Quality Of Alfalfa Research Articles

Scientific basis of the influence of the period of harvest (phase) on blood mass yield of claffer

A person should take about 90–100 g of protein day, largely from animal sources, despite the growing need for vegetable protein. Animal feed with insufficient protein causes them to consume excessive amounts of fodder, increasing their need for plant protein. The production of plant protein must significantly expand in order to fulfill the demands of animal husbandry. The demand for vegetable protein is on the rise, and it is recommended that an individual should consume approximately 90-100 g of protein per day, primarily sourced from animals. Insufficient protein in animal feed results in a higher consumption of fodder, which in turn necessitates an increased intake of plant protein. The experiment took place at the Tashkent State Agrarian University's experimental farm, located in typical gray soil conditions. The soil consists of a 25cm driving layer and a 50cm humus layer, with 1% humus, pH level of 7, and mobile phosphorus, chlorine, and nitrogen levels of 1.5-2.9 mg/100g, 22-25 mg/100g, and 3.8-4.2 mg/100g, respectively. It was found that the nutritional quality of alfalfa is also influenced by its growth stage, with the highest protein content observed in the stem growth phase in the Tashkentskaya-1728 variety. By the time of flowering, the protein content has decreased significantly.

Irrigation and Phosphorus Management of Alfalfa Under Semi-Arid Conditions

The frequency of irrigation and deficit irrigation management are drawing attention because water resources are becoming limited year by year, especially in the last decade. Besides, the rate and application time of P fertilization gained more importance just after the researchers found out it is more effective than N-fertilizing for alfalfa cultivation. This study aimed to determine the effects of different irrigation managements (seasonal deficit, intervals of 5, 7, and 9 days), phosphorus application season (autumn and spring), and the rate of P fertilizer (0, 30, 60, 90 kg ha-1) on the yield and forage quality of alfalfa. The experiment was conducted in the 2019-2020 years, which was the 3rd and the 4th years of alfalfa respectively, under semi-arid Mediterranean conditions. The stand height and fiber content (NDF) were higher in the autumn application. However, forage contained more nitrogen in the spring application. A higher amount of water (800 mm) with higher irrigation frequency (5 days – I5d) caused a reduction in yield due to water excess. The yield was the highest (21.34 t ha-1) and the forage quality was better in 448 mm water application with 9 days intervals (I9d). Seasonal deficit water management caused a significant loss in yield and quality. Nevertheless, 18.04 t ha-1 dry matter yield with 24.05 % CP content was recorded at seasonal deficit water management. P fertilization increased the yield and forage quality. The yield was the highest (20.23 t ha-1) at the rate of 90 kg ha-1 P fertilizer, but yield and forage quality characteristics were similar between 30, 60, and 90 kg ha-1 P. The results showed that P fertilization could be done in both autumn and spring at the rate of 30 kg ha-1 and 448 mm water could be applied at 9 days intervals for fulfilling performance under semi-arid Mediterranean conditions. When water resources are very scarce, the seasonal water deficit should be applied, especially in late summer.

Dry matter yield and nutritive quality of alfalfa (Medicago sativaL.) cultivars grown in sub-humid areas in Ethiopia

Alfalfa (Medicago sativa L.) is one of the most important perennial forage legumes with high nutritional quality. Four alfalfa cultivars were sown in randomized block design with four replications to evaluate their dry matter yield and nutritional quality under rain-fed conditions during 2016–2017 at Masha, southwest Ethiopia. Percentage of plot cover, plant height, leaf to stem ratio, dry matter yield, crude protein yield, and dry matter (DM), ash, crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL) were measured. The combined analysis revealed that days to 50% flowering were significantly (P < 0.01) influenced by cultivar and cropping year. Dry matter yield was significantly affected by cultivar and cultivar vs year interaction. Hairy Peruvian scored the highest plot cover percentage followed by Pioneer 00407, Hunter River, and Magna 788. The overall mean for days to 50% flowering indicated that Hunter River reached more lately than others. We observed that leaf-to-stem ratio and plant height were insignificant among the cultivars. Hairy Peruvian gave a higher dry matter yield (15.0 t ha−1) followed by Pioneer 00407 (12.1 t ha−1), Magna 788 (11.5 t ha−1), and Hunter River (10.5 t ha−1). The chemical compositions did not vary significantly (P > 0.05) due to cultivar differences. It could be concluded that, of the tested cultivars, Hairy Peruvian is an appropriate cultivar for biomass production potential under rain-fed conditions for sub-humid areas of southwest Ethiopia.

