Genetic variation and interrelationships of acid detergent fiber, neutral detergent fiber, hemicellulose, crude protein and in vitro dry matter digestibility in tall fescue (Festuca arundinacea Schreb)

Six parent clones and their 15 single-crosses of tall fescue (Festuca arundinaceae, Schreb) were row-planted in Corvallis, Oregon, row and sward-planted in Columbia, Missouri, and evaluated for genetic variability, genotyp-eenvironment interactions and interrelationships in acid detergent fiber (ADF), neutral detergent fiber (NDF), hemicellulose (HCL), crude protein (CP) and in vitro dry matter digestibility (IVDMD) for each harvest in 1977 and 1978. Analyses revealed that general combining ability or additive genetic effects predominated for all the measured characteristics in the tall fescue diallel cross population. Of the genotype-environment interactions, only general combining ability x harvest interaction effects were significant enough to warrant consideration. The results also suggest that general combining ability of the parents rather than actual parental performance is a better predictor of hybrid progeny performance for all the characteristics. Parent-progeny regressions reveal that ADF is a more transmissible trait than NDF, IVDMD, HCL, or CP. ADF and NDF were highly and significantly correlated to IVDMD while HCL and CP were poorly correlated to IVDMD. It is suggested that the results obtained can have wider applicability to other tall fescue growing areas and populations. The results indicate that a selection program based on progeny testing for general combining ability for low ADF under row-planted conditions in one location for all harvest seasons over one or two years would efficiently and conveniently result in a rapid indirect selection improvement for digestibility in tall fescue

Diversity and ecological guild analysis of the oil palm fungal microbiome across root, rhizosphere, and soil compartments

The rhizosphere microbiome is a major determinant of plant health, which can interact with the host directly and indirectly to promote or suppress productivity. Oil palm is one of the world’s most important crops, constituting over a third of global vegetable oil production. Currently there is little understanding of the oil palm microbiome and its contribution to plant health and productivity, with existing knowledge based almost entirely on culture dependent studies. We investigated the diversity and composition of the oil palm fungal microbiome in the bulk soil, rhizosphere soil, and roots of 2-, 18-, and 35-year old plantations in Selangor, Malaysia. The fungal community showed substantial variation between the plantations, accounting for 19.7% of community composition, with compartment (root, rhizosphere soil, and bulk soil), and soil properties (pH, C, N, and P) contributing 6.5 and 7.2% of community variation, respectively. Rhizosphere soil and roots supported distinct communities compared to the bulk soil, with significant enrichment of Agaricomycetes, Glomeromycetes, and Lecanoromycetes in roots. Several putative plant pathogens were abundant in roots in all the plantations, including taxa related to Prospodicola mexicana and Pleurostoma sp. The mycorrhizal status and dependency of oil palm has yet to be established, and using 18S rRNA primers we found considerable between-site variation in Glomeromycotinian community composition, accounting for 31.2% of variation. There was evidence for the selection of Glomeromycotinian communities in oil palm roots in the older plantations but compartment had a weak effect on community composition, accounting for 3.9% of variation, while soil variables accounted for 9% of community variation. While diverse Mucoromycotinian fungi were detected, they showed very low abundance and diversity within roots compared to bulk soil, and were not closely related to taxa which have been linked to fine root endophyte mycorrhizal morphology. Many of the fungal sequences showed low similarity to established genera, indicating the presence of substantial novel diversity with significance for plant health within the oil palm microbiome

Pyrolysis of Napier grass in a fixed bed reactor:effect of operating conditions on product yields and characteristic

This study presents a report on pyrolysis of Napier grass stem in a fixed bed reactor. The effects of nitrogen flow (20 to 60 mL/min), and reaction temperature (450 to 650 degrees C) were investigated. Increasing the nitrogen flow from 20 to 30 mL/min increased the bio-oil yield and decreased both bio-char and non-condensable gas. 30 mL/min nitrogen flow resulted in optimum bio-oil yield and was used in the subsequent experiments. Reaction temperatures between 450 and 600 degrees C increased the bio-oil yield, with maximum yield of 32.26 wt% at 600 degrees C and a decrease in the corresponding bio-char and non-condensable gas. At 650 degrees C, reductions in the bio-oil and bio-char yields were recorded while the non-condensable gas increased. Water content of the bio-oil decreased with increasing reaction temperature, while density and viscosity increased. The observed pH and higher heating values were between 2.43 to 2.97, and 25.25 to 28.88 MJ/kg, respectively. GC-MS analysis revealed that the oil was made up of highly oxygenated compounds and requires upgrading. The bio-char and non-condensable gas were characterized, and the effect of reaction temperature on the properties was evaluated. Napier grass represents a good source of renewable energy when all pyrolysis products are efficiently utilized