Soil management for Alfisols in the semiarid tropics: erosion, enrichment ratios and runoff   总被引：2，自引：0，他引：2  

A.L. Cogle  K.P.C. Rao  D.F. Yule  G.D Smith  P.J. George  S.T. Srinivasan  L. Jangawad 《Soil Use and Management》2002,18(1):10-17

Abstract. Continuous cultivation of soils of the semiarid tropics has led to significant land degradation. Soil erosion and nutrient loss caused by high runoff volumes have reduced crop yields and contributed to offsite damage. We compared a number of soil management practices (tillage, mulch and perennial/annual rotational based systems) for their potential to improve crop production and land resource protection in an Alfisol of the semiarid tropics of India. Runoff and soil erosion were monitored and surface soil and sediment were analysed for nitrogen and carbon to determine enrichment ratios. Amelioration of soils with organic additions (farmyard manure, rice straw) or rotating perennial pasture with annual crops increased soil carbon and nitrogen contents and reduced runoff, soil erosion and nutrient loss. Soil erosion totalled less than 7 t ha^–1, but enrichment ratios were often greater than 2 resulting in up to 27 kg N ha^–1 and 178 kg C ha^–1 being lost in sediment. Up to an extra 250 mm of water per year infiltrated the soil with organic additions and was available for crop water use or percolation to groundwater. The results show that there are good opportunities for reducing degradation and increasing productivity on farms.  相似文献   

Capturing genetic variability and selection of traits for heat tolerance in a chickpea recombinant inbred line (RIL) population under field conditions     

Pronob J. Paul  Srinivasan Samineni  Sobhan B. Sajja  Abhishek Rathore  Roma R. Das  Sushil K. Chaturvedi  G. R. Lavanya  Rajeev K. Varshney  Pooran M. Gaur 《Euphytica》2018,214(2):27

Chickpea is the most important pulse crop globally after dry beans. Climate change and increased cropping intensity are forcing chickpea cultivation to relatively higher temperature environments. To assess the genetic variability and identify heat responsive traits, a set of 296 F_8–9 recombinant inbred lines (RILs) of the cross ICC 4567 (heat sensitive) × ICC 15614 (heat tolerant) was evaluated under field conditions at ICRISAT, Patancheru, India. The experiment was conducted in an alpha lattice design with three replications during the summer seasons of 2013 and 2014 (heat stress environments, average temperature 35 °C and above), and post-rainy season of 2013 (non-stress environment, max. temperature below 30 °C). A two-fold variation for number of filled pods (FPod), total number of seeds (TS), harvest index (HI), percent pod setting (%PodSet) and grain yield (GY) was observed in the RILs under stress environments compared to non-stress environment. A yield penalty ranging from 22.26% (summer 2013) to 33.30% (summer 2014) was recorded in stress environments. Seed mass measured as 100-seed weight (HSW) was the least affected (6 and 7% reduction) trait, while %PodSet was the most affected (45.86 and 44.31% reduction) trait by high temperatures. Mixed model analysis of variance revealed a high genotypic coefficient of variation (GCV) (23.29–30.22%), phenotypic coefficient of variation (PCV) (25.69–32.44%) along with high heritability (80.89–86.89%) for FPod, TS, %PodSet and GY across the heat stress environments. Correlation studies (r = 0.61–0.97) and principal component analysis (PCA) revealed a strong positive association among the traits GY, FPod, VS and %PodSet under stress environments. Path analysis results showed that TS was the major direct and FPod was the major indirect contributors to GY under heat stress environments. Therefore, the traits that are good indicators of high grain yield under heat stress can be used in indirect selection for developing heat tolerant chickpea cultivars. Moreover, the presence of large genetic variation for heat tolerance in the population may provide an opportunity to use the RILs in future-heat tolerance breeding programme in chickpea.  相似文献   

Fish population and behavior revealed by instantaneous continental shelf-scale imaging     

Makris NC  Ratilal P  Symonds DT  Jagannathan S  Lee S  Nero RW 《Science (New York, N.Y.)》2006,311(5761):660-663

Until now, continental shelf environments have been monitored with highly localized line-transect methods from slow-moving research vessels. These methods significantly undersample fish populations in time and space, leaving an incomplete and ambiguous record of abundance and behavior. We show that fish populations in continental shelf environments can be instantaneously imaged over thousands of square kilometers and continuously monitored by a remote sensing technique in which the ocean acts as an acoustic waveguide. The technique has revealed the instantaneous horizontal structural characteristics and volatile short-term behavior of very large fish shoals, containing tens of millions of fish and stretching for many kilometers.  相似文献   

A consideration of previously uncharacterized fowl poxvirus unidirectional and bidirectional late promoters for inclusion in homologous recombinant vaccines     

Srinivasan V  Schnitzlein WM  Tripathy DN 《Avian diseases》2003,47(2):286-295

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Genetic Abnormalities in a Calf with Congenital Increased Muscular Tonus          下载免费PDF全文

N. Wiedemar  A.‐K. Riedi  V. Jagannathan  C. Drögemüller  M. Meylan 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(5):1418-1421

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Varietal differences in the bioaccessibility of beta-carotene from mango (Mangifera indica) and papaya (Carica papaya) fruits     

Veda S  Platel K  Srinivasan K 《Journal of agricultural and food chemistry》2007,55(19):7931-7935

