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ARTICLE DIGESTS
Philipp. Agric. Scientist 87: 9-13
(2004)
Genetic Variation of Native
Horses (Equus caballus Linn.) in Laguna,
Philippines Based on Protein/Isozyme and Morphometric Analyses
M. B. Valdez1,
F. F. Peñalba2,
R. P. Laude3
and R. N. Tandang4
1. University Research
Associate and 2.
Professor, Animal
Breeding Division, Institute of Animal Science, College of
Agriculture, University of the Philippines Los Baños, 4031
College, Laguna, Philippines
3.
Professor and
4.
Laboratory Technician,
Genetics and Molecular Biology Division, Institute of
Biological Sciences, College of Arts and Sciences, University
of the Philippines Los Baños, 4031 College, Laguna,
Philippines (Corresponding author: R.P. Laude; e-mail:
rplaude@yahoo.com)
The
industrial revolution, like the automobile, has not rendered
the horse useless, and today this animal is enjoying
unprecedented popularity in different countries, as well as in
the Philippines.
Even in rural areas in the Philippines until now,
horses are still used to transport goods, like coconut and
other agricultural products, from one place to another.
An important primary step toward improvement of a
species is to know the extent of its genetic variation.
Unfortunately, however, such information on native horses in
the country is scarce.
This study aimed at analyzing the genetic variation of
native horses in Laguna using protein and isozyme
markers. With
samples of 100 native horses from three localities of Laguna,
Philippines and based on eight loci, we observed that the
horse population in Alaminos had the highest genetic
variability, followed by that in Nagcarlan and lowest in
Mabitac. We also
observed high genetic relatedness between the horse
populations of Nagcarlan and Mabitac, and Alaminos and
Nagcarlan. On the
other hand, the horse populations of Alaminos and Mabitac had
the lowest genetic relatedness. These indicate that
native horses from Nagcarlan and Mabitac share many genes in
common. The
information obtained in this study can be of great use to
people involved in horse breeding, conservation, feeding,
nutrition, and physiology and proper
management.
Philipp.
Agric. Scientist 87: 14-22
(2004)
Some New and Unusual
Otocepheids from Samar and Mindanao Island, Philippines
(Acari: Oribatida: Otocepheidae)
Leonila A.
Corpuz-Raros
Professor, Department of Entomology, College of
Agriculture, University of the Philippines Los Baños, College,
Laguna 4031, Philippines (Curator, Entomological Museum,
Museum of Natural History, University of the Philippines Los
Baños, College, Laguna 4031, Philippines
Mites are
important components of the soil subsystem where they dominate
other animals in terms of kinds and numbers. Some of these
participate in litter breakdown and spread spores of fungi and
other microorganisms of decay. Others feed on the former
groups of mites and small detritus-feeding insects and
therefore play important roles in the cycling of nutrients in
the soil. The study of soil mites has recently gained impetus
in most parts of the world because of their importance in
decomposition, with practical application in the management of
crop residues and human garbage.
The present study is part of the continuing process of
documenting the diversity of mites in Philippine soils. It
reports the discovery of five unusual species from Mt.
Malindang Range in the province of Misamis Occidental in
Mindanao Island, and from the provinces of Eastern and Western
Samar in Samar Island. Two of these species are so unique that
two new genera have to be erected to accommodate them in the
present
classification of
the family to which they belong, that is, the family
Otocepheidae. As required by the International Code of
Zoological Nomenclature these newly discovered genera and
species are described and characterized, and new names are
given to them before they become available for use by other
zoologists, biologists and other
scientists.
Philipp. Agric. Scientist
87: 23-35 (2004)
Floral Volatiles of
Mangifera indica L.
(cv. Carabao)
Attractive
to Sternochetus
frigidus
(Fabr.) (Coleoptera:
Curculionidae)
L. R. A. de Jesus1,
S. M. F. Calumpang2,
J. R. Medina3
and Kanju Ohsawa4
1.
