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Spring Wheat (spring + wheat)
Selected AbstractsGLUTEN QUALITY PREDICTION AND CORRELATION STUDIES IN SPRING WHEATSJOURNAL OF FOOD QUALITY, Issue 4 2007IMRAN PASHA ABSTRACT Gluten, "cohesive, viscoelastic, proteinaceous material prepared as a by-product of the starch isolation from wheat flour" and the storage and dough-forming protein of wheat flour, is the key to the unique ability of wheat to suit the production of leavened products. Wet gluten was only affected by wheat varieties, while dry gluten was affected by wheat varieties, crop years and their interaction. The wet and dry gluten ranged 8.0,43.13% and 2.58,14.55%, respectively, and were positively correlated with Zeleny value, sodium dodecyl sulfate sedimentation value and falling number. The gluten content was higher in Pavon, SA 42 and Faisalabad 85, while Zeleny value was higher in GA 02 and C 518, resulting in better gluten quality. Zeleny value was negatively correlated with crude protein content (r = ,0.1857*). The lowest amount of wet and dry gluten was detected in Triticale and durum wheats as compared to common wheats. Zeleny value and sedimentation value may be used as indicators of gluten content and quality while working on wheats. The information thus collected will be valuable for cereal chemists and wheat breeders for improvements in their future breeding programs. PRACTICAL APPLICATIONS This research work will be a breakthrough and helpful for wheat breeders, growers, millers and bakers for their intended uses as every consumer demand specific wheat quality characteristics for their end products. [source] Reproductive Allocation Patterns in Different Density Populations of Spring WheatJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 2 2008Jing Liu Abstract The effects of increased intraspecific competition on size hierarchies (size inequality) and reproductive allocation were investigated in populations of the annual plant, spring wheat (Triticum aestivum). A series of densities (100, 300, 1 000, 3 000 and 10 000 plants/m2) along a gradient of competition intensity were designed in this experiment. The results showed that average shoot biomass decreased with increased density. Reproductive allocation was negatively correlated to Gini coefficient (R2 = 0.927), which suggested that reproductive allocation is inclined to decrease as size inequality increases. These results suggest that both vegetative and reproductive structures were significantly affected by intensive competition. However, results also indicated that there were different relationships between plant size and reproductive allocation pattern in different densities. In the lowest density population, lacking competition (100 plants/m2), individual reproductive allocation was size independent but, in high density populations (300, 1 000, 3 000 and 10 000 plants/m2), where competition occurred, individual reproductive allocation was size dependent: the small proportion of larger individuals were winners in competition and got higher reproductive allocation (lower marginal reproductive allocation; MRA), and the larger proportion of smaller individuals were suppressed and got lower reproductive allocation (higher MRA). In conclusion, our results support the prediction that elevated intraspecific competition would result in higher levels of size inequality and decreased reproductive allocation (with a negative relationship between them). However, deeper analysis indicated that these frequency- and size-dependent reproductive strategies were not evolutionarily stable strategies. [source] Relationship between Carbon Isotope Discrimination and Grain Yield in Spring Wheat Cultivated under Different Water RegimesJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 10 2007Xing Xu Abstract In C3 plants, carbon isotope discrimination (,) has been proposed as an indirect selection criterion for grain yield. Reported correlations between , and grain yield however, differ highly according to the analyzed organ or tissue, the stage of sampling, and the environment and water regime. In a first experiment carried out in spring wheat during two consecutive seasons in the dry conditions of northwest Mexico (Ciudad Obregon, Sonora), different water treatments were applied, corresponding to the main water regimes available to spring wheat worldwide, and the relationships between , values of different organs and grain yield were examined. Under terminal (post-anthesis) water stress, grain yield was positively associated with , in grain at maturity and in leaf at anthesis, confirming results previously obtained under Mediterranean environments. Under early (pre-anthesis) water stress and residual moisture stress, the association between grain , and yield was weaker and highly depended on the quantity of water stored in the soil at sowing. No correlation was found between , and grain yield under optimal irrigation. The relationship between , and grain yield was also studied during two consecutive seasons in 20 bread wheat cultivars in the Ningxia region (Northern China), characterized by winter drought (pre-anthesis water stress). Wheat was grown under rainfed conditions in two locations (Guyuan and Pengyang) and under irrigated conditions in another two (Yinchuan and Huinong). In Huinong, the crop was also exposed to salt stress. Highly significant positive associations were found between leaf and grain , and grain yields across the environments. The relationship between , and yield within environments highly depended on the quantity of water stored in the soil at sowing, the quantity and distribution of rainfall during the growth cycle, the presence of salt in the soil, and the occurrence of irrigation before anthesis. These two experiments confirmed the value of , as an indirect selection criterion for yield and a phenotyping tool under post-anthesis water stress (including limited irrigation). [source] Crop planting dates: an analysis of global patternsGLOBAL ECOLOGY, Issue 5 2010William J. Sacks ABSTRACT Aim, To assemble a data set of global crop planting and harvesting dates for 19 major crops, explore spatial relationships between planting date and climate for two of them, and compare our analysis with a review of the literature on factors that drive decisions on planting dates. Location, Global. Methods, We digitized and georeferenced existing data on crop planting and harvesting dates from six sources. We then examined relationships between planting dates and temperature, precipitation and potential evapotranspiration using 30-year average climatologies from the Climatic Research Unit, University of East Anglia (CRU CL 2.0). Results, We present global planting date patterns for maize, spring wheat and winter wheat (our full, publicly available data set contains planting and harvesting dates for 19 major crops). Maize planting in the northern mid-latitudes generally occurs in April and May. Daily average air temperatures are usually c. 12,17 °C at the time of maize planting in these regions, although soil moisture often determines planting date more directly than does temperature. Maize planting dates vary more widely in tropical regions. Spring wheat is usually planted at cooler temperatures than maize, between c. 8 and 14 °C in temperate regions. Winter wheat is generally planted in September and October in the northern mid-latitudes. Main conclusions, In temperate regions, spatial patterns of maize and spring wheat planting dates can be predicted reasonably well by assuming a fixed temperature at planting. However, planting dates in lower latitudes and planting dates of winter wheat are more difficult to predict from climate alone. In part this is because planting dates may be chosen to ensure a favourable climate during a critical growth stage, such as flowering, rather than to ensure an optimal climate early in the crop's growth. The lack of predictability is also due to the pervasive influence of technological and socio-economic factors on planting dates. [source] Cropping patterns in the Canadian Prairies: thirty years of changeTHE GEOGRAPHICAL JOURNAL, Issue 2 2002William J. Carlyle Changes in cropping patterns in the Canadian Prairies are examined from the early 1960s to the mid-1990s using census data. Patterns of change within the region are mapped by census division using averaged proportions of land in crops occupied by the main crops for three pairs of census years. Spring wheat and oat have undergone the most significant relative declines. Canola increased dramatically from being the sixth-ranked crop by area in the early 1960s to the third-ranked crop by area by the 1990s. The main change in the Brown soil zone has been a large decline in spring wheat and a compensatory gain in durum wheat. Increases in special crops, especially pulse crops, canola and durum wheat have offset a substantial decline in spring wheat in the Dark Brown soil zone. Barley, tame hay and especially canola have increased at the expense of spring wheat, oat and flaxseed in the Black and Gray soil zones. Prices, transportation costs, changing export markets, crop breeding and local processing all have contributed to these changes. [source] Effects of elevated CO2 associated with maize on multiple generations of the cotton bollworm, Helicoverpa armigeraENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2010Jin Yin Abstract Under elevated environmental carbon dioxide (CO2), leaf chewers tend to compensate for decreased leaf nutritional quality with increased consumption; mortality and development times also increase and cause a reduction in the fitness of leaf chewers. However, the effect of elevated CO2 on multiple successive generations of these and other insects is not well understood. Furthermore, information