A simple system for raising clean‐rooted plants for solution culture experiments

Abstract

A simple arrangement is described for growing seedlings with clean roots for use in solution culture experiments. It consists of a deep level tray containing seed trays subdivided into modules filled with smooth coarse gravel. These are flooded periodically with nutrient solution using a pump and time switch. The solution then drains back into a reservoir underneath the tray. The system requires very little attention and spinach plants grew better in gravel than in sand or commercial peat‐based compost.     

Effects of potassium nutrition on the absorption of sodium,calcium, and magnesium by intact tomato plants

Abstract

Tomato plants (cv. VF145 B 7879) were grown in a greenhouse by the water culture technique with six levels of K nutrition. The absorptions of Na, Ca, and Mg were not affected greatly by the K nutritional status of the intact tomato plants, except when the plants were extremely K deficient. The rates of absorption by the intact plants were slow initially when the plants were small, and then increased rapidly as the growth rates increased.

At the onset of K deficiency, the rate of growth and water use by the tomato plant decreased. A linear function of water use and plant size was obtained, indicating that water use was a function of plant size and hence a function of the plant's nutritional status.

Waterlogging, simulated by aeration cut‐off of the culture solution for two days, had only a small effect on water use, but concurrently interrupted the absorption of K, Ca, and Mg.     

一种新型根系分泌物收集装置与收集方法的介绍

根系分泌物在养分活化、改善环境胁迫方面具有重要作用,很多科技工作者对根系分泌物的研究表现出极大兴趣,取得了一系列进展。但土壤栽培条件下,根系分泌物收集是一个难点。本文介绍了一种新型根系分泌物的收集装置与收集方法。该装置由根系生长箱和分泌物收集箱组成,植物在生长箱土壤中生长,通过定向引导作用,根系从生长箱穿过琼脂层进入收集箱中生长,待收集箱内积累一定根系后,通过淋洗收集箱内的介质,实现根系分泌物收集。研究发现,利用该装置收集分泌物,植物总根尖数的90%分布在收集箱。外源有机酸加样回收率可达70%以上。土壤栽培条件下,随生长时期延长,大豆有机酸分泌量逐渐增加,苹果酸分泌量高于柠檬酸。而且土壤栽培条件下大豆柠檬酸和苹果酸分泌量是溶液栽培时的11.4倍和6.7倍。上述研究表明,该装置可以用于土壤栽培条件下根系有机酸的分泌研究。     

Role of the rhizosphere in utilization of inorganic iron-III-compounds by corn plants

Using a nutrient solution with nitrate-nitrogen, a strong interaction between iron and phosphorus uptake in water culture was observed. Iron chlorosis could be prevented only by a very high supply of iron-III-hydroxide or a very low supply of phosphorus, both of which resulted in a normal chlorophyll content but produced plants deficient in phosphorus. However when iron and phosphorus were supplied to separate root zones (split-root technique), iron-III-hydroxide was a satisfactory source of iron for corn plants even in water culture. In contrast to corn plants grown in water culture, plants in sand culture (quartz sand) with the same nutrient solution utilized iron-III-hydroxide just as well as iron chelate, even when high phosphorus concentrations were simultaneously present. Using ⁵⁹Fe and circulating the nutrient solution through the sand culture, it could be demonstrated that the mobilization of iron from iron-III-hydroxide is restricted to the root-sand (iron-III-hydroxide) interface (rhizosphere) without increasing the amount of soluble iron in the bulk substrate. The depletion of phosphorus around the roots in sand seems to be particularly responsible for this “substrate effect” in the utilization of iron-III-hydroxide. The uptake of phosphorus and iron in sequence along a root growing in a solid substrate could be important in the iron nutrition of “iron-inefficient” plant species such as corn growing in soils of high pH.     