RONPAKU Fellow, Tokyo
University of Agriculture, Tokyo, Japan; also Senior
Agriculturist, DA-RFU 4, Marauoy, Lipa City 4217, Batangas,
Philippines (corresponding author; e-mail:
louelladejesus@yahoo.com)
2. Behavioral Control,
Genetics and Ecology Laboratory, National Crop Protection
Center, University of the Philippines at Los Baños, College
4031, Laguna, Philippines
3. Department of
Entomology, University of the Philippines at Los Baños,
College 4031, Laguna, Philippines
4. Department of
Bioscience, Faculty of Applied Bioscience, Tokyo University of
Agriculture, Tokyo 156, Japan
The mango pulp weevil,
Sternochetus frigidus (Fabr.), is an important pest in
Palawan that exclusively feeds and develops on fruits of mango
varieties. In
field observations, it has been found that in the absence of
mango fruits, the weevils feed also on the mango panicles
during full bloom stage.
This led us to investigate the chemical composition of
the ‘Carabao’ mango panicle and determine some of the
components that might be attractive to the
weevil.
About 138 compounds constitute the aroma of ‘Carabao’ mango
panicles at full bloom stage. The major components
were the hydrocarbons, alcohols and esters. The minor components
consisted of carboxylic acids, ketones, aldehydes, ether and
amide. We found
that singularly acetic acid and decane at doses equivalent to
10 mango panicles were attractive to the weevil and that the
attractancy response of the weevil was dose dependent. Our findings
established that certain components of the ‘Carabao’ mango
panicles attract the mango pulp weevil. These findings would
be useful in the further development of control measures
against this pest.
Philipp. Agric. Scientist
87: 36-40 (2004)
Research Note: Suppression
of Rhizoctonia solani in Corn by
Hypovirulent Binucleate Rhizoctonia and the
Nature of Protection
Cecilia B. Pascual1*,
Avelino D. Raymundo2
and Mitsuro Hyakumachi3
1. Institute of
Plant Breeding and 2Department
of Plant Pathology,
University of the Philippines Los Baños, College 4031,
Philippines and 3Faculty
of Agriculture, Gifu University, 1-1 Yanagido, Gifu, Japan
501-1193. (*corresponding
author e-mail: cbpascual22@yahoo.com or
cbp@ipb.uplb.edu.ph)
Cereal crops like corn suffer from a destructive
disease called banded leaf and sheath blight (BLSB) caused by
the fungus Rhizoctonia solani. In recent years, much
emphasis has been placed on biological control of plant
pathogens. In this regard, we earlier isolated a strain of a
less virulent type of Rhizoctonia called BNR Rhv7 from a corn
field in Pangasinan which we reported to be able to control
BLSB in corn under laboratory and screenhouse conditions.
In this follow-up study, we tested the effectiveness of
the Rhv7 under field conditions. Corn plants that were grown
in soil infested with the virulent type of R. solani
(AG1-1A) and treated with Rhv7 in rice-rice hull reduced the
severity of the disease in contrast to plants grown in
infested soil with no Rhv7, only rice-rice hull or without any
treatment. There was also lower incidence of the BLSB disease
and delayed start of the disease in corn plants grown in BNR
Rhv7-treated soil. We also observed that Rhv7 protected the
leaf sheaths of corn from formation of lesions caused by
fungal infection by inducing systemic resistance.
Philipp. Agric. Scientist 87: 41-48
(2004)
Indices for Varietal
Identification of Mango (Mangifera indica L.)
Evelyn Mae
Tecson-Mendoza1*,
Felicito M. Rodriguez1,
Perla F. Baldiviano-Josue1
and Leon O. Namuco2
1.
Research Professor,
University Researcher and former University Research
Associate, respectively, Institute of Plant Breeding, College
of Agriculture, University of the Philippines Los Baños,
College, Laguna 4031, Philippines (*Corresponding author;
e-mail: emtm@laguna.net)
2.
Associate Professor,
Department of Horticulture, College of Agriculture, University
of the Philippines Los Baños, College, Laguna 4031,
Philippines
For many
decades, identifying mango varieties at the seedling stage has
been a major problem of the Philippine mango industry. To address this
problem, simple methods were developed to identify four
popular varieties of mango in the Philippines:
Carabao, Katchamita or Indian, Pico and Pahutan.