about the direct effects of increased environmental CO2 on developmental time and consumption of herbivores is lacking. In this paper, we tested the hypothesis that cascade effects of elevated CO2 through plants, rather than the direct effects of elevated CO2, are the main factors decreasing the fitness of cotton bollworm, Helicoverpa armigera Hübner (Lepidoptera: Noctuidae). We used two series of experiments to quantify the growth, development, and consumption of H. armigera fed on an artificial diet or C4 plants (maize) grown under two CO2 levels (ambient vs. double ambient). In the first series of experiments, elevated CO2 had no effect on the population abundance or individual consumption for three successive generations of cotton bollworms fed on an artificial diet. In the second series of experiments, elevated CO2 reduced population abundance of cotton bollworm larvae for two successive generations when they were fed maize milky grains. The specific effects were longer larval duration, lower fecundity, and decreased rm of cotton bollworms. Furthermore, elevated CO2 increased individual consumption when cotton bollworm was fed maize milky grains for two successive generations and decreased the population's total consumption in the first generation but increased it in the second generation. The results from this study indicate that: (1) The effects of elevated CO2 on three successive generations of cotton bollworm fed on artificial diet were weak, or even non-existent, and (2) elevated CO2 increased the consumption when cotton bollworm were fed maize. Our study also suggests that the damage inflicted by cotton bollworm on maize (a C4 plant) will be seriously affected by the increases in atmospheric CO2, which is unlike our previous results for spring wheat (a C3 plant). [source] Crop planting dates: an analysis of global patternsGLOBAL ECOLOGY, Issue 5 2010William J. Sacks ABSTRACT Aim, To assemble a data set of global crop planting and harvesting dates for 19 major crops, explore spatial relationships between planting date and climate for two of them, and compare our analysis with a review of the literature on factors that drive decisions on planting dates. Location, Global. Methods, We digitized and georeferenced existing data on crop planting and harvesting dates from six sources. We then examined relationships between planting dates and temperature, precipitation and potential evapotranspiration using 30-year average climatologies from the Climatic Research Unit, University of East Anglia (CRU CL 2.0). Results, We present global planting date patterns for maize, spring wheat and winter wheat (our full, publicly available data set contains planting and harvesting dates for 19 major crops). Maize planting in the northern mid-latitudes generally occurs in April and May. Daily average air temperatures are usually c. 12,17 °C at the time of maize planting in these regions, although soil moisture often determines planting date more directly than does temperature. Maize planting dates vary more widely in tropical regions. Spring wheat is usually planted at cooler temperatures than maize, between c. 8 and 14 °C in temperate regions. Winter wheat is generally planted in September and October in the northern mid-latitudes. Main conclusions, In temperate regions, spatial patterns of maize and spring wheat planting dates can be predicted reasonably well by assuming a fixed temperature at planting. However, planting dates in lower latitudes and planting dates of winter wheat are more difficult to predict from climate alone. In part this is because planting dates may be chosen to ensure a favourable climate during a critical growth stage, such as flowering, rather than to ensure an optimal climate early in the crop's growth. The lack of predictability is also due to the pervasive influence of technological and socio-economic factors on planting dates. [source] Response of multiple generations of cotton bollworm Helicoverpa armigera Hübner, feeding on spring wheat, to elevated CO2JOURNAL OF APPLIED ENTOMOLOGY, Issue 1 2006G. Wu Abstract:, The growth, development and consumption of three successive generations of cotton bollworm, Helicoverpa armigera (Hübner), reared on milky grains of spring wheat grown under elevated CO2 (double-ambient vs. ambient) in open-top chambers (OTCs) were examined. Decreases in protein, total amino acid, water and nitrogen content, and increases in total non-structure carbohydrates (TNCs) and ratio of TNC : nitrogen were found in wheat milky grains grown under elevated CO2 conditions. Changes in quality of wheat grains affected the growth, development and food utilization of H. armigera. Significantly longer larval lifespan for the third generation and lower pupal weight for all generations were observed in cotton bollworm fed on milky grains of spring wheat grown under elevated CO2 conditions. Bollworm fecundity was