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1.
ABSTRACT

This study was conducted to determine the effects of nitrogen (N) doses on yield, quality, and nutrient content in broccoli heads. Treatments consisted of 0, 150, 300, 450, and 600 kg N ha? 1. Nitrogen rates significantly increased yield, average weight of main and secondary heads, and the diameter in broccoli compared to control. The highest total yield (34631 kg ha? 1) was obtained at 300 kg N ha? 1. At harvest, the highest amount of the total N in broccoli heads was measured at 450 kg N ha? 1 application. Potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), and zinc (Zn) content increased with increases in nitrogen treatments but, phosphorus (P), copper (Cu), manganese (Mn), boron (B), and sodium (Na) contents were not influenced. Also, removed nutrients by broccoli head were highest at 300 kg ha? 1N rate.  相似文献   

2.
耿明建  吴礼树  曹享云  刘武定 《土壤》2007,39(6):938-942
溶液培养条件下研究硼(B)对不同B效率棉花品种水溶性果胶、原果胶及水溶性B、酸溶性B含量的影响.结果表明,供B充足时,B低效棉花品种各部位果胶含量均大于高效品种,不同形态B含量也有同样的规律.缺B时,高效品种各部位果胶含量一般高于低效品种.严重缺B使2个棉花品种不同形态B含量均显著降低,水溶性B变化比酸溶性B更明显,低效品种各部位酸溶性B及上部幼叶水溶性B含量降低幅度均大于高效品种,下部老叶和根中水溶性B降低幅度小于高效品种.缺B还使2个品种上部幼叶与下部老叶水溶性B含量比值增加,高效品种增加幅度大于低效品种,该比值在品种间的差异明显大于水溶性B和酸溶性B含量的差异,可以更好地反映不同品种的B效率.  相似文献   

3.
水稻不同生育期对硒的吸收、转运及累积规律   总被引:1,自引:0,他引:1  
管文文  戴其根  张洪程  尹雪斌 《土壤》2018,50(6):1150-1154
采用大田试验,研究土壤施用含硒肥料后水稻中硒的积累和分布的动态变化。结果表明:在水稻不同器官中硒的积累量与含硒肥料施用量呈正相关,相关系数达到0.98以上。水稻成熟期,硒施用量30 kg/hm2和120 kg/hm2处理全株硒浓度分别比对照处理提高了98.9%和313.7%。不同生育期,水稻各个器官中硒含量及累积量不同,水稻硒的生物富集高峰期表现在孕穗期,叶与水稻穗部吸收累积硒有着密切关系。水稻成熟期整个植株中硒的累积量为茎叶精米根颖壳。在整个水稻生育期硒有一定的运转累积规律:水稻分蘖期时,硒从根、茎流向叶片;孕穗期再由叶流向茎;灌浆期又从根运转到叶和穗中;最后成熟期叶中的硒流向穗。苗期施用含硒肥料是一条提高水稻硒含量的有效农艺措施。  相似文献   

4.
沼泽土施硒对黑麦草生长、品质及生理活性的影响   总被引:4,自引:1,他引:4  
用土培试验方法研究了若尔盖高原沼泽土施硒对黑麦草(L.mu ltiflorum Lam aubada)生长、品质、谷胱甘肽过氧化物酶(GSH-Px)活性及根系活力的影响。结果表明,适量施硒能促进黑麦草的生物量、GSH-Px活性和根系活力的增加;当施硒高于20 mg kg-1时黑麦草的生长受到抑制,GSH-Px活性与根系活力均随之降低。施硒量在0~20 mg kg-1范围时,黑麦草的粗蛋白、粗脂肪、磷和钙的含量随施硒量的增加而提高,粗纤维与硅的含量下降。适量施硒能促进黑麦草的品质改善。  相似文献   

5.
北京市挂甲峪地区土壤全硒含量分布特征   总被引:1,自引:0,他引:1  
为调查北京市挂甲峪地区土壤全硒含量分布特征,探讨不同土地利用方式和海拔高度对土壤全硒含量的影响,采集挂甲峪地区表层土壤(0~20 cm)样品122个,采用GIS方法对土壤全硒含量进行了空间分布特征研究。结果表明:挂甲峪地区土壤全硒含量变幅为0. 06~0.76 mg/kg,平均值为0. 30 mg/kg。86.88%的土壤全硒含量处于足硒及以上水平( 0.175 mg/kg),其中有20.49%的土壤属于富硒含量(0.40~0.30 mg/kg)。不同土地利用类型间以草地土壤全硒含量平均值最高(0.40 mg/kg),其次是林地(0.37 mg/kg),最低为园地(0.25 mg/kg)。表层土壤全硒含量随海拔高度的增加呈上升趋势。土壤硒元素的块金值为0.0014,块金系数为88.10%,空间相关性弱。挂甲峪地区整体上呈北西向带状分布,存在富硒土壤。  相似文献   

