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Articles 1711 - 1740 of 58740
Full-Text Articles in Physical Sciences and Mathematics
Forestry, A Valuable Crop For The Pastoral Farmer, N M. Shadbolt
Forestry, A Valuable Crop For The Pastoral Farmer, N M. Shadbolt
IGC Proceedings (1993-2023)
The integration of forestry into a pastoral system (sheep & beef cattle) will be discussed with respect to the economic sustainability of the system. The cash flow implications for a case study farm of forest development, and methods used through forestry right agreements to facilitate these by reducing risk, will be developed.
The Effects Of Tree Density On Pasture Production Under Acacia Melanoxylon, B S. Thorrold, I L. Power, M B. Dodd
The Effects Of Tree Density On Pasture Production Under Acacia Melanoxylon, B S. Thorrold, I L. Power, M B. Dodd
IGC Proceedings (1993-2023)
Silvi-pastoral systems could contribute to greater total productivity and more sustainable land management of grazed pastures in New Zealand. Despite this potential, little is known of the interactions of tree species and environment on pasture growth. In this paper we report the effects of tree density on pasture yield in an Acacia melanoxylon silvi-pastoral system. The results show decreasing pasture yield with increasing tree density, although the extent of the reduction is less than would be expected under Pinus radiata. Results suggest that shade is the dominant factor causing yield decline in this study, while reduced N availability is …
Long-Term Impact Of Leucaena-Based Grazing Systems On Soil Acidity, A D. Noble, R J. Jones
Long-Term Impact Of Leucaena-Based Grazing Systems On Soil Acidity, A D. Noble, R J. Jones
IGC Proceedings (1993-2023)
Soil acidification and land degradation issues are assuming increasing importance in Australia and challenging the concept of sustainablity of current land management systems. In this study the impact of a 22 year old Leucaena leucocephala / Urochloa mosambicensis (Leucaena) pasture production system on soil acidification and selected soil chemical properties was compared to an adjacent Urochloa mosambicensis (Sabi) area. Significant acidification and cation depletion was observed to 70 cm under the Leucaena when compared to the Sabi system. The net acidification rate for the Leucaena system was estimated to be 2.73 kmol H+ ha-1 yr-1 of which 0.17 kmol …
Farmers' Screening Of Indigenous Fodder Trees And Shrubs In Kenya, R L. Roothaert, H K. Arimi, E N. Kamau
Farmers' Screening Of Indigenous Fodder Trees And Shrubs In Kenya, R L. Roothaert, H K. Arimi, E N. Kamau
IGC Proceedings (1993-2023)
The lack of fodder quantity and quality is a constraint for small scale livestock production systems in central Kenya which are intensive or are rapidly becoming so. This study examined farmers’ knowledge about indigenous fodder trees and shrubs (IFTS) which are fed to livestock. The study consisted of a formal survey in three agroecological zones with mean annual rainfall varying from 750 to 1400 mm. Farmers rated IFTS for different qualities, which were analysed by Chi square. Differences of ratings among species for these qualities were significant (p<0.05). The most promising species for the sub-humid zone, in terms of what farmers want to plant and in terms of preliminary nutritive analysis, were: Tithonia diversifolia, Commiphora zimmermanii, Ficus spp. and Trema orientalis. The species …
Scale Of Patchiness Affects The Relation Between Forage Quality And Patch Choice By Cattle, Wallis Devries, M F. Laca, E A. Laca
Scale Of Patchiness Affects The Relation Between Forage Quality And Patch Choice By Cattle, Wallis Devries, M F. Laca, E A. Laca
IGC Proceedings (1993-2023)
We predicted and tested the effects of scale of heterogeneity on movements and selectivity of a large grazer in a controlled field experiment. We created random mosaics of short/high quality and tall/low quality grass patches in equal proportion at grid sizes of 2x2 m and 5x5 m. Subsequently, we monitored the foraging behavior of four steers in 16 20x40 m plots over 30-minute periods. As predicted, the animals selected the short patches both by walking in a nonrandom manner and by concentrating their grazing time. Selectivity was more pronounced in large patches than in small ones. In contrast, the number …
Spatial Analysis Of Land Use By Cattle Herds In A Village Of The Sudanese Zone In Senegal. Application For Grazing System Improvement, A Ickowicz, J C. Usengumuremyi, D Bastien, N De Choudens
Spatial Analysis Of Land Use By Cattle Herds In A Village Of The Sudanese Zone In Senegal. Application For Grazing System Improvement, A Ickowicz, J C. Usengumuremyi, D Bastien, N De Choudens
IGC Proceedings (1993-2023)
Spatial analysis of land use by cattle herds in the sub-humid area of Senegal is conducted through the utilisation of a Geographic Information System. This tool allows us to establish relationships between spatial practices, ruminant nutrition and performances. It gives leads to proposals for the improvement of the extensive ruminant feeding system.
