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1.
Field experiment was conducted to investigate the impact of phosphorus (P) and beneficial microorganism (BM) on the yield and yield components wheat (Triticum aestivum L., cv. Siren-2010). The experiment was conducted under full (five irrigations) and limited (two) irrigation conditions at the Research Farm of The University of Agriculture Peshawar during winter 2012–13. The experiment under both full and limited irrigated conditions was laid out in randomized complete block design using three replications. The results showed that irrigated plots produced more spikes m?2 (254), grains spike?1 (55.5), heavier thousand grains weight (39.4 g), and higher grain yield (3612 kg ha?1 than limited irrigated condition. Application of P at the highest rate (90 kg P ha?1) produced more spikes m?2 (260) and grains spike?1 (52.4), and increased maximum thousand grain weight (39.1 g) and grain yield (3617 kg ha?1). Application of BM at the highest rate (30 L ha?1) resulted in maximum number of spikes m?2 (257) and grains spike?1(51.7), highest thousand grains weight (39.1 g) and grain yield (3765 kg ha?1). The results confirmed that under full irrigated condition the increase in both P and BM levels (90 kg P ha?1 and 30 L ha?1, respectively) and under limited irrigated condition the intermediate levels of both P and BM (60 kg P ha?1 and 20 L ha?1, respectively) could increase wheat productivity under semi-arid conditions.  相似文献   

2.
Information on the combined use of organic and inorganic fertilizers on wheat (Triticum aestivum L.) productivity is lacking under moisture stress conditions of Northwest Pakistan. The present experiment was designed to ascertain the combined effect of organic and inorganic fertilizer management on rainfed wheat. Four levels of farm yard manure, FYM, (0, 10, 20, and 30 Mg FYM ha?1) and nitrogen (0, 30, 60, 90, and 120 kg N ha?1) were used. The experiment was conducted at the Agriculture Research Farm of NWFP Agricultural University Peshawar, Pakistan during crop season of 2003–04. The experiment was laid out in randomized complete block design with four replications. Plant height, productive tillers m?2, grains spike?1, grain yield, straw yield, and harvest index were significantly higher in plots which received 30 Mg FYM ha?1. In the case of nitrogen (N) no distinctive differences between the effect of 90 and 120 kg ha?1 was observed for most of the parameters. Nitrogen application at 90 kg ha?1 had significantly higher; plant height, grains spike?1, grain yield, straw yield, and harvest index as compared with the lower levels, i.e., 0, 30, and 60 kg N ha?1 but were at par with 120 N kg ha?1. Significantly higher numbers of productive tillers m?2, grains spike?1, grain yield, straw yield and harvest index were recorded with application of 30 Mg FYM ha?1 + 90 kg N ha?1. The present study suggested that application of 30 Mg FYM ha?1 + 90 kg N ha?1 are promising levels for higher production of wheat under moisture stress conditions. Further research work is needed to ascertain the effect of N above 90 kg ha?1 under different moisture regimes.  相似文献   

3.
The permanent bed planting system for wheat (Triticum aestivum L.) production has recently received additional attention. Studies using hard red spring wheat (cultivar Nahuatl F2000) were conducted at two locations in central Mexico. The studies included the installation of three furrow diking treatments, two granular N timing treatments and three foliar N rates applied at the end of anthesis. The objective was to evaluate the effect of these factors on wheat grain yield, yield components and grain N in a wheat–maize (Zea maize L.) rotation with residues of both crops left as stubble. Results indicated that diking in alternate furrows increased both grain yield and the final number of spikes per m2. The split application of N fertilizer enhanced the number of spikes per m2 and grain N uptake, but the effect on grain yield was inconsistent. Similarly, grain protein increased with the foliar application of 6 kg N ha?1, depending upon the maximum temperature within the 10 days following anthesis. The normalized difference vegetative index (NDVI) readings collected at four growth stages were generally higher for the split N application than for the basal N application at planting. Grain N uptake was associated to NDVI readings collected after anthesis.  相似文献   

