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51.
Phytoparasitica - Zeugodacus cucurbitae (Coquillett) is an economically significant destructive pest of many vegetable and fruit crops. Peptidase inhibitors are a class of plant proteins that cause...  相似文献   
52.

Cytoplasmic male sterility (CMS) system has been exploited worldwide in field and vegetable crops. In eggplant, alloplasmic CMS lines were developed through interspecific hybridization between Solanum aethiopicum L.?×?S. melongena L., while the restorer (R) lines were isolated from the reciprocal cross. The knowledge about inheritance of Rf gene is must for its further use in breeding and molecular studies. Therefore, four sets of CMS (D-CMS 291A, D-CMS 99A, D-CMS 5A and D-CMS 72A) and restorer (R 2-1, R 3-4, R 6-2 and R 2596-2) lines were used to develop F1, F2 and backcross progenies, to understand the inheritance mechanism. Phenotyping of all the populations and test of goodness of fit revealed involvement of a single dominant gene (Rf) for fertility restoration. The visual scoring of flowers for male sterility and fertility was further validated with the tests on pollen stainability, germination and index. Among others, media containing 0.5% agar?+?300 ppm calcium nitrate?+?5% sucrose?+?50 mg/l boric acid?+?400 mg/l PEG 4000 furnished the best results for in vitro pollen germination. Differences between and within male sterile and restorer lines were observed for pistil and stamen length and girth, pollen stainability and germination. Stable expression of CGMS and restorer lines in all the generation progenies confirmed their utility in future eggplant breeding programs.

  相似文献   
53.
A feeding experiment was conducted for 135 days to observe the effect of different isonitrogenous (35% crude protein) and isocaloric (385 kcal) diets on the growth and carcass composition of giant freshwater prawn, Macrobrachium rosenbergii ( De Man 1879 ). Three experimental diets (ED1, ED2 and ED3) were prepared using locally available ingredients. These diets differed mainly in terms of percent contribution of major protein sources such as fish meal, soybean meal, groundnut oil cake and mustard oil cake. Experimental diets were evaluated against a commercial diet, which served as the control (CD). Juveniles 1.87–2.44 g in size were stocked at a population density of 40 000 ha−1 and fed thrice daily at 10% in the beginning and reducing gradually to 7% and 5% of the body weight during the experimental period. No significant differences (P>0.05) in the growth performance were observed; however, a significantly (P<0.05) higher yield (721.9 kg ha−1 135 days−1) was recorded for prawn fed with control diet, followed by experimental diet 2 (676.5 kg ha−1 135 days−1, having soybean meal as a major protein source). The survival ranged between 63.8% and 77.7%, with different diets showing significantly higher survival. The apparent feed conversion ratio values of diets ranged between 3.15 and 3.49, with experimental and control diets showing non‐significantly lower AFCR values. At the end of the experiment, representative specimens from each treatment were collected and their carcass composition was measured. Analysis of variance showed that carcass protein and total carbohydrate contents were significantly (P<0.05) higher in prawns fed on a fish–soybean meal‐based diet (ED3) and a control diet. The total lipid contents of prawns, however, did not differ significantly among the various dietary treatments. The results of our study suggest that the experimental diets could be used effectively for M. rosenbergii without compromising growth and flesh quality.  相似文献   
54.
55.
This study describes the identification of a quantitative trait locus (QTL) in the recombinant inbred line population of ILL2024 × ILL6788 and subsequent validation of associated molecular markers. A high‐quality genetic linkage map was constructed with 758 markers that cover 1,057 cM, with an average intermarker distance of 2 cM. QTL analysis revealed a single genomic region on Lc2 to be associated with B tolerance and accounted for up to 76% of phenotypic variation (Vp). The best markers for B tolerance were assessed for their utility in routine breeding applications using validation panels of diverse lentil germplasm and breeding material derived from ILL2024. A marker generated from the dense genetic map of this study was found to be the most accurate of all markers available for B tolerance in lentil, with a success rate of 93% within a large breeding pool derived from ILL2024. However, given the number of the unrelated lines for which the marker–trait association was not conserved, B tolerance screening is still required at later stages to confirm predicted phenotypes.  相似文献   
56.
The effect of different levels of nitrogen N0(0kg/ha), N1(30 kg/ha), N2 (60 kg/ha), and N3 (90 kg/ha) and farmyard manure F0 (0 tonnes/ha), F1 (10 tonnes/ha), and F2 (20 tonnes/ha) on the yield and nutrient composition of spinach and its uptake was investigated on a sandy loam soil. Yield; phosphorus, iron, manganese, zinc, and copper uptakes; and ascorbic acid content increased with the application of both the inorganic nitrogen fertilizer and the farmyard manure, with a maximum at the N3F2 level, i.e. at 90 kg N/ha with 20 tonnes FYM/ha. However, the contents of protein, -carotene, and reducing sugars were maximum at the highest dose of nitrogen without the application of farmyard manure.  相似文献   
57.
