scholarly journals Monitoring and evaluation of need for nitrogen fertilizer topdressing for maize leaf chlorophyll readings and the relationship with grain yield

2011 ◽  
Vol 54 (4) ◽  
pp. 665-674 ◽  
Author(s):  
Maria Anita Gonçalves da Silva ◽  
Antonio Saraiva Muniz ◽  
Anny Rosi Mannigel ◽  
Simone Maria Altoé Porto ◽  
Marlene Estevão Marchetti ◽  
...  
Keyword(s):  
Grain Yield ◽  
Nitrogen Fertilizer ◽  
Monitoring And Evaluation ◽  
Maize Leaf ◽  
Leaf Chlorophyll ◽  
The Relationship

IMPROVEMENT OF SPRING DURUM WHEAT SELECTION METHODOLOGIES UNDER CLIMATE CHANGE CONDITIONS

1970 ◽  
pp. 33-36
Author(s):  
А. I. Grabovets ◽  
V. P. Kadushkina ◽  
S. А. Kovalenko
Keyword(s):  
Grain Yield ◽  
Durum Wheat ◽  
Correlation Coefficient ◽  
Harvest Index ◽  
Unit Area ◽  
Correlation Coefficients ◽  
Chemical Mutagenesis ◽  
Main Method ◽  
The Relationship ◽  
Selection Of

With the growing aridity of the climate on the Don, it became necessary to improve the methodology for conducting the  breeding of spring durum wheat. The main method of obtaining the source material remains intraspecific step hybridization. Crossings were performed between genetically distant forms, differing in origin and required traits and properties. The use of chemical mutagenesis was a productive way to change the heredity of genotypes in terms of drought tolerance. When breeding for productivity, both in dry years of research and in favorable years, the most objective markers were identified — the size of the aerial mass, the mass of grain per plant, spike, and harvest index. The magnitude of the correlation coefficients between the yield per unit area and the elements of its structure is established. It was most closely associated with them in dry years, while in wet years it decreased. Power the correlation of the characteristics of the pair - the grain yield per square meter - the aboveground biomass averaged r = 0.73, and in dry years it was higher (0.91) than in favorable ones (0.61 - 0.70) , between the harvest and the harvest index - r = 0.81 (on average). In dry years, the correlation coefficient increased to 0.92. Research data confirms the greatest importance of the mass of grain from one ear and the plant in the formation of grain yield per unit area in both dry and wet years. In dry years, the correlation coefficient between yield and grain mass per plant was on average r = 0.80; in favorable years, r = 0.69. The relationship between yield and grain mass from the ear was greater — r = 0.84 and r = 0.82, respectively. Consequently, the breeding significance of the aboveground mass and the productivity of the ear, as a criterion for the selection of the crop, especially increases in the dry years. They were basic in the selection.

scholarly journals Optimizing Grain Yield and Water Use Efficiency Based on the Relationship between Leaf Area Index and Evapotranspiration

Agriculture ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 313
Author(s):  
Guoqiang Zhang ◽  
Bo Ming ◽  
Dongping Shen ◽  
Ruizhi Xie ◽  
Peng Hou ◽  
...  
Keyword(s):  
Grain Yield ◽  
Water Use Efficiency ◽  
Leaf Area Index ◽  
Water Use ◽  
Plant Density ◽  
Maize Yield ◽  
Area Index ◽  
Irrigation Level ◽  
Use Efficiency ◽  
The Relationship

Achieving optimal balance between maize yield and water use efficiency is an important challenge for irrigation maize production in arid areas. In this study, we conducted an experiment in Xinjiang China in 2016 and 2017 to quantify the response of maize yield and water use to plant density and irrigation schedules. The treatments included four irrigation levels: 360 (W1), 480 (W2), 600 (W3), and 720 mm (W4), and five plant densities: 7.5 (D1), 9.0 (D2), 10.5 (D3), 12.0 (D4), and 13.5 plants m−2 (D5). The results showed that increasing the plant density and the irrigation level could both significantly increase the leaf area index (LAI). However, LAI expansion significantly increased evapotranspiration (ETa) under irrigation. The combination of irrigation level 600 mm (W3) and plant density 12.0 plants m−2 (D4) produced the highest maize yield (21.0–21.2 t ha−1), ETa (784.1–797.8 mm), and water use efficiency (WUE) (2.64–2.70 kg m−3), with an LAI of 8.5–8.7 at the silking stage. The relationship between LAI and grain yield and evapotranspiration were quantified, and, based on this, the relationship between water use and maize productivity was analyzed. Moreover, the optimal LAI was established to determine the reasonable irrigation level and coordinate the relationship between the increase in grain yield and the decrease in water use efficiency.

