Genetic Gain in Wheat Grain Yield and Nitrogen Use Efficiency at Different Nitrogen Levels in an Irrigated Hot Environment

Improved nitrogen use-efficient cultivars could be the most economically beneficial and environmentally friendly approach to reduce pollution associated with excessive N fertilization. The performance and genetic gain in grain yield and nitrogen use efficiency (NUE) of a historical set of 12 bread wheat cultivars released for a heat-stressed environment were investigated at four N levels (0 (N0), 43 (N43), 86 (N86), and 129 (N129) kg/ha) for two seasons. Averaged across seasons, increasing N level from N0 to N43, N86, and N129 resulted in yield increases ranging from 4−45%, 13–69%, and 34–87% at N43, N86, and N129, respectively. These yield increases were associated with increases in biomass (r = 0.86, P<0.01). Regressing grain yield of cultivars released during 1960 to 2006 against the year of release showed no trend at N0 and positive nonsignificant trends at N43;. however, significant positive trends were found at N86 and N129 with genetic gain rates of 12.65 and 15.76 kg ha−1 year−1, respectively. This gain was associated with progresses in harvest index (HI) at N43, N86, and N129 but not at N0. On the other hand, during the period from 1960 to 1990, the genetic gain in grain yield at N86 was 24.5 kg ha−1 year−1. Regressing NUE against the year of release showed significant linear trends at N86 and N129 (R2 = 0.511 and R2 = 0.477, respectively), but not at N43. The results indicate that breeders improved grain yield and NUE over 46 years under the heat-stressed environment of Sudan although the rate of increase in yield has been slowed down in recent years. Further improvement in NUE might require broadening the genetic diversity and simultaneous evaluation at low and high N levels.

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Roles of Nitrogen Deep Placement on Grain Yield, Nitrogen Use Efficiency, and Antioxidant Enzyme Activities in Mechanical Pot-Seedling Transplanting Rice

Agronomy ◽

10.3390/agronomy10091252 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1252

Author(s):

Lin Li ◽

Zheng Zhang ◽

Hua Tian ◽

Zhaowen Mo ◽

Umair Ashraf ◽

...

Keyword(s):

Grain Yield ◽

Antioxidant Enzyme ◽

Nitrogen Use Efficiency ◽

Enzyme Activities ◽

N Fertilization ◽

Antioxidant Enzyme Activities ◽

Nitrogen Accumulation ◽

Nitrogen Use ◽

Deep Placement ◽

Use Efficiency

Mechanical pot-seedling transplanting (PST) is an efficient transplanting method and deep nitrogen fertilization has the advantage of increasing nitrogen use efficiency. However, little information is available about the effect of PST when coupled with mechanized deep nitrogen (N) fertilization on grain yield, nitrogen use efficiency, and antioxidant enzyme activities in rice. A two-year field experiment was performed to evaluate the effect of PST coupled with deep N fertilization in both early seasons (March–July) of 2018 and 2019. All seedlings were transplanted by PST and three treatments were designed as follows. There was a mechanized deep placement of all fertilizer (MAF), broadcasting fertilizer (BF), no fertilizer (N0). MAF significantly increased grain yield by 52.7%. Total nitrogen accumulation (TNA) was enhanced by 27.7%, nitrogen partial factor productivity (NPFP) was enhanced by 51.4%. nitrogen recovery efficiency (NRE) by 123.7%, and nitrogen agronomic efficiency (NAE) was enhanced by 104.3%, compared with BF treatment. Moreover, MAF significantly improved peroxidase (POD), catalase (CAT), and notably reduced the malonic dialdehyde (MDA) content for both rice cultivars, compared to BF. Hence, the result shows that mechanical pot-seedling transplanting coupled with nitrogen deep placement is an efficient method with the increase of grain yield and nitrogen use efficiency in rice cultivation in South China.

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Grain yield, nitrogen-use efficiency and baking quality of old and modern Italian bread-wheat cultivars grown at different nitrogen levels

European Journal of Agronomy ◽

10.1016/j.eja.2003.08.001 ◽

2004 ◽

Vol 21 (2) ◽

pp. 181-192 ◽

Cited By ~ 195

Author(s):

Giovanni Guarda ◽

Silvano Padovan ◽

Giovanni Delogu

Keyword(s):

Grain Yield ◽

Bread Wheat ◽

Nitrogen Use Efficiency ◽

Wheat Cultivars ◽

Nitrogen Use ◽

Baking Quality ◽

Nitrogen Levels ◽

Use Efficiency

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Effect of Long-Term Nitrogen Addition on Wheat Yield, Nitrogen Use Efficiency, and Residual Soil Nitrate in a Semiarid Area of the Loess Plateau of China

Sustainability ◽

10.3390/su12051735 ◽

2020 ◽

Vol 12 (5) ◽

pp. 1735 ◽

Cited By ~ 8

Author(s):

Aixia Xu ◽

Lingling Li ◽

Junhong Xie ◽

Xingzheng Wang ◽

Jeffrey A. Coulter ◽

...

