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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

The effects of fertilization and crop rotations on rainfed barley development, growth and yields, in a semi-arid mediterranean-type climate /

Rached, E. M. January 1986 (has links)
A study was conducted for two growing seasons in northeastern Syria to evaluate the effect of N and P fertilizers and previous crops--i.e. vetch (Vicia sativa L.), barley (Hordeum vulgare L. cv. Beecher) or fallow--on water consumption, development, growth and yields of barley in a semi-arid, Mediterranean-type climate. / The two seasons contrasted in rainfall and temperature which affected soil N, water use and yields. Fertilizer addition and residual P were the major determinants in barley yield increases. Rotation effects were significant only when fertilizers were added. Fallowing was an inefficient way of storing water, but stored water was used most efficiently by subsequent barley crops when fertilized. / Fertilizers did not increase total evapotranspiration. Water use efficiency was related to dry matter production at stem elongation (DMse). Grain weight was a stable component of grain yields. Grain number was related to crop growth rates during the three week pre-anthesis period and to DMse, in turn affected by temperature, nutrient and moisture conditions. / Vetch yields were in the order of 2.5 t.ha$ sp{-1}$ in the wetter season (1982/83). / Results showed that substantial barley yield increases can be obtained with innovative crop rotations and appropriate use of fertilizers in semi-arid environments.
12

The apical development, and the effects of chlormequat and ethephon on the development, physiology and yield of spring barley /

Ma, Baoluo January 1991 (has links)
No description available.
13

The effects of fertilization and crop rotations on rainfed barley development, growth and yields, in a semi-arid mediterranean-type climate /

Rached, E. M. January 1986 (has links)
No description available.
14

The effect on yield of cross-breeding varieties of barley

Trimble, Joseph Marshall January 1915 (has links)
The purpose of this experiment is to test the relative yields of grain from across-bred grains s.s compared with self fertilized seed of the same varieties. It was originally purported to make these tests with both wheat and barley. However, owing to unfavorable greenhouse conditions the wheat plants bloomed very poorly and the crosses made set very little seed so the wheat was dropped and the work done entirely with barley. Before entering into the details of the work conducted, a brief review will be made of small grain breeding work at other places. The Agricultural Experiment Station of Wisconsin has only recently issued a bulletin on barley cultivation. Barley being one of the principal crops of Wisconsin, the Experiment Station has made considerable effort to improve the seed production. Individual selection and crossbreeding have been carried on extensively. Up to the present time no cross-bred varieties have been developed that compare favorably with the pure strains. Their great work has been in individual selection and the production of the so-called pedigree barleys. They started by procuring foundation stock from the best varieties in the United States and Canada. These were planted in small plats and watched carefully during their growth. At harvest time the best heads were selected from the best plants. These were in turn grovm in centgener beds and again selected. After five years of this close selection larger quantities of seed were saved and planted. The sixth year small quantities of this seed were sent out to co-operating students all over the state. In this way the new varieties were disseminated throughout the state and were soon available to every farmer in the state. The Wisconsin station bred for large yields, for resistance to smuts, and for uniformity in size and quality of grain, in length and strength of straw and in time of germination and maturity. In twelve years time sixteen different strains of pedigree barley were developed that were superior to the old strains.The six-row bearded was found to be superior to all other varieties. Minnesota has probably done as much or more work than any other State in breeding and improving wheat. The Experiment station has been working for twenty-five years to produce improved strains for the use of Minnesota farmers and have been well repaid in many cases. Their work has been along the usual lines of cross breeding and selection. Two kinds of cross breeding were practiced - out-crosses and in-crosses. Out-crosses were made between plants of different varieties and in-crosses between plants of the same variety. The seed from these crosses was planted and the best one plant from each arose selected to continue the breeding. This individual selection was continued for several years before it was put out as a new variety. In this way several new varieties were developed that yielded very creditably with the best of the old varieties. However, it was found that large numbers had to be worked with in order to get even one cross that was good. The vast majority of them were no good. While out-crosses were harder to get than in-crosses, they gave more evidence of being crossed than did the in-crosses. Only one of the in-crosses showed enough variation from the parent stock to indicate that it was hybrid. Some of the best known varieties originating from crosses are the Fife and Blue stem wheats. After establishing a new variety it was disseminated throughout the state in much the same way as the barley varieties were in Wisconsin. The gain to the farmers of the state by this practice has been immense. It made available for the farmer pedigreed seed that was far superior to the scrub stock commonly used. The Nebraska Experiment station nas done a great deal of wheat breeding work in last twenty years, mainly along lines of selection. In former years the greater part of the wheat grown in Nebraska was spring wheat. The wields were not what they should be so attention was turned to winter wheats. The experiment station took the matter up and has developed a winter wheat that has increased the yield five bushels and more per acre. The variety found to be best suited to Nebraska was the Turkey Red. Dr. T. L. Lyon undertook to improve this variety by a systematic method of selection. To start with he took one thousand select heads and planted them in separate rows in the nursery. The second year the best heads from these rows were planted. This was continued for three years, some of the poorest being discarded each year. At the end of three years. The seed was planted in thirtieth-acre plats. For five years this was continued until good comparisons could be made of the various strains. Then the wheat was sold in ten bushel lots, in different sections of the state on the condition that the buyer should seed according to instructions and make a report on the results. The reports showed that an average of twenty-one tests in twenty counties gave a net increase of four bushels per acre over the local Turkey Red Wheat. In only three instances did the local wheat excel the improved strains. Dr. Hjalmar Wilssen of the Swedish Experiment Station, has done a great deal of breeding work with small grains. He has made selections tending toward improvement along all lines. In some instances he has been successful and in others very unsuccessful. He found that deficiencies of technical nature could be overcome, such as length of spikelet but where the foundation principles were concerned it was more difficult and sometimes impossible. One of his failures was an attempt to breed few stronger culms in barley. One of the most valuable barleys grown in Sweden was disposed to lodge or fall down. Nilsson tried to remedy this by selection. He spent years of hard work on the problem but never accomplished anything and finally gave it up. He later accomplished his end problem by producing another strain of barley which had as good quality as the old, and at the same time had strong culms. / Master of Science
15

