Grassland soil microorganisms are key elements in maintaining the nutrient cycle function of ecosystems, and are sensitive indicators of changes in grassland ecosystems. Based on the study of soil microbial community composition and soil physicochemical properties under four utilization modes, namely enclosure, mowing, grazing, and reclamation in the Hulunbuir grassland, the effects of grassland utilization mode on grassland microbial communities were expounded. The results showed that: 1) After grassland reclamation, the soil total carbon (TC) and nitrogen (TN) content decreased by 41.45% and 45.08%, respectively, whereas the electrical conductivity (EC) and available phosphorus (AP) content increased by 371.93% and 139.93%, respectively, and the phospholipid fatty acid (PLFA) content of the farmland microbial community was limited by carbon and nitrogen. 2) Compared with enclosed grassland, grazing grassland, and farmland, mowing significantly increased the PLFA of soil bacteria, fungi, actinomycetes, gram-positive bacteria (G+), gram-negative bacteria (G−), and microbial communities. 3) According to the comprehensive analysis of the four grassland utilization modes, TC and TN were positively correlated with PLFA content of soil bacteria, fungi, actinomycetes, G+, G−, and other microbial communities, while AP, pH, and EC were negatively correlated. Therefore, grassland reclamation resulted in soil carbon and nitrogen nutrient loss for farmland and further reduced the amount of PLFA in the microbial community. Considering the reduction in soil nutrients and PLFA in microbial communities, it is not recommended that Hulunbuir grasslands be reclaimed as farmland.
In order to clarify the response of temperate desert grassland community to enclosure and soil environment, field sampling and laboratory experiments were combined, and the effects of different grazing prohibition years (unforbidden grazing and grazing prohibition for 5 and 9 years) on grassland community characteristics and soil nutrient characteristics in spring and autumn pastures were studied to provide a theoretical basis for rational utilization and management of spring and autumn pastures. The results showed that with the increase in grazing prohibition years, the average height, coverage and biomass of grassland community were significantly higher than those of non-grazing prohibition grassland community (P < 0.05). The average density of grassland community without grazing prohibition was significantly higher than that of grassland community with grazing prohibition for 5 and 9 years (P < 0.05). The Simpson and Shannon Wiener diversity indexes of different grazing prohibition years showed that grazing prohibition for 9 years > grazing prohibition for 5 years > no grazing prohibition, but the spatial distribution of grassland community in grazing prohibition for 5 years was more uniform, while the species richness of grassland community in grazing prohibition for 9 years was higher. Canonical correspondence analysis(CCA) showed that the main soil factor affecting the growth characteristics of grassland vegetation in different grazing prohibition years was soil water content (39.7%), monitored by soil pH (9.6%). Enclosure grazing prohibition can thus significantly improve grassland productivity and promote species diversity. It is an effective measure to address the restoration of degraded temperate grassland community.
The Mongolian Plateau is located in an arid and semi-arid region with fragile ecosystems and frequent drought disasters. In this case, exploring the response of the grassland cover to drought can provide a scientific basis for improving ecological environment as well as disaster prevention and mitigation. On the basis of MODIS remote sensing data and vegetation cover measurement data from 2001 to 2020, this thesis analyzed the change of grassland cover, drought distribution, and the correlation between them in the grassland area of Mongolian Plateau by adopting methods such as the decision tree classification method, the temperature condition index method, and the correlation analysis method. The results revealed the following: 1) From 2001 to 2020, the grassland area in the Mongolian Plateau showed an overall increasing trend. From 2001 to 2007, the dominant grassland coverage was from 40% to 60% and from 20% to 40%; after 2017, the dominant grassland coverage was from 60% to 80% and from 40% to 60%. Overall, there was a tendency of shift towards high coverage. Among the grasslands with different coverage, the transfer-in and transfer-out areas of the grasslands from 40% to 60% and from 20% to 40% were very large, with strong fluctuations and poor stability. 2) During these 20 years, 2001, 2007, 2010, 2017 and 2019 were the drought years in the study area, and the drought conditions in 2003, 2013, 2018, and 2020 were relatively moderate. The proportion of the medium-drought area could represent the overall drought situation in the study area to some extent. 3) As a whole, the reduction of grassland cover in the grassland area of the Mongolian plateau was positively correlated with the drought climate. The sensitivity of the grassland coverage with different vegetation types to the drought was ranked as follows: the typical grassland was larger than the desert grassland, which was larger than the meadow grassland; the grassland coverage from 20% to 60% responded more significantly to the drought.
