scholarly journals Failure of preharvest foliage sprays with 2, 4-d and maleic hydrazide to affect the sucrose content of sugarcane

1969 ◽  
Vol 37 (1) ◽  
pp. 44-51
Author(s):  
M. A. Lugo-López ◽  
G. Samuels ◽  
R. Grant
Keyword(s):  
Puerto Rico ◽  
Seasonal Variations ◽  
Field Experiments ◽  
Maleic Hydrazide ◽  
Rio Grande ◽  
Weather Conditions ◽  
Sucrose Content ◽  
East Central ◽  
The Mean

Data are presented here on the effect of applications of 2,4-D and maleic hydrazide to sugarcane at intervals prior to harvesttime. Field experiments were conducted at Río Piedras in northern Puerto Rico and at Colonia Río Grande, between Caguas and Gurabo, in east-central Puerto Rico. Daily fluctuations in Brix, polarization, purity, and available 96° sugar percent cane were followed for 46- and 72-day periods, respectively. No significant differences were observed between the mean available 96° sugar percent cane that could be ascribed to treatments. Seasonal variations and variations attributable to weather conditions were rather important factors at both locations.

scholarly journals Effects of different fertilization practices on the glucose, fructose, sucrose, taste and texture of carrot

1989 ◽  
Vol 61 (2) ◽  
pp. 113-122
Author(s):  
Aino-Maija Evers
Keyword(s):  
High Performance ◽  
Field Experiments ◽  
Sugar Content ◽  
Weather Conditions ◽  
Total Sugar ◽  
Sucrose Content ◽  
Glucose Content ◽  
Total Sugar Content ◽  
Contrast Analysis ◽  
The Mean

The effects of different fertilization practices on the glucose, fructose, sucrose, taste and texture of carrot cv. Nantes Duke Notabene 370 Sv were studied in field experiments carried out in southern Finland in 1985 and 1986. The effects of unirrigated and irrigated placement and broadcast fertilization, NPK fertirrigations without basic fertilization, NPK fertirrigations with NPK basic fertilization, and PK placement with N fertirrigations were compared. Further, the effects of single application were compared with those of split applications. Sugar analyses were made by high performance liquid chromatography, and sensory evaluations were performed for taste and texture. The results were analysed by contrast analysis. In 1985, fertilization and fertilization practices had no effects on sugar contents. In 1986, the unfertilized treatments had a tendency to yield higher glucose and fructose, and thus also total sugar contents than did the fertilized treatments on the average. Placement fertilization had a tendency to increase the glucose content as compared to NPK fertirrigations. No significant differences or tendencies were found in sucrose content. The glucose and fructose contents were higher in 1985 than in 1986. The sucrose content was mainly opposite, being higher in 1986.Weather conditions were more favourable for photosynthesis in 1986 than in 1985. The mean total sugar content in fresh weight was 7.8 % in 1985 and 6.7 % in 1986. Indicative results of taste and texture are presented. The sugar content in organically cultivated carrots did not differ from that of conventionally grown carrots, but the taste was worse.

scholarly journals Field Reaction of Landrace Components of Red Mottled Beans to Common Bacterial Blight

HortScience ◽  
1992 ◽  
Vol 27 (1) ◽  
pp. 50-51 ◽  
Author(s):  
James S. Beaver ◽  
James R. Steadman ◽  
Dermot P. Coyne
Keyword(s):  
Puerto Rico ◽  
Phaseolus Vulgaris ◽  
Bacterial Blight ◽  
Xanthomonas Campestris ◽  
Field Experiments ◽  
Common Bacterial Blight ◽  
Sources Of Resistance ◽  
Growing Seasons ◽  
Field Reaction ◽  
The Mean

Field reaction of 25 red mottled bean (Phaseolus vulgaris L.) genotypes to common bacterial blight [Xanthomonas campestris pv. phaseoli (Smith) Dye] was evaluated in Puerto Rico over 2 years. The average disease severity (percent leaf area with symptoms) was similar over years. The determinate red mottled genotypes had almost twice as much disease as indeterminate genotypes. Eight of the indeterminate genotypes had significantly less disease than the mean of the field experiments. These genotypes may serve as useful sources of resistance to common bacterial blight. The size of the chlorotic zone around necrotic lesions varied between growing seasons, showing that environment can influence the expression of common bacterial blight symptoms.