6.
Abstract

In this study, the effects of boron (B) and calcium (Ca) supply on Ca fractionation in suspension cells and different tissues of rape (Brassica napus L.) plants of two cultivars with different B efficiency were studied, with a purpose to elucidate the mechanism by which B affects Ca concentration in plants. As Ca supply increased in nutrient solution or culture medium, the relatively easily extractable Ca fractions, that is H2O and 80% ethanol extractable Ca in leaves, 1 mol L?1 NaCl extractable Ca in upper leaves, roots and suspension‐cell were significantly increased. While the recalcitrant Ca fractions extracted by 2% acetic acid, 0.6 mol L?1 HCl and Ca in the residue were not affected by Ca supply. Increasing B supply in nutrient solution or culture media significantly reduced 1 mol L?1NaCl extracted Ca in suspension cell and roots of both cultivars, which were most likely related to the alteration of cell wall metabolism. Calcium extracted by 2% acetic acid, 0.6 mol L?1 HCl and Ca in residue in suspension‐cell and roots of B inefficient cultivar Bakow were easily improved by B deficiency as compared to that of B efficient cultivar Tezao16. Increasing of these relative recalcitrant Ca fractions was related to the different response of cultivars to the B deficiency, which may reflected different extent that Ca deposited in the two cultivars due to impaired membrane integrity under B deficiency. The effects of B on Ca concentration in lower and upper leaves of the two cultivars were quite different and were the integrated effects of B on Ca metabolism, Ca transport in plants and growth of certain organ. Increasing B supply increased total Ca concentration in upper leaves of Bakow and reduced that of Tezao16, which might relate to the different adaptability of the two cultivars to comparatively higher B supply.  相似文献   

7.
西兰花属于呼吸跃变型花菜类蔬菜,采后极易黄化、失水萎蔫,采后流通过程中保鲜技术对西兰花产业的持续发展尤为重要,而预冷技术是果蔬冷链物流的首要环节,对整个冷链过程中蔬菜的保鲜效果有着很大的影响,为给不同预冷技术在西兰花产业中的应用提供参考。通过引据国内外相关文献,总结归纳了不同预冷技术处理后西兰花的生理变化规律,对比分析了各预冷技术的优缺点,系统阐述了不同预冷技术对西兰花货架期、呼吸代谢及营养品质的影响和调控机理。从学者的大量研究成果发现,各种预冷技术的优缺点已十分明确,水预冷、空气预冷和真空预冷等预冷方式都在一定程度上延长了西兰花的货架期。  相似文献   

8.
Abstract

Splitting of sweet potato tubers because of boron (B) deficiency is a major cause of reduction in marketable tuber yield in India. Soil and plant tests are employed in this study to determine the fertilizer B requirement (FBR). Fertilizer B requirement of sweet potatos grown on an Alfisols under rainfed conditions was evaluated by two simple methods. In the first method, the relationship between B uptake and sweet potato tuber yield was utilized to find the B uptake at a given sweet potato tuber yield. This relationship was then used to find the amount of B applied for that particular uptake to set the targeted yield. In the second method, FBR was determined using the equation: FBR=(UB?U0)/BRF, where UB is B uptake at a given yield, U0 is B uptake from unfertilized soil, and BRF is the recovery of applied B. All of these parameters were determined in a field experiment with sweet potatos grown on Alfisols under rainfed conditions. The results of the study indicated a very good relation between observed value of FBR and predicted values determined by both the methodologies. Results of the study suggest that the simple models developed based on B uptake can be utilized for determining the B requirements of sweet potato.  相似文献   

