Average Maize Yield Research Articles

DETERMINING THE EFFICIENCY OF NITROGEN FERTILIZERS ON MAIZE USING ISOTOPE METHODS AT DIFFERENT IRRIGATION LEVELS

<p>The isotope technique can be used to improve and develop land management systems, including the effective and efficient use of nutrients and water to increase crop productivity. The study aimed to obtain information on nutrient uptake by maize and the efficiency of nitrogen fertilizers at some irrigation water levels in sub-optimal land. This study was conducted at the Research Station of Taman Bogo, East Lampung, Indonesia. The study used a split-plot design in a randomized group with three replications. The main plots consisted of water levels 100%, 80%, and 60% based on FAO’s recommendation, whereas the sub-plots were N fertilizer in the form of urea <sup>15</sup>N labels with the rates 0, 100, and 135 kg N ha<sup>-1</sup>. The results showed that the average grain yield of maize (8.0 t ha<sup>-1</sup>) was the highest for 135 kg N ha<sup>-1</sup> and 80% irrigation water. The application of 100 kg N ha<sup>-1</sup> with 80% irrigation water was sufficient for increasing N uptake in grain and biomass. The highest efficiency (15.7–16.7%) of N fertilizer on maize was shown by treatments of 135 kg N ha<sup>-1</sup>with 100% irrigation water and 100 kg N ha<sup>-1</sup> with 80% irrigation water. With the isotope method, the N efficiency from fertilizers can be traced</p>

Impact of integrated soil fertility management practices on maize yield in Ethiopia

Today, declining soil fertility is the main biophysical constraint to improve crop yield and poses a potential threat to food security. This study aims to explore the elements that could influence the adoption of integrated soil fertility management (ISFM) practices as well as their impact on maize yield. This study is based on a pseudo-panel collected by Ethiopia's central statistical agency (CSA) in collaboration with the World Bank. A Multinomial Endogenous Switching Regression model (MESR) was employed to achieve the specified objectives. The findings revealed that 15% of plots received no soil fertility-enhancing treatments, while 35% received a combination of inorganic fertilizer and manure to boost soil fertility. The average maize yield in the study was 3.44 tons per hectare, which was nearly equal to the average national yield in the prior year. Finally, maize yield was significantly influenced by soil fertility management measures, whether used alone or in combination of two or more soil fertility enhancing technologies. The extent of the impact, however, varies significantly depending on the inputs employed. Thus, using manure or compost alone had a moderate but significant impact on maize yield, but using inorganic fertilizer in combination with manure had the biggest impact. Therefore, policies that support the expansion of ISFM practices should be promoted. Farm households also receive technical assistance and training to better understand the use of ISFM practices, and policies that promote them should be expanded.

Diversity and Prediction of Corn Product Loss Due Weed Competition to Two Types of Dry Land Agroecosystem

The aim of the study was to determine which weed species had a significant effect on the reduction of maize yields, so that it could be determined which species should be controlled and which should not be controlled. The research was carried out using a descriptive method on dry land in Mumbul Sari Village, Bayan, North Lombok. Collecting data on population and growth of weeds and plants, using sample plots measuring 1 m2 placed at 10 points by random sampling. Parameters observed were weed species population, corn crop population plot-1, dry biomass weight of plot-1 weed, dry biomass weight of plot-1 corn, and dry seed weight of corn plot-1. Quantitative data analysis by calculating the value, relative density (RN), relative frequency (RF) and relative dominance (RD) to calculate the significant value index (SVI), and Summe Diminance Ratio (SDR). There were 2 species of puzzle weed, 10 species of Poaceae weed and 13 species of broadleaf weed. One species of puzzle weed, namely Cyperus rotondus and 3 species of Poaceae Digitaria longiflora, Paspalum conjugatum and Panicum repens, and 2 species of broadleaf weed, Amaranthus spp., and Synedrella nodiliflora, were very dominant and continued to exist during plant growth with respective SDR values each species 10.43%; 15.37%; 10.20%; 9.67 %; 10.00% and 5.80%. The competitiveness and relative weighted dominance of the 6 weed species were higher than other weed species, so that the six weed species were able to eliminate the average maize yield since the plants were 30 – 90 as much as 17.90%; 16.78%; 12.35%;10.88%; 9.18% and 3.40%

Modeling maize water consumption and growth under plastic film mulch using an agro–hydrological model: Searching for the optimal plant density in different hydrological years

