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91.
Evaluating novel microbe amended composts as biocontrol agents in tomato   总被引:1,自引:0,他引:1  
An investigation was conducted to evaluate the potential of antagonistic cyanobacteria/bacterial cultures amended compost and compost tea preparations for suppressing diseases caused by plant pathogenic fungi Fusarium oxysporum, Pythium debaryanum, Pythium aphanidermatum and Rhizoctonia solani in tomato. Two types of microbe-fortified composts and the compost tea preparations, along with the recommended biological control (Trichoderma formulation) and chemical control (Thiram-Carbendazim), were used for inoculating the potting mixture. Comparative performance of the treatments revealed the superiority of both the composts/compost tea preparations in enhancing seed germination, seedling length and biomass in the fungi challenged treatments. The most effective control of the diseases was obtained by the composts amended with Anabaena oscillarioides C12 and Bacillus subtillis B5 and the compost tea preparations. Both treatments provided significantly better control than the other treatments in terms of reduction in disease severity, reduction of fungal load and enhancement of plant parameters. Our study reveals the efficacy of microbe-fortified composts for use in control of the studied root diseases caused by phytopathogenic fungi.  相似文献   
92.
A mid altitude (700–1200 m amsl.) village in Garhwal Himalaya was analysed in terms of energy and economic efficiency of different land use-land cover types constituting the landscape. Simultaneous agroforestry, sequential agroforestry, home garden and community forests accounted for 27.47%, 27.47%, 1.1% and 43.96% of the total geographical area of the village. Simultaneous agroforestry is the traditional land use involving substantial input of manure derived from forest litter and animal excreta and was practised on terraced slopes in private ownership. Tree cover in this system was represented by nine species with total average density of 390 trees ha−1, Grewia optiva and Boehmeria rugulosa being the most dominant. Sequential agroforestry system involving slash-burn practice and cultivation on unterraced slopes without tillage and manuring was an illicit land use on community lands where forestry land use is desirable as per the government policy. Per ha annual energy input in simultaneous agroforestry system was 305267 MJ compared to 279 MJ in sequential agroforestry and 27047 MJ in home garden. In monetary terms, highest per ha annual output was obtained from simultaneous agroforestry (Rs 25370, Rs 35 = US$1) followed by home garden (Rs 18200) and sequential agroforestry (Rs 9426). Local food, fodder and fuelwood production was in excess of the local consumption. While most of the surplus food was stored, surplus fodder and fuelwood were sold for cash. Production in simultaneous agroforestry system in private lands was sustained with substantial biomass and nutrient inputs from the community and government forests. Land use-land cover changes in the region are driven by the interaction of ecological, policy and human factors. It is concluded that present policy of treating forests and agriculture as closed and independent ecological or production systems needs to be replaced by an integrated land use policy. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
93.
Proteins, inevitable for nutritional security of human beings and legumes, by far, are the cheapest source of this vital nutrient. The escalating prices and never halting population growth limit the per capita availability of protein-rich legumes. In view of limited land resource and need to grow other food crops, the greater protein harvests are possible only by increasing the protein levels of popularly grown legumes. In this context, attempts were made for raising the protein content in pigeonpea [Cajanus cajan (L.) Millsp.] through traditional plant breeding tools. For this, the high-protein trait was successfully transferred from wild relatives of pigeonpea to the cultivated types. In the derived inbred lines, the protein content was significantly enhanced from 20% - 22% to 28% - 30%. Two high-protein lines HPL 40 and HPL 8 also produced 2100 and 1660 kg/ha grain yield, respectively. This simply means that, in comparison with traditional cultivars, the cultivation of high-protein lines will provide additional 100 kg/ha of digestible protein to the farming family. This paper, besides describing the breeding procedures, also discusses the accomplishments of this breeding endeavour with respect to its various nutritional and biological properties.  相似文献   
94.
Five short-duration pigeonpea (Cajanus cajan (L.) Millsp.) genotypes were grown at three plant populations in three locations during the 1986 and 1988 rainy seasons, to determine the physiological basis of observed variations in yield. Significant differences were found in seed yield (Y), crop growth rate (C), and the durations of vegetative (Dv) and reproductive (Dr) growth, and partitioning (P). These were attributable to genotypes and their interactions with environments (except for C). Variation in C, Dr, and P together explained 78 % of the observed variation in Y due to different genotypes and environments. Crop growth rate alone contributed about 71 % of the variation in Y, and reached an optimum value of around 6.5 kg ha?1°Cd?1. Crop growth rates increased with the duration of the vegetative period and with plant population. However, a negative relationship between C and P resulted in plant population having little effect on seed yield. The maximum-yielding genotype, ICPH 8 had the highest C and an intermediate P.  相似文献   
95.
Ochrus chickling ( Lathyrus ochrus (L.) D.C.) is a promising feed legume for rain-fed farming systems in the Mediterranean environments of West Asia and North Africa (WANA) because of its drought tolerance and resistance to broom rape ( Orobanche crenata Forsk.). However, it is highly susceptible to cold and improving Its resistance would further improve its adaptation.