9.
Boron (B) toxicity might be a problem, especially in dry regions of the world, however; its distribution still largely unappreciated and ignored by soil and crop scientists. Therefore, this study aimed to assess B spatial distribution in an area of northern Nile Delta, the most fertile and populated area in Egypt. Soil B was extracted by Mehilch-3 extraction and measured by inductively coupled plasma spectrometry (ICP). The mean B concentration was recorded as 5.19, 6.04, and 6.41 ug/g in surface (S), subsurface (Ss), and lower (L) layers, respectively. . The data were interpolated in ArcGIS software. The highest B concentration was observed in the central part of this area, which may be attributed to many reasons such as pollution sources and management practices. Our results indicated that more than 50% of the studied area highly concentrated in B, which represents a threat to soil and ecosystems in North Nile Delta.  相似文献   

10.
硼对烟草生理特性及品质影响的研究进展   总被引:1,自引:0,他引:1  
硼是烟草生长过程中不可缺少的微量元素,参与烟草的生长发育和生理生化反应,并最终影响烟叶的品质和质量。本文综述了硼对烟草细胞组织结构、光合特性、酶活性、核酸和蛋白质及品质的影响,并从硼肥用量和硼肥利用率等方面进行了展望。  相似文献   

11.
The selenium contents of soil and its uptake by a wide variety of crops are analyzed along a transect, with the sampling stations located at Mawkyrwat, Upper Shillong, Pynthormukrah, and Nongpoh. Each site is successively farther away from uranium deposits, with the closest being Mawkyrwat (50 km). Leafy vegetables had greater selenium content than tubers and fruits. The concentrations of selenium in soil ranged from 70 μg g?1 to 296 μg g?1 and in vegetables varied from 26 μg g?1 to 225 μg g?1. Selenium is known to be a decay product of uranium, and the results indicate that the selenium content of soil and vegetables of Mawkrywat is greater than the other three sampling sites. This can be attributed to the proximity of this site to uranium deposits of Domiasat. The possible implications of selenium on human health are discussed.  相似文献   

12.
Nine stream sites in the Blackfoot River watershed in southeastern Idaho were sampled in September 2000 for water, surficial sediment, aquatic plants, aquatic invertebrates, and fish. Selenium was measured in these aquatic ecosystem components, and a hazard assessment was performed on the data. Water quality characteristics such as pH, hardness, and specific conductance were relatively uniform among the nine sites examined. Selenium was elevated in water, sediment, aquatic plants, aquatic invertebrates, and fish from several sites suggesting deposition in sediments and food web cycling through plants and invertebrates. Selenium was elevated to concentrations of concern in water at eight sites (>5 g/L), sediment at three sites (>2 g/g), aquatic plants at four sites (>4 g/g), aquatic invertebrates at five sites (>3 g/g), and fish at seven sites (>4 g/g in whole body). The hazard assessment of selenium in the aquatic environment suggested low hazard at Sheep Creek, moderate hazard at Trail Creek, upper Slug Creek, lower Slug Creek, and lower Blackfoot River, and high hazard at Angus Creek, upper East Mill Creek, lower East Mill Creek, and Dry Valley Creek. The results of this study are consistent with results of a previous investigation and indicate that selenium concentrations from the phosphate mining area of southeastern Idaho were sufficiently elevated in several ecosystem components to cause adverse effects to aquatic resources in the Blackfoot River watershed.  相似文献   

13.
Wide variations in boron (B) contents are typical of Turkish soils and plants, and most of the variation, 84% of the plant-soil B values are within the “normal.” Boron application on low B soils can make a contribution to yield in cotton and sunflower crops. Field experiments were carried out on clayey and medium-textured soils, which are Chromoxererts, Haploxererts, Xerochrepts, and Xerofluvents in Southern Turkey to study the effects of boron fertilization on irrigated cotton and rainfed sunflower growth, yield, and yield components. Four levels of boron—0, 1, 2, and 3 kg ha?1—were applied at planting and the experimental design was completely randomized block design with four replications. There was a 31% and 31.9% increase in seedcotton yield at 3 kg and 2 kg ha?1 of B, compared to the control only two out of four sites. There was an average increase of 61.4% in boll weight with 2 kg B ha?1 application compared to the control. Effect of different application rates of B was not significant for fiber length, fiber strength, and fiber length uniformity. All levels of boron produced higher head diameters over control only one out of four sites. Boron applied at the level of 3 kg ha?1 produced the highest 1000 seed weight of 47.5 g representing an 18% increase over the control. Boron applied at the level of 1 kg ha?1 produced the highest seed yield, representing a 25% increase over the control only at one out of four sites. Boron was no value as a fertilizer for sunflower under given experimental conditions even though some uptake of boron was occurred. Boron fertilization may be regarded as effective in improving cotton yields.  相似文献   