Appropriate plant density is essential for crop production in rainfed areas. However, it is quite difficult to obtain the optimal plant density under plastic film mulch in different hydrological years through field experiments due to its limited treatments, and time and labor costs. Therefore, mathematical models are generally used for searching the optimal alternatives. In this paper, the Agro–Hydrological & chemical and Crop systems simulator (AHC) was adopted to model soil water dynamics, rainfed maize growth, and yield under plastic film mulch and various plant density conditions in Northeast China for different hydrological years. The results showed that the AHC model can simulate rainfed maize water use and growth under plastic film mulch and various plant density conditions, i.e., 60,000 (D1), 67,500 (D2), 75,000 (D3), 82,5000 (D4) and 90,000 plants ha−1 (D5). The average maize yields of all treatments in the severely dry (SD), moderately dry (MD), normal (N), moderately wet (MW), and severely wet (SW) years were 11440.3, 13685.4, 13821.5, 14704.8, and 14014.3 kg ha–1, respectively. Compared with non–mulch, plastic film mulch increased the maize basal crop coefficient by 0.08–0.11 and decreased the soil evaporation coefficient by 0.26–0.32, from SD and SW years, respectively. Thus, plastic film mulch augmented maize transpiration by 46.2–76.8 mm, while reduced evaporation by 163.5–186.8 mm across the simulated years. Ultimately, the maize yield under plastic film mulch was 5.9–17.4% higher than that without mulch. From D1 to D5 treatments, the decrease of soil evaporation coefficient was within 0.02 under plastic film mulch and was over 0.05 without mulch. Under plastic film mulch, the relations between plant density and net profit could be well described by the parabolic curves, and the recommended optimal plant densities of maize in the study area were 91, 101, 101, 105, and 101 thousand plants ha–1 in the SD, MS, N, MW, and SW years, respectively. Our findings provide management implications for maize cultivation in the rainfed areas of Northeast China.

Recent cover crop adoption is associated with small maize and soybean yield losses in the United States.

Cover crops are gaining traction in many agricultural regions, partly driven by increased public subsidies and by private markets for ecosystem services. These payments are motivated by environmental benefits, including improved soil health, reduced erosion, and increased soil organic carbon. However, previous work based on experimental plots or crop modeling indicates cover crops may reduce crop yields. It remains unclear, though, how recent cover crop adoption has affected productivity in commercial agricultural systems. Here we perform the first large-scale, field-level analysis of observed yield impacts from cover cropping as implemented across the US Corn Belt. We use validated satellite data products at sub-field scales to analyze maize and soybean yield outcomes for over 90,000 fields in 2019-2020. Because we lack data on cover crop species or timing, we seek to quantify the yield impacts of cover cropping as currently practiced in aggregate. Using causal forests analysis, we estimate an average maize yield loss of 5.5% on fields where cover crops were used for 3 or more years, compared with fields that did not adopt cover cropping. Maize yield losses were larger on fields with better soil ratings, cooler mid-season temperatures, and lower spring rainfall. For soybeans, average yield losses were 3.5%, with larger impacts on fields with warmer June temperatures, lower spring and late-season rainfall, and, to a lesser extent, better soils. Estimated impacts are consistent with multiple mechanisms indicated by experimental and simulation-based studies, including the effects of cover crops on nitrogen dynamics, water consumption, and soil oxygen depletion. Our results suggest a need to improve cover crop management to reduce yield penalties, and a potential need to target subsidies based on likely yield impacts. Ultimately, avoiding substantial yield penalties is important for realizing widespread adoption and associated benefits for water quality, erosion, soil carbon, and greenhouse gas emissions.

Disintegrating the impact of climate change on maize yield from human management practices in China

Climate warming has posed one of the greatest threats to global food security during the 21st century. Evidence suggests that such a threat could be partly offset by promoting food production through human management. Most studies have focused on quantifying the impact of climatic factors on food quantity. However, the contributions of human management practices, including fertilization and irrigation, to food production are yet to be comprehensively understood. Using integrated information on climate, fertilizer use, and irrigation water allocation across China's 208 prefecture-level administrative divisions, as well as four spatial panel models, we have successfully disintegrated the relative effects of climate change and human management practices on China's maize yield. From 1982 to 2013, the average maize yield in maize planting regions in China increased by 1.7 times. The overall impact of human management (fertilizer use and irrigation) on maize yield was higher than that of climate change (based on the optimal spatial Durbin model where the coefficients of most factors were significant at p < 0.01; R2 = 0.65). The vapor pressure deficit (VPD) was the main influencing factor on maize yield followed by nitrogen and phosphorus (N&P) fertilizer use, precipitation, and diurnal temperature range (DTR) respectively. For example, maize yield would decrease by 15.0% per 0.1 kPa increase in VPD and increase by 29% per 10 g added in N&P fertilizer per square meter. Specifically, the VPD negatively influenced the maize yield in the Northern spring and the Southwest maize region, while the increased temperature negatively influenced the maize yield in the Huang-Huai spring-summer maize region. The N&P fertilizer use, precipitation, and diurnal temperature range all positively influenced the maize yield. N&P fertilizer use in the South maize region had a greater effect on improving maize yield than the other regions. The yield in the South maize region benefited more from human activities. This research could provide a timely reference for improving food production in China's maize planting regions and maintaining food security.