Fertilization strategy affects crop nutrient concentration and removal in semi‐arid U.S. Northwest

AbstractAccess to livestock manure is increasing in semi‐arid cropping systems of U.S. Northwest prompting evaluation of fertilization strategies on regional production systems. A study conducted from fall 2012 to 2019 used: fall‐ or spring‐applied dairy manure (56 Mg ha−1), fall‐applied composted dairy manure (33 Mg ha−1), spring‐applied urea or SUPERU (Koch Agronomic Services), and a control (n = 6) on a corn (Zea mays L.)–barley (Hordeum vulgare L.)–alfalfa (Medicago sativa L.)–alfalfa–alfalfa rotation. The effects of fertilization strategies on (a) soil nutrients, (b) crop tissue nutrient concentration and removal, and (c) digestibility and energy content of forages are discussed. Compost and manure additions increased corn silage N, P, K, respectively, by 0.86, 0.28, and 2.4 g kg−1 over other treatments; silage Ca and Mg were depressed 0.4 and 0.53 g kg−1 by manure applications. Barley grain Premoval and Kremoval increased 5.10 and 7.65 g kg−1 under manure applications relative to urea and SUPERU treatments while crude protein (CP) (19.1 g N kg−1) neared limits of high‐quality malt extract (16–19 g N kg−1). Compost and manure increased alfalfa K by 2.3 and 5.5 g kg−1 over other treatments, approaching levels of concern for hypocalcemia in dairy cattle (≥30 g K kg−1). No major impact on corn silage or alfalfa quality parameters, were observed. Present Idaho nutrient removal estimates were representative of corn and alfalfa, but not barley in which observed N removal was 28% lower. In 17 of 18 instances, contrast testing suggested nutrient removal differed under organic amended treatments, suggesting nutrient removal modifiers in production systems receiving organic amendment may need established.

Yield and quality of alfalfa (Medicago sativa L.) in response to fertilizer application in China: A meta-analysis.

In China, alfalfa (Medicago sativa L.) often grows in marginal land with poor soil fertility and suboptimal climate conditions. Alfalfa production cannot meet demands both in yield and quality. It is necessary to apply fertilizers to achieve high yields and produce high-quality alfalfa in China. However, there is no understanding on the impact of fertilizer application on alfalfa production and the possible optimal application rates across China. We conducted a meta-analysis to explore the contribution of fertilizer application to the yield and quality of alfalfa based on a dataset from 86 studies published between 2004 and 2022. The results showed that fertilizer application not only increased alfalfa yield by 19.2% but also improved alfalfa quality by increasing crude protein (CP) by 7.7% and decreasing acid detergent fibre by 2.9% and neutral detergent fibre by 1.8% overall compared to the non-fertilizer control levels. The combined nitrogen (N), phosphorus (P) and potassium (K) and combined NP fertilizer applications achieved the greatest yield and CP concentration increases of 27.0% and 13.5%, respectively. Considering both yield and quality, the optimal rate of fertilizer application ranged from 30 to 60kg ha-1 for N, 120 to 150kg ha-1 for P and less than 120kg ha-1 for K. Meta-analysis further showed that the effect of fertilizer application on yield was greater in low soil organic matter (SOM) soils than in high SOM soils. In conclusion, fertilizer application is an effective strategy to improve the yield and quality of alfalfa in China, especially that grown in low SOM soils. This study is helpful for optimizing fertilization schedules of alfalfa in China.

First report of alfalfa root rot caused by Trichothecium roseum in China.

