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51.
The imbalanced use of chemical fertilizers under intensive cultivation practices over a period of years leads to various soil-associated problems particularly nutrient availability. Thus, to examine the effect of long-term application of balanced and imbalanced inorganic fertilizer and farm yard manure (FYM) application on the chemical fraction of DTPA-extractable micronutrients under rice–wheat cropping system after 29 years, the observations were recorded from the ongoing field experiment at Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, India. An application of balanced inorganic fertilizer with FYM in rice, while without FYM in wheat significantly improved the DTPA-extractable Zn, Fe, Mn and Cu after rice and wheat crops in both the surface and sub-surface soil layers. Lowest DTPA-extractable Zn, Fe, Mn and Cu were recorded, in surface and sub-surface soil under rice and wheat crops in control. The highest DTPA-extractable Zn, in both surface and sub-surface layers of rice (3.31, 1.62 mg kg−1, respectively) and wheat (2.96, 0.99 mg kg−1, respectively) was recorded because of application of N180+P80+K40+Zn(F) + FYM in rice and N180+P80+K40+Zn(F) in wheat. However, the DTPA-extractable Fe, Mn and Cu were highest in rice and wheat because of N120+P40+K40+FYM and N120+P40+K40 application, respectively. The balanced use of inorganic fertilizer with FYM (N180+P80+K40+Zn(F) + FYM) in rice and without FYM [N180+P80+K40+Zn(F)] in wheat supported the highest rice (6.74 t ha−1) and wheat (3.50 t ha−1) grain yields, while lowest in control. Based on the study results, long-term application of FYM at 5 tonnes ha−1 in rice crop sustained the availability of DTPA-extractable cationic micronutrients to rice and wheat in Mollisols.  相似文献   
52.
A study was conducted to evaluate the effect of an immunostimulant product prepared from vibrio bacterial components on production of Penaeus monodon culture in five commercial shrimp farmer’s ponds in the Navsari district of Gujarat. The product was administered at the concentration of 2 × 108 cfu/kg pelleted feed as top dressing using a commercial binder for two consecutive days in a week. In general, we observed improvement of up to 33.33% in average body weight, up to 44.83% in survival rate, up to 11.11% in FCR, and up to 50.00% in production per ha over untreated control ponds on the same farm. Administration of this vibrio bacterial product could improve shrimp production in Gujarat.  相似文献   
53.
We have reported the molecular characterization including gene silencing, superoxide activity, superoxide anion production, gene expression and molecular characterization of a mitochondrial manganese superoxide dismutase (mMnSOD) from striped murrel Channa striatus (named as CsmMnSOD). The CsmMnSOD polypeptide contains 225 amino acids with a molecular weight of 25 kDa and a theoretical isoelectric point of 8.3. In the N-terminal region, CsmMnSOD carries a mitochondrial targeting sequence and a superoxide dismutases (SOD) Fe domain (28–109), and in C-terminal region, it carries another SOD Fe domain (114–220). The CsmMnSOD protein sequence shared significant similarity with its homolog of MnSOD from rock bream Oplegnathus fasciatus (96 %). The phylogenetic analysis showed that the CsmMnSOD fell in the clade of fish mMnSOD group. The monomeric structure of CsmMnSOD possesses 9 α-helices (52.4 %), 3 β-sheets (8.8 %) and 38.8 % random coils. The highest gene expression was noticed in liver, and its expression was inducted with fungal (Aphanomyces invadans) and bacterial (Aeromonas hydrophila) infections. The gene silencing results show that the fish that received dsRNA exhibited significant (P < 0.05) changes in expression when compared to their non-injected and fish physiological saline-injected controls. The SOD activity shows that the activity increases with the spread of infection and decreases once the molecule controls the pathogen. The capacity of superoxide anion production was determined by calculating the granular blood cell count during infection in murrel. It shows that the infection influenced the superoxide radical production which plays a major role in killing the pathogens. Overall, this study indicated the defense potentiality of CsmMnSOD; however, further research is necessary to explore its capability at protein level.  相似文献   
54.
In total 36 superior clones of Dalbergia sissoo Roxb., screened from 300 selections conducted in natural and growing range of India and Nepal, were multiplied using single nodal cuttings and established to evaluate genotype×environmental interactions for adaptability and stability at the age of 30 months in three geographical locations in the state of Punjab, India. Clone 124 had maximum adaptability and stability (bi = 1.04) to perform exceedingly well over the locations. Clones 36 and 1 were stable with mean regression coefficient of 0.84 and 1.22, respectively. Nonetheless, clone 41 performed exceedingly well for all the characters to attain maximum population mean, and the performance varied substantially across the locations. Therefore, clone 41 was considered as productive but non-adaptive clone. Though some of the clones were sensitive to sites, 14 clones for height, 16 for collar diameter, 12 for DBH and 7 for volume were relatively un-sensitive with higher regression coefficient. Nonetheless, clone 124 was the most stable with average bi value of 1.04 and productive, which could play an important role in future breeding and commercial deployment of stable and productive planting stock of Dalbergia sissoo.  相似文献   
55.