Optimizing crop rotation increases soil carbon and reduces GHG emissions without sacrificing yields

Enhancing soil organic carbon (SOC) while concurrently reducing greenhouse gas (GHG) emissions and without compromising yield is a contemporary challenge for many agricultural sectors across the globe. In China, resolving the "carbon- food" nexus is a key pillar of government policies aimed at constraining “Carbon Peak” and delivering “Carbon Neutrality”. The present study explores the potential to increase SOC stocks while reducing GHGs emissions, without sacrificing crop yields considering crop rotation optimization under different irrigation managements in the North China Plain (NCP) based on a 6-year experiment. We found higher crop yields for the irrigated treatments compared with the rainfed treatments, demonstrating that rainfed crops were constrained by water deficit stress in the region. Yield was highest in the winter wheat-summer maize rotation (WM), followed by yields of the winter wheat-summer soybean (WS), while the average yields of winter wheat-summer maize-spring maize (WMMs) were lowest. SOC stocks in the surface soil (0–20 cm) increased for the irrigated treatments, but soil carbon sequestration (i.e. the rate of SOC stocks change over time) for the rainfed treatments decreased for all treatments. SOC stocks for WMMs was greatest of all treatments, leading to the highest carbon sustainability index (CSI) for this treatment. Nitrous oxide (N2O) emissions were 23–57% higher in the irrigated treatments than the rainfed treatments for the three rotations, which was highest in WMMs and lowest in WS. Carbon footprints (CFs) were highest in WS and lowest in WMMs. Overall, we found that increasing SOC stocks reduced CFs and increased yield. WMMs with irrigation was the most effective treatment for promoting SOC sequestration and mitigating GHG emissions with relatively high yield in this study, suggesting that crop rotations that are (1) more intensive and (2) grow more aboveground biomass are more likely to promulgate lower CFs and contribute towards national emissions abatement targets, such as those aimed at Net Zero.

Intercropping-driven nitrogen trade-off enhances maize productivity in a long-term experiment

Intercropping improves land productivity by exploiting species complementarities to achieve sustainable agriculture. Intercropping systems, therefore, require a nitrogen (N) management approach that matches temporal and spatial N supply with crop requirements. Present field-based study (started in 2013) explored the effects of intercropping of maize ( Zea mays L. ) with legumes [peanut ( Arachis hypogaea ) and soybean ( Glycine max )] and non-legumes [gingelly ( Sesamum indicum L. ) and sweet potato ( Dioscorea esculenta )] on maize productivity and N trade-off. Compared with maize monoculture, intercropping with gingelly, peanut, soybean, and sweet potato all significantly improved maize average yield (2013 and 2021), average N use efficiency (NUE), average N partial factor productivity (PFPN), and plant N uptake by 8–29%, 28–49%, 20–80%, and 16–35%, respectively. The N losses via ammonia volatilization and runoff in intercropping systems decreased by 12–19% and 11–43% respectively, compared with monoculture. Soil total N, inorganic N (NH 4 + -N and NO 3 - -N), and microbial biomass N (MBN) contents as well as the urease, β-1,4-N-acetyl-glucosaminidase (NAG), and leucine aminopeptidase (LAP) activities varied among different intercropping systems and maize growth periods. Maize productivity (yield, PFPN, and NUE) was positively correlated with plant N uptake (R 2 = 0.66–0.92, P < 0.001) and soil MBN content (R 2 = 0.41–0.47, P < 0.01), while it was found negatively associated with N losses (R 2 = 0.35–0.56, P < 0.05), soil N availability (R 2 = 0.27–0.67, P < 0.05), and NAG activity (R 2 = 0.36–0.55, P < 0.05). These findings collectively indicated that regulating the balance between soil N supply and plant N uptake in an intercropping system with low N fertilization could achieve high productivity. This study highlighted the importance of understanding the complex interaction between crop development and intercropping practices in improving maize productivity and N trade-off. • Intercropping increased average (2013 and 2021) maize yield by 8–29%. • Intercropping improved average NUE by 28–49% and maize N uptake by 16–35%. • N loss via ammonia volatilization and runoff decreased by 11–43% duo to intercropping. • Maize productivity was primarily related to plant N uptake, soil N dynamics and N loss. • Intercropping-driven plant-soil N trade-offs contributed to increased maize productivity.

