Average Ear Weight Research Articles

Characteristics of Maize Roots under Subsurface Drip Irrigation through Various Oxygen Treatment

In Korea, irrigation technology using subsurface drip irrigation (SDI) is new in agriculture system. Many limitations of SDI are not well known. SDI can damage crops from overwatering. To address this weakness, it is important to improve and test the applicability of the SDI with air injection (oxygation). Therefore we investigated soil oxygen (O2) and carbon dioxide (CO2), root characteristics and yield of maize using two conditions of soil moisture regime: field capacity (FC) × 100% and 120%. Maize was planted, and then air was injected by compressor and venturi. In the field, irrigation was controlled by a controller connected to soil moisture sensors. Soil moisture sensors were measured at 20 cm below soil surface. Soil O2 and CO2 were measured at 10 and 30 cm below soil surface before and after oxygation. Root activity was measured from tip of roots. Root volume and dry weight were measured. Post-harvest, number and weight of maize ears were surveyed as well. As a result, soil oxygen values increased by 59% in the compressor treatment and by 34% in the venture treatment. However, soil CO2values did not depend on the oxygation. In all soil moisture treatments, the activity of oxygated roots was greater than that of the control, and root activity was increased by 152%. Root volume and dry weight were also greater than those in the control. No significant effect of soil moisture was found on the number and weight of ears of maize. The average ear weight of maize in the FC 100% soil moisture treatment was 1,292 kg 10a-1 in the oxygation and 1,278 kg 10a-1 in the control. In addition, no effect of oxygation was observed on number and weight of ears. The average ear weight of maize in the FC 120% soil moisture treatment was 1,229 kg 10a-1 in the oxygation and 960 kg 10a-1 in the control. Maize yield was 28% greater in the oxygation treatment than that in the control. The yield of maize grown in the control field showed a tendency to decrease as the soil moisture content increased. At FC 120% soil moisture, the ear weight of control maize was reduced by 25% compared to FC 100% soil moisture. These results reflected that the oxygation process had a great effect on the root growth even in humid conditions, which was expected to have a positive effect on the maize plants planted above-ground.Root activity, dry weight and volume of corn as a result of soil moisture and oxygation; Soil moisture treatments (field capacity × 100%, field capacity × 120%), Oxygation treatments (compressor, venturi), Control (no air was injected). Soil moisture regime Oxygation treatment Root activity (µg g-1 h-1) Root dry weight (g) Root volume (cm3) 100% of field capacity Compressor 50.1 ± 1.69 b† 49.5 ± 19.25 a 269 ± 83.8 a Venturi 67.8 ± 3.25 a 44.6 ± 10.17 a 224 ± 34.9 a Control 32.2 ± 2.08 c 12.5 ± 5.55 b 59 ± 43.8 b 120% of field capacity Compressor 50.8 ± 1.07 a 42.4 ± 0.74 ab 225 ± 5.0 b Venturi 39.2 ± 1.54 b 73.7 ± 25.75 a 326 ± 56.6 a Control 35.8 ± 1.52 c 14.6 ± 9.81 b 60 ± 48.2 c †a, b and c represent significant difference level at 95%.

Long-Term Effects of Fertilizers with Regional Climate Variability on Yield Trends of Sweet Corn

Climate change affects global crop production year after year. Exploring the impact of different fertilization methods on crop yield stability has become an extremely important topic in sustainable agriculture. The objective of this study is to explore the effects of various fertilization regimes with climate variability on yield stability for sweet corn production in southern Taiwan. Three fertilization treatments composed of chemical fertilizer only (CF), integrated fertilizer (half organic/half chemical fertilizer) (IF), and organic fertilizer only (OF) were implemented from 2009 to 2018 based on the well-maintained soils since 1988. While the same amounts of these fertilizers were applied during the period, we found that different fertilization changed the marketable yields of fresh fruit (ear), which slightly increased for organic fertilizer, but substantially decreased for both chemical (p = 0.0001) and integrated (p = 0.0061) fertilizer. Thus, based on these 10 years of observation, yields among fertilization treatments were analyzed with weather and soil parameters to determine the possible factors involved. Both multiple linear regression equation (p < 0.0001, adj. R2 > 0.57) and regression tree analysis illustrated significantly negative correlations between average ear weight and relative humidity under the chemical fertilizer treatment. In this study, we show for the first time that chemical fertilizer had the lowest yield resilience in response to regional relative humidity change compared to organic and integrated fertilizers. Our results also indicate that specific soil microbes have the potential to help sweet corn face environmental vulnerability in subtropical regions.