4.
施氮与灌水对夏玉米产量和水氮利用的影响   总被引：7，自引：3，他引：7  
通过田间裂区试验,研究了不同灌水量（900、 1200和1500 m3/hm2）和施氮量（0、 150、 210和270 kg/hm2）对夏玉米生长状况、 产量构成及水、 氮利用效率等的影响。结果表明: 当灌水量超过最低量 900 m3/hm2、 施氮量超过150 kg/hm2时,二者对玉米产量、 产量构成因素（穗粒数、 百粒重及穗粒重）和收获指数（HI）以及各生育期干物质积累量等均没有明显影响; 氮肥农学效率和氮肥偏生产力随氮肥用量的增加呈明显降低趋势; 灌水生产效率和水分利用效率随灌水量的增加也显著降低,二者均表现为900 m3/hm21200 m3/hm21500 m3/hm2。因此,在本试验条件下,以W900N150处理的水、 氮利用效率、 产量及其构成因素等较高,并且对环境造成潜在危害最小,为当地地域气候条件下夏玉米生产中节水减氮的较为适宜的水氮配比。  相似文献   

5.
Zinc (Zn) deficiency caused by inadequate dietary intake is a global nutritional problem, so increasing Zn concentrations in crops is a challenging and high-priority research task. A field experiment was conducted to explore the effects of nitrogen (N) fertilizers on Zn absorption and translocation in winter wheat during the 2010–2011 and 2011–2012 crop seasons, in Xinzheng City, Henan Province, China. N was applied at four levels (0, 90, 180, and 270 kg N ha?1) and Zn was applied at two levels (15 and 30 kg zinc sulfate heptahydrate (ZnSO4·7H2O) ha?1]. The results indicated that reasonable N application increased grain yield, total Zn accumulations, and Zn concentrations of each plant part of winter wheat. Furthermore, appropriate N application increased Zn distribution proportions in grains and decreased Zn distribution proportions in roots, stems, leaves, and spikes, and enhanced Zn removal from roots, stems, leaves, and spikes to grains. Meanwhile, reasonable N combined with higher Zn application had a better effect on Zn absorption and Zn translocation to grain of winter wheat. The results suggested that suitable quantity of N fertilizer combined with higher Zn application is an important measure to obtain both higher grain yield and grain Zn concentration in winter wheat production.  相似文献   

6.
Spring-sown crops are expected to have a higher risk of drought during summer in the next decades in Central Europe due to expected climate change. Therefore, a two-year experiment was conducted under Pannonian growing conditions in Eastern Austria to investigate the effect of autumn- and spring-sowing of facultative wheat. Autumn-sowing of facultative wheat enhanced crop development, soil coverage, crop stand height, crop growth rate, and nitrogen (N) utilization efficiency during the vegetation period compared to spring-sowing; duration of growth stages was prolonged and crops were earlier ripe. In contrast, spring-sowing resulted in higher relative growth rates, higher N concentrations of aboveground dry matter, higher relative N uptake rates, and more mineral N in the soil. At harvest, grain yield and yield components ears m?2 and thousand kernel weight (TKW) were higher in autumn-sown than in spring-sown wheat, resulting thereby in an increased seed yield. Spring-sown wheat had higher N concentrations in grain and in straw. Anyhow, N yield was slightly higher with autumn-sowing due to the higher grain and straw yields. Grain and straw yield, plant stand height, ears m?2, and TKW were impaired in the second experimental year by a severe drought for both sowing dates as well as N concentrations and N yields of grain and straw, partial factor N use efficiency and N utilization efficiency. But the yield components harvest index, grains m?2, and grains ear?1 were strongly impaired with spring-sowing under drought conditions. Thus, autumn-sowing of wheat resulted in higher yield stability across both years, based on these yield components highlighting possible benefits of autumn-sowing with expected summer drought under climate change.  相似文献   

