Rind Thickness Research Articles

Influence of Late-Lying Snow on Rock-Weathering Rinds

Spatial variation in weathering processes may produce differences in rock-weathering rind thickness; this is an important source of potential error in relative age dating. Data from a snow patch in the Colorado Front Range indicate that late-lying snow may increase rock-weathering thicknesses two to four times. Areas of maximum rind thickness appear where free water in the snowpack and subsequent meltwaters are concentrated. Differences of the magnitude re

Influence of Nitrogen, Phosphorus, and Potassium Applications on Stalk Quality Characteristics and Yield of Corn1

AbstractConsiderable work has been reported on the influence of fertilizer elements, particularly potassium, on yields and lodging of corn (Zea mays L.). Additional information is needed on the influence of other nutrients and different genotypes on stalk quality characteristics and yield. This paper reports the influence of four levels of nitrogen, phosphorus, and potassium on the percent of senescent stalks, crushing strength, rind thickness, stalk lodging, and yield of the six F1 hybrids of a four‐parent diallel of inbreds T101, T105, Till, and T115. The data were obtained using three independent experiments; one associated with each fertility element for 3 years. Nitrogen and phosphorus had little or no influence on stalk characteristics. Potassium additions reduced the percent of senescent stalks and stalk lodging and increased crushing strength and rind thickness. The influence of potassium on senescent stalks was dependent on the hybrid involved. Yield increased with additions of nitrogen and potassium, but phosphorus had little influence.

Correlation of Pith Cell Death with Various Stalk Quality Characteristics in Two Synthetic Populations of Maize1

Estimates of pith cell death in the first five elongated internodes of the stalk were obtained at midsilk and 3 weeks after midsilk in two synthetic maize (Zea mays L.) populations which had undergone three cycles of recurrent selection for high and low stalk quality. Significant correlations between rating periods and the first three successive internodes indicated that rating the first three internodes at midsilk accurately estimates pith cell death for these two populations.Four components of stalk quality, crushing strength, rind thickness, rind puncture, and weight of a 5.1‐cm internode section, were determined for both populations. Significant negative correlations were obtained between pith cell death ratings and each of the stalk quality components. Thus, internodal cell death ratings could be successfully and practically utilized in predicting stalk quality.

Recurrent Selection for Lodging Susceptibility and Resistance in Corn1

Recurrent selection was practiced for two corn synthetics, Syn 8 and Syn 9 (Zea mays L.), for lodging susceptibility (6 cycles) and lodging resistance (7 cycles) counting erect plants at maturity. Selection progress was evaluated using crosses between comparable cycles of the two synthetics and determining changes for the following traits: erect plants; ratings for root clump, rind puncture, and stalk rot; stem section dry weight, crushing strength, rind thickness, specific gravity, water content, and pith ratings; and yield and other agronomic characters. Compared with the cross of the original synthetics as 100%, the last cycle for susceptibility (cycle 6) had 28% as many erect plants and the last cycle for resistance (cycle 7) had 228% as many. Observed means for these comparisons were 40.3, 11.3, and 91.9% erect plants, respectively. All possible simple correlation coefficients among the stalk and root quality traits were significant at the 1% level except for pith ratings. The use of a single selection criterion (erect plants) insured that associated changes in other traits were not confounded by other conscious selection.

Effects of Diplodia Stalk Rot on Stalk Quality in Corn (Zea mays L.)1

Four single crosses in corn (Zea mays L.), representing a wide range in stalk‐lodging resistance, were evaluated for reaction to Diploidia maydis (Berk.) in Experiment I. Crushing strength and rind‐thickness values were higher in the lodgingresistant and intermediate single crosses than in the two lodgingsusceptible crosses. Increased stalk rotting, resulting from inoculation with D. maydis, greatly affected crushing strength and stalk rot ratings but had no significant effect on rind thickness. Reductions in crushing strength due to D. maydis were substantially greater for two lodging‐susceptible single crosses than for an intermediate or a resistant one. The two lodging‐susceptible single crosses were also susceptible to D. maydis.In Experiment II the crushing strength, weight of 5.1‐cm stalk section, and rind thickness were reduced and stalk‐rot ratings increased as plant‐population densities were increased. Crushing strength of the lodging‐resistant single cross was weakened nearly as much as a lodging‐susceptible single cross by D. maydis. Stalk‐rot intensity was negatively correlated with crushing strength. Weight of section and rind thickness were positively correlated with stalk crushing strength. Stalk rot (as a component of crushing strength) was relatively independent of rind thickness and stalk weight. Data from these experiments show that Diplodia is an important variable contributing to stalk quality and has an effect in reducing crushing strength but is relatively independent of rind thickness and weight of stalk section.