Vegetation coverage is an objective index and an important parameter that reflects the basic extent of vegetation. In this study, we evaluated and analyzed the effectiveness of eight different visible-light-based vegetation indices for estimating the vegetation cover of different grassland types. Upon comparison of accuracy of these vegetation indices, we found that these vegetation indices were less effective in estimating the vegetation cover of desert grasslands. Therefore, we have proposed a desert vegetation index (DVI) to estimate the vegetation cover of desert grasslands. The effects of different vegetation indices on the vegetation cover estimation of different grassland types were evaluated, and the changes in the threshold values of different grassland types were analyzed. The results showed that: 1) The common vegetation indices could estimate the vegetation coverage in meadow grasslands and typical grasslands with a high accuracy (accuracy > 90%, F1 > 0.9). The ExG (excess green index) was the best in estimating the vegetation coverage in meadow grasslands (accuracy > 93%, F1 > 0.95), and there was no significant difference among the estimation power of vegetation indices when estimating the coverage in typical grasslands. However, the common vegetation indices exhibited low accuracy of vegetation coverage estimation (F1 ≤ 0.6) in desert grasslands. 2) The DVI proposed in this study has a high estimation accuracy of vegetation coverage in desert grasslands (accuracy > 93%, F1 score reached 0.71), which can effectively compensate for the defects of the above-mentioned vegetation indices. 3) The thresholds of GLI (green leaf index) and CIVE (color index of vegetation extraction) were the least sensitive to grassland types; the thresholds of ExG, ExGR (excess green minus excess red index), VEG (vegetative index), and WI (woebbecke index) were less sensitive to the effects of meadow grasslands and typical grasslands, but more sensitive to the effect of desert grasslands; and COM (combination index) and Lab (lab index) were the most sensitive to all the grassland types considered in this study.
The greenhouse pot experiment was used to study the effects of the arbuscular mycorrhizal fungus (AMF) Funneliformis mosseae (FM) and three different planting patterns on growth parameters, mineral nutrient absorption, and inter-species competition of white clover (Trifolium repens) and ryegrass (Lolium perenne) on iron tailings. This study aimed to identify a type of cultivation mode that could not only increase plant colonization but also improve the introduction of pioneer plants in tailings and to provide a theoretical and application basis for plant restoration on iron tailing wasteland. The results showed that FM could establish a symbiotic with the two other plant species and had a higher rhizosphere mycorrhizal infection rate under mixed planting. The rhizosphere mycorrhizal infection rate of mixed planting white clover was the highest, with an average of 47.9%. Inoculation with FM significantly increased the phosphorus concentrations in white clover (168% ~ 357%) (P < 0.05) and the phosphorus concentrations in ryegrass in mixed planting (10.5%) (P < 0.05) as well as the biomass of white clover (by approximately 5 ~ 7 times) (P < 0.05) and ryegrass in mixed mode (1.9 times) (P < 0.05). In mixed planting, plant iron concentrations were significantly higher than that in single species. FM inoculation significantly decreased the iron concentrations in shoots of the white clover (P < 0.05), but the iron concentration in their roots increased. FM inoculation increased the iron absorption of white clover and ryegrass under the single mode and significantly decreased the iron absorption of ryegrass under the mixed mode (P < 0.05). In the mixed planting mode, the two plants had higher iron absorption efficiency, FM inoculation significantly increased the iron absorption efficiency of white clover (P < 0.05) and decreased that of ryegrass. The mixed planting mode significantly increased the zinc concentrations and decreased the copper concentrations of white clover. FM inoculation significantly decreased the manganese concentrations of two plants and significantly increased the copper concentrations of white clover. The white clover and ryegrass hybrid system has a land equivalent ratio greater than 1, which has a mixed advantage. The interspecific competitive ability of ryegrass compared with white clover was greater than 0, indicating a competitive advantage. Mycorrhizal fungi may improve the competitive ability of white clover. Mixed planting can, therefore, significantly promote the growth of ryegrass, whereas inoculation with FM can enhance the competitiveness of white clover. AMFs have great potential for use with pioneer plants to adapt to the complex adversity of iron tailings and to restore tailings pioneer vegetation.