Microbial mineralization of organic nitrogen into nitrate to allow the use of organic fertilizer in hydroponics

Hydroponics is an excellent technique for the cultivation of vegetable crops and other plants, but organic fertilizers cannot be used in conventional hydroponic systems, which generally use only inorganic fertilizers, because organic compounds in the hydroponic solutions generally have phytotoxic effects that lead to poor plant growth. Few microorganisms are present in hydroponic solutions to mineralize the organic compounds into inorganic nutrients. In this article a novel and practical hydroponic culture method that uses microorganisms to degrade organic fertilizer in the hydroponic solution has been developed. Soil microorganisms were cultured by regulating the amounts of organic fertilizer and inoculum, with moderate aeration. The microorganisms mineralized organic nitrogen via ammonification and nitrification into nitrate at an efficiency of 97.6%. The culture solution containing the microorganisms was usable as a hydroponic solution, and organic fertilizer could be directly added to it during vegetable cultivation. Vegetables grew well in the organic hydroponic system. Organic hydroponics based on this method is therefore a practical tool for the utilization of organic sources of fertilizer.     

Effects of phosphate,nitrate and chloride on calcium,magnesium and manganese content of cigar‐wrapper tobacco

Abstract

Nutrient solutions containing three levels of phosphate, nitrate, and chloride were applied to cigar‐wrapper tobacco (Nicotiana tabacum L.) plants growing in sand culture for a period of 18 days. Concentrations of other nutrient elements in the nutrient solutions were held constant and the solutions were applied to pots as needed to maintain favorable moisture conditions for plant growth. Plants were in the two leaf stage when transplanted and were maintained on a single nutrient solution for 38 days before treatments were started. At the end of an eight weeks growing period, plant leaves were harvested and analyzed for Ca, Mg, and Mn. Dry matter yield was significantly (P=0.01) increased when 2 mM/1 of Ca(NO₃)₂ replaced an equivalent amount of Ca(H₂PO₄)₂ or CaCl₂ in the nutrient solution. Nitrate significantly (P=0.05) increased Ca and Mg content and decreased Mn concentration in leaf tissue in comparison to chloride. Calcium and Mg content were significantly (P=0.05) decreased and Mn content of tobacco leaves was increased by phosphate in comparison to nitrate and chloride.     

植物有机营养无菌培养试验方法的研究与应用

本文对植物有机营养研究中无菌培养实验室的结构,功能作了描述,对有机营养无菌水培液的配制及无蓝图苗的筛选和培育方法作了检验。用此无菌试验法进行的水稻有机氮营养试验证明,水稻能直接吸收根际营养液中的氨基酸,在频繁更换营养液的培养条件下,等氮量有机、无机 氮对对水稻的营养效果依次为甘氨酸态（无菌条件）〉谷氨酸态氮（无菌条件）〉铵态氮（无菌条件）〉铵态氮（常规条件）,反映出有机、无机氮种类及无菌、常规试验     

Excess sulfate supply and onion‐induced human antiplatelet activity

Awareness is growing of health‐promoting functional foods and the use of various plants as nutraceuticals. Due to a suite of organosulfur compounds, onion, and other vegetable Alliums possess a unique antiplatelet effect that may promote cardiovascular health because aggregating platelets can lead to heart attack and stroke. Investigation of the consequences of S nutrition in onion has primarily focused on levels of S ranging from deficiency to just above sufficiency; however, little work has been conducted to examine the effects of supraoptimal S nutrition on organosulfur‐based traits. Four onion selections were grown in hydroponic solutions with 2, 7, and 12 mM SO₄^2—‐S in greenhouse experiments during 1995—1996 and 1996—1997. Onion plants were separated into root, leaf, and bulb portions and analyzed for mineral content. Onion bulb extracts were assayed for in vitro human antiplatelet activity. Bulb and leaf S were not affected by increasing solution culture S, but root S was increased by 98 % when solution culture S was increased from 2 mM to 12 mM. Similar increases in root Ca and Al were detected, suggesting CaSO₄ and AlSO₄⁺ were accumulated in and on the root. No directional change in antiplatelet activity was detected as S was increased from 2 to 12 mM. This lack of significant change in antiplatelet activity with increasing S levels suggests that modification of this trait by simply increasing S levels may not be feasible in a solution culture environment.     

