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311.
312.
Syed Muhammad Zaka Naeem Abbas Sarfraz Ali Shad Rizwan Mustafa Shah 《Phytoparasitica》2014,42(4):493-501
Emamectin benzoate, a semisynthetic bioinsecticide, has been used frequently for the management of lepidopteran pests of cotton worldwide. To assess the resistance risk and design strategy for resistance management, life history traits were established for emamectin benzoate-resistant, unselected and susceptible S. litura strains based on the laboratory observations. Bioassay results showed that the emamectin benzoate-selected strain developed a resistance ratio of 911-fold compared with that of the susceptible strain. The emamectin-selected strain had a relative fitness of 0.37 and lower prepupal and pupal weights, prolonged larval duration and development time, lower fecundity and hatchability compared with the susceptible strain. Mean population growth rates, such as intrinsic rate of population increase and biotic potential, were lower for the emamectin-selected strain compared with the susceptible strain. Development of resistance can cost considerable fitness for the emamectin-selected strain. The present study provided useful information for determining potential management strategies to overcome development of resistance. 相似文献
313.
B. G. Osborne Z. Kotwal A. B. Blakeney L. O'Brien S. Shah T. Fearn 《Cereal Chemistry》1997,74(4):467-470
Single-kernel characterization system (SKCS) 4100 measurements on wheat were reproducible and stable and gave good correlations with relevant reference data, e.g., kernel weight vs. 1,000 kernel weight, kernel hardness vs. particle size index, and kernel moisture vs. oven moisture. Under field conditions at a receiving station in Coleambally (NSW, Australia), the SKCS 4100 operated faultlessly and the reproducibility of the results was as good as in the laboratory. The measurements were completed within the time taken for the normal testing sequence, and the histograms were shown to provide valuable information about the samples that would not otherwise be available. For example, the distribution of moisture contents of individual kernels provides additional information about the samples' potential storage stability. Data on the uniformity of hardness could be interpreted in terms of the potential of the wheat to provide a consistent milling performance. An imprecise (r2 = 0.44) but potentially useful calibration was obtained for the prediction of flour yield under test milling conditions using SKCS 4100 measurements on wheat. A much stronger correlation (r2 = 0.83) was obtained between SKCS data on wheat and the starch damage contents of flours produced on a pilot mill. Thus, the SKCS 4100 has the potential for early generation screening of wheat lines for flour yield and starch damage. 相似文献
314.
315.
H. Kausar Mohd Razi Ismail Halimi Mohd Saud Radziah Othman S. Habib 《Compost science & utilization》2013,21(3-4):121-133
ABSTRACT The present study was conducted at the Composting Unit, Universiti Putra Malaysia to determine the physico-chemical changes, microbial dynamics, and enzyme activities during microbial composting of rice straw at different pH conditions. Different treatments comprising of composting substrates (A), substrates with microbial consortium (B), substrates, microbial consortium, and acetic acid (C), substrates, microbial consortium, and sodium hydroxide (D) were used to enhance the composting process of rice straw. In inoculated treatments, the temperature increased rapidly to higher than 50°C by day 5 and remained above 40°C up to day 17, while in the control the temperature increased slowly and peaked (46°C) at day 9 and remained above 40°C until day 23. The results showed that biodegradation was at its maximum in microbial-infused treatments within 14–21 days as indicated by profiles of pH, reduction of C/N ratio, lignocellulolytic (lignin peroxidase, endoglucanase, and exoglucanase) enzyme activities, and lignocellulose bioconversion. After day 21, the C/N ratio of microbial-infused treatment without any pH adjustment (B) was reduced to 17.5 from an initial value of 29.2 suggesting that there were no additive effects of pH adjustment during the microbial composting of rice straw. 相似文献
316.
Yuyu Chen Aike Zhu Pao Xue Xiaoxia Wen Yongrun Cao Beifang Wang Yue Zhang Liaqat Shah Shihua Cheng Liyong Cao Yingxin Zhang 《水稻科学》2020,27(5):405-413
Grain size is one of key agronomic traits associated with grain yield and grain quality. Both major quantitative trait loci GS3 and GL3.1 play a predominant role in negative regulation of grain size. In this study, a CRISPR/Cas9-mediated multiplex genome editing system was used to simultaneously edit GS3 and GL3.1 in a typical japonica rice Nipponbare. In T_1 generation, we found that gs3 formed slender grain with lower chalkiness percentage, while gs3gl3.1 produced larger grain with higher chalkiness percentage. In terms of other agronomic traits, flag leaf size, grain number and grain yield of both gs3 and gs3gl3.1 mutants were affected. It is noteworthy that gs3 and gs3gl3.1 mutants both led to dramatical reduction of grain number, thereby decreased grain yield. In conclusion, these results indicated that knockout of GS3 and GL3.1 could rapidly improve grain size, but probably have some negative influences on grain quality and grain yield. 相似文献
317.
