Dry Biomass Percentage Research Articles

Yield of ‘Gigante’ cactus pear cultivated under biofertilizer doses and application intervals

ABSTRACT Due to the water restriction, associated with the high cost of fertilizers, and the need to produce forage in the semi-arid regions, studies using biofertilizers in cactus pear production tend to become impactful. The aim of this study was to evaluate the morphometric characteristics and yield of ‘Gigante’ cactus pear cultivated under doses and application intervals of bovine manure biofertilizer. The experimental design was in randomized blocks, in a 2 × 5 factorial scheme, with two biofertilizer application intervals (14 and 21 days) and five biofertilizer doses (0, 15, 30, 45 and 60 m3 ha-1). Three replicates were used, totaling 30 experimental units. The following variables were evaluated: plant height, number of cladodes, cladode length, cladode width and cladode area index, dry biomass percentage, and green and dry biomass yields. The use of 60 m3 ha-1 of liquid cattle manure biofertilizer increased the yield of ‘Gigante’ cactus pear. The application of 60 m3 ha-1 of biofertilizer at the interval of 14 days increased the yield of ‘Gigante’ cactus pear.

Growth, biomass, and energy quality of Acacia mangium timber grown at different spacings

Abstract: The objective of this work was to assess the effect of spacing on the growth, biomass allocation, and wood quality for energy purposes of Acacia magium. A randomized complete block design was carried out with three replicates and five treatments consisting of trees planted at different spacings: 2.0x2.0, 2.5x2.5, 3.0x2.0, 3.0x2.5, and 3.0x3.0 m. At 67 months after planting, the following species parameters were evaluated: performance (mortality, diameter growth, height, bark factor, and bark and biomass volume yield) and wood energy quality (basic density, higher-calorific value, ash, fixed carbon, and volatile materials) through the analysis of variance. Plant spacing did not affect volume and biomass production per hectare nor wood quality for energy purposes. The widest spacing (3.0x3.0 m) provides better individual growth, and the narrowest one (2.0x2.0 m) produces smaller trees, but with the highest percentage of dry biomass in the trunk, and can show the best energy potential at a rotation age from 40 to 50 months.

Comparison of traditional and modern deficit irrigation techniques in corn cultivation using treated municipal wastewater

PurposeDeclining water resources, increasing drought period and increasing irrigated area cause a shift to deficit irrigated production which is not based on full water requirement. This study was conducted to investigate the impacts of two different deficit irrigation methods, including traditional deficit irrigation (TDI) and partial root-zone drying (PRD) on water use efficiency (WUE) in corn cultivations located at the lands close to the Shahrekord wastewater treatment plant.MethodsA factorial design was employed, consisted of fifteen treatments and three replications. The first factor was three water applications, including 60, 80 and 100 (control) percent of plant water requirement. The second factor was three water sources, including 100% fresh water (FW), 50% water and 50% wastewater (5050), 100% wastewater (WW). T-Tape irrigation type system was used for irrigation of corn (Zea mays L.). The third factor was water management in three levels: full irrigation (FI), PRD and TDI.ResultsThe result showed that dry and fresh weight, leaf area index (LAI), dry biomass percentage and WUE were affected by water requirement at 5% probability level expect of height plant that is affected at 1% probability level. Water quality was affected on all the study indicators of corn plant expect of WUE. WUE among PRD by deficit irrigation treatments were higher than TDI and it was the minimum in FI. The dry and wet weight and LAI were maximum at FI and then PDR80 than TDI80. The height of corn plants were high at FI and TDI80 than PRD80.ConclusionFinally, wastewater application in treatment named 5050-PRD80 and 5050-TDI80 compensated water deficit in WUE, LAI and dry biomass percentage. PRD method recognized more suitable than TDI for corn plants.

