Some factors influencing electrolyte leakage from maize (Zea mays L.) kernels

1991 ◽  
Vol 1 (1) ◽  
pp. 15-20 ◽  
Author(s):  
H. Bruggink ◽  
H. L. Kraak ◽  
M. H. G. E. Dijkema ◽  
J. Bekendam
Keyword(s):  
Zea Mays ◽  
Moisture Content ◽  
Electrolyte Leakage ◽  
Zea Mays L ◽  
Mechanical Damage ◽  
Kernel Weight ◽  
Conductivity Measurements ◽  
Factors Influencing ◽  
Quality Testing ◽  
Maize Kernels

AbstractEven though the embryo of a maize (Zea mays L.) kernel contributes relatively little to total kernel weight, it is a main source of electrolytes which leach from the kernel during imbibition. Ageing of maize kernels for 18 days at 40°C and a moisture content of about 15% results in an increase of electrolyte leakage which almost exclusively originates from the embryo. The effect of ageing is most apparent after prolonged periods of imbibition. Mechanical damage increases leakage early during imbibition, the effect of damage being considerably larger for aged than for unaged kernels. The large amount of electrolytes measured after the first hour of imbibition of undamaged kernels comes mainly from the pericarp. The electrolyte content of the pericarp is variety dependent and may interfere with quality testing by conductivity measurements.

GROWTH AND [14C] SUCROSE UPTAKE OF APICAL AND BASAL MAIZE KERNELS

1986 ◽  
Vol 66 (4) ◽  
pp. 863-869
Author(s):  
JONATHAN M. GREENBERG ◽  
TIM LLOYD SETTER
Keyword(s):  
Zea Mays ◽  
Liquid Scintillation ◽  
Zea Mays L ◽  
Dry Weight ◽  
Grain Filling ◽  
Kernel Weight ◽  
Sucrose Uptake ◽  
Sucrose Transport ◽  
The Difference ◽  
Maize Kernels

Kernels located near the apex of the ear of corn (Zea mays L.) are smaller and more likely to abort than basal kernels. Studies were conducted to evaluate the importance of time of pollination and rate of sucrose uptake in determining differences in mature kernel weight between apical and basal kernels. Simultaneous pollination of all florets in an ear did not reduce the difference in mature dry weight between apical and basal kernels or the incidences of sterility and abortion. The ability of developing apical and basal kernels to take up sucrose was evaluated by immersing the bases of detached kernels in 50 mM 14C-sucrose and measuring the incorporated radioactivity by liquid scintillation counting. Sucrose uptake increased during development, especially at the beginning of the linear phase of grain filling. Differences in sucrose uptake rate were insufficient to explain the differences between apical and basal kernels in dry weight.Key words: Carbohydrate, partitioning, corn, sucrose transport, seed development, Zea mays L.

scholarly journals Excision Patterns of Activator (Ac) and Dissociation (Ds) Elements in Zea mays L.: Implications for the Regulation of Transposition

Genetics ◽  
1996 ◽  
Vol 144 (4) ◽  
pp. 1851-1869 ◽  
Author(s):  
Manfred Heinlein
Keyword(s):  
Zea Mays ◽  
Zea Mays L ◽  
Waxy Gene ◽  
Transposition Frequency ◽  
Cis Acting ◽  
Dosage Effects ◽  
In Trans ◽  
Ds Excision ◽  
Maize Kernels ◽  
Strong Contrast

The pattern of aleurone variegation of maize kernels carrying Ac and bz-m2(DI) as reporter allele for Ac activity depends on the dosage of both Ac and Ds. Alterations of Ac dosage can abolish Ds excision at certain times and allow it to occur at other times. wx-m7 and wx-m9 are different Ac insertions in the Waxy gene which have different dosage effects on Ds excision. Kernels, heterozygous for the two Ac alleles and being either wx-m7/wx-m7/wx-m9 or wx-m9/wx-m9/wx-m7 exhibit characteristic patterns of predominantly late excisions; this is in strong contrast to the pattern of early excisions present on wx-m7/wx-m7/wx-m7 homozygotes. This observation supports the hypothesis that the Ac alleles express different amounts of transposase (TPase) during development and that above a certain level of TPase transposition is inhibited. Furthermore, experimental results suggest that the frequency of Ac-induced events is influenced by the dosage and composition of the transactivated Ds or Ac allele. Thus, transposition frequency seems not to be exclusively determined in trans by the amount of active TPase, but also by specific cis-acting properties of the TPase substrate.

scholarly journals Aflatoxigenic contamination of freshly harvested white maize (Zea mays L.) from some selected Ugandan districts

2019 ◽  
Author(s):  
Timothy Omara
Keyword(s):  
Zea Mays ◽  
Moisture Content ◽  
Ochratoxin A ◽  
Zea Mays L ◽  
Lake Victoria ◽  
Total Aflatoxin ◽  
Strategic Adaptation ◽  
Maize Varieties ◽  
Agroecological Zones