The first method
consists of observing the color and orientation of one-week-old flushes
of seedlings. The following were observed: light green with
brown tinge of horizontal leaves for Carabao; light brown with
purplish tinge for Katchamita, light green with drooping
leaves for Pahutan, and light brown for Pico. The second
method consists of observing the shape of leaf tips. The leaf
tip of Carabao is described as abrupt acuminate indicating a
rapid sharpening of the tip compared with that of Katchamita,
Pico and Pahutan which is narrow acuminate indicating slow
sharpening of the tip. The third method involves crushing the
mango leaf and smelling the aroma released. The aroma of
crushed leaf is as follows: For Carabao, the aroma is similar to that of
unripe fruit of Carabao variety; for Katchamita, the aroma is
more intense and aromatic and similar to that of unripe Katchamita
mango; for Pahutan, the aroma of crushed leaf is more similar
to that of pili nut than mango; and for Pico, the aroma of
crushed leaf is
similar to that of the Carabao fruit. The fourth method
consists of extracting the phenolic compounds from the leaves
with acidified methanol. The leaf phenolic extract of Pahutan
has the most intense green color while the extracts of Pico,
Carabao and Katchamita have similar yellowish green color.
Further reaction of the extracts with acidified vanillin
differentiated the four varieties: light pink color for
Carabao, pink color for Katchamita, and Pico, and light green
color for Pahutan.
The study shows that the most practical method of mango
varietal identification is by determining the color and
orientation of young
flushes. This can
be used for both seedlings and mature trees. A simple
cost and return analysis shows that use of this technology
would cost only PhP 207.20 per ha. On the other hand, it will
cost a farmer P1,875 for every plant of unwanted variety that is reared to
fruiting stage.
Philipp. Agric. Scientist 87: 49-60
(2004)
Fern
Patch Structure and Species Diversity Along the Altitudinal
Gradient of Mt. Banahaw de
Lucban, Luzon Island, Philippines
M. C. N. Banaticla1
and I. E. Buot, Jr.2
1.
Former Graduate
Student, Institute of Biological Sciences, Graduate School,
University of the Philippines Los Baños, College, Laguna 4031,
Philippines (Corresponding author; e-mail:
MCNBanaticla@hotmail.com); Current address: Genetic Resources
Center, International Rice Research Institute, Los Baños,
Laguna, Philippines
2.
Associate Professor,
Institute of Biological Sciences, University of the
Philippines Los Baños, College, Laguna 4031,
Philippines
Mt. Banahaw
de Lucban is one of the three peaks that form an isolated
mountain mass traversing the provinces of Laguna and Quezon
and forming the southwestern tip of the Sierra Madre mountain
range in the Philippines. The other two are Mt. San Cristobal
and Mt. Banahaw, the central and tallest peak. This Banahaw-San
Cristobal mountain complex is one of the 12 centers of plant
diversity and endemism in the Philippines as recognized by the
Worldwide Fund/International Union for the Conservation of
Nature (WWF/IUCN). However, there is limited literature on the
floristic composition and structure of its plant
communities.
This study determined the species diversity, dominance
and patch
structure of pteridophyte or fern species along the
altitudinal gradient of the study area and determined the
relationship between pteridophyte species diversity and
environmental factors particularly elevation, slope and soil
properties.
A general survey of the study area was conducted to
determine the vegetation patches which are characterized by
plant communities with uniform features and particularly
dominated by fern species. Forty-two (42) fern
patches were sampled using the line intercept method. These
fern patches were considered as sampling sites. Seven of these
sampling sites are in disturbed areas while the remaining 35
are located within the forest
reserve.
Ninety-three species including eight Philippine
endemics representing 47 genera and 24 families were found in
the study area.
Ten species from two genera and two families are fern
allies while the remaining 83 are true ferns. The most
represented families are Polypodiaceae (11 spp.),
Hymenophyllaceae (11 spp.) and Aspleniaceae (9
spp.) while the most represented genera are Asplenium
(9 spp.), Lycopodium (5 spp.) and Selaginella (5
spp.).
Species diversity gradually increased with elevation,
peaking at 814 to 886 meters above sea level where the area is
covered with secondary forest. Based on the result of
stepwise multiple regression analysis, the slope was linearly
related to species diversity. Steeper slopes including ravines
offered more microenvironment for the ecological specialist
species of pteridophytes as shown in their strong positive
relationship. However, climatic and biological factors like
temperature, precipitation , relative humidity and soil
properties can also influence the pteridophyte species
diversity in the study area.
