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131.
Inja Naga Bheema Lingeswar Reddy Suk-Young Lee Yong-Jin Park Taek-Ryoun Kwon 《Journal of Crop Science and Biotechnology》2017,20(2):137-152
Salinity is one of the major abiotic stresses that severely effects rice production throughout the world. Previously, there have not been many studies which focused on studying diversity among rice germplasm based on specific physiological traits for salt tolerance. Our diversity study was based on physiological traits such as Na+ concentration, K+ concentration, K+/Na+ ratio, osmotic potential, and biomass which are major components determining salt tolerance. This study has systematically analyzed phenotypic data of 191 germplasms in two different salt concentrations apart from the control. The current study identified salt tolerant germplasms based on their response to a single physiological trait as well as a combination of different physiological traits. Some of the germplasm identified outperformed known salt tolerant cultivar Pokkali. This study identifies correlation among various physiological traits. The salt tolerant germplasms can be taken forward into developing better varieties by conventional breeding and exploring genes for salt tolerance. 相似文献
132.
Han-Yong Kim Jonghan Ko Seungtaek Jeong Jun-Hwan Kim Byunwoo Lee 《Journal of Crop Science and Biotechnology》2017,20(5):417-427
Determining effective measures to alleviate the impact of climate change on crops under various regional environments is one of the most urgent issues facing agriculture. In this study, geographic regions of South Korea for future-adjusted barley cultivation were outlined and the impact of climate change on barley production in the next 100 years was evaluated under two greenhouse gas concentration trajectory scenarios: the representative concentration pathway (RCP) 4.5 and RCP 8.5. To achieve our intended study goals, a geospatial crop simulation modeling (GCSM) scheme was formulated using CERES-barley model of Decision Support System for Agricultural Technology (DSSAT) crop model package version 4.6 to simulate grid-based geospatial crop yields. Two experiments were carried out at an open field to obtain model coefficients for the nation and at temperature gradient field chambers to evaluate the performance of the CERES-barley model under elevated temperature conditions. Suitable cultivation regions for three different types of barley (naked, hooded, and malting) under changing climate were projected to expand to the northern regions under both RCP 8.5 and RCP 4.5. However, they were projected to expand more rapidly under RCP 8.5 than those under RCP 4.5. Projected yields of four barley varieties were increased with a slow phase as year progressed under RCP 4.5 scenario. However, they were rapidly increased under RCP 8.5 scenario. It appears that geospatial variation in barley yield under changing climate can be effectively outlined. Therefore, GCSM system might be useful for determining impacts of climate change on geospatial variations of crops, potentially providing means to impede food insecurity. 相似文献
133.
Daniel Hailegiorgis Chong Ae Lee Song Joong Yun 《Journal of Crop Science and Biotechnology》2017,20(5):387-392
Gluten protein determines the processing quality of both durum wheat and bread wheat. The glutenin subunits compositions and associated quality traits of 20 Ethiopian durum wheat varieties were systematically analyzed using SDS-PAGE and Payne numbers. A total of 16 glutenin patterns were identified. At the Glu-A1 locus, all varieties scored the null allele. The predominant glutenin alleles at the Glu-B1 locus were Glu-B1b (7+8) and Glu-B1e (20). In Glu-3, the most abundant glutenin subunits were Glu-A3a and Glu-B3c. Based on the Payne scores, the varieties Yerer, Ginchi, Candate, and Foka were identified to have allelic composition suitable for pasta making. The cluster analysis using agglomerative hierarchical clustering (AHC) method classified the varieties into four similarity classes. Based on the findings of this experiment, suggestions were made for allelic composition improvement through introgression of superior alleles from known Glu-1 and Glu-3 sources. 相似文献
134.
Linu Kuruvilla MB Mohamed Sathik Molly Thomas Lisha.P Luke Sumesh KV 《Journal of Crop Science and Biotechnology》2017,20(5):369-377
Cold stress is one of the major abiotic factors that influence the productivity and geographical distribution of many agriculturally important crops like Hevea brasiliensis. Cultivation of H. brasiliensis in India is being extended to northeastern regions, where low temperature during winter adversely affects its survival, growth, and productivity. Developing cold-tolerant genotypes is a primary requisite to maximize the productivity under such challenging environmental conditions. However, lack of methods for early evaluation of cold tolerance in the newly developed clones and the extensive time required for assessing their tolerance in the field are major constraints for clonal selection. The present study was initiated with an objective to identify and characterize cold stress responsive miRNAs from H. brasiliensis that show stronger association with cold tolerance. Next generation sequencing using Illumina HiSeq method revealed the expression of 21 and 29 conserved miRNA (from clone RRIM 600) families in cold-stressed and control samples, respectively. Forty-two novel miRNAs were identified from this study. Upon differential expression analysis, eight conserved miRNAs were found commonly expressed in both the samples. When expression analyses were performed subsequently with six selected miRNAs in two Hevea clones (viz. RRII 105 and RRIM 600), miR169 showed a strong association with cold tolerance. miRNAs such as miR482 and miR159 also exhibited association with cold tolerance. This study suggests the possibility of employing these miRNAs as markers for cold tolerance after validation in more number of genotypes with varying levels of cold tolerance. 相似文献
135.