Diallel Analysis of Stalk Quality Traits in Twelve Inbred Lines of Maize1

Sixty‐six inter se F1 crosses among 12 inbred lines of corn (Zea mays L.) were evaluated in two years at two locations. The inheritance of eight stalk traits was determined by means of diallel analysis. Significant differences among the 66 F1 hybrids were obtained in each trait. General combining ability (gca) and specific combining ability (sca) mean squares were statistically significant nearly every instance. The gca mean square was usually much larger than the sea mean square. Genotypic correlation coefficients between large stalk diameter and crushing strength, weight of stalk and crushing strength, and rind thickness and crushing strength were .72, .88, and .60, respectively. Weight of stalk section appears to be well suited for rapid screening purposes, whereas stalk density appears to be a poor trait to employ in a selection program. for the material studied, selection for high crushing strength will likely result, on the average, in strains characterized by increased size of stalk, weight of stalk, and thickness of rind. Selection procedures recommended for populations involving the lines tested were those which are effective in utilizing both the additive and nonadditive genetic variability.

Genetic Variation of Four Anatomical Traits and Their Association with Stalk Quality Traits in Maize (Zea mays L.)1

Stalk quality traits, including crushing strength and rind thickness, were evaluated in 1967 and 1968. In addition, four anatomical traits of the stalk were evaluated in 1967 for 66 inter se crosses among 12 inbred lines of maize (Zea mays L.). The nature of the genetic variation of (i) area of the stalk cross‐section, (ii) area of rind, (iii) of pith, and (iv) the number of vascular bundles in the pith were determined by means of diallel analysis. Significant differences among the 66 F1 hybrids were obtained in each trait. General combining ability (gca) mean squares were significant in each instance, whereas specific combining ability (sca) mean squares were small and not statistically significant. Low genotypic correlation coefficients among three of the four characters studied and traits known to be diagnostic of stalk strength indicated that stalk cross‐section, pith area, and bundle number in the pith would have linfited merit in a selection program. Genotypic correlation coefficients of rind area with diagnostic stalk quality traits were higher, but rind area determinations would be prohibitively expensive and time consuming. The number of vascular bundles in the pith was a poor indicator of stalk strength. We concluded that rind attributes were better indicators of stalk strength than were traits associated with the pith of maize stalks.

Appearance and Quality Characters in Muskmelon Fruit Evaluated by a Ten-Cultivar Diallel Cross1

Abstract Ten cultivars of muskmelon were evaluated in a diallel cross at 3 locations during a single season for net appearance, absence of vein tract depression (sutures), rind thickness, percent soluble solids, percent flesh, and shape index (length/width). Variances among crosses were significant for all traits. Significant heterosis was favorable for percent soluble solids, but unfavorable for net appearance and shape index. General combining ability accounted for a greater portion of the variability among crosses than did specific combining ability, although both effects were highly significant for each of the traits. Crosses correlated favorably with cultivar performance for net appearance, vein tracts, and percent flesh. The combination of certain cultivars into a synthetic population for further improvement of muskmelon is discussed.

