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31.
32.
Deficiency of molybdenum (Mo) in acid soils causes poor growth of pulses. An experiment was, therefore, conducted in greenhouse to study the effect of Mo, phosphorus (P), and lime application on the dry matter yield and plant Mo concentration of lentil (Lens esculenta L.) in two Mo‐deficient acid alluvial soils. The experiment was conducted using a factorial design with three levels of lime (no lime, half, and full lime requirement), three levels of P (0, 25, and 50 mg kg‐1), and two levels of Mo (0 and 1.0 mg kg‐1). Plants were grown for 60 days and at harvest their dry matter yield and Mo concentration were recorded. The three treatments significantly increased dry matter yield, Mo concentration and Mo uptake, the increase being most pronounced with Mo application followed by lime and P. Increases due to applied Mo were greater in presence than in absence of added P; while the reverse was true with the liming treatments. Liming and P application at their lower levels also interacted positively for better Mo nutrition of plants. Results thus indicated that the severity of Mo deficiency in the lentil plants may be reduced by lime and P application in Mo‐deficient acid alluvial soils. 相似文献
33.
The present study was conducted for 60 days to delineate the efficacy of various dietary immunomodulators like mannan oligosaccharide (MOS), yeast extract (YE), protein hydrolysate (PH) and chlorella (CL) in Labeo rohita fingerlings. Five hundred and eighty‐five L. rohita fingerlings (average weight: 4.15 ± 0.07 g) were randomly distributed in 13 treatment groups with each of three replicates. Thirteen semi‐purified isonitrogenous (crude protein 324.7–332.5 g kg?1) and isocaloric (17.66–17.80 MJ kg?1) diets were prepared with three graded levels (1%, 2% or 4%) of immunostimulants, except the control. At the end of the feeding trial, weight gain%, specific growth rate, feed conversion ratio, leucocyte count, erythrocyte count, haemoglobin content, serum protein, globulin, albumin–globulin ratio, nitroblue tetrazolium (NBT) value and survival percentage were evaluated. Growth was significantly higher in the MOS‐fed group. All the immune parameters studied were also recorded higher in the MOS 1%‐supplemented group. The survival percentage after challenging with Aeromonas hydrophila was higher (P<0.05) in the MOS‐, YE‐ and PH‐fed groups and the lowest in the CL‐treated group. It can be concluded that dietary supplementation of MOS at a 1% dietary level promotes growth and survival in L. rohita fingerlings. In contrast, higher inclusion levels of immunostimulants led to an immunosuppressive effect in L. rohita fingerlings. 相似文献
34.
A. S. Khehra B. S. Dhillon N. S. Nalhi S. S. Pal V. K. Saxena V. V. Malhotra 《Euphytica》1986,35(3):817-822
Summary Reciprocal recurrent selection was carried out with two populations of maize (Zea mays L.) having good combining ability. We selected for higher grain yield, early maturity, shorter plant height and lodging resistance. Two cycles were completed in two years (four seasons), by resorting to late planting of S1 lines for recombination in the main season in which top-cross families were assessed. Top-crosses and selfings were made in the off-season. The original and improved versions of the populations and their crosses were evaluated in multilocation trials. The superiority of the population hybrid was 10.3% for grain yield, 5.5% for plant height and 1.8 days to silk. The improved hybrid had delayed leaf senescence and better resistance to lodging and post-flowering stalk rots. Among the yield components, only ear girth showed improvement. Syn 2 of the improved population cross showed a yield reduction of 6.2% in comparison to Syn 1. Intrapopulation gains were not significant except for lodging resistance in one population. 相似文献
35.
The methanol extract of Rumex nepalensis Spreng. roots at the oral dose of 100-400 mg/kg exhibited significant and dose-dependent purgative activity. 相似文献
36.
A study conducted to assess the floor vegetation shows the presence of 17 species underPopulus deltoides in comparison to 28, 29 and 35 underAlbizia lebbeck, Dalbergia sissoo and mix-culture plantations, respectively. Further, the biomass and density of floor vegetation is considerably reduced underP. deltoides compared to other plantations. In addition, the indices for species richness, evenness, dominance and diversity are also
reduced underP. deltoides showing some inhibitory mechanism being operative under these plantations. Based on available literature, allelopathy is
speculated to be responsible for this reduction. 相似文献
37.