The moisture content and total aflatoxin (AF) content of 27 samples of freshly harvested white maize (Zea mays L.) from Mubende (n = 3), Ibanda (n = 3), Jinja (n = 3), Mayuge (n = 3) , Buikwe (n = 3), Hoima (n = 3), Mpigi (n = 3), Masindi (n = 3) and Bugiri (n = 3) districts of Uganda representing the agroecological zones: Lake Victoria crescent, Western Highlands, South East and Lake Albert Crescent were determined in the second season harvest of January 2019 to March 2019. Moisture content ranged from 12.9 to 18.8% (mean moisture content varied from 13.9±0.35-17.2±1.55%) with the highest moisture recorded in maize from Ibanda. The highest mean AF contamination of 11.0±3.01 μg/kg was recorded in maize from Hoima while the lowest AF content of 3.8±1.30 μg/kg was recorded in maize from Mpigi. Despite the fact that all the samples had detectable aflatoxins, none of the maize samples had aflatoxin greater than WHO regulatory limit of 20 μg/kg. White maize in Uganda are precontaminated by aflatoxins prior to harvest. Whereas the spectre of aflatoxigenic contamination of foods remains a ticklish challenge to address, strategic adaptation and deployment of appropriate interventions can help secure a safe harvest. Farmers should plant maize varieties with established maturity periods to ensure timely harvesting. Further research should assess the presence of other mycotoxins as zearalenone, sterigmatocystin, ochratoxin A, citrinin, vomitoxin and diacetoxyscirpenol that may co-occur with aflatoxins in freshly harvested maize.

scholarly journals Karakteristik Pengeringan Biji Jagung (Zea Mays L.) Menggunakan Alat Pengering Surya Adriyarkara Termodifikasi

2018 ◽  
Vol 3 (2) ◽  
pp. 351-360
Author(s):  
Athul Fadhli ◽  
Diswandi Nurba ◽  
Raida Agustina
Keyword(s):  
Zea Mays ◽  
Relative Humidity ◽  
Moisture Content ◽  
Zea Mays L ◽  
Initial Moisture Content ◽  
Solar Irradiation ◽  
Air Velocity ◽  
Drying Time ◽  
Average Temperature ◽  
Average Relative Humidity

Abstrak. Jagung merupakan tanaman penghasil karbohidrat terpenting. Pengeringan jagung pipil menggunakan alat pengering merupakan proses untuk menghasilkan jagung pipil yang siap diolah untuk pembuatan tepung jagung dengan batas kadar air tertentu sehingga menghaslkan jagung pipil dengan kualitas yang baik. Tujuan penelitian ini adalah untuk mengkaji karakteristik pengeringan biji jagung menggunakan alat pengering surya Termodifikasi. Metode penelitian  menggunakan 3,15 kilogram jagung pipil dengan kadar air awal 22% untuk proses pengeringan. Parameter yang dianalisis terkait alat pengering kolektor surya yaitu temperatur, kelembaban relatif, kecepatan udara dan iradiasi surya, sedangkan parameter yang dianalisis terkait bahan yaitu kadar air, lama waktu pengeringan, laju pengeringan dan organoleptik. Prosedur penelitian terdiri dari pengujian kosong dan pengujian dengan menggunakan jagung pipil. Hasil penelitian menunjukkan bahwa temperatur rata-rata dalam rak pengering sebelum dilakukan modifikasi yaitu 44,4oC, temperatur rata-rata setelah dilakukan modifikasi yaitu 55,5oC dan temperatur rata-rata rak pengering pada pengeringan menggunakan jagung pipil yaitu 46,96oC. Kelembaban relatif rata-rata dalam rak pengering sebelum dilakukan modifikasi yaitu 40,1%, kelembaban relatif rata-rata dalam rak pengering setelah modifikasi yaitu 35,1% dan kelembaban relatif rata-rata pengeringan menggunakan jagung pipil yaitu 44,45%. Dari hasil pengukuran tersebut menunjukkan bahwa nilai temperatur dan kelembaban pada alat setelah modifikasi lebih baik dibandingkan sebelum alat dimodifikasi. Pengukuran temperatur dan kelembaban relatif terdiri dari 4 titik pengukuran yaitu rak 1A,1B dan rak 2A, 2B. Kecepatan udara rata-rata yang diukur konstan yaitu 0,7 m/s pada ruang pengering, sedangkan lingkungan 1,1 m/s. Total iradiasi surya selama pengeringan yaitu 1848,84 W/m2. Kadar air jagung pipil masing-masing rak yaitu rak 1A 14,29%, rak 1B 14,47%, rak 2A 13,91% dan rak 2B 14,1%. Hasil dari pengujian organoleptik, panelis agak menyukai jagung pipil yang dikeringkan menggunakan alat pengering tersebut.Characteristics of Seed Drying (Zea mays L.) Using a Modified Adriyarkara Solar DryerAbstract. Corn is the most important carbohydrate plant. Drying corn using a drying tool is a process to produce corn that are ready to be processed for making corn flour with a certain water content limit so as to produce corn with good quality. The purpose of this study was to examine the characteristics of drying of corn kernels using a modified solar dryer. The research method used 3,15 kilogram of corn milled with the initial moisture content of 22% for drying process. The parameters analyzed in relation to solar collector dryers are temperature, relative humidity, air velocity and solar irradiation, while the parameters analyzed are materials such as moisture content, drying time, drying rate and organoleptic. The research procedure consists of unloaded testing and testing using corn. The results showed that the average temperature in the dryer tray before modification was 44,4°C, the average temperature after modification was 55,5°C and the average temperature of the dryer tray on drying using corn was 46,96oC. The average relative humidity in the dryer tray before modification is 40,1%, the average relative humidity in the dryer tray after modification is 35,1% and the average relative humidity of drying using corn is 44,45%. From the measurement results show that the value of temperature and humidity in the tool after modification is better than before. Measurement of temperature and relative humidity consist of 4 point of measurement that is tray 1A, 1B and tray 2A, 2B. Average mean air velocity measured is 0,7 m/s at the dryer room, while the environment is 1,1 m/s. Total solar irradiation during drying is 1848,84 W/m2. Moisture level of corn each shelves tray 1A is 14,29%, tray 1B is 14.47%, tray 2A is 13,91% and tray 2B is 14,1%. As a result of organoleptic testing, panelists rather like dried corn using the dryer.