Chunxiao Sun Ziping Zhang Zilin Ren Liu Yu Huan Zhou Yaxin Han Mudassir Shah Qian Che Guojian Zhang Dehai Li Tianjiao Zhu 《Marine drugs》2020,18(11)
Three new aspochracin-type cyclic tripeptides, sclerotiotides M–O (1–3), together with three known analogues, sclerotiotide L (4), sclerotiotide F (5), and sclerotiotide B (6), were obtained from the ethyl acetate extract of the fungus Aspergillus insulicola HDN151418, which was isolated from an unidentified Antarctica sponge. Spectroscopic and chemical approaches were used to elucidate their structures. The absolute configuration of the side chain in compound 4 was elucidated for the first time. Compounds 1 and 2 showed broad antimicrobial activity against a panel of pathogenic strains, including Bacillus cereus, Proteus species, Mycobacterium phlei, Bacillus subtilis, Vibrio parahemolyticus, Edwardsiella tarda, MRCNS, and MRSA, with MIC values ranging from 1.56 to 25.0 µM. 相似文献
318.
Soil cadmium (Cd) causes toxicity and oxidative stress, alters biochemical processes and rootknot formation in rice. Irrigation of exogenous peroxidase (POX) together with its co-substrate H2O2(POXRice + H2O2), is likely to have protective effect upon the biochemical and nodular changes in ricegrown in Cd-rich soil. Exposure to Cd concentration of 1.00 mg/L increased oxidative stress, loss of cellviability, electrolyte leakage and root knot formation, whereas it significantly lowered the chlorophyll leveland rhizobium growth in rice. Irrigation of exogenous POXRice + H2O2 to Cd-stressed rice seedlingsreversed the Cd-induced alterations in rice to levels similar in control (non-stressed) seedlings. Resultsprovided strong evidence of exogenous POXRice + H2O2-mediated reversal and restoration of physiologicaland biochemical processes as well as increased resistance of rice seedlings to root knot formation.Irrigation with POXRice + H2O2 appeared to contribute towards bringing normoxic conditions in the otherwisehypoxic soil environment by enhancing the O2 in pot-experiments due to reduced Cd uptake, enhancedmineral homeostasis of essential elements viz. P, Fe, Mo, Mg and Mn for maintenance of root architecturedamaged by lipid peroxidation and reduction in oxidative stress by reducing Cd-induced reactive oxygenspecies generation. Therefore, the mitigation of Cd-toxicity in rice through this novel approach appeared tobe a promising mode to limit Cd-uptake, modulate protective and tolerance mechanisms for sustainablerice yield in Cd-contaminated rice-croplands and prevent nematode attack in rice, however, more detailedstudies are needed prior to large scale applications. 相似文献
319.
Md. Shah Alam Shin-ichi Teshima Manabu Ishikawa Daisuke Hasegawa & Shunsuke Koshio 《Aquaculture Research》2004,35(9):842-849
The requirements for essential amino acids by kuruma shrimp, Marsupenaeus japonicus (Bate) have not yet been determined using the dose–response method due to poor utilization of crystalline amino acids (CAA). In a previous study, we produced coated CAA that could be used to retard leaching losses. Therefore, to determine the arginine requirement of juvenile kuruma shrimp, a growth study was conducted using test diets containing six levels of coated arginine (from 1.20% to 3.19% of diet) for 42 days. Crystalline amino acids was supplemented to correspond to the amino acid pattern in the whole body protein of the kuruma shrimp except for arginine. To reduce leaching losses, CAA were coated with carboxymethylcellulose (CMC) and diets were further bound with CMC and k‐carrageenan. Test diets were fed to triplicate groups of juveniles (0.25±0.02 g) twice a day. Proximate composition and the amino acid composition of shrimp whole bodies were analysed at the end of the feeding trial. Percent body weight gain (WG), specific growth rate, feed intake, feed efficiency ratio and protein retention efficiency were significantly affected by the dietary arginine concentrations. Estimating the arginine requirement of kuruma shrimp using broken‐line analysis of percent WG resulted in a value of 2.66% of diet or 5.32% of protein. After correcting for leaching of arginine from the diets, the optimum dietary value of arginine for kuruma shrimp was a little lower than the estimated value. 相似文献
320.