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A strict two-factor field experiment was set up as a randomized complete block design over 2000-2002 at the Experimental Station of the Faculty of Agriculture, University of Technology and Agriculture, at Mochełek, and involved a traditional yellow lupin cultivar, `Idol´, whose plants were sprayed with Tytanit preparation, containing 46% of Ti. The first factor covered the following objects: three spraying dates: single spraying after blossom fall, double spraying - after blossom fall and 7-10 days later and triple spraying - after blossom fall, 7-10 days later and then 7-10 days later. The second factor involved the following objects of Tytanit concentration: 0.02, 0.04 and 0.06%. The plots which were not sprayed constituted the control. Throughout the research years there was observed a significant effect of Tytanit on 7.4-18% increased yellow lupin seed yield. Tytanit did not show a significant effect on the structural components of the seed yield from the main stem; its application resulted in a significant, as compared with the control, increase in the number of pods and seeds as well as in the seed weight from branches. As for yellow lupin yielding, the optimal solution seems to be offered by a double application of 0.02-0.04% of Tytanit straight after plant blossom fall and 7-10 days later.
This study was conducted to examine the seasonal dynamics of biomass and plant nitrogen (N) content under three grazing intensities (light grazing – LG: 1.2, moderate grazing – MG: 2.0, and heavy grazing – HG: 2.9 yaks ha⁻¹) in representative alpine meadow on the eastern Tibetan Plateau. Differentiation in grazing intensity in the study area started since 1997 and has continued to the present time. Plant samples were collected in the middle of June, August and September. The highest aboveground biomass occurred at the MG site for both August and September. Over the growing season, belowground biomass (0–30 cm) increased as grazing intensity increased. The total belowground biomass averaged over all sampling dates was 1226, 1908 and 2244 g m⁻² for LG site, MG site and HG site, which accounted for 75, 81 and 88% of total biomass, respectively. The results suggested that grazing intensity changed biomass allocation pattern between aboveground and belowground parts of plants. Higher grazing intensity resulted in higher N concentration in both live and dead aboveground biomass over the study period. Increased grazing intensity tended to increase plant N content averaged over all sampling dates, which were 17.9 g m⁻², 23.8 g m⁻² and 27.6 g m⁻² in LG site, MG site and HG site. The results indicated that higher grazing intensity had a potential to increase the ecosystem pool of plant N.
Using multiple classification approach to examine plant traits response to grazing and fencing (as without access to grazing) is rare. Here we used multiple classification approach to examine plant diversity, productivity and species traits response to grazing and fencing over a three-year period on the eastern part of the Qing-Hai Tibetan Plateau. The results showed that most common species response to the fence was poorly noticeable. The fencing meadows compared to those under long-term free grazing are characterized by significantly higher total species richness, but species richness declined with sampling years gradually, regardless of grazing or fencing. The correlation showed that species richness was negatively associated with mean annual temperature significantly, suggesting that abiotic factors (e.g. annual temperature) could also play important roles in driving species richness in this subalpine meadow. Total aboveground biomass was not associated with mean annual temperature and rainfall. The fencing meadow demonstrated higher community aboveground biomass relative to the grazing ones, especially the abundance of legume and graminoids increased, while the proportions of sedge decreased, suggested that grazing disturbance favours the increase of reproductive success of sedge (e.g. Kobresia humilis) in this subalpine meadow. Growth form-based analyses combined with canopy height categories should be recommended to reveal general rules and mechanisms relating to grazing.
В 1982 - 1985 гг. был реализован вступительный этап исследований по сравнению трех специалистических 3-полевых севооборотов удобряемых стойловым и жидким навозом в условиях легкой почвы (7 - 14% илистых частиц и 1,1 - 1,2% гумуса). Ход погоды в отдельные вегетационные периоды приводил к значительным колебаниям урожаев. Между прочим также и по этой причине возделывание растений в специалистических севооборотах не показало до сих пор связи их урожайности с системами чередования. Оценка севооборотов с энергетической точки зрения (основная цель опыта) позволила выделить следующую модель севооборота: картофель - яровой ячмень - кукуруза; в данном случае в среднем для 4 лет получено 7121 овсяных единиц с гектара. Более эффективным оказалось удобрение стойловым навозом в дозе 30 т/га однократно в трехлетием севообороте, чем двухкратное внесение жидкого навоза в дозе разделенной по 40 м³/га.
