Exploring the potential to capture variation in grain-straw yield and straw quality traits of tef [Eragrostis tef (Zucc.) Trotter] varieties.

Tef [Eragrostis tef (Zucc.) Trotter] is an indigenous Ethiopian cereal which helps provide healthy and nutritious diets for people and a palatable straw for livestock feed. This study was conducted to determine the variation in grain-straw yield and straw quality traits of 35 tef varieties and a local check grown in two locations for two years. Straw crude protein (CP), in vitro organic matter digestibility (IVOMD), metabolizable energy (ME) and the yields of grain (GY) and straw (STY) were significantly (P < 0.01) affected by variety, environment and their interactions. GY, CP, ME and IVOMD were significantly higher in the Debre Zeit site compared to Holetta and, except for GY, in 2016 compared to 2015. About 150% and 25% higher mean CP content was recorded in Debre Zeit than in Holetta, and in 2016 than 2015, respectively. Positive and significant (P<0.01) associations were observed between GY and STY, among CP, ME and IVOMD, and among NDF, ADF and ADL. Among all studied varieties, Melko produced the highest grain-straw yield and best fodder quality traits. Based on the yields and qualities of both grain and straw, the production of Gimbichu, Quncho and Gola varieties conferred more than 40% economic advantage over the local check in the local markets. Our study generally identified varieties with high grain-straw yield and/or straw quality traits which provided economic advantages for tef production and an opportunity for future utilization in tef improvement programs.

Evaluation of paper straws versus plastic straws: Development of a methodology for testing and understanding challenges for paper straws

New alternatives to plastic straws are being considered due to consumer demands for sustainability and recent changes in government policies and regulations, such as bans on single-use plastic products. There are concerns regarding paper straw quality and stability over time when in contact with beverages. This study evaluated the performance and properties of commercially available paper straws and their counterpart plastic straws in various intended applications. The physical, mechanical, and compositional characteristics, as well as the liquid interaction properties of the straws, were determined. The paper straws were composed mainly of hardwood fibers that were hard sized with a hydrophobic sizing agent to achieve a contact angle of 102° to 125°. The results indicated that all the evaluated paper straws lost 70% to 90% of their compressive strength after being in contact with the liquid for less than 30 min. Furthermore, the paper straws absorbed liquid at approximately 30% of the straw weight after liquid exposure for 30 min. Increased liquid temperatures caused lower compressive strengths and higher liquid uptake in the paper straws. This report provides directions and methods for testing paper straws and defines current property limitations of paper straws relative to plastic straws.

Comparative Grain Yield, Straw Yield, Chemical Composition, Carbohydrate and Protein Fractions, In Vitro Digestibility and Rumen Degradability of Four Common Vetch Varieties Grown on the Qinghai-Tibetan Plateau

Four varieties of common vetch, including three improved varieties (Lanjian No. 1, Lanjian No. 2, and Lanjian No. 3) and one local variety (333A), were evaluated for varietal variations in grain yield, straw yield and straw quality attributes on the Qinghai-Tibetan Plateau. Crops were harvested at pod maturity to determine grain yield, straw yield, harvest index, and potential utility index (PUI). Straw quality was determined by measuring chemical composition, carbohydrate and protein fractions, in vitro gas production and in situ ruminal degradability. Results showed a significant effect (p < 0.01) of variety on the grain yield [875.2–1255 kg dry matter (DM)/ha], straw yield (3154–5556 kg DM/ha), harvest index (15.6–28.7%) and PUI (53.3–63.2%). Variety also had a significant effect on chemical composition, carbohydrate and protein fractions (p < 0.05) except non-structural carbohydrates and rapidly degradable sugars. Significant differences (p < 0.05) were observed among the varieties in potential gas production [188–234 mL/g DM], in vitro organic matter (OM) digestibility (43.7–54.2% of OM), and metabolizable energy (6.40–7.92 MJ/kg DM) of straw. Significant differences (p < 0.001) were also observed among the varieties in rapidly degradable DM fraction and effective DM degradability of straw; however, no difference was observed in other DM degradation parameters and neutral detergent fiber degradation parameters. In conclusion, based on straw yield and quality, Lanjian No. 1 has the greatest potential among the tested varieties as a crop for supplementing ruminant diets for smallholder farmers on the Qinghai-Tibetan plateau.

Improving Fermentation of Steamed Stalk to Feed Using Candida utilis and Pachysolen tannophilus

In order to improve the protein content of straw feed and reduce the amount of nutrients added, in this paper, the cell wall structure of corn stalk was destroyed by thermophilic digestion and the polysaccharide was degraded into monosaccharide by complex enzyme, and then transformed into bacterial protein by double strain Candida utilis 1807 and Pachysolen tannophilus 1771 fermentation. Single factor experiments and orthogonal test were made to obtain the best process for the feed of double-bacteria synchronous fermentation of stalks. The optimum amount of each nutrient and the inoculation amounts of double bacteria (accounts for the percentage of the original dry straw quality): ammonium sulfate 6.79%, urea 2.72%, yeast powder 1.63%, magnesium sulfate 0.27%, Candida utilis 54.31% and Pachysolen tannophilus 54.31%; The operational parameters of fermentation process were: fermentation temperature 29°C, rotate speed 100 r/min and fermentation time 55 hours. The yield of stalk feed and crude protein was 82.04%, 23.33%, respectively. The crude protein content of stalk feed was 28.44%, which was 4.33 times of original dry stalk. The results showed that the multi-strain distribution and degradation of protein production provide important significance for corn straw bio-utilization.

Content of microorganisms in cereal straw

Straw is an important agricultural raw material with application in agriculture, energy sector and other fields of activity. A major impact on reduction of the straw quality is that of an excessive content of microbiological agents caused by improper storage. By simulation of different conditions of storage the development of microorganisms (moulds and yeasts) was determined in the straw of wheat under different water content. Total content of microorganisms varied in a wide range from 10³up to 10⁵ CFU/g. The excessive amount of these microorganisms results not only in a reduction in the quality of raw material due to the development of biodegradable processes, but also causes an increase of hygienic risks in the nearby area.

The effect of wheat straw quality on the rate of its mineralisation in soil

The aim of this study was to assess the effect of straw of two spring wheat cultivars, Tybalt – with the culm filled with pith, and Ostka Smolicka – with the hollow culm, added to light textured soil, on the mineralisation rate of organic matter. The incubation experiment was established under laboratory conditions and comprised three experimental combinations: K1 was soil with an addition of pith-filled culms, K2 – soil with an addition of straw with hollow culms, and K0 – the control with no straw added. In all the combinations, mineral fertilisation was applied in the form of urea. Incubation lasted for 14 months. At specific dates the amounts of CO2 released within 24 h and pH values were recorded. The rate of organic matter mineralisation was expressed in mg CO2·d−1. Analyses showed that the addition of straw, both with pith-filled and hollow culms, significantly influenced the mineralisation of organic matter in the first months of incubation. Mineralisation was most intensive in the soil incubated with straw with hollow culms. The large amount of released carbon dioxide in the first days of incubation caused a decrease in pH both in the control soil and in soils with the addition of straw. The change in the soil reaction to its initial value was recorded at day 222 for the soil combination K0 and at day 250 of incubation in soils fertilised with straw.