不同类型向日葵籽粒的理化性质

为明确不同类型向日葵籽粒理化性质与利用价值,以3种不同类型向日葵籽仁为研究对象,检测其粗蛋白质、粗脂肪、氨基酸、微量元素、维生素E和植物甾醇含量,脂肪酸组成以及抗氧化活性.研究表明,观赏向日葵阿尔卑斯橙子红晕黑心和食用向日葵JZ055粗脂肪含量分别为44.55％和41.26％,低于油用向日葵陇葵杂6号(49.93％),...     

一种快速检测向日葵地块土壤中黄萎病菌微菌核的新方法

由大丽轮枝孢菌侵染引起的向日葵黄萎病是一种重要的土传病害,微菌核是该病害主要的初侵染来源。目前,土壤中大丽轮枝孢菌微菌核的定量检测方法多操作步骤复杂繁琐,如利用PCR方法进行检测,对仪器设备和操作人员的素质都有较高的要求,而常规的土壤梯度稀释湿筛法的实验周期长且检测效率低,因此,建立一种快速定量检测土壤中大丽轮枝孢菌微菌核的方法,对于向日葵黄萎病的预报预测和防控非常重要。为了能够快速的定量检测土壤中微菌核的数量,以期探明不同耕作方式地块中土壤微菌核数量的差异,本实验建立了一套操作相对简单,实验周期较短的微菌核快速分离和定量检测的方法,即采样器—干筛法。该方法将微生物采样器和选择性培养基相结合,基于微生物采样器的撞击法原理,使土壤微生物粒子加速撞击到选择性培养基的培养皿表面,经培养后可见单菌落形成。利用该方法对内蒙古巴彦淖尔市不同的向日葵黄萎病发病地块中采集到的土壤样本中微菌核进行了定量检测,结果表明：两年向日葵连作地（样地1）土壤中微菌核的数量最多,平均每克土样中含有微菌核32.80个;与非寄主作物玉米轮作地块（样地2）土样中微菌核的数量最少,平均每克土样中含有微菌核11.80个,与寄主作物打籽葫芦轮作地块（样地3）微菌核数量介于二者之间。利用该方法能够明显区分不同地块土壤中微菌核的数量。通过和荧光定量PCR检测的结果进行相关性分析发现,该方法能够准确检测土壤中大丽轮枝孢菌微菌核的数量。     

Growth and economic analysis of freshwater prawn,Macrobrachium rosenbergii (de Man), produced with feeds substituting sunflower cake for fish meal,soya bean meal and mustard oil cake

A feeding trial with Macrobrachium rosenbergii was carried out to test the effectiveness of sunflower cake (SFC) as a replacement for conventional protein sources. Four isonitrogenous (~30% crude protein) and isocaloric (388–402 kcal) diets were formulated. Diet‐1 was a control made with conventional ingredients including fish meal, soya bean meal and mustard oil cake. Diet‐2, Diet‐3 and Diet‐4 were made with 30%, 40% and 50% SFC, respectively, replacing the usual protein sources used in Diet‐1. After 100 days, diets with SFC inclusion showed favourable growth and economic performance trends compared to control diet‐1, but without significant differences (p > .05). Better production (572.89 ± 62.99 kg/ha) was observed with Diet‐4 followed by Diet‐2, Diet‐3 and Diet‐1. Diet‐4 revealed the best feed conversion ratio (2.56 ± 0.24), specific growth rate (1.18 ± 0.05) and protein efficiency ratio (1.14 ± 0.10) among these diets. Whole carcass composition analysis revealed highest crude protein (18.19%) and lipid (4.43%) content in prawns fed Diet‐3 followed by Diet‐4. Highest total income, gross margin and benefit cost ratio (BCR) per hectare from prawns were US$5,759, US$2,623 and 1.84, respectively, found in Diet‐4. This study demonstrates that 30%–50% inclusion of SFC has favourable impacts on productivity and profitability compared with controls, with 50% SFC inclusion as the most cost‐effective diet for prawns without apparent compromise in growth, flesh quality or economics. The performances of the diets suggest that SFC may be a suitable substitute for fishmeal, soya bean meal and mustard oil cake in prawn feed. The effectiveness of higher SFC concentrations should also be investigated.     

盐渍化土壤向日葵水-肥耦合试验研究

以内蒙古河套灌区主要作物油料向日葵为研究对象,进行了田间试验,采用312-D最优饱和试验设计方案,随机排列,2次重复,以产量为目标函数建立了不同盐分水平下的回归模型,并进行分析。研究结果表明,在盐渍化地区土壤中水肥因子的影响效应轻度盐渍化土壤依次为水分、磷、氮,中度盐渍化土壤依次为水分、氮、磷。最佳水肥配比范围轻度灌水量为1 581～2 116 m3/hm2,中度灌水量为1 088～1 549 m3/hm2,氮为225 kg/hm2,磷为150 kg/hm2。     

Exogenous xylanase improves growth,protein digestibility and digestive enzymes activities in Nile tilapia,Oreochromis niloticus,fed different ratios of fish meal to sunflower meal