Alfalfa (Medicago sativa L.) is perennial leguminous forage, which is cultivated throughout the world due to its high yield, high quality, satisfactory palatability, and wide adaptability. With the increase of planting area in China, root diseases caused by Fusarium spp., Sclerotium rolfsii, Phytophthora spp. (Yang et al. 2022), and new pathogens have been found that reduce the yield and quality of alfalfa and cause economic losses (Li at al. 2019). In 2021, an alfalfa disease occurred under conditions of high temperature and high humidity at the Jiaozhou Experimental Base of Qingdao Agricultural University (Jiaozhou Modern Agricultural Science and Technology Demonstration Park, 36.33°N 120.40°E, Qingdao, Shandong, China), and about 2 ha of alfalfa were infected. The disease affected up to 35% of the plants and caused grass spots. Infected plants developed black-brown lesions with irregular shapes on roots with yellowing of the foliage; the leaves of the whole plant turned yellow. In the late stage of the disease, defoliation occurred and the plants stopped growing, wilted and died. Ten infected plants with typical symptom were collected for isolation and identification of pathogen. The infected roots were cut into 3-5 mm2 sections and then soaked in 75% ethanol for 30 s, followed by a 3-minute immersion in 2% sodium hypochlorite for surface sterilization. Next, the tissues were rinsed in sterile water five times and then placed on potato dextrose agar (PDA) medium. After three subcultures and subsequent single spore isolation, one representative strain named as DC1 was isolated from the infected roots. Based on morphological observation, the colony of DC1 was flat, granular, and powdery in appearance. Four days after inoculation on PDA medium, the size of the colony were 2.1-2.6 cm. After 8 to 20 days, the colonies were initially white and gradually change a light pink to peach color. The conidia are two-celled (Hamid et al. 2014), elliptic to pear-shaped, colorless or translucent, smooth to slightly rough with thick walls. The size of conidia ranged from 11.3 to 23.5 μm long × 6.1 to 12.7 μm wide (n =30). For the identification, the rDNA--ITS gene of the fungus was amplified using the primers ITS1/ITS4 (White et al.1990), and the EF1α gene was amplified using primers EF1-983F/EF1-2218R (Rehner and Buckley 2005). Then the PCR amplicons were cloned into the pCE2 TA/Blunt-Zero vector. The results of the rDNA-ITS (OM049197.1, 515 bp) and EF1α (OM069381.1, 926 bp) sequences were deposited in GenBank. DNA analysis showed that the two sequences were 100% similar to the rDNA-ITS sequence (MN882763.1) and EF1α sequence (DQ676610.1) of Trichothecium roseum, respectively. A pathogenicity test was done by placing one piece (0.5 cm in diameter) of fungal culture (PDA plug) 1cm below the crown of 40-day-old healthy alfalfa (cv. Zhongmu No.3) plants, 3 replicates and 20 plants in each replicate. PDA plug without the pathogen were used for control. All plants were cultivated in a growth chamber at 25±1°C with a light cycle of 15 h (90% relative humidity). After 18 days, the roots of inoculated plants had dark brown lesions and the leaves of their plants turn yellow, while those control plants had no symptoms. To fulfilling Koch's postulates, the same pathogen was re-isolated from necrotic root tissue of inoculated plants and confirmed by morphology and the rDNA-ITS and EF1-α sequences. Based on disease symptoms, morphological characteristics DNA sequences and pathogenicity, the pathogen of alfalfa disease in Jiaozhou Experimental Base of Qingdao Agricultural University was identified as T. roseum. To our knowledge, this is first report of T. roseum causing alfalfa root rot. The newly emerging disease may pose threat to alfalfa production of central and southern China in future.

Differential Physiological Characteristics and Fungal Composition of Alfalfa under Salt Stress in Degraded Grasslands

Alfalfa (Medicago sativa L.) is an important source of livestock feed used to address the imbalance between livestock and forage production in China. However, much of the grasslands have a high salt content, which seriously affects the quality and yield of alfalfa. There are many kinds of fungi that play an important role in alfalfa growth and nutrient synthesis. The response of the fungi of alfalfa to salinity is poorly understood. In this study, the physiological characteristics and the fungal community composition of alfalfa under different salt stress conditions were investigated. Salt stress had a great impact on the physiological characteristics and the fungal community composition of alfalfa. The activity of invertase increased significantly under salt stress; the content of water and starch decreased; and the content of crude protein (CP) and soluble sugar increased under mild salt stress. With the increase in salt stress, the relative abundance of Ascomycetes increased, while the relative abundance of basidiomycetes decreased. This showed that the changes in the fungal community may be related to the adaptability of alfalfa plants to salt stress. These findings contribute to a better understanding of alfalfa physiological characteristics and nutrient synthesis under salt stress and deepen our understanding of alfalfa–fungi interactions in the saline soil environment of grasslands.

