This research aimed to clarify the effects of fungicides applied in Medicago sativa production on the safety of an important pollinating insect, the honeybee (Apis mellifera), One-day-old adult honeybees were fed a diet containing dimetachlone, prochloraz, iprodione, at a range of concentrations (diluted with water 1:500, 1:1000, 1:1500, 1:2000 and 1:2500) or no fungicide (Control). Subsequently, the activities of three protective enzymes, superoxide dismutase (SOD), guaiacol peroxidase (POD), catalase (CAT), and three detoxifying enzymes, carboxylesterase (CarE), glutathione S-transferase (GST), cytochrome P450 (P450) in the honeybees were measured. It was found that different concentrations of all the three fungicides could induce increased activities of SOD and POD in the honeybees. In particular, treatment with prochloraz solution at the 1:1500 dilution (0.17 mg·L^-1) induced a 1.82-fold SOD activity and a 5.40-fold POD activity compared to the Control treatment. All three fungicides showed low concentration induction and high concentration inhibition of CAT, CarE and GST activities, and showed inhibition (prochloraz) or induction (dimetachlone and iprodione) of P450 activity. With extended treatment time, the 1:1000 dilution of all three fungicides (0.40, 0.25 and 0.50 mg·L^-1 of dimetachlone, prochloraz, and iprodione, respectively) showed an overall induction effect on the activities of the three protective enzymes in Italian bees, but a variable effect on the activities of detoxifying enzymes. Specifically, dimetachlone initially increased the activities of the three protective enzymes and then inhibited activity after 6 h; iprodione induced P450 activity at all times, but inhibited the activities of CarE and GST in the first 12 h, then induced their activity thereafter; prochloraz elicited a gradual decrease in P450 activity with time, but initially induced then later inhibited the activities of CarE and GST. The results indicate that Italian bees can reduce the negative effects of fungicides by regulating the activities of protective and detoxifying enzymes in their bodies, but the fungicides have an impact on the normal physiology and metabolism of bees, even so. Therefore, care should be taken when applying fungicides to protect bees and ensure their safety while pollinating agricultural crops.

The objective of this study was to evaluate the effects drinking water temperature on production performance, apparent digestibility of nutrients and blood biochemical parameters in fattening sheep in winter, and rumen structure was also observed using a microscope. Information on the ideal temperature of drinking water for fattening sheep might well lead to improved production efficiencies through mechanisms such as alleviation of cold stress. A flock of 135 healthy fattening sheep with similar weight were randomly assigned into three groups, with drinking water supplied at 2, 8 and 20 ℃ for the respective groups. Each treatment contained three pens (15 sheep·pen^-1). The experiment duration was 28 days. It was found that: 1) Compared with the 2 ℃ group, the 8 and 20 ℃ groups had increased daily water consumption (P<0.05). Although there was no statistical difference (P>0.05) in daily feed intake and daily gain between any of the groups, the feed conversion efficiency in the 20 ℃ group was higher than that in 2 ℃ group (P<0.05). 2) There was a difference (P<0.01) between groups in the serum glucose (GLU) contents. The GLU content in 8 and 20 ℃ groups was 1.39 and 1.14 times higher, respectively, than that in the 2 ℃ group, and the 20 ℃ group had decreased the serum cholesterol (P<0.05). The serum urea nitrogen, total protein and serum hormone (triiodothyronine, thyroxine and growth hormone) contents did not differ between groups (P>0.05). 3) The length, width, and surface area of rumen papilla in the 20 ℃ group were increased (P<0.05) compared with the 2 and 8 ℃ groups. The group drinking water at 20 ℃ had reduced rumen muscle layer thickness (P<0.05) and increased submucosal thickness (P<0.05). However, there was no difference (P>0.05) in thickness of mucosal epithelium among groups. 4) With increase in drinking water temperature, the apparent digestibility of crude fat, neutral detergent fiber (NDF) and phosphorus (P) increased (P<0.05), especially P and NDF, while the digestibility of other nutrients did not differ between treatment groups (P>0.05). The results showed that drinking warm water improved the feed conversion efficiency of fattening sheep. In addition, drinking warm water may improve rumen function and promote the digestion and absorption of nutrients.