14.
Broccoli (Brassica oleracea L.var italica Plenck) is an important winter season exotic vegetable from the Brassicaceae family as well as heavy feeder of plant nutrients. Plant nutrition is one of the prime considerations for getting higher yield of any crop. Mineral fertilizer improves growth and yield of broccoli due to the role of nitrogen, phosphorus, and potassium on the meristematic activity. Boron and molybdenum are essential micronutrients required for normal plant growth and development. Plants differ widely in their requirements, but the ranges of deficiency and toxicity are narrow. Boron and molybdenum deficiencies are very common in Cole crops. Deficiency causes many anatomical, physiological, and biological changes. The deficiency of boron and molybdenum has threatened the ever increasing areas of broccoli. The effected heads become irregular in shape, smaller in size and bitter in taste which adversely affects the market demand of the crop. No systematic work so far has been done in production technology of sprouting broccoli in relation to response of nutrients in the gangetic plains of West Bengal. The present investigation was attempted to find out the growth, yield, and quality of broccoli on the aspects of minor mineral (boron and molybdenum) nutrition. The experiments were conducted at the Horticultural Research Station of Bidhan Chandra Krishi Viswavidyalaya, Mondouri, Nadia, West Bengal, during 2010–12 with four levels of boron (0, 15, 18, and 21 kg ha?1) and molybdenum (0, 1.2, 1.5, and 1.8 kg ha?1). Design of the experiment was a Factorial Randomized Block Design. Biometric observations were recorded from the selected plant from each plot and each replication of both the years. It was concluded from the results that under favorable agro-climatic conditions, the application of 18 kg borax and 1.8 kg ammonium molybdate ha?1 was found beneficial for growth, yield, and quality of broccoli.  相似文献   

15.
为进一步挖掘和发挥地区农业资源优势,推进高原夏菜和当归产业健康可持续发展,经过试验示范和生产实践,从范围、规范性引用文件、术语和定义、产地环境、西兰花栽培技术、绿肥复种技术、轮作当归栽培技术等方面制订了西兰花复种绿肥-当归高效轮作种植技术规程,以更好地指导生产。  相似文献   

16.
水稻不同生育期对硒吸收累积及铁膜的吸附特性   总被引:2,自引:0,他引:2  
采用盆栽试验方法,研究不同生育期水稻各部位对硒的吸收累积及根表铁膜对水稻吸收积累硒的影响机制。结果表明:水稻营养器官生物量在拔节期积累最快,不同时期营养器官中硒含量不同,根中的硒在拔节期达到最大,根和茎中的硒在灌浆期和成熟期被转运至其他部位。水稻各组织中约50%的硒在拔节期和孕穗期被吸收,小穗吸收总硒的47.22%且是在孕穗期完成的,说明这两个时期对于水稻硒吸收累积非常关键。铁膜中硒占总硒的比例在幼苗期高达73.63%,是同时期茎中硒所占比例的4.87倍。随着生育期的推进,铁膜中硒所占比例显著递减,在成熟期降低至20.02%,同时期茎中硒占总硒的比例为65.42%。这表明,根表铁膜在水稻整个生长周期内通过吸附作用使其表面能够富集一定量的硒,在水稻生育后期,当土壤溶液中硒含量较少时,根表铁膜可能会作为一个硒源,吸附在根表铁膜中的硒重新被水稻所利用,铁膜在水稻硒吸收转运的过程中扮演了"缓冲器"的角色。明确不同生育期根表铁膜对水稻硒累积特性,在生产管理中可在不同生育期采取措施提高稻田硒生物有效性,从而为进一步提高农产品中硒含量提供科学依据。  相似文献   

17.
塔克拉玛干沙漠不同立地条件下咸水滴溉苗木的生长差异   总被引:14,自引:1,他引:14  
为了开发利用塔克拉玛干沙漠地下高矿化度咸水进行沙漠公路绿化,2003年在肖塘进行了高矿化度地下咸水灌溉实验。实验点选择在流动沙丘和丘间平地上,按照荒漠林土覆沙厚度差异和坡向不同,选择了9种不同的立地条件的实验点。样地中栽植梭梭、柽柳、盐穗木等3种植物。实验结果如下:(1)立地条件对植物生长的影响主要是通过其对水分和太阳辐射的差异分布而引起的;(2)不同植物种对于高矿化度的咸水灌溉适应性不同,适应性因土壤母质条件的差异而变化;(3)植物生长的不同阶段,生长限制因子不同,在成活时期水分因子是其限制因子,而在生长时期中,在水分满足的条件下,地表太阳辐射能量是其限制因子。  相似文献   