The potential of the chlorophyll fluorescence technique in screening for frost sensitivity in seedlings of five Lathyrus ochrus genotypes and one each of Vicia ervilia (L.) Wild and V. sativa L. was assessed by measuring the rate of rise in induced or variable chlorophyll fluorescence of fully developed leaflets after cold hardening in the open and subsequent exposure to freezing. The method differentiated the highly frost-susceptible L. ochrus genotypes from the more tolerant Vicia species. Testing the technique with nine genotypes of L. ochrus in which the plants were established, cold-hardened and frost-stressed under controlled conditions confirmed its sensitivity even to reveal the narrow inter plant differences that generally exist within a cultivar or genotype to frost. It is therefore considered as a useful screening technique for cold/frost tolerance in L. ochrus.  相似文献   
96.
97.
Several randomly selected glasshouse grown somaclones of rose scented geranium, Pelargonium graveolens L’Her Ex Ait. cv. Hemanti were successfully transferred to the field in Northern India for evaluation. Two distinct morphotypes were described on the basis of leaf dentation-one resembling the parental cultivar in having highly dentated leaves (HDL) and the other with less dentated leaves (LDL). After repeated field-testing for 3 consecutive years, the HDL clones closely resembled the parental cultivar with respect to the different quantity and quality determining traits, while the LDL group was clearly different. The field established LDL somaclones possessed higher herb yield, number of branches and other oil yield attributing traits as compared to the HDL clones and the parent cultivar. The chemical investigations of the essential oil revealed significant differences between the LDL clones, the HDL clones and the control. Selection of such somaclones, which are superior to the parental in most of the quantitative and qualitative traits and show better adaptability to different areas of cultivation, will help towards commercialization of geranium in India.  相似文献   
98.
In this study, inoculation of the chickpea (Cicer arietinum) with the novel symbiotic fungus (Piriformospora indica) was analysed in combination with the Tn5-lacZ-tagged phosphate-solubilising bacterium Pseudomonas striata. This study aims to evaluate whether the co-inoculation of these two species would enhance the population buildup of P. striata in the rhizosphere, P uptake, growth and yield of chickpea. Single inoculation of P. indica and P. striata has a negative effect on plant growth and yield of chickpea. Data showed that the combination of the two microorganisms had a synergistic effect on population buildup of P. striata and plant dry biomass with respect to their single inoculation. However, the P uptake was not significantly influenced by single or combined inoculation of two species. At 20 days after sowing, the influence of combined inoculation on the population of P. striata was positive; at 60 days after sowing, it was neutral as the populations in treatments with single and combined inoculation were at par; and at harvest, it was negative The population of P. striata was higher at flowering stage as compared to 20 days after sowing and at harvest.  相似文献   
99.
Ethanolic extract of Beta vulgaris roots given orally at doses of 1000, 2000 and 4000 mg/kg exhibited significant dose-dependent hepatoprotective activity against carbontetrachloride (CCl(4))-induced hepatotoxicity in rats. Hepatotoxicity and its prevention were assessed by serum markers viz. cholesterol, triglyceride, alanine amino transferase and alkaline phosphatase.  相似文献   
100.
For enhancing productivity and profitability of pigeonpea (Cajanus cajan (L.) Millsp.) a hybrid breeding technology based on a cytoplasmic nuclear male-sterility (CMS) system was developed at International Crops Research Institute for the Semi-Arid Tropics (ICRISAT). Among the elite hybrids ‘ICPH 2671’ was most out-standing with 30–35% yield advantage over local varieties. Despite its commercial release in 2010, this hybrid could not attract many growers due to its less preferred seed color. Both the parents (ICPA 2043 and ICPR 2671) of this hybrid and their crossed seeds had Greyed-orange [code no*: 167B/C (* The standard identification numbers of Royal Horticultural Society)] color. However, the commercial seeds produced on the hybrid plants surprisingly have Greyed-purple (code no: 183C) color that fetches relatively less profits. To understand the genetics of this phenomenon a cross combination was studied for seed color in F1, F2, and B1C1F1 generations. The data suggested that three independent dominant genes controlled the expression of seed coat color. The observations further suggested the presence of two dominant genes (Brsd 1 and Brsd 2 ) in the male-sterile line ‘ICPA 2043’, ‘ICPR 2671’ and another dominant gene (Brsd 3 ) in the restorer line. In the hybrid plants genes Brsd 1 and Brsd 2 act in complementation with the third gene Brsd 3 , this also acts as a modifier. The presence of Brsd 3 gene in a genotype together with Brsd 1 and/or Brsd 2 produces a strong inter-allelic epistatic interactions resulting in the Greyed-purple (183C) seed color. It was further postulated that the genetic constitution of ‘ICPA 2043’ is Brsd 1 Brsd 1 Brsd 2 Brsd 2 brsd 3 brsd 3 , while the genotype of the restorer line ‘ICPR 2671’ is brsd 1 brsd 1 brsd 2 brsd 2 Brsd 3 Brsd 3 .  相似文献   
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