56.
Leaf litter decomposition is a critical step in nutrient cycling and providing nutrients to plants. Decomposition of dry matter, lignin, ligno-cellulose, cellulose and polyphenols was investigated in relation to nitrogen (N), phosphorus (P) and potassium (K) dynamics in leaf litter of mango, guava and litchi orchards under hot and dry sub-humid climate. Leaf litter of mango and guava decomposed more rapidly than that of litchi with decay constants of 3.22, 1.33 and 0.62 yr-1, respectively. The leaf litter organic substances like polyphenol lost more rapidly followed by cellulose, lignin and ligno-cellulose throughout the period of decomposition. The N was released faster both in mango and guava with decay constant of 4.06 and 2.11 yr-1, respectively. The release of K was faster in mango followed by guava and litchi with decay constant of 4.66, 3.18 and 1.63 yr-1, respectively. The leaf litter decomposition was significantly positively correlated with soil fungal and bacterial biomass, rainfall and air temperature, while the leaf chemistry showed significant negative correlations in all the orchards. The results demonstrated that mango leaf litter was found to be the best followed by guava, and litchi in terms of N, P, and K return in less period of time.  相似文献   
57.
Nutrient utilization, body condition and carcass traits of cull ewes were studied in three dietary regimens based on complete feed block (CFB) feeding to control (C) with rumen protected protein (RPP), CU [RPP + urea (6 g/kg)] and CUF [RPP + urea + rumen protected fat (RPF; 40 g/kg)]. The RPP component (g/kg) in C had 1% formaldehyde‐treated soy flakes 50, mustard cake 50 and sesame cake 30. The mustard and sesame cakes were replaced with urea on equivalent N basis in CU and CUF. The ewes were offered ad libitum CFB composed (g/kg) of concentrate 650, roughage 300 and molasses 50. The digestibility of OM and EE was higher (p < 0.05) in CUF than in CU and C, while that of NDF and ADF was lower (p < 0.05). The CP digestibility was higher in both CU and CUF. Utilization of N and Ca was higher (p < 0.05) in CUF compared with C and CU. Urinary purine derivatives analysis and microbial N synthesis were similar in all the groups. Blood glucose concentration improved at 90 day compared with 0 day. Ruminal attributes showed a higher (p < 0.05) pH, total N, TCA precipitable N, entodiniomorphs and total ciliate population in CU and CUF than in the control. The CUF had higher (p < 0.01) DM, digestible OM and ME intake, which resulted in higher (p < 0.05) weight gain and better feed efficiency. Ewes in all the groups showed an improvement in carcass traits at 90 day. The pre‐slaughter weight was higher (p < 0.05) and dissected and KOH bone content was lower in CUF. Thus, feeding of CFB with urea as a cheaper N source and RPF to enrich with energy supported the improved performance as evidenced from higher nutrient input, ‘utilization and efficiency with enhanced carcass traits’ for better marketability and returns from cull ewes.  相似文献   
58.
对印度喜马拉亚东部3个州的经济竹种的分布、生长和生产力进行了研究。在梅加拉亚那邦,发现了牡竹属、巴苦竹和梨竹属3个经济竹种。巴苦竹是在米佐拉姆的记载,方竹属和牡竹属是在锡金记载的笋用竹。所有竹种除野生外均在庭院中栽培。据观察,竹子的产量与海拔的变化密切相关,巴苦竹最大产量出现在低海拔的而非高海拔的林分中。牡竹在梅加拉亚邦每丛生长69株,每公顷1839株,大大高于庭院种植的低海拔株数(每丛16株,每公顷303株)。而在天然林中,在高海拔总株数为每丛29株,每公顷1186株,在低海拔中每丛22株,每公顷178株。  相似文献   
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60.
Crotalaria tetragona Roxb. ex Andr., locally known as “Tum-thang” was collected from Mizoram state of north-eastern hill region of India during 2008. Its flowers were being sold by the tribal communities in local markets. The buds and flowers are cooked as vegetables and used in garnishing of local food preparations especially in non-vegetarian recipes. This species is reported here as little known Edible type in Indian region and may be considered as a multi-purpose species with potential. Edible uses of some of the Crotalaria species in different regions of world have also been included in the present communication.  相似文献   
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