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... Kernel hardness conditioned by puroindoline genes has a profound effect on milling, baking and end-use quality of bread wheat. In this study, 251 current cultivars and advanced lines, 166 historical cultivars, and 219 landraces from China were investigated for their kernel hardness and puroindoline alleles using molecular and biochemical markers. The frequencies of soft, mixed and hard genotypes w ...
Oryza sativa; anthocyanins; varieties; genetic variation; chemical constituents of plants; United States; Japan; China; Philippines; Indonesia; South Korea; North Korea
Triticum; crop yield; environmental factors; varieties; China
Abstract:
... The investigation reported here was carried out at Nanking and Kaifeng which possess greatly different climatic and soil conditions, Many varieties did not show significant disturbance from competition. Some behaved differently in competition in the two places and at different seasons. Only a few varieties showed significant competition throughout the three years at Nanking. However, under abnorma ...
variety trials; planting date; seed germination; boring insects; sowing date; Oryza sativa; early development; direct seeding; crop yield; China
Abstract:
... The earliness of a variety as represented by the date of heading was parallel under the two methods of planting. There was a tendency for some varieties to head earlier when transplanted than when direct planted. The yield results were more complicated. In the rice belt where the conditions were favorable, the yield comparison of varieties by the two methods agreed closely, especially when the two ...
Gossypium; field experimentation; seasonal variation; China
Abstract:
... 1. Increase in size of plat was accompanied by reduction in experimental error, but larger plats were lower in efficiency than the smaller plats. This indicated that increase in number of replications was much more efficient than increasing the size of plat. 2. The shape of the plat was determined by the direction of soil variation. The increase in size of plat in the direction of least associatio ...
Oryza sativa; variety trials; analysis of variance; China
Abstract:
... Three uniformity trials conducted in two rice regions with different environmental conditions in the Chekiang Province, China, were carried out in this study. A different variety was used in each of the three trials. The analysis of variance was used to determine both the most desirable size and shape of plats and the efficiency of randomized distribution of replicated plats. The standard error me ...
height; plant characteristics; Sorghum bicolor; variety trials; Ostrinia nubilalis; Diatraea; plant pests; pest resistance; strains; color; stems; grains; China
Abstract:
... 1. Grain sorghum is attacked by several species of stem borers, such as Pyrausta nubilalis, Diatraea, etc. 2. Data were obtained from the study of infestation in 1,073 strains and varieties in 1933, indicating that the extent of infestation by stem borers varied with varieties, 3. Further data obtained in 1934 under both field and controlled conditions gave further indication of differences in var ...
Brassica rapa subsp. oleifera; Brassica napus var. napus; self-pollination; analysis of variance; inflorescences; inbreeding; open pollination; China
Abstract:
... The paper bag method of selfing has been used to secure inbred seed of rape. The average percentage of seed set was 21.46 in the self- and 63.03 in the open-pollinated inflorescences in the studies conducted in 1934. The average percentage of seed set in 1935 was 23.74 in the self- and 71.47 in the open-pollinated inflorescences. Self pollination results in a decrease in yield of the subsequent pr ...
... In the varietal crosses of rice the mean fertility of F1 of the crosses between Indica and Japonica types of rice is 9.34% and within types 77.40%. Although a significant morphological and genetic difference was found to exist between Indica and Japonica types of rice, the morphological determination did not always coincide with the fertility of F1. Thus it can be concluded that in varietal crosse ...
wind erosion; erosion control; shelterbelts; sandy soils; agricultural land; China
Abstract:
... In some regions of North China shelterbelts have been used for many generations to protect very sandy land from erosion by wind. The method consists of growing trees or bushes in single rows 20 to 60 feet apart in one direction and 100 to 500 feet or more apart at right angles to this general direction. The whole landscape is thus divided into small rectangular fields protected by shelterbelts on ...
... Eighteen soil samples from China, representing Great Soil Groups of varying degree of weathering from Desert Soils to a Latosol were analyzed by fractionation at 5, 2, 0.2, and 0.08 µ, and application of X-ray diffraction and elemental analysis procedures. In the weighted mean of these fractions of Pedocals, illite constituted 35%; of Pedalfers, vermiculite (5–12%) and kaolinite (11–50%) were more ...
... Studies were made of several clays of soils and other deposits to clarify the nature of weathering of layer silicates. Data obtained by X-ray diffraction, thermal, R(OH)n sorption, and elemental analyses lead to the proposal of general occurrence of interstratified X-amorphous zones in 2:1 layer silicates. As weathering of true micas proceeds through illite, intermediates, vermiculite, and montmor ...
... Taxonomic notes are given for a number of rare or poorly known insectivores and bats from Upper Burma and the adjoining frontier regions of Tibet and Assam. Wherever possible, their taxonomic status has been evaluated and their current classification revised. SUMMARY: Taxonomic studies are made of a number of rare or poorly known insectivores and bats from Upper Burma and the adjoining frontier re ...
agricultural policy; exports; international trade; markets; sales; wheat; Canada; China; USSR; United States
Abstract:
... This article attempts to delineate the nature and extent of harmful effects reportedly suffered by Canada as a result of U.S. Public Law 480 wheat exports. Wheat trade data suggest that U.S. P. L. 480 wheat exports depressed total Canadian exports during the fiscal 1955–60 period. Sales to countries such as Communist China and the Soviet Union have improved Canada's overall wheat trade picture sin ...
fertilizer application; grain consumption; grain yield; imports; industry; mineral fertilizers; per capita food consumption; population growth; raw materials; China
Abstract:
... This article discusses the growth of the chemical‐fertilizer industry in Communist China and attempts to make a tentative estimate of the amount of grain China may produce as a result of intensive fertilizer application. Statistical data on production, imports, and consumption are examined and compared with other countries to evaluate the rapidity of growth, the degree of dependency on foreign sup ...