significantly decreased for the second and third generations under elevated CO2 levels. The consumption, frass per larva and relative consumption rate significantly increased in elevated CO2 compared with ambient CO2 conditions. However, the potential population consumption was significant reduced by elevated CO2 in the second and third generations. The results of this study indicate that elevated CO2 levels adversely affect grain quality, resulting in consistently increased consumption per larva for a longer period to produce less fecund bollworm through generations, suggesting that net damage of cotton bollworm on wheat will be less under elevated atmospheric CO2 levels because increased consumption is offset by slower development and reduced fecundity. [source] Reproductive Allocation Patterns in Different Density Populations of Spring WheatJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 2 2008Jing Liu Abstract The effects of increased intraspecific competition on size hierarchies (size inequality) and reproductive allocation were investigated in populations of the annual plant, spring wheat (Triticum aestivum). A series of densities (100, 300, 1 000, 3 000 and 10 000 plants/m2) along a gradient of competition intensity were designed in this experiment. The results showed that average shoot biomass decreased with increased density. Reproductive allocation was negatively correlated to Gini coefficient (R2 = 0.927), which suggested that reproductive allocation is inclined to decrease as size inequality increases. These results suggest that both vegetative and reproductive structures were significantly affected by intensive competition. However, results also indicated that there were different relationships between plant size and reproductive allocation pattern in different densities. In the lowest density population, lacking competition (100 plants/m2), individual reproductive allocation was size independent but, in high density populations (300, 1 000, 3 000 and 10 000 plants/m2), where competition occurred, individual reproductive allocation was size dependent: the small proportion of larger individuals were winners in competition and got higher reproductive allocation (lower marginal reproductive allocation; MRA), and the larger proportion of smaller individuals were suppressed and got lower reproductive allocation (higher MRA). In conclusion, our results support the prediction that elevated intraspecific competition would result in higher levels of size inequality and decreased reproductive allocation (with a negative relationship between them). However, deeper analysis indicated that these frequency- and size-dependent reproductive strategies were not evolutionarily stable strategies. [source] Relationship between Carbon Isotope Discrimination and Grain Yield in Spring Wheat Cultivated under Different Water RegimesJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 10 2007Xing Xu Abstract In C3 plants, carbon isotope discrimination (,) has been proposed as an indirect selection criterion for grain yield. Reported correlations between , and grain yield however, differ highly according to the analyzed organ or tissue, the stage of sampling, and the environment and water regime. In a first experiment carried out in spring wheat during two consecutive seasons in the dry conditions of northwest Mexico (Ciudad Obregon, Sonora), different water treatments were applied, corresponding to the main water regimes available to spring wheat worldwide, and the relationships between , values of different organs and grain yield were examined. Under terminal (post-anthesis) water stress, grain yield was positively associated with , in grain at maturity and in leaf at anthesis, confirming results previously obtained under Mediterranean environments. Under early (pre-anthesis) water stress and residual moisture stress, the association between grain , and yield was weaker and highly depended on the quantity of water stored in the soil at sowing. No correlation was found between , and grain yield under optimal irrigation. The relationship between , and grain yield was also studied during two consecutive seasons in 20 bread wheat cultivars in the Ningxia region (Northern China), characterized by winter drought (pre-anthesis water stress). Wheat was grown under rainfed conditions in two locations (Guyuan and Pengyang) and under irrigated conditions in another two (Yinchuan and Huinong). In Huinong, the crop was also exposed to salt stress. Highly significant positive associations were found between leaf and grain , and grain yields across the environments. The relationship between , and yield within environments highly depended on the quantity of water stored in the soil at sowing, the quantity and distribution of rainfall during the growth cycle, the presence of salt in the soil, and the occurrence of irrigation before anthesis. These two experiments