Root to branch wood anatomical variation and its influence on hydraulic conductivity in five Brazilian Cerrado species

The wood anatomy of the root, stem (base, middle, top) and branch of Anadenanthera peregrina, Copaifera langsdorffii, Handroanthus ochraceus, Ocotea corymbosa and Xylopia aromatica growing naturally in the Brazilian Cerrado is investigated. The important findings are correlated with hydraulic architecture and mechanical requirements. The presence of hydraulic bottlenecks (also referred to as hydraulic constrictions) is evident in the transition from root to stem, but no such transition is observed from stem to branch in other four species except for Xylopia aromatica. Compared with solitary vessels, proportion of multiple vessels is higher in the roots of Anadenanthera peregrina and Copaifera langsdorffii, as well as in the roots and stem-base of Xylopia aromatica indicating a tendency toward higher safety of roots from embolism as compared to the stem. Dimensions of rays, fibers and dry biomass percentage did not clearly show variations in these cells to influence the mechanical strength. Besides reducing hydraulic conductivity, decrease in vessel diameter from the root to the stem base may also impact mechanical strength by reducing empty spaces (vessel lumen). We concluded that the wood of the stem base of the species investigated shows mechanism to safeguard from air embolism by producing narrower vessels, which can protect the main stem from constant loss of conductivity.

Sodium accumulation contributes to salt stress tolerance in lettuce cultivars

Increasing soil salinity of irrigated agricultural areas represents a major environmental stress factor that impairs the production of many salt-sensitive crop plants. Different lettuce cultivars were studied for identification of more tolerant ones, based on physiological properties. Five selected lettuce cultivars were grown hydroponically, salt stress was induced by 50 mM and 100 mM of NaCl. The cultivars exhibited differential reduction in shoot fresh weight. The highest sodium and free proline accumulation in the shoot of the most tolerant cultivar, associated with a moderate decrease of the root hydraulic conductance and of the leaf stomatal conductance, can be related to a better defense mechanism against osmotic stress. Salt exposure increased the potassium and calcium ion content of the xylem sap, which may be important for an efficient osmotic adjustment needed to support leaf expansion. The fact that the highest amount of Na+ was found in the shoot of the most tolerant cultivar, and the lowest in the most sensitive one, reflects that in lettuce Na+ exclusion is not a main strategy for salt tolerance. Lettuce is a good example for the case in which salinity tolerance is related not to exclusion, but to inclusion of sodium ions in the shoot system. For salt tolerant varieties the marketable yield has a higher dry biomass percentage, leaves of plants grown under high salinity are crispier, darker green and have a slight salty taste.

The analysis of macroalgae biomass found around Hawaii for bioethanol production

Macroalgae commonly found in the ocean around Hawaii were collected from near shore locations and their potential as biomass feedstock for fermentative ethanol was investigated. A green alga, Ulva reticulata, was selected for further analysis. This species forms large complex structures that grow quickly and has high dry biomass percentage (20%), soluble carbohydrates (18%), and high total carbohydrates along with low quantities of lignin (13%). During acid saccharification, it was determined that 49% of the total mass was observed as sugars in the hydrolysate; however, fermentation was problematic. Enzymatic saccharification using cellulase from Trichoderma reesei was attempted which recovered a measured maximum of 20% glucose based on the initial dry mass. Fermentation successfully converted all the glucose to ethanol. The measured ethanol yield corresponded to approximately 90 L per tonne of dried macroalgae.

Effects of experimental submersion on survival, growth, and dry biomass allocation of the rare salt marsh plant Limonium girardianum

