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1.
Plant Foods for Human Nutrition - Emerging data support that plant food based isoflavones have ameliorating effects on a variety of neurodegenerative diseases including Parkinson’s disease...  相似文献   
2.
This study was carried out in farmers' fields to quantify the total water and consumptive water use in grow‐out culture of Penaeus monodon under recommended package of practice with two different water management protocols: T1, with no water exchange and T2, with regulated water exchange. Treatment‐wise estimated total water use, was 2.09 and 2.43 ha‐m 122 day?1, while the computed consumptive water use index (m3 kg?1 biomass) was 5.35 and 6.02 in T1 and T2 respectively. Lower rates of water exchange (T2) showed significantly improved (P < 0.05) crop performance in terms of performance index (19.75 ± 0.75), production‐size index (74.1 ± 3.4), survival rate (80.13 ± 1.7%) and productivity (2.44 ± 0.08 t) over the zero water exchange. The shrimp pond water quality suitability index (WQSI) infers that regulated water exchange (T2) improved the overall suitability of water quality for shrimp culture. WQSI up to 90 days of culture ranged between 7.5–9.0 in T2, needs little management while in the last month of rearing, it was good with moderate management requirements. Treatment‐wise sediment load ranged between 50.4–56.3 m3 t?1 shrimp biomass. High intensity of water exchange and low apparent feed conversion ratio influenced in lowering the sedimentation rate. Regulated water exchange protocol (T2) performed well (higher net total water productivity and net consumptive water productivity) against no water exchange (T1). A higher OV:CC ratio (ratio of the output value to the cost of cultivation) indicated that T2 had a distinct edge over the T1 protocol.  相似文献   
3.
Vyas D  Kumar S  Ahuja PS 《Tree physiology》2007,27(9):1253-1259
Tea (Camellia sinensis (L.) O. Kuntze) is a perennial crop grown throughout the world. During winter, tea undergoes a dormancy period when growth of apical buds almost ceases, severely reducing the commercial yield of tea. Low temperatures prevail during the period of winter dormancy, which alone or in combination with high solar irradiance have the potential to induce oxidative stress in plants. We studied six tea clones under field conditions to test whether a relationship exists between oxidative stress and winter dormancy. Data on the behavior of the enzymatic antioxidative system was collected for all clones during different phases of winter dormancy. There was a strong positive correlation among clones between accumulation of reactive oxygen species (ROS) and the length of the dormancy period. Clones having shorter dormancy periods exhibited higher induction of antioxidative enzymes. Results suggest that efficient scavenging of ROS is a desirable feature in tea because it leads to lower accumulations of ROS during winter months and is associated with reduced winter dormancy.  相似文献   
4.
Helopeltis theivora Waterhouse (Heteroptera: Miridae) is a major sucking insect pest of tea (Camellia sinensis) which feeds on a wide variety of alternative host plants. Feeding biology and fitness traits of H. theivora, on two alternative host plants, viz., Mikania micrantha (Asteraceae) and Psidium guajava (Myrtaceae), besides C. sinensis (Theaceae), were studied along with corresponding levels of xenobiotic defense enzymes. C. sinensis is the preferred host of H. theivora. The development time of H. theivora is significantly shorter on C. sinensis (13.3?±?0.16?days) than on the two other hosts, M. micrantha (14.2?±?0.22?days) and P. guajava (14.7?±?0.23?days). Similarly, the fecundity (C. sinensis: 172.6?±?4.5 eggs/female, M. micrantha: 128.6?±?4.4 eggs/female, P. guajava: 118.7?±?3.3 eggs/female), oviposition period (C. sinensis: 24.1?±?0.7?days, M. micrantha: 22.5?±?0.6?days, P. guajava: 21.7?±?0.8?days) and hatchability (C. sinensis: 80.9?±?1.9%, M. micrantha: 69.4?±?1.6%, P. guajava: 64.1?±?1.7%) are recorded to be significantly higher on C. sinensis. The age at reproductive maturity and egg incubation periods were lower on C. sinensis than on the two other host plants. Host-based variation in H. theivora fitness traits is interpreted in light of differential activity of three principal xenobiotic detoxifying enzymes, the general esterases (GEs), glutathione S-transferases (GSTs) and cytochrome P450 monooxygenases (CYPs). The activities of these enzymes in H. theivora were significantly enhanced when the insect fed on M. micrantha and P. guajava as compared with on C. sinensis.  相似文献   
5.