Effects of Different Bio-fertilizer Treatments on the Growth and Quality of Alfalfa

Background: Alfalfa has small seeds and is intolerant to deep-sowing. We investigated seed emergence of alfalfa variety “Longmu 801” from deep-sowing and its quality improvement through different bio-fertilizer treatments. Methods: Seven fertilization treatments were tested: CK: no fertilization (control), A: amino acid fertilizer, B: amino acid fertilizer + selenium-rich yeast fertilizer diluent, C: amino acid fertilizer + selenium-rich yeast fertilizer dilution + microbial agent, D: amino acid fertilizer + algae extract, E: amino acid fertilizer + microbial agent and F: amino acid fertilizer + selenium-rich yeast fertilizer diluent + microbial agent + algae extract. Result: The bio-fertilizer treatments improved the alfalfa seedling emergence, growth and quality. Treatment E increased the emergence rate, plant height and yield by 10.6%, 41.0% and 68.9%, respectively; decreased the stem-leaf ratio, neutral detergent fiber and acid detergent fiber by 41.7%, 3.7% and 3.17%, respectively and increased crude protein, crude fat and relative feeding value by 2.5%, 0.5% and 8.6%, respectively; compared with that of the control. Soaking alfalfa seeds in 0.2% amino acid fertilizer and applying 13.5 g microbial agent was suggested as the most efficient fertilization technique to promote alfalfa emergence, growth and quality and provide profits to farmers due to its low cost.

Effects of laccase and lactic acid bacteria on the fermentation quality, nutrient composition, enzymatic hydrolysis, and bacterial community of alfalfa silage.

Ensiling has long been as a mainstream technology of preserving forage for ruminant production. This study investigated the effects of bioaugmented ensiling with laccase and Pediococcus pentosaceus on the fermentation quality, nutritive value, enzymatic hydrolysis, and bacterial community of alfalfa. The application of laccase and Pediococcus pentosaceus combination was more potent in modulating the fermentation quality of silage than laccase and Pediococcus pentosaceus alone, as indicated by higher lactic acid contents and lactic acid to acetic acid ratios, and lower pH, dry matter losses, and ammonia nitrogen contents. Moreover, treatments with additive enhanced protein preservation and structural carbohydrate degradation, while increasing true protein and water-soluble carbohydrate contents. By promoting lignin degradation, treatments containing laccase further facilitated the release of sugars from cellulose compared with treatment with Pediococcus pentosaceus alone. The additive treatments reduced the bacterial diversity and optimized the bacterial community composition of silage, with an increase in the relative abundance of desirable Lactobacillus and a decrease in the relative abundance of undesirable Enterobacter and Klebsiella. PICRUSt functional prediction based on Kyoto Encyclopedia of Genes and Genomes (KEGG) databases revealed that PL and LPL treatments increased the metabolism of membrane transport, carbohydrate, and terpenoids and polyketides related to fermentation activities. It can be concluded that bioaugmented ensiling with laccase and Pediococcus pentosaceus combination can be an effective and practical strategy to improve silage fermentation and nutrient preservation of alfalfa silage.

Remote Sensing on Alfalfa as an Approach to Optimize Production Outcomes: A Review of Evidence and Directions for Future Assessments

Alfalfa (Medicago sativa L.) is one of the most relevant forage crops due to its importance for livestock. Timely harvesting is critical to secure adequate forage quality. However, farmers face challenges not only to decide the optimal harvesting time but to predict the optimum levels for both forage production and quality. Fortunately, remote sensing technologies can significantly contribute to obtaining production and quality insights, providing scalability, and supporting complex farming decision-making. Therefore, we aim to develop a systematic review of the current scientific literature to identify the current status of research in remote sensing for alfalfa and to evaluate new perspectives for enhancing prediction of both biomass and quality (herein defined as crude protein and fibers) for alfalfa. Twelve papers were included in the database from a total of 198 studies included in the initial screening process. The main findings were (i) more than two-thirds of the studies focused on predicting biomass; (ii) half of the studies used terrestrial platforms, with only 33% using drones and 17% using satellite for remote sensing; (iii) no studies have used satellites assessed alfalfa quality traits; (iv) improved biomass and quality estimations were obtained when remote sensing data was combined with environmental information; (v) due to a direct relationship between biomass and quality, modeling them algorithmically improves the accuracy of estimation as well; (vi) from spectral wavelengths, dry biomass was better estimated in regions near 398, 551, 670, 730, 780, 865, and 1077 nm, wet biomass in regions near 478, 631, 670, 730, 780, 834, 933, 1034, and 1538 nm, and quality traits identified with narrow and very specific wavelengths (e.g., 398, 461, 551, 667, 712, and 1077 nm). Our findings might serve as a foundation to guide further research and the development of handheld sensors for assessing alfalfa biomass and quality.

