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101.
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   
102.
以7种常见景天科多肉叶片为材料进行温度梯度处理,用电导率法测定细胞伤害率,观察供试材料对高温胁迫的耐受性。结果表明,55℃是姬秋丽、薄雪万年草、黄丽、胧月、八宝景天的细胞伤害率跃升临界温度,60℃是佛甲草和垂盆草的跃升临界温度。供试景天种类的叶型大小和取样方式不影响试验结果。  相似文献   
103.
本文利用NCEP/NCAR逐月可降水量的再分析资料,选取1983年1月-2012年12月共360个时次的数据,分析可降水量的变化趋势。得出结论:近30年内华南中部的可降水量总体上呈下降趋势;季节性变化明显,可降水量值呈夏高冬低趋势。  相似文献   
104.
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   
105.
以栽植于日光温室中适宜延迟栽培的‘贝达’砧‘意大利’葡萄为试材,自2013年8月1日始至落叶(2014年1月31日)止每天分别进行红光和蓝光不同光质延长光照至24:00补光处理,以不补光作为对照,研究不同光质补光处理对葡萄叶片衰老过程中叶片的外观形态特征、叶绿素含量、净光合速率、F_v/F_m、可溶性蛋白质含量和叶绿体超微结构的影响,为叶片抗衰老技术的研发提供理论依据。研究结果表明:补充红光显著提高了叶片的叶绿素含量、净光合速率、F_v/F_m值和可溶性蛋白质含量,叶绿体基粒片层排列整齐有序,明显减缓了叶绿体超微结构的解体,显著延缓叶片衰老;补充蓝光处理前期显著降低了叶片的叶绿素含量、净光合速率、F_v/F_m值和可溶性蛋白质含量,破坏了叶绿体的超微结构,加速了植株的衰老进程;但在叶片衰老后期,叶绿素含量、净光合速率、F_v/F_m值和可溶性蛋白质含量逐渐高于对照,并且叶绿体的基粒片层比对照排列整齐有序,在一定程度上延缓了叶片衰老。补充蓝光处理的叶片可溶性蛋白质含量一直显著高于补充红光和对照。综上,补充红光处理有效延缓了叶片衰老进程,延长了叶片的生理功能期。  相似文献   
106.
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   
107.
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   
108.
109.
The purpose of this study was to identify the dominant pathogens of Curvularia leaf spot and their pathogenicity variation in Huanghuaihai Region of China in recent years. In 2013 and 2016–2017, the occurrences of Curvularia leaf spots on maize were investigated in fields located in Henan, Hebei, Shandong, and Anhui provinces, and 292 fungi were isolated from diseased leaves. These fungal isolates were subjected to morphological identification, and 232 isolates were found to have about 70% uncurved conidia and were identified as Curvularia lunata var. Most of the conidia of 2 representative isolates, namely, HNWB-131 and HNWB-185, were oblong with parallel septations and were distinctly different from a reference isolate CX-3. For further determination, the internal transcribed spacer(ITS), glyceraldehyde 3-phosphate dehydrogenase(GPDH), the large subunit(LSU), and translation elongation factor 1-alpha(EF1-α) sequences of HNWB-131, HNWB-185, and CX-3 were amplified and sequenced. The results of sequence analysis showed that the 4 gene sequences from the 3 isolates had a similarity of more than 99% to C. lunata. Based on the sequences of ITS and the combined data of the 4 genes, neighbor-joining trees were constructed for phylogenetic analysis. The results indicated that these 3 isolates were clustered together with C. lunata. The expression of Clg2 p and ClUrase genes in mycelia and conidia was significantly(P0.05) higher in CX-3 than in HNWB-131 and HNWB-185. This study found that the dominant pathogen of Curvularia leaf spot was a new variety of C. lunata with morphological variations in Huanghuaihai Region from 2013 to 2017. The pathogenicity of the C. lunata var. was not significantly enhanced, and the expression of Clg2 p and ClUrase genes of C. lunata var. was decreased.  相似文献   
110.
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