水稻灌浆期耐热性的品种间差异及其与剑叶光合特性和内源多胺的关系

 对65个不同来源的早籼稻品种进行了灌浆期耐热性的鉴定研究,并比较了耐热性相差很大的品种灌浆期高温胁迫前后的生理反应。结果表明：秕粒率、实粒重、整精米率、垩白度、蛋白质含量的胁迫指数可作为水稻品种灌浆期耐热性田间直接鉴定的 5个指标,可采用隶属函数值法对各品种的耐热性进行综合评价;不同品种的耐热性存在相当大的差异,筛选出了几个耐热性很强的品种;高温胁迫严重影响水稻的光合能力,但耐热性强的品种剑叶的光合速率高温胁迫后下降幅度明显较小,胁迫解除后恢复的程度也更高,叶绿素含量、RuBPc 活性及内源多胺含量的变化趋势与光合速率相一致,是水稻耐高温逼熟的重要生理特征。     

Antibacterial activity of turmeric oil: a byproduct from curcumin manufacture.

Curcumin, the yellow color pigment of turmeric, is produced industrially from turmeric oleoresin. The mother liquor after isolation of curcumin from oleoresin contains approximately 40% oil. The oil was extracted from the mother liquor using hexane at 60 degrees C, and the hexane extract was separated into three fractions using silica gel column chromatography. These fractions were tested for antibacterial activity by pour plate method against Bacillus cereus, Bacillus coagulans, Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Fraction II eluted with 5% ethyl acetate in hexane was found to be most active fraction. The turmeric oil, fraction I, and fraction II were analyzed by GC and GC-MS. ar-Turmerone, turmerone, and curlone were found to be the major compounds present in these fractions along with other oxygenated compounds.     

Effects of repeated manure and fertilizer phosphorus additions on soil phosphorus dynamics under a soybean-wheat rotation

 Soil P availability and efficiency of applied P may be improved through an understanding of soil P dynamics in relation to management practices in a cropping system. Our objectives in this study were to evaluate changes in plant-available (Olsen) P and in different inorganic P (P_i) and organic P (P₀) fractions in soil as related to repeated additions of manure and fertilizer P under a soybean-wheat rotation. A field experiment on a Typic Haplustert was conducted from 1992 to 1995 wherein the annual treatments included four rates of fertilizer P (0, 11, 22 and 44 kg ha^–1 applied to both soybean and wheat) in the absence and presence of 16 t ha^–1 of manure (applied to soybean only). With regular application of fertilizer P to each crop the level of Olsen P increased significantly and linearly through the years in both manured and unmanured plots. The mean P balance required to raise Olsen P by 1 mg kg^–1 was 17.9 kg ha^–1 of fertilizer P in unmanured plots and 5.6 kg ha^–1 of manure plus fertilizer P in manured plots. The relative sizes of labile [NaHCO₃-extractable P_i (NaHCO₃-P_i) and NaHCO₃-extractable P₀ (NaHCO₃-P₀)], moderately labile [NaOH-extractable P_i (NaOH-P_i) and NaOH-extractable P₀ (NaOH-P₀)] and stable [HCl-extractable P (HCl-P) and H₂SO₄/H₂O₂-extractable P (resisual-P)] P pools were in a 1 : 2.9 : 7.6 ratio. Application of fertilizer P and manure significantly increased NaHCO₃-P_i and -P₀ and NaOH-P_i, and -P₀ fractions and also total P. However, HCl-P and residual-P were not affected. The changes in NaHCO₃-P_i, NaOH-P_i and NaOH-P₀ fractions were significantly correlated with the apparent P balance and were thought to represent biologically dynamic soil P and act as major sources and sinks of plant-available P. Received: 23 October 1997     

Genetic basis of variation for salt tolerance in maize ( Zea mays L).

The genetic basis of salt tolerance was examined in selected salt tolerant and sensitive material from a sample of accessions previously assessed for variability in salinity tolerance. The North Carolina Model 2 Design and analysis was followed, tolerance being assessed in 10-day-old seedlings grown in salinized solution culture at control (0 mM), 60 mM and 80 mM NaCl concentrations). Salinity tolerance was shown to be under the control of genes with additive and non-additive effects, with broad and narrow sense heritability estimates being approximately 0.7 and 0.4 over all treatments. This revised version was published online in July 2006 with corrections to the Cover Date.     

Pesticides and heterotrophic nitrogen fixation in paddy soils

The effect of three pesticides, benomyl, carbofuran and gamm-BHC at 5 parts 10⁶, rates equivalent to recommended field levels, on the heterotrophic N₂ fixation in five air-dried, cellulose-amended, submerged tropical soils was invevstigated employing ¹⁵N tracer technique under laboratory conditions. Addition of benomyl, a carbamate fungicide, to alluvial, laterite and two acid sulphate soils resulted in significant increases in N₂ fixation, while carbofuran, a methylcarbamate insecticide, exerted a stimulatory effect on N₂ fixation in alluvial, alterite and acid saline soils. Gamma-BHC, a chlorinated hydrocarbon insecticide, stimulated N₂ fixation in alluvial and acid sulphate pokkali solis, while considerable inhibition of N₂ fixation was evident inother soils. Results showed differential responses of specific groups of N₂-fixing organisms to the pesticides depending ont he soil type.     