Tree Spacing of ‘Washington’ Navel Orange1,2

Abstract In 1961, trees of Frost Nucellar ‘Washington’ navel orange on Troyer Citrange rootstock were planted at eleven different spacings to determine the effect of tree spacing on growth, production, and fruit quality. Growth rate as measured by trunk circumference was proportional to decreasing tree density or increased spacing. The wider the spacing, the greater was the trunk circumference and the fruit-bearing capacity of the tree. Shading of skirt foliage, as closely planted trees began to crowd, caused the skirts to die and decreased production. Pruning to keep these trees from crowding reduced yield in proportion to the amount of foliage removed. Removal of alternate trees in the two most densely planted spacings, 9 ft. × 11 ft. and 11 ft. × 11 ft., reduced competition and allowed more light to reach the remaining trees. Skirt foliage regrew and yield per-tree and per-acre increased. Fruit colored faster and was larger on the widely spaced trees, where less shading had occurred, than on closely spaced trees. Fruit quality analysis showed no difference in percent of juice, soluble solids, acid, or rag, or in peel and rind thickness. The closest spacings, 9 ft. × 11 ft., 9 ft. × 15 ft. and 11 ft. × 11 ft., operated at a net loss for the first five years of production. Although per tree production was highest on the widest spacing, 22 ft. × 22 ft., net returns per acre on this spacing are still low because of the number of trees per acre. The 11 ft. × 22 ft. spacing with 180 trees per acre had the largest net income per acre.

Association between certain stalk traits related to lodging and grain yield in maize (Zea mays L.)

Thirty-five varieties of maize from different ecogeographical regions were planted to study the relationship between stalk characters and grain yield in maize. Grain yield was positively correlated with three stalk traits under investigation. Highly significant positive correlations existed among weight of a 5 cm stalk section, crushing strength and rind thickness. In general, genotypic correlation coefficients were higher than the phenotypic correlation coefficients. The present study indicates that it is possible to develop a high-yielding variety with superior stalk strength.

Specific Gravity of Corn Stem Sections1

Specific gravity (dry), i.e., dry weight/green volume, of 50‐mm stem sections of corn (Zea mays L.) was significantly correlated with stalk lodging, stalk rot rating, crushing strength, rind thickness, and puncture rating. Dry weight of sections was similarly correlated. Two other types of specific gravity (green and absolute) were generally not as well correlated. Specific gravity and dry weight evaluations were obtained approximately 1 month after pollination, were determined independntly of lodging stress, and were useful measures of stalk strength.

Relationship of Certain Stalk Characters with Grain Yield in Corn (Zea mays L.)1

Previous studies have shown stalk quality in corn, Zea mays L., as measured by rind thickness and crushing strength, is highly correlated with field stalk lodging. Some corn researchers question if increasing rind thickness, weight of a 5.1‐cm section and crushing strength through breeding and selection might have an effect on grain yield. This study, employing the S0 and S1 progenies from the F2 and first and second backcross generation of two inbred lines, showed little, if any, genetic correlation between three stalk‐traits and yield. Since our study was limited to only two inbred parents additional studies should be conducted with larger randomly‐sampled populations tested over several environments to confirm whether a relationship exists. However, our results suggest to us that we would have little difficulty in developing high yielding lines with good stalk quality from the progenies of the two inbred parents, ‘Mo22’ and ‘Mo940.’

Total Ash and Potassium Content of Stalks as Related to Stalk Strength in Corn (Zea mays L.)1

AbstractThis study was conducted to augment and elucidate results of previous studies with corn which indicated that stalk lodging was positively correlated with ash, potassium, and silicon content of mature stalks. Six stalklodging susceptible and 6 stalk‐lodging resistant inbreds were tested in replicated experiments at 2 locations for 3 years. Total ash and potassium content of mature stalks were determined. The total ash content of the 6 stalk‐lodging resistant lines was smaller than for the 6 stalk‐lodging susceptible lines, and differences between the 2 groups were very large. Potassium content followed about the same pattern as ash content and accounted for about 25% of the ash. Agreement between locations and years‐within‐locations was excellent. The ranking of the 12 inbred lines by ash and potassium content was relatively consistent regardless of year or location. Significant negative correlations were found between ash content and crushing strength, and rind thickness and weight of a 2‐inch section. The association of high ash content with stalk‐lodging susceptible lines supports the findings of earlier studies which indicated a negative relationship between actual field stalk lodging and the three stalk traits evaluated here. The correlation coefficients between potassium and the three stalk traits were negative but none was statistically significant.