Species cover or abundance was found to have no strong
relationship with altitude. This would depend on the species
and its physical environment. Majority of the
patches sampled was composed of the four height classes
designated in this study, indicating a pterido-flora that is
well-distributed in the forest strata. At least 85 per cent of
the pteridophyte species are preferential or have a narrow
tolerance range and are dependent on the available
microenvironments. The most frequently occurring species are
Selaginella delicatula, Selaginella cumingiana,
Sphaerostephanos hirsutus, Cephalomanes apiifolia, Cyathea
philippinensis and Cyathea
callosa.
Philipp. Agric. Scientist 87: 61-75
(2004)
Review: Comparative
Evaluation of Different Approaches
to
Estimate Aboveground Biomass and Biomass Density
of
Tropical Rainforests in Southeast Asia
Damasa B.
Magcale-Macandog
Assistant Professor, Institute of Biological Sciences,
College of Arts and Sciences, University of the Philippines
Los Baños, College, Laguna 4031, Philippines (e-mail:
macandog@pacific.net.ph)
Estimates of forest biomass are important
for commercial uses such as assessing timberwood and
fuelwood and for
scientific uses such as in studying ecosystem productivity and
energy and nutrient flows. On the other hand, policy-makers
need accurate and precise information on the state, patterns
and rates of change of forest biomass in national development
planning regarding the management and use of forests and
trees. Thus, it is important that the estimates of forest
biomass be accurate and reliable.
This review therefore was done on forest aboveground
biomass data of three countries: the Philippines, Indonesia
and Thailand. It revealed a great variability and problems on
the reliability of the forest aboveground biomass data in
these countries. This study noted the different approaches for
estimating aboveground biomass which include destructive
sampling and allometric regression. Approaches for estimating
biomass density include stem volume, stand table, historic and
geographic information system (GIS) approaches. While destructive
sampling is considered the most direct and accurate approach
in determining individual tree biomass, extrapolation of
biomass density of a unit area or forest stand using
destructive sampling data from a few selected trees or
sampling plots often leads to overestimation of biomass
density.
It was recognized that Biomass Expansion Factor (BEF)
and average diameter are the key factors in the conversion of
volume and stand table data, respectively, to biomass
density. Biomass
estimates using stand table approach are midway between those
estimates resulting from ecological and volume
approaches. GIS
approach permits spatial extrapolation of the local data
estimate biomass density changes as affected by climate,
topography, soil, population pressure, and
land-use.
The author concluded that it is very difficult to make
a direct comparison of aboveground biomass and biomass density
estimates of the different forest types in Southeast Asia due
to lack of common forest type classification as reported in
the different articles reviewed.
Philipp. Agric. Scientist 87: 76-86
(2004)
Production of Biodegradable
Plastic from Local Strains
of Bacillus
megaterium
Gloria Despacio-Reyes1,
Susan M. Mercado2,
Rosario S. So3
and Carmela C. Alviar4
1.
Assistant Professor, University of the Philippines Open
University, College, Los Baños, Laguna 4031, Philippines
(Corresponding author: e-mail:
greyes@upou.org)
2.
Research Assistant
Professor, 3University Researcher, 4
Former University
Research Associate, National Institute of Molecular Biology and Biotechnology
(BIOTECH),
University of the Philippines Los Baños, College,
Laguna 4031, Philippines
Because of the need to protect the environment, global
interest in the development of biodegradable plastics has
increased since the early 1980s. In a previous paper, we
reported the screening and identification of Philippine
strains of Bacillus megaterium which produce
biodegradable plastic. In this study, we sought to identify
the best local agro-industrial waste as medium for growing
B. megaterium and to establish the optimum conditions
for the production of biodegradable
plastic.
Using coconut water, molasses, nata de coco spent
liquor and whey, we found coconut water to be the best medium
on which the B. megaterium strains produce
poly-b-hydroxybutyrate (PHB), a kind of biodegradable plastic.
Strain GR149 was the best strain among those tested. We also
observed that coconut water has to be supplemented with 2.0%
glucose and 0.5% ammonium chloride and pH adjusted to 7.0 for
optimum production of PHB. The optimum fermentation conditions
were also established to be: 28 C, 200 revolutions per minute
(rpm) agitation and 0.5 vvm aeration.