A new high in fish production in India with record yields by composite fish culture in freshwater ponds

Composite fish culture of the Indian major carp, Catla catla, Labeo rohita and Cirrhinus mrigala together with the Chinese silver carp Hypophthalmichthys molitrix and grass carp Ctenopharyngodon idella and the Indonesian strain of common carp (Cyprinus carpio communis) was carried out in experimental ponds in 1971–1972 and 1973–1974. The management techniques adopted aimed at high yields of marketable fish (around 1 kg) in 1 year.In the first year, production varied from 3 889 to 5 600 kg/ha/year and this rose to an average of 8 200 kg/ha/year with a maximum of 9 389 kg/ha/year in the second year. The important changes made to the management schedule in 1973 were increased stocking density, greater use of feed and fertilizers, and provision of more weeds for grass carp.The experimental studies demonstrate the practicability of raising large crops of healthy marketable fish in India.     

微生态制剂与土霉素对三元杂肉猪生产的比较实验

本试验选用三元杂肉猪作为试验动物,随机分成4组,分别在肉猪的基础饲粮中添加微生态制剂-宝肠安和抗生素-土霉素添加剂,并与空白对照组进行为期39天的比较研究试验。结果表明,饲粮中添加微生态制剂可提高肉猪饲料转化效率和饲养效益,猪的增重、采食量及抗病率等与使用土霉素的相当,并且消除猪粪异臭、改善环境等效果较土霉素理想。微生态制剂替代土霉素等抗生素具有明显的综合效益。     

Development of Temporal Model for Forecasting of Helicoverpa armigera (Noctuidae: Lepidopetra) Using Arima and Artificial Neural Networks

Helicoverpa armigera (Hübner) (Noctuidae: Lepidopetra) is a polyphagous pest of major crops grown in India. To prevent the damage caused by H. armigera farmers rely heavily on insecticides of diverse groups on a regular basis which is not a benign practice, environmentally and economically. To provide more efficient and accurate information on timely application of insecticides, this research was aimed to develop a forecast model to predict population dynamics of pod borer using Autoregressive Integrated Moving Average (ARIMA) and Artificial Neural Networks (ANN). The data used in this study were collected from the randomly installed sex pheromone traps at International Crops Research Institute for the Semi-arid Tropics (ICRISAT), Patancheru, Hyderabad. Several ARIMA (p, d, q) (P, D, Q) and ANN models were developed using the historical trap catch data. ARIMA model (1,0,1), (1,0,2) with minimal BIC, RMSE, MAPE, MAE, and MASE values and higher R² value (0.53) was selected as the best ARIMA fit model, and neural network (7-30-1) was found to be the best fit to predict the catches of male moths of pod borer from September 2021 to August 2023. A comparative analysis performed between the ARIMA and ANN, shows that the ANN based on feed forward neural networks is best suited for effective pest prediction. With the developed ARIMA model, it would be easier to predict H. armigera adult population dynamics round the year and timely intervention of control measures can be followed by appropriate decision-making schedule for insecticide application.     

一例引起史氏鲟鱼创口感染的病原菌分离与鉴定

分离和鉴定引起史氏鲟鱼创口感染的病原菌,为史氏鲟鱼疾病防治提供科学依据。本实验分析了一例刚捕获的患有经微创手术后创口感染疾病的史氏鲟腐败肉和肝脏的细菌菌相,分离获得优势菌株YSJ01,对优势菌进行了形态学、药物敏感性试验、动物感染试验和VITEK全自动微生物分析系统鉴定。结果显示：菌株YSJ01为革兰氏阳性菌;VITEK全自动微生物系统鉴定菌株YSJ01为致病性嗜水气单胞菌;动物感染试验证明：史氏鲟经创伤感染后表现为创口溃烂的典型症状;药敏试验结果表明：菌株YSJ01对氟苯尼考、复方新诺明、大观霉素、利福平、强力霉素、卡那霉素等9种药物敏感。对青霉素、氨苄西林、羧苄青霉素、万古霉素、新生霉素、土霉素、萘啶酸、阿莫西林、林可霉素等表现出耐药性。本研究为南方史氏鲟鱼经微创手术后创口感染疾病的防治提供了重要的实验依据。     

北京山区小流域综合治理智能决策信息管理系统的研制和开发

专家系统技术能够有效地解决小流域综合治理过程中非结构化和半结构化的问题 .该文在总结归纳北京山区小流域综合治理领域专家知识的基础上 ,采用产生式知识表达方法建立了小流域综合治理专家知识库 ,并集成地理信息系统技术、决策支持技术和数据库技术 ,研制开发了以专家系统为核心的小流域智能决策信息管理系统 .系统设计了信息管理、知识库管理、专家决策、可视化分析、可持续发展评价等功能模块 ,并以石匣小流域为例 ,介绍了系统在北京山区小流域综合治理和可持续发展评价中的应用 .