Effects of Years and Locations on Stalk Strength in Corn (Zea mays L.)1

AbstractNegative correlations between crushing strength of mature corn stalks and field stalk lodging have been shown by several workers. The objective of the study reported here was to determine the relative effects of years and locations on stalk‐crushing strength, rind thickness, and weight of 2‐inch stalk sections. Twelve inbred lines representing a wide range in inherent stalk lodging performance were grown at two locations for a 3‐year period. Data for the three stalk traits indicated a good agreement between locations within years while crushing strength and rind thickness varied more between years. Variation in crushing strength was attributed in part to pith destruction by stalk rots which are more prevalent in some seasons than in others. It was concluded that stalk quality data obtained in a single year at a single location would usually be adequate to screen a group of strains for inherent stalk lodging resistance. For greater precision data for more than one year and one location would be necessary. Crushing strength was affected more by different environments than the other two traits. The coefficients of variation for crushing strength ranged from 11.7 to 18.8%; rind thickness from 5.2 to 8.5% and weight of 2‐inch section from 8.7 to 13.0%.

Stalk Strength of Strains of Maize of Colombia, Ecuador, and Venezuela as Measured by Rind Thickness1

Crop ScienceVolume 6, Issue 2 cropsci1966.0011183X000600020033x p. 210-211 Brief Articles Stalk Strength of Strains of Maize of Colombia, Ecuador, and Venezuela as Measured by Rind Thickness1 Paul L. Crane, Paul L. CraneSearch for more papers by this authorDiaz B. Efrain, Diaz B. EfrainSearch for more papers by this authorA. Rivera G. Jesus, A. Rivera G. JesusSearch for more papers by this authorC. Toro M. Julio, C. Toro M. Julio Associate Professor of Agronomy, Purdue University Agr. Exp. Sta., and Agronomists, Instituto Colombiano Agropecuario.Search for more papers by this author Paul L. Crane, Paul L. CraneSearch for more papers by this authorDiaz B. Efrain, Diaz B. EfrainSearch for more papers by this authorA. Rivera G. Jesus, A. Rivera G. JesusSearch for more papers by this authorC. Toro M. Julio, C. Toro M. Julio Associate Professor of Agronomy, Purdue University Agr. Exp. Sta., and Agronomists, Instituto Colombiano Agropecuario.Search for more papers by this author First published: 01 March 1966 https://doi.org/10.2135/cropsci1966.0011183X000600020033x 1 Paper No. 178 of the Agricultural Journal Series of the Rockefeller Foundation. Research accomplished through the cooperation of the Rockefeller Foundation, Instituto Colombiano Agropecuario and Purdue University. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume6, Issue2March–April 1966Pages 210-211 RelatedInformation

Stalk Strength of Corn as Measured by Crushing Strength and Rind Thickness1

Stalk Strength of Corn as Measured by Crushing Strength and Rind Thickness¹

Inheritance of Crushing Strength and Rind Thickness in Several Inbred Lines of Corn1

Crop ScienceVolume 3, Issue 2 cropsci1963.0011183X000300020025x p. 173-174 Article Inheritance of Crushing Strength and Rind Thickness in Several Inbred Lines of Corn1 P. J. Loesch Jr., P. J. Loesch Jr.Search for more papers by this authorM. S. Zuber, M. S. ZuberSearch for more papers by this authorC. O. Grogan, C. O. Grogan Geneticist and Research Agronomists, ARS, USDA, and Research Associates, Department of Field Crops, University of Missouri. (Grogan now located at Mississippi State University.)Search for more papers by this author P. J. Loesch Jr., P. J. Loesch Jr.Search for more papers by this authorM. S. Zuber, M. S. ZuberSearch for more papers by this authorC. O. Grogan, C. O. Grogan Geneticist and Research Agronomists, ARS, USDA, and Research Associates, Department of Field Crops, University of Missouri. (Grogan now located at Mississippi State University.)Search for more papers by this author First published: 01 March 1963 https://doi.org/10.2135/cropsci1963.0011183X000300020025xCitations: 4 1 Joint contribution from the Crops Research Division, ARS, USDA, and the Department of Field Crops, University of Missouri Agricultural Experiment Station, Journal Series Number 2475. Approved by the Director August 8, 1962. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume3, Issue2March–April 1963Pages 173-174 RelatedInformation