Diallel analysis of resistance to Fusarium ear rot in Brazilian popcorn genotypes

Among the ear rot pathogens, species of Fusarium cause significant economic losses to popcorn production. To generate popcorn genotypes resistant to Fusarium ear rot, the combining ability of popcorn lines in diallel crosses were assessed during two cropping years: the first from Mar to Sep 2015 and the second from Sep 2015 to Jan 2016. The traits analyzed were: average ear weight (AEW, kg ha−1); grain yield (GY, kg ha−1); popping expansion (PE, g mL−1), Fusarium incidence on ears (EIFU, %); Fusarium ear rot severity index (FSI, %), percentage of fungal-infected kernels (KIF), and percentage of Fusarium-infected kernels (KIFU). Non-additive genetic effects prevailed in the expression of resistance to Fusarium ear rot and grain yield, while additive effects were the most prominent in the expression of popping expansion. Among 56 hybrids, seven showed outstanding grain yield, desirable popping expansion, and resistance to Fusarium ear rot. The less susceptible hybrids to ear rot produced high grain yield and popping expansion. Two disease-related traits, KIFu and EIFu, allowed to best differentiate among the genotypes.

Influence of Degradation of Chitosan by Gamma Radiation on Growth Enhancement of Corn

The present study reports the effect of different molecular weight and concentration of irradiated chitosan on preliminary plant growth promoter test of corn in potting experiment. The average molecular weights of degraded chitosan were determined by intrinsic viscometric and GPC analysis. Four kinds of ultrafiltration membrane were used to separate the 100 kGy irradiated chitosan into five fractions (<10, 10-30, 30-50, 100-300, and >300 kDa). All five separated fractions, the irradiated and unirradiated chitosan were used for plant growth test of corn. The effects of different molecular weight fractions and concentrations of chitosan on average plant height, leaf greenness, average ear number and average ear weight of corn were studied. The results show that irradiated and unirradiated chitosan at concentrations ranging from 20, 50 and 100ppm are effective for the growth promotion of corn plant, such as plant height, number of ear and ear size, in comparison with the control (untreated chitosan).

Efeito da aplicação de esgoto doméstico primário na produção de milho no assentamento Milagres (Apodi-RN)

The application of treated domestic wastewater is an effective way to control environmental pollution, and is a viable option for increasing water availability in arid and semiarid regions. This study analyzed the production of maize (Zea mays L) fertilized with primary sewage at the rural settlement of Milagres in Apodi-RN. The study evaluated the following characteristics of maize: plant height, stem diameter, number of leaves, average ear weight with and without straw, wet and dry grain weight. The study found that fertigation with primary sewage resulted in higher values of plant height (PH), stem diameter, number of leaves, husked ear weight, ear weight without straw, wet weight of grains, dry weight of grains and grain yield compared to the same characteristics when artesian well water was used. Domestic sewage provides a source of nutrients for agricultural production.

Avaliação de híbridos de milho sob três densidades populacionais em fronteira agrícola no Maranhão

The aim of this study was to evaluate the agronomic performance of corn hybrids in three densities. The experimental design was randomized block in factorial 2x3 with four replications. No interaction between cultivars and density for any of the characters. Significant differences among hybrids, except for the number of rows of grain. The hybrid 2B707 showed greater height, ear length, number of kernels per row, ear weight and grain yield. The 2B710 hybrid overcomes 2B707 in ear diameter and grain weight. It was found that increasing the density a significant decrease in spike length, number of kernels per row and average ear weight. Also there was a decrease, but not significantly, with increasing density, the number of rows and weight of 100 grains. The ideal population was 55,000 plants where the yield was higher.

