利用国际水稻品种资源改良粳稻恢复系研究初探

以优良粳稻恢复系K1863为主体亲本，以国际水稻分子育种品种资源为供体亲本通过杂交并回交，获得了100多个K1863回交改造后代群体。对其中部分K1863回交改造后代进行了表型性状鉴定，初步表明被鉴定的多数K1863回交后代获得了主体亲本K1863对粳稻不育系的恢复能力，在回交后代中产生了稻瘟病抗性、耐盐性优于主体亲本K1863的材料，而且部分K1863回交改造后代的综合经济性状也优于主体亲本K1863。从而说明，利用国际水稻分子育种品种资源，通过大量回交，不仅可以在保留主体亲本的重要性状、保持与主体亲本性状相似性的同时，获得一些主体亲本本身不具有的有利性状，并选育出综合经济性状优于主体亲本的回交后代，因此通过本方法获得的回交后代材料具有重要的育种利用价值。本文还探讨了对这些K1863回交改造后代进行进一步利用改造的途径。     

分子标记在甘蓝遗传育种中的应用

本文综述了分子标记在甘蓝遗传育种中应用的几个方面：1、分子标记遗传图谱的建立；2、亲缘关系和遗传多样性的研究；3、基因定位；4、品种纯度鉴定；5、分子标记辅助选择。     

Agronomic Evaluation of Legume Cover Crops for Sustainable Agriculture

The agronomic characteristics of different legume cover crops and their effects on soil chemical properties were investigated in a short-term field study. We compared weed biomass, nitrogen equivalence, growth rate, leaf chlorophyll content, cover crop biomass, soil total organic carbon, and soil total nitrogen under eight different legume cover crops in a short-term field experiment. We found the highest growth rate, cover crop dry biomass, N plant content, and N contribution with C. ochroleuca plants, whereas for leaf chlorophyll content, soil organic carbon, and total nitrogen the highest values were found with M. pruriens. We did not find any significant difference among C. ochroleuca and M. pruriens for cover crop dry biomass. Our findings suggest that the incorporation of cover crops into the soil can change positively the soil chemical properties, such as soil organic carbon and total nitrogen. Our results also highlight the importance of considering the short-term effect of cover crops on the tropical soil fertility maintenance, in this case, Regosol.     

Effects of Salinity on Growth Physiology,Accumulation of Osmo-Protectant and Autophagy-Dependent Cell Death of Two Maize Variety

Maize is moderately sensitive to salt stress; therefore, soil salinity is a serious threat to its production worldwide. Here, two maize variety Kharif Shaktiman-1 and Pioneer 30 v92 were screened to understand the maize response to salt stress and its tolerance mechanisms. Difference in relative water content, membrane stability index, stomatal conductance, shoot and root fresh/dry weight has been analyzed under salinity. The effect of osmotic stress was also analyzed on the basis of accumulation of osmoprotentant like proline, glycine betaine and soluble sugar content. The gas exchange characteristics and autophagy-dependent cell death were used to analyses the physiological effects of osmotic stress at about 15 days after salt stress in maize. The results of relative water content, membrane stability index, stomatal conductance, accumulation of osomoprotectant was higher in Kharif Shaktiman-1, the autophagy-dependent cell death was less in Pioneer 30 v92, indicate that Kharif Shaktiman-1 has more salt tolerant ability than the Pioneer 30 v92. But the result of autophagy-dependent cell death showed an opposite trend, as it was higher in Kharif Shaktiman-1, indicate more cell damage in it under salinity. So molecular technique or marker based on autophagy-dependent cell death for the screening of stress tolerant trait in desired crop may act as method of choice.     

