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Effects of winter wheat season tillage on soil properties and yield of summer maize
2017
Yunqi WANG | Yinghua ZHANG | Zhimin WANG | Hongbin TAO | Shunli ZHOU | Pu WANG
The North China Plain (NCP) serves as China's second most important maize production region. Rotary tillage, a popular method used in winter wheat/summer maize systems in the region, has adverse effects on maize production. The current study was conducted to determine whether rotary tillage after subsoiling in the winter wheat season (RS) improves the grain-filling rate and yield of summer maize by decreasing soil bulk density, when compared with rotary tillage (R), in the NCP. The RS treatment decreased soil bulk density and increased soil moisture in the summer maize season when compared with the R treatment. Root number under the RS treatment at 8 collar and silking stages was 22.4-35.3% and 8.0-11.7% greater than under the R treatment, respectively. The RS treatment significantly enhanced the grain-filling rate and grain weight as compared to the R treatment. Yield, thousand grain weight, biomass, and harvest index under the RS treatment were 7.7, 7.2, 2.3 and 5.3% higher than under the R treatment. Thousands grain weight was correlated with soil bulk density and soil moisture after silking. Consequently, the increase in grain weight and yield of summer maize resulted from the decrease in soil bulk density and a consequent increase in soil moisture, root number and grain-filling rate.
Показать больше [+] Меньше [-]Effect of the dough mixing process on the quality of wheat and buckwheat proteins
2017
Marcela Sluková | Julie Levková | Alena Michalcová | Šárka Horáčková | Pavel Skřivan
The changes in the structure of cereal proteins during the mixing of flour into dough was described and evaluated. Wheat gliadins and glutenins (gluten proteins) have unique physical properties and play an important role in breadmaking. The effect of mixing time on the formation and the structure of the gluten network was determined using scanning electron microscopy (SEM). Buckwheat flour (gluten-free) was used to compare the development of structure during the mixing process.
Показать больше [+] Меньше [-]Influence of germination temperatures on the chemical composition of wheat (Triticum aestivum L.) seeds
2017
František Hnilička | Alena Hejtmánková | Matyáš Orsák | Helena Hniličková
The content of saccharides and lipids in wheat seeds from both conventional and organic agriculture was determined based on the length of germination (0, 2, or 5 days) and germination temperature (10 and 22°C). The content of saccharides was determined by HPLC, and the total lipid content was detected by Soxhlet extraction in the course of germination. While the non-germinated seeds had the highest content of glucose (6.95 mg/g) and fructose (4.37 mg/g), in conventionally grown seeds sucrose (5.03 mg/g) and maltose (3.62 mg/g) were at the highest level. In organically and conventionally produced seeds the contents of fructose, glucose, and maltose increased due to germination. While the content of lipids increased in the seeds from organic production on the second day from 0.46 g/10 g to 0.51 g/10 g (at 10°C) and 0.64 g/10 g (at 22°C). Differences in the content of saccharides and lipids between seeds from organic and conventional agriculture were not unequivocally confirmed.
Показать больше [+] Меньше [-]Effects of maize and winter wheat grown under different cultivation techniques on biological activity of soil
2017
Karolina FURTAK | Karolina GAWRYJOŁEK | Anna M. GAJDA | Anna GAŁĄZKA
The aim of the study was to compare the activity and functional biodiversity in soil under two different cereals: common maize and winter wheat, both grown in the same pattern of cultivation techniques: conventional (to 25 cm depth) and reduced (to 10 cm depth). Soil samples for comparative analysis were collected at the same time (July 2016) at a long-term field experiment, which was carried out in 2013-2016. Soil biological activity was determined by measurement of dehydrogenases activity (DHa) with TTC (2,3,5-triphenyltetrazolium chloride) application, microbial biomass carbon (MBC) and nitrogen (MBN) content by fumigation-extraction method, and functional diversity of soil microorganisms using the Biolog EcoPlate System. The results demonstrated that the cultivation technique had a greater impact on the soil biological activity, compared to the type of cereal. Higher biological activity was found in the soil under reduced tillage in both cereals. Calculated correlations showed that DHa, MBC, MBN and acid phosphatases were positively correlated with each other. The negative correlation obtained between yield and biological parameters of activity in soil was not expected.
Показать больше [+] Меньше [-]Untold stories | Forty years of field research on root diseases of wheat
2017
Cook, R. James
Quality Variation of Domestic Wheat Compared to Imported Wheat Depending on Harvest Year
2017
Kwak, H.S., Korea Food Research Institute, Wanju, Republic of Korea | Kim, T.J., CJ Cheiljedang, Republic of Korea | Joo, E.Y., CJ Cheiljedang, Republic of Korea | Cha, J.H., CJ Cheiljedang, Republic of Korea | Kim, A.J., CJ Cheiljedang, Republic of Korea | Kim, M.J., Korea Food Research Institute, Wanju, Republic of Korea | Kim, S.S., Korea Food Research Institute, Wanju, Republic of Korea
Quality characteristics (moisture, protein, ash, bulk density, falling number, damaged kernel, and foreign material) of 443 domestic wheat samples harvested between 2011 and 2013 were compared with those of 160 imported wheat samples from the United States, Australia, and Canada. Moisture content of domestic wheat (10.9~13.9%) was generally higher than that of imported wheat (8.0~12.6%). Large variation in protein content was found in domestic wheat compared to imported wheat even though variation in protein content of domestic wheat tended to decrease every year, implying quality control efforts for domestic wheat. A similar trend was observed in ash content, which was approximately 0.1% higher in domestic wheat kernels over 3 years. Imported wheat samples had a falling number of 300 or above. On the other hand, some domestic wheat samples had a falling number of 300, which meant low quality of wheat kernels. Generally, quality variations in domestic wheat kernels decreased over the years; however, it is necessary to maintain minimum requirements of moisture content and falling number for high and consistent quality domestic wheat.
