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131.
Rice (Oryza sativa L.)-dominated rainfed uplands of eastern India are facing two major problems such as lack of irrigation water sources and low productivity. In fact, unlined on-farm pond (OFP) technology in this terrain could prove to be an effective agricultural drought mitigation measure for monsoon crops but failed to ensure supplemental irrigation (SI) to the next winter crops. Consequently, the OFP technology could not pick up in the region. In order to overcome the shortcomings in the technology, the location of the OFP has been changed and a new concept of partial rice substitution (PRS) has been introduced in the present study to provide SI for the second crop in winter. Maize (Zea mays L.) and rice crops at upper and lower compartments of the field, respectively, were tried at various crop substitution ratios (CSR) of 70:30, 60:40, 50:50, 40:60, and 30:70 during monsoon season. Rainfall excess from both the compartments was harvested in an unlined OFP located in between the compartments and used for providing SI. In winter, black gram (Vigna mungo L.) and mustard (Brassica campestris) were taken in the upper and lower compartments, respectively, based on availability of water in the OFP. Water balance models were used to simulate the soil moisture in crop root zone as well as storage of water in the OFP. The optimal size of such unlined OFP for average land holdings (1200 m2) in rainfed uplands and under 60:40 CSR was found to be occupying 6 % area of the crop field. 相似文献
132.
Summary Crosses between a wild species C. chacoense and three cultivated species of chili pepper viz. C. annuum, C. frutescens and C. chinense yielded hybrids when C. chacoense was the seed parent but the reciprocal crosses were unsuccessful. C. chacoense × C. annuum F1 hybrids were partly fertile and therefore an F2 population could be raised; the other two F1 hybrids were totally sterile. Chromosome pairing in the F1 plants resulted largely in bivalents and a few multivalents and univalents. The genomes of the four species share large homologies and the role of chromosome structural changes in genome differentiation is suggested. Hybrid sterility is the major reproductive isolation mechanism. 相似文献
133.
This study documents wild food species in a locally managed forest by the inhabitants of nine villages in the Dolakha district,
Nepal. It presents data on their diversity, and traditional knowledge on plant use, propagation and local domestication collected
through household and key informant interviews, forest transects inventories and herbaria verifications. Sixty-two wild food
plants belonging to 36 families were recorded; most of them (80%) have multiple uses. Many of the food plants are herbaceous
(24 species) and produce fruits for consumption (46%). Most of the food plants are consumed by the local communities as snacks,
and are supplementary and nutritionally important especially prior to the harvest of staple foods. Elder women (>35 years)
are the most knowledgeable group, being able to describe the use of 65% of all edibles as compared to only 23% described by
young men (<35 years). Many villagers also possess knowledge on the modes of propagation for the food plants that may be used
in the process of domestication. The local communities expressed a strong desire for the establishment of community enterprises
based on the wild food resources for long-term income generation sources. To accomplish this, development of collective co-operative
strategies based on assessments of the biology, size of harvestable population, sustainable harvesting techniques, and marketing
value and demand of promising species would be required. Moreover domestication potential based on species identified in this
paper and other species that local communities have knowledge on ought to be encouraged through incentive and policy interventions. 相似文献
134.
Spatio-temporal differences under short-term NaCl-salinity (0, 50, 100, 150 m m l−1 ) stress for 24 h and post-NaCl recovery after 24 h on the growth, water relations, ionic composition, proline and antioxidants of 12-day-old roots, stem and leaves of Vigna radiata were observed. Fresh and dry weight, relative water content and K+ ion decreased, whereas, Na+ ion and Na+ /K+ ratio increased significantly in roots, stem and leaves. Post-NaCl recovered roots, stem and leaves showed similar results with lower values. Chlorophyll and carotenoid pigments decreased significantly in the leaves. Peroxide and lipid peroxidation level increased significantly with higher ratio in stressed compared to recovered leaves. Ascorbate and proline content increased significantly with no significant change in glutathione content in stressed roots, stem and leaves. Significant decrease in protein content, SOD, CAT, POX, APX and GR activities was observed in roots with no significant change in stem and leaves. The recovered parts showed similar results except increased POX and GR activities showing a tissue-specific response to NaCl-salinity stress. Improved tolerance to salt stress may be accomplished by increased capacity of antioxidative defence system and by lower level of lipid peroxidation and improvement in the plant water status, activities of some of the antioxidants in the recovered parts suggest that significant tissue differences in response to salt stress in V. radiata is closely related to differences in the activities of antioxidants, ion and proline content. 相似文献
135.