7.
Increased application of nitrogen fertilizers has significantly raised grain yield and protein concentration in wheat. However, only 30–50% of applied fertilizer nitrogen are usually utilized by the plant. In this study, four soft red winter wheat genotypes (Triticum aestivum L., IL07‐4415, MD05W10208‐11‐8, OH06‐150‐57 and Sisson) were grown under three different nitrogen regimes (high, medium, and low) in a greenhouse, and grain yield, grain protein concentration, nitrogen use efficiency (NUE) and their associated traits were evaluated. Among the four genotypes, a high‐yielding cultivar, Sisson, exhibited superior performance in terms of grain weight plant−1 and NUE for yield (NUEY) at low nitrogen due to maintained grain number spike−1 and harvest index. Significant yield losses due to nitrogen limitation were attributable to reduced spike number plant−1 and grain number spike−1 in the other genotypes. Interestingly, a linear relationship between NUEY and NUE for grain protein (NUEP) was detected at high (R 2 = 0.67) and low (R 2 = 0.42) nitrogen; both of these traits were positively correlated with grain number spike−1, 1000‐seed weight, and harvest index under nitrogen‐limited conditions (R 2 = 0.35–0.48). These results suggest that simultaneous improvement of NUEY and NUEP could be achieved through the selection of the three yield components (grain number spike−1, 1000‐seed weight, and harvest index) at low nitrogen.  相似文献   

8.
Introducing autumn-sown legumes into Central European farming systems could be beneficial for addressing two challenges for European agriculture, i.e., the substantial deficit of protein sources for livestock and expected changes in agroclimatic conditions. Therefore, a two-year field experiment was conucted under Pannonian climate conditions in eastern Austria to assess nitrogen (N) yield and N fixation of several winter faba bean varieties from different European countries as compared to a spring faba bean. Winter wheat was used as a reference crop for estimating atmospheric N fixation. Winter faba beans were susceptible to frost damage especially in the harder of the two winters. Winter faba bean varieties could not achieve a higher grain yield and a higher grain N yield than the spring faba bean but had a higher grain N concentration (except for one variety). Grain yield and grain N yield of faba beans were severely impaired by drought in one year (with a mean of varieties of 8.3 g N m?2, winter wheat: 6.4 g N m?2); in the other year, grain N yield of faba beans considerably surpassed that of winter wheat (with a mean of varieties of 21.5 g N m?2, winter wheat: 8.8 g N m?2). After harvest, faba beans left higher nitrate residues in the soil, especially in the subsoil, and higher amounts of N in above-ground residues compared to winter wheat. Faba beans showed high N fixation under optimum conditions (with a mean of varieties of 21.9 g N m?2) whereas drought considerably impaired N fixation (with a mean of varieties of 6.3 g N m?2; with no differences between autumn- and spring-sown faba beans). In conclusion, growing winter faba bean varieties in eastern Austria did not result in higher grain yield, grain N yield, and N fixation compared to growing a spring faba bean.  相似文献   

9.
Dry bean (Phaseolus vulgaris L.) is an important legume worldwide and nitrogen (N) is most yield limiting nutrients. A field experiment was conducted for two consecutive years to evaluate response of 15 dry bean genotypes to nitrogen and rhizobial inoculation. The N and rhizobia treatments were (i) control (0 kg N ha?1), (ii) seed inoculation with rhizobia strains, (iii) seed inoculation with rhizobia strains + 50 kg N ha?1, and (iv) 120 kg N ha?1. Straw yield, grain yield, and yield components were significantly influenced by N and rhizobial treatments. Grain yield, straw yield, number of pods m?2, and grain harvest index were significantly influenced by year, nitrogen + rhizobium, and genotype treatments. Year × Nitrogen + rhizobium × genotype interactions were also significant for these traits. Hence, these traits varied among genotypes with the variation in year and nitrogen + rhizobium treatments. Inoculation with rhizobium alone did not produce maximum yield and fertilizer N is required in combination with inoculation. Based on grain yield efficiency index, genotypes were classified as efficient, moderately efficient, and inefficient in nitrogen use efficiency (NUE). NUE defined as grain produced per unit N applied decreased with increasing N rate. Overall, NUE was 23.17 kg grain yield kg?1 N applied at 50 kg N ha?1 and 13.33 kg grain per kg N applied at 120 kg N ha?1.  相似文献   

