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Biology of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) on Rice and Different Corn Varieties
Get PDFRice and corn are one of the most important crops in the Philippines. Several insect pests contribute to the losses and low yield of these crops. The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), was recently reported to cause economic damage to corn. Also, this insect consists of two genetically differentiated strains namely, the corn strain and the rice strain. This study was conducted in a laboratory conditions to evaluate the biological parameters of FAW on rice and corn varieties. Newly hatched larvae were fed such as the open pollinated variety (OPV), traditional variety, Macho F1 (hybrid), NK 6410 (genetically modified organism), and rice variety, RC 226. Duration of larva, prepupal, pupal, and larva-adult period, pre-oviposition, oviposition, and post-oviposition period, number of egg mass, fecundity, sex ratio, and survivability of larva to adult of different crops were evaluated. The results showed that the duration of development from egg to adult in Macho F1 and NK 6410 with an average duration of 24.58 and 24.66 d was significantly shorter than OPV, traditional variety, and rice variety, RC 226. The number of eggs laid by females reared on Macho F1, NK 6410, and OPV, with a mean of 1125.60, 1176.80, and 1049.40, respectively, were significantly greater than the traditional variety, tinigib, and rice RC 226. Different corn varieties and rice did not affect the male and female ratio, longevity, and survivability. The results of this study will provide insights into formulating management strategies for fall armyworm
Incidence, distribution, and genetic diversity of ‘Candidatus Phytoplasma luffae’-related strain (16SrVIII) associated with the cassava witches\u27 broom (CWB) disease in the Philippines
No full textCassava (Manihot esculenta Crantz) is widely grown in the Philippines mainly for human consumption, animal feed, and industrial purposes. However, the cassava industry is recently challenged by the cassava witches\u27 broom (CWB) disease which is known to be caused by phytoplasmas. The extent of the disease and the causal phytoplasma strain in the country are not known until this study. Surveys in major cassava areas in the Philippines conducted from 2017 to 2019 revealed that CWB is present in 13 out of 19 provinces assessed in this study, with symptoms ranging from leaf proliferation, little leaf, shortened internodes, stunted growth, discoloration of the vascular system, and small tubers. Molecular detection (through nested PCR) and sequence analysis of phytoplasma 16S ribosomal RNA gene from CWB-infected plants showed high genetic similarity of \u3e98.65% to Candidatus Phytoplasma luffae 16SrVIII. In addition, the 18 phytoplasma isolates from five provinces successfully grouped to Ca. Phytoplasma luffae 16SrVIII clade in the constructed phylogenetic tree. Analysis on the genetic diversity and structure of Ca. Phytoplasma luffae 16SrVIII sequences from cassava and other host plant species revealed low genetic diversity indices and a rudimentary genetic structure with high haplotype diversity. Meanwhile, neutrality tests showed evidence of recent population expansion in Ca. Phytoplasma luffae 16SrVIII. This is the first study to identify ‘Ca. Phytoplasma luffae’-related strain (16SrVIII) as the causal pathogen of CWB in the Philippines. The information generated in this study can help in better understanding the etiology of the disease and in formulating proper and effective strategies to detect and manage the disease in the Philippines
A study on the effect of various culture media on the growth development of Phaleonopsis grandiflora Reich. f. ovules
No full textOvules of Phalaenopsis grandiflora Reichb. f. were excise at the early-embryo and multicellular embryo stage and were cultured on five media-basal Vacin and Went\u27s solution, Vacin and Went\u27s solution plus 25 per cent coconut water, Murashige and Skoog\u27s solution, Knudson\u27s C and Tsuchhiya\u27s medium. Relatively earlier greening was observed in multicellular embryo cultures. Murashige and skoog\u27s medium best enhanced greening and subsequent seedling growth. The addition of coconut water at 25 per cent (by volume) to basal Vacin and Went\u27s solution enhanced greening and multicellular embryos, slighly inhibited seedling growth of early-embryo cultures and seemed to simulate seedling growth of multicellular embryo cultures
Reproduction, Early Development, and Larval Rearing of the Climbing Perch Anabas testudineus (Teleostei: Anabantidae) in Captivity