Performance Evaluation and Identification of New Quality Protein Maize Inbred Lines

Background: Maize plays a critical role in meeting high food demand. It is a globally widely adopted and cultivated crop. Hybrid and open-pollinated varieties development from fixed inbred lines is one of the strategies for the improvement of maize production. Compared with the world average, the national average maize yield is low in Ethiopia. According to this development and selection of promising germplasm has indispensable value for developing high-yielding maize varieties. The study consists of 21Quality Protein Maize (QPM) lines, two QPM testers lines, and one Conventional Maize (CM) line check (FS67). They were evaluated in RCBD with two replications at Ambo and Arsi-Negele. The objective was to identify new lines with good performance compared with released QPM checks and CM lines.&#x0D; Results: There is a significant difference between the lines for 28 traits in Ambo and 24 traits at Arsi-Negele. In combined mean performance analysis, the highest yielding line (L8) exceeded the mean of all line checks, mean QPM checks, CM line check (FS67), and best QPM line check (CML144) by 34.89%, 54.80%, 7.30%, and 25.31%, respectively for GY. The value of EPP ranged from 0.91 (L14) to 1.85 (L3) with an overall mean of 1.19). The highest yielding line (L8) had the 2nd highest EPP (1.63). Mean EPP of the top five QPM lines was less by 5.45%, 4.96%, 22.41%, and 6.41% compared with the mean of all checks, mean of QPM line checks, best QPM check, and CM line check, respectively. The high yielder line (L8) had a higher mean value than the mean of lines checks (CML144, CML159, and FS67), mean of QPM lines checks, best QPM check (CML144), and FS67 by 25.71%, 26.36%, 3.16%, and 24.43%, respectively.&#x0D; Conclusion: In general, the study confirmed the existence of promising new QPM parental lines. These promising lines can be used as source material in the breeding program for further improvement.

Standard Heterosis Estimation for Quality Protein Maize Hybrids Over Best Released and Commercialized Hybrids

Maize plays an indispensable role in meeting high food demand. It is globally one of the most widely adopted and cultivated crops. Hybrid development from fixed inbred lines is one of the tactics to boost maize production. The national average maize yield in Ethiopia is low and thus, selection of promising germplasm, knowledge of combining ability, and heterotic grouping are prerequisites to develop high-yielding maize varieties. Forty-two Quality Protein Maize (QPM) single crosses (21 inbred lines each crossed with two testers) along with three popular standard hybrid checks were evaluated in two replications using alpha lattice design during the 2017 cropping season at Ambo, Arsi-Negele, and Kulumsa. The objective of this study was to estimate standard heterosis for grain yield (GY), and other agronomic and morphological characters. Significant difference among crosses was observed for 19 traits at Ambo, 14 traits at Arsi-Negele, and 19 traits at Kulumsa in the hybrid trial. For GY, at Ambo, almost all crosses showed negative heterosis against the best check (AMH853). At Arsi-Negele 14 crosses had positive standard heterosis, from these only three crosses: L8xT1 (50.8%), L8xT2 (46.6%), and L7xT1 (33.9%) showed significant difference against Jibat but at Kulumsa, the difference for standard heterosis was positive but non-significant only by two crosses: (L7xT1 (6.6%) and L19xT1 (4.7%). Based on mean grain yield and standard heterosis, L8xT2, L7xT1, L8xT1, L19xT1, L6xT2, and L18xT1 are promising. The study of the results highlighted that the breeding program was successful in generating superior QPM hybrids. Based on the finding we suggest that it is better to use the parents of theses hybrids as potential source materials in the breeding program through to form different crosses formation.