10.
ABSTRACT

Corn (Zea mays L.) production recommendations should be periodically evaluated to ensure that production practices remain in step with genetic improvements. Since most of the recent increases in corn grain yield are due to planting at higher densities and not to increased per-plant yield, this study was undertaken to measure the effects of plant density and hybrid on corn forage and grain yield and on nutrient uptake. Plant density (4.9, 6.2, 7.4, and 8.6 seeds m?2) and hybrid relative maturity (RM) [early (108 day RM); medium (114 day RM); and late (118 day RM)] combinations were evaluated over five site-years under irrigated and non-irrigated conditions. The interaction of hybrid with plant density was never significant for grain, stem, or leaf biomass. The latest RM hybrid out-yielded the medium and early hybrids by 550 and 1864 kg ha?1, respectively. Grain yield was highest at 8.6 plants m?2. Total stem yield was also greatest at the highest plant density but by only 340 kg ha?1 more than at 7.4 seeds m?2. Based on grain yield response over sites, the estimated optimum density was 7.6 seeds m?2, which is 0.7 seeds m?2 higher than the current recommendation at this average yield level (11.5 Mg ha?1). Grain nitrogen (N), phosphorus (P), and potassium (K) uptakes were highest for the medium RM hybrid. Nutrient uptake levels varied by planting density, with the lowest levels observed at the lowest and highest plant densities. At 4.9 seeds m?2, the reduced uptake is explained by lower biomass yields. At the 8.6 seeds m?2 rate, N and K levels may have been lower due to dilution.  相似文献   

11.
The effects of irrigation regimes (full irrigation and water-withholding at anthesis) and postanthesis nitrogen (N) supplies (LN, 0; MN 20; and HN, 40 kg N ha?1) on grain yield and its components in winter wheat were studied, with attention to biomass gain by assimilation and its loss by respiration. Fully irrigated wheat responded to N fertilization with increased grain number (GN) and decreased grain weight (GW), whereas drought-stressed wheat responded with greater GN without significant changes in GW. Apparent whole-plant respiration (RA) was not influenced by increased postanthesis N fertilizer. Thus, in drought-stressed wheat, the total biomass and stem reserves at maturity were increased by increasing N supply. These results suggest that high N supply at anthesis satisfied the grains’ increased demand for N by increasing postfloral assimilation, and the surplus assimilates not only compensated for the low-N-induced biomass loss by respiration but also may have increased the stem reserves.  相似文献   

12.
In order to evaluate irrigation regimes and nitrogen fertilization on quality characteristics of wheat cultivars, a field experiment was carried out using split-plot factorial design based on randomized complete block design with three replications in Quchan, Iran (2010–2012). Main plots were assigned with four irrigation regimes; I1, 90 mm; I2, 130 mm; I3, 170 mm based on evaporation from a class A pan; and I4, water deficit stress during post-anthesis stage; sub-plots were assigned with four levels of nitrogen (N1, 0; N2, 70; N3, 140; and N4, 210 kg ha?1); and three wheat cultivars (V1, Mihan; V2, C-87-6; and V3, C-87-11) were used as factorial. The results showed that nitrogen fertilization increased some quality characteristics. Under water deficit (I4), gluten index, grain protein content, grain yield, and sedimentation volume decreased. Significant interactions between irrigation regimes and both nitrogen levels and cultivars were observed.  相似文献   

13.
Appropriate nitrogen (N) management practices are of critical importance in improving N use efficiency (NUE), maize (Zea mays) yield and environmental quality. A six-year (2005–2010) on-farm trial was conducted in Ottawa, Canada to assess the effects of N rates and application methods on grain yield and NUE. In four out of the six-year study, grain yield increased by 60–77 kg ha?1 by sidedress, compared to 49–66 kg ha?1 for each kg N ha?1 applied at preplant. Grain yield response to N between the two strategies was similar in the other growing seasons. Sidedress strategy required 15 kg N ha?1 less of the maximum economic rate of N (MERN) than preplant application. Our results indicate that sidedress application of 90–120 kg N ha?1 with a starter of 30 kg N ha?1 resulted in greater yield, grain quality and NUE than preplant N application in this cool, humid and short growing-season region.  相似文献   