Mango and papaya, which are rich sources of beta-carotene, are widely consumed in India. In this study, beta-carotene content and its bioaccessibility were determined in six locally available varieties of mango, namely, Badami, Raspuri, Mallika, Malgoa, Totapuri, and Neelam, and two varieties of papaya, namely, Honey Dew and Surya. Varietal differences were evident in both beta-carotene content and its bioaccessibility in the case of mango. beta-Carotene content in ripe mango ranged from 0.55 +/- 0.03 mg/100 g in the Malgoa variety to 3.21 +/- 0.25 mg/100 g in the Badami variety. Similarly, in the Honey Dew and Surya varieties of papaya, beta-carotene contents were 0.70 +/- 0.10 and 0.74 +/- 0.12 mg/100 g, respectively. Bioaccessibility of beta-carotene ranged from 24.5% in Badami to 39.1% in Raspuri varieties of mango. Considering both the percent bioaccessibility and the inherent beta-carotene content, the amount of bioaccessible beta-carotene was highest in the Mallika variety (0.89 mg/100 g), followed by Badami (0.79 mg/100 g). Because mango and papaya are also consumed as a blend with milk, the influence of the presence of milk on the bioaccessibility of beta-carotene from these fruits was also examined. Addition of milk generally brought about a significant increase in the bioaccessibility of beta-carotene from mango, the increase ranging from 12 to 56%. Bioaccessibility of beta-carotene from the two varieties of papaya examined was similar (31.4-34.3%). Addition of milk increased this bioaccessibility by 19 and 38% in these two varieties. Considering the beta-carotene content of mango and papaya, the latter has to be consumed in amounts roughly 3 times that of mango to derive the same amount of beta-carotene. Thus, this study has indicated that varietal differences exist in the content and bioaccessibility of beta-carotene in mango and that the addition of milk is advantageous in deriving this provitamin A from the fruit pulp of mango and papaya.  相似文献   

Estimation of genetic components of variation for salt tolerance in chickpea using the generation mean analysis     

Srinivasan Samineni  Pooran M. Gaur  Timothy D. Colmer  L. Krishnamurthy  Vincent Vadez  Kadambot H. M. Siddique 《Euphytica》2011,182(1):73-86

Chickpea (Cicer arietinum L.) is known to be salt-sensitive and in many regions of the world its yields are restricted by salinity. Recent identification of large variation in chickpea yield under salinity, if genetically controlled, offers an opportunity to develop cultivars with improved salt tolerance. Two chickpea land races, ICC 6263 (salt sensitive) and ICC 1431 (salt tolerant), were inter-crossed to study gene action involved in different agronomic traits under saline and control conditions. The generation mean analysis in six populations, viz. P₁, P₂, F₁, F₂, BC₁P₁ and BC₁P₂, revealed significant gene interactions for days to flowering, days to maturity, and stem Na and K concentrations in control and saline treatments, as well as for 100-seed weight under salinity. Seed yield, pods per plant, seeds per plant, and stem Cl concentration were controlled by additive effects under saline conditions. Broad-sense heritability values (>0.5) for most traits were generally higher in saline than in control conditions, whereas the narrow-sense heritability values for yield traits, and stem Na and K concentrations, were lower in saline than control conditions. The influence of the sensitive parent was higher on the expression of different traits; the additive and dominant genes acted in opposite directions which led to lower heritability estimates in early generations. These results indicate that selection for yield under salinity would be more effective in later filial generations after gene fixation.  相似文献   

Strange xenon, extinct superheavy elements, and the solar neutrino puzzle     

Lewis RS  Srinivasan B  Anders E 《Science (New York, N.Y.)》1977,195(4274):209-210

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Environment. Environmental monitoring network for India     

Sundareshwar PV  Murtugudde R  Srinivasan G  Singh S  Ramesh KJ  Ramesh R  Verma SB  Agarwal D  Baldocchi D  Baru CK  Baruah KK  Chowdhury GR  Dadhwal VK  Dutt CB  Fuentes J  Gupta PK  Hargrove WW  Howard M  Jha CS  Lal S  Michener WK  Mitra AP  Morris JT  Myneni RR  Naja M  Nemani R  Purvaja R  Raha S  Vanan SK  Sharma M  Subramaniam A  Sukumar R  Twilley RR  Zimmerman PR 《Science (New York, N.Y.)》2007,316(5822):204-205

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A reversibly switching surface     

Lahann J  Mitragotri S  Tran TN  Kaido H  Sundaram J  Choi IS  Hoffer S  Somorjai GA  Langer R 《Science (New York, N.Y.)》2003,299(5605):371-374

We report the design of surfaces that exhibit dynamic changes in interfacial properties, such as wettability, in response to an electrical potential. The change in wetting behavior was caused by surface-confined, single-layered molecules undergoing conformational transitions between a hydrophilic and a moderately hydrophobic state. Reversible conformational transitions were confirmed at a molecular level with the use of sum-frequency generation spectroscopy and at a macroscopic level with the use of contact angle measurements. This type of surface design enables amplification of molecular-level conformational transitions to macroscopic changes in surface properties without altering the chemical identity of the surface. Such reversibly switching surfaces may open previously unknown opportunities in interfacial engineering.  相似文献