In order to define the flooding tolerance capacity of Limonium girardianum according to growth development stage, we submerged 200 seedlings and 200 four-month-old juveniles in fresh water. During the eleven weeks of the experiment, we recorded the survival, growth and dry biomass of both seedlings and juveniles. Every week, we removed a group of ten seedlings and ten juveniles from submerged conditions and put them in drained conditions. We measured the leaf production rate and variation in total leaf area of both seedlings and juveniles. We measured the final above and below-ground dry biomass for both seedlings and juveniles. The seedlings started to die from week-2, while juveniles started to die from week-7. Fifty percent of seedlings died over a six weeks period, while fifty percent of juveniles died over a ten-week period. Beyond seven weeks and nine weeks for seedlings and juveniles respectively, total submersion stopped growth, and delayed leaf production and the increase of the total leaf area. Above-ground dry biomass significantly decreased from 30g to 10g for seedlings and from 30g to 25g for juveniles, according to flood duration. Below-ground dry biomass percentage increased from 60% to 80% between week-4 and week-7 for seedlings. Below-ground dry biomass of juveniles decreased from 80% to 50% between week-4 and week-9. Our study showed that flood-prone plant species have a different response to flood conditions according to the developmental stage. The higher sensitivity to submersion of seedlings is due to its lower survivorship, lower leaf production, lower growth and more important dry biomass decrease than juveniles. This statement can be seen as a threat for population viability in the long term since human activities, such as construction of heavy industrial infrastructures and roads, induces too long flood duration that would compromise the persistence of L. girardianum populations.

Genetic diversity of Capsicum chinensis (Solanaceae) accessions based on molecular markers and morphological and agronomic traits

We estimated the genetic diversity of 49 accessions of the hot pepper species Capsicum chinensis through analyses of 12 physicochemical traits of the fruit, eight multi-categorical variables, and with 32 RAPD primers. Data from the physicochemical traits were submitted to analysis of variance to estimate the genetic parameters, and their means were clustered by the Scott-Knott test. The matrices from the individual and combined distance were estimated by multivariate analyses before applying Tocher's optimization method. All physicochemical traits were examined for genetic variability by analysis of variance. The responses of these traits showed more contribution from genetic than from environmental factors, except the percentage of dry biomass, content of soluble solids and vitamin C level. Total capsaicin had the greatest genetic divergence. Nine clusters were formed from the quantitative data based on the generalized distance of Mahalanobis, using Tocher's method; four were formed from the multi-categorical data using the Cole-Rodgers coefficient, and eight were formed from the molecular data using the Nei and Li coefficient. The accessions were distributed into 14 groups using Tocher's method, and no significant correlation between pungency and origin was detected. Uni- and multivariate analyses permitted the identification of marked genetic diversity and fruit attributes capable of being improved through breeding programs.

The decomposition of wood products in landfills in Sydney, Australia

Three landfill sites that had been closed for 19, 29 and 46 years and had been operated under different management systems were excavated in Sydney. The mean moisture content of the wood samples ranged from 41.6% to 66.8%. The wood products recovered were identified to species, and their carbon, cellulose, hemicellulose and lignin concentration were determined and compared to those of matched samples of the same species. No significant loss of dry mass was measured in wood products buried for 19 and 29 years, but where refuse had been buried for 46 years, the measured loss of carbon (as a percentage of dry biomass) was 8.7% for hardwoods and 9.1% for softwoods, equating to 18% and 17% of their original carbon content, respectively. The results indicate that published decomposition factors based on laboratory research significantly overestimate the decomposition of wood products in landfill.

In vitro and in vivo peppermint (Mentha piperita) growth promotion by nonmycorrhizal fungal colonization.

• Here peppermint growth and terpene production of in vitro generated plants (Mentha piperita) in response to inoculation with a leaf fungal endophyte were characterized. • Peppermint plants were studied by means of morphometric, biochemical and image analysis, employing both in vitro and in pot cultures. Leaf essential oils were analysed by gascromatography-mass spectrometry. • The endophyte induced profound effects on the growth of peppermint, which responded with taller plants bearing more expanded leaves. The observed increase of leaf dry matter over leaf area suggested a real improvement of peppermint metabolic and photosynthetic apparatus. Root architecture was of the herring-bone type, showing greater dry biomass percentage over the total. A sustained lowering of (+)-menthofuran and an increase of (+)-menthol percentage concentrations were found in plants from both in vitro and pot cultures. • The study represents the first report on specialized endophytic fungi in peppermint green tissues and highlights some of the principal morphological and biochemical aspects of this mutualism. Effects exerted on plant growth and essential oil production in peppermint suggest further biotechnological applications.