EFFECT OF SIMULATED FROST INJURY INDUCED BY PARAQUAT ON KERNEL GROWTH AND DEVELOPMENT IN CORN

1980 ◽  
Vol 60 (2) ◽  
pp. 419-426 ◽  
Author(s):  
D. J. MAJOR
Keyword(s):  
Moisture Content ◽  
Zea Mays L ◽  
Test Weight ◽  
Moisture Loss ◽  
Yield Reduction ◽  
Degree Days ◽  
Frost Injury ◽  
Yield Test ◽  
Kernel Growth ◽  
Period Duration

Four corn (Zea mays L.) hybrids, grown at Lethbridge, Alberta, in 1975, 1976, and 1977, were sprayed on three dates with paraquat in an attempt to produce symptoms similar to those of a first killing frost. Interactions among hybrids and treatments were rare for characteristics such as grain yield, test weight, and kernel moisture content. The most pronounced effect of paraquat was that yield was reduced by about 1000 kg/ha for each week the simulated frost occurred before maturity. Development was affected less than yield. Treatments that resulted in a yield reduction of 60% only caused a 15% reduction in test weight. Kernel development was closely related to the accumulation of growing degree days with a base of 12 °C. Kernel moisture content was higher immediately after paraquat treatment, but rate of moisture loss was also slightly higher so that the paraquat treatments caught up to the checks and finally had a slightly lower moisture content. The earlier the paraquat treatment was imposed, the greater was the reduction in growth rate of grain. In addition, a very early paraquat treatment resulted in a longer effective filling period duration (EFPD), and a later imposition of the paraquat treatment caused a reduction in the EFPD compared to the check treatments.

Seeding-date effects on yield, quality and maturity of safflower

1994 ◽  
Vol 74 (2) ◽  
pp. 261-266 ◽  
Author(s):  
H.-H. Mündel ◽  
R. J. Morrison ◽  
R. E. Blackshaw ◽  
T. Entz ◽  
B. T. Roth ◽  
...  
Keyword(s):  
Oil Content ◽  
Carthamus Tinctorius ◽  
Test Weight ◽  
Yield Reduction ◽  
Degree Days ◽  
Seeding Date ◽  
Early Maturing ◽  
Yield Quality ◽  
Maturity Degree ◽  
Accumulated Degree Days

Experiments were conducted for 4 yr at Lethbridge and Brooks, Alberta, and at Morden, Manitoba, to determine the effect of seeding date, cultivar (Saffire, S-208 and Cargill-3) and location on safflower (Carthamus tinctorius L.) yield, oil content, test weight and maturity; and the effect of accumulated degree–days (DD) on yield, oil content and test weight. The early-maturing cultivar, Saffire, produced the least variable yields across seeding dates. For locations and years where fall frosts did not occur before maturity, Cargill-3 produced good yields, even with late seeding; S-208 yielded less in similar situations; however, S-208 generally outyielded Saffire. Highest yields were obtained at Brooks by seeding in late April, at Lethbridge, by seeding in late April or early May. However, at both Alberta locations, Saffire could usually be seeded to mid-May without major yield reduction. At Morden, seeding during the third week of May provided optimum yields. Seeding date had little influence on oil content. Later seeding dates tended to reduce days to maturity and test weight. Safflower matured 3 wk earlier at Morden (earliest site) than at Lethbridge (latest site), with maturity at Brooks averaging 4–8 days earlier than at Lethbridge. Plants required more DD to reach maturity at Morden than at either Alberta location. DD was positively associated with yield of S-208 at both Lethbridge and Morden; for Saffire, only at Lethbridge; and for Cargill-3, only at Morden. DD generally did not significantly affect oil or test weight. Key words: Safflower, Carthamus, agronomy, seeding dates, yield, oil, test weight, maturity, degree–days

scholarly journals PREDICTION OF THE MOISTURE CONTENT OF EASTERN CANADIAN CORN USING MEASUREMENTS OF CAPACITANCE AND TEST WEIGHT

1989 ◽  
Vol 69 (1) ◽  
pp. 109-119
Author(s):  
J. C. BABB ◽  
C. J. DEMPSTER ◽  
R. J. WALLIS
Keyword(s):  
Zea Mays ◽  
Moisture Content ◽  
Regression Model ◽  
Zea Mays L ◽  
Test Weight ◽  
Coefficient Of Determination ◽  
Statistical Regression ◽  
Conversion Table ◽  
Grain Moisture ◽  
The Difference