scholarly journals Factors affecting the sucrose content of sugarcane: iii, varieties

1969 ◽  
Vol 37 (1) ◽  
pp. 28-34
Author(s):  
M. A. Lugo-López ◽  
G. Samuels ◽  
F. Méndez
Keyword(s):  
Puerto Rico ◽  
Seasonal Variation ◽  
Field Experiments ◽  
Total Sugar ◽  
Sucrose Content ◽  
Climatic Region ◽  
Land Area ◽  
Seasonal Differences ◽  
Factors Affecting ◽  
Climatic Regions

Data were obtained from 41 field experiments located throughout the Island. From the whole group of varieties tested, 20 were selected for evaluation of their sucrose production at harvesttime. The data were grouped according to three broad climatic areas, namely, humid, subhumid, and semiarid. Certain varieties were observed to produce better sucrose yields in a given climatic region, but in general, there were no significant differences among climatic regions for most varieties. P.R.'s 908, 907, 902, and 905, M.'s 330 and 28, and C.A.'s 38-102 and 38-74 produced the highest sucrose yields at harvesttime. The superiority in this respect of M.'s 336 and 28, and P.R.'s 907, 902, and 905 has been definitely established. Other promising varieties need further testing. Most of these canes yield more total sugar than the standard commercial P.O.J. 2878 and B.H. 10-12 canes, which cover more than 80 percent of the total land area where sugarcane is grown in Puerto Rico. The important bearing of seasonal variation on sucrose content of varieties is discussed. Seasonal differences in the performance of individual varieties have proved to be much greater than differences encountered between varieties in the same season.

scholarly journals The Effect of Soil Conditions on the Sucrose Content of Sugarcane

1969 ◽  
Vol 38 (3) ◽  
pp. 132-146
Author(s):  
M. A. Lugo-López
Keyword(s):  
Puerto Rico ◽  
Chemical Reaction ◽  
Climatic Conditions ◽  
Soil Types ◽  
Soil Conditions ◽  
Sucrose Content ◽  
East Central ◽  
Sugarcane Varieties ◽  
Edaphic Conditions ◽  
Different Soils

Data are presented herein to show the influence of soils and soil conditions on the sucrose yield of sugarcane. Information derived from five broad geographic areas of Puerto Rico, namely: North, south, northeast, east-central, and northwest-interior, was analyzed critically. There were significant differences in the sucrose-yielding potential of several commercial sugarcane varieties among some soils within each area. These differences are attributable to variations in the properties of the various soil types or complexes, or to some factor closely connected with the soil like drainage, chemical reaction, and so on. Some varieties produced higher sucrose yields than others even when growing under similar edaphic conditions. Different varieties of sugarcane produced their maximum yields in different soils, thus indicating a certain degree of variability and adaptation to the soil, as far as this factor was concerned. Within a given area the sucrose-yielding potential of a given soil may be modified considerably by the dominant climatic conditions.

Evaluation and Acceptability of Cassava Cultivars

1969 ◽  
Vol 67 (1) ◽  
pp. 16-21
Author(s):  
Oscar D. Ramírez ◽  
José J. Green ◽  
Isabel Beauchamp de Caloni
Keyword(s):  
Puerto Rico ◽  
Hydrocyanic Acid ◽  
Preliminary Evaluation ◽  
Manihot Esculenta Crantz ◽  
Organoleptic Evaluation ◽  
East Central ◽  
Mean Values ◽  
Overall Acceptability ◽  
The Mean ◽  
Toxicity Level

On the basis of yield and organoleptic evaluation, out of 10 cassava (Manihot esculenta Crantz) cultivars, IAC-12-829, IAC-Mantequeira, Jamaica 18 and Trinidad 14-56 are the most promising in this preliminary evaluation. The 10 cassava cultivars were evaluated in the hilly humid East Central region of Puerto Rico. The highest yielders were IAC 12-829, IAC-Mantequeira, Jamaica 18, and SRT-598-Sta. Catarina with 41.98, 39.24, 35.17 and 31 .13 tons/ha, respectively. Hydrocyanic acid content among cultivars was well below the toxicity level (50-100 mg/kg). The mean values ranged from 0.0 up to 22.3 mg HCN/kg of fresh peeled root. Regarding overall acceptability by the tasting panel all except Sta. Catarina cultivar were acceptable.