In order to investigate the influence of exogenous application of calcium (Ca) on its accumulation in finger millet, two genotypes (GPHCPB-1 and GPHCPB-45), which posses low and high grain Ca contents, respectively, were subjected to regular fertigation of varying levels of Ca in Hoagland’s nutrient medium. The responsiveness of both the genotypes towards increasing exogenous application of Ca (0.1, 5.0, 10 and 20) was determined in terms of changes in tissue Ca levels, agromorpho-physio-biochemical parameters. Sharp increase of Ca content in root, stem and spike was observed up to excess level of Ca (10 mM) in GPHCPB-1 while in case of GPHCPB-45 an increase in Ca content was observed only up to sufficient level of Ca (5 mM) and above that its accumulation remained constant or declined in both the genotypes. In case of leaf the level of Ca increased linearly at all concentrations of supplied Ca in both the genotypes. Both the genotypes behave differentially as GPHCPB-45 genotype accumulated more Ca and was also superior in root length, root dry matter accumulation, plant height and relative water content at Ca deficient condition (0.1 mM) as compared to GPHCPB-1 genotype. The continuous rise in stem diameter, biomass, seed yield, chlorophyll content, SPAD value, seed oxalic acid and phytic acid content were recorded in both the genotypes up to excess or toxic levels of supplied Ca. On the basis of present study it was concluded that Ca accumulation in plant is determined by both genetic (genotype dependent) as well as environmental factors (availability of Ca in rhizosphere).
This study was carried out during the winter seasons of 2016 and 2017 at private farm in Beni Suief Governorate, Egypt to investigate the integrative use of potassium levels (24, 48, 72 and 96 kg K₂O fed⁻¹) and soil mulching (rice straw and bare soil) on growth and productivity of garlic under three levels of surface irrigation (60, 80 and 100 % of crop evapotranspiration (ETC)). The experimental layout was a spit-spilt plot system based on Randomized Complete Blocks Design. Irrigation levels, potassium rates and mulch types were randomly allocated in the main, sub and sub-sub plots, orderly. The obtained results showed that, the amount of irrigation at 80 and/or 100 % ETC was accompanied increases by plant height, leaves number, leaf area and dry weight plant⁻¹, total bulbs yield, individual bulb weight, cloves weight and number bulb-1 compared to irrigation 60 % ETC. The application of potassium from 24 to 48 and further to 72 and 96 kg K₂O fed⁻¹ gave gradual increments in the aforementioned growth and productivity of traits. The rice straw mulch augmented all previous growth, total bulbs yield and its components compared to bare soil. Generally, the 1st order interaction between irrigation percent at 100 and/or 80 % ETC × potassium rate at 96 and/or 72 kg K2O fed⁻¹, irrigation percent at 80 and/or 100 % ETC × rice straw, potassium rate at 96 kg K2O fed⁻¹ × rice straw and the 2nd interaction of irrigation percent at 100 % ETC × potassium rate at 96 kg K₂O fed-1 × rice straw mulch had pronounced effects on morphological characters and bulbs yield and its components compared to other combined treatments.