A statistical regression model for rapid prediction of moisture content based on measurements of dielectric capacitance and test weight was developed for eastern Canadian corn (Zea mays L.). For 336 samples of the 1986 crop, dielectric readings were determined with a Model 919 grain moisture meter, test weight values with an Ohaus half-litre measure and moisture content values by a single-stage air-oven procedure. The regression model, which incorporates linear terms for dielectric reading and test weight plus an interaction term which is a product of the two, is an excellent predictor of corn moisture as indicated by analysis of the residuals and by the high value of the coefficient of determination (R2 = 0.95) and low value of the standard error of estimate (SEE = 0.85). Although the relationship between moisture content and dielectric reading for Ontario samples differed from that for Quebec samples, the proposed regression model helped to compensate for the difference. This model was also effective in predicting moisture content for 365 samples of 1987-crop eastern Canadian corn. As well, it yielded a better fit to 1986–1987 crop data than did the dielectric-based regression model used in CGC Corn Moisture Conversion Table No. 9.Key words: Zea Mays L., predicting corn moisture, Model 919 meter, capacitance, test weight, dielectric

scholarly journals Determining factors of test weight in maize (Zea mays L.)

2007 ◽  
pp. 40-42
Author(s):  
Zoltán Bódi ◽  
Pál Pepó
Keyword(s):  
Moisture Content ◽  
Zea Mays L ◽  
Fungal Infections ◽  
Test Weight ◽  
Hybrid Testing ◽  
Maize Production ◽  
Current State ◽  
Determining Factors ◽  
Higher Temperature ◽  
Lower Test

Most domestic maize production products are sold on markets abroad. Among the increasingly restrictive quality requirements, the demand for the measurement of test weight has also appeared. This measurement is not unfamiliar in the case of other cereals, such as wheat and barley, but it has not been applied widely in maize. It is likely for this reason that we have such little information and research available on this topic. In this study, we show the current state of this field with references from domestic and international literature.The density of maize is the weight of a particular volume and the most frequent unit is the test weight (kg/hl). This physical quality factor plays important roles in the storage, transport and mill industries. The value of test weight is influenced by many factors. The most important ones are the moisture content of grains, drying temperature, drought, precipitation, early frost, and the hybrid characters of a given genotype (grain type, FAO number). In general, the grain with higher moisture content has lower test weight and the higher temperature during (above 82°C) desiccation also leads to unfavourable values. Factors such as a drought interval after flowering, early frost in the case of hybrids with higher FAO numbers, injuries by insects, as well as fungal infections also influence the structure and moisture content of the maize grain.In the future, broader studies (hybrid testing, application of new agrotechnical elements) will be needed for understanding of the factors effecting test weight.

scholarly journals Characterization of Maize Genotypes (Zea mays L.) for Resistance to Striga asiatica and S. hermonthica and Compatibility with Fusarium oxysporum f. sp. strigae (FOS) in Tanzania

Agronomy ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1004
Author(s):  
John Lobulu ◽  
Hussein Shimelis ◽  
Mark D. Laing ◽  
Arnold Angelo Mushongi ◽  
Admire Isaac Tichafa Shayanowako
Keyword(s):  
Grain Yield ◽  
Fusarium Oxysporum ◽  
Biocontrol Agent ◽  
Zea Mays L ◽  
Control Treatment ◽  
Yield Reduction ◽  
Maize Genotypes ◽  
Significant Yield ◽  
The Mean

Striga species cause significant yield loss in maize varying from 20 to 100%. The aim of the present study was to screen and identify maize genotypes with partial resistance to S. hermonthica (Sh) and S. asiatica (Sa) and compatible with Fusarium oxysporum f. sp. strigae (FOS), a biocontrol agent. Fifty-six maize genotypes were evaluated for resistance to Sh and Sa, and FOS compatibility. Results showed that FOS treatment significantly (p < 0.001) enhanced Striga management compared to the untreated control under both Sh and Sa infestations. The mean grain yield was reduced by 19.13% in FOS-untreated genotypes compared with a loss of 13.94% in the same genotypes treated with FOS under Sh infestation. Likewise, under Sa infestation, FOS-treated genotypes had a mean grain yield reduction of 18% while untreated genotypes had a mean loss of 21.4% compared to the control treatment. Overall, based on Striga emergence count, Striga host damage rating, grain yield and FOS compatibility, under Sh and Sa infestations, 23 maize genotypes carrying farmer preferred traits were identified. The genotypes are useful genetic materials in the development of Striga-resistant cultivars in Tanzania and related agro-ecologies.