Effects of Elevated Atmospheric CO2 and its Interaction with Temperature and Nitrogen on Yield of Barley (Hordeum vulgare L.): A Meta-analysis

2021 ◽  
Author(s):  
Mekides Woldegiorgis Gardi ◽  
Bettina I.G Haussmann ◽  
Waqas Ahmed Malik ◽  
Petra Högy
Keyword(s):  
Grain Yield ◽  
Nitrogen Fertilizer ◽  
Meta Analysis ◽  
N Fertilization ◽  
Additional Stress ◽  
Hordeum Vulgare L ◽  
Grain Number ◽  
Experimental Conditions ◽  
Elevated Atmospheric Co2 ◽  
The Mean

Abstract AimsThe general aim of this meta-analysis is to synthesize and summarise the mean response of barley yield variables to elevated CO2 (eCO2) and its interaction with temperature and N fertilization. Methods The present study quantitatively synthesized the response of barley to eCO2 and its interaction with temperature, and Nitrogen (N). A meta-analysis procedure was used to analyse five yield variables of barley extracted from 76 articles to determine the effect size and the magnitude in relation to eCO2 and its interaction with temperature and N. Results CO2 enrichment increased biomass (23.8%), grain number (24.8%), grain yield (27.4%), and thousand-grain weight (5.6%). However, responses to eCO2 were affected by genotype, additional stress, and experimental conditions. In comparison, genotype “Anakin” shows the highest response of biomass (47.1%), while “Genebank accessions” had a higher grain number (46.1%) and grain yield (57.1%) under eCO2. The maximal enhancement of barley yield was observed when plants grow under a combination of eCO2 and higher nitrogen fertilizer (>100 kg ha-1). Nevertheless, biomass (-12%), and grain yield (-17%) responses were lower when eCO2 is combined with high temperature (>25 °C). It was further noted the response of barley yield to eCO2 was higher in the growth chamber than in other CO2 exposure methods. Moreover, comparing pot-rooted versus field-rooted barley plants, a higher response of biomass and grain yield was observed for pot-rooted plants. ConclusionsOverall, results suggest that the maximal barley production under eCO2 will be obtained in combination with high nitrogen fertilizer and optimal temperature (21-25 °C).

Starter Nitrogen Fertilizer Affects Rice Growth and Nitrogen Uptake but Not Grain Yield

cftm ◽  
2018 ◽  
Vol 4 (1) ◽  
pp. 1-5
Author(s):  
Jason M. Satterfield ◽  
Gurpreet Kaur ◽  
Bobby R. Golden ◽  
John M. Orlowski ◽  
Timothy W. Walker
Keyword(s):  
Grain Yield ◽  
Nitrogen Uptake ◽  
Nitrogen Fertilizer ◽  
Rice Growth

scholarly journals Replacing Synthetic Nitrogen Fertilizer with Different Types of Organic Materials Improves Grain Yield in China: A Meta-Analysis

Agronomy ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 2429
Author(s):  
Xiaoru Fan ◽  
Zekai Chen ◽  
Zihan Niu ◽  
Ruiyao Zeng ◽  
Jingmin Ou ◽  
...  
Keyword(s):  
Grain Yield ◽  
Nitrogen Fertilizer ◽  
Organic Materials ◽  
Crop Yields ◽  
Meta Analysis ◽  
Chicken Manure ◽  
Agricultural Practice ◽  
Different Types ◽  
Synthetic Nitrogen Fertilizer