scholarly journals The Genetic Architecture of Maize (Zea mays L.) Kernel Weight Determination

2014 ◽  
Vol 4 (9) ◽  
pp. 1611-1621 ◽  
Author(s):  
S. Alvarez Prado ◽  
C. G. Lopez ◽  
M. L. Senior ◽  
L. Borras
Keyword(s):  
Zea Mays ◽  
Genetic Architecture ◽  
Zea Mays L ◽  
Kernel Weight

scholarly journals PERBEDAAN KARAKTERISTIK KIMIA DAN DAYA CERNA PATI TEPUNG JAGUNG DAN TEPUNG KECAMBAH JAGUNG (Zea mays L.)

2018 ◽  
Vol 7 (1) ◽  
pp. 43
Author(s):  
Willem Kurniawan Lombu ◽  
Ni Wayan Wisaniyasa ◽  
AAI. Sri Wiadnyani
Keyword(s):  
Zea Mays ◽  
Chemical Composition ◽  
Moisture Content ◽  
Zea Mays L ◽  
Starch Content ◽  
Fat Content ◽  
Ash Content ◽  
Starch Digestibility ◽  
Corn Flour ◽  
The Difference

This study aims to determine the difference of characteristic and starch digestibility of germinated and ungerminated flour. This study used randomized complete design (RCD) three repeated. The corn germinated for 36 hours. Corn germinated flour and ungerminated flour were evaluated directly of the chemical composition of the flour content, moisture content, ash content, protein, fat, carbohydrates, fiber, starch content and starch digestibility. The results showed the corn germinated flour has increased of moisture content from 9.66% into 10.38%, increased of protein into 7.22% into 8.45%, increased of fiber content from 2.28% into 2.79% and increased of starch digestibility from 57.04% into 62.43%. While were the decreased fat content from 5.17% into 4.76%, decreased of carbohydrate from 75.41% into 73.89% and decreased of starch content from 76.10% into 69.40%. The treatmented has no effect for the flour content decreased from 41.40% into 40.36% and ash content decreased from 2.52% into 2.51%. Germinated increased starch digestibility and changed the character of corn flour.

Cross-pollination effects on maize (Zea mays L.) hybrid yields

1992 ◽  
Vol 72 (1) ◽  
pp. 27-33 ◽  
Author(s):  
R. T. Weiland
Keyword(s):  
Zea Mays ◽  
Zea Mays L ◽  
Grain Filling ◽  
Maize Yield ◽  
Kernel Weight ◽  
First Year ◽  
Kernel Number ◽  
Cross Pollination ◽  
Grain Filling Period ◽  
N Fertility

