Einfluß verschiedener organischer Düngemittel auf die Effizienz von Azospirillum lipoferum

Effect of several organic manures on the efficiency of Azospirillum lipoferum
Under greenhouse conditions, it was examined how grass mulch, farmyard manure and compost influence the efficiency of Azospirillum lipoferum with Sorghum bicolor. The organic manures were added at 5 concentrations: 0, 50, 100, 200 and 300 dt/ha.
With the exception of the highest amount the grass mulch always induced a good effect of Azospirillum on plant yield and nutrient uptake. The application of farmyard manure or compost did not improve the growth of the inoculated plants. With farmyard manure the inoculation even lowered shoot dry weights. But in both treatments the inoculated plants showed considerably increased N and P contents. In addition to the N₂ fixation the inoculation with Azospirillum lipoferum apparently can increase the capacity of the sorghum plant roots to absorb P. Primarily, the organic manures create better growing conditions for the bacteria and simultaneously serve as P sources.     

Untersuchungen zum Einfluß von Standort, Saatstärke, N-Düngung, Sorte und Erntezeitpunkt auf den Ertrag und die Inhaltsstoffe von Zuckerhirse

Investigations into the effect of location, planting density, N-fertilization, variety and harvest date on yield and contents of sweet sorghum
Looking for high yielding plant species as renewable resources, sweet sorghum ( Sorghum bicolor [L.] Moench) seems to be an interesting crop.
In field trials at three locations in the south-west of Germany in 1983 and 1984 should be investigated the effect of N-fertilization, planting density, variety and harvest date on yield, different morphological characteristics and contents of sweet sorghum.
The results indicate that yields of 15-20 t DM/ha are only feasible when the given temperature sum is higher than 2000 °C (> 5°C). The maximum yield of 22.7 t DM/ha resp. 6.5 t/ha "Free Fermentable Sugar" (FFZ) was realized when a sufficient water supply and N-fertilization had been guaranteed.
The different possibilities of utilization of sweet sorghum e.g. as sugar crop, agricultural raw material for combustion or as forage crop urge the plant breeder to intensify the breeding efforts adapting this crop at the climatic conditions of Germany.     

Response of confection sunflower (Helianthus annuus L.) grown in a semi‐arid environment to planting date and early termination of irrigation

Adjustments on planting date and on the time to terminate irrigation may reduce agricultural water use. However, such management practices in regions with extreme weather conditions have the potential to negatively affect yield. A 3‐year (2012–2014) study was conducted on a clay‐loam soil in a cool, semi‐arid environment to (i) determine the response of confection sunflower to planting date and irrigation termination timing and (ii) identify the relative importance of yield components in irrigated confection sunflower across planting dates. Early May planting had considerable negative effects on all studied variables, except on the percentage of large seeds. The highest yield of total and large seeds was obtained from the late May plantings, averaging 3,777 and 3,379 kg/ha, respectively. None of the irrigation strategies affected the measured variables. However, the interaction between planting date and termination of irrigation significantly affected the 1,000‐seed weight. Our study revealed the last week of May as suitable planting period for confection sunflower in the semi‐arid north‐western region of Wyoming, USA, and that irrigation on heavy soils may be terminated as early as at R5.5 stage without a significant yield reduction. The path‐coefficient analysis indicated head diameter and the number of seeds per head as important traits that significantly influence the yield of confection sunflower across planting dates.     

