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101.
近几年来兴宁市积极推广优质稻的生产,种植面积逐年增加。结合兴宁市优质稻栽培实践,总结了目前的示范推广情况,最后提出了配套的技术要点。  相似文献   
102.
Bull’s eye rot is a typical quiescent postharvest apple disease in major fruit-growing areas. The susceptibility of different apple cultivars to Neofabraea spp. (N. vagabunda and N. malicorticis) was assessed, with Granny Smith showing the most resistance and Cripps Pink the most susceptibility. To assess the factors involved in conidial germination, Neofabraea spp. were grown on crude protein extracts (CPEs) collected from apple fruits at different storage periods. Fungal germ tube growth rate and pathogenic enzyme (cellulase and xylanase) activity were assessed. Results showed that CPEs collected after 2 and 4 months of storage progressively stimulated conidial germination and germ tube elongation, while a lesser effect was observed from CPEs after 1 month of storage. Xylanase proved to be the main degrading enzyme secreted by all the isolates, while cellulase was produced only by N. vagabunda isolates. Overall, the isolate ID02 was the most virulent, based on more rapid germ tube elongation and greater activity of the lytic enzymes.  相似文献   
103.
连狮1 号是以连云港地区菜农提供的中狮头自留种为原始种,经4 代自交提纯选育成的大白菜新品种。株型紧凑, 整齐度较好,叶球为长筒翻心形,叶片呈长倒卵形,叶表面具有较深核桃纹并带稀疏茸毛。株高35 cm,外叶数约10 片, 叶球高28~32 cm、横径22~27 cm,单个叶球质量3.5~4.0 kg,每667 m2 叶球产量4 700 kg 左右,净菜率达83%。生育期 为90~95 d(天),田间抗病毒病、霜霉病、根肿病能力优于对照中狮头,适合在江苏、安徽、山东等地及其相近气候条件 地区秋季种植。  相似文献   
104.
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   
105.
以陕西榆林山地矮化密植梨枣树为研究对象,分析了不同水肥浓度对涌泉根灌枣树生育期内叶面积指数、果实发育和产量的影响。结果表明,不同水肥处理叶面积指数在枣树果实膨大期达到高峰,且稳定持续至果实成熟期末期,随后叶面积指数开始下降。叶面积指数随着萌芽展叶期灌水量的增加而增加,所有水肥处理下,枣数叶面积指数最大的是高水中肥处理(W1N2);所有处理中,高水、低水处理与低肥相组合,果实体积最大,中灌水处理为不施肥时果实的体积最大。单位枝长的果实数目最高的是中水中肥处理(W2N2),最低的是低水处理(W3),在一定范围内,适当施肥能促进枣果单位枝长的果实数目的增加,但肥液浓度过大,反而会抑制其增加。在一定条件下,所有处理中产量最高的是中水中肥处理(W2N2),产量超过2000kg/亩,最低的是低水高肥处理(W3N1),产量不到1000kg/亩。因此可以选择中水中肥处理(W2N2),能获得最高的产量。  相似文献   
106.
