net photosynthesis. Using borax, the highest net photosynthesis was observed at a rate of 4?kg?ha?1, while the boric acid increased net photosynthesis linearly after increasing B doses application. An enhance of 311?kg?ha?1 in the grain yield was observed using borax related to the control (without B application); however, grain yield decreased linearly after application of increasing B doses, as boric acid. Comparing the economic viability of sources and doses of B, the highest profitability is obtained using borax at a rate of 4?kg?ha?1, which promoting a differential profit of US$534.44 per hectare compared to common beans cropping without B.  相似文献   

14.
A sensitive measure of growth in the duckweed, Lernna minor, was used to demonstrate the tolerance of this higher plant to boron [B(OH)3] at levels of 10 to 20 μg/mL in the growth medium at pH 5.0. Growth inhibition by B in concentrations up to 100 μg/mL in the external medium was reversible after transfer to control medium. At pH 4.0 and in the presence of 20 μg/mL B for 7 days, the plants accumulated 93 μg B/g fresh weight (148% of the control) and this increased with pH up to pH 7.0 where the plants accumulated 257 μg B/g fresh weight (525% of the control). Only at pH 7.0 in the presence of B was growth inhibited. Thus, plants which had accumulated more than 100 μg B/g fresh weight still grew normally. This corresponds to about 800 μg B/g dry weight accumulated by this monocot without effect upon growth rate.  相似文献   

15.
The potential effect of rhizobial inoculation on root knot nematodes in chickpea, mungbean and pigeonpea were studied under field condition. The seed treatment with respective rhizobium strains increased the nodulation, leghemoglobin content, bacteriod population, plant growth, yield and nitrogen uptake of three three food legumes compared to the plants without the rhizobium treatment. The nematode (1500?juveniles/kg soil) incited oval galls on the roots of the three legumes, and suppressed plant growth and yield. The galling, egg mass production and soil population of the nematode was greater on the plants without the rhizobium treatment. The pure culture and culture filtrate of the rhizobium strains suppressed the egg hatching and induced mortality to the juveniles of M. incognita over control. The nematode infection reduced the nodulation, bacteroid population and leghemoglobin contents of the nodules and NPK uptake by the plants. Hence, the rhizobia treatment shall be integrated to common agronomic practice of food legume cultivation so as to enhance crop productivity and to protect roots from nematode attack.  相似文献   

16.
The release of active ingredient chemicals in conventional organic amendments is primarily through microbial degradation, whereas in granular phytonematicides, leaching through irrigation water had been implied as a probable mechanism. The objective of this study was to determine the role of effective microorganisms (EM) on the efficacy of Nemarioc-AG (NAG; G?=?granular formulation) phytonematicide on suppression of root-knot (Meloidogyne species) nematodes and growth of tomato (Solanum lycopersicum) plants. A 5?×?6 factorial experiment, with EM at 0%, 0.14%, 0.17%, 0.20% and 0.25% and phytonematicide at 0, 3, 6, 9, 12 and 15?g per plant, was conducted under microplot conditions. Each plant was inoculated with 11,000 eggs and second-stage juveniles (J2) of Meloidogyne incognita. Seventy days after initiating the treatments, the interactions were not significant (P?≥?.05) on all variables, but the main factors were highly significant. Regression of nematode population densities, root gall and dry shoot mass over increasing phytonematicide concentration exhibited quadratic relations, which were explained by 93%, 97% and 99%, respectively. In contrast, stem diameter and phytonematicide concentration had a positive linear relation, which was explained by 98%. Nematode numbers over increasing EM concentration exhibited quadratic relation, which was explained by 97%. All plant variables and EM had no significant relations. In conclusion, the efficacy of NAG phytonematicide on nematode suppression and plant growth was independent of EM activities, suggesting that irrigation water played a major role in the efficacy of the product in granular formulation.  相似文献   

17.
采用溶液培养试验,研究了缺硼对两种不同砧木纽荷尔脐橙硼、锌、钙、镁和钾元素含量变化。结果表明,缺硼显著降低了枳壳砧木纽荷尔脐橙体内硼含量而对锌含量影响不大; 相反,缺硼对枳橙砧木脐橙体内硼含量的影响不是很大,而显著降低了其叶片中锌的含量。这可能是缺硼条件下枳壳砧木脐橙容易出现缺硼症状,而枳橙砧木脐橙容易出现缺锌症状的原因之一。与对照相比,缺硼处理的枳壳砧木脐橙叶的钙含量明显增加; 而根的钾含量明显高于枳橙砧木橙根。这些结果与枳壳砧木脐橙对硼更敏感有一定的关系。缺硼对镁含量的影响两种砧木间基本没有差异。  相似文献   