Estimation of General and Specific Combining Ability Effects for Quality Protein Maize Inbred Lines

Background: Maize (Zea mays L.) plays a critical role in meeting high food demand. It is globally one of the most widely adapted and cultivated crops. Hybrid development from fixed inbred lines is one of the strategies for the improvement of maize production. The national average maize yield in Ethiopia is low and thus, selection of promising germplasm and knowledge of combining ability are prerequisites to developing high yielding maize varieties. Forty-two Quality Protein Maize (QPM) crosses (21 inbred lines each crossed with two testers) along with three popular standard hybrids were evaluated in two replications using alpha lattice during the 2017 cropping season at Ambo, Arsi-Negele, and Kulumsa. The objectives of this study were to identify lines with high GCA and estimate the SCA of crosses for grain yield, and other agronomic and morphological characters.&#x0D; Results: Significant difference among crosses was observed for 19 traits at Ambo, 14 traits at Arsi-Negele, and 19 traits at Kulumsa in the hybrid trial. Regarding the GCA effect, L8 had a significant difference to the positive side with the highest magnitude of GCA effect at three locations (3.40, 2.03, and 1.88 GCA effect values at Arsi-Negele, Ambo, and Kulumsa, respectively) which is followed by L7 for GY. All crosses did not show a significant SCA effect for GY in both directions at Ambo and Arsi-Negele but at Kulumsa, five crosses: L2xT1(1.89), L13xT2(1.88), L7xT1(1.86), L4xT2(1.49) and L19xT1(1.41) showed significant difference. In the combined analysis for six traits, Additive gene action was more important which was manifested by a higher sum square contribution of DS (79.6) EPP (79.3%), EL (80.0%), KPR (80.1%), ED (78.5%) and TSW (79.1%).&#x0D; Conclusion: Based on mean grain yield, and combining ability, L8xT2, L7xT1, L8xT1, L19xT1, L6xT2, and L18xT1 are promising crosses that could be forwarded for further use in maize breeding programs for further works.

Performance Evaluation and Identification of Highland Quality Protein Maize Hybrids in Ethiopia

Background: Maize plays an indispensable role in meeting high food demand. It is globally one of the most widely adopted and cultivated crops. Hybrid development from fixed inbred lines is one of the strategies for the improvement of maize production. The national average maize yield is low in East Africa; thus, the selection of promising germplasm has a great role to meet the high food demand of growing the population. Forty-two Quality Protein Maize (QPM) crosses (21 inbred lines each crossed with two testers) along with three popular standard hybrids checks were evaluated in two replications using alpha lattice during the 2017 cropping season at Ambo, Arsi-Negele, and Kulumsa. The objective of this study was to evaluate and select the best new QPM hybrids for grain yield, and other agronomic and morphological characteristics.&#x0D; Results: Significant difference among crosses was observed for 19 traits at Ambo, 14 traits at Arsi-Negele, and 19 traits at Kulumsa. Out of 28 traits studied, six of them did not show genotype by location interaction but they showed a significant genotypic effect. These traits were: Days to Silking (DS), Number of Ears per plant (EPP), Ear Length (EL), Kernels Per Row (KPR), Ear Diameter (ED), and Thousand Seed Weight (TSW). Based on the mean performance in the combined analysis, from 42 new QPM crosse, six of them (L8xT2, L7xT1, L8xT1, L19xT1, L6xT2, and L18xT1) were scored higher grain yield compared with the mean of the three standard checks and best conventional maize (CM) check (AMH853). L8xT2, L7xT1, L8xT1 crosses showed a higher grain yield advantage over the best check (AMH853) by 20.87, 14.13, and 13.63%, respectively.&#x0D; Conclusion: The study implicated the existence of a difference between the newly developed hybrids and the standard check varieties. In general, the study enabled us to identify promising crosses that could be forwarded for further use in maize breeding programs in future work.

Mid-parent and Better Parent Heterosis Study on Highland Quality Protein Maize Hybrids in Ethiopia