Yield and quality properties of alfalfa (Medicago sativa L.) and their influencing factors in China

Alfalfa (Medicago sativa L.) is the most valuable perennial forage crop, and assessing its yield and quality properties is essential to evaluate forage value of livestock production. However, regional patterns and controlling factors of the yield and quality of alfalfa have not been well documented. In this study, using a dataset of 7166 observations from 301 sites across the country collected from 334 publications, we explored the relationships between the yield and quality properties of alfalfa in China and the effects of environmental factors and management practices on them. The average dry matter yield of alfalfa was 11.18 ± 6.69 Mg ha-1, with average crude protein, ether extract, crude fiber, acid detergent fiber, neutral detergent fiber, crude ash, nitrogen-free extract, calcium, phosphorus and relative feed values of 19.05 ± 2.87%, 2.62 ± 0.97%, 27.16 ± 5.21%, 31.29 ± 5.58%, 40.48 ± 6.34%, 9.49 ± 1.59%, 38.67 ± 7.49%, 1.68 ± 0.55%, 0.25 ± 0.12%, and 151 ± 31.94, respectively. Alfalfa quality decreased with increasing yield. Geographically, alfalfa had higher yield and crude protein content in South China than in other regions. Quality was positively correlated with both precipitation and temperature, while yield showed a positive relationship with temperature but no significant relationship with precipitation. High soil nutrient availability (e. g., soil available nitrogen, SAN; soil available phosphorus, SAP; soil available potassium, SAK) improved the yield, while high SAN and SAP contents increased the crude protein content. The alfalfa yield increased and the quality decreased with advancing maturity and age, whereas increasing the number of harvests may benefit the quality. This study documents comprehensive information on the yield and quality of alfalfa and provides insights for policy makers for the effective management and sustainable development of alfalfa production.

Occurrence and Nutrition Indicators of Alfalfa withLeptosphaerulina in Chifeng, Inner Mongolia

Alfalfa Leptosphaerulina leaf spot is a common disease of alfalfa, while its effect on alfalfa quality has not been reported. The present study aimed to investigate the alfalfa Leptosphaerulina leaf spot in Chifeng City, Inner Mongolia, China and determine the quality of alfalfa plants and leaves with different scales. The incidence and disease index of nine alfalfa cultivars ranged from 12.1% to 59.8% and 10.0 to 51.0, respectively. The incidence of the Optimus cultivar and the disease index of the WL168 cultivar were significantly higher than those of the other cultivars. Therefore, different scales (0–4) of the alfalfa WL168 plant and leaves were used to determine their nutritional levels. Compared with healthy plants and leaves, the severity of alfalfa leaf spot on a scale of 4 decreased by 3.7% to 29.4% or 1.7% to 40.7%, respectively, in 18 nutrients; and increased by 12.0% to 14.5% or 17.8% to 26.9% in the Rumen protein (RUP), acid detergent fiber (ADF) and neutral detergent fiber (NDF), respectively. In addition, the crude protein (CP) content of alfalfa plants or leaves based on a severity scale of 4 decreased by 16.7% and 6.2%, respectively. Correlation analysis revealed a strong negative correlation between 18 nutritional contents and disease severity, except for NDF, ADF and RUP. Conclusively, alfalfa Leptosphaerulina leaf spot strongly influences the plant and the leaves’ nutrient content in the plant.

Evaluation of cut alfalfa moisture content and operative conditions by hyperspectral imaging combined with chemometric tools: In-field application

High quality of hay or silage can be obtained by monitoring the moisture level at mowing or harvest time to reduce the losses of yield and nutrients and preserve feeds in the long term. Mechanical conditioning is one of the most common ways to increase the rate of water loss from forage during drying. Near Infrared (NIR) spectroscopy is a good alternative to the classical gravimetric method to timely provide information on forage moisture content. The aim of this work was to evaluate the potential of in-field Vis/NIR hyperspectral imaging combined with chemometric tools to monitor alfalfa parameters after conditioning. Partial LeastSquares Discriminant Analysis (PLSDA) models were developed to discriminate samples according to several operative conditions (level of conditioning, field type, time after conditioning, and time of day) and yielded good discrimination power (mean sensitivity = 87%, mean probability = 89%). Moisture content was estimated by Partial LeastSquares (PLS) models obtaining determination coefficient (R 2 ) = 0.86 and Root Mean Square Error (RMSE) = 2.00% (external validation). The number of spectral bands was reduced by using the Variable Importance in Projection (VIP) method, passing from 272 to 74 bands. Further PLS models were built considering the reduced variable numbers and achieved comparable results to those obtained with the full spectra, demonstrating that reduction of the number of variables did not affect the goodness of the models. Finally, the best PLS model was applied to each pixel of the hyperspectral images to obtain false colour images. Pixels having similar colours were characterized by comparable moisture content. The models developed may be useful to determine moisture content of alfalfa remotely and in real-time during mowing or harvest procedures. • Quality of alfalfa after cutting was evaluated. • In-field Vis/NIR hyperspectral imaging was used. • Regression models to predict moisture content were developed. • The samples were discriminated according to several operative parameters. • The models could be used remotely or in real-time during mowing or harvest procedures.