EFFECTS OF TEMPERATURE ON RATE AND DURATION OF KERNEL DRY MATTER ACCUMULATION OF MAIZE

1988 ◽  
Vol 68 (4) ◽  
pp. 935-940 ◽  
Author(s):  
M. TOLLENAAR ◽  
T. W. BRUULSEMA
Keyword(s):  
Growth Rate ◽  
Zea Mays ◽  
Dry Matter ◽  
Zea Mays L ◽  
Dry Weight ◽  
Controlled Environment ◽  
Dry Matter Accumulation ◽  
Linear Kernel ◽  
Effects Of Temperature ◽  
Kernel Growth

The response of rate and duration of kernel dry matter accumulation to temperatures in the range 10–25 °C was studied for two maize (Zea mays L.) hybrids grown under controlled-environment conditions. Kernel growth rates during the period of linear kernel growth increased linearly with temperature (b = 0.3 mg kernel−1 d−1 °C−1). Kernel dry weight at physiological maturity varied little among temperature treatments because the increase in kernel growth rate with increase in temperature was associated with a decline in the duration of kernel growth proportional to the increase in kernel growth rate.Key words: Zea mays L, period of linear kernel dry matter accumulation, controlled-environment conditions, kernel growth rate

Ear moisture during kernel development as influenced by field and laboratory selection

1995 ◽  
Vol 75 (3) ◽  
pp. 557-563 ◽  
Author(s):  
H. Z. Cross
Keyword(s):  
Moisture Content ◽  
Field Study ◽  
Agronomic Traits ◽  
Grain Filling ◽  
Kernel Weight ◽  
Test Weight ◽  
Mass Selection ◽  
Dry Matter Accumulation ◽  
Drying Characteristics ◽  
Laboratory Selection

Grain quality, timeliness of harvest, and profitability can be increased by improving field drying characteristics of maize (Zea mays L.) hybrids. To better understand hows genes control ear drying, I compared maize strains developed by divergently selecting three cycles for (1) high HM or low LM moisture content at 45 d post pollination in the field or (2) fast FD vs. slow ear drying SD In laboratory. A field study across five locations compared HM, LM, FD, and SD strains from each of five synthetics for grain yield, ear moisture at harvest, test weight, lodging, and other agronomic traits. I studied ear moisture during grain filling for two subsets of divergently selected strains from one and three synthetics for 2 yr. In a third 2-yr field study, I measured mature kernel weight, lag period duration (LPD), effective grain-filling period (EFPD), and rate of dry matter accumulation (RDMA) for LM and HM strains developed from each of four synthetics. When averaged across the five synthetics, both SD and LM selections produced equivalent yields but lower ear moisture at harvest than the corresponding divergent strains. The LM strains had higher test weights than HM strains. When averaged across three synthetics and 2 yr, the HM strains produced higher moisture than LM strains at 15, 30, 45, and 60 d after silking. However, environments also influenced moisture content of the kernels during grain filling. In three of the four synthetics studied, HM strains had heavier kernels than corresponding LM strains. The heavier kernels seem to be due to increased RDMA. When averaged across four synthetics, LM strains had shorter LPD than HM strains. These correlated selection responses suggest that a genetic association exists among moisture content during grain filling, moisture content at physiological maturity, moisture content at harvest, LPD, and test weight. Breeding for LM or SD should improve field-drying characteristics of maize without increasing stalk breakage or decreasing yields. Key words:Zea mays L., grain filling, dry-down rates, mass selection, breeding methods

Triticale (X Triticosecale Wittmack) Response to Herbicides

1994 ◽  
Vol 8 (1) ◽  
pp. 119-123 ◽  
Author(s):  
Alan C. York ◽  
Stewart M. Turner ◽  
Ronald E. Jarrett
Keyword(s):  
Plant Height ◽  
Kernel Weight ◽  
Grain Weight ◽  
Test Weight ◽  
X Triticosecale ◽  
Affected Plant ◽  
Yield Test ◽  
Triticosecale Wittmack ◽  
X Triticosecale Wittmack

