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61.
Summary In pearl millet hairy lamina, hairy sheath and hairy stem were inherited as monofactorial recessives while hairy leaf margin and hairy node were inherited as monogenic dominant traits. The gene for hairy lamina hl showed independent assortment from the gene for hairy node, Hn, and showed linkage with the genes hst (hairy stem), hs (hairy sheath) and Hm (hairy leaf margin). Furthermore, Hl was observed to have an epistatic effect on the expression of hs. The percentages of recombination between the gene pairs hl-hst, hl-hs and hl-Hm were 0.0, 8.30±0.44 and 19.81±0.98 respectively. Thus the genes hl-hst-hs Hm form one linkage group.  相似文献   
62.
McKay  G.  Porter  J. F.  Prasad  G. R. 《Water, air, and soil pollution》1999,114(3-4):423-438
The ability of five low cost adsorbents – rice husk, cotton, bark, hair and coal – to adsorb two basic dyes, namely, Safranine and Methylene Blue, has been studied. Equilibrium isotherms have been determined and analysed using the Langmuir equations. The monolayer saturation capacities for Safranine are 1119, 838, 875, 190 and 120 mg g-1adsorbent and for Methylene Blue are 914, 312, 277, 158 and 250 mg g-1adsorbent for bark, rice husk, cotton waste, hair and coal respectively. A limited number of fixed bed column studies have been performed and the bed depth service time for each dye-adsorbent system has been determined.  相似文献   
63.
A 60 days feeding trial was conducted to illustrate the effect of graded levels of protein on the growth and metabolic enzymes of grey mullet (Mugil cephalus L.) fingerlings reared in inland saline water (ISW). Six isoenergetic (16 MJ/kg) and isolipidic (60 g/kg) diets containing 240, 260, 280, 300, 320 and 340 g crude protein (CP)/kg diet were formulated and fed to triplicate. Weight gain %, specific growth rate, protein utilizing efficiency, feed efficiency and RNA:DNA ratio were significantly higher (p < .05) in 320 and 300 g CP/kg diets. Fish fed with 240 g CP/kg diet showed significantly higher (p < .05) feed intake, whole‐body lipid content, hepatosomatic index value and liver glycogen content. Transaminase enzymes and malate dehydrogenase activities were elevated in fish fed 340 g CP/kg diet. Protease activity increased with increasing dietary CP level, but amylase activities showed an inverse relationship. No significant (p > .05) variations were observed for lactate dehydrogenase, oxidative stress enzymes, blood parameters and serum osmolality among all the treatment groups, but red blood cell count increases with increasing dietary CP levels. Based on the results, feeding dietary protein level of 300 g CP/kg is economically viable for rearing of grey mullet in ISW.  相似文献   
64.
In this experiment, weed management was studied in zero tillage (ZT) and conventional tillage (CT) wheat with and without crop residue and nitrogen (N). The treatment ZT with crop residue retention (R) and 75% of required N plus GreenSeeker? (GS)-aided N management (ZTRNGS) resulted in a reduction of density and dry weight of weeds compared to CT and ZT without residue. Sequential application of pendimethalin and sulfosulfuron (PMT-SSF) reduced the weed density and dry weight compared to the weedy check (WC). Importantly, the richness and diversity indices were high in ZTRNGS and in WC treatments. Greater wheat grain (5.11 t/ha) and biomass yield (13.31 t/ha) were observed in ZTRNGS than CT without residue and blanket split application of N (CTN). The treatment ZTRNGS recorded 14.1% and 16.9% higher gross and net returns, respectively, over CTN. This study demonstrates that surface retention of crop residue in ZT is more useful than residue incorporation under CT for effective weed control, improving crop yield and profitability.  相似文献   
65.
Wheat is an important cereal food crop providing key nutrients to humankind. Rusts are the most destructive pathogens of cereal crops, with the exception of rice, across the world and resistant cultivars have been widely employed to reduce the yield losses caused by them. The modern intensive monoculture of cultivars and changing climatic conditions has created congenial conditions for the emergence of new virulent races such as Ug99, which is a great concern for world food security. Conventional breeding efforts have not been effective in quickly developing new varieties with durable and broad‐spectrum resistance against the rapidly evolving rust pathogen races. However, in the last two decades, biotechnological methods such as marker‐assisted selection (MAS) and transgenic technology have provided novel strategies for enhancing resistance levels and durability in crop plants in a short span of time. Nevertheless, broad application of transgenics in agriculture is hindered by biosafety apprehensions. In recent years, improved versions of biotechnological breeding methods such as genomic selection, genome editing technologies, cisgenesis and intragenesis, RNA‐dependent DNA methylation (RdDM), agroinfiltration and reverse breeding are gaining popularity. These technologies provide a tremendous capability to manipulate crop plants more precisely than before and accelerate crop improvement efforts for sustained food production as well as overcoming safety concerns associated with food crops.  相似文献   
66.
