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111.
用10年生丛生竹的节片通过离体腋笋增殖和生根产生出府竹小苗。不同季节对无菌培养物的建立、腋芽发萌和初代培养的影响很大。3片丛生林中,无菌培养物的建立有差别,但腋芽发萌没有差别。用加有31.06uM BA和2.85um IAA的MS液体介质,最大的增值率为3.18;用加有20~25um IBA MS液体介质,离体生根率为66.7~77.8%。用不同的植物生长素,生根所用的天数也不同,而IBA液能在短期促进生根,仅仅为2-3周。成功炼苗后,在装有土壤、沙子和农家肥塑料袋里,离体繁殖的小苗成活率为90%,大约有2000株小苗用于野外栽植。 相似文献
112.
113.
Y. SinghV.P. Singh G. SinghD.S. Yadav R.K.P. SinhaD.E. Johnson A.M. Mortimer 《Field Crops Research》2011,121(1):64-74
The implications of adopting alternative seeding methods for rice and wheat establishment were examined at three geographically separate sites in the rice-wheat system of the Indo-Gangetic plains, across northern India. Rice yields in cultivated plots, established by either wet or dry seeding methods, were evaluated in comparison to yields from zero-tillage plots and under conventional transplanting methods. In the same trials, the effects of crop establishment methods in wheat were assessed both on wheat yields and rice yields. Rice crop establishment methods markedly influenced the emerging weed flora and attainable yields were measured in relation to intensity of weed management. Over four years, average rice grain yields in the absence of weed competition were greatest (6.56 t ha−1) under wet seeding (sowing pre-germinated rice seed on puddled soil), and similar to those from transplanted rice (6.17 t ha−1) into puddled soil, and dry seeded rice after dry soil tillage (6.15 t ha−1). Lowest yields were observed from dry seeded rice sown without tillage (5.44 t ha−1). Rice yield losses due to uncontrolled weed growth were least in transplanted rice (12%) but otherwise large (c. 85%) where rice had been sown to dry cultivated fields or to puddled soil, rising to 98% in dry seeded rice sown without soil tillage. Weed competition reduced multiple rice yield components, and weed biomass in wet seeded rice was six-fold greater that in rice transplanted into puddled soil and twice as much again in dry seeded rice sown either after dry tillage or without tillage. Wheat grain yields were significantly higher from crops sown into tilled soil (3.89 t ha−1) than those sown without tillage (3.51 t ha−1), and also were elevated (5% on average) where the soil had been dry cultivated in preparation for the previous rice crops rather than puddled. The method of wheat cultivation did not influence rice yield. Soil infiltration rates in the wheat season were least where the land had been puddled for rice (1.52 mm h−1), and greater where the soil had been dry-tilled (2.63 mm h−1) and greatest after zero-tillage (3.54 mm h−1).These studies demonstrated at research managed sites across a wide geographic area, and on farmers’ fields, that yields of dry seeded rice sown after dry cultivation of soil were broadly comparable with those of transplanted rice, providing weed competition was absent. These results support the proposition that direct seeding of rice could provide an alternative to the conventional practice of transplanting, and help address rising costs and threats to sustainability in the rice-wheat rotation. Further, analysis of patterns of long-term rainfall data indicated that farmers reliant on monsoon rainfall could prepare fields for dry direct seeded rice some 30 days before they could prepare fields for either transplanting or seeding with pre-germinated seed. Dry, direct seeding of rice contributes a valuable component of an adaptive strategy to address monsoonal variability that also may advance the time of wheat establishment and yield. Whilst the results illustrate the robustness, feasibility and significant potential of direct seeded rice, they also highlight the critical nature of effective weed control in successful implementation of direct seeding systems for rice. 相似文献
114.
V. Phogat A. K. Yadav R. S. Malik Sanjay Kumar Jim Cox 《Paddy and Water Environment》2010,8(4):333-346
The HYDRUS-ID model was experimentally tested for water balance and salt build up in soil under rice crop irrigated with different
salinity water (ECiw) of 0.4, 2, 4, 6, 8 and 10 dS m−1 in micro-lysimeters filled with sandy loam soil. Differences of means between measured (M) and HYDRUS-1D predicted (P) values of bottom flux (Q
o) and leachate EC as tested by paired t test were not found significant at P = 0.05 and a close agreement between RMSE values showed the applicability of the HYDRUS-1D to simulate percolation and salt
concentration in the micro-lysimeters under rice crop. Potential ET values of rice as obtained from CROPWAT matched well with
model predicted and measured one at all ECiw treatments. The model predicted root water uptake varied from 66.1 to 652.7 mm
and the maximum daily salt concentration in the root zone was 0.46, 2.3, 4.5, 6.7, 8.4 and 10.2 me cm−3 in 0.4, 2, 4, 6, 8 and 10 dS m−1 ECiw treatments, respectively. The grain production per unit evapotranspiration (
\textWP\textET\texta {\text{WP}}_{{{\text{ET}}_{\text{a}} }} ) value of 2.56 in ECiw of 0.4 dS m−1 treatment declined to 1.31 with ECiw of 2 dS m−1. The
\textWP\textET\texta {\text{WP}}_{{{\text{ET}}_{\text{a}} }} reduced to one-fifth when percolation was included in the productivity determination. Similarly, the water productivity in
respect of total dry matter production (TDM) was also reduced in different treatments. Therefore, the model predicted values
of water balance can be effectively utilized to calculate the water productivity of rice crop. 相似文献
115.
