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101.
The persistence patterns of three synthetic pyrethroids—fenvalerate, tau-fluvalinate, lambda-cyhalothrin—and an organophosphorus insecticide, monocrotophos, on eggplant (Solanum melongena L.) have been evaluated. The extractable residues ranged from 0.05 to 0.45, 0.01 to 0.40, 0.003 to 0.09 and 0.09 to 0.32 μg g?1 for fenvalerate, tau-fluvalinate, lambda-cyhalothrin and monocrotophos, respectively. Fenvalerate was the most persistent among the four, followed by monocrotophos, lambda-cyhalothrin and tau-fluvalinate. The Maximum Residue Limit (MRL) of these pesticides on S. melongena has not yet been documented. The present data may be useful for establishing MRL and assessing the amount of pesticide residues in this vegetable.  相似文献   
102.
The survival of vegetative and sporulated cells of the Bacillus cultures on the seeds of the crop plants was tried in different combinations. One milliliter inoculum with 1 mL adhesive combination or sterile water showed better results followed by 1.5 mL inoculum with 0.5 mL adhesive or sterile water. The population of 5.5x10(5) cfu seed(-1) on black gram, 10.5x10(5) cfu seed(-1) on soybean and 6.5x10(5) cfu seed(-1) on maize were observed after 12 h of incubation in 1 mL sporulated inoculum mixed with 1 mL of rice gruel. The sporulated inoculum along with rice gruel favoured the adherence of the regenerated cells as rice gruel is rich in nutrient content.  相似文献   
103.
The substance secreted by mussels, also known as nature’s glue, is a type of liquid protein that hardens rapidly into a solid water-resistant adhesive material. While in seawater or saline conditions, mussels can adhere to all types of surfaces, sustaining its bonds via mussel adhesive proteins (MAPs), a group of proteins containing 3,4-dihydroxyphenylalanine (DOPA) and catecholic amino acid. Several aspects of this adhesion process have inspired the development of various types of synthetic materials for biomedical applications. Further, there is an urgent need to utilize biologically inspired strategies to develop new biocompatible materials for medical applications. Consequently, many researchers have recently reported bio-inspired techniques and materials that show results similar to or better than those shown by MAPs for a range of medical applications. However, the susceptibility to oxidation of 3,4-dihydroxyphenylalanine poses major challenges with regard to the practical translation of mussel adhesion. In this review, various strategies are discussed to provide an option for DOPA/metal ion chelation and to compensate for the limitations imposed by facile 3,4-dihydroxyphenylalanine autoxidation. We discuss the anti-proliferative, anti-inflammatory, anti-microbial activity, and adhesive behaviors of mussel bio-products and mussel-inspired materials (MIMs) that make them attractive for synthetic adaptation. The development of biologically inspired adhesive interfaces, bioactive mussel products, MIMs, and arising areas of research leading to biomedical applications are considered in this review.  相似文献   
104.
Summary General combining ability and its repeatability in the early generations of a potato breeding programme was studied by evaluating 72 progenies (18×4) of 22 parents in a factorial mating design for three successive generations. The mean squares for combining ability due to females, males and females × males were significant for eight out of the ten characters studied. Variance estimates due to specific combining ability were more important than those due to general combining ability for most of the characters in all the generations. General combining ability effects varied from generation to generation. Most of the correlation coefficients between generations for general combining ability effects were significant, but of moderate magnitude (0.5–0.8). Parents with consistent performance over generations and those specifically suitable for a TPS crop were identified.  相似文献   
105.
The efficacy of mannitol versus sorbitol for in vitro conservation of potato microplants at low (7 ± 1 °C) temperature was studied. Two concentrations of sucrose (20 and 40 g l−1) in combination with two concentrations (20 and 40 g l−1) of either mannitol or sorbitol in Murashige and Skoog (MS) medium were tested. Microplant survival, microplant condition, and root growth in three potato genotypes belonging to different maturity groups were studied up to 18 months of in vitro storage without sub-culturing. Best results were achieved with MS medium having 20 g l−1 sucrose plus 40 g l−1 sorbitol. After 18 months without sub-culturing, maximum survival (58.0%) coupled with a microplant condition good enough to provide suitable nodes for sub-culturing was observed with the use of this medium. The results showed that the in vitro storage period could be prolonged by reducing the root growth. The success of conservation was unaffected by the maturity group of the genotypes.  相似文献   
106.