Effects of Harvesting Period and Storage Duration on Volatile Organic Compounds and Nutritive Qualities of Alfalfa

Harvest time and storage time had significant effects on nutrient quality and Volatile Organic Compounds (VOCs) of alfalfa. The objective of this study was to use headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) to analyze alfalfa at different harvest periods (budding stage, early blooming, full blooming), and storage for 0 d, 90 d, 180 d, 270 d, and 360 d, the dynamic changes in VOCs and nutritional quality. Results indicated that ketones, aldehydes, alcohols and esters were the main volatile components of alfalfa VOCs, accounting for 87.41%, 88.57% and 90.85% of the total volatile components at budding stage, early blooming and full blooming, respectively. VOCs and nutrient quality of alfalfa varied significantly in different harvest periods; delayed harvesting significantly reduced alfalfa aldehydes, alcohols, crude protein (CP), and total digestible nutrients (TDN) and significantly increased ketone, dry matter (DM), acid detergent fiber (ADF) and neutral detergent fiber (NDF) contents (p &lt; 0.05). After Comprehensive consideration ofthe yield, nutritional quality and VOCs of alfalfa, the best harvest time was determined to be the budding stage. The VOCs and nutrient quality of alfalfa were significantly different at different storage durations, and ketones, ADF and NDF were significantly increased and significantly reduced DM, CP and TDN (p &lt; 0.05). Ketone content and neutral detergent fiber (NDF) content had a significant positive correlation, (NDF F = 5.5, p = 0.024). Storage 360 d 2-methylbutyraldehyde (musty), 1-octen-3-one (earthy musty odor) content increased. These may be the key compounds that causes the smell of fresh alfalfa to fade away and a musty smell to emerge.

Effect of Seeding Ratios of Alfalfa (Medicago sativa) and Rhodes Grass (Chloris gayana) Mixtures on Dry Matter Yield and Nutritive Quality of the Fodder

The study was conducted at Adami Tulu on-station and Shashemene (FTC) sites for two (2019-2020) consecutive years with the objective to determine the appropriate proportions of seeding ratio that could optimize the dry matter yield and quality of Alfalfa and Rhodes grass mixture. The treatment was laid out in a randomized complete block design (RCBD) with three replications. Different seeding ratios of Alfalfa and Rhodes grass were arranged according to the following treatments: T1; 100% Alfalfa +0 % Rhodes, T2; 0% Alfalfa +100% Rhodes, T3; 50% Alfalfa +50% Rhodes, T4; 75% Alfalfa +25% Rhodes and T5; 25% Alfalfa +75% Rhodes. The results showed that number of tillers per plant of Rhodes grass and leaf to stem ratio of alfalfa, CP% content, NDF% and ADF% were showed a significance (p&lt;0.05) difference among the seeding ratios. The result indicated that seeding ratio has significant (p&lt;0.05) effect on the total dry matter yield of the mixture of alfalfa and Rhodes at both sites. The highest dry matter yield (8.47 t ha-1 ) was obtained from seeding ratio of 25:75, followed by seeding ratio of 50:50 (7.84 tha-1 ). The land equivalent ratios for the mixture were more than one showing that mixture of alfalfa with Rhodes is more advantageous than pure stand of forage. The highest CP% content (21.2%) was recorded from pure stand of alfalfa followed by seeding ratio 75:25 (18.5%), 50:50 (16.8%) and 25:75 (14.6%) while pure stand of Rhodes grass produced the least (11.1%) CP% value. The highest values of NDF% (34.48%) and ADF% (21.25%) were obtained from pure stands of Rhodes grass while the least values were recorded from pure Alfalfa. Thus, it can be concluded that seeding ratio combination of 50:50 could be recommended for use in the study areas and similar agro-ecologies due to its high dry matter yield, good quality and more balanced mixture of forage.