Using Cuticular Wax Alkanes And Computer Simulation To Estimate Diet Selection, Herbage Intake And Nutrient Cycling In Grazing Sheep, H Dove, R J. Simpson
Using Cuticular Wax Alkanes And Computer Simulation To Estimate Diet Selection, Herbage Intake And Nutrient Cycling In Grazing Sheep, H Dove, R J. Simpson
IGC Proceedings (1993-2023)
In grazing ewes, plant cuticular wax alkanes were used as markers to estimate diet selection, herbage intake, N intake and N excretion in faeces. Pasture and animal data were then used as inputs to the decision-support system GrazFeed, which simulates grazing and digestion to predict herbage intake, N intake and N excretion. Estimated and predicted intakes agreed closely, especially for N intake, and it is concluded that, subject to further investigation of the possibility that GrazFeed slightly under-estimated faecal N excretion, the close agreement between estimated and predicted OM and N intakes suggests that this combined use of alkane methods …
Effect Of Species Horizontal Distribution On Defoliation Of Ryegrass-Clover Swards Grazed By Sheep, P C. De Faccio Carvalho, F Louault, M Lafarge
Effect Of Species Horizontal Distribution On Defoliation Of Ryegrass-Clover Swards Grazed By Sheep, P C. De Faccio Carvalho, F Louault, M Lafarge
IGC Proceedings (1993-2023)
Defoliation events on labelled white clover (Trifolium repens) growing points or ryegrass (Lolium perenne) tillers were measured during grazing tests by sheep with swards consisting of mixed ryegrass-clover (MIX) or alternate strips of clover and ryegrass (STRIP). Sward surface height was maintained at 6.4 cm by lawnmower cuts in order to obtain a similar surface height for both species. On average, during 13 grazing tests in STRIP and 11 in MIX swards, clover was the more defoliated species : 23.3% of the growing points in STRIP and 26.5% in MIX swards were defoliated compared to 16.2% …
Foraging Behavior Of Zebu Cattle Grazing Deciduous Forest, L Ortega, J Castillo, F Rivas
Foraging Behavior Of Zebu Cattle Grazing Deciduous Forest, L Ortega, J Castillo, F Rivas
IGC Proceedings (1993-2023)
The objective of this study was to determine whether the foraging behavior of Zebu cattle in deciduous forest was affected by time of the year. Data were recorded during the wet, nortes and dry seasons. Ten Zebu cows were used to record biting rate. Intake and bite size was estimated using three esophageally fistulated animals. Cattle browsed shrubs and trees in the wet season and ingested litter leaves in the dry season which resulted in differences of ingestive behavior. In general, bite size and intake were higher in the wet season and decreased during the nortes and dry seasons.