Get PDFInduced spawning, early development, and larval rearing of the climbing perch Anabas testudineus were examined under captive conditions. Five female climbing perch [125.33 ± 3.27 mm SL; 70.67 ± 5.59 g BW] were paired with apparently mature males (108.50 ± 3.97 mm SL; 39.27 ± 4.70 g BW) and induced to spawn with 5,000 IU human chorionic gonadotropin (hCG) + 0.5 mL Ovaprim kg BW-1. All hCG + Ovaprim-injected fish spawned 9 – 11 h after hormone administration but saline-injected fish (control group) failed to spawn. Mean egg production per female, fertilization and hatching rates, and larval production per female were 7,667 ± 1,313, 98.11 ± 1.63, 61.01 ± 19.92, and 4,435 ± 1,041 %, respectively. Fertilized eggs (1.52 – 1.96 mm in dia) were almost spherical, non-adhesive, transparent, and buoyant due to a large, single oil globule (515 ± 33 μm in dia). First cleavage appeared 30 min post-fertilization (MPF) and egg development lasted for 20 – 24 h post-fertilization (HPF) (29°C). Newly hatched climbing perch larvae [1.73 ± 0.08 mm in total length (TL)] with yolk volume (YV) and oil globule volume (OGV) of 0.545 ± 0.104 and 0.072 ± 0.013 mm3, respectively, had no pigmented eyes or functional mouth parts and digestive tract, and immobile with the yolk sac pointed upward. Eyes became pigmented and both mouth and anus opened in 1 d old larvae (2.09 ± 0.04 mm TL) in preparation for exogenous feeding. Except for body depth (BD) and pre-anal length (PAL), a general increase in TL (1.73 – 3.72 mm), eye diameter (ED) (0.164 – 0.378 mm), head length (HL) (0.205 – 0.923 mm), and mouth gape (MG) size (0.308 – 0.552 mm) was observed, coinciding with yolk resorption in 7 d post-hatched larvae. Climbing perch larvae were reared at 4 stocking densities (25, 50, 75, 100 larvae L-1) and fed solely on live food (Brachionus rotundiformis from 2 – 12 d and Artemia nauplii from 13 – 40 d) or co-fed live food and microparticulate diet (MPD) (Artemia nauplii from 2 – 15 d and Artemia + MPD from 16 – 40 d). Mean survival rates at lower densities (25 – 50 larvae L-1) were significantly higher than those reared at 75 and 100 larvae L-1 (P \u3c 0.05). Furthermore, climbing perch larvae co-fed Artemia nauplii and MPD showed better survival (28.67 – 81.00%) than those fed solely on live food (24.88 – 64.00%). However, at the end of the 40 d trial period, growth parameters did not vary significantly among densities (P \u3e 0.05), except for the condition factor in larvae co-fed Artemia nauplii and MPD. Taken together, results demonstrate the effectiveness of hCG + Ovaprim for captive breeding and observations on the early development of climbing perch, and the feasibility of rearing the larvae at 25 – 50 L-1 on a combination of Artemia nauplii and MPD under laboratory conditions
Dry Matter Production of Two Rice Cultivars with Contrasting Root Plasticity Expression Under Different Topographic Conditions Subjected to Soil Moisture Fluctuation
Get PDFIn rainfed lowland rice fields characterized by sloping terrains and the presence of a hardpan in a flat topography, plants are often exposed to soil moisture fluctuation (SMF) stress due to erratic rainfall patterns. Root plasticity is one of the key traits that play important roles in plant adaptation under such conditions. In this study, two contrasting genotypes, KDML105 and IRAT109, were examined to quantify the expression of plasticity in root branching at different positions in the toposequence (TP) and in a flat topography with a hardpan, both without a groundwater table, and subjected to SMF. Results showed that KDML105 exhibited improved adaptation to SMF conditions due to its greater root system because of the promoted nodal root production and development of lateral roots in the upper soil layer (0 – 20 cm soil depth) along the TP and above the hardpan in a flat topography, which led to the maintenance of its stomatal conductance and dry matter production. IRAT109, on the other hand, did not express root plasticity in deep-rooting due to the absence of groundwater table, particularly in the upper TP, as well as branching ability above the hardpan in a flat topography, which resulted in less water uptake and reduced dry matter production under SMF. Overall, the results indicated that root plasticity in the upper soil layer could be an important trait for the adaptation of rice, both in a sloping TP without a hardpan or in a flat topography with a hardpan, experiencing SMF
Digestible and Metabolizable Energy in Ground Yellow Corn, Rice Bran, and Copra Meal Fed to 10 to 15 kg Philippine Native Pigs (Benguet Strain)
Get PDFThe experiment was conducted to determine the digestible energy (DE), metabolizable energy (ME), and apparent total tract digestibility (ATTD) of gross energy in ground yellow corn, rice bran, and copra meal when fed to Philippine native pigs. Nine barrows with an average initial bodyweight of 10 kg and ages ranging from 60 to 75 d old were housed individually in metabolism crates and randomly allotted to a triplicated incomplete 3 × 2 Latin square design with three diets and two periods. A corn-based diet containing 94.89% yellow corn and two diets containing 66.42% yellow corn and 30% rice bran or copra meal were fed to the native pigs for 10 d, which included a 5 d adaptation period and a 5 d collection period. The DE and ME in rice bran and copra meal were calculated using the substitution procedure with yellow corn as the basal ingredient. On a dry matter basis, ground yellow corn contained 3445 DE and 3314 ME kcal/kg, with 75.45% ATTD of gross energy (GE). Rice bran had 4137 DE and 4034 ME kcal/kg with 87.02% ATTD of GE, whereas copra meal contained 2914 DE and 2841 ME kcal/kg, with 64.72% ATTD of GE. These values are important in the establishment of feeding standards for the Philippine native pigs
Alternate Day Feeding as a Cost-effective Strategy for Tank Culture of the Pacific Shortfin Eel Anguilla bicolor pacifica