Vesicular Arbuscular Mycorrhizal (VAM) fungi- as a major biocontrol agent in modern sustainable agriculture system

In the present agricultural system, the discriminate use of synthetic chemical fertilizers has predominantly increased throughout the world. Moreover, using excessive use of fertilizers to increase production deteriorates the various soil qualities and pollute water body environment. So using VAM fungi as a biocontrol agent in modern sustainable agriculture, in terms of various parameters like reduction of damage caused by various pathogens, cost effectiveness, energy saving and also as an environment friendly, is a promising perspective in modern agriculture. Also control of plant pathogens in modern agriculture is presently accepted as a key practice in sustainable agriculture because it is based on the management of certain rhizosphere organisms, common components of ecosystems, known to develop antagonistic activities against harmful organisms. Vesicular Arbuscular Mycorrhizal Fungi interact with other microorganisms in the rhizosphere and various other soil constituents. Upon root colonization by VAMF, there occurs profound physiological changes in the host plant. Present agriculture system increasing demand for low-input agriculture and creates greater interest in soil microorganisms which are able to accelerate plant nutrition, health and improve soil quality. The importance of VAM in incresaing food production is far and wide; therefore these can be used in modern sustainable agriculture particulary as biocontrol agent. This review highlights the different interactions of Vesicular Arbuscular Mycorrhizal Fungi (VAMF) and the rule of these interactions in the biological control of plant pathogens. But the commercial use of Vesicular Arbuscular Mycorrhizal Fungi (VAMF) as biocontrol agents is still in its infancy. The main reason is the poor understanding of the mechanisms of the modes of action of VAM fungi in association with the host plants.     

Synthesis and characterization of sodium acrylate and 2-acrylamido-2-methylpropane sulphonate (AMPS) copolymer gels

A series of superabsorbents based on acrylic acid (AA), sodium acrylate, 2-acrylamido-2-methylpropane sulphonic acid, N,N′-methylene bis-acrylamide (MBA) were prepared by inverse suspension polymerization. These hydrogels were further crosslinked on the surface with polyethylene glycol-600 (PEG-600). The water absorbency or swelling behaviors for these xerogels in water and 0.9% saline solutions, both under free condition and under load were investigated. Absorption characteristics of these hydrogels were found to depend on nature and concentration of crosslinker in the system. It was also found that the saline absorption was significantly improved as the incorporation of AMPS in the polymer was increased. The surface crosslinking introduced in the polymers was found to improve the absorption under load characteristics without lowering the free water absorption capacities of the polymer to a considerable extent.     

Increasing water productivity for paddy irrigation in China

This paper introduces the research on practices to increase water productivity for paddy irrigation in China and summarizes the experience on implementation of the alternate wetting and drying (AWD) irrigation technique. The widespread adoption of the AWD practice on 40% of the rice growing area provides an opportunity for China to produce more food in the water-surplus south where it is wet and the traditional based paddy field agriculture is dominant. Physical and institutional measures leading to increasing water and land productivity in rice-based systems are discussed. Research studies show that AWD practice does not reduce rice yield, but does increase the productivity of water. Water use and thus water charges can be reduced. However, experience shows that demonstrations and training are needed to encourage farmer adoption. Furthermore, there are a range of complementary policies and practices, such as volumetric pricing or farm pond development, which provide incentives for adoption of AWD. Finally, there remain many scientific issues to be addressed. Application of the AWD technique in some regions is still very difficult because of both bio-physical and socio-economic problems. In conclusion, the widespread adoption of AWD is only a first step in the continuing effort to find practices that will increase water productivity for paddy irrigation in China.Dr. Yuanhua Li was a Professor and Dean in Wuhan University of Hydraulic and Electric Engineering from 1996 to 2000. After that, he has been a Professor and Deputy Director General of the National Centre for Irrigation and Drainage Development, Ministry of Water Resources, China. He has been doing research on irrigation principally for paddy since 1982.Dr. Randolph Barker is an agricultural economist and Professor Emeritus Cornell University. From 1966 to 1978 he served as head of the Economics Department, International Rice Research Institute, Los Banos, Philippines and from 1995 to 2004 was principal researcher, International Water Management Institute, Colombo, Sri Lanka.     