Ergebnisse zur Ertragsbildung bei ökologisch orientiertem Winterweizenanbau auf Lößschwarzerdeböden in trockenen Lagen

Results of yield formation at ecological oriented winter wheat cultivation on Calcic Chernozem soil in arid areas
The influence were examined in field experiments of wheater elements (air temperature, precipitation), nitrogen fertilization, sowing rate and irrigation on the yield and yield formation of winter wheat stands. The average level of yields amounts to 81.3 dt/ha (76…93.8 dt/ha). Limiting factor for yields is the availability of water in the soil. In humide seasons 9…12 % higher yields were obtained then in dry seasons. Without nitrogen fertilization yields of winter wheat are lower by 18 % than with nitrogen fertilization. At very high level of N fertilization only vegetative biomass increases, and the water use efficiency decreases.
Increase in plants/m² caused a rise of vegetative biomass and of ears/m², kernels per ear strongly decreased in the same time. At winter wheat cultivation in low input farming systems without nitrogen fertilization high yields will be obtained with 320…370 plants/m² and 15,000 kernels/m². Nitrogen uptake from the soil amounts to 180 kgN/ha. Because of great amounts of inorganic in the soil (70…200 kgN/ha) sufficient nitrogen is available until heading of the wheat plants. The nitrogen supply of wheat plants in later stages of development is influenced by wheater conditions.     

Effect of Soil and Foliar Fertilization on Inoculated and Uninoculated Soybeans

Two experiments of soil N-fertilization and Rhizobium inoculation were conducted in 1981 and 1982 at Giza, Egypt. Soybean was sprayed with a commercial micronutrients mixture, and with urea.
In the first experiment, soil N-fertilization 0, 142.8 and 214.2 kg N/hectare were applied to uninoculated plants, whereas, in the second one, local inoculum was used alone or along with addition of a starter dose of N (47.6 kg N/hectare).
Urea applications were at pod filling period (R₄, R₅ and R₆ stages), whereas, micronutrients mixture was applied at 25 days from planting.
Plant dry weight, leaf area/plant, plant height, pod and seed number/plant, seed weight/plant, seed yield and crude seed protein content increased significantly with nitrogen application to uninoculated soybean plants; whereas the starter dose of N had no significant effect on any of these traits under the inoculated soybean plants.
Foliar application of micronutrients caused significant increases in plant DW, LA, pod and seed number/plant, seed index and seed yield of fertilized and inoculated plants.
Foliar application of urea, to inoculated and uninoculated plants, caused significant increments in plant dry weight, 1A, seed protein content and particular seed index and seed yield.     

Stickstoffaufnahme und Stickstoffrückstände von Hauptfrucht-und Ausfallrapsbeständen

Nitrogen Uptake and Nitrogen Residuals of Winter Oil-Seed Rape and Fallout Rape
The objective of the investigation was a study of the relationship between seed dry-matter production and vegetative dry-matter production in oil-seed rape crops and their dependence on the production conditions. In addition to the relationship between the N-uptake during the vegetation period and the N-residue after harvest was of major interest. Furthermore the potential for N-uptake in fallout rape was measured. Over two vegetation periods factorial field experiments with winter oil-seed rape, cv. Lirabon, different drilling techniques and different nitrogen fertilization levels were tested. Measured traits were: the dry-matter accumulation including root mass and fall-off leaf-material mass, the N-uptake of both the oil-seed crops and the fallout rape stands, and, simultaneously, the soil NO₃-N content. Finally the harvest indices and the N-harvest indices were calculated.
Combined with a N-uptake of up to 330 kg N/ha, oil-seed rape crops produced up to 200 dt dry matter/ ha. At seed yield levels of 33dt/ha (d.m.), harvest indices varied from 0.14—0.23 and N-harvest indices varied from 0.30–0.50. As a result of the residue of vegetative plant material at harvest, leaf losses before harvest and the soil NO₃-N-contents at harvest up to 275 kg N/ha remained in the field. After the harvest of oil-seed rape, the soil NO₃-N-contents were quickly reduced by emerging and growing fallout rape stands. However, following soil-preparation measures in the autumn, a continuous rise in the soil NO₃-N-content was observed.     

Über den Einfluß von Trockenstreß in unterschiedlichen Entwicklungsphasen auf Wachstum, Blütenabwurf und Ertrag der Sojabohne (Glycine max [L.] Merr.)

