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61.
The methanol extract of the whole plant parts of Polygonum viscosum has yielded a flavonol glycoside, 3-O-(6"-caffeoyl)-beta-D-galactopyranoside (1), the structure of which has been determined unambiguously by UV and a series of one- and two-dimensional NMR experiments, notably, (1)H, (13)C, DEPT, COSY45, HMBC and HMQC. 相似文献
62.
Genetic basis of adult plant leaf rust resistance in three released Indian wheat cultivars viz. DWR195, RAJ3765 and HP1731
was investigated through detailed inheritance study under controlled polythene house condition at Flowerdale, India. The F2, F3, F4 and F5 generations were analyzed with the most frequent and virulent Indian leaf rust pathotype 121R63-1. Two complementary recessive
genes imparted resistance in DWR195, two complementary dominant genes governed the resistance of RAJ3765 whereas two independent
dominant genes were involved in the resistance of HP1731. The genes responsible for adult plant resistance in the three cultivars
were not allelic. The two complementary genes of DWR195 and two independent dominant genes of HP1731 have been isolated as
single gene lines. Utilization of resistance from HP1731, which carries two independent dominant genes, will be easy as compared
to DWR195 and RAJ3765. 相似文献
63.
The extracted dye from brown dry rind of the pomegranate has been used as natural colorant for textiles from ancient times. In this study, microwave assisted extraction (MAE) has been used for extraction for dye from dried pomegranate rind. The effect of three independent parameters namely extraction time (25–90 s), pH of solution (3.5–8) and amount of pomegranate rind (0.5–1.5 g) was considered. Response surface methodology (RSM) is applied to optimize the effects of processing parameters of extraction on the yield of dye and a computer-stimulated artificial neural network (ANN) model is developed to get a good correlation between the input variables responsible for extraction and the output parameter (concentration of dye) of extraction from pomegranate rind. Considering the yield of dye extraction and the feasibility of the experiment, the optimum conditions of dye extraction are extraction time 90 s, pH 3.5, amount of sample 1.48. Application of microwave irradiation method proved to be a rapid and improved technique for dye extraction and significantly reduced the extraction time. The optimization procedure shows a close interaction between the experimental and simulated values for dye extraction. 相似文献
64.
Beasley MR Datta S Kogelnik H Kroemer H Monroe D 《Science (New York, N.Y.)》2002,298(5598):1554; author reply 1554
65.
66.
Santiago M. Ulloa Avishek Datta Goran Malidza Robert Leskovsek Stevan Z. Knezevic 《Field Crops Research》2010
Farmers are interested to produce sweet maize under organic production systems and propane flaming could be a potential alternative tool for weed control in organic sweet maize production. Therefore, the objective of this study was to investigate the response of sweet maize to broadcast flaming as influenced by propane dose and crop growth stage. Field experiments were conducted at the Haskell Agricultural Laboratory of the University of Nebraska, Concord, NE in 2008 and 2009 using five propane doses applied at three different growth stages of V2 (2-leaf), V5 (5-leaf) and V7 (7-leaf). The propane doses were 0, 13, 24, 44 and 85 kg ha−1. The response of sweet maize to propane flaming was evaluated in terms of visual crop injury, effects on plant height, yield components (plants m−2, tillers plant−1, number of ears plant−1, cob length and number of seeds cob−1) and fresh marketable yield. The response of different growth stages of sweet maize to propane doses was described by log-logistic models. Based on most parameters tested, V7 was the most tolerant while V2 was the least tolerant stage for broadcast flaming. The maximum yield reductions with the highest propane dose of 85 kg ha−1 were 22%, 12% and 6% for V2, V5 and V7 stages, respectively. Furthermore, a 5% yield reduction was evident with 23, 25 and 36 kg ha−1 of propane for V2, V5 and V7 growth stages, respectively, suggesting that plants flamed at V7 stage can tolerate higher dose of propane for the same yield reduction compared to the other growth stages. We believe that flaming has a potential to be used effectively in organic sweet maize production if properly used. 相似文献
67.