Keyword(s):

Grain Yield ◽

Loess Plateau ◽

Nitrogen Use Efficiency ◽

Wheat Yield ◽

N Fertilization ◽

N Fertilizer ◽

Residual Soil ◽

Nitrogen Use ◽

N Application ◽

Use Efficiency

Nitrogen (N) fertilizer plays an important role in wheat yield, but N application rates vary greatly, and there is a lack of data to quantify the residual effects of N fertilization on soil N availability. A 17-yr experiment was conducted in a semiarid area of the Loess Plateau of China to assess the effects of N fertilization on spring wheat (Triticum aestivum L.) grain yield, N uptake, N utilization efficiency, and residual soil nitrate. Treatments included a non-N-fertilized control and annual application of 52.5, 105.0, 157.5, and 210.0 kg N ha−1 in the first two years (2003 and 2004). In the third year (2005), the four main plots with N fertilizer application were split. In one subplot, N fertilization was continued as mentioned previously, while in the other subplot, N fertilization was stopped. The concentration of NO3-N in the 0–110 cm depth soil layers was significantly affected by N application, with higher N rates associated with greater soil NO3-N concentration. With the annual application of N over 17 years, residual soil NO3-N concentration in the 100–200 cm soil layer in the last study year was significantly greater than that in the non-N-fertilized control and was increased with rate of N application. There was a significant positive relationship of soil NO3-N in the 0–50 cm and 50–110 cm soil layers at wheat sowing with wheat grain N content and yield. Wheat grain yield in the third year (2005) was significantly, i.e., 22.57–59.53%, greater than the unfertilized treatment after the N application was stopped. Nitrogen use efficiency decreased in response to each increment of added N fertilizer, and was directly related to N harvest index and grain yield. Therefore, greater utilization of residual soil N through appropriate N fertilizer rates could enhance nitrogen use efficiency while reducing the cost of crop production and risk of N losses to the environment. For these concerns, optimum N fertilizer application rate for spring wheat in semiarid Loess Plateau is about 105 kg N ha−1, which is below the threshold value of 170 kg N ha−1 per year as defined by most EU countries.

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Grain yield and nitrogen use efficiency of various modern rice cultivars grown at different nitrogen levels

Journal of Plant Nutrition ◽

10.1080/01904167.2016.1264421 ◽

2017 ◽

Vol 40 (8) ◽

pp. 1125-1132 ◽

Cited By ~ 3

Author(s):

Xiaokun Li ◽

Zhengwei Xu ◽

Chen Guo ◽

Tao Ren ◽

Rihuan Cong ◽

...

Keyword(s):

Grain Yield ◽

Nitrogen Use Efficiency ◽

Rice Cultivars ◽

Nitrogen Use ◽

Nitrogen Levels ◽

Use Efficiency

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Effects of Nitrogen Levels on Growth, Yield And Nitrogen use Efficiency Of Some Newly Released Egyptian Rice Genotypes

Open Agriculture ◽

10.1515/opag-2018-0034 ◽

2018 ◽

Vol 3 (1) ◽

pp. 310-318 ◽

Cited By ~ 9

Author(s):

Adel M. Ghoneim ◽

Gewaily E.E. ◽

Marvet M.A. Osman

Keyword(s):

Grain Yield ◽

Nitrogen Use Efficiency ◽

Nitrogen Fertilizer ◽

Growth And Yield ◽

Rice Varieties ◽

Nitrogen Use ◽

Nitrogen Levels ◽

Growing Seasons ◽

Use Efficiency ◽

Rice Genotypes

Abstract Application of appropriate level of nitrogen fertilization is a major objective to increase nitrogen use efficiency by rice varieties. Field experiments were conducted during 2016 and 2017 growing seasons to evaluate the efficiency of varying nitrogen fertilizer rates on growth and yield parameters, along with nitrogen use efficiency of some newly released rice varieties (Sakha 108) and some promising lines GZ9399-4-1-1-3-2-2, GZ10101- 5-1-1-1 and GZ10154-3-1-1-1. Five nitrogen levels (i.e. 0, 55, 110, 165 and 220 kg N ha-1) were used. The results from both growing seasons indicated that, Sakha 108 recorded the highest grain yield while GZ10154 and GZ10101 recorded the lowest grain yields. A linear increase in grain yield was observed with continuous rate increase of nitrogen from 0 to 220 kg ha-1, while 220 kg N ha-1 treatment showed maximum grain yield followed by 165 kg N ha-1, with control as minimum. Agronomic nitrogen use efficiency (AE) for studied rice genotypes varied significantly, and ranged from 3.63 to 32.9 and from 2.72 to 34.12 kg grain yield produced per kg of nitrogen applied in 2016 and 2017 respectively. Across N levels, GZ9399 recorded the highest values of AE for the nitrogen fertilizer rate of 165 kg N ha-1 in both seasons.

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