Once renowned as India’s “garden city”, the fast growing southern Indian city of Bangalore is rapidly losing tree cover in public spaces including on roads. This study aims to study the distribution of street trees in Bangalore, to assess differences in tree density, size and species composition across roads of different widths, and to investigate changes in planting practices over time. A spatially stratified approach was used for sampling with 152 transects of 200 m length distributed across wide roads (with a width of 24 m or greater), medium sized roads (12–24 m) and narrow roads (less than 12 m). We find the density of street trees in Bangalore to be lower than many other Asian cities. Species diversity is high, with the most dominant species accounting for less than 10% of the overall population. Narrow roads, usually in congested residential neighborhoods, have fewer trees, smaller sized tree species, and a lower species diversity compared to wide roads. Since wide roads are being felled of trees across the city for road widening, this implies that Bangalore’s street tree population is being selectively denuded of its largest trees. Older trees have a more diverse distribution with several large sized species, while young trees come from a less diverse species set, largely dominated by small statured species with narrow canopies, which have a lower capacity to absorb atmospheric pollutants, mitigate urban heat island effects, stabilize soil, prevent ground water runoff, and sequester carbon. This has serious implications for the city’s environmental and ecological health. These results highlight the need to protect large street trees on wide roads from tree felling, and to select an appropriate and diverse mix of large and small sized tree species for new planting.  相似文献   
107.
在孟加拉西部的Pundibari地区,研究在4个采集(豆荚)时间,3个采集豆荚长度(〈10cm,10-20cm和〉20cm),以及进行的13种预处理对大叶合欢种苗生长和萌发率的影响。豆荚采集时间为2月19日,且没有任何预处理,大叶合欢种子萌发率为92.5%。这明确表明,在2月19日采集的种子具有非休眠,有活力和生理成熟的特性。从长度为10-20 cm豆荚剥离出的种子,2月19日播种,种苗生长良好。利用硫脲预处理种子后,种子的萌发率并没有表现出明显提高,但是当利用低浓度硫脲(100 μL·L-1)预处理种子后,有利于种苗生长。  相似文献   
108.
There has been a highly detrimental impact of the white spot syndrome virus (WSSV) on black tiger shrimp (Penaeus monodon) aquaculture in India. Currently, no cost‐effective measures are available for controlling the disease. One alternative is to improve WSSV resistance through a selective breeding programme for disease‐resistant shrimp, provided that genetic variation exists for this trait. The aim of this study was to evaluate the evidence for genetic variation in resistance to WSSV in P. monodon sourced from Indian populations. Post‐larval shrimp (n=1950) from 54 full‐sibling families were challenged with WSSV using WSSV‐infected mince meat. The heritability was estimated using four different statistical models fitted to the resulting time to death data, including two linear models and two Weibull proportional hazard frailty models. None of the estimated heritabilities were significantly different from zero. We suggest three possible explanations for these results: there actually is very little variation between P. monodon in WSSV resistance and all individuals are highly susceptible to the disease; there is genetic variation in resistance to WSSV in P. monodon but we did not find it in our experiment because the level of challenge in the experiment was too high to allow genetic differences to be expressed; the variation is due to mutations conferring resistance, which are at a low frequency in the population, and we did not sample a broad enough genetic base to capture these mutations.  相似文献   
109.
110.
J. Gopal 《Potato Research》1998,41(4):311-317
Summary In an epiphytotic year of early blight, data were recorded on its incidence in 72 progenies (18 females x 4 males) and their parents planted in a randomised complete block design at the Punjab Agricultural University, Ludhiana, India. Combining ability analysis showed that both additive and non-additive gene action were important, with a preponderance of the latter in the inheritance of resistance to early blight. In general, progenies were as good as or better than mid-parent values. Crosses involving both or at least one parent with good general combining ability resulted in heterotic early blight resistant progenies. Promising parents and crosses were identified.  相似文献   
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