Loss of nitrogen from alkali soils

Practical agriculturists all over the world have reported losses of nitrogen from the fields when nitrogenous fertilizers are applied. They have observed that whole of the nitrogen is not utilized by the plants but a major Portion is lost as nitrogen gas. The inorganic mtrogen compounds -ammonia and nitratessUffer several types of loss from the soil. They may be taken up by growing plants, they may be assimulated into the bodies of microorganisms and so brought back into the organic nitrogen reservoir, they may be converted into volatile compounds and lost into the air or they may be leached out of soil.     

韭菜的雄性不育无性系育种

田间发现的韭菜(Allium tuberosum)无花粉单株经鉴定为雄性不育而雌性可育后，利用组织培养技术将此雄性不育单株迅速扩繁为雄性不育无性系并作为杂交的母本，与其它优良父本杂交，从F1中快速选出了优良品系J-54和新品种海韭一号。雄性不育无性系能长期稳定地试管保存。从3个F1杂种后代和2个品种的后代中选育出无花粉单株,并用组织培养建立了5个相应的雄性不育无性系.     

Effect of microbubbles in deep flow hydroponic culture on Spinach growth

Microbubbled air may be efficiently supplied to the culture solution, since microbubbles are more efficiently dissolved in water than millibubbles. To establish an enhanced air supply method in the hydroponic culture of vegetables, microbubbles were applied using the deep flow technique to a hydroponic culture system of spinach. Spinach was cultivated in culture solution treated microbubbles for 21 days, then harvested and measured growth and concentrations of inorganic components and chlorophyll in the leaf blade. The results showed that microbubbles applied to the culture solution promoted the growth of spinach more than that by millibubbles. Using microbubbles, cultivars maintained a high concentration of dissolved oxygen at the middle growth stage, during which the dissolved oxygen concentration in the culture solution was reduced by the active root respiration. This result suggests that microbubbles are more effective than millibubbles in the hydroponic culture of vegetables.     

Interactions Between Sulfur and Selenium Uptake by Corn in Solution Culture

Interactions between sulfur (S) and selenium (Se) uptake and accumulation in corn (Zea mays) plants were investigated in solution culture. Two concentrations (5 and 10 μ M) of Se (as selenate) and three concentrations of S (as sulfate) (0.5, 1.5, and 2.5 mM) were used. Results showed that shoot and root biomass were affected significantly by different S concentrations in solution, but not affected by Se application when S concentrations in solution were lower than 1.5 mM. Selenium concentrations as well as Se accumulation in shoots and roots on a dry weight basis increased dramatically with increasing Se concentrations in solution. At a constant Se level, increasing S in solution reduced Se concentrations. Selenium accumulation in plants was not affected by S application, except in nutrient solution with Se at a concentration of 10 μ M. Sulfur concentrations and S accumulation in shoots increased significantly with increasing Se concentrations in solution, while those in roots were unaffected by Se addition. Solution-to-shoot transfer factors and shoot-root distribution coefficients of Se and S were also discussed. These data suggest that it is necessary to manage carefully both S and Se levels in solution or in soils for supplementation of Se in plants. Results from this study indicate that human Se nutrition can be improved by supplementation of Se in crops.     

Der Einfluß der Kaliumkonzentration der ‘Bodenlösung’ auf den Ertrag,den Wasserverbrauch und die K-Aufnahmearten von Zuckerrüben (Beta vulgaris ssp. esculenta var. altissima)