In this study, we examined the ability of three exogenous substances to alleviate salt stress in the creeping bentgrass (Agrostis stolonifera) cultivar ‘L-93’. A pot experiment was conducted to investigate the effects of potassium sulfate (K2SO4), ascorbic acid (AsA), and glycine betaine (GB) on the turf quality (TQ), relative water content (RWC), electrolyte leakage (EL), malonaldehyde (MDA) and ion contents, and antioxidant enzyme activity of the creeping bentgrass under salt stress conditions. Salt stress significantly reduced the TQ, RWC, and antioxidant enzyme activity of ‘L-93’ (P < 0.05) and significantly increased the EL and MDA contents (P < 0.05), resulting in an ion imbalance. However, the application of K2SO4 and AsA alleviated the negative effects of salt stress, significantly increasing RWC (P < 0.05), significantly reducing EL and the accumulation of Na+ in leaves (P < 0.05), and increasing the K+ content of leaves, thereby reducing the Na+/K+ imbalance. In addition, exogenous spraying of K2SO4 and AsA improved the catalase (CAT) activity in and salt tolerance of the creeping bentgrass, while also enhancing its antioxidant capacity, under salt stress. Exogenous GB application significantly increased CAT activity and decreased Na+/K+ values in creeping bentgrass leaves (P < 0.05) but had no significant effect on TQ or MDA content (P > 0.05); the overall effect was inferior to that of K2SO4 and AsA.
Grassland degradation due to the impacts of overgrazing and climate change is a common phenomenon. Therefore, grassland surveys have become an effective strategy for understanding the degree of grassland degradation. In the present study, total grass yield, edible grass yield, and vegetation coverage were selected as the evaluation indices of grassland degradation in Gansu Province, determined based the data collected during two surveys: the first survey in the 1980s and the second from 2014 to 2017. According to the national standards of grassland degradation, combined with the expert scoring method, we used inverse distance weighted interpolation to evaluate the degradation indices and explore the spatial distribution of each degradation grade in the study area. The area of the degraded grassland was 1.79 × 107 ha, accounting for 69.65% of the total grassland area in Gansu Province. Of this, 23.81% was slightly degraded, 47.27% moderately degraded, and 28.92% severely degraded. The most degraded grassland types were alpine desert steppe and alpine steppe, whereas the least degraded grassland types were mountain meadow meadow and temperate desert steppe. These findings advance our understanding of the current status of grassland degradation in Gansu Province.
In this study, Greek oregano (Origanum vulgare ssp. hirtum) seeds were exposed to 60Co-γ -ray radiation to generate a mutant population for mutant screening with elite traits. The results showed that, with increasing dosage of radiation, the germination rate and germination potential of oregano seeds significantly decreased, and exposure to radiation dosages of 400 Gy or higher led to radical growth stagnation with seedling non-survival. A total of 8 170 M1 mutants were obtained at radiation dosages of 100～200 Gy. In comparison with the phenotypic traits of untreated control plants in the field, a group of mutants with tall plant height, short internode length, multiple shoot numbers, large leaf size, and varied leaf and flower colors were obtained, thus providing a foundation for breeding new, high-yield, and high-quality oregano varieties.
To explore the effect of planting density on the growth and quality of Eremopyrum orientale in northern Xinjiang, a potting experiment was used to set up three planting densities of 3, 6 and 10 plants per pot, about 100, 200 and 335 plant·m−2, respectively, and the plant height, leaf length, leaf width, stem thickness, tillering number, biomass, crude protein, neutral detergent fiber and acid detergent fiber under each planting density were determined, and the difference analysis was carried out. The results showed that the plant height, leaf length, leaf width and population biomass of E. orientale increased with the increase of planting density, and the planting density had no significant effect on stem thickness, tillering number, single plant biomass and root-to-shoot ratio (P > 0.05), and the contents of crude protein, neutral detergent fiber, and acid detergent fiber of E. orientale increased with the increase of planting density. Considering the population biomass and forage quality, E. orientale grown under the planting density of 10 plants per pot (335 plant·m−2) can play a greater role in spring supplementary feeding.