In a lateritic sandy clay loam soil contained in a soil bin, three aggregate size ranges (0.25–0.50, 1.0–2.0 and 2.0–4.0 mm) were established by different tillage intensity to vary the seed—soil contact and to determine the best seedbed for peanut seedling emergence. The general objective was to study the water uptake and diffusivity of the seeds as well as the aeration, water transmission and thermal properties of the seedbed. In the seedbed with the finest aggregate size, the water uptake was maximum and the time needed for germination was least. 相似文献
68.
碳铵粒肥深施是提高氮素回收率,增加水稻等多种作物产量的合理施肥方法之一[1-4,11].国际稻田肥力和肥料评价纲(INSFFER)在南亚、东南亚等十余个稻产国家的试验表明尿素粒肥深施是增产增收的经济施肥法[12]. 相似文献
69.
A. Datta B. M. Sindel P. Kristiansen R. S. Jessop & W. L. Felton 《Journal of Agronomy and Crop Science》2009,195(3):178-185
Isoxaflutole at 75 g ai ha?1 is registered in Australia for the control of several broadleaf weeds in chickpea (Cicer arietinum L.). Although isoxaflutole provides satisfactory control of problematic weeds, under certain conditions crop injury can occur. Higher air temperature and moisture content of soil are reported to affect the metabolism of soil applied herbicide. Controlled environment experiments were used to determine the tolerance of chickpea to isoxaflutole under a range of temperature and soil moisture levels. For the soil moisture study, the variables examined were two desi chickpea genotypes (Kyabra as a tolerant cultivar and Yorker as a sensitive cultivar), three soil moisture levels [50 % field capacity (FC), 75 % FC and FC] with three herbicide rates [0, 75 (recommended rate) and 300 g ai ha?1]. For the temperature by soil moisture study, the variables examined were two other desi chickpea genotypes (97039‐1275 as a tolerant line and 91025‐3021 as a sensitive line), three temperature regimes (20/5, 30/15 and 35/25 °C), two soil moisture conditions (50 % FC and FC) with the same three herbicide rates. The results demonstrated that the chickpea genotypes exhibited differential tolerance to isoxaflutole, but that differences in response were affected by rate, temperature and soil moisture. Increasing temperature and soil moisture content made the susceptible chickpea genotype more vulnerable to isoxaflutole damage. Injury to the susceptible genotype in terms of increased leaf chlorosis and reduction in shoot height and dry matter production increased as soil moisture increased from 50 % FC to FC and temperature increased from 20/5 to 35/25 °C. Overall damage of the sensitive genotype from increasing rates of isoxaflutole also increased when soil moisture content increased from 50 % FC to FC within the fixed temperature regime of 30/15 °C. The sensitivity of chickpea to isoxaflutole depends on existing temperature and moisture content and the chances of crop damage were enhanced with increasing temperature and moisture levels. 相似文献
70.
Arnab Banerjee Jayanta Kumar Datta Naba Kumar Mondal 《Frontiers of Agriculture in China》2010,4(3):341-351
Field experiments were conducted with mustard (Brassica campestris cv. B9) consecutively for three years (2005, 2006 and 2007) in the Crop Research and Seed Multiplication Farm of Burdwan University, Burdwan, West Bengal, India. In the first year, varietal screening of mustard under recommended dose of chemical fertilizer (100:50:50) were performed with seven mustard varieties during November 2005 to February 2006. In the second year, two experiments were conducted to study the effects of six different combined doses of chemical fertilizer and biofertilizer and six different levels of growth retardant cycocel. In the third year, six different levels of compost along with the best screened dose of growth retardant (CCC-300 ppm) and the best combined dose of biofertilizer and chemical fertilizer (3/4thchemical fertilizer:1/4th biofertilizer) from the previous year were applied to study the effects on agronomic traits and growth attributes of mustard, and the field data were analyzed statistically. The variety B9 recorded a significant higher seed yield along with other yield contributing factors, which was found to be superior to other varieties under old alluvial soil of Burdwan, West Bengal, India, in 2005. In 2006 and 2007, seed yield was found to be the best for CCC-300 ppm treatment and the best combined dose of biofertilizer and chemical fertilizer was found to be 3/4th chemical fertilizer:1/4th biofertilizer. In 2007, the best yield was given by the treatment of 7.5 t·hm?2 compost along with the best dose of growth retardant cycocel and the best combined dose of biofertilizer and chemical fertilizer. 相似文献