The influence of droughtstress during various growth phases on yield parameter and flower drop of the soybean (Glycine max [L.] Merr.) was studied in a pod trial under arid conditions at Alexandria/Egypt. The two cultivars Calland and Williams do not differ in their reaction to droughtstress.
The seed yield was decreased by ca. 18% when two weeks of drought occurred. Droughtstress during the seed filling phase reduced the yield by 25%. This decrease in yield is due to a decrease in pod number and seed number per plant. Flower drop on the main stem is not influenced by droughtstress and there is no relation to the seed yield per plant.     

Effect of Agronomic Factors on Annual Leguminous Forage Crop in Mediterranean Environments

Dry matter and seed production of five annual leguminous species hairy vetch ( Vicia villosa Roth cv. Orsara) , crimson clover ( Trifolium incarnatum L. ecotype Campano) , squarrosum clover ( T. squarrosum L. ecotype Calabro) , persian clover ( T. resupinatum cv. Accadia) and fenugreek ( Trigonella foenum-graecum L. ecotype Maltese) was estimated in 1989–90 under two density and irrigation rates and with two cutting treatments. The experiments were done at the Forage Crops Institute of Foggia, which has a typical Mediterranean environment. The forage cut severely affected the regrowth of the plants in all species. The year and irrigation factors affect dry matter, seed production and seed yield components more than the plant density rates. The averages over the years, for dry matter and seed yield were 21.0 % and 20.5 % higher in the irrigated than the not irrigated ones. The lower plant density rate, for seed yield trait, gave better result in hairy vetch in irrigated and non-irrigated treatment. Whereas in the other species, the lower rate of planting gave greater yield under non-irrigated and the higher rate under irrigated growing condition. The seed yield components most influenced by irrigation were: thousand seed weight and seeds/pod in hairy vetch and heads/tiller and seeds/head in clovers species. Fenugreek was the earliest forage crop (cut at the beginning of March), followed by crimson and persian clovers (cut at the middle of April) and squarrosum clover and hairy vetch (cut in the middle-late of May). All the cultivars and ecotypes considered not regrowth after cut and could represent an important fresh forage resource for the period March–May for the Mediterranean regions.     

Einfluß von sterilisiertem und nichtsterilisiertem Stallmist und Kompost auf die Effizienz der VA-Mykorrhiza

Effect of sterilized and unsterilized stable manure and compost on the efficiency of VA mycorrhiza
Under greenhouse conditions, it was examined how the three organic manures stable manure, compost out of stable manure and compost out of plant rests in comparison with the corresponding amounts in sterile and homogeneous form, influence the efficiency of VA mycorrhiza cultivated with Capsicum annuum. The manures had been added in 4 stages of concentration: 50, 100, 200 and 300 dt/ha.
In the unsterile treatment the generally positive efficiency of VA mycorrhiza on plant yield decreased with increased amounts of the organic manures. How fast this reduction took place, was dependent on the different kinds of manures. The effect of the inoculation were much better in the unsterile treatment, compared with the sterile one, when the offer of the possible nutrient sources by the manures were low and the relation of the nutrients in the soil solution were unfavorable. The activity of the soil microorganisms always have played a decisive role for this results.     

定位水氮组合对冀5265小麦叶片硝酸还原酶、可溶性蛋白及产量的影响

为生产中水氮高效利用提供依据,在3年定位水氮处理的基础上,于2008-2009年在大田条件下研究水氮组合对小麦叶片硝酸还原酶活性(NRA)、叶片可溶性蛋白含量及产量的影响。结果表明,在同一施氮水平上,开花期灌水显著提高NRA、可溶性蛋白含量和产量。灌1水条件下,随施氮量的增加叶片NRA、可溶性蛋白含量呈线性增长,在水分较适宜的2水灌溉条件下,叶片NR活性、可溶性蛋白含量均呈抛物线趋势,NRA在全年施氮240 kg/hm2时最高、可溶性蛋白含量在施氮480 kg/hm2最高,增加施氮量呈下降趋势。在灌2水全年施氮480 kg/hm2时产量最高,说明增加灌水有利于氮素增产效应的发挥。     