Chloris virgata is a naturally occurring alkali-tolerant halophyte. To explore the physiological mechanism underlying the alkali tolerance of C. virgata, we used 150 mmol·L−1 alkaline salt solution ( NaHCO3 ꞉ Na2CO3 = 9 ꞉ 1) to treat C. virgata seedlings for one month. After the alkali stress treatment, we detected different mineral elements (Na, K, Ca, Mg, P, and Fe) and calculated the distribution of each mineral element among different organs (shoots, spikes, and roots). We also observed changes in leaf photosynthesis. The results indicated that long-term alkali stress strongly inhibited leaf photosynthesis and reduced the contents of K, Ca, P, and Mg in different organs. Analysis of the distribution of each element among the three organs showed that the relative contents of Na, K, Ca, Mg, and Fe in shoots were significantly higher than those in spikes and roots under alkali stress (P < 0.05). However, P still largely accumulated in the spike under alkali stress, and the contribution of P to the total element in the spike reached 49.80% under the control condition and 50.02% under the alkali stress condition. Analysis of the contribution percentage of each element to the total showed that K content was much higher than that of other elements in all organs, followed by Ca and P. Under alkali stress conditions, Na was extensively accumulated in all three organs, especially in shoots, where Na accumulation was enhanced from 0.707% to 28.397% by alkali stress. The shoot Na content of the alkali stress treatment was 28.399-fold that of the control treatment. However, under alkaline stress conditions, the spikes of C. virgata maintained a high K content, which supports the normal growth of the spike. In conclusion, C. virgata can complete its life cycle under long-term alkali stress conditions because of its strong ability to regulate Na. C. virgata protects young spikes under long-term alkali stress by enhancing the accumulation of Na in roots and shoots and lowering the accumulation of Na in the spike. C. virgata can also maintain a normal level of P to preserve normal physiological metabolism and relieve the damage caused by alkali stress.
Viola philippica has two types of fruits: chasmogamous (CH) flowers and cleistogamous (CL) flowers. In addition, V. philippica has the characteristics of “sustained results” and “continuous seed dispersal”, and fruits of different maturity can be observed at the same time. Based on the observation of the fruit and seed morphology of V. philippica, the development process of the two types of fruits and the morphological germination characteristics of seeds at different development periods were compared. The results showed that: 1) The development time of CH fruit (24 ~ 29 days) was longer than that of CL fruit (16 days). 2) The CH and CL fruits had the same characteristics of development period and cracking dispersion. According to the angle between the fruit and fruit stalk and the morphological characteristics of the fruit, the maturity of the fruit (seed) is divided into 8 levels. With increasing development time, the length and width of CH and CL fruits and seeds showed an increasing trend, and the length and width of CH fruits and seeds were larger than those of CL fruits and seeds in each period. By contrast, the thousand-grain weight and water content of seeds were negatively correlated at different developmental stages; if the thousand-grain weight increased, the water content decreased. 3) When the angle between fruit and stalk was greater than 90° (after Ⅳ period), the thousand grain weight and water content of CH and CL seeds were fundamentally stable (about 1.00 ~ 1.15 g, 5% ~ 13%). The germination characteristics of the two seeds differed during different developmental periods. Under the condition of low maturity (before period IV), the germination rate, germination index, and vigor index of the two seeds were significantly increased (P < 0.05). After period Ⅳ, the germination indexes of seeds in each stage decreased after reaching their highest value, but the difference was not significant (P > 0.05). Thereafter, the germination percentage of seeds reached more than 80%, and the vigor index remained at a high level (400.00 ~ 550.00). In conclusion, an angle between fruit and stalk greater than 90° can be used as the standard for fruit harvesting, which is characterized by full CH and CL seeds, low water content, high germination percentage, and strong seed vigor.
