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51.
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Effects of VC application on tomato production and media properties can last for the third successive season, which was verified in this study to evaluate effects of VC application on growth, productivity and fruit quality of cherry tomato for the third season. Six treatments were designed similarly in the first and second seasons (unchanged design compared to the previous season), including: VC with rice husk ash (RHS) and coconut fiber (CF) 0% VC+ 50% RHS +50% CF (T1- control), respectively. 20%VC + 40% RHS + 40% CF(T2), 40% VC+ 30% RHS + 30% CF(T3), 60% VC + 20% RHS + 20% CF(T4), 80% VC + 10% RHS + 10% CF(T5), and 100% VC(T6). The results showed that the pH, EC, N, P, K, Ca, and Mg available in media were increased with the addition of VC. This finding revealed that the addition of VC significantly improved the physic-chemical media properties, increasing the EC and also increasing the macronutrients in the media resulting in substantial increased the yield and quality of tomato fruits. It is concluded that EC of VC was the key factor for the positive increase of the productivity and quality of tomato and the salinity (EC at 3.52 dS/m) causing restriction of water to fruits that resulted in the increase of the total soluble solids in tomato fruit and without affecting yield reduction.  相似文献   
53.
In the first and second seasons, growth and yield of tomato were also influenced by different vermicompost (VC) rates and reused VC. Obviously, increasing VC proportion led to the augmentation of electrical conductivity (EC), nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) in planting media in both seasons. However, in the first season, the nutrient absorbent ability of tomato was remarkably higher compared to those in the second season due to higher available nutrient in the media of the first season. This may influence the shoot dry weight as well as the yield of tomato in both seasons. In T4 treatment, the yield attained the highest value in the first season for both varieties with the values of 562.3 and 812.4 g/plant for small honey (V1) and graces (V2), respectively. In the second season, the N, P, K, Ca, and Mg in media significantly decreased compared to those in the first season (496.4 g/plant-V1 and 508.3 g/plant-V2). In comparison, the yields in the first season were higher those in second season by 13.2% and 59.8% for V1 and V2, respectively. However, in the second season, the maximum yield found in T5 (508.3 g/plant-V1 and 682.2 g/plant-V2) and declining by 10.6 and 19.1% compared to those in the first season for V1 and V2, respectively. This can be explained that amounts of nutrients from the media in the first season had supported the growth and development of tomato, resulting deficiency of nutrients in the media for the second season.  相似文献   
54.
This study aimed to examine the effects of ethanol-soluble components (Es) in soybean meal (SBM) on gut content transit, bile acid (BA) and pancreatic digestive enzyme secretions, nutrient apparent digestibility coefficients (ADC), liver and intestinal morphologies, and growth performance of pompano (Trachinotus blochii). The SBM was extracted with aqueous ethanol, then the supernatant and residue were separated and dried to produce ethanol-extracted SBM (ESBM) and the Es. Four experimental diets were formulated with fish meal (FM), ESBM and SBM as main dietary protein sources. The diets were denoted as follows: FMD (FM diet), SBMD (SBM diet), ESBMD (ESBM diet) and ESBM + EsD (ESBM plus Es diet). Thirty-five fingerling pompano with an initial body weight (BW) of 18.3 g were allocated to each of 12 polyvinyl chloride tanks (1000-L holding capacity), resulting in triplicate tanks per dietary treatment. For 10 weeks, the fish were hand-fed the experimental diets to apparent satiation twice daily. The results showed that the final BW, weight gain and specific growth rate were significantly lower, while the feed conversion ratio was higher in the SBMD and ESBM + EsD groups than in the ESBMD and FMD groups (p < 0.05). Fish fed SBMD and ESBM + EsD showed accelerated gastric transit, slowed intestinal mobility, and lowered secretions of BAs and pancreatic digestive enzymes as compared to those fed ESBMD and FMD. Morphological abnormalities in mucosal folds of the posterior intestine, but not the liver, were clearly observed in the SBMD and ESBM + EsD groups. These results indicated that the Es in SBM inhibited the digestive system, leading to decreased nutrient digestibility and growth performance in pompano. The findings of the present study suggested that removal of the Es would effectively improve the nutritional quality of SBM and enhance growth performance of pompano fed a SBM-based diet.  相似文献   
55.
The objective of this study was to evaluate the effect of supplementation of varying levels of cassava root meal (CRM, 300 and 1,000 g), without or with 700 g groundnut cake (GNC) on intake and performance of growing Laisind cattle fed with a basal diet of urea-treated rice straw (URTRS). Twenty-four male cattle of crossbred Laisind (50 % Red Sindhi and 50 % local Yellow, both Bos indicus), from 15 to 17 months of age, 165–175 kg body weight, were used. They were assigned to a completely randomized block design in a 2?×?2 factorial arrangement (two CRM levels and two GNC levels). Intake of URTRS (interaction, P?<?0.01) and digestibility of neutral detergent fiber (interaction, P?<?0.05) decreased as CRM level increased on the diets without GNC but was not affected by CRM level on the diets with GNC. The total dry matter intake (interaction, P?<?0.05) and live weight gain (LWG) (interaction, P?<?0.001) increased as CRM level increased on the diets with GNC, but no difference was observed on the diets without GNC. In conclusion, supplementation of 1,000 g CRM should be in combination with 700 g GNC to avoid the negative effects on URTRS intake and digestibility, therefore improving LWG of growing Laisind cattle fed on a URTRS-based diet.  相似文献   
56.
Arnon TI  Xu Y  Lo C  Pham T  An J  Coughlin S  Dorn GW  Cyster JG 《Science (New York, N.Y.)》2011,333(6051):1898-1903
Lymphocytes egress from lymphoid organs in response to sphingosine-1-phosphate (S1P); minutes later they migrate from blood into tissue against the S1P gradient. The mechanisms facilitating cell movement against the gradient have not been defined. Here, we show that heterotrimeric guanine nucleotide-binding protein-coupled receptor kinase-2 (GRK2) functions in down-regulation of S1P receptor-1 (S1PR1) on blood-exposed lymphocytes. T and B cell movement from blood into lymph nodes is reduced in the absence of GRK2 but is restored in S1P-deficient mice. In the spleen, B cell movement between the blood-rich marginal zone and follicles is disrupted by GRK2 deficiency and by mutation of an S1PR1 desensitization motif. Moreover, delivery of systemic antigen into follicles is impaired. Thus, GRK2-dependent S1PR1 desensitization allows lymphocytes to escape circulatory fluids and migrate into lymphoid tissues.  相似文献   
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