Recent studies have shown that pollen from a long-season maize (Zea mays L.) hybrid increased yield of a short-season hybrid by lengthening the effective grain-filling period, while the reciprocal cross did not alter this period or yield. This effect (metaxenia) was evaluated further in the studies reported here with hybrids of more diverse maturity and under both high and low N fertility. In the first year of this study (1989), sib- and cross-pollinations were made among B73Ht × Mo17 (B × 7) and two early-silking hybrids, LH59 × LH146 (L × 6) and Pioneer 3732 (3732) under N-sufficient (275 kg ha−1) and two lower N regimes (17 and 67 kg ha−1). Only a few significant effects were observed and these were noted at high N with one exception. With 3732 pollen, grain yield of B × 7 was decreased at 275 kg N ha−1, and physiological maturity occurred 3 d earlier. Yield of 3732 was increased by L × 6 pollen in comparison with B × 7 pollen. Kernel number and average kernel weight were not altered by pollen source. Pollen type did not affect yields under low N fertility, except for a reduction when B × 7 was pollinated by L × 6 at the 67-kg N ha−1 rate. In 1990, under N-sufficient fertility, B73Ht × LH156 (B × 6), a late-silking hybrid, and LH146 × LH82 (L × 2), an earlier hybrid, were sib- and cross-pollinated with B × 7 and 3732. The only significant effect observed was that L × 2 pollen increased B × 6 yield. Thus with the hybrids used, yields of early-season types were not altered by cross-pollination with long-season types. Previous results showing increased yields when 3732 was pollinated by B × 7 were not duplicated in either year, suggesting metaxenia effects are highly dependent upon environment.Key words: Metaxenia, xenia, cross-pollination, maize, yield, N levels

scholarly journals Maize (Zea Mays L) landraces from the southern region of Brazil: contamination by Fusarium sp, zearalenone, physical and mechanical characteristics of the kernels

2009 ◽  
Vol 52 (spe) ◽  
pp. 11-16 ◽  
Author(s):  
Tatiana Roselena de Oliveira ◽  
David de Souza Jaccoud-Filho ◽  
Luciana Henneberg ◽  
Milton Domingos Michel ◽  
Ivo Mottin Demiate ◽  
...  
Keyword(s):  
Zea Mays ◽  
Mechanical Characteristics ◽  
Zea Mays L ◽  
Southern Region ◽  
Fusarium Sp ◽  
Maize Kernels ◽  
Physical And Mechanical Characteristics

This work had as objectives the study of the physical and mechanical characteristics of maize kernels in relation to the contamination by Fusarium sp and by zearalenone in twenty landraces of maize from the southern region of Brazil. From the analyzed samples, 60 % has been considered to have a hard endosperm type and 40 % an intermediary one. A correlation between the physical and mechanical variables was observed as an indication that the higher is the proportion of hard endosperm, more dense will be the kernel and more force for its rupture will be necessary. The level of contamination by Fusarium sp was between 5.5 and 24.75% among the analyzed grains, correlating positively with the flotation index, indicating that the landraces of maize with a softer endosperm can present a higher contamination by this genus. The presence of zearalenone was verified in 75 % of the samples, in concentrations varying from 50 to 640 µg kg-1.

Biplot analysis for multi-environment trials of maize (Zea mays L.) hybrids in Iran

2010 ◽  
Vol 61 (9) ◽  
pp. 700 ◽  
Author(s):  
Saeed Safari Dolatabad ◽  
Rajab Choukan ◽  
Eslam Majidi Hervan ◽  
Hamid Dehghani
Keyword(s):  
Zea Mays ◽  
Grain Yield ◽  
Zea Mays L ◽  
Kernel Weight ◽  
Yield Stability ◽  
Grain Number ◽  
Maize Hybrids ◽  
Biplot Analysis ◽  
Ear Height ◽  
Two Sectors

Adapted maize (Zea mays L.) hybrids should be identified and chosen based on multi-environment trials analysing several traits. The objectives of this study were to identify mega-environments and suitable adapted maize hybrids based on both mean grain yield and grain yield stability and were to evaluate the 14 maize hybrids based on several desirable traits. Biplot analysis determined one mega-environment and two sectors that consist of one location in each sector for maize in Iran. The mega-environment included Kerman (KRM), Kermanshah (KSH), Moghan (MGN), Dezfol A (DZF A), Karaj (KRJ), Darab (DRB), Dezfol B (DZF B), Shiraz B (SHZ B), and Esfahan (ESF), where hybrid OSSK 602 was the best performing hybrid. The first sector included Khoramabad (KHM) where BC 678 was the best hybrid, and the second sector included Shiraz A (SHZ A) where ZP 599 was the hybrid with the highest performance. OSSK 602 was the best hybrid among all of the studied hybrids followed by ZP 677 and ZP 684. The genotype × trait biplot indicated that ZP 677 and OSSK 602 had greater thousand-kernel weight and grain number, whereas ZP 684 had longer day to maturity and larger cob diameter. KSC 700, KSC 704, and BC 678 had higher ear height and more days to tasseling than other hybrids. The genotype × trait biplot graphically displayed the interrelationships among traits and it was used in identifying hybrids that are good for some particular traits.

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