Characterisation and mapping of chromosome regions associated with improved growth and grain yield of barley on sandy soils of low fertility / by Nigel Richard Long.

Long, Nigel R. January 2003 (has links)
"August, 2003" / Includes bibliographical references (leaves 260-292) / v, 294 leaves : ill. (some col.), plates (col.), maps (col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, School of Agriculture and Wine, 2003
16

Biomass and protein yields, N2-fixation and N transfer in annual forage legume-barley (Hordeum vulgare L.) cropping systems

Sampson, Helen G. (Helen Grace) January 1993 (has links)
In this study, six annual legumes and the perennial, red clover (Trifolium pratense L.) were monocropped (MC) and intercropped (IC) with barley in a field study with three N levels, 0, 30 and 60 kg N ha$ sp{-1}$. At O kg N ha$ sp{-1}$, N$ sb2$-fixation and N transfer were estimated by the $ sp{15}$N isotope dilution (ID) method. At 60 kg N ha$ sp{-1}$, a direct $ sp{15}$N labelling method was employed to study N transfer. The hypotheses were that the annual species would be more productive within one growing season than red clover, that increased N levels would increase herbage dry matter (DM) and crude protein (CP), that the proportion of N derived from N$ sb2$-fixation in IC-legumes would be higher than that of MC-legumes and that within intercrops there would be evidence of N transfer. In neither year was the total DM yield of red clover, MC or IC, less than the rest of the legumes. In 1991, the total DM yield of intercrops responded to 30 kg N ha$ sp{-1}$; in neither year did the estimated total CP yield of MC-legumes or intercrops respond to N levels. Only in 1992 was there evidence of N$ sb2$-fixation and the proportion of N derived from fixation by IC-legumes was 145% higher than that of MC-legumes. Only the $ sp{15}$N direct labelling method gave evidence of N transfer, to associated legume and barley plants in 1991, and to associated legume plants in 1992.
17

Crop response models for intensive cereal management applied to barley and wheat in Québec

Stephen, Bruce G. January 1993 (has links)
This thesis presents an investigation of two production functions (a non-linear-in-parameters and a generalized polynomial) in order to determine which function most appropriately represents the observed relationships of the components of ICM technology. Four spring barley and one spring wheat datasets were assembled from ICM field trials conducted in the Montreal region (1987-89). / A quadratic and a Mitscherlich-Baule equation were fitted to the (five) datasets and compared with respect to a number of measures of goodness of fit. One dataset was chosen for generating and graphing a three-dimensional response surface, based on the fitted equations of that dataset. The two surfaces were compared in light of expectations regarding the two equations. / The fitted equations of three of the five datasets did not produce noteworthy results. The other two datasets provided mixed results. The response surfaces provided outcomes that were contrary to prior expectations. In general graphing the response surfaces offered limited additional insight. Ultimately, this project may have been hampered by the experimental design of the field trials, those designs being oriented to results of agronomic rather than economic significance.
18

Variation in yield and protein content of malting barley : methods to monitor and ways to control /

Pettersson, Carl Göran, January 2006 (has links) (PDF)
Licentiatavhandling (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2006. / Härtill 2 uppsatser.
19

Biomass and protein yields, N2-fixation and N transfer in annual forage legume-barley (Hordeum vulgare L.) cropping systems

Sampson, Helen G. (Helen Grace) January 1993 (has links)
No description available.
20

Crop response models for intensive cereal management applied to barley and wheat in Québec

Stephen, Bruce G. January 1993 (has links)
No description available.

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