Kristina Hiney Lara Sypniewski Pratyaydipta Rudra Adel Pezeshki Dianne McFarlane 《Journal of animal science》2021,99(6)
The interest and demand for healthy and less processed foods for human consumption have been mirrored in the pet industry, with an explosion of alternative diets available. Several nontraditional feeding methodologies including raw meat-based diets (RMBDs) are believed by many dog owners to be superior to traditional extruded commercial dog foods. Despite the strong opinions, limited data are available comparing objective health measures among healthy dogs fed using different methods of diet preparation. Therefore, we compared health markers in client-owned dogs fed an RMBD to markers in dogs fed a high-quality extruded kibble. We hypothesized that healthy adult dogs fed RMBD would show differences in biochemical and hematological parameters and improved clinical health scores (e.g., dental, external ear canal, and integument scores) compared with dogs fed a kibble diet. A cross-sectional observational study was performed comparing hematology, serum biochemistry, urinalysis management history, and clinical health scores in healthy client-owned dogs reported as fed RMBD (n = 28) or kibble (n = 27) for >1 yr. Dental, external ear canal, and integument health scores were assigned by a single veterinary evaluator blinded to feed group, using a scale where 0 was normal and 3 was most severely affected. Spearman correlation coefficient (rs) was calculated to assess the strength and direction of the relationship of biochemical outcomes with age and body condition score (BCS), while analysis of variance was used to determine if biochemical analytes differed by breed or gender. Biochemical data were analyzed using multiple linear regression models, adjusting for the covariates gender, breed, age, and BCS. A composite clinical health score, (CCS) = 9 − (dental score + otitis score + integument score), was compared between feeding groups using Mann–Whitney test. Serum alkaline phosphatase activity (P < 0.001) and globulin concentration (P < 0.001) were lower, while lymphocyte count (P < 0.05) was higher in dogs fed RMBD. No differences were found in urinalysis between diet groups. Dogs fed RMBD showed a slight improvement in CCS compared with kibble-fed dogs (CCS: P = 0.03). Owner management significantly differed with a greater likelihood of management interventions including dietary supplements and sporting activities in the RMBD group. Further work is needed to specifically determine the impact of diet processing and nutrient content on canine health. 相似文献
136.
137.
138.
富马海松酸的制备(英文) 总被引:4,自引:2,他引:2
介绍了山乔松(印度兰松)(Pinus wallichiana)松脂直接制备富马海松酸(FPA)的二种实验室方法:(1)松脂200克、富马酸20克、乙醇1000毫升置三颈瓶中混合并回流48小时,静置过夜、减压吸滤分离出粗FPA,冷乙醇洗数次得纯FPA晶体,190~230℃真空干燥3小时,得率48%,酸价420,熔点295~298℃,[α]D(CHCl_3)±42.5~0;(2)松脂200克、富马酸35克置三颈瓶中在220—225℃下激烈搅拌3小时,由冷却器收集松节油,瓶中粗FPA冷却后加入苯、乙醇混合液(15:85)500毫升,混匀过夜,减压吸滤分离出粗FPA,以冰冷苯、乙醇(15:85)混合液洗数次,得纯FPA纯白色晶体,190—230℃真空干燥2.5小时,得率42%,酸价420,熔点285—287℃,[α]D(CHCl_3)+42.7℃。 纯FPA作了红外、核磁共振、质谱和气液色谱仪器分析予以证实。 相似文献
139.
Cameron RG Luzio GA Vasu P Savary BJ Williams MA 《Journal of agricultural and food chemistry》2011,59(6):2717-2724
Methyl ester distribution in pectin homogalacturonan has a major influence on functionality. Enzymatic engineering of the pectin nanostructure for tailoring functionality can expand the role of pectin as a food-formulating agent and the use of in situ modification in prepared foods. We report on the mode of action of a unique citrus thermally tolerant pectin methylesterase (TT-PME) and the nanostructural modifications that it produces. The enzyme was used to produce a controlled demethylesterification series from a model homogalacturonan. Oligogalacturonides released from the resulting demethylesterified blocks introduced by TT-PME using a limited endopolygalacturonase digestion were separated and quantified by high-pressure anion-exchange chromatography (HPAEC) coupled to an evaporative light-scattering detector (ELSD). The results were consistent with the predictions of a numerical simulation, which assumed a multiple-attack mechanism and a degree of processivity ~10, at both pH 4.5 and 7.5. The average demethylesterified block size (0.6-2.8 nm) and number of average-sized blocks per molecule (0.8-1.9) differed, depending upon pH of the enzyme treatment. The mode of action of this enzyme and consequent nanostructural modifications of pectin differ from a previously characterized citrus salt-independent pectin methylesterase (SI-PME). 相似文献
140.
R. Raja A.K. Nayak B.B. Panda B. Lal Rahul Tripathi Mohammad Shahid 《Archives of Agronomy and Soil Science》2013,59(12):1701-1715
The dynamics of meteorological drought and its relationship with block level rice productivity over the Eastern Indian state of Odisha was assessed during the wet season (June to November) using the standardized precipitation index (SPI). The time series of rainfall data (1983–2008) from 168 rain gauge stations was used to derive the 1- and 3-month SPI of different wet season months. The 1- and 3-month SPI data were interpolated to map spatial patterns of meteorological drought and its severity, and the maps of a drought (2008) and normal (2007) year were discussed in detail. Further, the time series of SPI was exploited to assess the drought risk in Odisha. Correlation analysis of 1- and 3-month SPI with rice productivity index (RPI) showed that the SPI of 1-month time scale particularly in July (r = 0.49) and October (r = 0.33) had significantly stronger relationship with RPI than any of the 3-month SPI individually during wet season. The cumulative degree of severity of drought could be better explained by 3-month SPI map when drought events are well spread in the preceding months. Regression models were developed using 1- and 3-month SPI for forecasting rice productivity of blocks with varying proportion of rainfed area in Odisha. Model developed based on 1-month SPI accounted for 27% yield variability in rice and could be used for forecasting rice productivity. 相似文献