18.
Pratylenchus brachyurus is one of the main limiting factors of agricultural yield in annual crops, particularly due its difficult management. Methods to reduce populations are constantly sought, and the use of resistance inducers deserves attention. Thus, the study aimed to assess the effect of acibenzolar-S-methyl (ASM) application in different doses to P. brachyurus control in maize. Initially, 1000 specimens of P. brachyurus were inoculated in maize for the multiplication. After 60 days, the aerial part (AP) was discarded and maize was sown under the treatments: seed treatment (ST), application in the AP and ST?+?AP, in the doses of 0.125, 0.25, 0.5 and 1.0?g i.a./L. Vegetative and nematological parameters were assessed 60 days later. ASM did not affect plant growth, but reduced nematode population in all the treatments. The treatment methods did not differ and reduced the number of nematodes/g root by 64.25 to 80.14% compared to the control. The doses of 0.6, 0.51 and 0.65?g i.a./L promoted the most reductions in the number of nematodes/g root when applied in ST, AP and ST?+?AP, respectively. Thus, we recommend the use of ASM applied on shoot in a dose of 0.50?g i.a./L.  相似文献   

19.
Abstract

In the last decades, soybean (Glycine max (L.) Merrill) was the crop with the highest acreage in Brazil. Soybean has been cropped under unfertile soils as sandy soils and those under pasture decaying where applying high fertilizer levels have significant responses. The presence of calcium (Ca) and magnesium (Mg) concentration in the upper layers promotes ions imbalanced concentration in soil solution because the soil acidity correction reduces the uptake of other cations as zinc (Zn). The objective of this study was to evaluate under nutritive solution conditions, the Mg influence in Zn distribution and mobilization into plants from four soybean cultivars with different nutritional requirements. The experimental design was complete randomized blocks in factorial scheme 4?×?2?×?4 being with four soybean cultivars (FT Estrela, DM Nobre, IAC 17, and IAC 15-1), two Mg rates (0.1 and 1.0?mmol?L?1), four Zn rates (0, 1, 2, and 5?µmol?L?1), and four replicates. The IAC 17 and FT Estrela cultivars with determinate growth and high nutritional requirements, and the IAC 15-1 and DM Nobre with tolerance to soils partially corrected, average fertility, or both were investigated. In the highest Mg rates, we verified increase in grain yield (GY) as well as in the Zn rates up to 2.0?µmol?L?1. The Mg?×?Zn interaction was significant and the IAC 17 cultivar was the most responsive to Zn under nutritive solution. The foliar nutrient concentration was significantly modified by Mg rates. The Mg at 1.0?mmol?L?1 presented the lowest nutrient concentration in soybean plants and increased the shoot dry weight yield (SDWY) in plant and grain no matter the nutritional requirement from every cultivar.  相似文献   

20.
The beneficial effect of corn seed treatment with zinc (Zn) is directly related to the source used. The excess of this micronutrient causes seedling stress and reduces growth. Thus, assuming that the use of exogenous phytohormones can minimize such effects, we evaluated different doses and sources of Zn for the treatment of maize seeds with or without salicylic acid. The experiment took place in the laboratory, and two factorial experiments, 2 × 4 + 1, were performed in a randomized design. The seeds were treated with either ZnO or ZnSO4 at doses of 0.5, 1, 2, and 3 g.kg?1 seed with four replications, differing only by the addition of 4.14 mg L?1 salicylic acid. Treating seeds with Zn and salicylic acid did not affect germination. ZnO led to a greater increase in dry mass in corn seedlings as compared with zinc sulfate, especially at higher doses (2 and 3 g kg?1 seed). Seed treatment with sulfate reduces root and shoot length, and salicylic acid did not attenuate this toxic effect. Dry mass is not affected when oxide is used. Salicylic acid reduces the accumulation of zinc in the treatment of corn seeds, regardless of the source used.  相似文献   

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