Since PHB is produced inside the cells, we also
optimized the conditions for extracting and separating PHB
from the cells. The process of drying the cells with acetone
followed by alkaline hypochlorite digestion prior to
chloroform extraction gave the best polymer recovery. The PHB
produced had physicochemical properties that are
characteristic of plastics.
Philipp. Agric. Scientist 87: 87-95
(2004)
Development of Membranes
from Bacterial Cellulose (Nata de Coco) for the Separation of
Copper (II) Ions Using Polyelectrolyte-Enhanced
Ultrafiltration
R. DV. Espiritu1,
R. R. Navarro2
and E. J. del Rosario3
1.
Undergraduate (BS Chem.
Engg.) student and 2.
Assistant Professor,
respectively, Department of Chemical Engineering, College of
Engineering and Agro-Industrial Technology, University of the
Philippines Los Baños, 4031 College, Laguna,
Philippines
3.
Professor, Institute of
Chemistry, College of Arts and Sciences, University of the
Philippines Los Baños, 4031 College, Laguna, Philippines
(Corresponding author; e-mail:
ejr@chem.uplb.edu.ph)
Ultrafiltration is a membrane-based process used to
recover valuable substances from agricultural and food
processing streams as well as to remove heavy metals from
industrial wastewater to minimize pollution effects. In this
study, we report the development of cellulose acetate
membranes from nata de coco (a material produced by the
bacterium Acetobacter xylinum) and its use in the
separation of cupric ions in the presence of a
polyelectrolyte. The polyelectrolyte, such as
polyethyleneimine (PEI) or carboxymethylcellulose (CMC), will
complex with cupric ions which will result in the latter’s
retention on the cellulose acetate membrane. The
physicochemical characteristics of the nata de
coco-derived cellulose acetate (CA) membrane were analyzed
and found to be appropriate for ultrafiltration. The authors
successfully separated cupric ions using either
polyelectrolyte on the CA membrane 79 to 100%. The nata de
coco CA membrane was also 70% as effective as the commercial
type of membrane. It is recommended that pilot-scale
experimentation be done to optimize the process and to
properly evaluate its cost effectiveness.
Philipp. Agric. Scientist 87: 96-100
(2004)
Research Note: Biological
Activity of Moringa oleifera Lam. (Malunggay) Crude
Extract
Katherine B. Saravillo1
and Annabelle A. Herrera2
1.
Former undergraduate
student of the Institute of Biology, College of Science,
University of the Philippines
Diliman
2.
Professor, Institute of
Biology, College of Science, University of the Philippines
Diliman, Quezon City 1101, Philippines (corresponding author;
e-mail: herrera@edsamail.com.ph)
Horseradish tree (Moringa oleifera L.), locally
known as malunggay, is a popular plant used in folk medicine.
Its seeds have been found to have antimicrobial, antimutagenic
and antitumor activities. Because of its varied uses, its
possible hazards and true medicinal value must be
investigated. In this study, we determined if the methanolic
crude extract of malunggay seeds can promote blood vessel
formation and counteract gross malformation using duck embryo
as experimental animal.
Our results showed that the crude extract has antitumor
activity as it was able to counteract a chemical, retinoic
acid, which causes abnormalities in the duck embryo. It was
also found to exhibit antiangiogenic activity or a property to
inhibit blood vessel formation. However, malunggay crude
extract was also observed to delay feather formation of the
duck embryo. These results indicate that to be able to utilize
properly the antitumor activity of malunggay, its active
principle must first be isolated, purified and fully
characterized since the crude extract contains substances
which may have adverse effects on human
health.
Philipp. Agric. Scientist 87: 101-109
(2004)
Development of Food Products
from Dephytinized and Stabilized Rice Bran
Wilma A. Hurtada1
and Maria Angeline B. Cosico2
1.
Associate
Professor, Institute of Human Nutrition and Food, College of
Human Ecology, University of the Philippines Los Baños,
College, Laguna 4031, Philippines (Corresponding author;
e-mail: wilmahurtada@yahoo.com)
2.