Behaviour Of Cattle On Two Different Types Of Upland Pastures, D Macesic, M Knezevic
Behaviour Of Cattle On Two Different Types Of Upland Pastures, D Macesic, M Knezevic
IGC Proceedings (1993-2023)
The purpose of this research was to study the influence of the quality of pastures on the behaviour of cows in a 'cow-calf' system. The behaviour was measured by the four principal activities of the herd: grazing, lying, 'roaming' and insect repelling, and it is presented with relative indicators. The trial was conducted on pasture areas of the Faculty of Agriculture, University of Zagreb, at the altitude of 650- 850 m. The influence of the pasture quality on the behaviour of cattle on pasture was studied on two different types of pastures: a natural unreclaimed pasture belonging to the Arrhenatheretum …
Foraging Behaviour Of Heifers, Sheep And Goats In Grass-Legume Cafeteria, J P. Singh, Vinod Shankar, V S. Upadhyay
Foraging Behaviour Of Heifers, Sheep And Goats In Grass-Legume Cafeteria, J P. Singh, Vinod Shankar, V S. Upadhyay
IGC Proceedings (1993-2023)
The paper reports findings of a grazing trial with heifers, sheep and goats in a grass–legume cafeteria involving 45x10 m alternate strips of 18 grasses and 18 legumes. In the first year heifers were grazed. Sheep were introduced in the second year and goats in the third year. The stocking rate was 1.5 ACU/ha. Foraging behaviour of three kinds of animals differed in many respects with grazing and rest durations, choice of species in the forenoon and afternoon and in different seasons. Heifers, by and large, preferred grasses over legumes and browse. Sheep, on the contrary, preferred legumes over grasses …
Effects Of Defoliation Frequency On Foraging Selective Behaviour In Pasture With Paspalum Dilatatum, G L. Acosta, A T. Ayala Torales, V A. Deregibus
Effects Of Defoliation Frequency On Foraging Selective Behaviour In Pasture With Paspalum Dilatatum, G L. Acosta, A T. Ayala Torales, V A. Deregibus
IGC Proceedings (1993-2023)
The objective was to assess defoliation effects exerted by sheep grazing on a pasture composed by falaris and dallisgrass, at two phenological stages during spring and summer. A sown pasture of Phalaris aquatica and Paspalum dilatatum were grazed at two phenological stages: stage I (SI), with no more than 5% of reproductive tillers, and stage II (SII), with at least 70% of reproductive tillers. Tillers of both grass species were marked with plastic colour rings along two transects in each plot. Phenological stage of tillers, and the number, age and length of each leaf per tiller were registered. Tiller defoliation …
Characterization Of Grazing Patterns In Cool-Season Annual And Warm-Season Perennial Grass Pastures, G E. Aiken, M S. West, D I. Bransby
Characterization Of Grazing Patterns In Cool-Season Annual And Warm-Season Perennial Grass Pastures, G E. Aiken, M S. West, D I. Bransby
IGC Proceedings (1993-2023)
Pastures are often either under- or over-grazed, which can affect both pasture sustainability and livestock performance. Disk meter heights were measured for rye (Secale cereale L.) -ryegrass (Lolium L. multiflorum Lam.) pasture to characterize stocking rate (2.5, 3.7, and 4.9 steers/ha) effects on grazing patterns. In another study, grazing indices were calculated for bermudagrass [Cynodon dactylon (L.) Pers.] to describe pasture utilization over time for three stocking rates (3.0, 5.9, 8.9 steers/ha). Distributions of DMH for rye-ryegrass showed distinct grazing patterns for each stocking rate, with the distributions changing from bimodal to multi-modal from heavy to light …
Border Effects On Cattle Grazing Preference, G E. Shewmaker, H F. Mayland, S B. Hansen
Border Effects On Cattle Grazing Preference, G E. Shewmaker, H F. Mayland, S B. Hansen
IGC Proceedings (1993-2023)
The objective was to examine the effect of row position on cattle grazing preference. Grazing preference of eight tall fescues [Festuca arundinacea (Schreb.)] was evaluated by ocular preference scores at 30 hr (PS30) and 48 hr (PS48). Six rows of a cultivar—numbered consecutively within each plot from left to right—formed one plot. Rows 1&6 were on the outside edges of the plot and rows 3&4 were in the middle. Within a replication, rows 1 and 6 were adjacent to rows 6 and 1 of adjacent plots, respectively. During the first year, row position was not a significant effect. However, …
Intake And Diet Selection By Sheep Grazing Grass/Clover Patches, I J. Gordon, A W. Illius
Intake And Diet Selection By Sheep Grazing Grass/Clover Patches, I J. Gordon, A W. Illius
IGC Proceedings (1993-2023)
The effects of the spatial dispersion of ryegrass (Lolium perenne L) and clover (Trifolium repens L), at the feeding station scale, on diet composition and feeding behaviour were studied for sheep. There were no significant changes in diet composition with changes in the spatial dispersion of sward components. Bite size, bite rate and intake rate did increase as the species became more aggregated.
