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Validation of Newly Designed SSR Markers for Eight Rice (Oryza sativa L.) Genotypes with Variable Heat Tolerance Responses Based on Agromorphic Data and Pollen Fertility Analysis [RESEARCH NOTE]
Get PDFRice is one of the most valuable staple food crops in the world. However, several challenges greatly affect production, one of which is the threat imposed by heat stress. To address this, researchers are developing varieties that are heat stress tolerant with genetic markers aid. In this study, eight rice genotypes, namely Dular, Nagina 22, NSIC Rc 222, Milyang 23, EL15, EL92, EL85, and IR52 were observed for agromorphic data, which included plant height, panicle length, filled and unfilled grains, and grain yield. Flower samples were collected to determine the effect of heat stress on pollen fertility. Molecular markers were designed via in silico analysis based on the nine QTL regions distributed among five chromosomes (1, 3, 4, 5, and 10). Out of the 90 newly developed markers, Markers 3066 and 2503 showed good potential as informative markers among heat tolerance classification. Results showed the genotype-specific responses of varieties during heat stress and non-heat stress conditions. EL15 had the best agromorphic performance and appeared to be the best elite line. Identification of gene-specific SSR markers has proven to be effective in understanding heat tolerance for future marker-assisted selection
Evaluation of prebiotic potential of sweet potato (Ipomea batatas L.) through in vitro assay
No full textPrebiotics are non-digestable carbohydrates that enhance the growth of beneficial bacteria in the gastrointestinal tract. This study evaluated the prebiotics potential of two varieties of sweet potatoes sold at the local market. Basal medium devoid of carbon source was supplemented with the sweet potato flour and the growth of selected Lactobacillus species and E. coli were evaluated. Prebiotic scores were evaluated based on the growth of these two species of bacteria known to be present in the agrointestinal tract. Higher change in cell density of the Lactobacillus species was observed compared to Escherichia coli indicating that the sweet potato flour added into the culture medium favored the growth of the Lactobacillus compared to that of E. coli. The prebiotic scores obtained in this study showed comparable activity to a commercial prebiotic and a natural source of prebiotic. Resistant starch and dietary fiber of the sweet potato flours were analyzed and correlated to their prebiotic potential
Assessment of major diseases in commercial sweet sorghum varieties and development of management strategies
No full textFive commercial varieties/lines of sweet sorghum with good agronomic traits and sugar yield namely: ICSV700, ICSV93046, SPV422, NTJ2, and ICSR93034 were screened for resistance to bacterial stalk rot in the greenhouse of the National Crop Protection Cluster and under field conditions at the Central Experiment Station of UPLB [University of the Philippines Los Baños]. The bacterial isolates used in the greenhouse screening were highly virulent as shown in potato rot test and in pathogenicity test using one-month old sweet sorghum plant. Among the three inoculation methods tested, stem wounding and dropping of 0.1 ml inoculum suspension gave consistent stalk rot infection. Drenching of 10 ml homogenized bacterial suspension at the base of seedlings (without wounding) contained in plastic seedling bags and dropping of 1.0 ml bacterial suspension into the whorl of sweet sorghum resulted to poor stalk infection. Field evaluation studies showed low incidence of bacterial stalk rot during the dry season trial. In the wet season and ratoon crop trials, ICSV 700 and ICSV 93046 were resistant. Field evaluation of fungicides for its efficacy manage major fungal diseases of sweet sorghum (Sorghum bicolor (L.) Moench) was conducted for three trials (dry and wet season seed crop; and a ratoon crop) at the UPLB Central Experiment Station from November 2009 to February 2011. A sweet sorghum commercial variety NTJ2 was used in the trial. Seed-borne fungi from sweet sorghum were detected in disinfected and non-disinfected seeds. Nine fungal species distributed among Aspergillus, Penicillium, Curvularia, Fusarium, Bipolaris, Rhizopus, and Chaetomium were recorded. Sterile mycelia and four interesting coelomycetes seeds, species of Aspergillus are the most dominant followed by species of Curvularia, Penicillium and sterile mycelia. On the other hand, disinfected seeds revealed high presence of species of Curvularia followed by sterile mycelia, Fusarium, Aspergillus, Penicillium, coelomycete 2, coelomycete 1, Bipolaris and coelmycete 3
Utilization of saba (Musa saba [Musa acuminata x Musa balbasiana]) flour and camote (Ipomea batatas) flour in polvoron formulations
No full textIn order to increase the usefulness and efficiency of saba flour and camote flour in food systems, these were used in the formulation of polvoron. Five treatments for each were utilized, varying the proportions of saba flour (or camote) with that of all-purpose flour. The polvoron formulations were subjected to sensory analysis. For both the saba and camote, Treatment C (50:50) showed least significant difference from Treatment A (100% All-purpose flour). These treatments were then subjected to proximate composition analysis. For the saba formulation, Treatments A and C contained almost the same amount of moisture, crude fat, and crude fiber but differ significantly in ash, crude protein, and total carbohydrates. The camote Treatments A and C contained almost the same amount of crude fat, protein and total carbohydrates but differed significantly in moisture, crude fat, and crude fiber ash. Texture analysis was also performed to determine relative breaking strengths of the polvoron formulations. Treatment C for the saba formulation and Treatment B (25 camote: 75 all-purpose flour) for the camote formulation have the highest breaking strengths next to Treatments A. Saba flour can be substituted to all-purpose flour upto 50% while camote flour can substitute all-purpose flour at 52-50%
Analysis of the environmental impacts of invasive exotic forest tree species: the case of paper mulberry (Broussonetia papyrifera) (L.) L\u27her. Ex Vent.