This paper concerns the influence of a single application of various doses of or- ganic-mineral fertilizer, combined with yearly application of ammonium nitrate, and a single application of manure plus NPK, on the content of nitrate and ammonium nitrogen in the soil, considering the soil moisture. It was found that application of organic-mineral fertilizer at the dose of 12 t ha-1 plus N, caused a significant increase of the nitrates content in the soil. The content of ammonium nitrogen in the soil did not vary in the years, independently of the fertilizer doses. The nitrate nitrogen content in the soil was dependent on the moisture conditions, the lower the water content, the higher that of nitrates in the soil. The moisture content had a greater impact on the mineral nitrogen content in the soil than the applied fertilization. With the plants growth and development, the nitrate content in the soil decreased, which indicates a steady uptake of this nitrogen form by the plants during the whole growing season. In the case of ammonium nitrate no such connection was found, and the ammonium content in the soil was stable. The nitrates content in the soil was higher than that of the ammonium forms, in the course of the whole experiment.
W latach 1997–2000 oceniano produkcyjność pszenżyta jarego uprawianego w płodozmianie i monokulturze w różnych fazach rozwojowych. Wykazano, że produkcyjność pszenżyta jarego (plon suchej masy części nadziemnych i korzeni) była w każdej fazie rozwojowej istotnie większa w płodozmianie niż w monokulturze. Udział korzeni w całkowitej suchej masie pszenżyta jarego był największy w fazach: pełnia krzewienia - otwieranie się pochwy liściowej. Uprawa pszenżyta jarego w monokulturze istotnie zwiększała porażenie roślin przez choroby podstawy źdźbła oraz powietrznie suchą masę chwastów, w stosunku do płodozmianu. Przyczyniło się to do zmniejszenia obsady roślin i produkcyjności łanu.
W badaniach, prowadzonych w latach 1979-1983, na glebie płowej wytworzonej z lessów, określono działanie różnego udziału międzyplonów (rzepak ozimy i koniczyna perska), uprawianych jako rośliny regenerujące glebę, na produkcyjność płodozmianów zbożowych. Stwierdzono, że zwiększenie koncentracji międzyplonów w płodozmianie do 40% powodowało spadek jego produkcyjności.
Seedlings of various provenances and progenies were greenhouse grown in sand cultures with different levels of nitrogen, phosphorus, potassium, calcium and magnesium. The first experiment tested 20 provenances and the next studied 45–50 half-sib families of 9–10 provenances to establish the interaction between Picea abies genotypes and nutrition levels. Spruces of various origins differed in their nutrient requirements. In particular, seedlings from Wisła and Istebna grew better at smaller phosphorus levels. The genotype × environment interactions were significant for numerous traits when seedlings were grown at different levels of nitrogen, phosphorus and calcium, and for a few traits for potassium. The proportion of variance explained by interaction was small. Generally, the interactions were significant for a greater number of traits at progeny level than at provenance level. The results suggest that it is possible to select genotypes which are suitable for specific site conditions and genotypes which are stable over a wide range of nutrition levels.
Doświadczenie polowe przeprowadzono w latach 2005-2007 w Rolniczej Stacji Doświadczalnej Zawady, metodą losowanych podbloków w układzie split- plot w trzech powtórzeniach. W doświadczeniu analizowano cztery sposoby odchwaszcza: obiekt kontrolny (pielęgnacja mechaniczna) i trzy warianty pielęgnacji mechaniczno-chemicznej z użyciem herbicydów Plateen 41,5 WG, Racer 250 EC, Sencor 70 WG oraz dwie odmiany ziemniaka Balbina i Irga. Celem podjętych badań było określenie zależności pomiędzy zachwaszczeniem a masą bulw z jednej rośliny, liczby bulw z jednej rośliny oraz masy jednej bulwy. W celu określenia tych zależności obliczono współczynniki korelacji i równania regresji. Zastosowana w wariantach 2-4 pielęgnacja z użyciem herbicydów (Plateen 41,5 WG, Racer 250 EC i Sencor 70 WG) przyczyniła się w znacznym stopniu do zwiększenia struktury plonu, w porównaniu z obiektem kontrolnym. Największą średnią masę bulw z jednej rośliny oraz średnią masę jednej bulwy uzyskano stosując do wschodów obredlanie połączone z bronowaniem, a tuż przed wschodami - herbicyd Sencor 70 WG w ilości 1,0 kg·ha⁻¹. W największym stopniu cechy wydajności jednostkowej skorelowane były z powietrzne suchą masą chwastów oznaczoną pod koniec wegetacji.