14.
Ammonium sulfate and urea are main sources of nitrogen (N) for annual crop production in developing countries. Two greenhouse experiments were conducted using ammonium sulfate and urea as N sources for upland rice grown on a Brazilian Oxisol. The N rates used were 0, 50, 100, 150, 3000, and 400 kg N kg?1 of soil. Yield and yield components were significantly increased in a quadratic fashion with increasing N rate. Ammonium sulfate X urea interaction was significant for grain yield, shoot dry matter yield, panicle number, plant height and root dry weight, indicating a different response magnitude of these plant parameters to two sources of N. Based on regression equation, maximum grain yield was achieved with the application of 380 mg N kg?1 by ammonium sulfate and 271 mg N kg?1 by urea. Grain yield and yield components were reduced at higher rates of urea (>300 mg kg N) but these plant parameters’ responses to ammonium sulfate at higher rates was constant. In the intermediate N rate range (125 to 275 mg kg?1), urea was slightly better compared to ammonium sulfate for grain yield. Grain yield was significantly related with plant height, shoot dry weight, panicle number, grain harvest index and root dry weight. Hence, improving these plant characteristics by using appropriate soil and plant management practices can improve upland rice yield.  相似文献   

15.
This research was carried out to determine the effects of rate and time of nitrogen (N) application on safflower in a calcareous soil. The nitrogen rates were 50, 75, 100, 125, and 150 kg ha?1 and three split application methods were used. Experimental treatments were conducted as a factorial in a randomized complete block design (RCBD) with three replications. Duncan's Multiple Range Test (DMRT) indicated that the three split application of 100 kg ha?1 of nitrogen in stages of sowing date, early stem elongation, and early flowering had higher grain yield (2627 kg ha?1) than other treatments. This result was forecasted by results of increases in number of heads per square meter (heads m?2), number of grains per head (grains/head), and thousand grain weight (TGW). The highest oil yield was 755 kg ha?1 with the 100 kg ha?1 nitrogen application and was 727 kg ha?1 in treatment of three split application.  相似文献   

16.
Nitrogen (N) is one of the most important impact factors on development and growth of wheat. In this study the effects of nitrogen use efficiency on quantity and quality of grains were studied by agronomic management of N fertilizers on spring wheat (Triticum aestivum L.) grown under field conditions for two years. The experiments were performed at 16 combinations of N application amount and time, including four levels of N at 0, 60, 120 and 180 kg N ha?1 that were used as pre-plant fertilizers, sub-treated with four levels of the same N amount used as top-dress fertilizers. As a result, with an increase in total N fertilizers, grain yield increased in a cubic equitation, but partial factor productivity (PFPN, kg grain yield per kg N applied) decreased exponentially. With total fertilizers, N content and accumulation in vegetative tissues and grains increased linearly, but N uptake efficiency (UtEN, kg nutrient taken up per kg N applied) decreased exponentially. When N was over-applied (>360 kg N ha?1 in this study), grain yield clearly declined, due to decrease in productivity from per unit N. The high N level (240～300 kg N ha?1), the reasonable distribution between pre-plant and top dress from the same amount N fertilizer not only increased grain yield but also enhanced N use efficiency.  相似文献   

17.
Poor soil fertility is a major constraint to crop productivity in the highlands of Ethiopia. This study was conducted to evaluate the effects of nitrogen (N) fertilization, variety and growing season on grain yield and yield related traits, and determine relationships among agronomic traits of malting barley. The treatments studied were five N levels (0, 23, 46, 69 and 92?kg ha?1) and two malting barley varieties (Miscal-21 and Holker) over three growing seasons (2012, 2013 and 2014) at Bekoji, south eastern Ethiopia. The results revealed that as N rates increased, grain yield, number of tillers and spikes per square meter, biomass yield at harvest, days to physiological maturity, spike length and number of kernels per spike increased, but harvest index decreased. Grain yield, harvest index, number of tillers and spikes per square meter, spike length and biomass yield at harvest were greater in Miscal-21, whilst days to maturity and number of kernels per spike were greater in Holker. Grain yield, harvest index, number of tillers and spikes per square meter, spike length, biomass yield at harvest and days to maturity were significantly affected by seasonal conditions, but spike length and kernels per spike were not affected. Grain yield was positively influenced by the number of tillers per square meter, biomass yield at harvest, spikes per square meter, spike length, kernels per spike and harvest index. However, the number of tillers per square meter followed by biomass yield and spikes per square meter largely determined grain yield. The results of the current study suggest that genetic improvement of those yield related traits is the likely basis of increasing grain yield in barley.  相似文献   