No full textSaliw ng Liliw: A Study on the Climate-Resilient Vegetable Farmers of Liliw, Laguna
Get PDFhttps://www.ukdr.uplb.edu.ph/cspps_policy_brief/1005/thumbnail.jp
Allelopathy of Faba Bean Cover Crop to Durum Wheat Under a Semi-Arid Environment
Get PDFProblems facing farmers practicing conservation agriculture in the semi-arid zone of Tunisia include appropriate cover crop selection, management of allelopathic effects affecting subsequent crop performance, and influence of seasonal variation on allelopathy expression. Allelopathy expressed by faba bean (Vicia faba L.) toward durum wheat [Triticum turgidum ssp. durum (Desf.) Husn.] was studied using bioassays during three growing seasons. The role of phenols in the expression of such potential was also investigated. Analyses of plant samples at three phenological stages (flowering, fruiting, senescence) revealed that leaves were most inhibitory. Allelopathic potential differed among plant components and phenological stages, with the greatest inhibitory effects occurring at senescence (49%). Inhibition varied across growing seasons, suggesting an environmental impact linked to inter-monthly water-balance variability. Inter-monthly rainfall appeared to be negatively related to the intensity of the allelopathic potential. The total phenolic content varied among plant components, phenological stages, and growing seasons, and the results implied that climatic variation may impact phenol accumulation in plant tissues. Total phenolics content of roots and stems significantly (p = 0.003 and 0.03, respectively) contributed to faba bean allelopathy. Use of faba bean as a cover crop preceding durum wheat carries a risk of allelopathic effects, which could negatively impact grain yield. Understanding the allelopathy of faba bean as a cover crop is critical for efficient management of residues under conservation agriculture
Development and Characterization of Rice Lines Carrying both Sub1 and Anaerobic Germination Tolerance: SUB1A does not Inhibit AG [RESEARCH NOTE]
Get PDFAccelerated coleoptile elongation in flooded soils allowed seedling shoots to reach the water surface to maintain gas exchange and CO2 fixation. Rice genotypes with tolerance of flooding during germination (anaerobic germination, AG) exhibited fast coleoptile elongation as an escape mechanism. On the other hand, tolerance of complete submergence during the vegetative stage, conferred by SUB1A, involved growth retardation to conserve energy for maintenance metabolism, with resumption of growth upon de-submergence. Combining genes controlling flood tolerance at these two stages with contrasting mechanisms was necessary in flood-prone areas for protection during germination under direct seeding and during vegetative stage. Breeding lines combining AG + Sub1 were used to determine the timing of the expression of SUB1A and elucidate its impact when combined with tolerance of flooding during seed germination and to evaluate seedling performance under complete submergence. Time-points for SUB1A expression in IR64-Sub1 and AG + Sub1 lines germinated under hypoxia or submerged for 30 h at vegetative stage showed that during flooding treatment, SUB1A and SUB1C expression was inhibited in young seedlings (\u3c 6 d old) in IR64-Sub1 and at 2 and 4 d of seedling growth under hypoxia in AG + Sub1 materials. SUB1A was weakly expressed in AG + Sub1 starting at seedling age of 6 d following 1 d of complete submergence, indicating that expression of SUB1A may be stage-specific. Physiological tests showed higher percentage of survival of AG + Sub1 lines under hypoxia, comparable to that of AG tolerant check and significantly different from intolerant check IR42, indicating that the presence of SUB1A does not affect tolerance of flooding during germination. When seedlings were completely submerged, Sub1 expression was not inhibited by the presence of AG and tolerant genotypes showed suppressed elongation that was significantly different from intolerant check IR42. Despite their contrasting mechanisms of tolerance, combining AG with Sub1 provides multiple flooding tolerance from early crop establishment using direct seeding through to the vegetative stages
Organizational resilience of volunteer organizations during the Covid-19 pandemic : the case of Rotary Club of Los Baños
No full textAn assessment of the complex operation of blended learning in teaching English in a public high school in Los Baños, Laguna
No full textBlended learning was one of the learning modalities utilized in the country particularly when the COVID-19 pandemic took place. Many studies have been conducted to understand and prove its effectiveness however these studies failed to look at it as a modality that consists of many elements that are connected and must collaborate to improve its operation and effectively address its challenges. Hence, the study aimed to explore the experiences of groups of stakeholders involved in blended learning on how they worked together to teach English as well as to identify the challenges they have encountered. A key informant interview and focus group discussions were employed as data-gathering methods while thematic analysis was used to properly organize and discuss the blended learning experiences of the stakeholders. The study found that there are factors that have fostered stakeholder collaboration and proved that they have encountered challenges. While some efforts were made to address these challenges, collaborative solutions were not implemented uniformly. Nonetheless, the Department of Education was also acknowledged to have a critical role in stakeholder collaboration