Produção do milho doce cv: superdoce em sucessão ao plantio de diferentes cultivares de inhame e adição de cama-de-frango

O experimento foi conduzido no período de 20/09 a 17/12/99 no Núcleo Experimental de Ciências Agrárias da UFMS, em Dourados, em solo classificado como Latossolo Vermelho distroférrico, textura argilosa. Avaliou-se a produtividade do milho híbrido Superdoce, sob população de 35.000 plantas ha-1, em sucessão aos clones de inhame Chinês, Japonês, Macaquinho, Cem/Um e Branco, cultivados com a adição ao solo de 14 t ha-1 de cama-de-frango de corte semi-decomposta (CFCSD) colocada no sulco de plantio, em cobertura ou incorporada. As alturas médias das plantas (228,1 cm) e de inserção das primeiras espigas (79,1 cm) e o diâmetro dos colmos (média de 2,5 cm ) das plantas de milho não foram influenciados significativamente pelos tratamentos da cultura anterior. O número (44.553 espigas ha-1) e o índice de espigas (1,254) foram maiores no solo cultivado com inhame e com a incorporação de CFCSD, e onde cultivou-se o clone de inhame Branco (43.902 espigas ha-1), sem efeito de interação. Os pesos totais das espigas com palha (11,9 t ha-1) onde foi cultivado inhame com a incorporação de CFCSD foram 7,6 e 11,7% maiores, mas com peso médio de espiga de 0,3 kg e que foi 4,0 e 4,3% menor em relação à área onde utilizou-se o resíduo vegetal em cobertura e no sulco, respectivamente. Os pesos totais das espigas sem palha (9,6 t ha-1) tiveram o mesmo comportamento que aquelas com palha, mas as diferenças foram de 17,9 e 21,1% e com peso médio das espigas de 0,2 kg que foi 5,4 e 3,9% maiores, na mesma ordem. A maior produção total de grãos de milho foi de 5,5 t ha-1 obtida na área onde para o inhame foi incorporada a CFCSD, sendo 12,6% e 17,2% maior em relação a adição no sulco e como cobertura, respectivamente.

UTILIZING POULTRY LITTER AS A FERTILIZER: SWEET CORN YIELD MINERAL NUTRITION, AND SOIL CHEMISTRY

Composted poultry litter (PL) containing 2.98% N was hand-applied to plots in a split-plot design with 3 replications. Application frequency (total, split) was the major plot and rate (0, 10.9, 21.7, and 43.6 Mg·ha-1) was the sub-plot. Rate was based on total N content of the PL and N requirement for maximum sweet com production. Comparisons were made with a fertilizer blend (FB) containing 23.8N-4.3P-4.1K at a total rate of 564 kg·ha-1 in split applications. Leaf area and average ear weight of sweet com ('Merit') were not affected by frequency or rate. Increasing PL rate from 10.9 Mg·ha-1 to 21.2 Mg·ha-1 increased yield by 3128 kg·ha-1. An increase to 43.6 Mg·ha-1 decreased yield which was probably due to an observed reduction in plant stand. When comparing FB with 10.9 Mg·ha-1PL, the yields were equal. Plant P and K concentrations were increased linearly by PL rate. There were no differences in % N or mg·kg-1Ca and Mg. The highest soil N03-N concentrations in the 15- to 30-cm depth range were produced by 43.6 Mg·ha-1PL (15 mg·kg-1 and FB (35 mg·kg-1. Only the high litter rate increased soil NO3-N below 30 cm As PL rate increased, there was a corresponding increase in soil P. There was a linear increase in soil K from 60 to 200 mg·kg-1 as rate increased. A linear decrease in pH was noted when PL rate increased. Soil EC was almost 2 times higher in the 43.6 Mg·ha-1 PL plots than the next highest rate (275 vs. 150 umhos·cm-1).