Using Carex subpediformis as the experimental material, potted plants were used to study the effects of different concentrations of NaCl stress on their growth, development, and physiological index changes, and the salt tolerance threshold was calculated. The results showed that with increasing NaCl concentration, the plant height and crown width of C. subpediformis decreased, as did the dry weight content of the leaves. Under salt stress conditions, the plasma membrane permeability and malondialdehyde content of C. subpediformis leaves increased, changes in superoxide dismutase and peroxidase activities first increased and then decreased, free proline and soluble sugar content first increased and then decreased, and free proline content was significantly different between treatments (P < 0.05). The chlorophyll content of C. subpediformis first increased and then decreased. However, there was no significant difference in the chlorophyll a/b values between the treatments (P > 0.05). Taking a 50% decrease in the biomass of C. subpediformis as the standard, a regression equation was established to obtain the salt tolerance threshold of C. subpediformis at 169 mmol·L−1. In conclusion, C. subpediformis is considered to have a certain tolerance to salt stress and can grow normally in a certain range of salt-stress environments. These results provide data support for follow-up studies on the salt tolerance mechanisms of C. subpediformis.
To fully exploit the abundant water and heat resources and establish an annual production system for forage grass in Sichuan Province, the yield and quality of forage grass under different planting patterns of silage maize (Zea mays) and forage oat (Avena sativa) were studied. The growth period of forage oat and silage maize was shortened with the delay in sowing date. The comprehensive performance of late autumn ‘Linna’ was good, which was associated with silage maize in rotation. When the sowing date of silage maize was May 21, 2019, ‘Aoyu 3628’ showed the best comprehensive performance and could be used as the first forage in the rotation pattern of two-season silage maize. When the sowing date was August 21, 2019, ‘Yayu 158’ showed the best comprehensive performance and could be used as the second forage in the rotation pattern of two-season silage maize. The analysis of forage yield and quality with single cropping and rotation of forage oat and silage maize revealed that the annual growth period of “silage maize ‘Aoyu 3628’ → silage maize ‘Yayu 158’→ forage oat ‘Linna’ ” was up to 339 days; the annual forage yield was 48 905.15 kg·ha−1; and the crude protein yield was 5 388.35 kg·ha−1, all of which were significantly higher than the values obtained in other planting patterns. Therefore, this planting pattern presents great potential for popularization and implementation.
This study aimed to explore the effects of different levels of silicon fertilizer on lodging resistance traits and yield of oats (Avena sativa) in alpine region. Two cultivars of oat (‘Qingyin No. 2’ and ‘QYJ507’) were used as the study materials. Four fertilizing rate (0, 45, 90, and 135 kg·ha−1) of silicon were applied in a split-plot experimental design to reveal the effects of silicon application on lodging resistance traits and seed yield of oats. The results showed that the root diameter, root volume, fresh and dry weight of roots, stem thickness, and stalk wall thickness of the second and third stem nodes of oats increased first and then decreased with the increase in silicon fertilizer application. The root length, root diameter, root volume, fresh and dry weight of root, stem diameter, and stem wall thickness were increased, the lengths of the second and third internodes at the base were shortened, and the mechanical properties of the stalk were enhanced in ‘Qingyin No. 2’ and ‘QYJ507’ under 45 and 90 kg·ha−1 treatments, respectively. Under the same treatments, the highest seed yields of 2 323.08 and 2 038.43 kg·ha−1 were obtained for ‘Qingyin No. 2’ and ‘QYJ507’, respectively. Therefore, the application of silicon fertilizer can improve the lodging resistance and seed yield of oats in the alpine region, but the silicon fertilizing rate should depend on the characteristics of different varieties.
Fungal diseases are a serious threat to buckwheat (Fagopyrum esculentum), affecting its yield and quality. This study aimed to determine the role of fungicides in preventing the most prevalent diseases of buckwheat in Gansu Province. For this purpose, the inhibitory effect of seven types of high-efficiency and low-toxicity fungicides on the mycelial growth of six targeted pathogens was studied. The results showed that 80% mancozeb (EC50: 0.030 4 mg·L−1), 80% carbendazim (EC50: 0.049 0 mg·L−1), 80% mancozeb (EC50: 0.052 5 mg·L−1), 20% difenoconazole·prochloraz (EC50: 0.041 8 mg·L−1), 40% pyrimethanil (EC50: 0.068 4 mg·L−1), and 80% mancozeb (EC50: 0.010 5 mg·L−1) had the strongest inhibitory effect on mycelial growth of pathogens such as Alternaria alternata, Botrytis cinerea, Botrytis polygoni, Bipolaris zeae, Hedymella rhei, and Stemphylium vesicarium, respectively. In addition, 80% mancozeb showed the highest inhibitory effect against five pathogens: Alternaria alternata, Botrytis cinerea, Botrytis polygoni, Didymella rhei, and Stemphylium vesicarium. This study provides comprehensive information on types of control agents and preventive fungicides as well as reference values for disease prevention and green buckwheat production.