The effect of the potassium concentration of the “soil solution” on the yield, the water consumption and the potassium uptake rates of sugar beets (Beta vulgaris ssp. esculenta var. altissima) . 1. The object of this experiment was to investigate which K concentration of the nutrient solution can be regarded as optimal for the growth of sugar beets. The nutrient medium was a quartz sand with a nutrient solution, of which the nutrient concentration could be controlled and corrected at any time due to a newly developed technique. Compared with a solution culture this technique enables a contact surface between the roots and the soil solution, which equals more field conditions. 2. The experment had three treatments with the following K concentrations: 0.2, 1A and 5.0 me K/1. These K concentrations were controlled and corrected by K additions and were kept approximately constant during the growing period. 3. The yields of beet roots and sugar of the treatment “0.2 me K” were significantly lower than the yields of the other two treatments. Although a K concentration of 5.0 me K means a considerable high concentration, the plants of this treatment did not show any depressive effects. Moreover this treatment (5.0 me K) showed the highest yield in beet roots and sugar, which, however, did not differ significantly from the yields of the treatment “1.0 me K”. It is concluded that this K concentration (1.0 me) of the nutrient solution can be regarded as optimal for sugar beet plants. Also under field conditions the order of magnitude of this K concentration in the soil solution may be optimal. 4. The daily uptake rates for K were the higher the K concentration of the nutrient solution was. This tendency was particularly obvious in the beginning of the growing period. In each treatments the highest K uptake rates were observed during the maximum leaf growth (2nd half of July). 5. High K uptake rates resulted mainly in a considerable increase of the K content of the leaves. But the total cation content (K, Na, Mg, Ca) of the leaves was not affected by these high K uptake rates. In the treatment “0.2 me K” the very low K content of the leaves was compensated quantitatively by higher contents of Ca and Mg. This replacement of K by Ca and Mg, however, could not substitute for the specific functions of K in yield formation. 6. The water consumption of the plants related to the weight unit beet roots was the lower the higher the K concentration of the nutrient solution was. Particularly during August and the 1^st half of September simultaneously with a higher production of organic material the better K supply resulted in an absolutely lower water consumption.     

二轴旋转式植物湿润栽培装置的研制

为了满足在地面进行空间植物生长试验和研究的需要,该文研制了能模拟空间微重力效应的二轴旋转式植物湿润栽培装置,介绍了该装置的总体设计、结构特点和工作原理。植物三维旋转栽培盘同时绕着2根相互垂直的旋转轴进行旋转,转速可独立在线无级调节。通过盘内植物湿润栽培介质材料筛选与优化组合,结合渗水管路和旋转水接口等关键部件的结构设计,介质始终保持整体湿润而外层表面无明水出现,且易于植物根部的固定,为植物生长提供良好的水、气、肥等生态环境。建立具备严格气密性的受控密闭舱,并配置植物生长监控和综合环境监测系统。应用试验分析表明,湿润栽培方法可以满足植物悬空低速三维旋转栽培的要求,装置各项性能指标均达到设计要求。     

类番茄茄基因渗入栽培番茄的研究

用栽培番茄作母本 ,类番茄茄作父本杂交 ,结实率为 40 %。通过离体胚培养获得杂种 1代 ,用栽培番茄作母本与之回交 ,得到回交 1代种子 ,结实率达 1 5 6% ,获得种子发育成苗 2 3株。但该回交 1代植株自交不结实 ,与栽培番茄 2次回交表现不亲和。用类番茄茄与栽培番茄的杂交 1代作母本 ,潘那利作父本杂交 ,结实率为 1 1 % ,得到复合杂种植株 5株 ,用该复合杂种作母本 ,潘那利作父本进行回交 ,结实率达 1 5 6% ,得到回交后代 2 5株 ,该代植株自交结实 ,并与栽培番茄杂交亲和。     