scholarly journals Influence of abiotic factors on spring oat yields in the Northern region of Russian Federation

2020 ◽  
Vol 15 (3) ◽  
pp. 263-271
Author(s):  
Irina Valentinovna Zobnina ◽  
Valentina Aleksandrovna Korelina ◽  
Olga Borisovna Batakova
Keyword(s):  
Russian Federation ◽  
Field Experiments ◽  
Abiotic Factors ◽  
Weather Conditions ◽  
Northern Region ◽  
Weak Correlation ◽  
High Productivity ◽  
Grain Productivity ◽  
The Russian Federation ◽  
The Mean

Field experiments were carried out on sod-podzolic medium loamy soil, typical for the Northern region of the Russian Federation, in 2012-2019. The dependence of spring oat yields on abiotic conditions was studied. During the research years, the weather conditions varied significantly, which affected the productivity of spring oat. The yield of spring oat grain was found to have a very weak correlation with the effective temperature sum, weak correlation - with the total precipitation, and negative correlation - with the mean air temperature, which indicates the possibility of seed production of this crop in the Northern region of the Russian Federation. According to the data obtained, grain yields varied significantly from year to year. The reasons for the decline in grain productivity in individual years were different and complex. The most plastic cultivars with high productivity were identified.

scholarly journals Evaluation of Chemical Ripeners for Sugarcane

1969 ◽  
Vol 56 (4) ◽  
pp. 370-396
Author(s):  
G. Samuels ◽  
A. Vélez ◽  
R. A. Yates ◽  
B. Walker
Keyword(s):  
Puerto Rico ◽  
Gibberellic Acid ◽  
Standard Error ◽  
Field Experiments ◽  
Chemical Compounds ◽  
Northern Coast ◽  
Southern Coast ◽  
Rainy Weather ◽  
Small Plot ◽  
The Mean

Eight chemical compounds were evaluated in 13 field experiments to determine if they could ripen sugarcane at the end of the harvest season, May-June 1970, on the humid northern coast (Loíza) and the irrigated southern coast (Aguirre and Mercedita) of Puerto Rico. C.P. 41845 (Monsanto) ripened sugarcane at Loíza and Mercedita when the control plots indicated dropping sucrose and purity values due to rainy weather. There were significant increases with the 2- and 4-pound per acre applications for pol, Brix and sucrose-percent-cane for the mean of the 6-week period after application. At Aguirre, there were no significant increases in sucrose components for individual samples or mean of all sampling dates. The control plots for this trial showed increasing sucrose and purity levels for the 6-week period. Pesco 1815 at 1.5-pound and 60CS16 at 0.5-pound per acre rates gave positive increases in the sucrose components, Brix, sucrose-percent-cane and purity at Mercedita, but not at Loíza. The results suggest that the success or failure of these three compounds to ripen the cane at the various experimental sites may depend on the degree and tendency of maturity of the cane. Cane with low or dropping sucrose and purity levels responded to the ripening compounds, whereas cane with naturally high or increasing sucrose or purity values failed to respond. Gibberellic acid, Dalapon, Silicon, Ethrel 68-250 and Cycocel failed to give significant increases in pol-percent-cane, Brix, sucrose-percent-cane or purity. The experimental techniques of applying sprays with a pneumatic-type tank equipped with a long lance for small-plot experimentation was discussed. To reduce the standard error it is suggested that the number of replications be increased and care taken in selecting plots for uniform stand and with a minimum of lodged cane.

scholarly journals The Influence of Potassium on the Yield and Sucrose Content of Sugarcane

1969 ◽  
Vol 38 (4) ◽  
pp. 170-178
Author(s):  
George Samuels ◽  
Pablo Landrau, Jr.
Keyword(s):  
Puerto Rico ◽  
Field Experiments ◽  
Sucrose Concentration ◽  
Dry Weight ◽  
Percentage Increase ◽  
Sucrose Content ◽  
Podzolic Soils ◽  
Cane Juice ◽  
Foliar Diagnosis ◽  
The University