18.
A field experiment was carried out at El-Khattara region (Sharkia Governorate, Egypt) during the 2009 season to study the effect of potassium (K) fertilization, gypsum addition rates, and foliar spraying with boron (B) and combinations of them on growth, yield, yield components, oil quality, and uptake of some macro- and micronutrients by peanut (Arachis hypogaea L. cv. Giza 6) grown on a sandy soil. Biological yield (pod + hay) as well as hay and seed yields were increased significantly as a result of K and gypsum application, but there was no significant increase under foliar spraying with B. The greatest values of 7788, 6585, and 954 kg fed?1 for biological, hay, and seed yields corresponded to 20.8 kg K fed?1 + 0.5 ton gypsum fed?1 without foliar spraying with B. For hay, the greatest value of N uptake was obtained with 20.8 kg K fed?1 + 1.0 ton gypsum fed?1, whereas the greatest values for P and K uptake (70.1 and 131 kg fed?1) were obtained when 20.8 kg K fed?1 + 0.5 ton gypsum fed?1 was applied under spraying with B. For seeds, the greatest value of K uptake was obtained when 20.8 kg K fed?1 + 1.0 ton gypsum fed?1 was applied, whereas for N and P uptake the greatest values (60.8 and 15.2 kg fed?1) were obtained when 20.8 kg K fed?1 + 0.5 ton gypsum fed?1 were applied under spraying with B. The oil yield of peanut seeds using the Soxhelt extraction method was found to be in the range of 23.1 to 35.2%. The greatest B uptake in hay was obtained without spraying with B, whereas in seeds it was obtained under spraying with B. In both of them was obtained upon application of 20.8 kg K fed?1 + 0.5 ton gypsum fed?1. Apparent K recovery (AKR) and K-use efficiency (KUE) were markedly decreased with increasing K addition rates.  相似文献   

19.
This study was implemented to determine effectiveness of various treatments in recovering boron (B)–deficient olive trees in the Marmara region. The study was carried out during the period 2000–2005. The experimental soil was in loamy texture with medium alkaline pH, low organic matter, and low B concentration. The experiment was conducted in a randomized plot experimental design with 12 treatments. In the study, different B fertilizers were applied to soil and leaves. Treatments of 125, 250, and 500 g?1 borax (sodium tetraborate) were applied to the soils at the beginning of the experiment to determine the later effects of sodium tetraborate. Treatments of 125, 250, and 500 g borax were applied to the soils every year in March. Also, 0.4% borax was applied two or three times, 0.8% sodium tetraborate two or three times, and 0.5% bor-track (boron ethanol amine) two times by foliar applications during the growing period. According to the results, two applications of 0.4% sodium tetraborate to the leaves gave the best results. Soil applications of 250 g sodium tetraborate every year and 500 g sodium tetraborate every two years were the most effective treatments.  相似文献   

20.
ABSTRACT

The growth of cotton (Gossypium hirsutum L.) was evaluated in a 6 × 5 factorial experiment with 6 boron (B) levels (0.0, 0.5, 1.0, 1.5, 2.0, and 3.0 mg dm?3), 5 cultivars (‘CNPA 8H’, ‘BRS Aroeira’, ‘BRS Antares’, ‘BRS Sucupira’, ‘BRS Ipe’), and 3 replications. As B increased in the soil, leaf B concentrations increased linearly in ‘BRS Aroeira’ and ‘CNPA 8H’, and quadratically in ‘BRS Ipe’ and ‘BRS Sucupira’. The concentrations of B in the leaves and in the soil increased with the B increasing in the soil. The agronomic characteristics evaluated showed ‘BRS Aroeira’ and ‘BRS Sucupira’ responding more and BRS responding less to the B doses applied. The variation in the effFiciency of B utilization was: ‘BRS Aroeira’ > ‘CNPA 8H’ = ‘BRS Antares’ > ‘BRS Sucupira’ > ‘BRS Ipe’. Cultivar ‘BRS Aroeira’ had the greatest potential to respond positively to the addition of B to the soil.  相似文献   

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