Nitrogen uptake efficiency of finger millet grown in hydroponic culture

The optimum nitrogen requirement along with nitrogen uptake efficiency of finger millet (Eleusine coracana) for obtaining plants of a high phenotypic quality was studied in this research using hydroponic culture. 20 days old seedlings were transferred in nutrient solution containing all the essential macro and micro nutrients. Plants were subjected to three treatments of nitrate viz. 0.05 mM, 0.1 mM and 0.5 mM by dissolving it in the nutrient solution. Plants grown in nutrient solution devoid of nitrate were treated as control. Plants grown in 0.5 mM nitrate conc. attained more height compared to other low nitrogen treatments (0.1 mM and 0.05 mM). Similarly plants of 0.5 mM nitrate treatments possessed more number of lateral roots, surface area of leaves, dry weight of plants and chlorophyll content compared to other low nitrogen treatments. Specific activity of nitrate reductase in plants treated with 0.5 mM concentration was found nearly 3 times higher than that of control plants; similarly, specific activity of nitrite reductase in 0.5 mM treated plants was also high compared to other low nitrogen treatments followed by control. The results of the present investigation therefore indicate that nitrogen uptake efficiency as revealed by the activities of nitrate reductase and nitrite reductase was high in 0.5 mM nitrate treatment. It also shows that 0.5 mM nitrate is optimum nitrogen concentration for the growth of finger millet in hydroponic condition.     

滨海盐土水、旱生境下田菁生长及其对盐土肥力的影响

蓄淡养鱼改良滨海强度盐渍化土壤＾（１）和种植田菁改良盐土已被广泛报道。为把有效的改良途径组装为一体,产生生态叠加效应,从１９９１年开始,在江苏滨海中度盐渍化土壤进行田菁水植养鱼改土试验研究。结果表明：１．在中度盐渍化土壤中田菁上田菁 水植养鱼复合处理其盛花期水植田菁根鲜重是旱作的１０倍,根瘤鲜重是旱作田菁的１５倍以上;田菁籽产量是旱培单作田菁的１．５倍以上。２．田菁 水植养鱼复合处理土壤脱盐效果明     

Evaluating Bearberry Nitrogen Nutrition Using Hydroponic Cultures: Establishing Preliminary DRIS Norms

Abstract

This study was designed to explore nitrogen (N) nutrition in bearberry plants (Arctostaphylos uva‐ursi L.) using a hydroponic culture system. Two experiments were performed in which the total N concentration (34, 52, and 73 mg L^?1) and N‐NO₃ ^?:N‐NH₄ ⁺ ratio (50/50, 60/40, and 70/30 in %) in the nutrient solution were varied and effects on nutrient uptake [N, phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg)] and foliar composition determined. Highest‐quality plants were yielded using a N level of 73 mg L^?1 and a N‐NO₃ ^?:N‐NH₄ ⁺ ratio of 50/50. Standard nutrient values for foliar tissue were obtained for bearberry plants growing in these hydroponic cultures for their use as preliminary norms in the diagnosis and recommendation integrated system (DRIS). In a subsequent complementary experiment, these norms were used in the DRIS procedure and applied to plants growing in solutions of varying K concentrations. It was found that the DRIS norms established in the hydroponic experiments were able to account for changes in nutrient limiting factors produced in response to the varying K concentrations in the nutrient solution. The results obtained will be useful for the nutritional diagnosis of bearberry plants.     

Inventory methods for finding historically cultivated hop (<Emphasis Type="Italic">Humulus lupulus</Emphasis> L.) in Sweden

The relationship between the conservation of plant genetic resources and their culture history is intimate. Consequently, biodiversity research must also take into account historical and cultural factors. An inventory of plants collected from all over Sweden was made with the aim of establishing a national Swedish gene bank for once cultivated hop. Only female hop, which could be regarded as cultivated hop on the basis of history, were selected. In this study, two different inventory methods were used: one based on plant habitat and the other involving the use of historical documents, primarily large-scale maps from the first half of the seventeenth century, used to locate their cultivars today. The documented history of the hop, combined with its biology, is the basis for the methods used. Hop is the only Swedish crop that according to a 1442 law had to be cultivated. The law lasted for over 400 years. Since the hop is a perennial, dioecious plant and only female individuals are cultivated, over time very few genetic recombination events are expected. Today, it is possible to connect and identify living plants using historical documents. The degree of connection between today’s living plants and the historical evidence for hop cultivation differ between the two methods.     

动物腔前卵泡的研究进展

综述了各种动物（鼠、兔、羊、牛、猪、猫和犬）腔前卵泡的研究历史和现状，主要讨论了腔前卵泡的分离方法、体外培养技术和培养液的添加成分等问题。