Devesh K. Yadav Subhash Taraphder Ajit K. Sahoo K. C. Dhara 《Veterinary research communications》2010,34(3):277-284
The aim of this study was to determine the genetics of polymorph systems of Transferrin in Garole sheep breed. The present
study was conducted on 95 adult Garole sheep comprising 52 ewes and 43 rams, maintained at Sheep and Goat Breeding Farm of
West Bengal University of Animal and Fishery Sciences, West Bengal, during the period from April–September, 2009. The polymorphism
of transferrin was determined through SDS-Polyacrylamide gel electrophoresis technique. It was found that the transferrin
type was controlled by five codominant alleles (TfA, TfB, TfC TfD and TfE) in Garole sheep. These five alleles, because of
co-dominant nature of inheritance, determined the occurrence of nine transferrin genotypes in the analyzed flock. Four (TfAA,
TfBB, TfCC and TfDD) of these were homozygous and the remaining five (TfAD, TfBC, TfBD, TfCD and TfDE) heterozygous. It was
found that the TfDD genotype (0.263) was predominant while TfDE genotype (0.042) was least common in the analyzed flock. Frequencies
of other genotypes were as: TfCD(0.242), TfBD(0.126), TfCC(0.084), TfBB(0.074), TfAA(0.063), TfAD and TfBC (0.053 for each
genotype ) in whole population. From the result it was found that in whole population combined, the heterozygotic genotypic
frequency (0.516) was more than that of homozygotic genotypic frequency (0.484). Considerable variations were recognized in
the frequencies of transferrin alleles. In the whole population frequencies of transferrin alleles were found to be TfA = 0.089,
TfB = 0.163, TfC = 0.232, TfD = 0.495 and TfE = 0.021. Transferrin system has shown an absence of genetic equilibrium among
the analyzed herd (χ2 value = 51.31). In conclusion, there were polymorphism in Transferrin types and the presence of differences
among the frequencies of the five alleles by categories could be a source of genetic variation in Garole sheep. 相似文献
116.
Cassia occidentalis L. is an annual or perennial Ayurvedic plant which is used in several traditional medicines to cure various diseases. This weed has been known to possess antibacterial, antifungal, antidiabetic, anti-inflammatory, anticancerous, antimutagenic and hepatoprotective activity. A wide range of chemical compounds including achrosin, aloe-emodin, emodin, anthraquinones, anthrones, apigenin, aurantiobtusin, campesterol, cassiollin, chryso-obtusin, chrysophanic acid, chrysarobin, chrysophanol, chrysoeriol etc. have been isolated from this plant. The presented review summarizes the information concerning the botany, ethnopharmacologyquery, phytochemistry, biological activity and toxicity of the C.occidentalis plant. 相似文献
117.
J. L. Mangal R. K. Singh A. C. Yadav S. Lal U. C. Pandey 《The Journal of Horticultural Science and Biotechnology》2013,88(6):657-658
Salinity tolerance in garlic cultivars was studied in pots. A 50% yield reduction occurs at 5.60-7.80 dS m1, depending on genotype. It was estimated that if soil salinity exceeds 1.70 dS m_l, the mean garlic yield declined by 1.68% per unit increase in soil salinity. 相似文献
118.
119.
K. Joseph John Sheen Scariah V. A. Muhammed Nissar M. Latha S. Gopalakrishnan S. R. Yadav K. V. Bhat 《Genetic Resources and Crop Evolution》2013,60(3):1037-1046
Recent research point to the Indian wild taxa of Cucumis callosus (Rottler) Cogn. as the wild progenitor of melon (C. melo L.). Overlapping distribution with cultivated and weedy and feral forms of melo and normal fertility of F1 and BC1 generations of its cross with cultivated melon indicate its progenitor status. A perusal of herbarium data indicate its natural distribution pattern in the region comprising Vindhya Hills and Aravalli mountain ranges extending northwards to Indo-Gangetic plains and southwards to the Deccan plateau touching rain shadow areas of Western Ghats. Characterised by drought tolerance and field resistance to a host of pests and diseases, it is conspicuously absent in the high rainfall areas of Western Ghats and upper Himalayan region. Based on its morphological distinction and F1 and BC1 fertility with C. melo, a subspecific rank within C. melo is postulated. First-hand information on its occurrence, distribution and crossability relationship with other Indian taxa of Cucumis are given. 相似文献
120.
Effect of nutrients and plant extracts on Alternaria blight of tomato caused by Alternaria Alternata
Sharma Ratan Lal Ahir R. R. Yadav Shankar Lal Sharma Pinki Ghasolia R. P. 《植物病害和植物保护杂志》2021,128(4):951-960
Journal of Plant Diseases and Protection - Studies with nutrients and phyto-extracts were performed in vitro and in vivo to assess their potential in controlling Alternaria blight of tomato... 相似文献