Effects of urea supplementation on the nutritional quality and microbial community of alfalfa (Medicago sativa L.) silage.

The objectives of this study were to evaluate the contribution of urea on the nutritional quality and microbial community of ensiled alfalfa (Medicago sativa L.). Alfalfa silage was control group without urea (AL), supplementation with 0.5% urea (AU1), or supplementation with 1% urea (AU2). The silage tanks were opened and sampled after silage at 0, 15, 30, and 60 d. Results showed that AU2 had higher pH, ratio of (ammonia-N)/(total nitrogen) (NH3-N/TN) and crude protein (CP) content than those in AL and AU1, while AU1 had higher acid detergent fiber (ADF) than that in AL and AU2 after 15 d silage. Richness and diversity indices of microbial communities in silage were no significant differences among AL, AU1 and AU2 group. Proteobacteria (58.23%) and Firmicutes (40.95%) were the predominant phylum in three groups during the silage process. The percent of community abundances on genera level of Enterobacteriaceae (37.61%) and Klebsiella (41.78%) in AL were a little higher than those in AU1 (30.39%, 25.02%) and AU2 (33.48%, 26.92%). These results showed that silage with urea alone could not improve the quality of alfalfa.

Effects of a Furrow-Bed Seeding System on Stand Establishment, Soil Bacterial Diversity, and the Yield and Quality of Alfalfa Under Saline Condition.

Salt stress account for large decreases in crop yield all over the world. Furrow-bed system is an efficient practice to promote plant growth in saline soil. However, the effects of Furrow-bed system on the soil environment and the growth of alfalfa (Medicago sativa L.) in salinity are not clear. For a wider and more detail evaluation, alfalfa were planted in saline sandy loam soil in fall, the effects of two plant systems (FU, furrow-bed seeding system; FL, flat-bed seeding system) on soil moisture, root zone salinity, soil microbial community structure, seedling emergence number in the early stage of the growth period and soil nutrient contents, alfalfa production characteristics in the second growth year were determined in a 2-year field experiment. The result showed that, compared with FL, FU resulted in increased soil moisture content and seedling emergence, and significantly reduced relative abundance of Actinobacteria and Choroflexi in soil, but it did not affect root zone salinity at the seedling stage. In April of second growth year, the soil salinity was lower, and the soil available phosphorus, potassium, nitrogen, and soil organic matter contents of the root zone were higher in FU than in FL. Compared with FL, FU resulted in increased yield (by 37.5%), protein content (by 3.6%), and potassium concentration (by 33.2%), and decreased ash content (by 7.7%), and sodium concentration (by 19.0%) in alfalfa plants. Pearson’s correlation analysis indicated that the increased yield was positively correlated with seedling emergence, soil available potassium, total nitrogen, and organic matter contents, and shoot potassium content and negatively correlated with shoot sodium content. The relative abundance of Actinobacteria was negatively correlated with alfalfa ash, calcium, and sodium concentrations, and positively correlated with shoot potassium content. Taken together, the results indicate that Furrow-bed seeding in early fall alleviated salt stress of alfalfa and have the potential to enhance the yield and quality of alfalfa cultivated in saline soils by improving the soil environment and regulating the growth and physiology of alfalfa. Graphical

Effects of nitrogen and phosphorus addition on growth and leaf nitrogen metabolism of alfalfa in alkaline soil in Yinchuan Plain of Hetao Basin.

