Category Archives: Volume 8 No. 1 (1986)
Recovery and Growth Patterns of Coastal Bermuda Grass as Influenced by Nitrogen Level and Defoliation Frequency
Author(s): M.R. Villanueva and E.C. Holt
Abstract
The interrelationships among residual leaf area following defoliation, leaf area development patterns and mean crop growth rates of Coastal bermuda grass as influenced by nitrogen levels (20, 50 and 100 kg/ha/mo) and defoliation frequency (2, 4, and 8-week intervals) were evaluated. Residual leaf area index (LAI), dry matter (DM), LAI accumulation at weekly intervals, and mean crop growth rate (CGR) were determined.
During the first 2 weeks, DM development was more rapid following more frequent defoliation and at higher N rates. The effect of N on DM accumulation increased after the first 2 weeks and DM did not peak in any of the harvest intervals. Residual LAI was greater with more frequent harvest, but LAI evolution was not significantly influenced by N until the sixth week. Initial regrowth, however, appeared to be related more to N than to residual LAI. Higher N and more frequent defoliation produced denser turf which in turn provided more sites for origin of new leaves and this seems to be more important for rapid regrowth than residual leaves. Mean crop growth rate in all harvest frequencies significantly increased from the first to the second week and was considerably higher with increasing harvest frequencies. Since N was applied at 4-week intervals, these results suggest that N applications more frequent than at 4-week intervals and at rates higher than 100 kg/ha/mo, are required to maximize growth of Coastal bermuda grass.
Keywords : Cynodon dactylon (L.) Pers. Leaf area index (LAD. Mean crop growth rate (CGR). Dry matter. Nitrogen levels. Defoliation.
Soy Sauce Production Utilizing Root Crop Flour as Substitute for Wheat Flour (100% Substitution)
Author(s): Emma S. Data, Julie C. Diamante and Edna E. Forio
Abstract
Soy sauce yield was not affected by the substitution of wheat flour with root crop flour as carbohydrate source for the fermentation micro-organisms. The titratable acidity, pH and NaCl content were not significantly affected by flour substitution while the protein content and amino nitrogen of root crop-based soy sauce were lower than that of sauce produced from wheat flour.
Sensory evaluation showed that when soy sauce was used in preparing beef steak or as dip for broiled fish, root crop-based soy sauce was comparable to one commercial brand based on general acceptability scores. Cooked sweet potato-based soy sauce was comparable to two commercial brands when served as pure soy sauce based on color, aroma, consistency and flavor.
Keywords : Soy sauce. Wheat substitution. Root crop flour. Soybean. Fermentation. Aspergillus oryzae. Aspergillus sojae.
Fungal Infection and its Effect on Stored Sun-Dried and Kiln-Dried Copra
Author(s): Albert P. Morante, Manuel K. Palomar and Jesusito L. Lim
Abstract
Moisture content and meat surface cleanliness of stored copra influenced the occurrence, growth and abundance of fungi. Aspergillus niger, A. oryzae, A. tamarii, A. flavus var. columnaris, Penicillium nigricans and P. bialoweinzense were found to infect sun-dried copra. Except for the absence of A. niger, the same species were found to infect the stored samples of kiln-dried copra. In addition to the aforementioned species, A. heteromorphus, A. tubigensis, A. flavus and Rhizopus nigricans were observed to infect copra collected from warehouses in Baybay, Leyte, The presence of fungi on copra attracted insect pests which caused additional damage such as holes in the meat and accumulation of copra “dust”.
The color of the oil obtained from infected sun-dried and kiln-dried copra was darker than that of oil obtained from uninfected copra indicating that the presence of fungi during storage might have affected the quality of the oil. The drying method had no effect on the quantity of oil extracted before storage as shown by the comparable amount of oil obtained from sun-dried and kiln-dried copra. Even after 3 months of storage, there was no significant difference in the quantity of oil extracted from infected and uninfected sun-dried and kiln-dried copra.
Keywords : Copra. Sun-dried. Kiln-dried. Moisture content. Oil content. Fungal infection.
Identification of High Acetic Acid-Yielding Bacteria from Nipa Sap
Author: Julie C. Diamante
Abstract
Eighteen gram-negative bacilli and cocci were selected from 40 isolates in naturally fermenting nipa sap from Paombong, Bulacan. When grown and screened in pasteurized nipa sap, 10 high acetic acid-yielding isolates were further selected. Based on their morphological and physiological characteristics, they were identified as Acetobacter aceti subsp. aceti, A. paradoxus subsp. paradoxus, six isolates of A. ascendens subsp. ascendens, A. lovaniensis subsp. lovaniensis and A. rancens subsp. pasteurianus.
Among the identified bacteria, A. aceti subsp. aceti produced the highest amount of acetic acid in pasteurized nipa sap. This bacterium responded positively to most of the physiological tests that were used. The utilization of glucose, ethanol and other nutrients by bacteria for acetic acid production was found to be dependent on their physiological characteristics.
Keywords : Acetic acid bacteria. Screening. Identification. Morphology. Physiology. Fermentation. Nipa (Nypa fruticans) sap.
Life History and Behavior of the Fig Moth, Cadra cautella Walker, as Affected by Varying Moisture Levels of Copra
Author(s): Rowena V. Paglinawan and Lorenza B. de Pedro
Abstract
Life cycle was longer, and fecundity of females and percent hatchability of eggs were lower when moths were reared on copra with 3 to 40% moisture content than when they were reared on substrates with 5 to 14% moisture content. Longevity, feeding, mating and oviposition behavior of adults were not significantly affected by the moisture levels tested. No significant difference in the life history of the insect was observed during the first and second generation.
Keywords : Cadra cautella Walker. Lite history. Behavior.Moisture level.
Cytokinin-Like and Growth-Promoting Activity of Coconut Water as Related to its Effect on Pole Sitao Pod Deterioration
Author(s): A.L. Acebedo, Jr. and O.K. Bautista
Abstract
Cytokinin-like activity of coconut water was highest from 12-month old nuts and lowest from 8-month old nuts. Total growth-promoting activity showed a similar trend but was generally greater indicating the possible presence of other contributory compounds.
Coconut water from 10- and 12-month old nuts markedly retarded yellowing and chlorophyll loss in pole sitao pods. However, only the latter significantly improved the visual quality of the pods. All treatments did not affect weight loss- and the textural properties of the pods. A slight stimulation of the respiratory activity was observed in all coconut water-treated pods.
Keywords : Pole sitao (Vigna sesquipedalis Fruw.). Pod deterioration. Coconut water. Stages of nut maturity. Cytokinin-like and growth-promoting activity.