Critical analysis of the results of over 200 field experiments with potash fertilizers on sugarcane conducted by the Agricultural Experiment Station of the University of Puerto Rico, covering a wide ranges of cane varieties and sons types of Puerto Rico, revealed the following: (1) Potash increased cane yields mainly on the red and yellow podzolic soils of the humid area and on a planosol of the semiarid area. There was slight, if any, response to potash in the irrigated area. (2) The use of potash increased the sucrose concentration of the cane only if cane yields were also increased. Increases of 10 percent or more in tonnage were required if increases in sucrose content were to be expected. A linear relation Y = 0.12 x + 0.55 was obtained where Y was the percentage increase in sucrose-percent-cane and x the percentage increase in tons of cane yielded per acre. (3) When potash fertilizers significantly influenced the sucrose concentration of the cane, the polarization value of the cane juice increased. Brix and percentage extractability of juice were not appreciably affected. (4) The use of foliar diagnosis has proven to be of great value in Puerto Rico in determining when to apply potash fertilizers to sugarcane. Leaf values of 2 percent or more, on a dry-weight basis, indicate that no response to potash applications can be expected for soils and varieties in Puerto Rico. Values below 1.80 percent indicate that a response to potash fertilizers may be expected in the humid areas.

Vertical Topsoiling, A Practicable Technique to Manage Soils with Markedly Compact Subsoils

1969 ◽  
Vol 57 (3) ◽  
pp. 186-195
Author(s):  
Raúl Pérez Escolar ◽  
César Ortiz Lugo
Keyword(s):  
Puerto Rico ◽  
Field Experiments ◽  
Clay Soil ◽  
Water Infiltration ◽  
Root Penetration ◽  
East Central ◽  
Infiltration Rates ◽  
Percent Increase ◽  
Modification Technique ◽  
Deep Plowing

The effects of vertical topsoiling, vertical mulching, deep plowing and a combination of vertical mulching and deep plowing were studied in field experiments conducted on a Mabí clay soil, a Vertisol in east-central Puerto Rico. The results obtained in these experiments indicate that any mechanical soil modification technique that disturbs the subsoil of Mabí clay and similar soils, which comprise around 90,000 acres in Puerto Rico, tends to increase sugarcane and corn yields. Vertical mulching and deep plowing resulted in significant increases of 0.5 tons of sugar over the control in the first cane crop, whereas vertical topsoiling resulted in significant and highly significant increases of 0.5 and 0.64 tons in the first and second crop, respectively. Water infiltration rates were generally 2 to 3 times higher in the vertical mulching and vertical topsoiling plots than in the control although the differences were not statistically significant due to extreme variations. A combination of deep plowing and vertical mulching resulted in a 70-percent increase of shelled Mayorbela corn over the control, while vertical topsoiling alone produced a 57-percent increase. Vertical topsoiling induced abundant root penetration to a depth of 30 inches whereas roots in the control were confined mostly to a depth rarely exceeding 10 inches.

scholarly journals The Effect of Weather and Climate on the Sucrose Content of Sugarcane

1969 ◽  
Vol 38 (4) ◽  
pp. 149-169
Author(s):  
M. A. Lugo-López ◽  
B. G. Capó
Keyword(s):  
Puerto Rico ◽  
Climatic Factors ◽  
Weather Conditions ◽  
The Other ◽  
Sucrose Content ◽  
The West ◽  
Weather And Climate

In the endeavor to ascertain the influence of some specific weather and climatic factors on the sucrose content of sugarcane at harvesttime in Puerto Rico, data on past crops of such commercial varieties as, P.R. 902, M. 28, P.R. 905, P.O.J. 2878, and others, were re-examined and re-evaluated. There were significant variations in the sucrose content of the same varieties when grown in the same regions in different crop years. These variations were related to weather conditions. Canes harvested at southern irrigated plantations with low rainfall consistently yielded more sucrose than those grown elsewhere, while those grown in the west were higher in sucrose than those grown in the interior, north, or east. In the former region field-irrigation schedules provide for a drying out of the cane from 45 to 60 days before harvest, while the cane was normally harvested during the drier season of the year in the other regions mentioned.

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