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91.
Fatty fish have been recognized as potential raw material for production of minced meat; however, they are prone to oxidation and further deterioration. In the present study, the effect of washing and antioxidant (tannic acid) treatment on the quality of minced meat of Trachurus trachurus (horse mackerel) during frozen storage was observed. Minced meat of Trachurus trachurus was divided into three lots (T0, T1, and T2). T1 was washed with cold water, T2 with cold water containing tannic acid (100 mg/kg), and T0 was not washed. All the lots were frozen at ?40°C and stored at ?20 ± 2°C for 125 days and were subjected to biochemical, microbiological, and sensory evaluation at regular intervals of 25 days. The antioxidant treatment with tannic acid at the dosage used was found effective in minimizing the rancidity problems of minced meat (T2), compared to T0 and T1. During the whole period of storage, samples from T2 showed good quality in terms of microbiological, biochemical, and sensory analysis compared to T1 and T0.  相似文献   
92.
A diverse array of wild and weedy crucifers was screened under laboratory conditions for their resistance to Lipaphis erysimi (Kaltenbach) (Homoptera: Aphididae). Among these, Brassica fruticulosa and Brassica montana were found to be the most promising. The availability of a synthetic amphiploid, AD-4(B. fruticulosa × Brassica rapa var. brown sarson) as well as a set of Brassica juncea lines carrying genomic introgressions from B. fruticulosa allowed us to investigate B. fruticulosa resistance in greater detail. This assessment was carried out along with susceptible check B. rapa ssp. brown sarson cv. BSH-1 in a series of choice and no choice experiments. The mustard aphid showed maximum preference for feeding on BSH-1 while least preference was recorded for B. fruticulosa followed by AD-4 as evidenced by the number of aphids that settled on circular leaf bits of these genotypes 24 and 48 h after release in a choice experiment. Brassica fruticulosa exhibited strong antibiosis against mustard aphid in no choice experiment and all the released aphids died within 5–8 days of their release, while the maximum survival (76.7%) was recorded on BSH-1. The survival on AD-4 (40%) was significantly lower than that on BSH-1. Almost similar trend was observed with respect to other demographic parameters of L. erysimi viz. development time, fecundity and longevity. In the screen house studies, there was no seedling mortality in B. fruticulosa and AD-4 after 30 days of aphid release while 80% mortality was observed on BSH-1. Excellent variation for aphid resistance was recorded in B. juncea introgression lines, emphasizing heritable nature of fruticulosa resistance. The biochemical analysis suggested the possibility of high concentration of lectins to be associated with low aphid infestation in B. fruticulosa.  相似文献   
93.
The seasonal and annual variability of sensible heat flux (H), latent heat flux (LE), evapotranspiration (ET), crop coefficient (Kc) and crop water productivity (WPET) were investigated under two different rice environments, flooded and aerobic soil conditions, using the eddy covariance (EC) technique during 2008-2009 cropping periods. Since we had only one EC system for monitoring two rice environments, we had to move the system from one location to the other every week. In total, we had to gap-fill an average of 50-60% of the missing weekly data as well as those values rejected by the quality control tests in each rice field in all four cropping seasons. Although the EC method provides a direct measurement of LE, which is the energy used for ET, we needed to correct the values of H and LE to close the energy balance using the Bowen ratio closure method before we used LE to estimate ET. On average, the energy balance closure before correction was 0.72 ± 0.06 and it increased to 0.99 ± 0.01 after correction. The G in both flooded and aerobic fields was very low. Likewise, the energy involved in miscellaneous processes such as photosynthesis, respiration and heat storage in the rice canopy was not taken into consideration.Average for four cropping seasons, flooded rice fields had 19% more LE than aerobic fields whereas aerobic rice fields had 45% more H than flooded fields. This resulted in a lower Bowen ratio in flooded fields (0.14 ± 0.03) than in aerobic fields (0.24 ± 0.01). For our study sites, evapotranspiration was primarily controlled by net radiation. The aerobic rice fields had lower growing season ET rates (3.81 ± 0.21 mm d−1) than the flooded rice fields (4.29 ± 0.23 mm d−1), most probably due to the absence of ponded water and lower leaf area index of aerobic rice. Likewise, the crop coefficient, Kc, of aerobic rice was significantly lower than that of flooded rice. For aerobic rice, Kc values were 0.95 ± 0.01 for the vegetative stage, 1.00 ± 0.01 for the reproductive stage, 0.97 ± 0.04 for the ripening stage and 0.88 ± 0.03 for the fallow period, whereas, for flooded rice, Kc values were 1.04 ± 0.04 for the vegetative stage, 1.11 ± 0.05 for the reproductive stage, 1.04 ± 0.05 for the ripening stage and 0.93 ± 0.06 for the fallow period. The average annual ET was 1301 mm for aerobic rice and 1440 mm for flooded rice. This corresponds to about 11% lower total evapotranspiration in aerobic fields than in flooded fields. However, the crop water productivity (WPET) of aerobic rice (0.42 ± 0.03 g grain kg−1 water) was significantly lower than that of flooded rice (1.26 ± 0.26 g grain kg−1 water) because the grain yields of aerobic rice were very low since they were subjected to water stress.The results of this investigation showed significant differences in energy balance and evapotranspiration between flooded and aerobic rice ecosystems. Aerobic rice is one of the promising water-saving technologies being developed to lower the water requirements of the rice crop to address the issues of water scarcity. This information should be taken into consideration in evaluating alternative water-saving technologies for environmentally sustainable rice production systems.  相似文献   
94.