18.
ABSTRACT

Rice is a staple food for more than 50% of the world's population and nitrogen (N) is one of the most yield limiting nutrients in lowland rice ecosystems. A field experiment was conducted for two consecutive years to evaluate dry matter production and grain yield of 12 lowland rice genotypes (BRS Jaçanã, CNAi 8860, BRS Fronteira, CNAi 8879, CNAi 8880, CNAi 8886, CNAi 8885, CNAi 8569, BRSGO Guará, BRS Alvorada, BRS Jaburu, and BRS Biguá) at five N rates (0, 50, 100, 150, and 200 kg ha? 1). Genotypes showed significant variation in grain yield and shoot dry weight. Genotype BRSGO Guará was highest yielding, whereas genotype BRS Jaburu was lowest yielding and the remaining genotypes were intermediate in grain yielding potential. Grain yield and shoot dry weight were having significant quadratic increase with increasing N rates in the range of 0 to 200 kg ha? 1. However, 90% of the maximum yield is often considered as an economical rate, which was 120 kg for shoot dry weight and 136 kg N ha? 1 for grain yield. Shoot dry matter was having significant positive quadratic association with grain yield across 12 genotypes.  相似文献   

19.
A field experiment was conducted over two years to evaluate the gas exchange, water relations, and water use efficiency (WUE) of wheat under different water stress and nitrogen management practices at Crop Physiology Research Area, University of Agriculture, Faisalabad, Pakistan. Four irrigation regimes and four nitrogen levels, i.e., 0, 50, 100, and 150 kg N ha?1 were applied in this study. The photosynthetic gas exchange parameters [net carbon dioxide (CO2) assimilation rate, transpiration rate and stomatal conductance] are remarkably improved by water application and nitrogen (N) nutrition. Plants grown under four irrigation treatments as compared with those grown under one irrigation treatment average stomatal conductance increased from 0.15 to 0.46 μ mol m?2s?1mol during 2002–2003 and 0.18 to 0.33 μ mol m?2s?1mol during the year 2003–2004 and photosynthetic rate from 9.33 to 13.03 μmol CO2 m?2 s?1 and 3.99 to 7.75 μmol CO2 m?2 s?1 during the year 2002–2003 and 2003–2004, respectively. The exposure of plants to water and nitrogen stress lead to noticeable decrease in leaf water potential, osmotic potential and relative water content. Relative water content (RWC) of stressed plants dropped from 98 to 75% with the decrease in number of irrigation and nitrogen nutrition. The higher leaf water potential, and relative water contents were associated with higher photosynthetic rate. Water use efficiency (WUE) reduced with increasing number of irrigations and increased with increasing applied nitrogen at all irrigation levels.  相似文献   

20.
ABSTRACT

Nitrogen is one of the most yield–limiting nutrients in lowland rice in Brazil. A field experiment was conducted for two consecutive years to evaluate nitrogen (N) uptake by five lowland rice genotypes and its association with grain yield. The nitrogen rate used was 0, 50, 100, 150, and 200 kg ha?1. The genotypes evaluated were CNAi 8886, CNAi 8569, BRSGO Guará, BRS Jaburu, and BRS Biguá. Grain yield and dry matter yield of shoot were significantly influenced by N rate. However, response varied from genotypes to genotypes. Genotype BRSGO Guará, BRS Bigua, and BRS Jaburu were having linear response, whereas genotypes CNAi 8886 and CNAi 8569 were having quadratic response with the N application rate in the range of 0 to 200 kg ha?1. Overall, genotypes BRSGO Guará and CNAi 8886 were the best because they produced higher yield at low as well as at higher N rates. Nitrogen uptake in shoot was having quadratic relationship with grain yield, whereas nitrogen uptake in the grain was linearly associated with grain yield.  相似文献   

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