N-Dynamik des Bodens, Ertragsbildung und Stickstoffentzug von Winterweizen bei unterschiedlicher Höhe und Verteilung der mineralischen N-Düngung

NO₃ dynamics in the soil, yield formation and N uptake of winter wheat as influenced by dosage and distribution effects of N-fertilizer application
In a 4 year series of field trials carried out with 9 regimes of nitrogen fertilizer application at two trial sites with rather shallow top soil layers but large deviations in soil characteristics, grain yield varied between 50 dt/ ha and 120 dt/ha with nitrogen doses from 0–170 kg N/ha. Soil nitrogen supply for wheat grain formation on unfertilized plots reached 80 kg N/ha/year within the narrow range of 75–95 kg N/ha in different years at both sites which amounts to 1.5 % and 0.5 % of the highly different N-content of the trial sites.
The most successful nitrogen application regimes are characterized by modest fertilizer doses in early spring and the delay of supplemental fertilizer doses until growth stage EC 32. They resulted into modest NO) soil content from EC 29 to EC 32 and/or a noticable decrease of soil NO₃ content during growth stage EC 30–32, which seems to be responsible for the development of only modest stand densities and reduced straw yield, while the delayed supplementation with nitrogen fertilizer overcompensated these effects mainly by increased grain numbers/ear and a remarkable improvement of harvest index.
The contribution of soil borne nitrogen to kernel yield formation started to decrease with even low dosages of supplemental nitrogen fertilization with the exception of the highest yielding season 1987/88. Top levels of grain yield have been regularly obtained with supplemental nitrogen fertilizer dosages about 40 kg N/ha below grain yield nitrogen extraction if they were added within favorable application regimes.     

Water Use and Seed Yield of Horsegram Under Different Moisture Regimes and Mulches in Semi-Arid Region of Eastern India

In a two years field study on effect of irrigation at vegetative and flowering stages occurring at 40 and 60 days after sowing, respectively alongwith straw mulch ca. 5 t/ha were found to have beneficial effect on growth, yield attributes and seed yield of horsegram ( Dolichos biflorus Roxb.). Application of mulches significantly increased pods/plants, seeds/pod, test weight and seed yield and maintained better soil moisture during crop growth in semi-arid lateritic region of Indian sub-tropics. Mulches proved useful to conserve more moisture in soil profile and thereby increased the water use efficiency of the crop; straw mulch was found superior to leaf mulch.     

Yield and Seed Quality of Mungbean as Affected by Irrigation in a Dry Season

A field study was conducted with the objective of determining the effects of soil moisture on seed yield and quality of mungbean ( Vigna radiata L. Wilczek) when grown under rainfed and irrigated conditions in a dry season. Seed quality was determined in terms of germination and production of normal seedlings after controlled deterioration. The presence of adequate soil moisture increased growth and yields of mungbean significantly. The seeds from irrigated plots had a greater weight, owing to heavier cotyledons. Although germination of seeds from the irrigated plots was higher before and after controlled deterioration for 72 h, the number of abnormal seedlings was also greater. Controlled deterioration reduced germination of both categories of seed in the same manner. These factors indicate the low potential of using seeds produced under irrigation in dry seasons as planting material, especially after storage.     

Effect of Deep Placement of N Fertilizers and Different Inoculation Methods of Bradyrhizobia on Growth,N2 Fixation Activity and N Absorption Rate of Field‐grown Soybean Plants