Natural supplementations are used in agriculture nowadays not only for improving plant performance but also for reducing the contamination of plant edible parts. Two field trials were conducted to study the potential effects of licorice root extract (LRE; 0.5%) on performance, physio-biochemical components, antioxidant defense system, and contaminants concentrations of Capsicum annuum L. plants grown on a saline soil contaminated with heavy metals. LRE was applied in single (i.e., as rhizosphere application with drip irrigation water; -RA or as foliar spray; -FA) or in integration (i.e., LRE-RA + LRE-FA) treatment. The results showed that both single or integrative treatments significantly increased plant growth and yield, leaf concentrations of photosynthetic pigments, free proline, total soluble sugars, N, P, and K⁺, ratio of K⁺/Na⁺, and activities of CAT, POX, APX, SOD and GR, while significantly reduced contaminants; Na⁺, Cd, Cu, Pb and Ni concentrations in plant leaves and fruits on heavy metals-contaminated saline soil compared to the control (without LRE). Additionally, the integrative LRE-RA + LRE-FA treatment significantly exceeded both single treatments in this concern, which had been recommended for maximizing pepper plant performances with minimizing heavy metals in fruits on contaminated saline soils.
Nutrients availability and hydrological conditions of selected wetland ecosystems in the Biebrza river valley. Paper presents results of investigation of hydrological conditions and nutrients limitation and availability for wetland vegetation in selected sites within Biebrza river valley. Analysed sites were overgrown by tall sedge Magnocaricion vegetation (Caricetum gracilis and Caricetum elatae), wet meadow Molinio-Arrhenatheretea vegetation (Molinietum caeruleae), and sedge-moss Scheuchzerio-Caricetea nigrae vegetation (Caricetum lasiocarpae). There were noted a close relationship between vegetation types, hydrological regimes and kind of nutrient limitation. Low productive Molinio-Arrhenatheretea and Scheuchzerio-Caricetea nigrae vegetations fed mainly by groundwater were limited by phosphorus, while highly productive Magnocaricion vegetation, fed by river water, was subjected to nitrogen limitation. We have found big diversifi cation of groundwater and surface water levels within habitats of different vegetation types along the Biebrza river valley. Magnocaricion vegetation present on fl ooded areas is characterized by signifi cant water level fl uctuations and long-lasting inundations. On areas covered by Molinio- -Arrhenatheretea vegetation we noted majority of water levels not exceeding the level of the ground surface. Whereas Scheuchzerio-Caricetea nigrae vegetation, fed by groundwater, is characterized by low variation of groundwater levels.
In this study, the correlation coefficients among agro-morphological variation, genetic diversity, and drought tolerance in 44 rice cultivars were analyzed. The drought tolerance at seeding stage (DTS) was significantly proportional to drought tolerance at vegetative stage (DTV) (r = 0.60). In addition, DTS and DTV had strong significant positive correlation to leaf roll (r = 0.87 and 0.54, respectively). Means of unfilled grains and tilling per panicle were proportionally correlated to DTS (r = 0.22 and 0.25, respectively), and DTV (r = 0.20 and 0.36, respectively). However, weight of 1000 grains and filled grains were recorded no correlation to DTS and DTV. At a homologous coefficient of 16.85 integrated from cluster analysis of agro-morphological, quantitative characteristics and drought tolerant scores, the rice cultivars were divided into five groups. Maximum polymorphic information content (PIC) values were detected in three markers including RM11125, RM21, and RM5629, which were from 0.78 to 0.79. Cluster analysis of microsatellite markers revealed that by a genetic distance of 0.63, the rice varieties were separated into three clusters. The results provide valuable information for rice breeders to select donors in breeding rice integrated with drought tolerance and good agronomic characteristics.
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