This research was conducted to determine the changes in the seasonal carbohydrates of annual shoots and growth characteristics of 10 years old ‘Trakya ?lkeren’ grape variety. Grapevines are grafted on 5BB and 5C rootstocks and they were grown in heavy clay soil conditions. In the study, changes of sugar, starch and total carbohydrates were determined from bud burst to dormancy. While sugar, starch and total carbohydrates showed significant differences (P < 0.01) there were no differences between rootstocks. Although sugar, starch and total carbohydrates of shoots decreased from bud burst to blooming, they increased thereafter until vegetative growth stopped. Total carbohydrates of annual shoots have been found to accumulate in period from blooming to harvest. Total and mean leaf area, shoot length and diameter, total chlorophyll and chlorophyll a/b ratio showed significantly variation among rootstocks and phenological stages (P < 0.01). Whereas the highest chlorophyll contents were found in the blooming, it was found at the lowest through to harvest. Overall mean and total leaf area, shoot length and shoot diameter, total chlorophyll content and chlorophyll a/b ratio were significantly higher on 5BB grafted vines. In the study, 5BB rootstocks are found suitable in terms of shoot carbohydrate accumulation and growth characteristics for ‘Trakya ?lkeren’ grape variety. 相似文献
136.
This study was carried out in ?scehisar district of Afyonkarahisar on ‘0900-Ziraat’ sweet cherry cultivar for two successive years in 2011 and 2012. Ten different applications consisting of 80?g FeSO4.7H2O tree?1, 20?g FeEDDHA tree?1, 420?mL TK?-Hümas tree?1, 80?g FeSO4.7H2O + 420?mL TK?-Hümas tree?1, 200?g powder sulphur (S) tree?1, 80?g FeSO4.7H2O + 200?g powder S tree?1, 25?g ZnSO4.7H2O tree?1, 25?g ZnSO4.7H2O + 420?mL TK?-Hümas tree?1 and 25?g ZnSO4.7H2O + 200?g powder S tree?1 were subjected for determination of their effect on vegetative growth of sweet cherry. In this study, shoot diameter, shoot length, leaf total chlorophyll content, leaf area and leaf iron (Fe) and zinc (Zn) contents were obtained. Shoot length, shoot diameter and leaf area showed general increases in 80?g FeSO4.7H2O + 200?g powder S tree?1 and 25?g ZnSO4.7H2O + 200?g powder S tree?1 treatments.The results clearly indicated that he treatments had different effects on the shoot length and shoot diameter although there was a differences between the experimental years. Particularly, significantly positive effects of the treatments on leaf total chlorophyll was apparent for the second year’s observations. In addition, Fe and Zn concentrations in leaf were markedly increased in response to the treatments. 相似文献
137.
David M. Cole Timothy L. White P. K. R. Nair 《Genetic Resources and Crop Evolution》2007,54(1):189-204
Knowledge of the effects of farmer practices on population genetic parameters of peach palm (Bactris gasipaes Kunth) is relevant to the improvement and conservation of the palm’s genetic resources. Microsatellite markers were used
to assess genetic diversity and population structure of peach palm in swidden-fallow agroforestry systems in northeastern
Peru. The study covered eight communities, comprising two study areas 160 km apart – one occupied by indigenous Amerindians
and the other by mixed race campesinos. Simultaneous analysis of an ex situ peach palm germplasm collection provided a means to compare population genetic parameters. Farmers who were surveyed on seed
selection practices for peach palm reported that an average of only four palms (4.3 for campesino and 1.5 for indigenous populations)
were used to provide seed for the establishment of the forest gardens sampled. As expected, inbreeding coefficients observed
within communities were relatively high (f = 0.105 − 0.210), however, observed heterozygosities within communities were also high (0.625–0.741). A metapopulation approach
was used to describe migration within and among regions, implying a hierarchical structure of gene flow which maintains relatively
high levels of genetic diversity. Seed migration was found to occur over longer distances (≤600 km) and at a higher frequency
(46% of palms sampled) in the indigenous study area, and a proportionally greater number of alleles was found (49 vs. 43 over
three loci) with twice as many private alleles occurring only in the indigenous populations. The farmers’ practice of preserving
remnant palms through successive swidden generations may have contributed to the maintenance of alleles by reducing the severity
of founder effects. Although the campesino study area exhibited a significant (20% of the variation; p < 0.01) isolation-by-distance relationship across 35 km distance, in general, both study populations had relatively limited
genetic structure (θ = 0.012–0.03), which is believed to have resulted from the exchange of seeds over long distances and
periods of time. 相似文献
138.
Background, Aim and Scope The distribution of sediments in estuarine beaches is controlled by the interactions between sediment supply, hydrodynamic
processes and human intervention. The main purpose of this study is to characterize the sediments of Tagus estuarine beaches
in order to understand their origin and to contribute to a better knowledge of the Tagus estuary sediment budget.