Alkaline soil is widely distributed in China. Its rational utilization is an effective measure to solve land shortage and improve the environment. Alfalfa is characterized by strong salt and alkali tolerance and high yield and protein content. Nitrogen (N) and phosphorus (P) are the main nutrients for plant growth, and N metabolism is one of the primary forms of plant metabolism, which plays a vital role in quality and yield formation. The exploration of the effect of N and P on N metabolism and alfalfa growth will provide a theoretical basis for scientific fertilization for alfalfa in the alkaline soil of the Yinchuan Plain of the Hetao Basin. Therefore, a 2-year experiment of N and P addition was conducted. Six treatments were set up with a randomized block design, including without N (WN), medium N (MN), high N (HN), without P (WP), medium P (MP), and high P (HP). It was found that the MN and MP treatments increased plant height, stem diameter, stem/leaf, dry/fresh, and dry matter of alfalfa. The HN and HP treatments inhibited alfalfa biomass formation. The MN and MP treatments increased key products and enzymes of leaf N metabolism of alfalfa and promoted activities of leaf nitrate reductase (NR), glutamine synthase (GS), glutamate synthase (GOGAT), glutamic-oxalacetic transaminase (GOT), and glutamic-pyruvate transaminase (GPT), and inhibited activities of leaf protease of alfalfa. The MN and MP treatments increased contents of leaf N, P, ammonium nitrogen (NH4+-N), nitrate nitrogen (NO3−-N), total chlorophyll, and protein and reduced leaf chlorophyll a/b and amino acid, results after HN and HP treatments were opposite. The correlation among leaf P, N, NO3−-N, amino acid, and protein reached significant levels (P < 0.01). It is suggested that MN and MP treatments can improve the yield and quality of alfalfa by increasing key products and enzymes of N metabolism and can be adopted to promote alfalfa production in the alkaline soil of the Yinchuan Plain of the Hetao Basin.

Two novel screened microbial consortia and their application in combination with Lactobacillus plantarum for improving fermentation quality of high-moisture alfalfa.

To enrich lignocellulolytic microbial consortia and evaluate whether a combination of these consortia and Lactobacillus plantarum can facilitate degradation of structural carbohydrates and improve fermentation quality of high-moisture alfalfa silage. Two novel microbial consortia (CL and YL) with high lignocellulolytic potential were enriched, and had higher enzyme activities at slightly acidic conditions (pH 3.5-6.5). Two consortia were inoculated with and without combined L. plantarum (LP) to alfalfa for up to 120days of ensiling. The two consortia alone or combined with LP significantly (p<0.05) increased lactic-to-acetic acid ratios and decreased contents of volatile organic acids and NH3 -N as compared to the control. Treatments that combining microbial consortia and LP further resulted in the higher contents of lactic acid (LA), water soluble carbohydrates (WSC) and crude protein, dry matter (DM) recovery, and lower neutral detergent fibre, acid detergent lignin and cellulose contents, with YLP silage showing the lowest pH (4.41) and highest LA content (76.72gkg-1 DM) and the conversion of WSC into LA (184.03%). The addition of lignocellulolytic microbial consortia (CL or YL) to alfalfa silages as attractive silage inoculants could improve fermentation quality, and that their combination with L. plantarum appeared more effective on the degradation of structural carbohydrates and conversion of soluble carbohydrates into LA. High-moisture alfalfa is difficult to ensile due to its high buffering capacity and low readily fermentable carbohydrate contents. Microbial consortia (CL and YL) can encode a broad selection of multi-functional CAZymes, and their combination with LP could be promising for the degradation of structural carbohydrates simultaneously with improvement fermentation quality, with high performance in LA production.

Comparative transcriptome analyses reveal that the MsNST1 gene affects lignin synthesis in alfalfa (Medicago sativa L.)

As the second most abundant natural polymer, accounting for approximately 30% of the organic carbon in the biosphere, lignin plays an essential role in plant development. However, a high lignin content affects the nutritional quality of alfalfa (Medicago sativa L.), the most widely cultivated perennial legume forage crop. Histological analysis indicated that G-lignin and S-lignin were present in the stem, leaf, and petiole of alfalfa, and the deposition of lignin increased gradually in descending internodes. Neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL) contents continually increased from the top to the bottom of the stem, and ADL content showed a similar trend in leaves. Alfalfa leaves and stems from five different nodes (1, 2, 4, 6, and 8) were used as materials to investigate molecular regulatory mechanisms in lignin synthesis by RNA sequencing. Respectively 8074 and 7752 differentially expressed genes (DEGs) were identified in leaves and stems, and 1694 DEGs were common to the two tissues. “Phenylpropanoid biosynthesis” was the most enriched pathway in both leaves and stems, and 134 key regulatory genes in lignin synthesis were identified by a weighted gene co-expression network analysis. The NAC family transcription factor MsNST1 gene was highly expressed in old leaf and stem tissues. The deposition pattern of G- and S-lignin differed among M. truncatula wild-type, nst1 mutants, and overexpression lines, and the transcription levels of lignin synthesis genes such as HCT, F5H, and COMT in these three materials also differed. These results suggest that MsNST1 affects lignin synthesis in alfalfa. These findings provide a genetic basis and abundant gene resources for further study of the molecular mechanisms of lignin synthesis, laying a foundation for low-lignin alfalfa breeding research.