SO 2-induced growth reductions and sulphur accumulation in wheat

Ten open-top chambers were used to obtain SO 2 concentration-response relationships for growth in wheat cv. Banks, and to study the associated sulphur accumulation. Two-week-old seedlings were exposed to 0·004, 0·042, 0·121, 0·256 or 0·517 μl litre −1 SO 2 for 79 days, 4 h per day. Response variables measured included height, shoot weight, development stage, tiller number, ear weight per plant, average ear weight, total ear number and shoot sulphur concentration. All growth parameters were significantly negatively affected by SO 2 concentrations above and including 0·042 μl litre −1. A highly significant positive correlation existed between shoot sulphur concentration and ambient SO 2 concentration.

Establishment and Damage of the Sugarcane Borer (Lepidoptera: Pyralidae) in Corn as Influenced by Plant Development

Infestations of Diatraea saccharalis (F.) on corn caused significant yield reductions ( P < 0.05) averaging 11.8, 9.9, and 14.1% per established larva per plant when infestations were initiated at early-whorl, midwhorl, and early-tassel stages of development, respectively. Although losses mainly were attributable to reductions in average ear weight, this response appears to have been caused by different types and combinations of injury in each case, i.e., stalk tunnelling for the early-whorl infestation, stalk and ear feeding for the midwhorl infestation, and ear feeding for the early-tassel infestation. Intraplant movement and feeding site selection were influenced both by plant development and by late-stage larval behavior. Most larval mortality occurred within the first 4 days after infestations, with survival stabilizing by day 9. Results indicate that tightly appressed upper leaf sheaths on the corn plant offer greater resistance ( P < 0.05) to larval establishment than do leaf sheaths at and below the ear.

Seasonal Anhydrous Ammonia Comparison for Corn With and Without a Nitrification Inhibitor1

AbstractWith increased interest in “off‐season” N application and emphasis on better management of N with respect to environmental pollution and economic considerations, information is needed relative to seasonal anhydrous ammonia comparisons for corn with and without an inhibitor.Field studies compared rates of N applied preplant with December application either with or without the nitrification inhibitor, N‐SERVE (2‐chloro‐6‐(trichloromethyl) pyridine), to corn (Zea mays L.) on a Coastal Plain soil. The nitrification inhibitor (NI) did not affect yield, number of ears, average ear weight, and percent N, P, K, Ca, and Mg in the tissue or concentrations of various other elements in tissue sampled early in the growing season, at early silking, or in corn grain. Both low (90 kg/ha) and high (180 kg/ha) N levels increased yields above check plots (zero N) when applied in December for the three‐year average but both levels were significantly less than the high N level applied preplant. Ears per plant and ear weight were closely related to yields. Yield was more closely related to percent N in the tissue sampled at silking than tissue sampled early (ca 20‐cm height) or percent N in the grain.On a 3‐year average, the low and high N rates applied in December were 84 and 82% as efficient as preplant applications.These studies indicate that “off‐season” N applications as anhydrous ammonia are not as efficient as preplant applications. The NI did not influence micronutrient levels in the plant tissue, although N rates and time of application affected Mn, Fe, and Zn levels.

Effect of Plant Population and Rates of Fertilizer Nitrogen on Average Weight of Ears and Yield of Corn in the South1

SynopsisOn Dewey silt loam (pH 6.8, high in available P and exchangeable K) average ear weight of corn decreased from 7.6 ounces at plant population of 6,000 to 6.4 and 4.8 for populations of 12,000 and 18,000 respectively. N fertilizer significantly increased corn yield, but with little or no increase above 40 pounds per acre with any plant population. The 12,000‐populations showed overall increases, including no nitrogen treatment, of 10.3 and 13.8 bushels per acre over the 18,000 and 6,000 plant populations.