Relationships Between The Nutrient Content Of Irrigated Pasture On Offer And That Selected By Grazing Dairy Cows, W J. Wales, C R. Stockdale, P T. Doyle
Relationships Between The Nutrient Content Of Irrigated Pasture On Offer And That Selected By Grazing Dairy Cows, W J. Wales, C R. Stockdale, P T. Doyle
IGC Proceedings (1993-2023)
An experiment was conducted to determine the dry matter, energy, crude protein and fibre intake by dairy cows in late lactation when grazing perennial pasture offered at allocations of 15, 20, 30 and 40 kg DM/cow.day. The cows consistently selected a diet 10% higher in digestibility than that on offer. In contrast, cows selected diets with crude protein levels increasing from 22% to 40%, above that in pasture on offer, as pasture allocation increased. A similar pattern was observed for the intake of white clover (Trifolium repens L). The increase in the concentration of crude protein in the diet …
Species Preference Influences On Cattle Grazing Behaviour, G P. Cosgrove, C B. Anderson, R H. Fletcher
Species Preference Influences On Cattle Grazing Behaviour, G P. Cosgrove, C B. Anderson, R H. Fletcher
IGC Proceedings (1993-2023)
Lotus corniculatus offers specific nutritional benefits to animals, but exploiting these advantages in grazing systems depends on the proportion of lotus in the feed offered and the animals' preference, hence desire to select for it. To determine preference for lotus, heifers were offered free-choice in contrasting, spatially separated but adjacent monocultures of ryegrass-lotus or red clover-lotus. Following a one-week period to adjust to the species offered and their arrangement, 10 young heifers were observed at 10-minute intervals during daylight hours, and the species they were on and whether or not they were grazing was recorded. This procedure was conducted in …
Partial Preference Of Grazing Cattle For Contrasting Legume Swards, C.H. E.C. Poli, J Hodgson, G P. Cosgrove, G C. Arnold
Partial Preference Of Grazing Cattle For Contrasting Legume Swards, C.H. E.C. Poli, J Hodgson, G P. Cosgrove, G C. Arnold
IGC Proceedings (1993-2023)
Yearling heifers in groups of 3 grazed 405 m2 plots made up of alternating 2.4m wide strips of white clover/birdsfoot trefoil (WC+BT) or red clover (RC) in the proportions of 80:20, 67:33, 33:67 and 20:80 for periods of 3 days over four replicates in time, balanced for effects of previous treatment. Observation of the distribution of grazing activity and biting rate were made over 3 hour periods each evening. Biting rates were consistently higher on (WC+BT) than RC (52.3 vs 46.3 ± 0.59 bites.min-1 P(0.0001). Animals initially showed partial preference for the minor sward component in each treatment but regression …
The Use Of Vibration Analysis And Telemetry To Measure Bite Frequency And Intensity In Free-Ranging Horned Ruminants, P R. Lawrence, K Becker
The Use Of Vibration Analysis And Telemetry To Measure Bite Frequency And Intensity In Free-Ranging Horned Ruminants, P R. Lawrence, K Becker
IGC Proceedings (1993-2023)
An apparatus is described which detects and measures the vibrations in a ruminant’s horn especially those produced by the animal’s teeth. Vibrations are transmitted by radio to a portable computer where those produced as a result of eating and ruminating can be characterised by their intensity, length and frequency.
Influence Of Vegetation Patch Characteristics On Discriminatory Grazing By Dairy Cows, W M. Griffiths, J Hodgson, G C. Arnold, C W. Homes
Influence Of Vegetation Patch Characteristics On Discriminatory Grazing By Dairy Cows, W M. Griffiths, J Hodgson, G C. Arnold, C W. Homes
IGC Proceedings (1993-2023)
Two studies involving the sequential grazing of sets of patches on a perennial ryegrass (Lolium perenne) sward were carried out to investigate the effects of patch characteristics on the selective behaviour of grazing cattle. Experiment 1 involved a range of combinations of sward height (8.9 - 19.6 cm) and bulk density (1.33 - 1.67 mg DM/cm3). Distribution of grazing activity (number of bites or residence time) was strongly and positively related to patch height, but additional effects of variation in bulk density were limited. In Experiment 2 patches were manipulated to offer contrasts in both height (13.4 and …
Shade For Cattle On Pasture: A Guide For Ontario Producers, E J. Finegan, T M. Widowski
Shade For Cattle On Pasture: A Guide For Ontario Producers, E J. Finegan, T M. Widowski
IGC Proceedings (1993-2023)