confirmed the value of , as an indirect selection criterion for yield and a phenotyping tool under post-anthesis water stress (including limited irrigation). [source] Comparative evaluation of exotic and adapted germplasm of spring wheat for floral characteristics in the Indo-Gangetic Plains of northern IndiaPLANT BREEDING, Issue 6 2007S. K. Singh Abstract Four hundred spring wheat genotypes, comprising exotic and indigenous germplasm and adapted cultivars for commercial cultivation, were investigated during four crop seasons for six floral characteristics related to outcrossing behaviour. Genetic variability and heritability were investigated along with phenotypic correlation coefficients among these characteristics. A significant quantitative variation existed among the characteristics in all three groups. High heritability for stigma length, openness of florets, anther extrusion and duration of floral opening indicated that selection for these characteristics may be effective. The adapted cultivars were found more promising than the exotic and indigenous germplasm. Most of the characteristics showed significantly positive correlation with each other and high correlation was observed between anther and stigma length, and anther extrusion and duration of floral opening. Superiority of varietal mixtures and segregating generations (F3 and F4) of two crosses over parental lines suggested that heterozygosity and heterogeneity can provide yield advantages. Germplasm lines possessing superior expression of floral characteristics may be used to improve yielding ability through enhanced heterozygosity or the development of hybrids. [source] A reciprocal backcross monosomic analysis of the scab resistant spring wheat (Triticum aestivum L.) cultivar, ,Frontana'PLANT BREEDING, Issue 3 2007W. A. Berzonsky Abstract Fusarium head blight (FHB) reduces grain yield of spring wheat and results in deoxynivalenol (DON) production. The resistant spring wheat ,Frontana' could be used to diversify and pyramid resistance. A backcross reciprocal monosomic analysis was conducted to identify ,Frontana' chromosomes with resistance. Disomic lines, one set containing critical chromosomes from ,Frontana' and the other containing chromosomes from susceptible ,Chris', were spray-inoculated and evaluated in separate greenhouse studies (GH-1 and GH-2). Measurements were disease severity at 7 and 14 days, visually diseased kernels, kernels/g and DON content. In GH-2, reciprocal chromosome lines 5B for visually diseased kernels, lines 7B for kernels/g, and lines 4B and 6A for DON content were significantly different. Lines with ,Frontana' chromosomes 3A, 6A and 4D reduced visually diseased kernels, kernels/g and DON content in both studies, while ,Frontana' chromosomes 2A, 2B, 4B and 7B increased susceptibility, as indicated by an increase in these same measurements in both studies. Genes carried on ,Frontana' chromosomes 3A, 6A and 4D could be useful for diversifying and pyramiding sources of FHB resistance. [source] Quality effect of wheat-rye (1R) translocation in ,Pavon 76'PLANT BREEDING, Issue 4 2005W. Kim Abstract A growing interest exists in using wheat for producing both hard and soft wheat products. It would be desirable if 1RS translocations in hard wheat could produce flour suitable for soft wheat products. The objective of this study was to test the effects of centric translocations of chromosome 1 from different rye sources for end-use quality. The quality influences of the 1RS and 1RL translocations and 1R substitutions from different rye sources were studied in a set of hard spring wheat ,Pavon 76'(CIMMYT) lines in three environments in Georgia. The protein concentration of the 1RL translocations was the highest while the 1RS translocations showed no difference in protein concentration compared with that of controls. The 1RS translocations increased alkaline water retention capacity while the 1RL translocations reduced it. T1DSAE1RL was preferred for soft wheat products over other genotypes. [source] Inheritance of resistance to wheat midge, Sitodiplosis mosellana, in spring wheatPLANT BREEDING, Issue 5 2002R. I. H. McKenzie Abstract Inheritance of resistance to a wheat midge, Sitodiplosis mosellana (Géhin), was investigated in spring wheats derived from nine resistant winter wheat cultivars. F1 hybrids were obtained from crosses between resistant winter wheats and susceptible spring wheats, and used to generate doubled haploid populations. These populations segregated in a ratio of 1:1 resistant to susceptible, indicating that a single gene confers the resistance. The F2 progeny from an intercross among spring wheats derived from the nine resistance sources did not segregate for resistance. Therefore, the same gene confers resistance in all nine sources of resistance, although other genes probably affect expression because the level of resistance varied among