Methods Surface sediment samples were collected across beach profiles and sand grain size analysis was performed by dry sieving. Grain
size statistics for the median (d50) and standard deviation (SDM) were obtained using the Moment method. This study was complemented by a qualitative evaluation
of the sediment composition. Cross-shore topographic surveys were conducted for selected sampling sites.
Results Tagus estuarine beach sediments are mainly composed of quartz sand particles which are fine-grained and well sorted near the
mouth of the estuary and medium to coarse-grained and moderately sorted in the inner domain. Compositional results show evidence
of active anthropogenic sediment sources, especially in the coarser fractions.
Discussion The analysis of the textural and compositional characteristics of beach sediments in the inner estuarine domain is compatible
with local sedimentary sources, while a marine signature is present at the mouth and inlet channel sediments. In the inner
domain, differences in the sedimentary processes are represented by the textural characteristics of the sediments, such as
the sorting degree and the gravel content. Sediment characteristics also reflect human intervention in the system, with the
introduction of anthropogenic and allochthonous particles and the mixture of sediments from different sources.
Conclusions The sediments of the inner Tagus estuarine beaches are derived from local Plio-Pleistocene outcrops while inlet and outer
estuary beaches reveal a dominant marine source. Beach textural variability observed in the inner domain is not related to
wave forcing gradients, but mainly to variations in the sedimentary processes along the estuarine margins and to human intervention.
Results show that the Tagus estuarine beaches depended, almost exclusively, on sediment input from local sources until the
last century. With increasing human occupation, sediment transfers became dominated by anthropogenically related activities
mainly connected with the occupation of estuarine margins and dredging.
Recommendations and Perspectives Further studies should extend the present level of knowledge in what concerns sand transport patterns through additional compositional
and geochemical analysis, and the development of new techniques in order to allow the quantitative evaluation of the impact
of human activities on the sediment budget. 相似文献
139.
Soil enzymes are linked to microbial functions and nutrient cycling in forest ecosystems and are considered sensitive to soil
disturbances. We investigated the effects of severe soil compaction and whole-tree harvesting plus forest floor removal (referred
to as FFR below, compared with stem-only harvesting) on available N, microbial biomass C (MBC), microbial biomass N (MBN),
and microbial biomass P (MBP), and dehydrogenase, protease, and phosphatase activities in the forest floor and 0–10 cm mineral
soil in a boreal aspen (Populus tremuloides Michx.) forest soil near Dawson Creek, British Columbia, Canada. In the forest floor, no soil compaction effects were observed
for any of the soil microbial or enzyme activity parameters measured. In the mineral soil, compaction reduced available N,
MBP, and acid phosphatase by 53, 47, and 48%, respectively, when forest floor was intact, and protease and alkaline phosphatase
activities by 28 and 27%, respectively, regardless of FFR. Forest floor removal reduced available P, MBC, MBN, and protease
and alkaline phosphatase activities by 38, 46, 49, 25, and 45%, respectively, regardless of soil compaction, and available
N, MBP, and acid phosphatase activity by 52, 50, and 39%, respectively, in the noncompacted soil. Neither soil compaction
nor FFR affected dehydrogenase activities. Reductions in microbial biomass and protease and phosphatase activities after compaction
and FFR likely led to the reduced N and P availabilities in the soil. Our results indicate that microbial biomass and enzyme
activities were sensitive to soil compaction and FFR and that such disturbances had negative consequences for forest soil
N and P cycling and fertility. 相似文献
140.
Influence of non-cellulose structural carbohydrate composition on plant material decomposition in soil 总被引:1,自引:0,他引:1
Sophie Gunnarsson Håkan Marstorp A Sigrun Dahlin Ernst Witter 《Biology and Fertility of Soils》2008,45(1):27-36
The C mineralisation pattern during the early stage of decomposition of plant materials is largely determined by their content
of different carbohydrates. This study investigated whether detailed plant analysis could provide a better prediction of C
mineralisation during decomposition than proximate analysis [neutral detergent solution (NDF)/acid detergent solution (ADF)].
The detailed analysis included sugars, fructans, starch, pectin, cellulose, lignin and organic N. To determine whether differences
in decomposition rate were related to differences in hemicellulose composition, the analysis particularly emphasised the concentrations
of arabinose and xylose in hemicelluloses. Carbon dioxide evolution was monitored hourly in soil amended with ten different
plant materials. Principal component and regression analysis showed that C mineralisation during day 1 was closely related
to free sugars, fructans and soluble organic N components (R
2 = 0.83). The sum of non-cellulose structural carbohydrates (intermediate NDF/ADF fraction) was not related to C mineralisation
between days 1 and 9. In contrast, a model including starch and protein in addition to the non-cellulose structural carbohydrates,
with the hemicelluloses replaced by arabinose and xylose, showed a strong relationship with evolved CO2 (R
2 = 0.87). Carbon mineralisation between days 9 and 34 was better explained by xylan, cellulose and lignin (R
2 = 0.72) than by lignocellulose in the ADF fraction. Our results indicated that proximate analyses were not sufficient to
explain differences in decomposition. To predict C mineralisation from the range of plant materials studied, we propose a
minimum set of analyses comprising total N, free sugars, starch, arabinose, xylan, cellulose and lignin. 相似文献