University
Research Associate, Department of Soil Science, University of
the Philippines Los Baños, College, Laguna 4031,
Philippines
Rice bran is an agricultural waste or by-product which
may have a potential in the food industry because of its
nutritional value. It is rich in vitamins and minerals and is
an excellent source of dietary fiber. However, the use of rice
bran in food is limited by the rapid development of rancidity
in bran after milling. Rice bran also contains a high level of
phytic acid which is an anti-nutrient because it complexes
with minerals. This study addresses these limitations of using
rice bran in food.
Our study established the conditions needed to
effectively remove the phytic acid (dephytinization) from rice
bran and stabilize the bran so that it will not turn rancid
with minimal losses in nutrients and dietary fiber. We found
that soaking the rice bran in water under ordinary conditions
for 8 hours reduced phytic acid by 72% with little losses in
minerals and dietary fiber. The bran was stabilized by
steaming followed by drying. This can prevent
development of rancidity and microbial growth even up to 7
weeks under ordinary conditions of
storage.
We successfully incorporated about 25% rice bran in
baked products like cookies, biscuits and brownies which are
acceptable in terms of color, flavor, aroma and texture. Rice
bran-containing baked food products are rich in crude and
dietary fiber, fat, phosphorus, iron, thiamin, riboflavin and
niacin. They are also cheaper than their counterpart
full-wheat food products.
Philipp. Agric. Scientist 87: 110-118
(2004)
Rediscovery of
Musa splendida A.
Chevalier and
Description of Two New Species, Musa viridis and Musa
lutea
Ramon V. Valmayor1*,
Le Dinh Danh2
and Markku Häkkinen3
1.
President, Philippine
Agriculture and Resources Research Foundation, Inc. (PARRFI),
c/o PCARRD, Paseo de Valmayor, 4030 Los Baños, Laguna,
Philippines (e-mail:
parrfioffice@pacific.net.ph); also former Regional
Coordinator of Asia and the Pacific Network (ASPNET),
International Network for the Improvement of Banana and
Plantain (INIBAP).
2. Director, Phu Ho Fruit
Research Center, Phu Ninh, Phu Tho, Vietnam; Curator, National
Banana Germplasm Collection, and Leader, Vietnam Banana
Collection, Characterization and Conservation Project. Fax No.: (84)
0210-865-278
3.
Associate Researcher at
the Helsinki University Botanic Garden. P.O. Box 44, Fin-00014
University of Helsinki, Finland (e-mail:
markku.hakkinen@kymp.net)
*Corresponding author
Musa
splendida Chevalier (M.
splendida) is a very rare species of wild banana, which is
believed to be nearing extinction. Due to its rarity,
some researchers even doubted its existence even if it is
described in some references. Several banana
prospection missions and explorations had also been done but
M. splendida was not included. But due to reports of
elderly people in Vietnam that Choui Gai, as what they call
it, really exists, exploration still continued. Dr. Inge van den
Bergh, International Network for the Improvement of Banana and
Plantain (INIBAP) Associate Expert at the Vietnam Agricultural
Science Institute, surveyed the original abode of this wild
banana. There, he
was able to discover large populations of it in the Red River
Valley, near Lao Cai, Vietnam. It was then added to
the wild and cultivated banana specimens of the Phu Ho Musa
germplasm collection.
Moreover, due to insufficient description and data
about M. splendida, it has been closely associated with
or even mistaken for other species. In South China, for
example, there were resemblances between Musa
paracoccinea and M. splendida. But then, researchers
were not surprised because the latter is indigenous to the
Yunnan province of South China and M. splendida is a
native of Lao Cai in northern Vietnam where the only
separation was the Red River. Because this species
had been rediscovered in a living state, its validity has been
established.
Musa viridis and Musa lutea are two new
types of the Musa species. These are
differentiated from the common indigenous Musa species
of Vietnam and South China by their erect inflorescences and
fruit bunches.
Species from the said places have pendulous or
subhorizontal inflorescences and fruit bunches. It can also be
distinguished from the recently discovered M. splendida
and the popular M. laterita because the latter two
species are rhizomatous or have a lot of
roots.
Differentiating M. viridis and M. lutea
from each other is easy by simply looking at the color of
their immature fruits.
M. viridis is silvery green while M.
lutea is yellow.
These colors, silvery green and yellow, are
viridis and lutea in Latin where they got their
names. Another
characteristic to tell them apart are the colors of the male
bud. M.
viridis is pinkish-lilac while M. lutea is
orange-red.
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