The effects of deep placement (supplied at 20 cm depth from soil surface below plants) of 100 kg N ha^?1 of N fertilizers, urea, coated urea or calcium cyanamide (lime nitrogen) on the growth, nitrogen fixation activity, nitrogen absorption rate and seed yield of soybean (Glycine max L. Merr.) plants were examined by comparing them with control plots without deep placement of N fertilizer in sandy dune field. In addition, three different inoculation methods of bradyrhizobia were used for each N treatment: (1) transplantation of 10‐day‐old seedling in a paper pot with vermiculite inoculated with Bradyrhizobium japonicum USDA110, (2) direct transplantation of inoculated 10‐day‐old seedlings, and (3) transplantation of 10‐day‐old seedlings in a non‐inoculated paper pot. The deep placement of N fertilizers, especially calcium cyanamide and coated urea, markedly increased the growth and total N accumulation in shoot, roots and nodules, which resulted in an increase in seed yield. Daily N₂ fixation activity and N absorption rate were estimated by relative abundance of ureide‐N analysed from the concentration of N constituents (ureide‐N, amide‐N and nitrate‐N) in root bleeding xylem sap and increase in total N accumulation in whole plants at R1, R3, R5 and R7 stages. The total amount of N₂ fixation was about 50 % higher in the plants with calcium cyanamide and coated urea deep placements compared with control plants. Deep placement of slow release fertilizers kept nodule dry weight higher in the maturing stage of seed, possibly through abundant supply of photoassimilate to the nodules by supporting leaf area and activity until late reproductive stages. The results indicate that deep placement of calcium cyanamide or coated urea enhances N₂ fixation activity, which ultimately increases the seed yield. The promotive effect was observed with the seedlings transplanted in paper pot with inoculum of bradyrhizobia within any treatments, although nodulation by indigenous rhizobia was observed in the plants transplanted with non‐inoculated paper pot.     

Zum Einfluß von Saatzeiten, Saatstärken und Sorten auf agronomische Merkmale von Winterweizen in einem System mit geringer Betriebsmittelzufuhr von außen

The influence of sowing date, seed rate, and variety on agricultural characteristics of winter wheat in a low external input system
Growth conditions of winter wheat in agricultural low external input systems, e.g. ecological agriculture, are very different compared to conventional agriculture (mineral nutrition, impact of diseases, competition of weeds). In 1986, 1987, and 1988 the influence of sowing date and seed rate on crop development and grain production was studied with two varieties of winter wheat in field experiments in Northern Hessia.
Drilling after the first decade of October decreases grain yield of both varieties significantly. The decrease was due to poor emergence, low plant densities, and low grain weights. Tillering could not compensate low plant densities, presumably because of low mineralization of nutrients in cold soils during respective growth stages.
Variation of seed rate (350, 500, and 650 viable seeds/m²) had little influence on grain yield. Low plant densities and low numbers of ears per nr after sowing in the end of October could not be improved satisfactorily by increased seed rates.
The ability of varieties of winter wheat to compensate unfavourable growth conditions due to "late" sowing varies considerably. Cultivars which are able to develop a high plant density seem to be more suitable for delayed sowing dates, as compared to varieties which own a high grain weight.
Further investigations concerning wheat production are needed to optimize agricultural low external input systems. Especially sandy soils with quick response to increased ambient temperature, and sites with favourable growth conditions in late autumn and early spring should be considered.     

Response of Rapeseed (Brassica napus L.) Growth, Yield, Oil Content and Its Fatty Acids to Nitrogen Rates and Application Times

A steady and progressive increase in rapeseed yield was observed with each increment in applied nitrogen rates up to 213 kg/ha in both seasons. As for nitrogen application times, the analyzed data showed that adding a split dose (either 1/2 or 1/3) before the third irrigation was a common part between high yielding treatments in 1985/86 season. Nitrogen rates X application times interaction affected rapeseed yield significantly during the first winter season. The highest seed yield of 2.5 t/ha was obtained by adding 213 kg N/ha in two split doses at sowing and just before the third irrigation. The second yield value of 2.47 t/ha was produced under the same N rate when applied in two split doses before second and third irrigation. However, in the second season (1986/87), rapeseed plants did not exhibit significant responses to nitrogen rates X application times interaction.
Chemical analyses showed that rapeseed oil content and its fatty acids (Palmetic, Stearic, Oleic, Linoleic, Linolenic, Arachidic and Erucic) percentages were not significantly affected by either nitrogen rates or application times in both seasons. A very low content of Erucic acid (0.1–0.9 %) in all tested sample was noticed.     