The effect of nitrogen fertilizer application rate on chlorophyll fluorescence characteristics and dry matter accumulation of switchgrass (Panicum virgatum) is of great significance for the improvement of light use efficiency and biomass yield of switchgrass in saline-alkali land. In this research, the patterns of variation in chlorophyll fluorescence parameters and dry matter accumulation in switchgrass were studied in field conditions with a range of nitrogen application treatments: no nitrogen (0 kg·ha^-1, N₀), low nitrogen application (60 kg·ha^-1, N₆₀), medium nitrogen application (120 kg·ha^-1, N₁₂₀) and high nitrogen application (240 kg·ha^-1, N₂₄₀), and the comprehensive effect of nitrogen application on chlorophyll fluorescence and dry matter accumulation in switchgrass was evaluated using a multivariate Grey relational analysis procedure. It was found that: under N₆₀, N₁₂₀ and N₂₄₀ treatments, the PSⅡ maximum photochemical efficiency (F_v/F_m), PSⅡ actual photochemical quantum efficiency (Φ_PSⅡ), potential activity (F_v/F_o), photochemical quenching (qP), non photochemical quenching (NPQ) and biomass yield were significantly higher, and the heat dissipation of quantum ratio (F_o/F_m) was significantly lower than for the N₀ treatment during the flowering and seed maturation stages of switchgrass development. During the flowering period of switchgrass, the PSⅡ potential activity (F_v/F_o) was initially increased and subsequently decreased across the range of nitrogen application rates, with a maximum observed value of 3.13 at N₁₂₀ (increased 16.26% compared with N₀). The effect of nitrogen application rate on dry matter accumulation differed between the crop growth stages. Dry matter accumulation was high during jointing and booting periods, reached its maximum at the seed filling stage, and decreased slightly thereafter. The maximum observed dry matter accumulation (378.13 g·hole^-1) occurred under the N₂₄₀ treatment during the post-flowering stage and was, respectively, 24.33%, 20.09% and 7.24% higher than that of the N₀, N₆₀ and N₁₂₀ treatments. Grey relational analysis showed that the association between the weighted correlation index and the ideal fertilization level was the highest under the N₂₄₀ treatment. In summary, the N₂₄₀ treatment in this study in the Yinbei saline-alkali area of Ningxia optimized the photochemical activity of PSⅡ and dry matter accumulation of switchgrass.

This research investigated the effect of lactic acid bacteria (LAB) preparations on microbial population counts and silage quality of whole maize silage during fermentation and on aerobic exposure after fermentation. The aim was to test if inoculation with LAB preparations can improve silage quality and aerobic stability. Three different LAB preparations [Homofermentative (Homo), Heterofermentative (Hetero), combined Homo+Hetero] were added to whole maize during ensiling. A blank control treatment was also included. Data on microbial population count, fermentation quality and nutrient contents of silage were evaluated during fermentation at 3, 7, 15, and 30 days after ensiling, and on completion of fermentation, after 1, 3, 7, 15 and 30 days of aerobic exposure. It was found that both during maize silage fermentation and during subsequent aerobic exposure, the LAB population counts, the lactic and acetic acid concentrations were significantly increased compared with the blank control treatment, while the numbers of aerobic bacteria, yeasts and molds and crude protein loss were significantly reduced and the concentrations of NH₃-N and the pH were obviously reduced by addition of the three LAB preparations. These results indicate that LAB preparations improve maize silage nutritional quality and inhibit secondary fermentation after aerobic exposure. The combination treatment Homo+Hetero performed best, and Homo performed better than Hetero.