In tropical climates, adequate shade may be essential to ensure the survival and productivity of grazing animals, but in the temperate Ontario climate, the necessity or benefits of providing shade for grazing cattle are less clear, and have proved controversial. Meteorological data indicate that beef cattle in Ontario may be at risk of suffering from heat stress on more than 25% of days during July and August, and may decrease feed intake and benefit from the provision of shade for more than 50% of days during the two hottest summer months. A booklet, entitled ‘Beat the Heat. A Guide …
Investigating Gulf Coast Aquifer System: Stratigraphy Reconstruction, Inverse Modeling, And Groundwater Stress Assessment, Shuo Yang
LSU Doctoral Dissertations
The Mississippi Embayment aquifer system (MEAS) and the Coastal Lowlands aquifer system (CLAS) provide substantial groundwater resources for human activities in the U.S. Gulf Coastal Plain. However, the overexploitation has led to groundwater depletion in the MEAS and the CLAS, threatening sustainable groundwater use. Such concern highlights the crucial need for an advanced understanding of stratigraphy and groundwater in these aquifer systems, which is essential for effective regional groundwater management. This dissertation presents a comprehensive investigation of MEAS and CLAS in the Louisiana and southwestern Mississippi region, encompassing three fundamental dimensions: stratigraphy reconstruction, groundwater modeling, and groundwater stress assessments. A …
Investigating The Causes Of Lake Level Variability On A Modern Carbonate Platform, Natalie M. Salazar
Investigating The Causes Of Lake Level Variability On A Modern Carbonate Platform, Natalie M. Salazar
USF Tampa Graduate Theses and Dissertations
Lakes on carbonate islands are known to reduce freshwater lens volumes and alter freshwater lens distribution; however, the magnitude and controlling factors between lake and freshwater lens interactions remain poorly understood. Since freshwater lenses are thin and can be fragmented by lakes in small carbonate islands, it is important to understand the magnitude of exchange between lakes and the freshwater lens to understand potential groundwater depletion. This study utilized high temporal resolution water levels and meteorological data to quantify monthly water budgets for seven lakes on San Salvador Island, The Bahamas. The monthly water budgets accounted for rainfall, potential evaporation, …
Comparative Life Cycle Assessment Of Copper Production, Xiaohan Wu
Comparative Life Cycle Assessment Of Copper Production, Xiaohan Wu
Graduate Industrial Research Symposium
Copper demand will surge significantly in the context of global renewable energy technology implementation, but its production is an energy-intensive process. It is crucial to choose the best production method to reduce environmental damage in terms of the enormous copper supply. This research develops a multi-criteria life cycle assessment model for the three main copper production routes- pyrometallurgy, hydrometallurgy, and bioleaching. We complied material and energy flow data to assess each route's life cycle greenhouse gas (GHG) emissions, cost, and resource efficiency. Results indicate bioleaching emits the least GHG emissions (4.09 kg-CO2 eq/kg copper) among the three routes. Hydrometallurgy is …
Identification Of Alfalfa Chromosomes Using Giemas Banding And Image Analysis Techniques, G R. Bauchan, M A. Hossain
Identification Of Alfalfa Chromosomes Using Giemas Banding And Image Analysis Techniques, G R. Bauchan, M A. Hossain
IGC Proceedings (1993-2023)
Chromosomes of two diploid (2n=2x=16) subspecies of Medicago sativa, ssp. caerulea and ssp. falcata, their hybrid and tetraploid (2n=4x=32) cultivated alfalfa (M. sativa, ssp. sativa) were studied. Feulgen’s staining, C- and N-banding techniques and an image analysis system were used. The chromosomes of ssp. falcata have only centromeric bands, however, a multitude of bands were observed in both the C- and N-banding pattern of ssp. caerulea and ssp. sativa enabling the precise identification of each of the eight sets of chromosomes and development of a karyotype. The differences in banding patterns between the diploid subspecies makes it possible …
Advances In Breeding Apomictic Brachiaria In Tropical America, J W. Miles, C B. Do Valle
Advances In Breeding Apomictic Brachiaria In Tropical America, J W. Miles, C B. Do Valle
IGC Proceedings (1993-2023)
