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51.
肖和良 《猪业科学》2020,37(2):76-79
桑叶养猪实用技术分为桑树种植技术和桑叶干粉发酵养猪技术两个部分。利用荒地种植桑树,降低生猪养殖饲养成本,桑叶养猪种养结合,成为生态农业典范。桑叶干粉发酵技术,提高了桑叶干粉的可消化率和饲料功能。桑叶干粉发酵料占配方6%~10%,做成桑叶猪饲料,替代3%~5%鱼粉、豆粕等蛋白质饲料,节约了饲料成本。桑叶喂养猪(简称桑叶猪,下同)的猪肉中含有肌苷酸等风味物质,显著提高猪肉胴体品质和猪肉风味。设计猪尿处理,采用红泥膜沼气池降解工程工艺应用后,降解水兑2倍清水对桑树喷灌工艺,减少人工处理劳力和成本费用。设计10%抗非洲猪瘟中药饲料添加剂+桑叶饲料,预期防治非洲猪瘟总效果85%以上。桑叶养猪实用技术可行,供同行参考。  相似文献   
52.
Brassica rapa L. is a genetically diverse parent species of the allotetraploid species, oilseed rape (B. napus) and a potential source of drought tolerance for B. napus. We examined the effect of a 13‐day drought stress period during the early reproductive phase, relative to a well‐watered (WW) control, on subsequent growth and development in nine accessions of B. rapa and one accession of Brassica juncea selected for their wide morphological and genetic diversity. We measured leaf water potential, stomatal conductance, water use, and leaf and bud temperatures during the stress period and aboveground dry weight of total biomass at maturity. Dry weight of seeds and reproductive tissue were not useful measures of drought tolerance due to self‐incompatibility in B. rapa. The relative total biomass (used as the measure of drought tolerance in this study) of the 10 accessions exposed to drought stress ranged from 47 % to 117 % of the WW treatment and was negatively correlated with leaf‐to‐air and bud‐to‐air temperature difference when averaged across the 13‐day stress period. Two wild‐type (B. rapa ssp. sylvestris) accessions had higher relative total and non‐reproductive biomass at maturity and cooler leaves and buds than other types. We conclude that considerable genotypic variation for drought tolerance exists in B. rapa and cooler leaves and buds during a transient drought stress in the early reproductive phase may be a useful screening tool for drought tolerance.  相似文献   
53.
以T5转hrpZPsta基因大豆JN29-705-15和JL30-187为材料,利用实时荧光定量PCR技术(Quantitative Real Time PCR,qRT-PCR)检测了目标基因在转基因大豆不同组织中的表达量,分别利用下胚轴侵染法和叶面喷施法鉴定疫霉根腐病抗性和灰斑病抗性,并分析目的基因表达量与疫霉根腐病和灰斑病抗性的相关性。结果表明:hrpZPsta基因在大豆的叶、茎、根、籽粒中均有表达,二个株系平均相对表达量分别为8.2/6.1、0.9/0.7、6.5/4.6和0.8/0.7;T5转hrpZPsta基因大豆抗疫霉根腐病和灰斑病能力与野生型相比均有所提高,JN29-705-15对疫霉根腐病抗性从感病提高到中抗,而JL30-187从中抗提高到抗病;hrpZPsta基因在叶中的表达量也与抗灰斑病能力呈正相关,与病情级别呈极显著负相关。试验结果初步证明了外源基因hrp ZPsta在大豆植株中的表达量与受体植株对疫霉根腐病和灰斑病抗性存在一定的相关性。  相似文献   
54.