Chemical hybridizing agents (CHAs) can facilitate two-line breeding in heterosis programs of crops. Twenty-seven oxanilates having different aromatic substitutions were synthesized and screened as CHAs on two genotypes of wheat, PBW 343 and HD 2733, during two Rabi (winter) seasons, 2000-01 and 2001-02. The oxanilates prepared by thermal condensation of anilines with diethyl oxalate or by acylation with ethoxycarbonyl methanoyl chloride were sprayed at 1000 and 1500 ppm at the premeiotic stage of wheat, when the length of the emerging spike of the first node was 7-8 mm. Pollen sterility and spikelet sterility were measured in each treatment. Ethyl oxanilates 5, 6, and 25,containing 4-F, 4-Br, and 4-CF(3) aromatic substituents, respectively, induced greater than 98% spikelet sterility, the desired level, at 1500 ppm. Quantitative structure-activity relationship analysis revealed a direct relationship between F(p) and molecular mass but an inverse relationship between MR, E(S), and R in influencing the bioactivity. Several F(1) hybrids were developed using 5, and at least one showed heterosis.  相似文献   
95.
Genetic Resources and Crop Evolution - The wild Malus germplasm is considered as a gene reservoir for various biotic and abiotic stresses tolerance/resistance genes, including important novel...  相似文献   
96.
High nitrogen fixing, phosphate solubilizing, phytohormones producing isolates of Azotobacter, Azospirillum, Acetobacter and Pseudomonas were used as inoculants for cotton. Important cultures were selected on the basis of their effect on root/shoot length and chemotactic behaviour. Selected bioinoculants were earlier tested for their beneficial properties like nitrogen fixation (ARA), ammonia excretion, IAA production etc. These bio-inoculants were further tested for phosphate solubilization property. Various chosen strains were tested with Desi (HD 123) and American (H 1098) cotton under field conditions (as for wheat). Plant height and boll weight were determined at the time of harvesting whereas survival rate of inoculated bacteria was determined after 30, 80 and 130 days respectively. In the year 2000–01, on the basis of boll number and boll weight plant?1 AVK 51 (36; 76.2?g plant?1), HT 57 (27; 56.9?g plant?1), AC18 (33; 61.5?g plant?1), Ala 27 (36; 61.4?g plant?1) and Pseudomonas (34; 71.3?g plant?1) were identified as significant both for American and desi cotton varieties. Highest survival rate was observed with Mac 68 (33.4 × 105) followed by HT54 (31.5 × 105) after 30 days of sowing, which decreased after 80 days and remained constant up to 130 days. This trend was observed with all the cultures. Similar results were observed in 2001–02. 25?kg ha?1 N saving was observed with A. chroococcum (AVK51) bioinoculant for cotton crop.  相似文献   
97.
We studied leaf litter fall, decomposition and nutrient release patterns of Shorea robusta and Tectona grandis by using a litter bag technique to better understand the release pattern of nutrients to soil from leaf litter. Annual litterfall varied from 13.40 ± 2.56 t ha?1 a?1 for S. robusta to 11.03 ± 3.72 t ha?1 a?1 for T. grandis and the decay constant (k) of decomposed leaf litter was distinctly higher for T. grandis (2.70 ± 0.50 a?1) compared to S. robusta (2.41 ± 0.30 a?1). Biomass loss was positively correlated with the initial litter C, WSC, C/N and ash content in S. robusta and N, P and K concentration for T. grandis. Biomass was negatively correlated with lignin and L/N ratio for S. robusta and L, WSC, L/N and C/N ratio for T. grandis (P < 0.01). Nutrient use efficiency (NUE) and nutrient accumulation index (NAI) of S. robusta was higher than for T. grandis. The retranslocation of bioelements from senescent leaves ranked as P > N > K. Annual N, P and K input to soil through litterfall differed significantly between the two species in the following order: N>K>P. S. robusta was superior in terms of K and P return and T. grandis was superior in terms of N return. The two tree species showed a similar patterns of nutrient release (K > P > N) during decomposition of their leaf litter. Nutrients of N, K and P were the primary limiting nutrients returned to soil through litterfall with important roles in soil fertility and forest productivity.  相似文献   
98.
Rangelands occupy 51% of the terrestrial land surface, 23% total land of Nepal. It contains about 36% of the world's total carbon in above and belowground biomass. Rangelands can aid in the mitigation of rising atmospheric carbon dioxide concentrations via carbon storage in biomass and soil organic matter. A study on carbon stock on soil and vegetation at various altitudinal gradients in Milke-Jaljale rangeland area of Eastern Nepal was made. The study was carried out at three altitudinal gradients (above sea levels) Milke (3,000 m), Gorujure (3,500 m) and Jaljale (4,000 m). This method required establishing a transect line. Sample points were located by pacing the appropriate distances from the point of origin at a transect line. To determine distribution and quantity of plant carbon and soil organic carbon (SOC), 45 sample points were established and 15 points were sampled from each study site. Total soil carbon was estimated as follows: 17.65 t/ha at Milke, 17.27 t/ha at Gorujure and 28.33 t/ha at Jaljale. Similarly, total vegetation carbon was estimated 22.68 t/ha at Milke, 29.79 t/ha at Gorujure and 42.54 t/ha at Jaljale. Highest elevation study site with least external disturbance (Jaljale area) had high storage of carbon in both cases vegetation and soil.  相似文献   
99.
100.
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   
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