Rupinder Pal Singh Puja Srivastava Achla Sharma N. S. Bains 《Journal of Crop Improvement》2017,31(2):183-191
With continuous outbreaks of stripe rust (Puccinia striiformis f. sp. tritici) epidemics and rapid breakdown of deployed resistance in bread wheat (Triticum aestivum L.) cultivars in North West Plains Zone (NWPZ) in India warrant knowledge and deployment of new and durable sources of resistance to stripe rust. Bread wheat cultivar PBW 343, until recently the most widely cultivated wheat variety in India, is now highly susceptible to stripe rust (score 9 on a 1–9 scale), whereas PBW 621 (score 5.05–5.65) and HD 2967 (score 5.40–6.20) show low levels of resistance. We conducted an experiment, spanning three crop seasons (2013–2014 to 2015–2016), in which parental lines, F1 and F2 populations, F3 and F4 families from two bread wheat crosses, PBW 621/PBW 343 and HD 2967/PBW 343 were generated and evaluated for stripe rust resistance against a virulent pathotype. While the F1 revealed partial dominance, the segregation pattern for stripe rust resistance in F2 and F3 showed transgressive segregation for resistance in both crosses. Chi-square analysis indicated that resistant segregants possessed two genes, one contributed by PBW 621 or HD 2967 (depending on the cross) and the other, unexpectedly but obviously, came from the most susceptible cultivar, PBW 343. Possible genetic mechanisms for this residual resistance and implications for breeding programs are discussed. 相似文献
38.
The purpose of present study was to ascertain whether the response of gastrointestinal (gut) melatonin to altered feeding conditions was related to the levels of different antioxidants and digestive enzymes in the same gut tissues of a sub-tropical carp (Catla catla). Accordingly, the fish were subjected to food deprivation for 4 or 8 days and separately to re-feeding for 4 or 8 or 12 days after deprivation of food for 8 days, and their gut tissue homogenates were used to measure the levels of melatonin, both enzymatic [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST)] and non-enzymatic [reduced glutathione (GSH)] antioxidants, as well as different digestive enzymes (α-amylase, cellulase, protease, and lipase). Notably, the gut levels of melatonin, SOD, CAT, GPx, and GST underwent gradual increase with the progress of food deprivation, but a sudden fall after restoration of food supply for 4 days and a rise thereafter. Conversely, the activity of all the digestive enzymes significantly decreased after deprivation of food, but started increasing when food supply was reinforced. Gut melatonin concentrations by showing a positive correlation with the titers of different antioxidants (in both food-deprived and re-fed fish groups) and a negative (in food-deprived fish) or a positive (in re-fed fish) correlation with the activity of each digestive enzyme underlined possible physiological interplay between them. Collectively, our findings lend support to the hypothesis that gut melatonin response to altered feeding conditions in carp might be associated with the oxidative status as well as the digestive functions of the gastrointestinal tissues itself. 相似文献
39.
Sajal Pati Biplab Pal Shrikant Badole Biswapati Mandal 《Communications in Soil Science and Plant Analysis》2016,47(3):284-290
A field experiment was conducted to study the effect of silicon (diatomaceous earth, DE) fertilization on growth, yield, and nutrient uptake of rice during the kharif season of 2012 and 2013 in the new alluvial zone of West Bengal, India. Results showed that application of silicon significantly increased grain and straw yield as well as yield-attributing parameters such as plant height (cm), number of tillers m?2, number of panicle m?2, and 1000-grain weight (g) of rice. The greatest grain and straw yields were observed in the treatment T6 (DE at 600 kg ha?1 in combination with standard fertilizer practice (SFP). The concentration and uptake of silicon, nitrogen (N), phosphorus (P), and potassium (K) in grain and straw were also greater under this treatment compared to others. It was concluded that application of DE at 600 kg ha?1 along with SFP resulted increased grain, straw, and uptake of NPK. 相似文献