This study was conducted to evaluate the influence of seed priming on drought tolerance of pigmented and non‐pigmented rice. Seeds of pigmented (cv. Heug Jinju Byeo) and non‐pigmented (cv. Anjoong) rice were soaked in water (hydropriming) or solution of CaCl2 (osmopriming). Seeds were sown in soil‐filled pots retained at 70 (well‐watered) and 35% (drought) water‐holding capacity. Drought stress caused erratic and poor stand establishment and decreased the growth of both rice types. More decrease in plant height and leaf area under drought stress was noted in pigmented rice, whereas decrease in root length and seedling dry weight, under drought, was more obvious in non‐pigmented rice. Pigmented rice maintained more tissue water and photosynthesis and had more polyphenols, flavonoids and antioxidant activity than non‐pigmented rice. Seed priming was effective in improving stand establishment, growth, polyphenols, flavonoids and antioxidant activity; however, extent of improvement was more in pigmented rice under drought. In conclusion, drought caused erratic germination and suppressed plant growth in both rice types. However, pigmented rice had better drought tolerance owing to uniform emergence, and better physiological and morphological plasticity. Seed priming was quite helpful in improving the performance of both rice types under drought and well‐watered conditions.  相似文献   
55.
根据铜仁烤烟单叶重的调查数据,认真梳理了铜仁烤烟单叶重的现状,分析了铜仁烤烟单叶重存在的问题,从烟叶收购政策和烟叶生产技术两个方面有针对性的提出提升铜仁烟叶质量的对策,为铜仁烤烟产业的持续健康发展提供理论指导。  相似文献   
56.
为了分析叶片营养元素对黔南州核桃优树坚果品质的影响,通过方差分析和相关分析研究了叶片营养元素与坚果品质之间的相关关系。结果表明:不同品种的核桃优树单株的坚果品质指标间存在显著差异;叶片钙、铜和锰显著影响核桃坚果品质。可以通过核桃叶片营养元素的诊断来提高坚果品质。  相似文献   
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59.
The effects of the severity and timing of leaf removal(LR) on the amino acids of Sauvignon Blanc grapes and wines were studied during the 2017 growing season. High-performance liquid chromatography(HPLC) was used to analyze the amino acids profiles of grape berries and wines. The basal leaves were removed at three time points(40, 56 and 72 days after flowering, named LR40, LR56 and LR72, respectively) at two severity levels(one at which the first, third, and fifth basal leaves of each shoot were removed(50% level); and another at which the first six basal leaves were removed(100% level)). The results showed that leaf removal had little impact on total soluble solids(°Brix), titratable acidity, pH or berry weight. The LR72-50% treated grapes had higher berry weight, titratable acidity and °Brix than those of the other treatments. The highest concentrations of total amino acids and of total amino acids except proline were detected in LR72-50% treated grapes(2 952.58 and 2 764.36 mg L~(-1), respectively); the lowest were detected in LR72-100% treated grapes(2 172.82 and 2 038.71 mg L~(-1), respectively). LR72-50% treatment significantly promoted the synthesis of aspartic acid, serine, arginine, alanine, aminobutyric acid and proline at both severity levels for grapes, the concentrations of all of these amino acids were increased relative to the control concentrations. The LR72-50%, LR40-100% and LR72-100% treated wines had higher total amino acids concentrations and higher concentrations of some individual amino acids, such as arginine, alanine and serine, than did the control wines. Of all the amino acids studied, glycine, tyrosine, cysteine, methionine and lysine were not significantly influenced by the timing or severity basal defoliation in grapes and wines. The present study reveals the effects of the timing and severity of leaf removal on the amino acids profiles of grapes and wines.  相似文献   
60.
[目的]探讨42.4%唑醚·氟酰胺悬浮剂对番茄叶霉病的田间防治效果。[方法]以10%苯醚甲环唑水分散粒剂和70%甲基硫菌灵可湿性粉剂为对照药剂,采用小区试验研究42.4%唑醚·氟酰胺悬浮剂对番茄叶霉病的防治效果。[结果]42.4%唑醚·氟酰胺悬浮剂在剂量为150.0~225.0 g a.i./hm2时,对番茄叶霉病的防治效果为83.37%~91.63%,与10%苯醚甲环唑水分散粒剂120.0g a.i./hm~2对番茄叶霉病的防治效果无显著差异,但显著高于70%甲基硫菌灵可湿性粉剂562.5 g a.i./hm~2的防治效果。[结论]42.4%唑醚·氟酰胺悬浮剂可广泛用于番茄叶霉病的防治。  相似文献   
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