Different stages of an Indian major carp, Cirrhina mrigala (Hamilton), i.e. hatchling, fry and fingerling, were fed diets supplemented with 3,5,3′-triiodothyronine (T3) at doses of 0, 1, 5 and 10 mg kg?1 diet for 60 days, and then reared on a hormone-free diet for 120 days to study the growth performance of fish during the treatment period (TP) and post-treatment period (PTP). Oral administration of T3 at all the stages resulted in a significantly higher specific growth rate (SGR) and better food conversion ratio (FCR) in comparison to the control group (P<0.05). However, the growth response of C. mrigala towards T3 administration appeared to be stage-specific. At the end of the experimental period of 180days (60days TP+120days PTP), the optimum dosage of T3 appeared to be 5.0 mg kg?1 diet for both hatchlings and fry, and 1.0 mg kg?1 diet for fingerlings, resulting in 62.08%, 30.22% and 13.33% higher weights than in the control group, respectively. The cost of hormone for production of 1 kg of fish was lowest in the case of hatchlings (Rs 0.54), followed by fry (Rs 7.00) and fingerlings (Rs 16.07). Hence, based on the degree of growth response of the fish towards T3 administration in addition to its economics, only incorporation of T3 in the diet of hatchlings appeared to be economical.  相似文献   
58.
The potential of brewer's spent grain (BSG), a common waste from the brewing industry, as a support-substrate for laccase production by the well-known laccase producer Trametes versicolor ATCC 20869 under solid-state fermentation conditions was assessed. An attempt was made to improve the laccase production by T. versicolor through supplementing the cultures with inducers, such as 2,2-azino bis(3-ethylbenzthiazoline-6-sulfonic acid), copper sulfate, ethanol, gallic acid, veratryl alcohol, and phenol. A higher laccase activity of 13506.2 ± 138.2 IU/gds (gram dry substrate) was obtained with a phenol concentration of 10 mg/kg substrate in a tray bioreactor after 12 days of incubation time. The flocculation properties of the laccase treated crude beer samples have been studied by using various parameters, such as viscosity, turbidity, ζ potential, total polyphenols, and total protein content. The present results indicated that laccase (25 IU/L) showed promising results as a good flocculating agent. The laccase treatment showed better flocculation capacity compared to the industrial flocculation process using stabifix as a flocculant. The laccase treatments (25 IU/L) at 4 ± 1 °C and room temperature have shown almost similar flocculation properties without much variability. The study demonstrated the potential of in-house produced laccase using brewer's spent grain for the clarification and flocculation of crude beer as a sustainable alternative to traditional flocculants, such as stabifix and bentonite.  相似文献   
59.
Soils receiving organic manures with and without chemical fertilizers for the last 7 yr with pearlmillet–wheat cropping sequence were compared for soil chemical and biological properties. The application of farmyard manure, poultry manure, and sugarcane filter cake alone or in combination with chemical fertilizers improved the soil organic C, total N, P, and K status. The increase in soil microbial‐biomass C and N was observed in soils receiving organic manures only or with the combined application of organic manures and chemical fertilizers compared to soils receiving chemical fertilizers only. Basal and glucose‐induced respiration, potentially mineralizable N, and arginine ammonification were higher in soils amended with organic manures with or without chemical fertilizers, indicating that more active microflora is associated with organic and integrated system using organic manures and chemical fertilizers together which is important for nutrient cycling.  相似文献   
60.
Micronutrients when fed around peripartum may reduce the stress induced by cortisol. With this objective, 24 Sahiwal (SW) and 24 Karan Fries (KF) cows and 24 Murrah (Mu) buffaloes were taken and divided into four groups of six each. Vitamin E (VE), zinc (Zn) and copper were supplemented from 30 days pre- to 30 days postcalving in groups 1, 2 and 3. Animals without supplementation served as control. Blood sampling was done on days 30, 15, 7 and 3 precalving; at calving; and on days 3, 7, 15 and 30 postcalving. Plasma cortisol levels were measured by ELISA. Supplementation of VE and Zn significantly (P?<?0.05) reduced plasma cortisol levels at calving and at 30 days postcalving. KF cows exhibited best results with VE, whereas SW cows and Mu buffaloes responded best to Zn. Copper increased the peripartum cortisol levels. Reduction in cortisol levels may help in keeping the animal healthy and stronger to fight immuno-suppression generally observed around the period of peripartum.  相似文献   
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