Determination of heterosis in maize hybrids is necessary for the identification of superior F1 hybrids for breeding programs. Therefore, this study was conducted to estimate the amount of mid parent (MPH) and better parent heterosis (BPH) for grain yield, yield-related, agronomic, and morphological traits. Hybrid development from fixed inbred lines is one of the strategies for the improvement of maize production. The national average maize yield in Ethiopia is low and thus, selection of promising germplasm, knowledge of combining ability, and heterotic grouping are prerequisites to developing high-yielding maize varieties. Forty-two Quality Protein Maize (QPM) crosses (21 inbred lines each crossed with two testers) along with three popular standard hybrids were evaluated in two replications using alpha lattice during the 2017 cropping season at Ambo and, Arsi-Negele. Parental line trials consisting of 21 lines, two testers, and one conventional maize (CM) parent check (FS67) were established in two replications laid out using RCBD side by side with the hybrid trials at Ambo and Arsi-Negele. At Ambo, almost all crosses showed positive and significant BPH except three crosses (L1xT1, L4xT1, and L13xT1). The maximum BPH (276.2%) was obtained from L17xT2. Similarly, at Arsi-Negele, most of the crosses had positive and significant BPH except for five crosses for BPH which are showing negative heterosis. The highest BPH was obtained from L10xT2 at Arsi-Negele. Generally, the high yielding crosses had reasonable BPH. Based on the result promising crosses and lines were identified. Some of the crosses showed good performance in terms of heterosis against the mid parent and better parent: L17xT2 (329.88% MPH, 276.18% BPH), L3xT2(320.05% MPH, 273.91%BPH), and L19xT2(2802.57% MPH, 247.31% BPH) at Ambo, whereas at Arsi-Negele L10xT2 (128.38% MPH, 111.27%BPH) and L11xT2(115.33% MPH, 98.00% BPH) showed the higher heterosis compared with the mid parent and better parent. Crosses that showed best yield performance were: L8xT2, L7xT1, L8xT1, L19xT1, L6xT2, and L18xT1. These crosses should be reconsidered for further evaluation and possible release.

The Accumulation of Biomass Pre- and Post-Silking Associated with Gains in Yield for Both Seasons under Maize–Rice Double Cropping System

Due to relatively low yield as well as low resources use efficiency with double rice (Oryza sativa L.) cropping systems (RR), exploring new cropping systems to increase yield and resources use efficiency simultaneously has become a large challenge of the middle reaches of the Yangtze River (MRYR). Our previous study demonstrated that the maize (Zea mays L.)–rice cropping system (MR) exhibited higher superiority of yield and resource use efficiency compared with the conventional double-rice cropping system. However, the reason for the yield increases in both maize and rice and the physiological processes involved in those two crops under MR are poorly understood. A 3-year field experiment was conducted at two sites (Wuxue and Jingmen) from 2016 to 2018 to examine the differences in dry matter (DM) accumulation, soil properties, and resources use efficiency between the MR and RR cropping systems. Compared with RR, the annual yield of MR was 18.2–26.3% and 15.4–31.5% higher across three years at Wuxue and Jingmen, respectively. The average yield of maize in MR was 36.5% and 21.9% higher than that of early rice in RR at Wuxue and Jingmen, respectively. The yield increase for maize was mainly attributed to the 29.7% (Wuxue) and 28.5% (Jingmen) increases in post-silking DM accumulation due to the higher plant growth rate promoted by the higher net assimilation rate and radiation use efficiency. For the late rice in MR, the average yield was 10.9% and 14.5% higher than that of late rice in RR at Wuxue and Jingmen, respectively, which was promoted by the 7.8–23.3% increase in pre-anthesis DM accumulation due to improved soil properties. Compared with RR, the MR cropping system exhibited increased soil pH, total organic carbon, and mineral nitrogen, and decreased the bulk density in the late rice season. As a result of greater yield in both seasons under MR, the annual accumulated temperature and radiation use efficiency, partial factor productivity from applied nitrogen, and water use efficiency of MR were 17.7–26.4%, 22.2–25.5%, 5.5–7.8%, and 33.6–48.7% higher than those of RR, respectively. We conclude that the higher yield in the MR than in the RR cropping system was mainly attributed to the accumulation of post-silking biomass due to maximized use of radiation in the maize season, and the accumulation of pre-anthesis biomass due to improved soil nutrients in the late rice season.

Optimizing sulfur fertilizer application rate for profitable maize production in the savanna agroecological zones of Northern Ghana

Although several studies have established the importance of sulfur (S) in increasing maize productivity in the savanna agroecological zones (AEZs) of northern Ghana, the economically optimum S application rate is still unknown. In a two-year study at eight locations across the AEZs, we determined the economically optimum S application rate for S-deficient soils. We compared eight S application rates, ranging from 0 to 70 kg ha−1 at 10 kg intervals, for optimal maize productivity and profitability. The study identified 30 kg S ha−1 as the minimum rate that resulted in a plant tissue S concentration above the critical level of 0.15%. Although increasing the S application rate resulted in increases in maize grain yield, application of S beyond a rate of 30 kg ha−1 resulted in increases in maize grain yield that were not statistically significant and leveled off at 50 kg S ha−1. Application rates ≥50 kg ha−1 resulted in a high proportion of the applied S not taken up by the plant and, thus, subject to losses from the soil. Based on agro-input prices at the local level and the farm-gate prices of maize, the greatest potential profit resulting from S application was observed at 30 kg S ha−1, with a projected average maize yield of between ∼4.2 and 5.3 Mg ha−1, representing >90% of the observed yield with the highest S application rate of 70 kg ha−1. Thus, we conclude that, for sustainable and profitable maize production in S-deficient soils of the savanna AEZs of northern Ghana, an S applications rate of 30 kg ha−1 is economically justified.