AIM:To investigate the inhibitory effect of thioredoxin 1 (Trx-1) over-expression on oxidative stress injury in 1-methyl-4-phenylpyridinium (MPP+)-induced rat pheochromocytoma PC12 cells by regulating NF-κB signaling pathway.METHODS:The PC12 cells were damaged by treatment with MPP+ at 1, 3 and 5 mmol/L, and the optimal concentration of 3 mmol/L was selected. The cell viability was measured by MTT assay. The oxidative stress indexes lactate dehydrogenase (LDH) activity, superoxide dismutase (SOD) activity and malondialdehyde (MDA) content in the cell culture supernatant were detected, and the protein expression of Trx-1 was determined by Western blot. Lentiviral infection with Ad-Trx-1-GFP sequence was used to establish a model of MPP+-treated PC12 cells with Trx-1 over-expression. The effects of Trx-1 over-expression on the cell viability, oxidative stress responses and NF-κB signaling pathway were determined by MTT assay, commercial kits and Western blot. The effects of phorbol 12-myristate 13-acetate (PMA), an activator of NF-κB signaling pathway, on the viability and oxidative stress of PC12 cells were observed. The NF-κB signaling pathway inhibitor pyrrolidine dithiocarbamate (PDTC) was used in MPP+-treated PC12 cells with Trx-1 over-expression, and the cell viability and oxidative stress responses were measured. RESULTS:The viability of PC12 cells, SOD activity in the supernatant and protein expression of Trx-1 were decreased, while LDH activity and MDA content in the supernatant were increased significantly by treatment with MPP+ at 1, 3 and 5 mmol/L. The effect of MPP+ at 3 mmol/L and 5 mmol/L was significantly greater than that at 1 mmol/L (P<0.05), and no significant difference between 3 mmol/L and 5 mmol/L was observed (P>0.05). The inhibitory effect of MPP+ on the viability of PC12 cells, and the oxidative stress injury and activation of NF-κB signaling pathway induced by MPP+ were significantly attenuated by over-expression of Trx-1. The inhibitory effect of MPP+ on the viability of PC12 cells and the oxidative stress injury induced by MPP+ were promoted by the activation of NF-κB signaling pathway, while the protective effects of Trx-1 over-expression on the MPP+-treated PC12 cells were enhanced by the inhibition of NF-κB signaling pathway. CONCLUSION:Over-expression of Trx-1 protects MPP+-treated PC12 cells from oxidative stress injury by regulating NF-κB signaling pathway.  相似文献   
107.
Sucrose synthases (SUS) are a family of enzymes that play pivotal roles in carbon partitioning, sink strength and plant development. A total of 11 SUS genes have been identified in the genome of Malus domestica (MdSUSs), and phylogenetic analysis revealed that the MdSUS genes were divided into three groups, named as SUS I, SUS II and SUS III, respectively. The SUS I and SUS III groups included four homologs each, whereas the SUS II group contained three homologs. SUS genes in the same group showed similar structural characteristics, such as exon number, size and length distribution. After assessing four different tissues, MdSUS1s and MdSUS2.1 showed the highest expression in fruit, whereas MdSUS2.2/2.3 and MdSUS3s exhibit the highest expression in shoot tips. Most MdSUSs showed decreased expression during fruit development, similar to SUS enzyme activity, but both MdSUS2.1 and MdSUS1.4 displayed opposite expression profiles. These results suggest that different MdSUS genes might play distinct roles in the sink-source sugar cycle and sugar utilization in apple sink tissues.  相似文献   
108.
109.
为明确两种有机硅助剂Silwet 408和Greenwet 7618对四氯虫酰胺防治菜青虫的增效作用,本文采用喷雾法测定四氯虫酰胺以推荐剂量、50%推荐用量分别与Silwet 408和Greenwet 7618的3 000倍稀释液混用对菜青虫的田间防效。结果表明,四氯虫酰胺以50%推荐用量分别与Silwet 408和Greenwet 7618混用,药后3 d对菜青虫的防效均与单独使用推荐剂量的防效无显著差异;药后7 d,50%推荐用量与Greenwet 7618混用对菜青虫的防效与推荐剂量的四氯虫酰胺仍无显著差异,而50%推荐用量与Silwet 408混用的防效显著降低;在药后14 d,所有处理对菜青虫无防治效果。因此,建议在生产上推广50%推荐用量的四氯虫酰胺与Greenwet 7618的3 000倍液混用防治菜青虫。  相似文献   
110.
湘紫薯174 是以浙紫薯1 号为母本、浙紫薯3 号为父本杂交选育而成的食用型紫心甘薯新品种,薯块纺锤形,薯皮 紫红色,薯肉紫色,结薯较集中整齐,单株结薯4~5 个,大中薯率82.7% 以上,熟食味好,抗黑斑病,中抗根腐病、茎线 虫病和薯瘟病;每667 m2 鲜薯产量1 913~2 359 kg,薯干产量549~736 kg;花青素含量为714.5 mg · kg-1(FW)。适宜在湖 南、湖北、江西、江苏、浙江等地春夏薯区种植。  相似文献   
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