Get PDFThere is a growing interest in the aquaculture of tropical anguillid eels as an export commodity. However, studies on feeding strategies, and the present demand to reduce feed costs need to be addressed to ensure the economic viability of eel farming. In this study, the effects of daily (DF) and alternate day (ADF) feeding on growth, feed utilization, body composition, blood chemistry, liver and intestinal morphology, and economic viability in the Pacific shortfin eel Anguilla bicolor pacifica were examined. Each feeding group of 30 elvers (166.25 ± 16.23 g mean initial wt) were randomly stocked in triplicate 4 m3 outdoor concrete tanks. These were fed for 155 d with formulated eel powder diet (49.77% crude protein; 10.21% crude lipid) made into a paste. Growth and survival were not significantly different between the two feeding groups. However, feed efficiency was improved in the ADF group, with significantly higher protein efficiency ratio (0.63) than in the DF group (0.39). Feed conversion ratio (FCR) was lower in ADF (3.85) than in the DF group (6.44), resulting in a 40% reduction in total feed consumption. Biometric indices, body proximate composition, and blood chemistry were not significantly affected. Likewise, liver and intestinal morphology showed no apparent alterations between groups. Partial costs-and-returns analysis showed that ADF yielded higher net profit and profit index. These results suggest that feeding on alternate days promote compensatory growth, better feed utilization, and normal physiological condition of A. bicolor pacifica, and reduce feed cost in the rearing process. Therefore, alternate day feeding should be promoted as a sound feed management strategy in the tank culture of tropical anguillid eels
Effects of Polishing and Cooking on the Phytochemical Properties and Antioxidant Activities of Selected Philippine Rice Cultivars [RESEARCH NOTE]
Get PDFThis paper evaluated the effects of different polishing times and regular cooking on the phytochemical properties and antioxidant activities of black rice Brillante, red rice Minaangan, and white rice NSIC Rc 160. Rice samples were polished for 0, 15, 30, and 45 s, and were cooked using their optimum cooking water ratio. The samples were then characterized for their phytochemical properties [total anthocyanin content (TAC), total phenolic content (TPC), and total flavonoid content (TFC)] and antioxidant activities [DPPH-radical scavenging activity (DPPH-RSA) and ferric reducing antioxidant power (FRAP)]. Pearson’s correlation analysis (PCA) was employed to determine the strength of the linear relationship between the polishing times and different parameters tested. Results showed that the pigmented rice samples had significantly higher phytochemical properties and antioxidant activities than the white rice sample. Polishing of rice samples considerably reduced their TAC (4.8% to 52.7%), TPC (13.0% to 65.2%), TFC (11.2% to 61.5%), DPPH-RSA (35.0% to 79.9%), and FRAP (11.8% to 68.5%). Cooking also decreased their TAC (24.1% to 92.6%), TPC (14.3% to 78.0%), TFC (14.4% to 74.2%), DPPH-RSA (38.9% to 84.6%), and FRAP (37.0% to 92.8%). Moreover, PCA showed that the polishing time had a strong to very strong negative correlation with phytochemical properties (-0.8809 to -0.9846) and antioxidant activities (-0.8106 to -0.9763). This study concluded that the polishing and cooking significantly affected the phytochemical content and antioxidant activities of white and pigmented rice cultivars. The information generated can be used as a basis for selecting suitable processes to better preserve the antioxidants of pigmented rice
Assessment Of lacatan banana Musa acuminata (AA Group) waste-loss in Santa Ana public market, Manila, Philippines
No full textFood waste has been a global and national problem in the Philippines that occurs at any given time in the retail or household level. Especially in a pandemic, the disruption of the economy would negatively affect the food accessibility and security of people to major food commodities such as Lacatan Banana (Musa acuminata – AA Group). The study aimed to evaluate the extent of the quantity, cost, and nutritional value lost from wasted Lacatan Banana in Santa Ana, Manila Public Market to assist the retailers in assessing efficient measures to reduce or use the food waste in the area and promote sustainability. A qualitative research design was used to obtain the details on the banana wasted and the drivers of fruit wastage in a public market. Data were gathered through key informant interviews, direct observations, and document reviews. Results showed that approximately 1 – 4 kg were lost per month. It was calculated that this was equivalent to a cost of PHP 150 – 350 per month from Lacatan Banana wastes where at least 1 – 8 people could have utilized its nutritional benefits for fiber, potassium, magnesium, vitamin c, and kilocalories. However, findings showed that there were no problems for the waste management of the public market. The participants were aware of the concept of food waste wherein retailers opted to donate the overripened banana or cook banana cakes. Overall, the participants’ wastage system and its use of resources promoted efficiency and sustainability that may be used as a framework for future research