A 3 × 2 factorial experiment was designed to evaluate the effect of different ratios of fish meal (FM): sunflower meal (SFM) with or without exogenous xylanase supplementation on growth, feed utilization, digestive enzymes activities, apparent digestibility, intestinal and liver morphology and chemical composition of Nile tilapia, Oreochromis niloticus. Three isonitrogenous (329.80 g/kg of crude protein) and isoenergetic (18.46 MJ/kg gross energy) experimental diets were formulated as SFM₁ (FM:SFM = 2:1), SFM₂ (FM:SFM = 1:1) and SFM₃ (FM:SFM = 1:2) based on protein content. Each diet was supplemented with 0 or 0.5 g/kg of exogenous xylanase and was fed to triplicate groups of twelve fish (with initial weight, 1.31 ± 0.02 g) for 84 days. After 84 days of feeding period, the highest weight gain, specific growth rate, protein efficiency, protein productive value and the best feed conversion ratio were recorded in fish fed either SFM₁ or SFM₂ supplemented with exogenous xylanase. Whereas lowest growth performance was recorded in fish fed SFM₂ and SFM₃ un‐supplemented with xylanase. The highest activities of chymotrypsin, trypsin, lipase, amylase, alkaline phosphatase and cholecystokinin were observed in fish fed SFM₁ and SFM₂ diets supplemented with xylanase. The highest ADCs of dry matter, protein, lipid and digestible energy were recorded in fish fed SFM₁ and SFM₂ diets supplemented with exogenous xylanase. Supplementation of exogenous xylanase improved muscularis mucosa thickness, height of mucosal folds and enterocytes of intestinal fish. Addition of exogenous xylanase increased the calcium and phosphorus retention. Results of this study indicated that the addition of exogenous xylanase to diet containing high inclusion level of sunflower meal improved growth, digestive enzymes, nutrient digestibility, histological morphometric of liver and intestine and nutrient retention.     

Effect of non‐starch polysaccharide composition and enzyme supplementation on growth performance and nutrient digestibility in Nile tilapia (Oreochromis niloticus)

The experiment investigated whether the effect of enzyme supplementation on performance and nutrient digestibility is dependent on type of the ingredient(s) used, by incorporating wheat bran (WB), sunflower meal (SFM) and citrus pulp (CP) to a reference diet (REF). Those ingredients are known to be rich in different types of non‐starch polysaccharides (NSP). Diets were supplemented with and without (control) an enzyme mix (phytase 1,000 FTU/kg and xylanase U/kg) according to a 2 × 4 factorial arrangement. In total, 24 tanks (3 replicates/treatment) were used with 30 fish each (Nile tilapia, Oreochromis niloticus; mean initial body weight 41 g). Fish were restrictively fed the experimental diets for 43 days (80% of expected satiation). Enzyme supplementation affected the absolute growth (g/day) and FCR (p < 0.05), improving the growth of fish fed the WB and SFM diets, while fish fed the REF and CP diets did not benefit. NSP, energy, ash, phosphorous and calcium digestibility improved with enzyme supplementation (p < 0.05). There was an interaction effect on all growth parameters, as well as the digestibility of energy and phosphorus (p < 0.05). This indicates that the effectiveness of the enzymes was dependent on the NSP‐rich ingredient used and thus the composition of the NSP fraction.     

Nutrient responses and glutamate and proline metabolism in sunflower plants and calli under Na2SO4 stress

The growth of Helianthus annuus L. calli and plants was reduced in the presence of Na₂SO₄ (10, 25, 50, and 100 mM). SO₄^2— and Na concentrations increased in stressed calli and plants while NO₃^—, Cl^—, P, K, and Mg decreased in stressed plants and Ca in shoots. Stressed calli showed decreases of NO₃^—, Ca, K, and Mg concentrations. Calli adapted to 50 mM Na₂SO₄ accumulated more K and Ca and less ammonium than stressed non‐adapted calli. Proline exhibited increases in stressed calli and plants that were accompanied by decreases of proline oxidase activities while pyrroline‐5‐carboxylate reductase (P5CR) and ornithine aminotransferase (OAT) activities increased. Adapted calli accumulated more proline and had higher P5CR and OAT activities than stressed non‐adapted calli. Glutamate concentration decreased with stress, together with a stimulation of cytosolic glutamine synthetase (GS1) and a decrease of plastidal GS (GS2) activity. These data strongly suggest that the increase of P5CR and GS1 activities are responsible for the decrease of glutamate concentration leading, together with the stimulation of OAT and the inhibition of the proline oxidation metabolism, to an increase of proline levels in Na₂SO₄‐stressed sunflower cells. These data also show that salt stress increases the release of endogenous ammonium and suggests that the increase of GS1 activity plays an important role in its elimination.     

冀北油葵主要栽培因素对产量的影响

为了研究主要栽培因素对油葵产量的影响,确定冀北地区油葵最优栽培方案.本研究采用5因子二次回归正交旋转组合设计,建立播期、密度、氮肥、磷肥和钾肥与油葵产量的效应函数.结果 表明,播期、密度、氮肥、磷肥和钾肥随着投入量的增加油葵产量呈先升高后下降趋势,其中播期、播期氮肥互作起着重要的作用.目标产量大于2916.67 kg/...     

弓形钳叶甲为害棉花和向日葵调查初报

2018年5月在新疆阜康发现弓形钳叶甲 Labidostomis arcuata Pic成虫高密度发生, 严重为害棉花、向日葵幼苗。本文介绍了此次弓形钳叶甲的发生为害情况, 并分析了其可能成因。这是该虫在我国为害农作物的首次报道。