In rice, totally one hundred and three genotypes were evaluated for resistance against blast disease in three hot spot locations of Guyana. The experiments were conducted in spring and autumn seasons of 2015, 2016 and 2017. The modified upland blast nursery (UBN) method was adopted for screening blast resistance. The Additive Main effects and Multiplicative Interaction (AMMI) analysis was applied to understand the interaction between genotype (G) and environment (E). The results of all seasons at three locations showed the consistent expression of high resistance by genotype FL 127 followed by FG12–08 and FG12–273. The AMMI analysis of variance (ANOVA) revealed that, resistance was dominated by the genotype main effect. The magnitude of genotypes by environment (G x E) sum of square (SS) was 3.64 times smaller than genotype SS, and 6.74 times larger than environment SS. The analysis has indicated that the differences of the genotypes across the environment were not substantial. All of the seven environment vectors appeared to be positively correlated. The screening at Onverwagt Back, autumn 2016 (E7) and Black Bush Polder, spring 2015 (E5) were observed to be the most representative environment. This was clearly revealed by smaller average - environment axis (AEA) angle. Likewise, E4 (Canje, autumn 2015) was observed closer to the “ideal test environment”, thus suggested as an ideal environment for blast resistant screening. Also, genotypes clustered near the origin have showed stable blast disease resistant status and contributed little to both G and G x E. These genotypes proposed as useful ones for breeding disease resistant varieties and hybrids in rice.  相似文献   
67.
68.
Cage‐pond integration system is a new model for enhancing productivity of pond aquaculture system. A field trial was conducted using African catfish (Clarias gariepinus) and Nile tilapia (Oreochromis niloticus) in cages and carps in earthen ponds. There were four treatments replicated five times: (1) carps in ponds without cage, (2) tilapia at 30 fish m?3 in cage and carps in open pond, (3) catfish at 100 fish m?3 in cage and carps in open pond, (4) tilapia and catfish at 30 and 100 fish m?3, respectively, in separate cages and carps in open pond. The carps were stocked at 1 fish m?2. The cage occupied about 3% of the pond area. The caged tilapia and catfish were fed and the control ponds were fertilized. Results showed that the combined extrapolated net yield was significantly higher (P < 0.05) in the catfish, tilapia and carps integration system (9.4 ± 1.6 t ha?1 year?1) than in the carp polyculture (3.3 ± 0.7 t ha?1 year?1). The net return from the tilapia and carps (6860 US$ ha?1 year?1) and catfish, tilapia and carps integration systems (6668 US$ ha?1 year?1) was significantly higher than in the carp polyculture (1709 US$ ha?1 year?1) (P < 0.05). This experiment demonstrated that the cage‐pond integration of African catfish and Nile tilapia with carps is the best technology to increase production; whereas integration of tilapia and carp for profitability.  相似文献   
69.
The cotton mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae), an invasive pest species, has appeared on a large scale on cotton in India since 2006. Its distribution within the plant, and associated yield losses in cotton, were studied over 2 years. Distribution of P. solenopsis was observed within the cotton plant from vegetative to boll formation stage. In the vegetative and square formation stages, the highest mealybug population was recorded on the upper portion of the stem, followed by the middle leaves of the plant. In the boll formation stage, there was no significant difference in distribution of the insect among plant parts. Losses in cotton due to the mealybug varied between 14.9% at Grade 1 and 53.6% at Grade 4, on a 0 to 4 severity index, with a mean reduction of 35% and 32%, during 2008 and 2009, respectively. There was a significant relationship between severity of infestation and decrease in seed cotton yield. The information generated from this study will help in the early detection of mealybug infestation and estimation of yield losses corresponding to the severity grade of the damage.  相似文献   
70.
Paratuberculosis or Johne’s disease is a chronic gastric disease of ruminants. For this disease there is no effective treatment or preventive measure available. 16.8 kDa protein is an immunogenic protein of Mycobacterium avium paratuberculosis and can be an ideal candidate for developing a DNA vaccine construct. In present study a bicistronic DNA vaccine construct pIR16.8/IFN was developed using eukaryotic vector pIRES 6.1. Two genes MPT (expressing 16.8 kDa protein) and murine IFNγ were cloned, expressed and immunoreactivity was studied in murine model. Immunoreactivity was also compared with monocistronic construct pIR16.8 expressing 16.8 kDa protein. Both pIR16.8 and pIR16.8/IFN showed eukaryotic expression of respective proteins in BHK21 cells. The expressed proteins also showed immunoreactivity when reacted with hyperimmune sera raised against recombinant 16.8 kDa protein in western blot assay and immunofluorence assay. Both constructs were used as DNA vaccine in murine model and immunogenecity was studied by DTH, lymphocyte proliferation assay and NO determination. DTH reaction was significantly high in pIR16.8/IFN than pIR16.8 group, similarly lymphocyte proliferation and NO release was higher in pIR16.8/IFN group than pIR16.8 group. This indicated T cell epitopic nature of 16.8 kDa protein. The study also showed that co-expression of IFNγ with mycobacterial gene can enhance immunogenecity of DNA vaccine and can be used as immunoadjuvant.  相似文献   
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