Показать больше [+] Меньше [-]The Impact of the Kansas Wheat Breeding Program on Wheat Yields, 1911–2006
2017
Nalley, Lawton Lanier | Barkley, Andrew P. | Chumley, Forrest G.
This paper quantifies advances of the Kansas Agricultural Experiment Station (KAES)wheat breeding program for two time periods: (1) 1911 to 2006 and (2) 1977 to 2006. Usingmultiple regression, increases in yields of wheat varieties grown in Kansas are quantified,holding growing conditions and other improvements in productivity constant. Differencesin KAES variety yields and those released by other public and private breeders arequantified. During the ‘‘new age’’ of wheat breeding (1977–2006), wheat breeding alone isfound to have increased yields by 6.182 bushels per acre, or an average increase of 0.206bushels per year.
Показать больше [+] Меньше [-]Apparent Coefficient of Friction of Wheat on Denim
2017
Schwab, Charles V.
Calculation of the extraction force for a grain entrapment victim requires a coefficient of friction between the grain and the surface of the victim. Because denim is a common fabric for the work clothes that cover entrapment victims, the coefficient of friction between grain and denim becomes necessary. The purpose of this research was to calculate the apparent coefficient of friction of wheat on denim fabric using a proven procedure. The expectation is to improve the current understanding of conditions that influence extraction forces for victims buried in wheat. The apparent coefficient of friction of wheat on denim fabric was calculated to be 0.167 with a standard deviation of ±0.013. The wheat had a moisture content of 10.7% (w.b.) and bulk density of 778.5 kg m-3. The apparent coefficient of friction of wheat on denim was not significantly affected by pull speeds of 0.004, 0.008, and 0.021 mm s-1 nor normal grain pressures of 3.2, 4.8, 6.3, 7.9, and 11.1 kPa. This is a beginning of understanding the conditions that influence the extraction forces for grain entrapment victims. Keywords: Farm safety, Grain entrapment, Grain rescue, Grain extraction.
Показать больше [+] Меньше [-]Effects of Wheat-Maize Intercropping on Population Dynamics of Wheat Aphids and Their Natural Enemies
2017
Liu, Junhe | Yan, Yan | ʻAlī, ʻĀbid | Wang, Ningtao | Zhao, Zihua | Yu, Mingfu
To study the effects of wheat-maize intercropping on the population dynamics of wheat aphids and their natural enemies, wheat-maize intercropping patterns were divided into four levels: 8:2, 6:2, and 4:2 intercropping, and monoculture wheat. The results showed that as the wheat coverage rate decreased, the quantities of immigrating winged aphids and their natural enemies significantly differed; the population densities of the natural enemies of wheat aphids continuously rose and reached the highest levels in the 4:2 intercropping. During the stable periods, the maximum population density of wheat aphids was the highest in monoculture wheat. With a reduction in the wheat coverage ratio, the maximum population density of wheat aphids showed a decreasing trend. The control imposed by predatory natural enemies in intercropped wheat was higher than that in monoculture wheat; it was strongest in the 8:2 intercropping and the lowest in wheat monoculture. With an increase in the proportion of wheat, the parasitism rate of parasitic wasps increased gradually and reached the highest level in 4:2 intercropping. The effect of host density on hyperparasitism was significant in the intercropped wheat. The intercropping pattern had a great effect on the wheat aphids’ natural enemies. In different agricultural landscapes, the diversity of wheat aphids’ natural enemies differed significantly between intercropped wheat and monoculture wheat; in the heterogeneous landscape, the natural enemy diversity was highest in intercropped wheat, and it was far higher than that in the other wheat cultivation patterns. The natural enemy diversity was also slightly different between monoculture wheat in the heterogeneous landscape and intercropped wheat in the homogeneous agricultural landscape.
Показать больше [+] Меньше [-]Effects of Wheat-Maize Intercropping on Population Dynamics of Wheat Aphids and Their Natural Enemies
2017
Junhe Liu | Yan Yan | Abid Ali | Ningtao Wang | Zihua Zhao | Mingfu Yu
To study the effects of wheat-maize intercropping on the population dynamics of wheat aphids and their natural enemies, wheat-maize intercropping patterns were divided into four levels: 8:2, 6:2, and 4:2 intercropping, and monoculture wheat. The results showed that as the wheat coverage rate decreased, the quantities of immigrating winged aphids and their natural enemies significantly differed: the population densities of the natural enemies of wheat aphids continuously rose and reached the highest levels in the 4:2 intercropping. During the stable periods, the maximum population density of wheat aphids was the highest in monoculture wheat. With a reduction in the wheat coverage ratio, the maximum population density of wheat aphids showed a decreasing trend. The control imposed by predatory natural enemies in intercropped wheat was higher than that in monoculture wheat: it was strongest in the 8:2 intercropping and the lowest in wheat monoculture. With an increase in the proportion of wheat, the parasitism rate of parasitic wasps increased gradually and reached the highest level in 4:2 intercropping. The effect of host density on hyperparasitism was significant in the intercropped wheat. The intercropping pattern had a great effect on the wheat aphids’ natural enemies. In different agricultural landscapes, the diversity of wheat aphids’ natural enemies differed significantly between intercropped wheat and monoculture wheat: in the heterogeneous landscape, the natural enemy diversity was highest in intercropped wheat, and it was far higher than that in the other wheat cultivation patterns. The natural enemy diversity was also slightly different between monoculture wheat in the heterogeneous landscape and intercropped wheat in the homogeneous agricultural landscape.
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