Effect of Irrigation Regime On Yield and Water Productivity of Maize (Zea Mays) in the Lake Tana Basin, North West Ethiopia

Proper scheduling gave water to the crop at the right time in the right quantity to optimize production and minimize adverse environmental impact. Therefore, the objective of this study is to quantify the effects of irrigation regimes on yield and yield components of Maize in the Lake Tana basin during 2016-2018. CROPWAT 8.0 model was used to determine the crop water requirement. Almost all parameters were adopted the default value of CROPWAT 8.0. Field data including; field capacity (FC), permanent wilting point (PWP), initial soil moisture depletion (%), available water holding capacity (mm/meter), infiltration rates (mm/day), and local climate data were determined in the study area. The treatments were arranged in factorial combinations with five irrigation depths (50, 75, 100, 125 and 150% of ETc) and two irrigation intervals (14 and 21 days) laid out in a randomized complete block design with three replications. The result was analyzed using SAS 9 software and significant treatment means separated using least significant difference at 5%. The result showed that the interaction of irrigation depth and irrigation frequency has no significant effect on the average grain yield and water use efficiency of maize. At koga, the highest grain yield (7.3 t ha-1) and water use efficiency (0.9 kg m-3) obtained from 100% ETc. while, at Ribb the highest grain yield (10.97 t ha-1) and water use efficiency (1.9 kg m-3) obtained from 21 days irrigation interval. Therefore, for Koga and similar agro ecologies maize can irrigated with 562 mm net irrigation depth and 21-day irrigation interval and at Rib and similar agro ecologies maize can irrigated with 446.8 mm net irrigation depth and 21- days irrigation interval.

Optimum fertilizer application rate to ensure yield and decrease greenhouse gas emissions in rain-fed agriculture system of the Loess Plateau

Application of nitrogen (N) can increase the supply of N in soil and, in turn, can lead to higher yield—but also to large increase in emissions of greenhouse gases (GHGs) if applied in excess. To determine the optimum dose of N for maize planting system, we analysed the relationship between yield and emissions of GHGs at seven levels of N, namely 50, 100, 150, 200, 250, 300, and 350 kg ha−1, using the DNDC (denitrification decomposition) model and maize grown with and without mulching. The model simulated the following variables: maize production; emissions of carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4); global warming potential (GWP); and GHG intensity (GHGI). We used data from 1980 to 2013 for a rain-fed region of the Loess Plateau in north-western China and validated the DNDC model against data from field experiments. The model performed well in simulating yield and GHG emissions (Adj.R2 > 0.61). Under mulching, the average yield of maize was 3.6–12.2 t ha−1 and the partial factor productivity was 73.1–35.0 kg kg−1; and both of these were significantly higher 78%–236% than those in the crop without mulching. The emissions of CO2, N2O, and the GWP increased with the increase in the dose of N whereas CH4 emissions remained unaffected by the dose. Mulching increased yields significantly in the north-western region, and the GWP and GHGI were higher mainly in the central and north-western regions. The optimum dose of N for maize grown with mulching ranged between 150 kg ha−1 and 200 kg ha−1 and offers the best balance between higher yield and lower emissions. The optimum dose may promote the development of mulched maize and provide a reference standard for dryland agriculture in zones with similar climates elsewhere in the world.

Yield and quality properties of silage maize and their influencing factors in China.