Eremochloa ophiuroides; embryo sac; flowering; megasporogenesis; meiosis; metaphase; microsporocytes; open pollination; pollen; reproductive behavior; sexual development; turf grasses; China; Southeastern United States
Abstract:
... Centipedegrass, Eremochloa ophiuroides (Munro) Hack., is an excellent lawn grass in the southeastern U.S. but information is limited on its cytology, reproductive characteristics, and fertility. Cytological observations on several introductions from China and on local sources of common centipedegrass showed that metaphase I meiosis was regular with nine bivalents; however, eight bivalents + two un ...
Bradyrhizobium japonicum; Glycine max; Japan; Rhizobium; ecotypes; genes; nodulation; serotypes; soybeans; symbiosis; China; South East Asia
Abstract:
... A sample of soybean [Glycine max (L.) Merr.] plant introductions from Asia, representing maturity groups 00 through X, was tested for the presence of the Rj₂ and Rj₄ genes. Both of these genes condition ineffective nodulation responses: Rj₂, specifically with the cl and 122 serogroups of Rhizobium japonicum; Rj₄, with R. japonicum strain 61. Rj₂ was present in 19 of the 851 fines tested. The 19 li ...
case studies; land reform; peasantry; politics; risk; violence; China
Abstract:
... : Peasants have frequently been observed to exhibit two patterns of political behavior which tend to inhibit the formation and consolidation of peasant economic and political organizations, namely political passivity and violence. Theories so far have usually concentrated on explaining either only one of these behavior patterns, or only one class context (either inter‐or intra‐class relations). No ...
... A time-dependent dispersion model based on Lagrangian correlation and calibrated using laboratory data is applied to predict dispersion in four narrow streams in Hong Kong. For early stages of dispersion, the model parameters were completely known from laboratory results. For large times, the Lagrangian time scale t0 for dispersion was estimated by a trial and error procedure. Satisfactory predict ...
decentralization; economic performance; employment; farm management; farms; livestock; prices; sisal; soybeans; wages and remuneration; China
Abstract:
... Chinese economic reforms initiated in 1978 have changed certain management procedures in the state farm sector. Prior to these reforms, state farm management had little control over use of funds, production decisions, and wage setting. After the reforms, financial responsibility was instituted and new wage‐setting devices were implemented which feature closer linking of remuneration to state farm ...
... The study presented herein forms part of a wider research project on dispersion prediction in open channel flows which include laboratory, field and numerical investigations. In this paper, a numerical model which uses finite elements in space and finite differences in time for the solution of the convective-dispersion equation is developed and verified. In the model, the dispersion coefficient is ...
... A previously undescribed virus, for which the name rubus Chinese seed‐borne virus (RCSV) is proposed, was isolated from a single, symptomless plant of an unidentified Rubus species grown from seed collected in the wild in the People's Republic of China, Experimentally RCSV infected 23 out of 39 spp. in six out of eight families. The virus was seed‐transmitted in Chenopodium quinoa (100%) and Nicot ...
Landsat; Tilletia controversa; Tilletia laevis; Tilletia tritici; Triticum; agricultural land; climatic factors; coasts; fungi; ice; pathogens; quarantine; scanners; smut diseases; snow; snowpack; spores; winter wheat; China; Western United States
Abstract:
... Common bunts of wheat (Triticum species) caused by Tilletia caries (DC.) Tul. and T. foetida (Wall.) Liro are present in China, but dwarf bunt has not been reported. Beginning in 1974, wheat shipments from U.S. Pacific Coast states to the People's Republic of China were stopped because they contained spores of the dwarf bunt fungus (Tilletia controversa Kuhn), a pathogen affecting winter wheat. Th ...
plateaus; meadows; plant communities; correspondence analysis; regression analysis; soil; environmental factors; data analysis; steppes; China
Abstract:
... Ngari is the driest, coldest, and highest region on the Tibetan Plateau. During the 1976 Interdisciplinary Scientific Expedition of the Chinese Academy of Sciences to the Qinghai—Xizang (Tibetan) Plateau there was a rare opportunity to study this area. Sampling of 163 sites was done, recording abundances of 241 vascular plant species, along with basic environmental information. The purpose of this ...
Oleaceae; shrubs; surveys; tracheids; trees; wood anatomy; China
Abstract:
... The wood anatomy of 34 species belonging to nine genera of Oleaceae, native or commonly cultivated in China, is described in detail, and a key to the identification of the genera is given. The diversity in wood structure supports the grouping of genera as based on a worldwide wood anatomical survey of the family by Esser and Van der Westen (1983) and Esser et al. (in preparation). Characters to se ...
carcinogenesis; etiology; Vernicia fordii; humans; polycyclic aromatic hydrocarbons; Croton; drugs; carcinoma; Thymelaeaceae; raw materials; risk factors; viruses; esters; pharmacokinetics; carcinogenicity; Human gammaherpesvirus 4; China
Abstract:
... Tumour promoters of the irritant diterpene ester type as risk factors of cancer in man. It is widely accepted in experimental and epidemiologic oncology that in real human life multifactorial causation of cancer is the rule and classical unifactorial causation the exception. This current and comprehensive concept of the aetiology of cancer has evolved essentially from in-depth investigations of tu ...