Reproductive response of two morphologically different pea cultivars to drought

Water use by semi-leafless peas (Pisum sativum L.) is usually less than that of conventional peas because of their reduced surface leaf area, suggesting that semi-leafless peas would be less sensitive to drought because drought develops later. This work aimed to study the reproductive response of peas cv. Solara (semi-leafless) and cv. Frilene (conventional) subjected to similar controlled soil drought during the critical period occurring between flowering and initial seed filling. Plants were subjected to drought by watering with a fraction of water used in the evapotranspiration of control plants. Soil, pod and seed water contents, leaf water status parameters, dry matter (DM) partitioning, seed yield, yield components and water use efficiency (WUE) were measured. Although soil water content decreased in a similar way in both cultivars, leaf Ψ_w and RWC only decreased significantly in Solara. Well-watered Frilene plants produced higher shoot and pod DM, but lower seed DM. Well-watered Solara plants produced lower pod DM and higher seed DM than Frilene. Under drought, Frilene increased partitioning of total plant DM to vegetative organs, particularly roots, and decreased DM allocation to pods and seeds increasing flower abortion. By contrast, droughted Solara interrupted vegetative growth and increased leaf senescence but maintained similar partitioning of total plant DM to pods and seeds as in well-watered conditions. For both cultivars there was a close relationship between the percentage of total DM partitioned into seeds and WUE_y (water use efficiency on seed yield basis). Results demonstrate that when plants suffered the same level of drought in the soil, the reproductive response of the two cultivars was linked to differences in their WUE.     

密度对超高产春大豆农艺性状的影响

研究了超高产条件下,不同种植密度对春大豆植株性状、产量性状和产量的影响以及单株叶面积和叶面积指数变化特点。结果表明,随密度的增加,株高和底荚高度增高,茎粗、节数、分枝数、分枝总长度降低,倒伏加重,单株有效结荚数、单株粒数、单株籽粒重降低,百粒重与种植密度关系不显著。叶面积指数随密度增加呈上升趋势,以45.0万株/hm2处理最佳,产量达5547.81kg/hm2。     

A maximin–minimax approach for classifying soybean genotypes for drought tolerance based on yield potential and loss

Screening for drought in soybean is often a bottleneck in plant breeding programmes. Sixteen genotypes were evaluated for drought tolerance during 2012, 2013 and 2014. The experiment was conducted in a split‐plot design, and the main plots consisted of irrigated and water stress treatments, and subplots consisted of 16 genotypes. The average seed yield was highest in 2012 (1708 kg/ha), followed by 2014 (1364 kg/ha) while very low yields (958 kg/ha) were observed during 2013. The per cent reduction in average soybean yield under water stress conditions was maximum (43%) during 2014 followed by 2012 (40%) and 2013 (31%), respectively. The average yields of soybean genotypes also differed significantly, which ranged from 892 (NRC 12) to 2008 kg/ha (JS 97‐52). The maximin–minimax approach was used to classify these genotypes, and only, one genotype was identified as drought resistant and high yielding (EC 538828), three as tolerant and high yielding (JS 97‐52, EC 456548 and EC 602288) and none as low yielding and resistant, while the remaining 12 genotypes were found to be low yielding and susceptible to drought.     

密度对超高产春大豆农艺性状的影响研究

研究了超高产条件下，不同种植密度对春大豆植株性状、产量性状和产量的影响以及单株叶面积和叶面积指数变化特点。结果表明，随密度的增加，株高和底荚高度增高，茎粗、节数、分枝数、分枝总长度降低，倒伏加重，单株有效结荚数、单株粒数、单株籽粒重降低，百粒重与种植密度关系不显著。叶面积指数随密度增加呈上升趋势，以45.0万株/hm2处理最佳，产量达5547.81kg/hm2。