Synthetic nitrogen fertilizer substitution (NSS) with different types of organic material is a cleaner agricultural practice for reducing the application of synthetic N input in farmlands while also relieving the environmental issues caused by the discharge of organic wastes. However, the effects of the NSS practice on crop yields, being the primary objective of agricultural activity, is still uncertain in China. This study conducted a meta-analysis to assess the impacts of the NSS practices with different types of organic materials on crop yields. Results showed that the average crop yield was increased by 3.4%, with significant differences under NSS, thereby demonstrating that this practice contributed to improving crop yields, especially of rice and maize. According to published reports, the NSS practices involving chicken manure, pig manure, and crop straw increased crop yields by 4.79, 7.68, and 3.28%, respectively, with significant differences, thus demonstrating the superior effects needed for replacing synthetic N fertilizer. Moreover, substitution ratios (SR) between 0% and 60% could be suggested when using the NSS practice, with the high SR recommended when the original soil fertility was adequate for crops. Considering the long-term effects of applied organic materials, improving the grain yield with the NSS practice should be expected in the long-term. By effectively applying the NSS, this study attempted to scientifically decide on the type of organic materials and the appropriate SR based on the conditions of the soil and the crop. The results provide research information for the development of clean agricultural production and food security in China.

scholarly journals Monitoring and Evaluation Practices and Performance of County Maternal Health Programmes

2021 ◽  
Vol 17 (37) ◽  
pp. 39
Author(s):  
John Gatimu ◽  
Christopher Gakuu ◽  
Anne Ndiritu
Keyword(s):  
Maternal Health ◽  
Capacity Building ◽  
Health Sector ◽  
Monitoring And Evaluation ◽  
Evaluation Practices ◽  
Health Sector Reforms ◽  
And Performance ◽  
Descriptive Survey ◽  
The Relationship ◽  
Health Programmes

The study sought to establish the relationship between monitoring and evaluation practices and performance of County Maternal Health programmes in Kenya. The combined monitoring and evaluation practices included planning for M&E, stakeholder engagement, capacity building for M&E, and M&E data use. The study adopted a descriptive survey research design. To obtain 282 respondents, stratified random sampling was used. A self-administered structured questionnaire was the study's research instrument. Using descriptive narratives, qualitative data was analyzed within specific themes. Quantitative data was analyzed descriptively using measures of central tendencies and measures of dispersion. Regression was conducted for testing the study hypotheses. Data was presented using frequency tables. The study found that stakeholders’ engagement in M&E and capacity building for M&E influenced the performance of County Maternal Health Programmes in Kenya. The study also found that the respondents agreed that planning for M&E and the data management for M&E. This implied that the combined monitoring and evaluation practices influence performance of County Maternal Health Programmes in Kenya.The study found a strong correlation between the performance of county maternal health programmes and combined monitoring and evaluation practices. The study concluded that combined planning for M&E monitoring and evaluation practices influenced the performance of county maternal health programmes. The study suggests that management develop an effective methodology as well as raise awareness of M&E activities for the success of the project. The study also suggests that human resources issues such as workers charged with monitoring and evaluation ought to have technical capabilities, and roles and duties of monitoring and evaluation personnel should be outlined at the start of projects. To ensure M&E sustainability health sector reforms, investments in strong and vibrant technical harmonization platforms that can sustain the change agenda at all times and every required level.

THE RELATIONSHIP BETWEEN FINAL YIELD AND PHOTOSYNTHESIS AT FLOWERING IN INDIVIDUAL MAIZE PLANTS

1979 ◽  
Vol 59 (3) ◽  
pp. 585-601 ◽  
Author(s):  
G. O. EDMEADES ◽  
T. B. DAYNARD
Keyword(s):  
Grain Yield ◽  
Shoot Growth ◽  
Plant Density ◽  
Meteorological Data ◽  
Dry Weight ◽  
Plant Variation ◽  
Final Yield ◽  
Black Layer ◽  
Maize Plants ◽  
The Relationship

In an attempt to explain plant-to-plant variation in dry weight of maize (Zea mays L.), a computer program was developed to predict daily assimilation per plant and its distribution throughout the shoot at flowering. Inputs to the model were meteorological data, photosynthetic rate-irradiance curves, measurements of intraplant assimilate distribution at flowering, and the positions of individual leaves of plants grown in the field at three densities (50 000, 100 000 and 150 000 plants/ha). Dry weights were recorded on these same plants following black layer formation. Predicted effects of plant density on shoot growth compared favorably with available data. The correlation coefficient between predicted assimilation 1 day after anthesis and grain yield on the same plants, with treatment effects removed, was 0.67 (N = 360). The coefficient of variation of predicted assimilate flux per plant increased significantly with increasing density, and the fluxes were generally normally distributed. Results supported the concept of a threshold assimilation rate per plant below which grain would not normally form, and this appears to be the cause of the bimodal frequency distribution of grain yield per plant observed at high densities.

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