Vitamin C Enrichment of Fruit Juice Based Ready-to-Serve Beverages Through Blending of Indian Gooseberry (<Emphasis Type="Italic">Emblica officinalis</Emphasis> Gaertn.) Juice

Physiconutritional qualities of fruits viz. apple, lime, pome- granate, Perlette grape, and Pusa Navrang grape were analyzed and compared with those of Indian gooseberry (Emblica officinalis Gaertn.). Indian gooseberry juice contained the highest vitamin C (478.56 mg/100 ml). Hence, when gooseberry juice was blended with other fruits juice for the preparation of ready-to-serve (RTS) beverages, it boosted their nutritional quality in terms of vitamin C content. On the basis of overall sensory quality and vitamin C content, RTS beverage prepared by blending gooseberry and Pusa Navrang grape juice in 20:80 ratio was found to be the best.     

Immunotoxic responses of chronic exposure to cypermethrin in common carp

In the current study, laboratory evaluations were made to assess the immunomodulatory effect of cypermethrin on fingerlings of common carp (Cyprinus carpio L.). Results showed that 96-h LC50 of cypermethrin in common carp was estimated at 0.85 μg/L. Fish were exposed for 21 days to cypermethrin at three sub-lethal concentrations of 0.042, 0.085, and 0.17 μg/L that represented 5, 10, and 20%, respectively, of the 96-h LC50 of the pesticide for this fish species. Blood samples were taken after 7, 14, and 21 days of exposure. Immunological indices and resistance against bacterial infection were determined. Compared to the control group, the fish exposed to cypermethrin showed a significant increase in neutrophil ratio but exhibited a significant decrease in leukocyte number and lymphocyte ratio in treatments exposed to 0.17 and/or 0.085 μg/L after 21 days of exposure (p < 0.05). Serum protein level was significantly decreased in group exposed to 0.17 μg/L on day 14 and also in groups exposed to 0.085 and 0.17 μg/L on day 21 (p < 0.05). Immunoglobulin value was significantly reduced in groups exposed to 0.085 and 0.17 μg/L after 21 days of exposure (p < 0.05). Serum lysozyme activity and phagocytic activity were significantly decreased following exposure to 0.17 μg/L determined on days 14 and 21, post-exposure (p < 0.05). Mortality rate following the challenge with Aeromonas hydrophila significantly increased in fish exposed to 0.17 μg/L of cypermethrin. Overall, the present results indicate severe immunotoxicological effects of cypermethrin in common carp. Therefore, the use of cypermethrin in the proximities of common carp farms should be carefully considered.     

An overview of the ongoing insights in selenium research and its role in fish nutrition and fish health

In the present review, the ongoing researches about selenium research in fish nutrition have been comprehensively discussed. Selenium research is getting popularity in fish nutrition as it is required for the normal growth and proper physiological and biochemical functions in fish. Its deficiency or surplus amounts create severe problems in fish. It is available as inorganic form, organic form, and nano form. In fish, most of the previous research is about the selenium requirements for fish by using only one selenium source mainly the inorganic one. Selenium shows maximum biological activity and bioavailability when it is supplied in proper form. However, to differentiate the more bioavailable and less toxic form of selenium, sufficient information is needed about the comparative bioavailability of different selenium forms in different fish species. In fish, important data about the new forms of selenoproteins is still scarce. Therefore, it is necessary to focus on the determination and elucidation of the new selenoproteins in fish through the utilization of recent approaches of molecular biology and proteomics. The adaptation of these new approaches will replace the old fashioned methodologies regarding the selenium research in fish nutrition. Moreover, the use of molecular biology and proteomics-based new approaches in combination with selenium research will help in optimizing the area of fish nutrition and will improve the feed intake, growth performance, and more importantly the flesh quality which has a promising importance in the consumer market.