The response of ‘Florico,’ ‘Victoria,’ and 'Stan II’ triticale to 2,4-D, dicamba, 2,4-D plus dicamba, diclofop, and thifensulfuron plus tribenuron applied POST during the tillering stage was examined. At rates twice those recommended for application to wheat, Victoria and Stan II were not injured, and injury to Florico was less than 10%. None of the herbicides or combinations adversely affected plant height at maturity, tiller or spike production, grain weight/spike, kernel weight, kernels/spike, yield, or test weight of any cultivar. Cultivars varied in tiller production, height, yield, test weight, kernel weight, and kernels/spike.

scholarly journals Effect of Drying on the Rehydration Properties of Some Selected Shellfish

2020 ◽  
pp. 42-48
Author(s):  
D. B. Kiin-Kabari ◽  
N. Obasi
Keyword(s):  
Moisture Content ◽  
Proximate Composition ◽  
Crude Protein ◽  
Moisture Loss ◽  
Rehydration Ratio ◽  
Crude Fibre ◽  
Oven Drying ◽  
Water Imbibition ◽  
Nutritional Qualities ◽  
Sample Water

This study was conducted to evaluate the effect of oven drying on the proximate composition and rehydration characteristics of shellfish. Shellfish studied included rough and smooth periwinkle, oyster and whelk. Proximate composition of the fresh samples were determined. Then dried in the oven to a moisture content of 10% and further rehydrated with distill water in sample water ratio of 1:40 and allowed to equilibrate. Proximate composition of the fresh shellfish showed that moisture content ranged from 82.38 to 69.24% with fresh smooth periwinkle having the highest moisture value while whelk had the lowest. The results also showed that whelk had the highest values for ash (2.92%), crude protein (18.83%) and crude fibre (3.71%) when compared to other samples. On rehydration, a moisture loss of 11.75%, 13.28%, 19.24% and 22.04% were observed for rough periwinkle, smooth periwinkle, oyster and whelk, respectively. The results for rehydration indices revealed that dehydration ratio was significantly (p<0.05) high for whelk (1.44), followed by oyster (1.29), rough periwinkle (1.23) and lastly, smooth periwinkle 1.20. Rehydration ratio of whelk (1.47) was equally significantly higher, followed by oyster (1.33) and the least were rough and smooth periwinkle (1.17). For coefficient of reconstitution, oyster recorded the highest value of 1.03, followed by whelk 1.02, rough periwinkle 0.95 and smooth periwinkle 0.98. Rate of water imbibition revealed a sharp increase in the water content of smooth periwinkle up to 240 min and thereafter, it slowed down until equilibrium was reached. In terms of rough periwinkle, oyster and whelk; water imbibition took place with rehydration time up to 300 min, 210 min and 270 min, respectively, thereafter they slowed down. The results have demonstrated that the rate in which oven drying affect the physical and nutritional qualities of shellfish differs.

scholarly journals A Study on Factors Influencing the Determination of Moisture Content of Fibrous Peat

2011 ◽  
Vol 2 (2) ◽  
pp. 39-47 ◽  
Author(s):  
Pui Tau Shien ◽  
Seneviratne H.N. ◽  
Dygku Salma Awg Ismail
Keyword(s):  
Moisture Content ◽  
Particle Density ◽  
Peat Soil ◽  
Test Procedure ◽  
Field Measurements ◽  
Standard Test ◽  
Moisture Loss ◽  
Fibrous Peat ◽  
Saturated Sample

Fibrous peat is an undrained peat that usually possesses very high moisture content. However, not all experimental procedures are applicable for determination of moisture content of fibrous peat. This research is aimed at examining the determination of insitu moisture content of fibrous peat using field measurements. The peat soil samples were collected at shallow depths from Asajaya at Kota Samarahan and Taman Kopodims at Matang , Kuching Sarawak by using peat auger. The laboratory tests such as determination of moisture content, fiber content, particle density and ash content were conducted on the collected samples in order to establish relationships between the parameters. Undisturbed peat samples from Matang were subjected to falling head permeability test to determine the saturated permeability. The saturated sample were then allowed to drain freely to simulate the moisture loss possible during sampling when samples were brought out of boreholes. The test results showed that moisture content varies according to the drying temperature and position of the soil sample (top, middle and bottom) during sampling. Comparing samples from both locations, peat soil from Kota Samarahan possessed higher moisture content. The saturated permeability of peat sample was in the range of 2.62 – 3.05 cm/s. The free draining trial showed that moisture loss during sampling significantly influence the moisture content measurement. The variation in value of moisture content for fibrous peat may occurs due to several factors such as existing ground water table, sampling method by boring, existing standard test procedure which is not suitable for peat soils requirement and also because of the physical properties which varied according to depth of soil.

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