This study investigated the relationship between soil moisture and vegetation cover in alpine steppe meadow in the Qilian Mountains with the aim of improving the precision of remote sensing estimates of soil moisture and vegetation cover. Six sample areas with different stocking rates of Cervus elaphus kansuensis (1.00, 1.45, 2.45, 3.45, 4.85, 6.90 AUM·ha^-1) in were set up, AUM means animal unit. Through comparing data from monthly field measurement of vegetation cover and soil moisture and SPOT-TM images combining Landsat5 multispectral images and SPOT2 panchromatic images, we analyzed the relationship between soil moisture, vegetation cover and normalized difference vegetation index (NDVI) and quantitatively explored the dynamics of seasonal change in vegetation cover and soil moisture in the sample areas in the Qilian Mountain alpine steppe. Except for Achnatherum inebrians, Convolvulus ammannii and Stragalus leucocephalus, the response of population cover to surface soil moisture was relatively sensitive, with the population cover of species inversely proportional to soil moisture in the range between c. 5% and c. 25%. The response of plant community cover to surface soil moisture was also relatively sensitive. In the soil moisture range from 10.0% to 1.1%, the community cover increased in the inverse proportional function. The results are highly relevant to remote sensing monitoring of the drought resistance and water use efficiency of plant species, populations and communities in arid and semi-arid steppe grassland, and provide scientific data for vegetation and soil moisture management in steppe grasslands.

This research investigated the effects of fertilizer application and soil-plastic mulching on soil water storage, periodic evapotranspiration (ET), plant development, yield and water use efficiency (WUE) of Tartary buckwheat crops grown in a semiarid rain-fed area, in order to identify cultivation techniques that enhance crop drought resistance and efficient resource utilization. A field experiment comprising three treatments was conducted from 2015 to 2017 at Dingxi Experimental Station of Gansu Academy of Agricultural Sciences. The three treatments were: traditional planting without fertilization application (TNF), whole field soil-plastic mulching without fertilization application (MNF), and whole field soil-plastic mulching with fertilization application (MF). The soil water content for the 0-300 cm soil depth, crop dry matter, leaf area index and yield of Tartary buckwheat were recorded. The soil water storage, periodic measurements of ET, harvest index, rainwater use efficiency (RUE) and water use efficiency (WUE) were calculated, to determine the effects of fertilizer application and soil plastic mulching and bunch seeding on water utilization and yield. It was found that MF increased soil water storage by 18.9-42.4 mm in the 0-140 cm soil layer during the seedling stage, and the ET in the pre-flowering period, as compared with TNF and MNF. Compared to TNF and MNF, respectively, MF increased the dry matter quality at maturity by an average of 96.3% and 3.7%, the leaf area index by 123.7% and 7.6%, the number of ears by 9.3% and 3.9%, the grain weight per plant by 139.2% and 12.1%, the grain plumpness by 14.5% and 4.4%, and reduced the ear height by 34.0% and 26.8%. Compared to TNF, MF significantly promoted the population-level statistics of Tartary buckwheat, with a yield increase of 33.6%-130.4%, a biomass increase of 62.8%-182.5%, an enhancement of WUE of 34.5%-106.4%, and these effects were more pronounced in dry seasons. Therefore, the cultivation practice comprising whole-field soil plastic mulching with fertilizer application improves the yield and WUE of Tartary buckwheat, can be recommended as a suitable planting mode for drought amelioration and yield increase of Tartary buckwheat in the semi-arid area of the northwest Loess Plateau.

This research investigated seed germination and seedling growth of four species of bioenergy grass (Pennisetum americanum×Pennisetum purpureum, Pennisetum purpureum, Pennisetum hydridum and Sorghum sudanense), grown on electrolytic manganese residue (control) or electrolytic manganese residue after adding one of three amendments (5% diatomite, 5% charcoal or 2.5% charcoal+2.5% diatomite). Germination percentage for the four bioenergy grasses ranked: P. purpureum>P. americanum×P. purpureum>S. sudanense>P. hydridum. The three amendments all significantly improved the germination percentage, germination energy and germination index of P. hydridum, and for the other three grasses the germination energy and germination index in the mixed amendment treatment of diatomite and charcoal were also significantly higher than those of the control group (P<0.05). Compared with the control group, in the amendment treatments, the fresh weights of P. americanum×P. purpureum, P. purpureum, P. hydridum and S. sudanense were increased by 36.54%, 7.69%, 35.71% and 23.88%, respectively. Amendment application also enhanced chlorophyll content and the activities of antioxidant enzymes (superoxide dismutase, peroxidase, catalase), while the malondialdehyde content of leaves was decreased. Based on the germination, growth and physiological parameters, for the tested bioenergy grasses grown on the electrolytic manganese residue, P. purpureum with 2.5% charcoal and 2.5% diatomite amendment performed best, followed by P. americanum×P. purpureum with 5% diatomite amendment.