In this study, we investigated the effects of neutral detergent fiber (NDF) to starch ratios on the development of the digestive tract of lambs. Sixty male Hu lambs with similar birth weights [(3.14 ± 0.05) kg] were randomly divided into three groups with 20 lambs in each group. At 10 days of age, the lambs were supplemented with NDF to starch ratios of 0.50 (group Ⅰ), 0.70 (group Ⅱ) and 1.00 (group Ⅲ). They were weaned at 35 days of age and slaughtered at 56 days of age. Following results were obtained: 1) The height of the rumen papilla, the height and width of the primary crease of the reticulum, and the thickness of the muscular layer in group Ⅱ were significantly higher than those in groups Ⅰ and Ⅲ (P < 0.05), while the height of the rumen papilla in group Ⅲ was significantly higher than that in group Ⅰ (P < 0.01). 2) The crypt depth of the duodenum and ileum in group Ⅱ was significantly lower whereas the thickness of the muscular layer was significantly higher than that observed in groups Ⅰ and Ⅲ (P < 0.05). The crypt depth of the duodenum in group Ⅲ was significantly lower than that in group Ⅰ (P < 0.01). In conclusion, starting diets with an NDF to starch ratio of 0.70 is beneficial for the digestive tract development of lambs. The results of this study can provide a reference for the preparation of starter diets for lambs.
The present study aimed to develop a method for culturing mononucleosis nematodes (MONO- nematodes) using the symbiotic bacteria (SB) of these nematodes, providing a basis for examining nematode pathogenicity and collecting infective juveniles (IJs). SB were isolated from two EPN strains collected from the Gansu Province: Steinernema kraussei, which is highly resistant to low-humidity stress, and Heterorhabditis brevicaudis, which is sensitive to low-humidity stress. The isolated bacteria were purified and cultured on NBTB. Subsequently, single colonies of SB were transferred to LB medium. Thereafter, the SB were incubated on LB medium with a gravid nematode female, which was collected from the body of an infected wax worm, and cultured to collect IJs. Therefore, the SB of S. kraussei 0657L and H. brevicaudis 0641TY could be isolated using the method described here and IJs could be collected through culture with these SB. The proposed protocol can serve as a simple, rapid, and accurate method to collect IJs of MONO- nematodesdirectly isolating the gravid nematode females from infected wax worms and incubating them with purified SB.
This study aimed to investigate the effects of silage fermentation promoters on the nutritional quality of whole-plant corn silage at different harvest stages. In 2018, ‘Yu silage 23’ was used as the test material, and three treatments (control, Sila-Max, and Sila-Mix) were set at 1/2, 2/3, and 3/4 milk-line periods, repectively. After 60 days of silage, openbag sensory evaluation and sampling were conducted to determine nutritional quality. The results showed that the silage fermentation promoter had no significant effect on the sensory evaluation of the whole plant silage corn (P > 0.05), which significantly affected ammonia nitrogen (NH3-N), lactic acid (LA), acetic acid (AA), dry matter recovery (DMR), dry matter (DM), crude protein (CP), and water-soluble carbohydrate (WSC) content (P < 0.01), as well as the pH, butyric acid (BA), and starch (ST) content (P < 0.05). The delayed harvest period had a significant impact on the whole plant corn silage LA, AA, BA, DMR, DM, CP, ether extract (EE), crude ash (Ash), neutral detergent fiber (NDF), acid detergent fiber (ADF), ST, WSC, 48 h in vitro dry matter digestibility (IVDMD48 h), 48 h in vitro neutral detergent fiber digestibility (IVNDFD48 h), and total digestible nutrients (TDN) (P < 0.01), as well as the pH (P < 0.05). The gray correlation results show that the stage when the milk-line is at 2/3 is suitable for harvesting, and the silage fermentation promoter Sila-MIX is suitable for promotion and use in production practice.