lines. Heterozygous plants from five crosses between diverse susceptible and resistant spring wheat parents all showed intermediate levels of response, indicating that resistance is partly dominant. Susceptible plants were reliably discriminated from heterozygous or homozygous resistant ones in laboratory tests, based on the survival and development of wheat midge larvae on one or two spikes. This powerful resistance gene, designated Sm1, is simply inherited and can be incorporated readily into breeding programmes for spring or winter wheat. However, the use of this gene by itself may lead to the evolution of a virulent population, once a resistant cultivar is widely grown. [source] Cropping patterns in the Canadian Prairies: thirty years of changeTHE GEOGRAPHICAL JOURNAL, Issue 2 2002William J. Carlyle Changes in cropping patterns in the Canadian Prairies are examined from the early 1960s to the mid-1990s using census data. Patterns of change within the region are mapped by census division using averaged proportions of land in crops occupied by the main crops for three pairs of census years. Spring wheat and oat have undergone the most significant relative declines. Canola increased dramatically from being the sixth-ranked crop by area in the early 1960s to the third-ranked crop by area by the 1990s. The main change in the Brown soil zone has been a large decline in spring wheat and a compensatory gain in durum wheat. Increases in special crops, especially pulse crops, canola and durum wheat have offset a substantial decline in spring wheat in the Dark Brown soil zone. Barley, tame hay and especially canola have increased at the expense of spring wheat, oat and flaxseed in the Black and Gray soil zones. Prices, transportation costs, changing export markets, crop breeding and local processing all have contributed to these changes. [source] Phytate and mineral content in different milling fractions of some Pakistani spring wheatsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 1 2002Faqir M. Anjum Six Pakistani wheat cultivars, namely C-273, Inqulab-91, Pasban-90, Parwaz-94, Shahkar-95 and Rohtas-90, were included in the present study. The kernel weight of the wheat cultivars varied from 31.43 to 36.76 g (per thousand kernels), Parwaz-94 having the highest and Rohtas-90 having the lowest. The test weight of cultivars ranged from 70.23 (Shakar-95) to 76.13 kg hL,1 (Pasban-90). The bran contained the highest amount of phytic acid (6.12%) in C-273 followed by whole-wheat flour (2.23%) in Inqulab-91, and straight-grade flour (0.24%) in Parwaz-94. The phytate content was reduced during the baking of bread and chapati. The bread scores and other quality characteristics varied significantly among cultivars. The total bread scores ranged from 35.20 to 42.00, out of a possible fifty, with Parwaz-94 being the highest. The concentration of minerals varied widely in different milling fractions of various wheat cultivars. The concentration of Cu, Fe, Mn and Zn ranged from 5.00 to 52.50, 26 to 147.50, 0.00 to 97.00, 9.0 to 80.80 ppm, respectively, in different milling fractions of the wheat cultivars. The total chapati scores ranged from 22.40 to 24.20 of a possible score of 30. The minimum chapati scores were found in Rohtas-90 and Parwaz-94, while Inqulab-91 produced the maximum score. [source] Inheritance of resistance to wheat midge, Sitodiplosis mosellana, in spring wheatPLANT BREEDING, Issue 5 2002R. I. H. McKenzie Abstract Inheritance of resistance to a wheat midge, Sitodiplosis mosellana (Géhin), was investigated in spring wheats derived from nine resistant winter wheat cultivars. F1 hybrids were obtained from crosses between resistant winter wheats and susceptible spring wheats, and used to generate doubled haploid populations. These populations segregated in a ratio of 1:1 resistant to susceptible, indicating that a single gene confers the resistance. The F2 progeny from an intercross among spring wheats derived from the nine resistance sources did not segregate for resistance. Therefore, the same gene confers resistance in all nine sources of resistance, although other genes probably affect expression because the level of resistance varied among lines. Heterozygous plants from five crosses between diverse susceptible and resistant spring wheat parents all showed intermediate levels of response, indicating that resistance is partly dominant. Susceptible plants were reliably discriminated from heterozygous or homozygous resistant ones in laboratory tests, based on the survival and development of wheat midge larvae on one or two spikes. This powerful resistance gene, designated Sm1, is simply inherited and can be incorporated readily into breeding programmes for spring or winter wheat. However, the use of this gene by itself may lead to the evolution of a virulent population, once a resistant cultivar is widely grown. [source] | |||||||||||||