Silage maize (Zea mays L.) is one of the most important forages in the world, and its yield and quality properties are critical parameters for livestock production and assessment of forage values. However, relationships between its yield and quality properties and the controlling factors are not well documented. In this study, we collected 5,663 observations from 196 publications across the country to identify the relationships between yield and quality properties of silage maize and to assess the impact of management practices and climatic factors on its yield and quality in China. The average dry matter yield of silage maize was (19.98±6.93) Mg ha-1, and the average value of crude protein, ether extract, crude ash, crude fiber, acid detergent fiber, neutral detergent fiber, nitrogen-free extract, and relative feed value was 7.86%±1.71%, 2.53%±1.01%, 5.05%±1.66%, 23.97%±6.34%, 27.62%±7.12%, 51.60%±9.85%, 59.68%±7.72%, and 131.17±31.49, respectively. In general, its nutritive value decreased as its yield increased. Increasing planting density could increase the yield but inhibit the nutritive values, while increasing fertilization could benefit the nutritive values. Geographically, the yield increased and the nutritive value decreased from warm (south) to cold (north) regions. The length of growth duration was a major controlling factor for the patterns of these properties. Our findings provide insights for police-makers to make strategy for achieving high yield and good quality of silage maize and help local people to implement better management practices.

Stereoscopic Planting in Ridge and Furrow Increases Grain Yield of Maize (Zea mays L.) by Reducing the Plant’s Competition for Water and Light Resources

Increasing planting density is an important ways to increase maize yield. A hot topic of conversation in the current research is how to improve crop light efficiency and yield potential by optimizing the cultivation mode under high density planting is a hot topic in current research. Thus, in this study, a field experiment was conducted to explore the effects of stereo-planting patterns on water and the utilization light resource and maize yields. Planting patterns included the conventional flat planting pattern (as the control, CK) and the stereo-planting in ridge and furrow (T). Each planting pattern had three planting densities, i.e., 60,000 plants ha−1 (D1), 75,000 plants ha−1 (D2) and 90,000 plants ha−1 (D3). The results showed that stereo-planting affected the physiological characteristics of plants by changing the spatial distribution of soil moisture. At the silking stage (R1), photosynthetic rate (Pn) of plants on the ridge was similar to CK, and transpiration rate (Tr) was significantly lower than that of CK. Pn of maize in the furrow was significantly higher than that of CK, and Tr was similar to CK. Stereoscopic planting had different effects on intraspecific competition intensity in maize population in different growing stages. In the six-leaf stage (V6), stereo-planting increased competition intensity of maize on the ridge, but lowered that of maize in the furrow by affecting the spatial distribution of soil moisture. During the R1 stage, stereo-planting increased the light transmittance rate within the canopy and eased the plant’s competition for light by reducing plant height and leaf area of maize under three density conditions. Stereo-planting had no effect on grain yield and dry matter accumulation of ridge-planted maize in the later growing stage, but it did increased the dry matter accumulation and grain yield of furrow-planted maize due to the improvement of the light environment and photosynthetic characteristics of the population. In two test years, stereo-planting increased 5.0–11.0% average yield of maize compared to CK under three density conditions. These results indicate that stereo-planting can reduce the plant’s competition for light and water resources and improve its physiological traits of plant by optimizing its spatial distribution of soil moisture and canopy structure, thus further increasing grain yield of maize under high-density planting conditions.

Assessment of Three IAARD Maize Productivity In Tobadak District, Central Mamuju, Indonesia

Assessment of three IAARD maize productivity was conducted in Tobadak sub-district, Central Mamuju. The purpose of the assessment was to determine the productivity of three IAARD hybrid maize. The area of study 3 ha, applying Integrated Crop Management (ICM) models. Varieties which assessment Nasa 29, JH 37 and JH 45, and NK 212 as comparison variety. The experiments were arranged in a randomized block design which 3 times replication. Observations were made on the growth and maize yield. Based on the results of mapping of Indonesian Center for Agricultural Land Resources Research and Development (ICALRRD), land suitability classes for maize in Central Mamuju Regency which are quite suitable (S2) and marginal (S3) are 4,308 ha and 87,889 ha respectively, while that not suitability (N) covering an area of 193,441 ha with limiting factors including nutrient retention, nutrient availability, water availability, and root media. The studied was show that IARRD hybrid maize can increase productivity. The results showed that Nasa 29, JH 37, and JH 45 respectively gave yields 12.87 Mg, 9.02 Mg, and 7.77 Mg ha-1, higher than the average maize yield achieved in West Sulawesi and Central Mamuju Regency, each 4.70 Mg ha-1and 5.19 Mg ha-1. Nasa 29 gave higher yields and was significantly different compared to NK 212 (9.65 Mg ha-1) as comparison variety, and JH 37 variety was not significantly different with NK 212, but while JH 45 variety had lower results and was significantly different with NK 212. Nasa 29 and JH 37 varieties have the opportunity to be developed in Tobadak district, Central Mamuju, West Sulawesi.