Prior to 1988 Brachiaria improvement was based exclusively on the collection, introduction, and evaluation of natural germplasm from Africa. Breeding programs in Brachiaria have been possible only in the past 10 years with the creation of a sexual, tetraploid B. ruziziensis cross-compatible with B. decumbens and B. brizantha. Applied Brachiaria breeding projects are underway both in Colombia (International Center for Tropical Agriculture, CIAT) and Brazil (National Centre for Beef Cattle Research - Brazilian Corporation for Agricultural Research, CNPGC/EMBRAPA). These seek to combine the broad edaphic adaptation and other desirable agronomic attributes of B. decumbens cv. Basilisk with spittlebug resistance. An …
Evaluating Cultivars Of Subterranean Clover In Monoculture Or With Perennial Ryegrass, K F.M. Reed, S G. Clark, W M. Feely
Evaluating Cultivars Of Subterranean Clover In Monoculture Or With Perennial Ryegrass, K F.M. Reed, S G. Clark, W M. Feely
IGC Proceedings (1993-2023)
Over four years, sowing perennial ryegrass (Lolium perenne) with a range of subterranean clover (“sub clover”, Trifolium subterraneum) cultivars was found to reduce the yield of clover per se by 31% and increase pasture yield by 11%. For one high-producing experimental variety, the presence of grass did not reduce clover yield (P<0.001). Clover yield in monoculture plots was poorly correlated with that measured in mixed swards (r = 0.44), but clover yield (± grass) was correlated with total herbage yield (r = 0.94). Clover seed yield was not reduced by the presence of grass. However, in year 2 - but not in the establishment year - grass reduced seed weight. Irrespective of grass treatment, the new late maturing cultivar, Leura outyielded the other commercial cultivars (P<0.05). Enfield and Enfield x Daliak crosses set the most seed and regenerated with a greater density than other cultivars (P<0.05) - apart from Leura. It was concluded that the winter-active, late maturing cultivar, Leura, will compete most successfully with perennial ryegrass.
Gene Flow In Medicago Through Somatic Hybridization, S Arcioni, F Crea, O Calderini, F Damiani, P D. Cluster, F Pupilli
Gene Flow In Medicago Through Somatic Hybridization, S Arcioni, F Crea, O Calderini, F Damiani, P D. Cluster, F Pupilli
IGC Proceedings (1993-2023)
The objective of this research was the characterization at both molecular and phenotypic level of three somatic hybrid plants obtained by electrofusion of protoplasts of Medicago sativa with those of M.coerulea, M.falcata and M.arborea, three Medicago species in a different relation with alfalfa. Different kinds of rearrangements including the amplification of new spacer-length variants were detected at rDNA loci in the somatic hybrids. Analysis of field performances confirmed the suitability of these plants for breeding purposes.
Ssr- And Rapd Analysis Of A New Agropyron Repens Genotype, G Gyulai, H Ohm, I Dweikat, E Kiss, H Sharma, J Janovszky, L Heszky
Ssr- And Rapd Analysis Of A New Agropyron Repens Genotype, G Gyulai, H Ohm, I Dweikat, E Kiss, H Sharma, J Janovszky, L Heszky
IGC Proceedings (1993-2023)
SSR-(single sequence repeat), and RAPD (randomly amplified polymorphic DNA) primer generated DNA fingerprints were used to distinguish a new genotype of quackgrass from its original type of Agropyron repenes L. Beauv. (= Elytrigia repens). Products of polymerase chain reactions (PCR) were separated by agarose (AGE) and denaturing gradient gel electrophoresis (DGGE). Although, both kinds of primers were found to be polymorphic, the microsatellite primer with sequence of 5í-AC(GACA)4-3í generated distinguishing fingerprints in the two types of quackgrasses. This result gives genetic evidence for the new genotype of quackgrass.
Screening Ryegrass Cultivars For Aluminium Sensitivity In Nutrient Soluations, F O. Gallardo, S Benavides, R Demanet, F Borie
Screening Ryegrass Cultivars For Aluminium Sensitivity In Nutrient Soluations, F O. Gallardo, S Benavides, R Demanet, F Borie
IGC Proceedings (1993-2023)
The objective of this study was to evaluate Al and H+ tolerance of nine ryegrass (Lolium perenne and L. multiflorum) cultivars by growing plants in a mineral solution (pH 4.8 and 6.0 and 0-200 (M Al). Results showed that Yatsyn-1, with a relative root length of 91 was the cultivar least affected by acidity (H+), and Concord ( RRLpH = 58) was the cultivar with the highest H+ sensitivity. In connection with Al-tolerance, Yatsyn-1 and Concord, were the most tolerant cultivars with 88 and 87 RRLAl, respectively whereas Nui and Marathon, were the most sensitive ones, reaching only …