To select high-quality silage oat (Avena sativa) suitable for planting in the alpine pastures of Diqing, 11 cultivars were tested for growth period and conventional silage in the Pudatsuo National Park, Diqing Tibetan Autonomous Prefecture, Yunnan Province. Specifically, the fermentation quality and nutritional composition of silage were assessed after 60 days. Differences in nutritional quality before and after silage were compared to solve the problem of forage deficiency in the alpine areas of northwestern Yunnan. The following results were noted. 1) The 11 oat cultivars tested completed the reproductive period in the alpine pastures of Diqing, reaching the highest hay yield of 17 060.93 kg·ha−1. 2) After silage, the total sensory evaluation score exceeded 16; eight oat cultivars showed better fermentation quality; and the highest lactic acid content was noted in ‘ESK’ (P < 0.05). 3) After silage, ‘LAMPTON’ showed the highest dry matter content; ‘Baler II’ showed the highest crude protein content (P < 0.05); and fiber content decreased in all cultivars. Comprehensive analysis of the nutritional and fermentation quality of silage from eight oat cultivars revealed that ‘Baler II’ (r = 0.808 5), ‘ESK’ (r = 0.749 5), and ‘Baler’ (r = 0.737 3) showed better silage quality, warranting promotion and cultivation as silage oat in the alpine pastures of Diqing.
The steady advancement of the “Changing Grain to Forage” policy has far-reaching effects on the high-quality development of animal husbandry in China. This study explored changes in the efficiency of beef cattle breeding under the “Changing Grain to Forage” policy based on production monitoring panel data for 22 pilot areas in eight provinces (Anhui, Hebei, Henan, Liaoning, Heilongjiang, Inner Mongolia, Gansu, and Yunnan). Data were combined with a cost efficiency model and the Malmquist index to calculate changes in the cost efficiency of beef cattle breeding between 2013 and 2019. Since the implementation of the policy, the cost of beef cattle feed in the pilot areas has remained relatively stable, particularly compared with the significant increase in costs in non-pilot areas. Over the study period, the proportion of roughage increased by 7.3 percentage points, the proportion of concentrated feed decreased, and the feed structure was improved to some extent compared with that before implementation of the policy. The cost efficiency of beef cattle breeding in most provinces improved, to varying degrees, but the unreasonable allocation of production input materials still remains an issue. Compared with non-pilot areas, the price of beef cattle breeding input factors in the pilot areas improved, and implementation of the policy played a positive role in improving the “distortion” degree of input factor prices. Under an assumption of labor homogeneity, beef cattle breeding in the pilot area had the highest labor input redundancy. The results indicate that expansion of the “Grain to Forage” policy should continue in combination with efforts to strengthen technical guidance, combine planting and breeding, and establish planting based on breeding to eliminate redundancies.
Based on the emphasis of higher education on the concept of “take undergraduate education as basic of education, return to common sense, return to original duty, return to original intention, and return to original dream”, the positioning of experiment stations in universities should pay more attention to the practical teaching function of undergraduates, apart from the positioning of scientific research. In the present study, the Qingyang Grassland Agricultural Science Experiment Station of Lanzhou University was considered as the case study to analyze the current situation of connecting the experimental station with undergraduate practice teaching, and several management strategies for strengthening undergraduate practice teaching in field stations were also framed. Qingyang Station has a good infrastructure and scientific research foundation. By taking advantage of the natural resources around the experimental field, such as Ziwuling and other surrounding enterprises, it has carried out many years of practical teaching activities and accumulated rich experiences. We provided the following suggestions for improving practice teaching: 1) highlight the location feature and discipline characteristics in the station layout design. 2) expand the opening and communication and promote interdisciplinary integration. 3) make full use of the stations and surrounding resources, and strengthen the construction of field observation platforms and practice bases. 4) cooperate with the government and enterprises, to establish long-term and stable school–enterprise cooperation and practice bases. This study can provide guidance for field station construction and undergraduate practice teaching in colleges and universities.