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91.
92.
以‘808’香菇为试材,研究了1-MCP处理、肉桂精油结合1-MCP处理对香菇采后褐变和感官品质的影响。结果表明:随着贮藏时间的延长,对照组(未处理)香菇感官品质下降,表面L*值降低、褐变严重,开伞度增加;从不同浓度1-MCP处理的保鲜效果来看,与对照(未处理)、0.5 mg·L-1和10.0 mg·L-1 1-MCP相比,2.0 mg·L-1 1-MCP处理保鲜效果最好,菇体开伞少,质地硬度大、色泽好;从肉桂精油结合1-MCP处理来看,以5μL·L-1肉桂精油结合2.0 mg·L-1的1-MCP处理效果最好,延迟了香菇褐变和开伞的发生,维持了香菇表面较高的L*值高,感官得分最高。  相似文献   
93.
A field study conducted for three crop years (June?–?July) from 1995?–?96 to 1997?–?98 at the Indian Agricultural Research Institute, New Delhi involving five rice-based cropping systems and six nutrient combinations indicated that rice?–?wheat?–?mungbean (RWM), rice?–?potato?–?mungbean (RPM), rice?–?rapeseed?–?mungbean (RRsM) and rice?–?clover (RC) cropping systems gave 0.7?–?1.0, 3.2?–?5.9, 0.2?–?2.2 and 1.5?–?3.6 t ha?1 yr?1, respectively, higher productivity and removed 7.9?–?22.6, 38.0?–?64.5, 53.0?–?61.8 and 51.4?–?66.1?kg ha?1 yr?1, respectively, more nitrogen, 2.3?–?7.1, 14.5?–?22.8, 3.8?–?7.2 and 17.3?–?21.7?kg ha?1 yr?1, respectively, more phosphorus and 1.6?–?11.4, 15.3?–?42.3, 8.2?–?22.7 and 40.8?–?57.8?kg ha?1 yr?1, respectively, more potassium than the rice?–?wheat (RW) cropping system which led to a net balance of +?151, +?58, ??153 and ??167?kg ha?1 of nitrogen, +?13, ??27, ??8 and ??59?kg ha?1 of phosphorus and ??549, ??551, ??558 and ??691?kg ha?1 of potassium after three cycles of RWM, RPM, RRsM and RC cropping systems, respectively against a net balance of +?201, +?26 and ??533?kg ha?1 of N, P and K, respectively in the RW cropping system. Application of FYM along with NPK in these cropping systems changed the negative balance of nitrogen and phosphorus into positive balance and reduced the negative balance of potassium by 151?–?378?kg ha?1. Application of P and K fertilizers along with nitrogen also helped in arresting the negative balance of P and K under different rice based cropping systems. These results thus indicate that balanced use of NPK and FYM plays a major role for sustaining the productivity of a cropping system.  相似文献   
94.
95.
试验比较了来自东北、华北等地小麦根腐病菌共30个菌株,从中已筛选出毒力强而稳定的菌株(002号)。初步明确采用改良Fries加小麦健叶汁的液体培养基培养根腐茵,每天振荡4次,每次20min,培养15d后的培养物滤液,在5℃下可保存2个月,用15磅高压灭菌30min及煮沸浓缩均不影响毒素的作用。在几种Hs—毒素制剂中,以粗提物制剂的毒素作用最强,病叶提取液和培养滤液次之。应用根冠细胞测定法评价Hs—毒素的作用比用抑制种子根伸长的种苗“萌发包”法更为灵敏,精确,快速。测定小麦离体:浪冠细胞的最佳条件是:黑暗25℃下处理6h;根冠细胞浓度为500—1000个/ml;粗提毒素稀释液pH6—7。  相似文献   
96.
Twenty-one microbial preparations recommended for controlling pathogenic fungal strains causing root rot and wilt diseases of faba bean were investigated for antibiosis against several symbiotic and associative diazotrophs adopting a modified agar-plate-inhibition-zone assay. Rhizobium and Bradyrhizobium exhibited a somewhat similar susceptibility to biocontrol agents while associative diazotrophs showed variable responses. Azotobacter, compared to others, was severely inhibited by such bio-candidates. The members of the biofertilizer formulation ‘Biofertan’ did bear mixed cultivation with the majority of biocontrol agents. Among those, Bacillus subtilis was deemed the pioneer. In pot experiments, almost all the antagonists significantly restricted the severity of root rot and wilt diseases besides modifying faba bean seedling stand and improving plant development. This was very obvious with shoot biomass increases of >?50%. Moreover, the bioagents successfully recovered the legume establishment, seriously injured due to pathogenic fungal infection. Simultaneous inoculation with Rhizobium and biocontrol agents provided more growth stimulation compared to either when introduced individually. Field-grown faba beans were inoculated with the diazotroph and representatives of biocontrol strains by two different methods, seed coating and over-head soil. Growth parameters determined were the highest when the legume plant was seed-coated by Rhizobium simultaneously over-head soil inoculated with the bacterial bioagents; this was reported with Bacillus subtilis and Pseudomonas aerugenosa. The significance of combined application of biofertilizer and bioagent to ensure cheap, clean and safe farm products is discussed.  相似文献   
97.
采用石蜡切片技术对粗毛淫羊藿的大孢子形成及雌配子体发育过程进行观察。结果表明:粗毛淫羊藿子房单心皮1室,每室胚珠多数,双珠被,厚珠心,倒生胚珠。大孢子母细胞经减数分裂形成直线形排列的4个大孢子,合点端大孢子发育成功能大孢子,其余3个退化。胚囊发育类型为蓼型。  相似文献   
98.
Although preventive epidural morphine administration with bupivacaine is effective in producing long‐lasting analgesia, neuraxial anaesthesia can cause cardiovascular depression and pruritus. This report presents the development and treatment of hypotension and pruritus after intrathecal morphine and bupivacaine administration in a 3‐year‐old female spayed Domestic Short‐hair cat presented for surgical repair of a torn right cranial cruciate ligament. Opioid‐induced pruritus is not usually considered a frequently occurring complication, but may be easily misinterpreted as being dysphoria in recovery. It can be treated by administration of ondansetron, with human patients usually responding within 30 min after treatment.  相似文献   
99.
One thousand condemned pigs' kidneys were collected in February 2002 from two pig abattoirs in England to assess the lesions due to postweaning multisystemic wasting syndrome (pmws) and porcine dermatitis and nephropathy syndrome (pdns) and the possible contribution of ochratoxicosis; 174 of the kidneys were pale, 295 were swollen and 81 were abnormally firm with the gross appearance of fibrosis. The main macroscopic finding was the presence of multifocal pale cortical lesions, observed in 446 of the kidneys, and there were large cysts in 266 of them. Histopathological lesions of non-suppurative tubulointerstitial nephritis, with degeneration and fibrosis of renal tubules, were identified in 213 of 250 (85.2 per cent) of the kidneys examined. These lesions were consistent with those reported in cases of pmws and pdns. The tubular degeneration and fibrosis were also consistent with ochratoxicosis. A higher mean concentration of ochratoxin A was significantly (P=0.020) associated with the presence of multifocal pale cortical lesions consistent with ochratoxicosis, but a causal relationship was not confirmed because histochemistry was not used to detect ochratoxin in the lesions directly. There was no significant correlation between the microscopic lesions and the concentration of ochratoxin. The degenerative lesions may have been caused by previous exposure to ochratoxin that had subsequently been excreted, but the microscopic lesions also included non-suppurative interstitial nephritis, which was unlikely to have been caused by ochratoxicosis.  相似文献   
100.
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