Climate change, deforestation and over reliance on chemical pesticides during the last five decades are presumed to have had a significant impact on the incidence and abundance of agricultural pests. The thrips (Scirtothrips dorsalis Hood) and the greenfly (Empoasca flavescens Fabricius), which were previously considered as minor or occasionally as serious pests in localized areas of tea plantations, are now established as regular and at times major pests in tea plantations of North Bengal spread over the sub Himalayan slopes and the adjoining plains of Terai and the Dooars. Tea-planters from different pockets of North Bengal have been repeatedly reporting control failures of these pests with the use of insecticides in recommended dilutions. A study of their seasonal incidence along with activity of detoxifying enzymes was considered. The trend of a recent population study revealed that E. flavescens and S. dorsalis were abundant throughout the year, with peaks during April to June. Abiotic factors such as temperature, rainfall, sunshine hours and relative humidity (afternoon) influenced the population abundance. Insecticide-exposed populations showed higher levels of activity of the detoxifying enzymes than those collected from organic plantations and the laboratory-reared populations that had not been exposed to insecticides. Detoxifying enzymes in insecticide-exposed E. flavescens collected from Terai and the Dooars as compared with laboratory control specimens showed 3.0–5.2 and 3.0–9.7-fold increases in general esterases (GEs), 1.5–4.8 and 3.6–5.3-fold increases in cytochrome P450s (CYPs) and 1.2–3.5 and 1.5–2.5-fold increases in glutathione-s-transferases (GSTs), respectively. Similarly, S. dorsalis collected from Terai and the Dooars showed 2.0–6.0 and 2.3–5.6-fold increases in GEs, 1.5–2.3 and 1.6–2.4-fold increases in CYPs and 2.6–3.7 and 2.3–3.6-fold increases for GSTs, respectively. Bands of isozymes of esterase I–VI and I–V were found to be expressed in insecticide-exposed specimens whereas a negligible expression was evident for the bands in unexposed E. flavescens and S. dorsalis of organic plantations and laboratory-reared origins, respectively. The data obtained in the present study would be useful in developing the integrated resistance management strategies leading to effective management of the said pests.  相似文献   
6.
Journal of Soils and Sediments - In this study, the effectiveness of in situ sediment capping was investigated as a remediation option for total mercury (THg) and methylmercury (MeHg) in the...  相似文献   
7.
The present investigation involved 261 Holstein Friesian (HF) × Sahiwal cows to study the udder health as well as the udder and teat morphometry. The udder health was defined on the basis of bacteriology and California mastitis test of quarter foremilk. The morphometry parameters included udder fore depth (UFD, distance from the point where the fore udder merges within the abdomen to a point in front of the fore teats at the level of the udder base), udder rear depth (URD, distance from the bottom of the vulva to the base of the rear udder), udder depth (UD, level of the udder base with respect to hock joint), height of the udder from the floor, teat length, teat diameter (at mid of the teat barrel), teat-tip to floor distance and distance between the teats. The URD, UD and height of udder from the floor showed a significant (P?<?0.05) relation to the udder health with mastitic cows having larger URD, smaller udder distance from the floor and the udder base placed below the hock joint. The cows with teat length larger than 4.5 cm and teat diameter 3.0 cm or larger had significantly more quarters affected with mastitis. Further, cows with teats placed nearer to the floor were more susceptible to mastitis (P?<?0.01). No significant differences were found between healthy and mastitic udders with respect to UFD and distance between teats. It can be concluded that selection for optimum udder and teat morphometry in breeding programmes may help to reduce susceptibility to intramammary infections in HF × Sahiwal cows.  相似文献   
8.
Genetic Resources and Crop Evolution - Indian mustard [Brassica juncea (L.) Czern.] is a major edible oil crop of India. The Indian Council of Agricultural Research—National Bureau of Plant...  相似文献   
9.
This study was designed to quantify the total water requirement and consumptive water use in carp‐prawn polyculture system under different water management protocols, using water balance model. Under different water management protocols, treatment‐wise estimated total water use, TWU (×104, m3) was 3.7, 4.6 and 3.9, while the computed consumptive water use index, CWUI (m3 kg?1 biomass) was 6.62, 9.31 and 7.08, in T1 (no water exchange), T2 (periodic water exchange) and T3 (regulated water exchange) respectively. Significantly higher yield (P < 0.05) in both T2 and T3 over T1, was probably due to water exchange that improved the rearing environment. Although intensity of water exchange was more in T2, significant variation (P < 0.05) in overall growth and yield was not recorded between T2 and T3. Treatment‐wise sediment load ranged between 54.6 and 71.3 m3 t?1 biomasses. Higher sediment load was recorded at lower intensity of water exchange as well as with higher apparent feed conversion ratio. Higher net total water productivity, net consumptive water productivity and OV‐CC ratio in T3 infers that regulated water exchange has a distinct edge over the no water exchange protocol. Restricted water use instead of regular/excess water exchange not only improves the production performance and water productivity, but also helps in lessening the operational pumping cost.  相似文献   
10.
Gmelina arborea is an important timber-yielding tree that grows naturally in the tropical and subtropical regions of Southeast Asia and has also been introduced as a plantation species outside these regions. Genetic diversity in this tree species was observed in stone/seed-related traits and in vitro responses of cultured nodal segments from plants of eight different populations representing natural forests, fragmented forests and plantations. Variance analysis showed significant differences between populations for these traits. However, it was not possible to separate the different populations using these traits by multivariate analysis, even after environmental variation was reduced over six subcultures. Genetic diversity was therefore analysed using molecular markers. Inter-simple sequence repeat (ISSR) primers yielded 95% polymorphic loci among the eight populations and UPGMA analysis enabled separation of these populations on the basis of their genetic distances. Diversity was also analyzed using population genetics parameters like Nei’s genetic diversity and gene differentiation. Nei’s genetic diversity was 0.29 between populations and 0.11 within populations. AMOVA analysis indicated 41 and 59% within- and between-population genetic diversity, respectively. Mantel test suggested that genetic differentiation between six Indian populations was positively correlated to geographic distance (r = 0.626, P = 0.029). Assessment of the genetic variation in G. arborea populations is an important step in selection of conservation strategies for this species since diversity forms the basis for species adaptation.  相似文献   
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